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.
cation A positively charged ion. centrifugation A laboratory technique which involves the application of centrifugal force to ... Charge numbers for ions are denoted in superscript (e.g. Na+ indicates a sodium ion with a charge number of positive one). ... All molecules or ions with a free pair of electrons or at least one pi bond can act as nucleophiles, by which they are ... polyatomic ion A molecule composed of two or more covalently bonded atoms which collectively bear a net electric charge and ...
cathode ray cation A positively charged ion. Contrast anion. celestial mechanics Celsius scale A scale and unit of measurement ... invariant mass ion An atom or molecule in which the total number of electrons is not equal to the total number of protons, ... ionization The process of converting an atom or molecule into an ion by adding or removing charged particles such as electrons ... Molecules are distinguished from ions by having a net electric charge equal to zero. molecular physics A branch of physics that ...
A cation is a positively charged ion. The degree Celsius (°C) is a designation for specific temperatures on the Celsius scale ... Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. An ion-exchange ... A negatively charged ion; an ion that is attracted to the anode. An anode is an electrode through which electric current flows ... Hydride is the name given to the negative ion of hydrogen, H−. Aside from electride, the hydride ion is the simplest possible ...
doi:10.1016/s0040-4020(01)88362-9. Jorgensen, W. (1985). "Magnitude and origin of the .beta.-silicon effect on carbenium ions ... Lambert, J. (1990). "The Interaction with Silicon with Positively Charged Carbon". Tetrahedron. 46 (8): 2677-2689. ... the diazo compound 3 decomposes to the carbenium ion 5. In aprotic solvents, the diazo compound 3 decomposes to the carbene 7. ...
The net flow of positively charged ions is inward. The nAChR is a non-selective cation channel, meaning that several different ... Opening of the channel allows positively charged ions to move across it; in particular, sodium enters the cell and potassium ... positively charged ions can cross through. It is permeable to Na+ and K+, with some subunit combinations that are also ... As with all ligand-gated ion channels, opening of the nAChR channel pore requires the binding of a chemical messenger. Several ...
mobility of positively and negatively charged ions, N. {\displaystyle N}. : ion concentration, α. {\displaystyle \alpha }. : ... module of the ion charge, b. +. {\displaystyle b^{+}}. and b. −. {\displaystyle b^{-}}. : ... Small holes in cell membranes, called ion channels, are selective to specific ions and determine the membrane resistance. ... which is determined by the ratio of the concentration of ions N. {\displaystyle N}. to the concentration of molecules of the ...
Atoms that gain electrons make negatively charged ions (called anions). Atoms that lose electrons make positively charged ions ... Ions in crystal lattices of purely ionic compounds are spherical; however, if the positive ion is small and/or highly charged, ... However, the ions themselves can be complex and form molecular ions like the acetate anion or the ammonium cation. For example ... Larger negative ions are more easily polarized, but the effect is usually important only when positive ions with charges of 3+ ...
Oil Rig: Oxidation is loss; Reduction is gain (of electrons). Cations are positively (+) charged ions while anions are ... Ca+ion: The letter t in cation looks like a + (plus) sign. An anion is a negative ion. (Anegativeion ⇒ Anion). The t in cation ... An atom (or ion) whose oxidation number increases in a redox reaction is said to be oxidized (and is called a reducing agent). ... Cat ions are pawsitive AN OIL RIG CAT: At the ANode, Oxidation Involves Loss of electrons. Reduction Involves Gaining electrons ...
Elsewhere on the airframe, collectors attract these positively charged ions. As the ions travel toward the collectors, they ... It is claimed to be the first ion-propelled airplane. Ion-propelled aircraft without wings have existed since the 1960s. The ... Major de Seversky's Ion-Propelled Aircraft. 122. Popular mechanics. August 1964. pp. 58-61. "Radical Experimental Plane With No ... "Scientists at MIT Have Flown The First-Ever Solid-State Plane Powered by an Ion Drive". Science News Magazines. 21 November ...
... while leaving neutral ions virtually unaffected. Positively charged ions were found to accumulate in the membrane. Multi- ... Functionalized nanofibers obtained using nitro-oxidation have been found to be an excellent substrate to remove heavy metal ion ... Films constituted of negatively charged cellulose nanowhiskers could effectively reduce permeation of negatively charged ions, ... "An Organic Mixed Ion-Electron Conductor for Power Electronics". Advanced Science. 3 (2). doi:10.1002/advs.201500305. ISSN 2198- ...
Internal C=O bonds are found in positively charged oxonium ions. In furans, the oxygen atom contributes to pi-electron ...
Electrostatic ion acceleration. This is done dropping the positively charged ions towards negative plates. As the ions fall, ... drift of newly created fast ions in the magnetic field, collisions of fast ions with plasma ions and electrons by Coulomb ... The precursor beam could either be a positive-ion beam or a negative-ion beam: in order to obtain a sufficiently high current, ... In order to generate a sufficiently high negative-ion density and obtain a decent negative-ion beam current, caesium vapors are ...
... these oxygen ions possess an effective negative charge. The positively charged sodium ions provide partly covalent and partly ... In three-dimensional silica glass, the addition of sodium ions causes oxygen ions formed a bridge, ...
A carbocation (/ˌkɑːrboʊˈkætaɪən/) is an ion with a positively charged carbon atom. Among the simplest examples are the ... three in the carbenium ions and five in the carbonium ions. This nomenclature was proposed by G. A. Olah. Carbonium ions, as ... One textbook retains the older name of carbonium ion for carbenium ion to this day, and uses the phrase hypervalent carbonium ... Pittman Jr., Charles U.; Olah, George A. (1965). "Stable Carbonium Ions. XVII.1a Cyclopropyl Carbonium Ions and Protonated ...
Positively charged ions outside the cell experience a force towards the cathode. There is a flux of these ions outside the cell ... electric field may depolarize the cell near the cathodal side opening voltage-gated calcium channels and allowing calcium ions ...
Since the positively-charged ions also present in the ionosphere are orders of magnitude more massive, they are not as readily ... However, the electrons tend to remain close to the positively-charged ions. As a result, the distribution function of the ... However, it is important to note that the thermal behavior differs between electrons and ions. The ions are orders of magnitude ... The incoherent scatter signal allows measurement of electron density, ion temperature and electron temperatures, ion ...
