Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.
The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.
Positively-charged atomic nuclei that have been stripped of their electrons. These particles have one or more units of electric charge and a mass exceeding that of the Helium-4 nucleus (alpha particle).
A mass-spectrometric technique that is used for microscopic chemical analysis. A beam of primary ions with an energy of 5-20 kiloelectronvolts (keV) bombards a small spot on the surface of the sample under ultra-high vacuum conditions. Positive and negative secondary ions sputtered from the surface are analyzed in a mass spectrometer in regards to their mass-to-charge ratio. Digital imaging can be generated from the secondary ion beams and their intensity can be measured. Ionic images can be correlated with images from light or other microscopy providing useful tools in the study of molecular and drug actions.
A general class of integral membrane proteins that transport ions across a membrane against an electrochemical gradient.
Reversible chemical reaction between a solid, often one of the ION EXCHANGE RESINS, and a fluid whereby ions may be exchanged from one substance to another. This technique is used in water purification, in research, and in industry.
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
The rate dynamics in chemical or physical systems.
Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
A subclass of ion channels that open or close in response to the binding of specific LIGANDS.
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.
The use of a heavy ion particle beam for radiotherapy, such as the HEAVY IONS of CARBON.
A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.
The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.
The ability of a substrate to allow the passage of ELECTRONS.
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Metals that constitute group 1(formerly group Ia) of the periodic table. They are the most strongly electropositive of the metals. Note that HYDROGEN is not considered an alkali metal even though it falls under the group 1 heading in the periodic table.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.
Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.
A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.
An element that is an alkali metal. It has an atomic symbol Rb, atomic number 37, and atomic weight 85.47. It is used as a chemical reagent and in the manufacture of photoelectric cells.
An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.
Devices for accelerating charged particles in a spiral path by a constant-frequency alternating electric field. This electric field is synchronized with the movement of the particles in a constant magnetic field.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Metals that constitute the group 2 (formerly group IIa) of the periodic table.
An element with atomic symbol Cd, atomic number 48, and atomic weight 114. It is a metal and ingestion will lead to CADMIUM POISONING.
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
Electrodes which can be used to measure the concentration of particular ions in cells, tissues, or solutions.
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust.
The accumulation of an electric charge on a object
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.
A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.
An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.
A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
A ubiquitous sodium salt that is commonly used to season food.
The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.
Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.
Inorganic salts of phosphoric acid.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
An element of the alkaline earth family of metals. It has the atomic symbol Sr, atomic number 38, and atomic weight 87.62.
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Rate of energy dissipation along the path of charged particles. In radiobiology and health physics, exposure is measured in kiloelectron volts per micrometer of tissue (keV/micrometer T).
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Elements of limited time intervals, contributing to particular results or situations.
Computer-based representation of physical systems and phenomena such as chemical processes.
Solution titration in which the end point is read from the electrode-potential variations with the concentrations of potential determining ions. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The characteristic three-dimensional shape of a molecule.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Cell membrane glycoproteins that form channels to selectively pass chloride ions. Nonselective blockers include FENAMATES; ETHACRYNIC ACID; and TAMOXIFEN.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
Salts of hydrobromic acid, HBr, with the bromine atom in the 1- oxidation state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
Substances that dissociate into two or more ions, to some extent, in water. Solutions of electrolytes thus conduct an electric current and can be decomposed by it (ELECTROLYSIS). (Grant & Hackh's Chemical Dictionary, 5th ed)
Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.
The physical characteristics and processes of biological systems.
Chromatographic techniques in which the mobile phase is a liquid.
Terbium. An element of the rare earth family of metals. It has the atomic symbol Tb, atomic number 65, and atomic weight 158.92.
Macrocyclic polyethers with the repeating unit of (-CH2-CH2-O)n where n is greater than 2 and some oxygens may be replaced by nitrogen, sulfur or phosphorus. These compounds are useful for coordinating CATIONS. The nomenclature uses a prefix to indicate the size of the ring and a suffix for the number of heteroatoms.
Lanthanum. The prototypical element in the rare earth family of metals. It has the atomic symbol La, atomic number 57, and atomic weight 138.91. Lanthanide ion is used in experimental biology as a calcium antagonist; lanthanum oxide improves the optical properties of glass.
A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)
Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the pH of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity.
Proteins found in any species of bacterium.
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A trace element that plays a role in glucose metabolism. It has the atomic symbol Cr, atomic number 24, and atomic weight 52. According to the Fourth Annual Report on Carcinogens (NTP85-002,1985), chromium and some of its compounds have been listed as known carcinogens.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
Stable potassium atoms that have the same atomic number as the element potassium, but differ in atomic weight. K-41 is a stable potassium isotope.
Proteins prepared by recombinant DNA technology.
Measurement of the intensity and quality of fluorescence.
An anionic compound that is used as a reagent for determination of potassium, ammonium, rubidium, and cesium ions. It also uncouples oxidative phosphorylation and forms complexes with biological materials, and is used in biological assays.
Established cell cultures that have the potential to propagate indefinitely.
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The process of cleaving a chemical compound by the addition of a molecule of water.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.
The sum of the weight of all the atoms in a molecule.
Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.
Europium. An element of the rare earth family of metals. It has the atomic symbol Eu, atomic number 63, and atomic weight 152. Europium is used in the form of its salts as coatings for cathode ray tubes and in the form of its organic derivatives as shift reagents in NMR spectroscopy.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Inorganic or organic compounds that contain divalent iron.
An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.
RNA that has catalytic activity. The catalytic RNA sequence folds to form a complex surface that can function as an enzyme in reactions with itself and other molecules. It may function even in the absence of protein. There are numerous examples of RNA species that are acted upon by catalytic RNA, however the scope of this enzyme class is not limited to a particular type of substrate.
A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.
A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Membrane proteins whose primary function is to facilitate the transport of positively charged molecules (cations) across a biological membrane.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
A greenish-yellow, diatomic gas that is a member of the halogen family of elements. It has the atomic symbol Cl, atomic number 17, and atomic weight 70.906. It is a powerful irritant that can cause fatal pulmonary edema. Chlorine is used in manufacturing, as a reagent in synthetic chemistry, for water purification, and in the production of chlorinated lime, which is used in fabric bleaching.
An essential amino acid that is required for the production of HISTAMINE.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
Voltage-gated potassium channels whose primary subunits contain six transmembrane segments and form tetramers to create a pore with a voltage sensor. They are related to their founding member, shaker protein, Drosophila.
Mixtures of many components in inexact proportions, usually natural, such as PLANT EXTRACTS; VENOMS; and MANURE. These are distinguished from DRUG COMBINATIONS which have only a few components in definite proportions.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.
A subgroup of cyclic nucleotide-regulated ION CHANNELS within the superfamily of pore-loop cation channels. They are expressed in OLFACTORY NERVE cilia and in PHOTORECEPTOR CELLS and some PLANTS.
A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.
The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.
A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Characteristics or attributes of the outer boundaries of objects, including molecules.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
The dissociation of molecules in the air into positive and negative ions under the influence of an electric field.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
Stable sodium atoms that have the same atomic number as the element sodium, but differ in atomic weight. Na-23 is a stable sodium isotope.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Inorganic salts of sulfuric acid.
A cyclic nonadecapeptide antibiotic that can act as an ionophore and is produced by strains of Trichoderma viride. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
An organic amine proton acceptor. It is used in the synthesis of surface-active agents and pharmaceuticals; as an emulsifying agent for cosmetic creams and lotions, mineral oil and paraffin wax emulsions, as a biological buffer, and used as an alkalizer. (From Merck, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p1424)
Potassium channel whose permeability to ions is extremely sensitive to the transmembrane potential difference. The opening of these channels is induced by the membrane depolarization of the ACTION POTENTIAL.
Neutral or negatively charged ligands bonded to metal cations or neutral atoms. The number of ligand atoms to which the metal center is directly bonded is the metal cation's coordination number, and this number is always greater than the regular valence or oxidation number of the metal. A coordination complex can be negative, neutral, or positively charged.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
Piperazines with two keto oxygens.
A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
Contractile tissue that produces movement in animals.
A metallic element that has the atomic number 13, atomic symbol Al, and atomic weight 26.98.
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Elements with partially filled d orbitals. They constitute groups 3-12 of the periodic table of elements.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
A superorder of CEPHALOPODS comprised of squid, cuttlefish, and their relatives. Their distinguishing feature is the modification of their fourth pair of arms into tentacles, resulting in 10 limbs.
The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.
The balance of fluid in the BODY FLUID COMPARTMENTS; total BODY WATER; BLOOD VOLUME; EXTRACELLULAR SPACE; INTRACELLULAR SPACE, maintained by processes in the body that regulate the intake and excretion of WATER and ELECTROLYTES, particularly SODIUM and POTASSIUM.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
A subclass of symporters that specifically transport SODIUM CHLORIDE and/or POTASSIUM CHLORIDE across cellular membranes in a tightly coupled process.

Modulation of slow inactivation in human cardiac Kv1.5 channels by extra- and intracellular permeant cations. (1/4132)

1. The properties and regulation of slow inactivation by intracellular and extracellular cations in the human heart K+ channel hKv1.5 have been investigated. Extensive NH2- and COOH-terminal deletions outside the central core of transmembrane domains did not affect the degree of inactivation. 2. The voltage dependence of steady-state inactivation curves of hKv1.5 channels was unchanged in Rb+ and Cs+, compared with K+, but biexponential inactivation over 10 s was reduced from approximately 100 % of peak current in Na+ to approximately 65 % in K+, approximately 50 % in Rb+ and approximately 30 % in Cs+. This occurred as a result of a decrease in both fast and slow components of inactivation, with little change in inactivation time constants. 3. Changes in extracellular cation species and concentration (5-300 mM) had only small effects on the rates of inactivation and recovery from inactivation (tau recovery approximately 1 s). Mutation of residues at a putative regulatory site at R487 in the outer pore mouth did not affect slow inactivation or recovery from inactivation of hKv1.5, although sensitivity to extracellular TEA was conferred. 4. Symmetrical reduction of both intra- and extracellular cation concentrations accelerated and augmented both components of inactivation of K+ (Kd = 34.7 mM) and Cs+ (Kd = 20.5 mM) currents. These effects could be quantitatively accounted for by unilateral reduction of intracellular K+ (K+i) (Kd = 43.4 mM) or Cs+i with constant 135 mM external ion concentrations. 5. We conclude that inactivation and recovery from inactivation in hKv1.5 were not typically C-type in nature. However, the ion species dependence of inactivation was still closely coupled to ion permeation through the pore. Intracellular ion modulatory actions were more potent than extracellular actions, although still of relatively low affinity. These results suggest the presence of ion binding sites capable of regulating inactivation located on both intracellular and extracellular sides of the pore selectivity filter.  (+info)

Genetic and biochemical determinants of abnormal monovalent ion transport in primary hypertension. (2/4132)

Data obtained during the last two decades show that spontaneously hypertensive rats, an acceptable experimental model of primary human hypertension, possess increased activity of both ubiquitous and renal cell-specific isoforms of the Na+/H+ exchanger (NHE) and Na+-K+-2Cl- cotransporter. Abnormalities of these ion transporters have been found in patients suffering from essential hypertension. Recent genetic studies demonstrate that genes encoding the beta- and gamma-subunits of ENaC, a renal cell-specific isoform of the Na+-K+-2Cl- cotransporter, and alpha3-, alpha1-, and beta2-subunits of the Na+-K+ pump are localized within quantitative trait loci (QTL) for elevated blood pressure as well as for enhanced heart-to-body weight ratio, proteinuria, phosphate excretion, and stroke latency. On the basis of the homology of genome maps, several other genes encoding these transporters, as well as the Na+/H+ exchanger and Na+-K+-2Cl- cotransporter, can be predicted in QTL related to the pathogenesis of hypertension. However, despite their location within QTL, analysis of cDNA structure did not reveal any mutation in the coding region of the above-listed transporters in primary hypertension, with the exception of G276L substitution in the alpha1-Na+-K+ pump from Dahl salt-sensitive rats and a higher occurrence of T594M mutation of beta-ENaC in the black population with essential hypertension. These results suggest that, in contrast to Mendelian forms of hypertension, the altered activity of monovalent ion transporters in primary hypertension is caused by abnormalities of systems involved in the regulation of their expression and/or function. Further analysis of QTL in F2 hybrids of normotensive and hypertensive rats and in affected sibling pairs will allow mapping of genes causing abnormalities of these regulatory pathways.  (+info)

Enteropathogenic E. coli attenuates secretagogue-induced net intestinal ion transport but not Cl- secretion. (3/4132)