... the resin is coated with positively charged counter-ions (cations). Anion exchange resins will bind to negatively charged ... Guide to Ion-Exchange Chromatography. Harvard Apparatus. p. 2. Guide to Ion-Exchange Chromatography. Harvard Apparatus. p. 3.. ... The negative ions in the salt solution (e.g. Cl−) compete with protein in binding to the resin. Second, the pH of the solution ... Proteins that bind to the positively charged resin are retained and can be eluted in one of two ways. First, the salt ...
These channels transport positively charged potassium ions into and out of cells. In heart muscle, the ion channels produced ... This disruption in ion transport alters the way the heart beats, increasing the risk of syncope, stroke, and sudden death.[ ... These mutations increase the activity of the channels, which changes the flow of potassium ions between cells. ...
Ions causing permanent hardness of water can be removed using a water softener, or ion-exchange column. Temporary hardness is ... Multivalent cations are positively charged metal complexes with a charge greater than 1+. Usually, the cations have the charge ... A common method for water softening involves the use of ion-exchange resins, which replace ions like Ca2+ by twice the number ... is principally caused by thermal decomposition of bicarbonate ions but also happens in cases where the carbonate ion is at ...
... positively charged ions. For simplicity, we ignore the motion and spatial distribution of the ions, approximating them as a ... Like the electric field of the nucleus is reduced inside an atom or ion due to the shielding effect, the electric fields of ... This region can be treated as a positively charged "screening hole". Viewed from a large distance, this screening hole has the ... This simplification is permissible since the electrons are lighter and more mobile than the ions, provided we consider ...
For example, most metal centers are positively charged ions which exist as salts. The counterion in the salt can affect the ... In order to allow efficient magnetic, metal ions should be bridged by small ligands allowing for short metal-metal contacts ( ... Partially filled d orbitals, either in the atom or ion, can hybridize differently depending on environment. This electronic ... Fromm, K. (2008). "Coordination polymer networks with s-block metal ions" (PDF). Coord. Chem. Rev. 252 (8-9): 856-885. doi: ...
Positively charged ions are called cations and negatively charged ions are called anions. The cation is always named first. ... Ions can be metals, non-metals or polyatomic ions. Therefore, the name of the metal or positive polyatomic ion is followed by ... See polyatomic ion for a list of possible ions. For cations that take on multiple charges, the charge is written using Roman ... of the metal ion is represented by a Roman numeral in parentheses immediately following the metal ion name. For example, in ...
This allows the flow of positive ions, such as sodium or calcium. The influx of positively charged ions depolarizes, or excites ... However, unlike AMPA receptors, external ions also bind to kainate receptors at the ion binding pocket on the extracellular ... When both the ligand and ion bind, the receptor undergoes a conformational change and the ion channel opens. ... Binding causes a conformational change that opens the receptor and allows for positively charged ions, Na+ and/or Ca2+ to enter ...
... disperses positively charged copper and silver ions into the water system. The ions bond ... The level of ions generated has been reported to be usually below EPA Safe Water Drinking Act Lead and Copper Rule AL for ... Over the long term, the presence of copper and silver ions destroy biofilms and slimes that can harbor Legionella, the bacteria ... The British Health and Safety Commission regulates U.K. ionization, advising regular system monitoring to ensure ions reach all ...
This frees the electron from the atom, and leaves a positively charged ion behind. There is an analogy with satellites orbiting ...
The hydride ion abstracts a hydrogen from the positively charged nitrogen, forming hydrogen gas. The ring nitrogen then pushes ... Hydride ion elimination In addition to the mechanism shown above, other pathways have been proposed for the elimination step. ... Ease of hydride elimination - Success of this reaction is also dependent on the ease at which the hydride ion leaves and the ... The mechanism above, loss of the hydride ion followed by abstraction of a proton, is supported by the fact that the nucleophile ...
This is brought about by positively charged sodium ions rapidly passing into the axon. desmosome A cell structure specialized ... ion An atom or molecule with a net electric charge due to the loss or gain of one or more electrons. ionic bond A type of ... biomolecule Molecules and ions that are present in organisms, essential to some typically biological process such as cell ... electrochemical gradient A gradient of electrochemical potential, usually for an ion that can move across a membrane. The ...
... where A and B are planes of hydroxide ions, and c those of Fe2+ (iron(II), ferrous) cations. In the green rust, some Fe2+ ... becomes positively charged. The anions then intercalate between those triple layers and restore neutrality. There are two basic ...
CEC is the ability to absorb positively charged nutrient ions (so high CEC is good). This means the substrate will hold ... It softens water by acting as an ion exchanger, it contains substances good for plants and for the reproductive health of ...
The trifluorooxonium cation is a hypothetical positively charged polyatomic ion with chemical formula OF+ 3. It is structurally ... equivalent to the hydronium ion where the hydrogen atoms surrounding the central oxygen atom have been replaced by fluorine, ...
... we get positively charged sodium ions moving from positive to negative and negatively charged chloride ions moving from ... There are also solid ion conductors, eg for lithium or sodium, but they are special materials and not metals. The main electric ...
Hence, positively charged ions (namely sodium ions) enter the photoreceptor, depolarizing it to about −40 mV (resting potential ... This leads to a decrease in the influx of calcium ions into the cell and thus the intracellular calcium ion concentration falls ... Reduction in cGMP allows the ion channels to close, preventing the influx of positive ions, hyperpolarizing the cell, and ... This pump is necessary to reset the initial state of the outer segment by taking the sodium ions that are entering the cell and ...
... leaving a positively charged metal surface and negatively charged water ions. The attraction between the charged metal and ... 4 ions.[66] The chemistry of alkali metal germanides, involving the germanide ion Ge4− and other cluster (Zintl) ions such as ... x ions.[66] Due to the basicity of the Se2− and Te2− ions, the alkali metal selenides and tellurides are alkaline in solution; ... 2 ion, where there is a single bond between the two oxygen atoms), superoxides (containing the O−. 2 ion), and many others. ...
Burlingame, California: Positively Filipino LLC. Retrieved August 25, 2018 - via Positively Filipino.. Floro L. Mercene (2007 ... 49 WPXL (Ion). *54 WUPL (MyNetworkTV). WWOZ,[199] the New Orleans Jazz and Heritage Station, broadcasts[200] modern and ...
The nitrogen atom features a lone electron pair that can bind H+ to form an ammonium ion R3NH+. The lone electron pair is ... 3) are the most common positively charged moieties in proteins, specifically in the amino acid lysine.[16] The anionic polymer ... N-H groups strongly interact with water, especially in ammonium ions. Consequently, the basicity of ammonia is enhanced by 1011 ... Most primary amines are good ligands for metal ions to give coordination complexes. Amines are alkylated by alkyl halides. Acyl ...