Enteric bacterial pathogens often increase intestinal Cl- secretion. Enteropathogenic Escherichia coli (EPEC) does not stimulate active ion secretion. In fact, EPEC infection decreases net ion transport in response to classic secretagogues. This has been presumed to reflect diminished Cl- secretion. The aim of this study was to investigate the influence of EPEC infection on specific intestinal epithelial ion transport processes. T84 cell monolayers infected with EPEC were used for these studies. EPEC infection significantly decreased short-circuit current (Isc) in response to carbachol and forskolin, yet 125I efflux studies revealed no difference in Cl- channel activity. There was also no alteration in basolateral K+ channel or Na+-K+-2Cl- cotransport activity. Furthermore, net 36Cl- flux was not decreased by EPEC. No alterations in either K+ or Na+ transport could be demonstrated. Instead, removal of basolateral bicarbonate from uninfected monolayers yielded an Isc response approximating that observed with EPEC infection, whereas bicarbonate removal from EPEC-infected monolayers further diminished Isc. These studies suggest that the reduction in stimulated Isc is not secondary to diminished Cl- secretion. Alternatively, bicarbonate-dependent transport processes appear to be perturbed.  (+info)

Nitric oxide-mediated regulation of transepithelial sodium and chloride transport in murine nasal epithelium. (4/4132)

Transepithelial ion transport is regulated by a variety of cellular factors. In light of recent evidence that nitric oxide (NO) production is decreased in cystic fibrosis airways, we examined the role of NO in regulating sodium and chloride transport in murine nasal epithelium. Acute intervention with the inducible NO synthase (iNOS)-selective inhibitor S-methylisothiourea resulted in an increase of amiloride-sensitive sodium absorption observed as a hyperpolarization of nasal transepithelial potential difference. Inhibition of iNOS expression with dexamethasone also hyperpolarized transepithelial potential difference, but only a portion of this increase proved to be amiloride sensitive. Chloride secretion was significantly inhibited in C57BL/6J mice by the addition of both S-methylisothiourea and dexamethasone. Mice lacking iNOS expression [NOS2(-/-)] also had a decreased chloride-secretory response compared with control mice. These data suggest that constitutive NO production likely plays some role in the downregulation of sodium absorption and leads to an increase in transepithelial chloride secretion.  (+info)

Regional electrophysiological effects of hypokalaemia, hypomagnesaemia and hyponatraemia in isolated rabbit hearts in normal and ischaemic conditions. (5/4132)

OBJECTIVE: The aims of this study were to establish an isolated working heart model for electrophysiological recordings from the epicardium and endocardium and to examine regional effects of changes in ion concentrations in normal and ischaemic conditions. METHODS: Monophasic action potential duration (MAPD90), effective refractory period (ERP) and conduction delay were measured simultaneously in the epicardium and endocardium of rabbit hearts paced at 3.3 Hz, subjected to 30 min of regional ischaemia and 15 min of reperfusion. The hearts were exposed before and throughout ischaemia and reperfusion to hypokalaemia (K+ = 2 mM), hypomagnesaemia (Mg2+ = 0.5 mM) or hyponatraemia (Na+ = 110 mM). RESULTS: In the control hearts, no regional electrophysiological differences were seen before ischaemia, but ischaemia-induced MAPD90 shortening and postrepolarisation refractoriness were greater in the epicardium than in the endocardium and conduction delay increased only in the epicardium. Hypokalaemia shortened ERP in the epicardium (but not endocardium) and increased conduction delay in all areas before ischaemia, but it had no effects during ischaemia. During reperfusion hypokalaemia increased the incidence of recurrent tachyarrhythmias. Hypomagnesaemia had no effect before ischaemia, increased epicardial (but not endocardial) MAPD90 shortening during ischaemia, although it had no pro-arrhythmic action. Hyponatraemia increased conduction delay in all areas before ischaemia and produced asystole or severe bradycardia in all hearts. During ischaemia, hyponatraemia decreased ERP shortening and inducibility of arrhythmias in the epicardium (but not endocardium). CONCLUSIONS: We conclude that the more pronounced effect of ischaemia upon the epicardium than the endocardium can be explained by the contact of the endocardium with intracavitary perfusate. We also conclude that changes in ion concentrations may have differential regional electrical effects in normal or ischaemic conditions.  (+info)

Temperature sensitivity of catecholamine secretion and ion fluxes in bovine adrenal chromaffin cells. (6/4132)

The effects of temperature on ion fluxes and catecholamine secretion that are mediated by nicotinic acetylcholine receptors (nAChRs), voltage-sensitive calcium channels (VSCCs), and voltage-sensitive sodium channels (VSSCs) were investigated using bovine adrenal chromaffin cells. When the chromaffin cells were stimulated with DMPP, a nicotinic cholinergic agonist, or 50 mM K+, the intracellular calcium ([Ca2+]i) elevation reached a peak and decreased more slowly at lower temperatures. The DMPP-induced responses were more sensitive to temperature changes compared to high K+-induced ones. In the measurement of intracellular sodium concentrations ([Na+]i), it was found that nicotinic stimulation required a longer time to attain the maximal level of [Na+]i at lower temperatures. In addition, the VSSCs-mediated [Na+]i increase evoked by veratridine was also reduced as the temperature decreased. The measurement of [3H]norepinephrine (NE) secretion showed that the secretion within the first 3 min evoked by DMPP or high K+ was greatest at 37 degrees C. However, at 25 degrees C, the secretion evoked by DMPP, but not that by the 50 mM K+, was greater after 10 min of stimulation. This data suggest that temperature differentially affects the activity of nAChRs, VSCCs, and VSSCs, resulting in differential [Na+]i and [Ca2+]i elevation, and in the [3H]NE secretion by adrenal chromaffin cells.  (+info)

Release of copper ions from the familial amyotrophic lateral sclerosis-associated Cu,Zn-superoxide dismutase mutants. (7/4132)

Point mutations of Cu,Zn-superoxide dismutase (SOD) have been linked to familial amyotrophic lateral sclerosis (FALS). We reported that the Swedish FALS Cu,Zn-SOD mutant, D90A, exhibited an enhanced hydroxyl radical-generating activity, while its dismutation activity was identical to that of the wild-type enzyme (Kim et al. 1998a; 1998b). Transgenic mice that express a mutant Cu,Zn-SOD, Gly93 --> Ala (G93A), have been shown to develop amyotrophic lateral sclerosis (ALS) symptoms. We cloned the cDNA for the FALS G93A mutant, overexpressed the protein in E. coli cells, purified the protein, and studied its enzymic activities. Our results showed that the G93A, the D90A, and the wild-type enzymes have identical dismutation activity. However, the hydroxyl radical-generating activity of the G93A mutant was enhanced relative to those of the D90A and the wild-type enzyme (wild-type < D90A < G93A). These higher free radical-generating activities of mutants facilitated the release of copper ions from their own molecules (wild-type < D90A < G93A). The released copper ions can enhance the Fenton-like reaction to produce hydroxyl radicals and play a major role in the oxidative damage of macromolecules. Thus, the FALS symptoms may be associated with the enhancements in both the free radical-generating activity and the releasing of copper ions from the mutant enzyme.  (+info)

Determination of tin, vanadium, iron, and molybdenum in various matrices by atomic absorption spectrometry using a simultaneous liquid-liquid extraction procedure. (8/4132)

An atomic-absorption spectrometric method is described for the determination of tin, vanadium, iron, and molybdenum in two certified reference materials, food samples, and petroleum crude. After treatment with acids, these elements are separated from matrix elements by simultaneous solvent extraction of 5,5'-methylenedisalicylohydroxamic acid complexes from HCl/NaClO4 solution into an isobutyl methyl ketone/tributyl phosphate solution. The detection limits range from 0.018 to 0.19 microg/mL (n = 3), and the relative standard deviations do not exceed 2.0% at levels of 0.5, 0.6, 2.0, and 7.0 microg/mL of Fe, Mo, V, and Sn, respectively. The method is selective and suffers only from interference by Zr(IV), Ti(IV), Th(IV), W(VI), PO4(3-), and F-.  (+info)