Ionisers use electrostatically charged plates to produce positively or negatively charged gas ions (for instance N2− or O2−) ... The Negative-Ion Myth (archive). Further reading[edit]. *. Fletcher, L.A.; Noakes, C.J.; Sleigh, P.A.; Beggs, C.B.; Shepherd, S ... An air ioniser (or negative ion generator or Chizhevsky's chandelier) is a device that uses high voltage to ionise ( ... Ions versus ozone[edit]. Ionisers are distinct from ozone generators, although both devices operate in a similar way. ...
For example, the colloidal particles are negatively charged and alum is added as a coagulant to create positively charged ions ...
... with a negatively charged end and a positively charged end. ...
... ion exchange interactions bind the DNA to the membrane due to the negative charge of the DNA and positive charge of the ... denaturation in an alkaline environment may improve binding of the negatively charged thymine residues of DNA to a positively ...
... an onium ion: HClO4 ⇌ H+ + ClO4− CH3COOH + H+ ⇌ CH3COOH2+ (onium ion) Since the CH3COOH2+ ion readily donates its proton to a ... It follows from these definitions that an acid may be either: an electrically neutral molecule, e.g. HCl, or a positively ... to a halide salt replaces the halide ion by an equivalent quantity of acetate ion, which is a strong base in acetic acid. 2R. ... The halide ions - chloride, bromide and iodide - are too weakly basic to react quantitatively with acetous perchloric acid. ...
When an atom loses an electron and thus has more protons than electrons, the atom is a positively charged ion or cation. When ... Main article: Ion. An ion is a charged species, an atom or a molecule, that has lost or gained one or more electrons. ... 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+ ...
Cosmic rays made up of charged nuclei heavier than helium are called HZE ions. Due to the high charge and heavy nature of HZE ... Alvarez, Luis; Compton, Arthur Holly (May 1933). "A Positively Charged Component of Cosmic Rays". Physical Review. 43 (10): 835 ... Spallation is also responsible for the abundances of scandium, titanium, vanadium, and manganese ions in cosmic rays produced ... In 1909, Theodor Wulf developed an electrometer, a device to measure the rate of ion production inside a hermetically sealed ...
... to absorption into cells and production of nano-channels that obstruct vital ion channels that ferry potassium and sodium ions ... Another study found that these respiratory symptoms were positively associated with exposure to water damaged homes, exposure ...
The charge on the left ring will attract negative charges in the water (ions) into the left-hand stream by the Coulomb ... When drops break off the end of that stream, they carry positive charge to the positively charged bucket, making that bucket ... Thus positive charges are attracted to the right-hand stream by the ring, and positive charge drips into the positively charged ... there is an electric current that flows in the form of positive or negative ions in the water of the supply lines. This is ...
The positively charged 235U ions are then attracted to a negatively charged plate and collected. ... and then ionized to positively charged ions. The cations are then accelerated and subsequently deflected by magnetic fields ... the principle of ion cyclotron resonance is used to selectively energize the 235U isotope in a plasma containing a mix of ions ... An ion-exchange process was developed by the Asahi Chemical Company in Japan that applies similar chemistry but effects ...
Protons (hydrogen ions) and neutrons begin to combine into atomic nuclei in the process of nuclear fusion. Free neutrons ... containing positively charged protons) are therefore electrically charged (+1 and +2 respectively). As the universe cools down ... the electrons get captured by the ions, forming electrically neutral atoms. This process is relatively fast (and faster for the ...
... positively charged ions) migrate. Cations are reduced (electrons are added) at the cathode, while metal atoms are oxidized ( ... and lithium-ion (Li-ion) cells. Li-ion has by far the highest share of the dry cell rechargeable market. NiMH has replaced NiCd ... developed by a team led by Lithium-ion (Li-Ion) inventor John Goodenough, "that could lead to safer, faster-charging, longer- ... Lithium ion. 3.6. 460. Various lithium chemistries. Very expensive. Very high energy density. Not usually available in "common ...
The ions are atoms that have lost one or more electrons (termed cations) and atoms that have gained one or more electrons ( ... H2+ is composed of two positively charged protons and one negatively charged electron, which means that the Schrödinger ... In the simplest case, the cation is a metal atom and the anion is a nonmetal atom, but these ions can be of a more complicated ... Polyatomic ions may sometimes be usefully thought of as electrically charged molecules. The term unstable molecule is used for ...
Qubit in ion-trap quantum computing[edit]. The hyperfine states of a trapped ion are commonly used for storing qubits in ion- ... consider that negatively and positively charged particles with identical mass, travelling on equivalent paths, would have the ... In atomic physics, hyperfine structure refers to small shifts and splittings in the energy levels of atoms, molecules, and ions ... However, at present no emitter is available that can be focused to address a particular ion from a sequence. Instead, a pair of ...
The size of Ln3+ ions regularly decreases with atomic number. According to Fajans' rules, decrease in size of Ln3+ ions ... In addition, electron shielding causes attraction to decrease, so remaining electrons can go farther away from the positively ... Ionic radius: the nominal radius of the ions of an element in a specific ionization state, deduced from the spacing of atomic ... In principle, the spacing between two adjacent oppositely charged ions (the length of the ionic bond between them) should equal ...
In the pH conditions of body fluid, uric acid exists largely as urate, the ion form.[1][2] The amount of urate in the body ... Various studies have found higher uric acid levels to be positively associated with consumption of meat and seafood and ...
iron ion binding. • arachidonate 5-lipoxygenase activity. • dioxygenase activity. • metal ion binding. • protein binding. • ... were positively associated with the severity of atherosclerosis, as judged by carotid intima-media thickness measurements. ...
It is believed that the connection strength between cells is caused by the number and types of ion channels embedded in the ... On-centres have a positively weighted centre and a negatively weighted surround. Off-centres are just the opposite. Positive ... resulting in the closing of Na+ cyclic nucleotide-gated ion channels (CNGs). Thus the cell is hyperpolarised. The amount of ...
... the channel opens and it allows positively charged ions (cations) to flow through the cell membrane.[2] The NMDA receptor is ... While the opening and closing of the ion channel is primarily gated by ligand binding, the current flow through the ion channel ... The N-methyl-D-aspartate receptor (also known as the NMDA receptor or NMDAR), is a glutamate receptor and ion channel found in ... which contains the positively charged insert Exon 5. The effect of this insert may be mimicked by positively charged polyamines ...
Computer-generated image of insulin hexamers highlighting the threefold symmetry, the zinc ions holding it together, and the ... The environment can be affected by biotechnologies, both positively and adversely. Vallero and others have argued that the ... Bergveld, P. (January 1970). "Development of an Ion-Sensitive Solid-State Device for Neurophysiological Measurements". IEEE ... The first BioFET was the ion-sensitive field-effect transistor (ISFET), invented by Piet Bergveld in 1970.[17][18] It is a ...
Transport of the positively charged proton is typically electrogenic, i.e. it generates an electrical field across the membrane ... Metal Ions in Life Sciences. 15. Springer. pp. 108-111. doi:10.1007/978-3-319-12415-5_4.. .mw-parser-output cite.citation{font- ... is the proton/potassium pump of the gastric mucosa which catalyzes a balanced exchange of protons and potassium ions. ...
The staining method involves application of hemalum, a complex formed from aluminium ions and hematein (an oxidation product of ... Most proteins in the cytoplasm of some cells are basic because they are positively charged due to the arginine and lysine amino ... It binds to acidophilic substances such as positively charged amino-acid side chains (e.g. lysine, arginine). ...
... positively charged ions), which are accelerated again as they leave the terminal. The two main types of electrostatic ... The Relativistic Heavy Ion Collider, and Large Hadron Collider also make use of superconducting magnets and RF cavity ... Of these, only about 1% are research machines with energies above 1 GeV, while about 44% are for radiotherapy, 41% for ion ... This is possible with the acceleration of atomic nuclei by using anions (negatively charged ions), and then passing the beam ...
Carbon ions. *Carbides [:C≡C:]2-, [::C::]4-, [:C=C=C:]4- ... and is also slightly positively charged compared to carbon ... "Theoretical Analysis of the Bonding between CO and Positively Charged Atoms". J. Phys. Chem. A. 101 (49): 9551-9559. doi: ...
Schematic diagram of a micelle - the lipophilic tails of the surfactant ions remain inside the oil because they interact more ... pH-dependent primary, secondary, or tertiary amines; primary and secondary amines become positively charged at pH , 10:[27] ...
Chemist positively charged with economic espionage after stealing paint formula from employer. FBI had an ion him the whole ... An ion walks into a bar and says, "Hey, bartender. Can you help me? I seem to be missing an electron.". The bartender says, " ... Skalagrim: An ion walks into a bar and says, "Hey, bartender. Can you help me? I seem to be missing an electron.". The ... The ion replies, "Im positive!". /Just getting it out of the way.. ...
... ... "Investigating the dynamics of ion-surface interactions using electron-spin-polarized positively charged helium ions." (2002) ... Spin-polarized He+ ions are produced in a radio-frequency driven discharge and directed at selected surfaces. Emitted electrons ... A powerful technique for studying surface states and interactions has been Ion Neutralization Spectroscopy, in which noble gas ...
Assembly of Positively Charged Porphyrins Driven by Metal Ions: A Novel Polymeric Arrangement of Cationic Metalloporphyrin ...
... thus when they form ions, metals give up electrons (forming cations) and nonmetals take up electrons (forming anions). ... What are ions and ionic bonds?. Ions are formed when atoms gain or lose electrons. Positively charged cations are formed when ... It becomes an ion . Atoms that lose electrons ( metals ) become positively charged and are called Cations . Atoms that gain ... Cations are most often metals, as cations are positively charged ions meaning they have lostelectron(s). As a general rule, ...
What is An Ion- Examples - Cation s and Anions -[Positively And Negatively] Charged Ion ... "What is An Ion- Examples - Cation s and Anions -[Positively And Negatively] Charged Ion" - Education Enlightenment frameborder ... Continue reading What is An Ion- Examples - Cation s and Anions -[Positively And Negatively] Charged Ion ... Positively And Negatively] Charged Ion,/a,,/blockquote, ,script type=text/javascript, ,!--//--,,![CDATA[//,,!-- !function(a,b ...
Depending on the charge of the ion, two different classes can be distinguished: Cation (positively charged). When hydrogen ... Hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes.[1] ... In addition, the ions produced by the reaction of these cations with water as well as their hydrates are called hydrogen ions: ... In connection with acids, hydrogen ions typically refer to hydrons. Anion (negatively charged). Hydrogen anions are formed when ...
Positively charged membrane. US20060261010 *. Feb 9, 2004. Nov 23, 2006. Drake Ronald N. Continuous selective ion exchange ... Ion exchange process with magnetic ion exchange resins. US2837496 *. Dec 31, 1952. Jun 3, 1958. Hercules Powder Co Ltd. Graft ... The separated and washed product acted as a weak base ion-exchange resin and as such had an ion-exchange capacity of 2.6 ... The magnetic weak acid resin so obtained had an ion-exchange capacity of 4.3 milliequivalents per gram. It was useful as an ion ...
This makes the chlorine atom a nega…tively charged ion and the sodium atom a positively charged ion. The bond between them is ... An ionic compound contains at least one positive ion and at least one negative ion, bonded together by this magnetic ... producing oppositely charged ions. These ions are then attracted to one another. These bonds usu…ally form between a metal and ... On the other hand, ionic silver is a solution consisting of water and single atom silver ions, as opposed to clusters of single ...
mobility of positively and negatively charged ions, N. {\displaystyle N}. : ion concentration, α. {\displaystyle \alpha }. : ... module of the ion charge, b. +. {\displaystyle b^{+}}. and b. −. {\displaystyle b^{-}}. : ... Small holes in cell membranes, called ion channels, are selective to specific ions and determine the membrane resistance. ... which is determined by the ratio of the concentration of ions N. {\displaystyle N}. to the concentration of molecules of the ...
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, ...
Ion Ion, any atom or group of atoms that bears one or more positive or negative electrical charges. Positively charged ions are ... An ion pair, for the physicist, is the positively charged particle (positive ion) and the negatively charged particle (negative ... Ions are formed by the addition of electrons to, or the removal of electrons from, neutral atoms or molecules or other ions ... Ion pair Ion pair, in physics and chemistry, a duplex of charged particles (ordinarily charged atoms or molecules), one ...