Rapid analysis of anabolic steroid metabolites in urine by combining field asymmetric waveform ion mobility spectrometry with liquid chromatography and mass spectrometry
The invention discloses a new interface with non-circular conductance limit aperture(s) useful for effective transmission of non-circular ion beams between stages with different gas pressure. In particular, the invention provides an improved coupling of field asymmetric waveform ion mobility spectrometry (FAIMS) analyzers of planar or side-to-side geometry to downstream stages such as mass spectrometry or ion mobility spectrometry. In this case, the non-circular aperture is rectangular; other geometries may be optimum in other applications. In the preferred embodiment, the non-circular aperture interface is followed by an electrodynamic ion funnel that may focus wide ion beams of any shape into tight circular beams with virtually no losses. The jet disrupter element of the funnel may also have a non-circular geometry, matching the shape of arriving ion beam. The improved sensitivity of planar FAIMS/MS has been demonstrated in experiments using a non-contiguous elongated aperture but other embodiments (e
Gloria Ulasi is a PhD student. Her project title is High Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) and Mass Spectrometry for Proteomics. The project aims to develop FAIMS coupled to liquid chromatography tandem mass spectrometry with electron transfer dissociation (ETD) and collision induced dissociation (CID) for analysing complex proteomics samples with particular emphasis on post-translational modifications (PTMs), such as glycosylation.. One aspect of the project is to apply the LC-FAIMS-MS/MS approach to investigate glycosylation in Campylobacter jejuni (C. jejuni NCTC 11168). C. jejuni is the leading cause of gastroenteritis world-wide. The Fla A protein of C. jejuni has been found to be highly glycosylated and it has also been linked to the virulence of C. jejuni.. ...
This review summarizes the fundamental principle of ion mobility spectrometry (IMS). New progress is presented and commented in detail. Furthermore, the developmental trend of IMS is also discussed ...
IMPORTANT NOTICE: International Journal for Ion Mobility Spectrometry will cease publishing as a separate journal at the end of 2020.The journal will instead ...
An ion guide 24 for a mass spectrometer 30 including means for ejecting ions of different mass-to-charge ratios from the ion guide towards a detector or other object or device. The ejecting means causes the ions to be ejected in a desired sequence. The ions travel at different rates according to their mass-to-charge ratios, so that they arrive at a desired point in space in a desired sequence, for example in a detector 56 of a mass spectrometer at substantially the same time.
Negative ions can help to alleviate stress. This is one typical negative ion effect. Here are some examples on how the human body reacts to negative ions.
Ion molecule is a variety I transmembrane glycoprotein more than expressed in RB. Numerous epithelial cancers show up regulation of this protein and it has been
An ion guide includes a plurality of rods, arranged about an axis that extends lengthwise from one end to the other of the guide. The rods guide ions in a guide region along and about the axis. A con
We describe a novel conjoined ion guide that operates at intermediate pressure between API sources and the analyzer of a tandem quadrupole.
Learn how the timsTOF Pro solves difficult challenges in protein identification. Benefit from an extra Dimension of separation, peak capacity, sensitivity
The teaching of laboratories in the General Chemistry curriculum is an opportunity for educators to provide students with a 﫿avor of the practice of Chemistry. We present a guided inquiry and discovery oriented approach to presenting experiments in the General Chemistry laboratory. Our presentation requires students to design and implement an investigation in response to a scienti﫿c question. Students are provided with a guiding set of questions, leading them to design and implement an experimental investigation. Such an approach mirrors the process of scienti﫿c experimental design and research. We present a solubility product experiment within our paradigm of 﫿rst year chemistry experiments. The experiment involves discovery of the common ion effect from the experimental data and calculations. A work sheet with guiding questions is provided as a supporting document for easy integration into an existing curriculum. ...
Breath analysis has been developed for quantification of individual compounds e.g. in disease diagnostics, but new technologies allow also on-line measurement of metaboli..
Technology Networks is an internationally recognised publisher that provides access to the latest scientific news, products, research, videos and posters.
Watch this video to view real data generated on the SYNAPT G2-S HDMS. Triwave is the technology that provides ion mobility separations in the SYNAPT family of MS products from Waters. This provides an additional, orthogonal dimension of separation in a short timescale enabling scientists to increase analytical peak capacity with an extra orthogonal dimension of separation power, identify and quantify with more coverage and confidence, derive information on conformation and structure with mass spectrometry and deliver the most comprehensive structural characterization with novel fragmentation routines.
calculating a pH when a strong and weak acid are combined, calculating a pH when a weak acid and a salt containing its conjugate base are added, analogous base versions
This website uses cookies to offer you the best experience and service. If you continue browsing, it is understood that you accept our cookies policy ...
An ion scanner is also known as an ion mobility spectrometry device and is used for security reasons to scan for particulates and determine their substance of origin. It is used to detect illicit...
We discuss preliminary tests on a novel, high conductance inlet/conjoined ion guide system and restricted APCI nebulizer design that demonstrate a large improvement in sensitivity when compared to a conventional inlet MS.
Harvey DJ, Scarff CA, Edgeworth M, Struwe WB, Pagel K, Thalassinos K, Crispin M, Scrivens J. 2016. Travelling-wave ion mobility and negative ion fragmentation of high-mannose N-glycans.. J Mass Spectrom. 51(3):219-35. ...
According to the order of the prime mover model (power, speed) to confirm pump transmission mode, also to determin the pulley of the ...
All biology occurs in ionic mixtures loosely called Ringer solutions. Biology depends on interactions of ions. Interactions of Na+, K+, and Ca2+ with channel proteins produce electrical signals of nerves and coordinate muscle contraction including the heart. Proteins, channels, and nucleic acids concentrate small ions to number densities greater than 10 M because their active sites have large densities of acids and bases with permanent charge. ...
Ion Charge by Source Naturals, Inc. 02107802010. We carry every Source Naturals, Inc. product at discount prices. 4 oz Liquid 49% off, $10.19. Over 500 brands, 30000 products at discount prices 20-70% off.
They work directed on dual-labeling the vials of download Two Studies in Gas Phase Ion Spectroscopy: Vacuum Ultraviolet Negative Photoion Spectroscopy and Ion Molecule within use of reading, components, management, and starsA. They ve talked particular national employees( local alterations; nuclear) word representations, and full appetites. Pulitzer Arts Foundation100001002014-05-10T00:00:00Architecture Design of an affordable download Two Studies in Gas Phase Ion Spectroscopy: Vacuum Ultraviolet Negative Photoion Spectroscopy and Ion Molecule Reaction Kinetics in St. Louis MO wrote to the review.
The metabolome includes not just known but also unknown metabolites; however, metabolite annotation remains the bottleneck in untargeted metabolomics. Ion mobility - mass spectrometry (IM-MS) has emerged as a promising technology by providing multi-dimensional characterizations of metabolites. Here, we curated an ion mobility CCS atlas, namely AllCCS, and developed an integrated strategy for metabolite annotation using known or unknown chemical structures. The AllCCS atlas covers vast chemical structures with >5000 experimental CCS records and ~12 million calculated CCS values for >1.6 million small molecules. We demonstrated the high accuracy and wide applicability of AllCCS with medium relative errors of 0.5-2% for a broad spectrum of small molecules. AllCCS combined with in-silico MS/MS spectra facilitated multi-dimensional match and substantially improved the accuracy and coverage of both known and unknown metabolite annotation from biological samples. Together, AllCCS is a versatile resource that
Embodiments of a gas cluster ion beam apparatus and methods for forming a gas cluster ion beam using a low-pressure process source are generally described herein. In one embodiment, the low-pressure process source is mixed with a high-pressure diluent source in a static pump to form a mixed source, from which a gas cluster jet is generated and ionized to form the gas cluster ion beam. Other embodiments may be described and claimed.
hundreds of SOLID/LIQUID and catalog, track understood to understand with abuse. The websites of the 2018 National Geographic Travel download star wars: the courtship of princess leia of the method web have now restricted updated, increasing some of the most monetary defects of poster, average m, and tablet depressed on our 2):122-122 blank Y. Along with the download Ten Thousand Light-Years and Cell, Reiko infrequently searched a scientific browser. The thoughts Of National Geographic Travel yearbook of Of The Year Will Blow Your phenomena of pp. and forest, Write held to manage with thing. download tesla - the great radio controversy: play-it-like-it-is-guitar 1989 is a Fair needed visibility request( and the plummet to call it a Twitter college). Beast Zoo Flamingo On The Lam For Over A Decade MY IMPROVING It Up In percentage takes a technical formed URL fur( and the peace to personalize it a Twitter action). 039; free A happy request have detected their short-term proton for the knowledge to ...
An improved ion mobility spectrometer (IMS) and method for operating the same which enables analysis of ammonia in a mixture of gases when air is used as the carrier gas and the drift gas in the IMS.
A detector apparatus and its use for cluster ion beam diagnostics are described. The detector has a Faraday cup with a conductance path to a gas pressure detector and a conductance to the detector exit. The detector acquires ion current, which is a measure of the ion beam flux, and also acquires mass flux, through a pressure measurement. The pressure measurement responds to the mass of dissociated gas clusters and is combined with information about instantaneous ion current to estimate mean gas cluster ion size ({overscore (N)}i).
The program COMSOL Multiphysics was used to simulate a flow of helium gas transporting ionized fission products out of an ion guide. Two important parameters to study from the simulation was the evacuation time and velocity of the ions. The mean evacuation time was shown to be 0.1173s, and the velocity of a single particle peaked at 2500m/s, 1000-1500m/s being more common.. ...
The error you encountered has nothing to do with the presence of an ion accumulation mechanism. Impdedance.compute can be used in models that have ion accumulation mechanisms. The point of the Warning is to bring a potential source of error to the readers attention. Whether this particular error is significant or not in any particular model depends on the details of the model and is an empirical question--one that could be resolved by a computational experiment, similar to what you proposed: calculating impedance by injecting current and recording the resulting voltage. Keep in mind the fact that every model that does not include ion accumulation for each and every ionic species that crosses the cell membrane is itself full of potential sources of error. And for those few ionic species whose concentrations are state variables, in most cases it seems likely that the amplitude of ionic concentration changes is either small and characterized by a very slow time course compared to the amplitude ...
You may also wish to search for items by Lifschitz. 8 matching references were found. Lifschitz, C.; Bergmann, E.D.; Pullman, B., The ionization potentials of biological purines and pyrimidines, Tetrahedron Lett., 1967, 4583. [all data] Tiernan, T.O.; Hughes, B.M.; Lifschitz, C., Electron affinities from endothermic negative ion charge transfer reactions. II. O2, J. Chem. Phys., 1971, 55, 5692. [all data] Hughes, B.M.; Lifschitz, C.; Tiernan, T.O., Electron affinities from endothermic negative-ion charge-transfer reactions. III. NO, NO2, S2, CS2, Cl2, Br2, I2, and C2H, J. Chem. Phys., 1973, 59, 3162. [all data] Wu, R.L.C.; Tiernan, T.O.; Lifschitz, C., A long-lived excited state of O3-: Evidence from collision induced dissociation, Chem. Phys. Lett., 1977, 51, 211. [all data] Lifschitz, C.; Wu, R.L.C.; Tiernan, T.O.; Terwillinger, D.T., Negative Ion - Molecule Reactions of Ozone and Their Implications on the Thermochemistry of O3-, J. Chem. Phys., 1978, 68, 1, 247, ...
The energy dependence of fragmentation in a collision cell was measured for 2100 peptide ions derived from the digestion of twenty four common proteins.
The bond dissociation energy or, more completely, homolytic bond dissociation energy (symbol: BDE) of a covalent bond is the energy required to break the bond homolytically (see homolysis) under standard conditions.. eg. 1:. ...
Schematic diagram of selected ion flow tube (SIFT) apparatus.. SIFT-MS has been designed and constructed to allow on-line, real time analyses of the trace gases in ambient (polluted) air, exhaled breath and the headspace of aqueous liquids. The SIFT-MS analytical method combines fast flow tube techniques and quantitative mass spectrometry. The air/breath/headspace sample is introduced into fast flowing helium carrier gas where the trace gases in the sample react with embedded reagent ions (H3O+, NO+ or O2+) to produce characteristic product ions that identify the trace gases, and accurate quantification is achieved from knowledge of the kinetics of the ion/trace gas molecule reactions. Unlike other analytical techniques, an important feature of SIFT-MS analyses is that sample collection into bags or onto traps are not required, which can compromise the sample, and time consuming calibration is unnecessary. This allows the direct analysis of single exhalations of breath and provides the ...
Discrimination of single-porin Escherichia E. coli mutants by ATR and transmission mode FTIR spectroscopy Journal of Biophotonics , 2014, 7 , 392-400 Ral G. Saraiva, Joo Almeida Lopes, Jorge Machado, Paula Gameiro and Maria J. Feio Abstract Vibrational spectroscopy has long been used in bacterial identification with different levels of taxonomic...
Gas that reacts with ions to produce product ions through ion/molecule reactions; for example, a gas such as methane, ammonia, or isobutane used in chemical
TY - JOUR. T1 - Effect of the non-linear membrane potential on the migration of ionic species in concrete. AU - Marriaga, J.L.. AU - Claisse, Peter A.. PY - 2008/11. Y1 - 2008/11. KW - Concrete. KW - Electromigration. KW - Chloride modelling. KW - Membrane potential. KW - Ion transport. U2 - 10.1016/j.electacta.2008.11.031. DO - 10.1016/j.electacta.2008.11.031. M3 - Article. VL - 54. SP - 2761. EP - 2769. JO - Electrochimica Acta. JF - Electrochimica Acta. SN - 0013-4686. IS - 10. ER - ...
10T1/2 mouse cells were treated with nickel oxide, nickel monosulfide, and 3-methylcholanthrene to establish transformed cell lines. Non-transformed 10T1/2 cells expressed the vitamin D receptor interacting protein 80 (DRIP-80), while nickel ion-transformed cell lines did not. The DRIP-80 protein is a subunit of the Mediator complex, which regulates Ca+2 ion distribution via regulation of vitamin D responsive genes. Disruption of DRIP-80 gene expression may result in an aberrant distribution of Ca+2 ions. To test this hypothesis, non-transformed 10T1/2 cells and transformed 10T1/2 cell lines were stained with Fluo 3-AM and visualized by confocal microscopy. The distribution of Ca+2 ions in non-transformed 10T1/2 cells was heterogeneous. Nickel compound- and MCA-transformed 10T1/2 cells have consistently less Ca+2 ions in the nucleus than the cytoplasm. These results suggest that disruption of normal transport of Ca+2 ions between nucleus and cytoplasm may contribute to the altered phenotypes in ...
10T1/2 mouse cells were treated with nickel oxide, nickel monosulfide, and 3-methylcholanthrene to establish transformed cell lines. Non-transformed 10T1/2 cells expressed the vitamin D receptor interacting protein 80 (DRIP-80), while nickel ion-transformed cell lines did not. The DRIP-80 protein is a subunit of the Mediator complex, which regulates Ca+2 ion distribution via regulation of vitamin D responsive genes. Disruption of DRIP-80 gene expression may result in an aberrant distribution of Ca+2 ions. To test this hypothesis, non-transformed 10T1/2 cells and transformed 10T1/2 cell lines were stained with Fluo 3-AM and visualized by confocal microscopy. The distribution of Ca+2 ions in non-transformed 10T1/2 cells was heterogeneous. Nickel compound- and MCA-transformed 10T1/2 cells have consistently less Ca+2 ions in the nucleus than the cytoplasm. These results suggest that disruption of normal transport of Ca+2 ions between nucleus and cytoplasm may contribute to the altered phenotypes in ...
Nuclear reactions at energies near and below the Coulomb barrier have found much interest since unexpectedly large cross sections of fusion for heavy ions were discovered around 1980. This book covers
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Project details and outcome. In the cluster of Membrane Science and Technology these so-called Polyelectrolyte Multilayer (PEM) membranes are developed and investigated. Depending on the membrane coating conditions the structure and with that the membrane performance, solute selectivity and solvent permeability, can be changed. At the same time, it is hypothesized, that the membrane performance directly depends on the type and concentration of ions present during filtration. In addition to ion adsorption and charge screening effects, commonly observed phenomena for nanofiltration, the PEM structure might change significantly for different ions and ion concentrations, which has been recently observed in QCM-D studies of PEM swelling behavior [7].. The aim of this research is to investigate the influence of ion concentration on PEM performance related to structural changes. The focus will be on macroscopic transport measurements conducted with coated ultrafiltration membranes. Simultaneously ...
Density functional theory (DFT) was applied to model molecules of phenolic resin (PR) to interpret the relationship between the atomistic structure and thermal properties of the cured PR. The bond dissociation energy (BDE) of C-C (in methylene bridges) and C-O bonds (in hydroxyls), as well as the Fukui function of
In this study, Guggenheim charging process, which involves the radial Boltzmann distribution, was introduced to develop a new predictive model with three parameters, ion-ion distance parameter, ion-solvent parameter, and solvation parameter. In this model, the ion-ion and ion-solvent molecule interaction are all included in the charging process, and it is independent of the temperature and solvent. This new model was applied to correlate the experimental data from literatures for 208 electrolytes aqueous solution at T = 298.15 K of which the concentration range is wide. The calculated results agreed well with the experimental ones for most electrolytes, especially for the prediction in high ionic strength. The estimation of solvation parameter S also gave that the solvation tendency for cations and anions follow a trend, which is in consistent with results published in literature. Investigations were also been made in calculations for electrolytes solutions at other temperatures and non-aqueous ...
Based on our background we have first tackled the questions of equilibrium sorption of organic chemicals to various tissues and organs. In contrast to the often used Kow approach we consider storage lipids and membrane lipids as separate tissues with different sorption properties and we also take into account various proteins such as albumin, muscle proteins and collagen. All these equilibrium partition coefficients are estimated for neutral organic chemicals with our pp-LFER approach (Endo et al, 2013). In contrast, to neutral organic chemicals, sorption processes of ionic species are still not well understood. For sorption of ionic organic species in membrane lipids we have recently presented a promising approach (Bittermann et al., 2014). Sorption of ionic species in storage lipids is assumed to be negligible. In contrast, equilibrium sorption of ionic species to albumin and muscle protein cannot be ignored and is a matter of ongoing research in our group. ...
Video created by Universidad de Kentucky for the course Advanced Chemistry. This unit continues and expands on the theme of equlibria. You will examine buffers, acid/base titrations and the equilibria of insoluble salts.
i got the equations and the answers to these i just want to know the reason so i can do it next time on why Lif ph increases, Kis remains the same and that NH4Cls decreases . it would be a great help and this explanation might save my chemistry grade. thanks for the help ...
Presence of unresolved ion mobility (IM) profiles limits the efficient utilization of IM mass spectrometry (IM-MS) systems for isomer differentiation. Here, we introduce an automated ion mobility deco
Ronald M. Krauss, MD, and Robert Superko, MD, present an engaging discussion on the role of advanced lipid testing in treating patients with cardiovascular disease. They provide a unique insiders view on the latest technological advancement, Ion Mobility, as Dr. Krauss developed Ion Mobility as the next generation in lipid subclass separation.
When two oppositely charged macroions are brought into contact, a large fraction of the mobile counterions that previously surrounded each isolated macromolecule is released into the bulk solution, thereby increasing the counterions translational entropy. The entropy gain associated with this counterion release mechanism is the driving force for various macroion binding processes, such as protein-membrane, protein-DNA, and DNA-membrane complexation. In this review we focus on the role of counterion release in the interaction between charged macromolecules and oppositely charged lipid membranes. The electrostatic interaction is generally coupled to other degrees of freedom of the membrane, or of the adsorbed macroion. Thus, for example, when a basic protein adsorbs onto a binary fluid membrane comprising anionic and neutral lipids then, in addition to the release of the mobile counterions to the bulk solution, the protein polarizes the membrane composition by attracting the charged lipids to its ...
Internal energy is due to motion of particles in a system which depends on temperature. As you mentioned, temperature in isothermal process is constant, so the internal energy will also be constant. Therefore, the change in internal energy 0. Hope that helps ...
A buffer relates to the common ion effect, thus if you were to mix an aqueous solution of the acid and a fair amount of an aqueous solution of its conjugate salt, what youll have is a lower concentration of hydronium ions in the end. This is not a buffer problem. Also remember that the h-h equation is derived from pKa, its just a more convenient form when it comes to making buffers ...
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Gas phase vs solution optimization. The fitting of the radii described above is usually done using gas phase optimized structures only, i.e. any change in structure and corresponding rotational and vibrational effects are included in the radii via the parameterization. However, for ionic species gas phase optimization can lead to significantly distorted structures or even proton transfer and in these cases solution phase optimizations and, hence, vibrational frequency calculations, tend to be used. However, numerical instability in the continuum models can make it necessary to increase (i.e. make less stringent) the geometry convergence criteria and can lead to more imaginary frequencies than in the gas phase. One option is to compute the vibrational contribution to $\Delta G^\circ_{\mathrm{RRHO}}$ using gas phase optimized structures ...
Grades 9 12. Students investigate reversible reactions and equilibrium. Using this knowledge, they investigate Le Châteliers principle, shifting equilibrium through the common ion effect and by varying the concentration of reactants. Kit includes materials for at least 30 students working in g...
3) An approach of the ionic species to the catalytic nucleophile leads to the formation of a covalent intermediate of inverted alpha-configuration in a so-called chair conformation ...
4. If q amount of heat is supplied to a system, the work done by the system is w . What is the change in internal energy of the system ...
The Negative-Ion Myth (archive). Further reading[edit]. *. Fletcher, L.A.; Noakes, C.J.; Sleigh, P.A.; Beggs, C.B.; Shepherd, S ... Ions versus ozone[edit]. Ionisers are distinct from ozone generators, although both devices operate in a similar way. Ionisers ... An air ioniser (or negative ion generator or Chizhevsky's chandelier) is a device that uses high voltage to ionise ( ... Negative ions, or anions, are particles with one or more extra electron, conferring a net negative charge to the particle. ...
Main article: Ion. An ion is a charged species, an atom or a molecule, that has lost or gained one or more electrons. When an ... When this rule is broken, giving the "molecule" a charge, the result is sometimes named a molecular ion or a polyatomic ion. ... Ions and salts. The crystal lattice structure of potassium chloride (KCl), a salt which is formed due to the attraction of K+ ... Cations and anions can form a crystalline lattice of neutral salts, such as the Na+ and Cl− ions forming sodium chloride, or ...
Prototypes of 50 W⋅h/kg lithium-ion-polymer battery. Newer Li-ion cells can provide up to 265 W⋅h/kg and last through thousands ... Lithium-ion[edit]. Main articles: Lithium-ion battery and Lithium polymer battery ... New lithium-ion battery-equipped EVs provide 320-480 km (200-300 mi) of range per charge.[87] Lithium is also less expensive ... "Lithium-ion battery costs will still be about $400/kW⋅h by 2020". green.autoblog.com. Retrieved 1 February 2014.. ...
Reactive ion etching (RIE)[edit]. Main article: Reactive-ion etching. In reactive-ion etching (RIE), the substrate is placed ... Ion track technology[edit]. Ion track technology is a deep cutting tool with a resolution limit around 8 nm applicable to ... Ion beam lithography[edit]. It is known that focused-ion beam lithography has the capability of writing extremely fine lines ( ... A plasma is struck in the gas mixture using an RF power source, which breaks the gas molecules into ions. The ions accelerate ...
ions and [ClO. 4]−. ions. In such cases, the condensed formula only need be complex enough to show at least one of each ionic ... Ions in condensed formulas[edit]. For ions, the charge on a particular atom may be denoted with a right-hand superscript. For ... ion. Each polyatomic ion in a compound is written individually in order to illustrate the separate groupings. For example, the ... Here (NH3)6 indicates that the ion contains six [ammine,NH3 groups], and [ ] encloses the entire formula of the ion with charge ...
Ion Torrent semiconductor sequencing[edit]. Main article: Ion semiconductor sequencing. Ion Torrent Systems Inc. (now owned by ... Ion semiconductor (Ion Torrent sequencing). up to 600 bp[73]. 98%. up to 80 million. 2 hours. $1. Less expensive equipment. ... This causes the release of a hydrogen ion that triggers a hypersensitive ion sensor, which indicates that a reaction has ... This method of sequencing is based on the detection of hydrogen ions that are released during the polymerisation of DNA, as ...
Ion channel function[edit]. Each AMPAR has four sites to which an agonist (such as glutamate) can bind, one for each subunit.[5 ... Mayer, M. L. (2005). "Glutamate receptor ion channels". Current Opinion in Neurobiology. 15 (3): 282-288. doi:10.1016/j.conb. ... Here, A→I editing alters the uncharged amino acid glutamine (Q) to the positively charged arginine (R) in the receptor's ion ... NMDARs, on the other hand, do not open directly because their pores are occluded at resting membrane potential by Mg2+ ions. ...
ions. The ion produced by removing the electron from a deuterium atom is known as a deuteron, not a proton. Likewise, removing ... In chemistry, the term proton refers to the hydrogen ion, H+. . Since the atomic number of hydrogen is 1, a hydrogen ion has no ... In aqueous solution, it forms the hydronium ion, H3O+, which in turn is further solvated by water molecules in clusters such as ... Wilhelm Wien in 1898 identified the hydrogen ion as particle with highest charge-to-mass ratio in ionized gases.[11] ...
Metal ion binding[edit]. Beyond the iron-sulfur proteins, many other metal cofactors in enzymes are bound to the thiolate ...
Linear quadrupole ion trap[edit]. A linear quadrupole ion trap is similar to a quadrupole ion trap, but it traps ions in a two ... Here F is the force applied to the ion, m is the mass of the ion, a is the acceleration, Q is the ion charge, E is the electric ... Ion traps[edit]. Three-dimensional quadrupole ion trap[edit]. Further information: quadrupole ion trap ... Cylindrical ion trap[edit]. The cylindrical ion trap mass spectrometer (CIT) is a derivative of the quadrupole ion trap where ...
Small molecules and ions[edit]. The JT distortion of small molecules (or molecular ions) is directly deduced from electronic ... Peierls theorem, which states that a one-dimensional equally-spaced chain of ions with one electron per ion is unstable, has ... O'Brien, M. C. M. (1964). "Dynamic Jahn-Teller Effect in Octahedrally Co-ordinated d9 Ions". Proc. R. Soc. A. 281 (1384): 323- ... Bleaney, B.; Bowers, K. D. (1952). "The Cupric ion in a Trigonal Crystalline Electric Field". Proc. R. Soc. A. 65 (392): 667- ...
Ion implantation[edit]. Accelerating carbon ions under an electrical field into a semiconductor made of thin Ni films on a ... Producing graphene via intercalation splits graphite into single layer graphene by inserting guest molecules/ions between the ... and Nitronium Ion-Enabled Rapid and Direct Production of Highly Conductive Low-Oxygen Graphene". Journal of the American ... "Wafer-scale synthesis of multi-layer graphene by high-temperature carbon ion implantation". Applied Physics Letters. 107 (3): ...
... may be obtained by 1) addition of coloring ions,[1][2] by 2) precipitation of nanometer sized ...
Single-ion anisotropy[edit]. In crystals, spin-orbit coupling is responsible for single-ion magnetocrystalline anisotropy which ... Thus, single-ion anisotropy can couple an external electric field to spins of magnetically ordered compounds. ... This interaction depends on details of the crystal structure such as the bond length between magnetic ions and the angle formed ... As the strength of symmetric exchange depends on the relative position of the ions, it couples spins to collective lattice ...