Jayes, F. C.L. ; Day, R. N. ; Garmey, J. C. ; Urban, R. J. ; Zhang, G. ; Veldhuis, J. D. / Calcium ions positively modulate ... Jayes, F. C. L., Day, R. N., Garmey, J. C., Urban, R. J., Zhang, G., & Veldhuis, J. D. (2000). Calcium ions positively modulate ... Jayes, FCL, Day, RN, Garmey, JC, Urban, RJ, Zhang, G & Veldhuis, JD 2000, Calcium ions positively modulate follicle- ... T1 - Calcium ions positively modulate follicle-stimulating hormone- and exogenous cyclic 3′,5′-adenosine monophosphate-driven ...
charged ions or negatively charged ions while excluding passage of ions of the ... material produces a semi-permeable barrier that allows passage of either positively. ... carbon, ion exchange, ozone, enhanced coagulation.. Biological solids Pretreatment using disinfection (i.e. chlorination),. ... relatively small organic compound and (multivalent) ions from a solvent. Nanofiltration. systems typically operate at lower ...
IONIC BONDS occur between positively- and negatively-charged ions.. *Water is essential to life. Cells are largely composed of ... Water molecules tend to IONIZE, or dissociate, into a hydrogen ion, H+, and a hydroxide (hydroxyl) ion, OH_. *An ACID is any ... IONS are atoms or molecules with a positive or negative charge due to a deficit or excess of electrons. *Electrons are ... A COMPOUND consists of two or more different kind of atoms or ions in definite proportions. *ATOMS are the smallest particles ...
... hydrogen ion translation, English dictionary definition of hydrogen ion. n. The positively charged ion of hydrogen, H+, formed ... by removal of the electron from atomic hydrogen and found in the form of hydronium ion in all aqueous... ... Define hydrogen ion. hydrogen ion synonyms, hydrogen ion pronunciation, ... Related to hydrogen ion: hydrogen ion concentration. hydrogen ion. n.. The positively charged ion of hydrogen, H+, formed by ...
... negative ion), which is created by an electron gain and is attracted to the anode. The valence of an ion is equal to the number ... positive ion), which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion ( ... Ion definition, an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation ... Ions can be either positively or negatively charged.. Show More. The New Dictionary of Cultural Literacy, Third Edition ...
Ion thrusters emit a beam of positively charged xenon ions. To keep the spacecraft from accumulating a charge, another cathode ... Electrostatic ion thrusters[edit]. Gridded electrostatic ion thrusters[edit]. Main article: Gridded ion thruster ... Electromagnetic ion thrusters use the Lorentz force to move the ions.. Power supplies for ion thrusters are usually electric ... "Ion Propulsion".. *^ a b Szondy, David. "NASAs NEXT ion thruster runs five and a half years nonstop to set new record". ...
cation A positively charged ion; opposite is anion.. caulogenesis Stem organogenesis; induction of shoot development from ... co-factor An organic molecule or inorganic ion necessary for the normal catalytic activity of an enzyme. ...
... called ions, that are found within cells, between cells, in the bloodstream, and in other fluids throughout the body. ... Electrolyte Tests Definition Electrolytes are positively and negatively charged molecules, ... Electrolytes are positively and negatively charged ions that are found within the cells and extracellular fluids, including ... Electrolytes are positively and negatively charged molecules, called ions, that are found within cells, between cells, in the ...
A calcium ion is shown in green. ... A positively selected FBN1 missense variant reduces height in ... Asgari, S., Luo, Y., Akbari, A. et al. A positively selected FBN1 missense variant reduces height in Peruvian individuals. ...
to be due to the movement of positively charged colloidal particles which. ... ions. Also following ionization with some substances as lithium, the ions. may be detected in the urine, although they are not ... as the ions, and the current can be used to introduce ions into the tissues, the ... tissues, zinc ions enter the tissues, zinc ions enter the tissues and producing ...
Ions are either negatively or positively charged. A cation is a positively charged ion and an anion is a negatively charged ion ... Regardless of how many protons an element has, it becomes an ion when one or more valence electrons is stripped from the atom. ...
A bond that results from electrostatic attraction between oppositely charged ions. The cation is positively charged, while the ... Ion A charged species created by the gain or loss of an electron from an atom or neutral molecule. ... A mathematical formula whose consequence is that negatively and positively charged particles attract each other and similarly ...
Cations are positively charged ions.. Theyre formed by losing electrons.. And this is what throws some students off. ... So an ion is always formed by electrons, these that are being lost or gained. ... If you lose electrons or gain electrons to an atom, you will create an ion. ... So, we are not adding, we are losing those negatively charged ions, ...
positively charged ions. ANIONS. Negatively charged ions. FILTRATION. Hydrostatic pressure in capillaries , hydrostatic ...
Ion. an atom or molecule that carries a charge. Cation. positively charged ions. ... hydroxide ion. OH-. Acids. substances that gives up protons during chemical reactions and raise the hydrogen ion concentration ... molecules that acquire protons during chemical reactions and that lower the hydrogen ion concentration of water. ...
When an atom interacts with a physical force like heat or electricity, it becomes an ion. Ions have positive or negative ... Anomia, the game where common knowledge becomes uncommonly fun! Our minds are positively brimming with random information. ...
The ion conductive membrane also selectively conducts positively charged ions. Electrically, the anode conducts electrons to a ... The ion conductive membrane separates the hydrogen and oxygen gas distribution layers. In chemical terms, the anode comprises ... Solid oxide fuel cells employ a hard, non-porous ceramic compound for ion exchange and may be suitable for use with the present ... The ion conductive membrane blocks the electrons, and electrically isolates the chemical anode (hydrogen gas distribution layer ...
The atom becomes a positively charged ion. It will be positively charged because the number of protons is now greater than the ... Protons are positively charged, while electrons are negatively charged. Usually an atom has the same number of electrons as ... If there is a plus next to the elements symbol, it indicates it is positively charged. With a minus symbol, it is negatively ... If there is no plus or minus symbol, and your chemistry problem does not consider ions, the protons and electrons are likely ...
Exchangeable bases are positively charged ions. *The amounts listed for minerals in the non-GMO corn are absurd. Here are ...