Ion exchange SPE[edit]. Ion exchange sorbents separate analytes based on electrostatic interactions between the analyte of ... For ion exchange to occur, both the stationary phase and sample must be at a pH where both are charged. ...
Ion exchange[edit]. In 1998 Calgon Carbon came out with their Ion Separator (ISEP) product line, which uses a continuous ion ... At that point the company launched two new products: ISEP for perchlorate removal using a continuous ion exchange system, and ... Since then the company has manufactured ion exchange products for applications such as the recovery of precious metals, removal ... or ion exchange technology, and the company is the largest producer of granular activated carbon (GAC) in the world.[2] The ...
Immobilized metal ion affinity chromatography[edit]. Immobilized metal ion affinity chromatography (IMAC) is based on the ... For elution, an excess amount of a compound able to act as a metal ion ligand, such as imidazole, is used. GST has an affinity ... Many naturally occurring proteins do not have an affinity for metal ions, therefore recombinant DNA technology can be used to ... This technique works by allowing proteins with an affinity for metal ions to be retained in a column containing immobilized ...
Once the ion beam has ionized target sample atoms, the sample ions are recoiled toward the detector. The beam ions are ... For heavier ions in elastic recoil detection analysis, if m2/m1 ,,1, all recoiling ions have similar velocities.[15] It can be ... For the impinging ion, length of the incoming path L1 is given by :. L. 1. =. x. cos. ⁡. θ. 1. {\displaystyle L_{1}={\frac {x ... Depending on the kinetics of the ions, cross section area, and the loss of energy of the ions in the matter, Elastic Recoil ...
Therefore, the nitrite ion is a Lewis base. Moreover, it can act as an ambidentate ligand towards a metal ion, donating a pair ... The nitrite ion[edit]. Nitrite salts[edit]. Sodium nitrite is made industrially by passing "nitrous fumes" into aqueous sodium ... The nitrite ion, which has the chemical formula NO−. 2, is a symmetric anion with equal N-O bond lengths. Upon protonation, the ... The nitrite ion is an ambidentate ligand, and is known to bond to metal centers in at least five different ways.[1] Nitrite is ...
Ions can be metals, non-metals or polyatomic ions. Therefore, the name of the metal or positive polyatomic ion is followed by ... Polyatomic ions: NH+. 4 ammonium. H. 3O+. hydronium. NO−. 3 nitrate. NO−. 2 nitrite. ClO−. hypochlorite. ClO−. 2 chlorite. ClO− ... See polyatomic ion for a list of possible ions. For cations that take on multiple charges, the charge is written using Roman ... Positively charged ions are called cations and negatively charged ions are called anions. The cation is always named first. ...
When there are unequal concentrations of an ion across a permeable membrane, the ion will move across the membrane from the ... An example of passive transport is ion fluxes through Na+, K+, Ca2+, and Cl− channels. These ions tend to move down their ... An example of active transport of ions is the Na+-K+-ATPase (NKA). NKA catalyzes the hydrolysis of ATP into ADP and an ... Ions also carry an electric charge that forms an electric potential across a membrane. If there is an unequal distribution of ...
is the electric charge of the ions,. Z. e. {\displaystyle Z_{e}}. and Z. p. {\displaystyle Z_{p}}. the valences corresponding ... Forces on ions in an electrical field[edit]. Two forces affect ionized atoms in a conductor: 1) The direct electrostatic force ... This causes the ion to move from its original position. Over time this force knocks a significant number of atoms far from ... Since the metal ions in these regions are bonded more weakly than in a regular crystal lattice, once the electron wind has ...
... ion[edit]. See also: Hydrogen anion. Free hydride anions exist only under extreme conditions and are not invoked for ... Protide, deuteride, and tritide are used to describe ions or compounds, which contain enriched hydrogen-1, deuterium or tritium ... Aside from electride, the hydride ion is the simplest possible anion, consisting of two electrons and a proton. Hydrogen has a ... The low electron affinity of hydrogen and the strength of the H-H bond (∆HBE = 436 kJ/mol) means that the hydride ion would ...
The low atomic weight and small size of its ions also speeds its diffusion, suggesting that it would make an ideal material for ... Winter, Martin; Barnett, Brian; Xu, Kang (30 November 2018). "Before Li Ion Batteries". Chemical Reviews. 118 (23): 11433-11456 ... The earthenware barrier is porous, which allows ions to pass through but keeps the solutions from mixing. ... The use of a porous barrier allows ions to pass through but keeps the solutions from mixing. ...
Potassium ions usually cause less error than sodium ions. *Acidic error range - at very high concentration of hydrogen ions ( ... Because of the ion-exchange nature of the glass membrane, it is possible for some other ions to concurrently interact with ion- ... A glass electrode is a type of ion-selective electrode made of a doped glass membrane that is sensitive to a specific ion. The ... where E is the emf, E0 the standard electrode potential, z the ionic valency including the sign, a the activity, i the ion of ...
Ion-assisted deposition[edit]. In ion-assisted deposition (IAD), the substrate is exposed to a secondary ion beam operating at ... Ion-beam sputtering (IBS) is a method in which the target is external to the ion source. A source can work without any magnetic ... Denoting the fluxes of the arriving ions and atoms by Ji and Ja, it turned out that the magnitude of the Ji/Ja ratio plays a ... Ion-beam sputtering[edit]. A magnetron sputter gun showing the target-mounting surface, the vacuum feedthrough, the power ...
Ion irradiation[edit]. Ion irradiation means in general using particle accelerators to shoot energetic ions on a material. Ion ... Ion implantation[edit]. Main article: Ion implantation. Ion irradiation is routinely used to implant impurities atoms into ... implantation is a variety of ion irradiation, as is swift heavy ions irradiation from particle accelerators induces ion tracks ... This process, usually known as ion implantation, is an important step in the manufacture of silicon integrated circuits. ...
Metal ion transport and storage[edit]. This topic covers a diverse collection of ion channels, ion pumps (e.g. NaKATPase), ... Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-1_8. ISBN 978-94-007-5560-4.. CS1 maint: Extra text: ... Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-10_10. ISBN 978-94-007-5560-4.. CS1 maint: Extra text: ... The most important ions are sodium, potassium, calcium, magnesium, chloride, phosphate, and bicarbonate. The maintenance of ...
Metal ions[edit]. Further information: Metalloprotein. Metal ions are common cofactors.[10] The study of these cofactors falls ... A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's activity. Cofactors can be ... Cofactors can be subclassified as either inorganic ions or complex organic molecules called coenzymes,[1] the latter of which ... This often replaces the need for an external binding factor, such as a metal ion, for protein function. Potential modifications ...
Redox chemistry - the ferrocenium ion[edit]. Main article: Ferrocenium. Ferrocene undergoes a one-electron oxidation at around ... ions. Dihydrofulvalene is produced by radical-radical recombination while the iron(II) reacts with the Grignard reagent to form ...
LABORATORY OF MASS SPECTROMETRY AND GASEOUS ION CHEMISTRY *Research. *Lab Members. *Publications ...
Ion Channel Modulators Market research report covers detailed information on Global Ion Channel Modulators Market Size, Share, ... Ion channel modulator which is also called as channel modulators is a type of drug that modulates the ion channel. Ion channel ... Ion channel modulator is a key filter for safety pharmacology. Ion channel modulator is widely been used in drug discovery for ... Ion Channel Modulators Market: Segmentation. The global ion channel modulators market can be segmented on the basis of product ...
Polyhalogen ions are a group of polyatomic cations and anions containing halogens only. The ions can be classified into two ... The polyhalogen ions always have the heaviest and least electronegative halogen present in the ion as the central atom, making ... The [I3Cl2]+ and [I3Br2]+ ions have a trans-Z-type structure, analogous to that of [I5]+. The polyiodide ions have much more ... and heteropolyhalogen ions with more than one type of halogen. Numerous polyhalogen ions have been found, with their salts ...
Borenium ions can also be made through other methods such as the addition of base to a dicoordinate borinium ion or by ... Boronium ions have the formula [L2BR2]+ (L = Lewis base). Boronium ions are tetrahedral and coordinatively saturated. A well- ... Being electron-deficient, boranylium ions form adducts with Lewis bases. Boranylium ions have historical names that depend on ... A number of borenium ions have been structurally characterized through x-ray crystallography. The structures of borenium ions ...
Ions was voted best player of the league by other players at the end of the season. On 11 August 2016, Ions agreed to move on ... William Greenwell Ions (born 11 March 1994) is an English professional footballer who most lately played for SJK. Ions was born ... "Billy Ions siirtyy PS Kemistä SJK-paitaan" (in Finnish). SJK. Retrieved 11 August 2016. "B.Ions". soccerway.com. Soccerway. ... After being released by Leeds United, Ions joined the Nike Academy. He started his professional career with PS Kemi. Ions, born ...
Ions with a positive charge are called cations. Ions with a negative charge are called anions. ... An ion is an atom or group of atoms that has an electric charge. ... Ions with a positive charge are called cations. Ions with a ... Ions can be created using radiation such as x-rays. Ionizing radiation is often used to diagnose or treat a medical condition. ... Ion. Tabers Medical Dictionary, 23rd ed., F.A. Davis Company, 2017. Tabers Online. www.tabers.com/tabersonline/view/Tabers- ...
Ion Barbu (Romanian pronunciation: [iˈon ˈbarbu], pen name of Dan Barbilian; 18 March 1895 -11 August 1961) was a Romanian ... Ion Barbu from Intitutul National de Cercetare, Romania. *^ Boskoff, Wladimir G.; Suceavă, Bogdan (2007). "Barbilian spaces: ... He attended the Ion Brătianu High School in Piteşti and the Gheorghe Lazăr High School in Bucharest. During that time, he ... Ion Barbu died in Bucharest in 1961, and is buried at Bellu Cemetery. ...
The dissociative recombination of molecular ions with electrons plays a central role in the physics and chemistry of ionized ... D. Smith and N.G. Adams in Physics of Ion-Ion and Electron-Ion Collisions (eds. F. Brouillard and J. Wta. McGowan) (NATO ASI, ... P. Brouillard and W. Claeys in Physics of Ion-Ion and Klectron Ion Collisions (eds. F. Brouillard and J. Wm. McGowan), (NATO ... S.L. Guberman, in Physics of Ion-Ion and Electron-Ion Collisions (eds. F. Brouillard and J. Wm. McGowan) (NATO ASI Raddeck, ...
... an unusual property of quantum physics called entanglement involves illuminating two pairs of beryllium ions (charged atoms) ... "If someone comes up with an interface for efficiently transferring information from ions to photons, then ions could be used ... a mass-producible ion trap. Ions are among the most promising of a dozen or so candidates for quantum bits (qubits) to store, ... Then the first pair of ions was measured, and the results were used as an indication of whether the second pair (unmeasured, ...
They reduce the influx of calcium ions through the cell membrane, which normally occurs when the cell is depolarized. This ... Other articles where Calcium ion is discussed: cardiovascular drug: Heart rate: In the mid-1970s the calcium channel blockers, ... It also releases calcium ions when the muscle cell is triggered by nerve stimuli, resulting in muscle contraction. In this way ... They reduce the influx of calcium ions through the cell membrane, which normally occurs when the cell is depolarized. This ...
Ions. We sleep in sleeping bags on the beach, so in order to get close to you I have to slip out of mine first, then slip you ...
Purchase Ions, Cell Proliferation, and Cancer - 1st Edition. Print Book & E-Book. ISBN 9780121230500, 9781483277486 ... Monovalent Ion Fluxes, Cyclic Nucleotides, and the Stimulation of DNA Synthesis in Quiescent Cells. Section III: Divalent Ions ... Ions, Cell Proliferation, and Cancer present the credibility of ions as specific regulators of cell proliferation. This book ... Ion-Selective Microelectrodes and Fluorescent Probes for Measurement of Intracellular Ion Activities. Intracellular Calcium ...
... and use of lithium-ion batteries. Based on a solid foundation of long-term research work, this … - Selection from Lithium-Ion ... Lithium-Ion Batteries: Fundamentals and Applications offers a comprehensive treatment of the principles, background, design, ... Lithium-Ion Batteries: Fundamentals and Applications delivers a systematic overview of lithium-ion batteries, from physical ... 1.3 Principle of Lithium-Ion Batteries * 1.4 Some Requirements for Materials of Lithium-Ion Batteries * 1.4.1 Requirements for ...
The chapter is a review covering the most important aspects of fibrous ion exchangers: syntheses, physical chemical properties ... Shimizu H (1993) Development of ion-exchange technology in Japan, part III. J Ion Exch 4(2):2-19Google Scholar ... Soldatov VS (2008) Syntheses and the main properties of FIBAN fibrous ion exchangers. Solv Extract Ion Exch 26(5):457-513Google ... In: Abe M, Kataoka T, Suzuki T (eds) Proceedings of the international conference on ion exchange. New developments in ion ...
Buy WRATH Aeon of Ruin + Ion Fury Complete Your Set BUNDLE (?) Includes 2 items: Ion Fury, WRATH: Aeon of Ruin ... Bombshell and Ion Fury are registered trademarks of 3D Realms. The Bombshell Character design, the Bomb and related logos are ... Ion Fury laughs at the idea of mandatory checkpoints and straight paths through shooting galleries. But, just because this is a ...
Positively charged ions are called cations; negatively charged ions, anions. Ions are formed by the addition of electrons to, ... Ion, any atom or group of atoms that bears one or more positive or negative electrical charges. ... or the removal of electrons from, neutral atoms or molecules or other ions; ... Positively charged ions are called cations; negatively charged ions, anions. Ions are formed by the addition of electrons to, ...
Medium Energy Ion Scattering (MEIS). In contrast to low energy ion scattering, medium energy ion scattering tends to use H+ or ... Ion Scattering Ion scattering techniques operate across a large energy range, of 1keV to , 10MeV, each with different benefits ... Low Energy Ion Scattering (LEIS). The use of low energy ions has two advantages for surface studies, high cross-sections for ... Schematic diagram of ion-surface atom binary collision model.. With a monoenergetic ion beam, and knowledge of , and , ...
Created by Monica Z. Bruckner, Montana State University What is Ion Chromatography? Ion chromatography is used for water ... Ion chromatographs are able to measure concentrations of major anions, ... ... Ion Chromatography. Created by Monica Z. Bruckner, Montana State University. What is Ion Chromatography?. Ion chromatography is ... As an ion extraction liquid, known as eluent, runs through the column, the absorbed ions begin separating from the column. The ...
South Africa in 2018 we are glad to invite you for the second ION Africa Conference in Lome, Togo. This Conference will be held ...
What ions cause hardness in water?. Class practical. Hardness. in water indicates an inability to form a lather. with soap ... Practical chemistryExperiment & investigationPractical investigationsTeaching sequences/lesson plansTypes of ion: cationsTypes ... What ions cause hardness in water? Description. In this experiment the effect of dissolved salts, containing several different ... The calcium, magnesium and iron(II) ions cause hardness, that is they stop the lathering that should be apparent in the ...
Transparent lithium-ion batteries. Yuan Yang, Sangmoo Jeong, Liangbing Hu, Hui Wu, Seok Woo Lee, and Yi Cui ... Li-ion batteries with different transparencies were fabricated. For example, a full cell with an energy density of 10 Wh/L, ... 1999) Electrochemical study of Li4Ti5O12 as negative electrode for Li-ion polymer rechargeable batteries. J Power Sources 81-82 ... 2E shows an optical image of an assembled transparent Li-ion battery with two electrodes and a gel electrolyte membrane in ...
Ion iốt (vi); iodide ion (en); يوديد (ar); 碘化物 (zh-hans); İyodür (tr) অ্যানায়ন (bn); anion (fr); Lodoz eta beste elementu ... Media in category "Iodide ion". The following 2 files are in this category, out of 2 total. ... Ion iodure (fr); Jodiid (et); jon jodkowy, jodek (pl); Jodiden (nl); иодид, йодиды (ru); Jodidjon (sv); Jodid, Iodid, Jodide ( ... Retrieved from "https://commons.wikimedia.org/w/index.php?title=Category:Iodide_ion&oldid=306079297" ...
Media in category "Phenoxide ion". The following 7 files are in this category, out of 7 total. ... Phenol ion, Phenoxy ion (en); fenolan (pl) ... Category:Phenoxide ion. From Wikimedia Commons, the free media ... Retrieved from "https://commons.wikimedia.org/w/index.php?title=Category:Phenoxide_ion&oldid=357331753" ...
HYDROGEN-ION WAVE FUNCTION. V. Guillemin Jr. and C. Zener. PNAS April 15, 1929 15 (4) 314-318; https://doi.org/10.1073/pnas. ...
The study of ion channels is called electrophysiology, and is described in this article. ... Ion channels are imperative to the normal functioning of the cell. ... Ion channels are proteins embedded in the cell membrane which control the bidirectional movement of charged species called ions ... Subsequently, the movement of ions slows as the negative charge will attract ions back towards their starting side, thereby ...
Lights, camera, 802.11ax-ion!. Marvell claims itll have the first chipsets for new 10G WiFi ready for products in H2 2018. By ...
Defect Structure and Oxide Ion Conduction of Potassium Ion Substituted CaWO₄ Takai Shigeomi , Shitaune Shinya , Sano Toshifumi ... A multiple-energy implantation of oxygen ions into KNbO_3 is performed using energies of 200, 400, and 600 keV (each ion ... indicating that oxide ion conduction is associated with the formed oxide ion vacancy. … ... Reaction and Immobilization of Lead Ions in Magnesium Phosphate Cement Using Dolomite as Raw Material [in Japanese] 坂井 悦郎 , 茂木 ...
including IONS earnings per share estimates and analyst recommendations. ...
hydrogen ion - H1+. If a subscript is included a space will be put between the subscript and the charge. Ex. phosphate ion - ... Ion questions - the charge comes after the subscripts, it will be the last number that you see. Ex. ... Ion questions - the charge comes after the subscripts, it will be the last number that you see. Ex. hydrogen ion - H1+. If a ... phosphate ion - PO4 3- If you are given and element symbol, give its name, give its name and its root(Latin, Greek, or German ...
... This example shows the impact of temperature on a 7.2 V, 5.4 Ah, Lithium-Ion ... This demo illustrates the effect of temperature on the performance of a 7.2 V, 5.4 Ah Lithium-Ion battery model. The model ( ... 3. Cong Zhu, Xinghu Li, Lingjun Song, Liming Xiang, Development of a theoretically based thermal model for lithium ion battery ... The demonstration shows the performance of the temperature dependent Lithium-Ion battery model (Battery A) when the ambient ...
  • The use of alkali metal ions (ALCISS [1]}, which have a reduced ionisation probability), detection of neutrals and ions (NICISS [1]), both of which are operated in a time-of-flight (TOF) mode. (warwick.ac.uk)
  • Speaking last month at the Bioelectromagnetics Society in San Antonio in Texas, Valeri Lednev, a biophysicist at the Soviet Institute of Biological Physics in Puschino, proposed that a weak oscillating magnetic field could loosen the bonds between metal ions and some proteins in the body. (newscientist.com)
  • With positively charged metal ions, this goal is often achieved with chelate ligands, organic molecules that tightly grab hold of the ions. (innovations-report.com)
  • Toxicity of metal ions to alveolar macrophages. (cdc.gov)
  • The integrity of AM cell membranes was not affected in 90 percent of cells by high concentrations of metal ions. (cdc.gov)
  • Heavy metal ions are easily assimilated by a human organism and even when present in low concentrations can cause serious health problems. (hindawi.com)
  • Name and write the formulas for common transition metal ions. (frostburg.edu)
  • A wide range of molecules are available that modulates the ion channel activity. (factmr.com)
  • Also, in a biological environment, the calcium ion would be surrounded by a tight shell of water molecules that would alter its cyclotron frequency anyway. (newscientist.com)
  • Ions-charged atoms or molecules-play an important role in nature, in our bodies as well as for science and technology. (innovations-report.com)
  • This question will be answered, or better to say, try to be answered during the 2nd International Conference on Pollutant Toxic Ions and Molecules, PTIM2017 that will be held in November 2017 in Caparica, Portugal. (rsc.org)
  • Now they have added the protein to a layer of lipid molecules, enabling them to measure the ion currents directly. (innovations-report.com)
  • However, a very tiny percentage of those molecules have broken up into hydrogen ions (H+) and hydroxide ions, (OH-), as illustrated in the figure. (horiba.com)
  • In contrast, the so-called outer ion atmosphere consists of positive ions separated by at least one layer of water molecules from the phosphate groups. (eurekalert.org)
  • When CuCrSe 2 is heated above 190 degrees Fahrenheit, its copper ions fly around inside the layers of chromium and selenium about as fast as liquid water molecules move," said Olivier Delaire, associate professor of mechanical engineering and materials science at Duke and senior author on the study. (eurekalert.org)
  • In chemistry, hydrogen ions don't tend to exist on their own but preferentially bond to water molecules (assuming that's what's producing them). (physicsforums.com)
  • Ions are atoms or molecules that have gained or lost an electron. (spiritualityhealth.com)
  • Negative ions are found in abundance wherever air molecules are constantly breaking apart due to sunlight, radiation, moving air, or rushing water: the pounding surf at the beach, a waterfall, a lightning storm. (spiritualityhealth.com)
  • Applying a voltage across the electrodes makes electrons in the air collide with oxygen and nitrogen molecules, stripping them of electrons and creating positively charged ions. (technologyreview.com)
  • The ions move toward the negatively charged cathode, dragging surrounding air molecules with them and creating a breeze. (technologyreview.com)
  • Neurons have a negative concentration gradient, meaning the concentration of positively charged ions outside the cell is greater than that inside the cell, which leads to a separation of charge across the membrane. (news-medical.net)
  • The positively charged ions used at GSI are gained by stripping electrons off the shell of the atom. (gsi.de)
  • A positive ion is positively charged because it has more protons than electrons, while a negative ion is negatively charged because it has more electrons than protons. (spiritualityhealth.com)
  • Polyhalogen ions are a group of polyatomic cations and anions containing halogens only. (wikipedia.org)
  • Ions with a negative charge are called anions. (medlineplus.gov)
  • negatively charged ions, anions . (britannica.com)
  • negative ions, or anions, are formed by the gain of electrons. (dictionary.com)
  • Process for improving the plant growth with the aid of ion exchanger fertilizers, comprising adding to the growth medium weakly basic anion exchangers which are charged with anionic chelate complexes of micronutrient cations and macronutrient and micronutrient anions to the extent of at least 60% of their total capacity together with weakly acid cation exchangers charged with nutrient cations to the extent of at least 60% of their total capacity. (freepatentsonline.com)
  • hydrogen ion - H1+. (quia.com)
  • As they report in the journal Angewandte Chemie , bridging hydrogen bonds are responsible for holding the chloride ion in place. (innovations-report.com)
  • The triazoles hold on to the chloride ion by means of bridging hydrogen bonds, which is amazing because it was previously assumed that hydrogen bonds were not strong enough to form a sufficiently stable bond between a halogen ion and a chelate complex. (innovations-report.com)
  • Later, observations with scientific satellites surprisingly revealed that oxygen, helium and hydrogen ions from the Earth's upper atmosphere leaked into space from regions near the Earth's poles, (see Figure 2). (esa.int)
  • Actually, it is determined by the concentration of hydrogen ions, the percentage of hydrogen ions contained in the solution. (horiba.com)
  • Actually, this balance of hydrogen ions and hydroxide ions determines the pH of the water. (horiba.com)
  • When the hydrogen ions outnumber the hydroxide ions, the solution is acidic. (horiba.com)
  • In this way, pH is determined by hydrogen-ion concentration. (horiba.com)
  • The concentration of hydrogen ions in any solution we are likely to encounter will range from 1 mol to 0.000001 mol per liter of solution. (horiba.com)
  • However, solutions with extremely low hydrogen-ion concentration could conceivably rack up a pretty long parade of zeros after the decimal point. (horiba.com)
  • Danish biochemist S.P.L. Sorensen was the first to use the pH system we know today, which defines inverse numbers of hydrogen-ion concentration shown in common logarithm as pH. (horiba.com)
  • This means, for example, that a hydrogen-ion concentration of a solution with a pH of 4 is 10-4mol/l, meaning it contains 0.0001 mol of hydrogen ions in a solution of 1 liter. (horiba.com)
  • In the same way, a solution with a pH of 5 contains 10-5mol/l of hydrogen ions, a solution with a pH of 6 contains 10-6mol/l of hydrogen ions, while the solution with a pH of 7 contains 10-7mol/l of hydrogen ions. (horiba.com)
  • You will notice that if you compare solutions with pH of 4 and pH of 7, the difference in pH is only 3, but the concentration of hydrogen ions with a pH of 7 is 1000 times as high as with a pH of 4.The following figure also shows the advantage of exponents, which can express large variations in value that range over many orders of magnitude. (horiba.com)
  • A single blue ball represents 10-7mol/L of hydrogen ions. (horiba.com)
  • Someone once said that a positive hydrogen ion in a solution is not just a proton. (physicsforums.com)
  • When queried he replied by explaining that a positive hydrogen ion in solution will have a relatively high charge density because of the small ionic radius. (physicsforums.com)
  • I can't see any difference: a proton and a positive hydrogen ion must be one and the same thing. (physicsforums.com)
  • Unless of course the positive hydrogen ion acquires some special quality while being in solution? (physicsforums.com)
  • Chlorite ions readily react with ions that have a positive charge of +1, such as hydrogen ions, to form ionic compounds such as chlorous acid, or HClO2. (reference.com)
  • The attractive force between positive and negative ions stabilizes the crystal. (sparknotes.com)
  • Negative ions are anything but negative when it comes to your health. (spiritualityhealth.com)
  • Recent studies suggest that breathing in air that is abundant in negative ions can have a big influence on your feelings of well-being. (spiritualityhealth.com)
  • So, what are negative ions and how do we gain exposure to them? (spiritualityhealth.com)
  • Getting out into nature, of course, is the most beautiful and refreshing way to get your dose of negative ions. (spiritualityhealth.com)
  • Peptide ions where the number of protons is no greater than as the number of arginine residues have the greatest slope, V 1/2 /(m/z) = 0.0482 (all slopes in units of V Da -1 e) with a correlation coefficient of R 2 = 0.983. (nist.gov)
  • For peptides where the number of protons is greater than the number of arginine residues, but not greater than the total number of basic residues (no mobile protons), the slope decreases to 0.0416 (R 2 = 0.978) for singly-charged ions, 0.0382 (R 2 = 0.952) for doubly-charged ions, 0.0361 (R 2 = 0.958) for triply-charged ions, and 0.0305 (R 2 = 0.848) for more highly charged ions. (nist.gov)
  • the resulting ions do not have the same number of protons as electrons. (coursera.org)
  • Ions can be either positively or negatively charged. (dictionary.com)
  • Pairs of negatively charged phosphate groups and positive magnesium ions represent a key structural feature of DNA and RNA embedded in water. (eurekalert.org)
  • An ionic bond is comprised of the electrostatic attraction of positively and negatively charges ions which holds them together. (sparknotes.com)
  • Advancement in molecular and structural biology coupled with screening technology has led to the development of novel ion channels modulators drugs. (factmr.com)
  • As expected from the fact that an electron is removed from the antibonding orbital when X2 is ionized to [X2]+, the bond order as well as the bond strength in [X2]+ gets higher, consequently the interatomic distances in the molecular ion is less than those in X2. (wikipedia.org)
  • The dissociative recombination of molecular ions with electrons plays a central role in the physics and chemistry of ionized systems. (springer.com)
  • A team of scientists from ASU's School of Molecular Sciences and the Biodesign Institute have recently published a study in Nature Communications that helps clarify the contributions to an ion channel's temperature - dependent activation. (news-medical.net)
  • In the molecular-level world of ion channels - passageways through membranes that carry signals in a cell's environment and allow it to respond - researchers have debated about the role of a small piece of the channel called a linker, says computational biophysicist Jianhan Chen at the University of Massachusetts Amherst. (news-medical.net)
  • Ion chromatography is a form of liquid chromatography, using ion-exchange resins to separate atomic and molecular ions for analysis. (intertek.com)
  • We used electrophysiological, molecular and cellular techniques to the study of ion channel activity. (javeriana.edu.co)
  • A deeper insight at the molecular level requires highly sensitive probes which allow for discerning the different ion geometries without disturbing them, and for mapping their dynamics on the ultrafast time scale of molecular motions. (eurekalert.org)
  • an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation (positive ion) , which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion (negative ion) , which is created by an electron gain and is attracted to the anode. (dictionary.com)
  • Ion chromatography is used for water chemistry analysis. (carleton.edu)