  • 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. (
  • The cation is positively charged, while the anion is negatively charged. (
  • A cation is a positively charged ion and an anion is a negatively charged ion. (
  • A "cation" is a positively charged ion. (
  • Therefore ion exchange chromatography consists of cation exchange chromatography and anion exchange chromatography. (
  • In cation exchange chromatography the Na+ ion will compete with the bound protein for the negative functional group, and in anion exchange chromatography, the Cl- ion will compete to bind the columns. (
  • bicarbonate A salt containing a cation (any positively-charged ion) and the radical HCO 3 , e.g. (
  • 3. The system of claim 2 wherein the internal reservoir of eluant ions comprises cation exchange resin. (
  • Cation exchange and anion exchange are, respectively, the exhange of positively and negatively charged ions. (
  • Nonmetals generally are more electronegative than metals, meaning that they have a stronger pull on their electrons - thus when they form ions, metals give up electrons (forming cations) and nonmetals take up electrons (forming anions). (
  • How ions form cations and anions? (
  • are called ions - cations and anions. (
  • Atoms of Metals lose electrons to empty their outer shell and become positive ions or cations.Atoms of non-metals gain electrons to fill their outer shell and become negative ions or anions. (
  • Gaining or losing electrons atoms become ions (anions or cations). (
  • Cations are most often metals, as cations are positively charged ions meaning they have lostelectron(s). (
  • Positively charged ions ( cations ) move toward the cathode, while negatively charged ions (anions) move toward the anode. (
  • Positive ions are called cations . (
  • All simple metal ions are cations. (
  • Some are positively charged and are known as cations. (
  • Positively charged cations and negatively charged anions attract one another. (
  • Clay particles are negatively charged and attract positively charged ions (cations). (
  • Many organic molecules exist that can bind positively charged ions, or cations, and this has much to do with the fact that it is easy to synthesize organic molecules with negatively charged parts. (
  • It is those negatively charged parts that interact with positive ions, or cations, grabbing them out of solution and holding onto them so the cations cannot react or interfere with other processes. (
  • The addition of the calcium ions created positively-charged oxygen vacancies. (
  • Spin-labeling techniques, specifically using electron-spin-polarized 4He+ ions coupled with energy-resolved measurements of the polarization of ejected electrons, are providing significant insight into surface electronic states and the dynamics of the neutralization of charged particles at clean and adsorbate-covered metal surfaces. (
  • Many crystalline substances are composed of ions held in regular geometric patterns by the attraction of the oppositely charged particles for each other. (
  • A mathematical formula whose consequence is that negatively and positively charged particles attract each other and similarly charged species repel each other. (
  • A year later, Willy Wien began working with 'positive rays' -- the stream of positively charged particles that emanate from the anode and move toward the cathode. (
  • Because increased sodium in the tubules increases hydrogen ion loss at the same time as potassium, diuretics may also induce a hypokalaemic metabolic alkalosis. (
  • That molecule, a salt of cyanoform, has the same structure as the acid except it has lost the positive hydrogen ion , resulting in a negative molecule that is paired with a positive sodium ion. (
  • Like potassium, sodium ions are positively charged. (
  • Cartilage also contains negatively charged proteins and positively charged sodium ions. (
  • They have demonstrated what happens during the opening or closure of an ion channel with a diameter corresponding to that of a single sodium or chloride ion. (
  • For example the contents of positive sodium and potassium ions and negatively charged chloride ions are quite different. (
  • By rapidly opening channels for sodium ions the membrane potential is altered radically within a thousandth of a second. (
  • Thus there is a high concentration of sodium ions present outside the neuron, and a high concentration of potassium ions inside. (
  • Thus sodium channels allow sodium ions through the membrane while potassium channels allow potassium ions through. (
  • Now, under resting conditions, the potassium channel is more permeable to potassium ions than the sodium channel is to sodium ions. (
  • So there is a slow outward leak of potassium ions that is larger than the inward leak of sodium ions. (
  • Similarly, there is a pressure for the sodium ions to enter the neuron, but they are prevented from doing so by the membrane and the pumping mechanisms that remove any ions that manage to get in. (
  • However, if the sodium channels are opened, positively charged sodium ions flood into the neuron, and making the inside of the cell momentarily positively charged - the cell is said to be depolarized. (
  • Thus, there is first an influx of sodium ions (leading to massive depolarization) followed by a rapid efflux of potassium ions from the neuron (leading to repolarisation). (
  • Increasing the size of the axon retains more of the sodium ions that form the internal depolarisation wave inside the axon. (
  • If you look at the diagram carefully, you will see that the sodium ions and chloride ions alternate with each other in each of the three dimensions. (
  • So, too, are the sodium ions produced in the softener's brine tank. (
  • The magnesium and calcium enter the ion exchange unit and stick to negatively charged beads where they replace the weaker charge of the sodium. (
  • Soft water then enters the house with a concentration of sodium ions instead of magnesium and calcium. (
  • Ions that the deionisation process removes include calcium, chlorides, and sodium. (
  • This results in the atomic radius decreasing.Anions on the other hand are most often nonmetals, as anions are negatively charged ions meaning they have gained electron(s). (
  • negatively charged ions, anions . (
  • negative ions, or anions, are formed by the gain of electrons. (
  • Negative ions are called anions . (
  • Positively charged ions, called anions, are exchanged for hydrogen and hydroxyl. (
  • IONS are atoms or molecules with a positive or negative charge due to a deficit or excess of electrons. (
  • Water has been called the universal SOLVENT, a substance that can dissolve SOLUTES including polar molecules and ions. (
  • Ion thrusters use beams of ions (electrically charged atoms or molecules) to create thrust in accordance with momentum conservation . (
  • That which holds together atoms in molecules and ions in lattices. (
  • A regularly repeating three-dimensional array of atoms, molecules, or ions. (
  • When water molecules align with each other, a weak bond is established between the negatively charged oxygen atom of one water molecule and the positively charged hydrogen atoms of a neighboring water molecule. (
  • These channels consist of single molecules or complexes of molecules and have the ability to allow passage of charged atoms, that is ions. (
  • The ion channels consist of single molecules or complexes of molecules, that forms the wall of the channel - or pore - that traverses the cell membrane and connects the exterior to the interior of the cell (Figure 1B and 1D). (
  • The compounds consist of mecury ions (Hg 2+ ), each linked to two propiolactam molecules, one on either side. (
  • the propiolactams, small organic molecules, connect to other metal ions, such as erbium (Er 3+ ), to form large rings. (
  • Many organic molecules exist that can bind positively charged ions or. (