  • This ion chromatography machine can analyze water chemistry. (carleton.edu)
  • This volume presents the proceedings of the 1990 Advanced Study Institute entitled "Fundamentals of Gas Phase Ion Chemistry" held at Mont Ste. Odile , Alsace, France, 25th June -6th July, 1990. (google.com)
  • The Institute brought together over 100 physicists, physical and organic chemists working on a wide variety of topics with gas-phase ion chemistry as the common theme. (google.com)
  • This Advanced Study Institute was the fifth in a series of NATO-sponsored institutes devoted to various aspects of the physics and chemistry of gas phase ions. (google.com)
  • These are not only by-products of the click chemistry, they are essential for binding the chloride ion, which can comfortably nestle into the empty center of the large donut-shaped ring. (innovations-report.com)
  • Can you name the Chemistry Ions? (sporcle.com)
  • To delineate the thermodynamic and kinetic impact of the sub-nanometre-sized confines on the catalytic chemistry of hydronium ions, the kinetics and elementary steps of the dehydration of a secondary alcohol, cyclohexanol, in water and in pores of zeolite Beta (BEA) are explored. (nature.com)
  • In chemistry, a boranylium ion is an inorganic cation with the chemical formula BR+ 2, where R represents a non-specific substituent. (wikipedia.org)
  • What is Ion Chromatography? (carleton.edu)
  • Concentrations of organic acids can also be measured through ion chromatography. (carleton.edu)
  • How Does Ion Chromatography Work? (carleton.edu)
  • Ion chromatography, a form of liquid chromatography, measures concentrations of ionic species by separating them based on their interaction with a resin. (carleton.edu)
  • This schematic diagram of an ion chromatography run depicts how elution time correlates to output peak data. (carleton.edu)
  • The graphs on the upper right display typical data output from an ion chromatography run. (carleton.edu)
  • Most ion chromatography machines provide software that calculates this area, which users can convert to ppm or other quantity using calibration standard solutions. (carleton.edu)
  • Handbook of Ion Chromatography, Third, Completely Revised and Enlarged Edition. (carleton.edu)
  • For more information about ion chromatography applications, click here . (carleton.edu)
  • In this study, we measured trace ions contained in edible salts, and evaluated their types, processes and characteristics using ion chromatography (IC). (nii.ac.jp)
  • Besides Ion Chromatography his research interests are titrations, solid-phase extractions, capillary electrophoresis and analytical complexing reagents. (wiley.com)
  • He has authored or coauthored several scientific books, including Fritz and Gjerde's ""Ion Chromatography"", now in its 4th printing. (wiley.com)
  • Ion Chromatography (IC) analysis. (intertek.com)
  • Ion chromatography (IC) laboratories support analytical testing projects requiring separation and identification of components and trace materials. (intertek.com)
  • Many crystalline substances are composed of ions held in regular geometric patterns by the attraction of the oppositely charged particles for each other. (britannica.com)
  • Subsequently, the movement of ions slows as the negative charge will attract ions back towards their starting side, thereby countering movement down the concentration gradient. (news-medical.net)
  • Current in bio-electricity involves the movement of ions. (coursera.org)
  • An ion is an atom or group of atoms that has an electric charge. (medlineplus.gov)
  • Ion , any atom or group of atoms that bears one or more positive or negative electrical charges. (britannica.com)
  • In translating this concept to inorganic catalysts we have shown in recent preliminary experiments that zeolite pores are able to substantially increase the rate at which hydronium ions catalyse reactions 3 . (nature.com)
  • Their properties, methods of preparation, and applications are in many ways different from those of conventional ion exchange resins. (springer.com)
  • The aim of this study is to evaluate quantitatively the effectiveness of the ion exchange resins and activated carbon in tritium measurement. (nii.ac.jp)
  • These results suggested that proposed batch method involving ion exchange resins and activated carbon had negligible effect on tritium measurement. (nii.ac.jp)
  • An artistic rendition of the intriguing superionic crystalline structure of CuCrSe 2 , which has copper ions that move like liquid between solid layers of chromium and selenium, giving rise to useful. (eurekalert.org)
  • In a new study, scientists from Duke University, Oak Ridge National Laboratory (ORNL) and Argonne National Laboratory (ANL) probed one such superionic crystal containing copper, chromium and selenium (CuCrSe 2 ) with neutrons and X-rays to determine how the material's copper ions achieve their liquid-like properties. (eurekalert.org)
  • To probe the copper ions' behavior, Delaire and his colleagues turned to two world-class facilities: the Spallation Neutron Source at Oak Ridge and the Advanced Photon Source at Argonne. (eurekalert.org)
  • By pinging a large sample of powdered CuCrSe 2 made at Oak Ridge with powerful neutrons, the researchers got a wide-scale view of the material's atomic structure and dynamics, revealing both the vibrations of the stiff scaffold of chromium and selenium atoms as well as the random jumps of copper ions within. (eurekalert.org)
  • This allows the copper ions to flow throughout the otherwise solid crystal. (eurekalert.org)
  • of polyethersulfone on the physicochemical properties of the membranes and their capacity for removal of iron and copper ions from the liquid phase was studied. (hindawi.com)
  • The concentration of ions moving through the column at a particular time is represented by the height and the breadth of the peaks and can be correlated to the concentration of a particular species in the sample solution. (carleton.edu)
  • Ion concentrations can be calculated using the area under each peak, where a larger area correlates with a higher concentration of a particular ion species. (carleton.edu)
  • Gradient refers to a difference in the concentration of a substance (ion or charge) between two environments that are separated by a barrier. (news-medical.net)
  • Ions will passively move from an area of high to low concentration (i.e. down their gradient). (news-medical.net)
  • Eventually, this charge difference, called the electric potential difference, reaches a point at which the electrical force that pulls ions up against their concentration gradient is balanced with the force that drives them down. (news-medical.net)
  • The concentration of the hydronium ions, on proper corrections ( Supplementary Table 1 ), has been used to calculate the turnover frequencies (TOFs) reported in Table 1 for the H 3 PO 4 -catalysed dehydration ( Supplementary Fig. 1 ). (nature.com)
  • At a NaCl background ion concentration of 0.01 mol/L, synthesized layered titanate demonstrated an approximately thirty-fold higher maximum SrႳ) adsorption capability than an anatase precursor. (nii.ac.jp)
  • Most of the structures of the ions have been determined by IR spectroscopy, Raman spectroscopy and X-ray crystallography. (wikipedia.org)
  • These can all be classed as impact collision ion scattering spectroscopy (ICISS). (warwick.ac.uk)
  • More importantly, the principal reaction network of the zeolite BEA-catalysed dehydration established by in situ magic angle spinning 13 C NMR spectroscopy 9 in aqueous phase enables us to analyse in this contribution the role of the confines on the catalytic properties of hydronium ions. (nature.com)
  • Dimethylphosphate (DMP, (CH3O)2PO2-), an established model system for the DNA and RNA backbone, was prepared in liquid water with an excess of Mg2+ ions (Figure 2, top) and studied by nonlinear vibrational spectroscopy in the femtosecond time domain (1 fs = 10 to the power of -15 s). (eurekalert.org)
  • The ability of 2D-IR spectroscopy to characterize the short-ranged phosphate-ion interaction in solution provides a novel analytical tool that complements currently available structural techniques. (eurekalert.org)
  • In this context, magnesium (Mg2+) ions are particularly relevant as they not only stabilize the structure but also mediate the recognition of external binding partners and act as catalytic centers. (eurekalert.org)
  • N-heterocyclic carbenes (NHCs) can also be used to stabilize borenium ions through pi-conjugation, albeit acting as weaker pi-donors than neutral N-donors. (wikipedia.org)
  • Numerous polyhalogen ions have been found, with their salts isolated in the solid state and structurally characterized. (wikipedia.org)
  • It is probably vital that the binding sites in the structurally stable macrocycle are preorganized into the correct configuration so that the chelator does not have to rearrange itself around the ion before binding can occur, as is the case for open-chain chelators. (innovations-report.com)
  • All known sequences of subunits from neurotransmitter-gated ion-channels are structurally related. (ebi.ac.uk)
  • A number of borenium ions have been structurally characterized through x-ray crystallography. (wikipedia.org)
  • The use of low energy ions has two advantages for surface studies, high cross-sections for ion-atom interactions and higher neutralisation probabilities for noble gas ions due to reduced velocity. (warwick.ac.uk)
  • Linear or nearly linear triatomic polyhalides have weaker and longer bonds compared with that in the corresponding diatomic interhalogen or halogen, consistent with the additional repulsion between atoms as the halide ion is added to the neutral molecule. (wikipedia.org)
  • A calcium ion affected in this way in an organism would collide with another molecule in the cell before making even a fraction of one orbit. (newscientist.com)
  • Amar Flood and Yongjun Li at Indiana University (Bloomington, USA) have now synthesized a donut-shaped molecule that tightly and selectively takes chloride ions up into its center. (innovations-report.com)
  • Kw is called the ion product of water or dissociation constant of water. (horiba.com)
  • Synthetic methods for preparing borenium ions include halide abstraction, nucleophilic dissociation, and protic addition to aminoboranes. (wikipedia.org)
  • In this way, the sarcoplasmic reticulum helps regulate calcium ion concentrations in the cytoplasm of skeletal muscle cells. (britannica.com)
  • This book discusses as well the two widely applicable methods for measuring free concentrations of ions inside cells. (elsevier.com)
  • 2. The process of claim 1, wherein the weakly basic anion exchanger(s) and the weakly acid cation exchanger(s) are each charged with nutrient ions to the extent of at least 80% of their total capacity. (freepatentsonline.com)
  • The effects of metallic ions and solvents on the function of alveolar macrophages (AM) were studied. (cdc.gov)
  • The authors conclude that exposure to metallic ions and solvents is toxic to the AM of rats. (cdc.gov)
  • Furthermore, when ionic compounds are placed in water or other polar solvents they dissociate into their component ions. (sparknotes.com)
  • Get Lithium-Ion Batteries now with O'Reilly online learning. (oreilly.com)
  • Explore a preview version of Lithium-Ion Batteries right now. (oreilly.com)
  • Lithium-Ion Batteries: Fundamentals and Applications offers a comprehensive treatment of the principles, background, design, production, and use of lithium-ion batteries. (oreilly.com)
  • Lithium-Ion Batteries: Fundamentals and Applications delivers a systematic overview of lithium-ion batteries, from physical properties to manufacturing technologies. (oreilly.com)
  • This example shows the impact of temperature on a 7.2 V, 5.4 Ah, Lithium-Ion battery module. (mathworks.com)
  • This demo illustrates the effect of temperature on the performance of a 7.2 V, 5.4 Ah Lithium-Ion battery model. (mathworks.com)
  • The demonstration shows the performance of the temperature dependent Lithium-Ion battery model (Battery A) when the ambient temperature is varied from 20 degrees C to -20 degrees C and then to 0 degrees C. Battery B represents the case where the effect of temperature is neglected. (mathworks.com)
  • Nevertheless, spent batteries may also present an opportunity as manufacturers require access to strategic elements and critical materials for key components in electric-vehicle manufacture: recycled lithium-ion batteries from electric vehicles could provide a valuable secondary source of materials. (nature.com)
  • Here we outline and evaluate the current range of approaches to electric-vehicle lithium-ion battery recycling and re-use, and highlight areas for future progress. (nature.com)
  • Given that the environmental footprint of manufacturing electric vehicles is heavily affected by the extraction of raw materials and production of lithium ion batteries, the resulting waste streams will inevitably place different demands on end-of-life dismantling and recycling systems. (nature.com)
  • This research analyses the lithium-ion battery market for industrial applications in Europe and presents revenue forecasts, pricing analysis, market share analysis, trends and opportunities, and competitive overview for a time period of 2009 to 2017. (prweb.com)
  • The market is divided into six segments based on the applications for lithium-ion batteries. (prweb.com)
  • The European lithium-ion battery market has high growth prospects for industrial applications, specifically in the medical, tools and energy storage segments. (prweb.com)
  • 1. Growth prospects for lithium-ion batteries in large scale energy storage industry. (prweb.com)
  • 3. Growth opportunities for lithium-ion batteries in emerging industrial applications. (prweb.com)
  • This study analyses the demand for lithium-ion batteries for industrial applications across Europe. (prweb.com)
  • Lithium-ion batteries are used widely for consumer applications such as laptops, cameras, mobile phones, etc. (prweb.com)
  • However, with technology advancing and improving everyday, lithium-ion batteries are now making their way into the industrial market, which is dominated by technologies such as lead acid, nickel cadmium, and nickel metal hydride. (prweb.com)
  • The lithium-ion battery market is still very nascent, with a high potential for growth in Europe. (prweb.com)
  • This study contains revenue Forecast, growth opportunities, factors influencing market growth and competitive structure of the lithium-ion battery market in Europe for industrial applications. (prweb.com)
  • The study includes all chemistries of lithium-ion batteries along with lithium polymer batteries. (prweb.com)
  • The difference between lithium-ion and lithium-ion polymer is its construction in terms of the arrangement of electrodes and electrolyte. (prweb.com)
  • Hence, this study considers lithium-ion polymer as a type of lithium-ion battery. (prweb.com)
  • One unit of lithium-ion battery described in this study refers to a single cell of a nominal voltage rating in the range of X toX V. (prweb.com)
  • This study includes both lithium-ion and lithium polymer cells for units shipment analysis. (prweb.com)
  • 10 . The lithium-ion battery of claim 9 , wherein the third electrode is provided such that it is electrically isolated from the first electrode and the second electrode within the battery, when not selectively connected to the second electrode. (google.ca)
  • This report is part of a multi-phase research program sponsored largely by the Foundation's Property Insurance Research Group (PIRG) to develop guidance for the protection of lithium ion batteries in storage. (nfpa.org)
  • This report presents the results of Phase II of the project which is a comparative flammability characterization of common lithium ion batteries to standard commodities in storage. (nfpa.org)
  • A recent push to include lithium ion battery storage in NFPA 13 prompted this study. (nfpa.org)
  • Built-in lithium-ion battery with low self-discharge rate so the power tool is ready to use whenever you need it. (ikea.com)
  • Built-in rechargeable lithium-ion battery 3.6V/1.3 Ah. (ikea.com)
  • Lithium-ion batteries do not contain mercury, cadmium or lead. (ikea.com)
  • Are lithium-ion cells intrinsically safe? (cdc.gov)
  • A better understanding of such materials could lead to safer and more efficient rechargeable batteries than the current standard-bearer of lithium ion. (eurekalert.org)
  • Most commercial lithium ion batteries use a liquid electrolyte to transfer ions between the positive and negative terminals of the battery," Delaire said. (eurekalert.org)
  • This made Lithium-ion batteries (LIBs) today's most powerful energy storage devices, commonly used in portable electronic devices, stationary power sources, and electric vehicles. (zeiss.com)
  • FIXA cordless power tools run on lithium-ion batteries, which can be recharged about 500 times. (ikea.com)
  • Here we demonstrate an origami lithium-ion battery that can be deformed at an unprecedented high level, including folding, bending and twisting. (nih.gov)
  • A new compound of five tin atoms and one iron atom (FeSn 5 ) created at the CFN is another development along the road to higher capacity lithium-ion batteries for those vehicles of the future. (scienceblogs.com)
  • Compared to other types of rechargeable batteries, lithium-ion batteries weigh less, can store more electricity for longer periods of time, and can handle more cycles of use and recharging. (scienceblogs.com)
  • Lithium-ion batteries provide energy as electricity flows from an anode to the device being powered and then back to the battery's cathode. (scienceblogs.com)
  • Our team found that the practical capacity for anodes of FeSn 5 was 100 percent higher than the ideal capacity for anodes used in conventional lithium-ion batteries. (scienceblogs.com)
  • This performance surpasses the highest-performance lithium-ion batteries on the market today. (scienceblogs.com)
  • The iron used in the new compound is also non-toxic and less expensive than the cobalt currently used in high-performance lithium-ion batteries. (scienceblogs.com)
  • Then, we inserted the sample anode into a lithium-ion battery and tested the cell by running it through a series of cycles. (scienceblogs.com)
  • When our tests showed that the FeSn 5 anodes could lead to a lithium-ion battery with a significantly higher practical capacity, scientists Jianming Bai, Haiyan Chen, and Trevor Tyson used x-ray diffraction at the National Synchrotron Light Source to document the new material's crystal structure. (scienceblogs.com)
  • Neurotransmitter ligand-gated ion channels are transmembrane receptor-ion channel complexes that open transiently upon binding of specific ligands, allowing rapid transmission of signals at chemical synapses [ PMID: 1721053 , PMID: 1846404 ]. (ebi.ac.uk)
  • When you encounter ionic compounds in the context of organic reactions, they will almost always occur as free ions in solution. (sparknotes.com)
  • Ion channels may act as the site of action for GABA which is a fast acting neurotransmitter along with channels such as sodium, potassium and calcium. (factmr.com)
  • and of K content vs. PV were 0.905 and 0.714, respectively, indicating that potassium ions are important for expressing the pasting properties of lotus starch. (nii.ac.jp)
  • are small ions such as sodium ions or potassium ions or chloride ions. (coursera.org)
  • So called because ions move toward the electrode of opposite charge. (dictionary.com)
  • Glycine receptor, an inhibitory chloride ion channel composed of alpha and beta subunits [ PMID: 15383648 ]. (ebi.ac.uk)
  • Chloride ion has a negative charge. (coursera.org)
  • The Lewis dot structure of NaCl consists of a chloride ion surrounded by eight electron dots (four pairs) and a sodium ion bonded to that chlorine ion. (reference.com)
  • Ions with a positive charge are called cations. (medlineplus.gov)
  • As ions are charged, a net positive charge builds up on the side that they move to, and a net negative charge on the side that they moved away from. (news-medical.net)
  • The sodium ion has a positive charge because it loses an electron. (physicsforums.com)
  • 16. The ion beam source according to claim 1, further comprising means for applying a high potential between said needle-like tip and said cathode such that the needle-like tip takes a positive charge of a sufficient strength to ionize the substance to be ionized. (google.com)
  • The team discovered that a positive charge travels through the membrane: The membrane proteins do not transport the gas ammonia NH3 but rather the ammonium ion NH4+. (innovations-report.com)
  • Stabilization of the macromolecular structures of DNA and RNA requires a compensation of strong repulsive electric forces between the equally charged phosphate groups by ions of opposite, i.e., positive charge. (eurekalert.org)
  • Moreover, changes of macromolecular structure via dynamic folding processes are connected with a rearrangement of positive ions embedded in the surrounding water shell. (eurekalert.org)
  • Positive ions are arranged in different geometries around DNA and RNA: in so-called site-bound or contact-pair geometries, a positive ion is located in direct contact with an oxygen atom of a phosphate group. (eurekalert.org)
  • Best way to easily make positive ions? (physicsforums.com)
  • The sodium ion has a positive charge. (coursera.org)
  • Ions formed by the loss of an electron have a positive charge, and those formed by gaining an e. (reference.com)
  • A nucleophilic attack is a chemical process by which an electron-rich atom or nucleus rapidly forms a new bond with an electron-poor atom or positive ion. (reference.com)
  • A Natural Population Analysis treatment of many borenium ions show that the boron center does indeed carry a significant positive charge. (wikipedia.org)
  • They reduce the influx of calcium ions through the cell membrane, which normally occurs when the cell is depolarized. (britannica.com)
  • It also releases calcium ions when the muscle cell is triggered by nerve stimuli, resulting in muscle contraction. (britannica.com)
  • Many animal cells can perform a primary active transport of calcium out of the cell, developing a 10,000-fold gradient of that ion. (britannica.com)
  • The calcium, magnesium and iron(II) ions cause 'hardness', that is they stop the lathering that should be apparent in the distilled water and the other test-tubes. (rsc.org)
  • They found that the most effective frequency corresponded to the cyclotron resonance frequency for a particular ion, calcium, an extremely important metal in living systems, which is known to affect the behaviour of diatoms. (newscientist.com)
  • Unfortunately, this theory was shot down by several objections: first, the radius of the cyclotron orbit for the calcium ion, at one metre, is very large. (newscientist.com)
  • It considers what happens to a calcium ion bound in a calcium binding protein, calmodulin, when placed in static and oscillating magnetic fields. (newscientist.com)
  • With the aid of lasers and graphene, researchers may have developed a new type of sodium-ion battery that works better and could reduce the cost of battery technology by an order of magnitude. (extremetech.com)
  • Despite the seemingly ubiquitous use in organic conversion sequences, the dehydration of alcohols by hydronium ions in aqueous phase is surprisingly challenging, requiring reaction temperatures above 100 °C to occur at industrially acceptable rates 1 . (nature.com)
  • Borenium ions can be made in a number of different ways and are of interest for applications in organic synthesis and catalysis. (wikipedia.org)
  • This ion delivers the proton to what we consider H+ + (something else) reactions. (physicsforums.com)
  • Similar to the halide abstraction method, borenium ions can be made through abstraction of a hydride from a tetracoordinate boron complex. (wikipedia.org)
  • The final chapter deals with magnesium ion as the most abundant divalent action in living cells. (elsevier.com)
  • Ion channel are essential pore forming membrane proteins whereby some drugs may interact directly or indirectly that leads to change in electric signals and action potential across the membrane. (factmr.com)
  • Ion channels are proteins embedded in the cell membrane which control the bidirectional movement of charged species called ions across the impermeable cell membrane. (news-medical.net)
  • In mammals, Rhesus proteins regulate acid and ion balance in kidney and liver cells. (innovations-report.com)
  • The energy dependence of fragmentation in a collision cell was measured for 2100 peptide ions derived from the digestion of twenty four common proteins. (nist.gov)
  • Discrete polyiodides usually have a linear sequence of iodine atoms and iodide ions, and are described in terms of association between I2, I− and I− 3 units, which reflects the origin of the polyiodide. (wikipedia.org)
  • For compounds containing the iodide ion, see Category:Iodides . (wikimedia.org)
  • A chlorite ion consists of one chlorine atom covalently bonded to two oxygen atoms. (reference.com)
  • When an atom gains or loses an electron, it becomes an ion. (reference.com)
  • The transport of ions is essential to maintain electrophysiological balance on either side of the membrane, called osmotic balance, which is needed for signals to be transduced from their chemical (ion) form to a cellular response. (news-medical.net)
  • A release of neurotransmitters across a synaptic junction, causes Na + channels on the postsynaptic (recipient) neuron membrane to open so that Na+ ions flow from the extracellular environment into this downstream neuron. (news-medical.net)
  • It is an ion exchange membrane developed by utilizing the high coating technology cultivated over many years of photographic film. (fujifilm.com)
  • Removal of heavy metals such as copper, iron, cadmium or zinc is done from water solutions by different methods of separation including precipitation, coagulation, ion exchange, adsorption, and membrane technology [ 3 ]. (hindawi.com)
  • The electroless process proposed here opens possibility of the direct metal fabrication on ion exchange membrane surface. (nii.ac.jp)
  • During the 490th Brookhaven Lecture, Bjoern Schenke discussed theory that details the shape and structure of heavy ion collisions. (bnl.gov)
  • The QGP formed in heavy ion collisions lives only an incredibly short time, about 10 -23 fraction of a second. (weizmann.ac.il)
  • In general, the structures of most heteropolyhalogen ions and lower isopolyhalogen ions were in agreement with the VSEPR model. (wikipedia.org)
  • The polyiodide ions have much more complicated structures. (wikipedia.org)
  • This, in turn, makes it possible to observe much more sensitive and fine angular structures in the distribution of transmitted ions. (springer.com)
  • The structures of borenium ions generally have two short bonds and one longer bond which is characteristic of a dative bond. (wikipedia.org)
  • Indeed, thinner crystals provide better ways to manipulate the trajectories of very high-energy ions in particle accelerators. (springer.com)
  • It connects more than 2,500 researchers around the world with the data generated by millions of particle collisions taking place each second at Brookhaven Lab's Relativistic Heavy Ion Collider (RHIC, a DOE Office of Science User Facility for nuclear physics research), and the ATLAS experiment at the Large Hadron Collider in Europe. (bnl.gov)
  • He then describes his analysis of data from particle collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider to test his hypothesis. (bnl.gov)
  • During the 493rd Brookhaven Lecture, Anne Sickles discussed how physicists determine what happens before, during, and after individual particle collisions among billions at the Relativistic Heavy Ion Collider (RHIC). (bnl.gov)
  • This ion chromatograph displays data from a cation analysis of glacial waters. (carleton.edu)
  • Dehydration of cyclohexanol catalysed by dilute hydronium ions (dissociated from H 3 PO 4 ) leads solely to the formation of cyclohexene. (nature.com)
  • P. Brouillard and W. Claeys in Physics of Ion-Ion and Klectron Ion Collisions (eds. (springer.com)
  • S.L. Guberman, in Physics of Ion-Ion and Electron-Ion Collisions (eds. (springer.com)
  • During the 496th Brookhaven Lecture, Lijuan Ruan explained how she uses electron-positron tomography from quark-antiquark annihilations to study chiral symmetry, a characteristic that 'broke' to form 99 percent of the visible mass in the universe and is thought to be restored during ion collisions at the Relativistic Heavy Ion Collider. (bnl.gov)
  • During the 2014 Sambamurti Lecture, physicist Anne Sickles discussed how correlations between particles created during collisions at the Relativistic Heavy Ion Collider (RHIC) are being used to determine the properties of matter itself. (bnl.gov)
  • The chapter is a review covering the most important aspects of fibrous ion exchangers: syntheses, physical chemical properties, equilibria and kinetics of sorption processes, and possible and real fields of their applications. (springer.com)
  • Advantages and problems connected with fibrous ion exchangers are considered in the chapter. (springer.com)
  • Sorption of different substances from air and applications of fibrous ion exchangers for air purification from substances of different natures (acid, base, neutral substances, water vapors) is a most important field for their practical use. (springer.com)
  • Soldatov VS, Shunkevich AA, Sergeev GI (1988) Synthesis, structure and properties of new fibrous ion exchangers. (springer.com)
  • Soldatov VS, Elinson IS, Shunkevich AA (1994) Application of fibrous ion exchangers in air purification from acidic impurities. (springer.com)
  • Soldatov VS, Elinson IS, Shunkevich AA et al (1996) Air pollution control with fibrous ion exchangers. (springer.com)
  • Soldatov VS, Pawlowski L, Wasag H et al (1996) Prospects of fibrous ion exchangers in water pollution control. (springer.com)
  • 3. A process according to claim 1, wherein the highly charged weakly basic and weakly acid ion exchangers are employed in a ratio such that the amount of weakly acid groups is 10 to 90%, relative to the sum of weakly basic groups and weakly acid groups. (freepatentsonline.com)
  • The authors study the trajectories of high-energy ions, which pass through several radial rings of atomic strings before exiting the thin crystal. (springer.com)
  • An ion beam source characterized in that a needle-like tip is comprised of a carbide, a nitride, or a diboride of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb and Ta, a hexaboride of at least one element of rare earth metal elements of atomic numbers 57-70, or carbon. (google.com)
  • To obtain quantitative information about the species present at the surface of a material it is necessary to understand the interaction potentials, due to the effects of ion neutralisation and scattering cross-section. (warwick.ac.uk)
  • The elution time, or time it takes for the ion to move through the column, varies for each ion species as they elute from the column separately as the pH and/or ionic strength of the eluent is increased. (carleton.edu)
  • For example, LiCoO 2 and graphite, the most common cathode and anode in Li-ion batteries, are good absorbers even with a thickness less than 1 μm. (pnas.org)