  • The synthesis is extremely modular, as well, so we imagine these molecules can be easily modified to bind a wide variety of negative ions with great specificity. (
  • Attempts at manufacturing organic binding agents with positively charged parts is not hard, but designing them in such a way that they don't attract the attention of solvent molecules has been a major challenge for chemists. (
  • adsorption The chemical adhesion of atoms, ions, or molecules of one substance (either a gas, liquid, or dissolved solid) to the surface of another substance, resulting in a film of the first substance being weakly bonded to the interface between the two substances. (
  • amount of substance The number of discrete particles (such as molecules, atoms, ions, electrons, or any other atomic-scale entity) in a given sample of matter, divided by the Avogadro constant. (
  • Anion-Exchange chromatography involves the use of positively charged beads. (
  • Anion-exchange chromatography mainly recollects biomolecules by the interaction of amine groups on the ion-exchange resin with aspartic or glutamic acid sidechains, which have pK of ~ 4.4. (
  • The gas ionizes and turns into plasma, a mixture of electrons and positively charged ions. (
  • Name and write the formulas for common transition metal ions. (
  • For example, in a wire, the metal ions do not move, but the electrons move as electricity. (
  • 3.  This definition includes the hydrogen atom and most of the transition metal ions. (
  • Ions can be either positively or negatively charged. (
  • Free radicals may be electrically neutral or either positively or negatively charged. (
  • These changes disrupt the flow of potassium ions in the inner ear and in cardiac muscle, leading to hearing loss and an irregular heart rhythm characteristic of Jervell and Lange-Nielsen syndrome. (
  • Potassium ions are positively charged in the body. (
  • In addition, they pump in positively charged potassium ions (potash to the gardeners out there! (
  • This has the effect of opening the potassium channels, allowing potassium ions to leave the cell. (
  • the other, called the anode , becomes positively charged. (
  • The invention is also directed to lithium ion batteries in which the nanoporous framework material is incorporated in an anode of the battery. (
  • Heterogeneous metal hydride (MH) compositions comprising a main region comprising a first metal hydride and a secondary region comprising one or more additional components selected from the group consisting of second metal hydrides, metals, metal alloys and further metal compounds are suitable as anode materials for lithium ion cells. (
  • The capillary system consists of a pin electrode for the negatively charged cathode side of the current supplying device, and a plate electrode for the positively charged anode. (
  • The acid is produced when the copper dissolves from the anode, giving high local concentration of copper ions (Cu 2+ ). (
  • Metallic elements produce positively charged ions by losing electr. (
  • Do metals form positive or negative ions? (
  • Ion , any atom or group of atoms that bears one or more positive or negative electrical charges. (
  • Electromagnetic thrusters on the contrary use the Lorentz force to accelerate all species (free electrons as well as positive and negative ions) in the same direction whatever their electric charge , and are specifically referred as plasma propulsion engines , where the electric field is not in the direction of the acceleration. (
  • Ions have positive or negative charges and are always looking to become neutral again. (
  • IonX is a patented process that builds negative ions into the structure of the fabric. (
  • What possible difference could negative ions make? (
  • If you do a quick study on positive and negative ions , you'll discover that our air is bombarded with positive ions from things like pollution, computers, TVs and fluorescent lights. (
  • Negative ions, on the other hand, are found in nature - at the beach, near a waterfall, in the mountains, and after a storm. (
  • Negative ions tend to give us a sense of well-being, alleviate depression, reduce stress and increase energy. (
  • The positive effects of negative ions have been studied for many years. (
  • Positively charged germs are neutralized by negative ions. (
  • Ionic bonds hold atoms together using the electrostatic charge between their positive and negative ions. (
  • How are positive and negative ions formed? (
  • Positive and negative ions are formed by gaining or losing electrons from neutral atoms. (
  • A positive ion and a negative ion will move together. (
  • This means that the membrane has a charge on the inside face that is negative relative to the outside, as more positively charged ions flow out of the neuron than flow in. (
  • But Melrose and his colleagues have shown that it is negative ions in the solution that appear to regulate the growth. (
  • These ions travel through the body and attach themselves to toxic substances, thereby neutralizing these toxins negative charges. (
  • Electrolytes are positively and negatively charged ions that are found within the cells and extracellular fluids, including blood plasma. (
  • contain ions and so are electrolytes. (
  • These channels transport positively charged potassium atoms (ions) out of cells. (
  • Calcium channels transport positively charged calcium atoms (calcium ions) into cells. (
  • If the atom loses or gains electrons, it is an electrically charged ion. (
  • This electrically charged atom is referred to as an ion. (
  • An ion is an electrically charged atom or group of atoms. (
  • However, scientists at the Stuttgart-based Max Planck Institute for Solid State Research have now come up with a surprise: in a special perovskite, another material used for solar cells, light not only releases electrons, but also electrically charged atoms, known as ions. (
  • The positively charged ion of hydrogen, H + , formed by removal of the electron from atomic hydrogen and found in the form of hydronium ion in all aqueous solutions of acids. (
  • Heating the atom breaks it into two parts: (1) a positively charged hydrogen ion, H+ (2) a negatively charged electron. (
  • The resulting gaps in the crystal lattice allow ion conduction in much the same way as electron holes allow electron conduction. (
  • It is presumed the nitrogens withdraw electron density from the carbon and hydrogen atoms closest to the molecule's hole, thereby creating an alluring binding spot for fluorine or chlorine ions. (
  • On the other hand, ionic silver is a solution consisting of water and single atom silver ions , as opposed to clusters of single atoms. (
  • A particulate silver solution generally contains up to 90% or more silver particles, while an ionic silver solution generally contains up to 90% or more silver ions. (
  • the reason for de-ionized water is that it can't carry a charge and then we are more likely to have positively charged silver ions and not other varieties of silver particles. (
  • Ionic in size, positively charged silver ions. (
  • This allows positively charged proteins , for example, to bind to the negatively charged beads on the column and the negatively charged proteins to flow through the column. (
  • What is the force that holds different atoms or ions together? (
  • A COMPOUND consists of two or more different kind of atoms or ions in definite proportions. (
  • a substance composed of atoms or ions of two or more elements that are chemically combined. (
  • The calcium and magnesium ions in hard water are positively charged. (
  • In labs, EDTA (ethylenediaminetetraacetic acid) is frequently used to remove calcium and magnesium ions so that chemical reactions go faster or more efficiently. (
  • Does the sign of the emf depend on whether the mobile ions in the blood are predominantly positively or negatively charged? (
  • For the chemist, however, the phenomenon as such is most exciting primarily because it creates the fundamental possibility of releasing mobile ions with the help of light, namely those charge carriers which transport electricity in electrochemical applications such as batteries, fuel cells or electrochemical sensors and switches. (
  • Hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes . (
  • During the dawn of Big Bang, when the temperature of the young universe had cooled down, the first molecular bond of HeH+ was created through the association of the H+ ( hydrogen ion or proton) and helium atoms due to radiation, scientists proposed. (
  • Because these ions are capable of combining with and neutralizing excess hydrogen ions (H+) upon addition of acid to a body of water, they can help maintain a relatively constant hydrogen ion concentration, and therefore a consistent pH. (
  • Finally, 43 AdegC temperature, 500 rpm stirring rate, 1000 mg Radix Paeoniae Alba, 2.0 mol*L-1 hydrogen ion concentration, 0.084 g MnSO4, 0.835 g KBrO3, 1mL acetone and 100 mL total volume were chosen as the optimal experimental conditions. (
  • The term RTA is applied to a group of defects in bicarbonate reabsorption, hydrogen ion excretion, or both. (
  • The physiologic importance of limiting the change in hydrogen ion concentration within the body fluid compartments is well recognized. (
  • The colour of the juice changes in response to changes in its hydrogen ion concentration. (
  • The pH of seawater has decreased by 0.1 since the beginning of the industrial era, corresponding to a 26 per cent increase in hydrogen ion concentration. (
  • acid A compound which, when dissolved in water, gives a pH of less than 7.0, or donates a hydrogen ion. (
  • So called because ions move toward the electrode of opposite charge. (
  • Each electrode attracts ions of opposite charge . (
  • The amount (in "Faraday" units) of electric charge required to discharge one mole of substance at an electrode is equal to the number of "excess" elementary charges on that ion. (
  • 12. Fluoride ion selective electrode (ISE), NaF combination or with calomel-type reference electrode. (
  • 13. pH/ion meter with millivolt readout and pH electrode. (
  • If there is no plus or minus symbol, and your chemistry problem does not consider ions, the protons and electrons are likely equal. (
  • An ion has unequal numbers of protons and electrons. (
  • An ionic bond is a bond formed by the attraction between two oppositely charged ions. (
  • A bond that results from electrostatic attraction between oppositely charged ions. (
  • The term refers strictly to gridded electrostatic ion thrusters , and is often incorrectly loosely applied to all electric propulsion systems including electromagnetic plasma thrusters . (
  • Temporarily stored electrons are finally reinjected by a neutralizer in the cloud of ions after it has passed through the electrostatic grid, so the gas becomes neutral again and can freely disperse in space without any further electrical interaction with the thruster. (
  • It was similar to a gridded electrostatic ion thruster and used mercury for propellant. (
  • Protein binds to ion exchangers by electrostatic forces between the surface of the protein charges and cluster of the charged group on the exchangers. (
  • Units that use media like activated charcoal, or electrostatic means to "condition" water, are the most common alternatives to ion-exchange softeners that use salt. (
  • The ion replies, "I'm positive! (
  • An ion thruster ionizes a neutral gas by extracting some electrons out of atoms , creating a cloud of positive ions. (
  • Positive ions can make us feel tired, irritable and depressed. (
  • A summary of the ion-exchange chromatography include: If a proton has a net positive charge at pH of 7 then it will bind to a column of beads that contain the carboxyl groups, where as a negatively charged proteins will not. (
  • An atom that is ionized makes two ions, one positive, and one negatively charged. (
  • These sheets are then lowered into a solution such as copper, the ions from the copper solution get attracted to the positive sheet of metal and forms 99.999% pure copper. (
  • Making an ion from an atom or molecule is called ionization . (
  • Polarity simply means that the molecule has both a positively and negatively charged end. (
  • Several ion channels are regulated by a receptor localized to one part of the channel molecule which upon activation alters its shape. (
  • An immediate change in the shape of the molecule leads to either an opening or a closure of the ion channel. (
  • Indiana University Bloomington chemists have designed an organic molecule that binds negatively charged ions, a feat they hope will lead to the development of a whole new molecular toolbox for biologists, chemists and medical researchers who want to remove chlorine, fluorine and other negatively charged ions from their solutions. (
  • Ion Exchange Chromatography (IEC) is a purification method aimed at separating proteins based on charge, which is dependent on the composition of the mobile phase (a separation of mixtures that is dissolved). (
  • In particular, the columns of the present invention can be used as the separation column in electroelution chromatography and are also adaptable for use as a self-regenerating suppressor in suppressed ion chromatography. (
  • Single Column Ion Chromatography (SCIC) is a method of ion analysis in which ions are separated in an ion exchange column (e.g., separator column) and subsequently measured by a conductivity detector connected directly to the separator column. (
  • Method 7906 (Fluorides by IC) employs the same sampling procedure, but uses ion chromatography for measurement. (
  • Media for membrane ion exchange chromatography based on polymeric primary amines, sorption device containing that media, and chromatography scheme and purification method using the same. (
  • When current flows, positively charged copper ions move towards the cathode and deposit themselves there, building outwards. (
  • that allows negatively charged chlorine atoms (chloride ions) to cross the cell membrane. (
  • An ion thruster or ion drive is a form of electric propulsion used for spacecraft propulsion . (
  • What kind of ions do metals form? (
  • These three nutrients exist in the soil solution in the form of ions. (
  • As a result, ions from the compound become available in the liquid form, which is called the electrolyte . (
  • Elements in the main groups in the Periodic Table form colourless ions. (
  • The transition metals usually form coloured ions. (
  • Ionic compounds dissolve in water to form ions. (
  • The atoms readily lose the outermost electrons and form positively charged ions. (
  • The neuronal membrane also contains specialised proteins called channels , which form pores in the membrane that are selectively permeable to particular ions. (
  • 3. Would neon normally form ions? (
  • Transition elements can form ions with several different charges so these must be looked up on a chart (see Table 1 at the end of the handout). (
  • Deionised water is a highly purified form of water in which all ions have been removed through a process called "ion exchange. (
  • To be completely correct - the Swedish chemists did not actually find pure metallic lithium, but lithium ions in the form of a salt. (
  • Ion conductivity increased by a factor of one hundred. (
  • A previously unknown photoeffect: in some materials, such as in the perovskite methylammonium lead iodide (MAPI), ions contribute very strongly to light-induced conductivity. (
  • In their experiments, the researchers now observed that ions, that is charged atoms, contribute to conductivity to an unexpectedly high degree when the material is illuminated. (
  • They added ions to tantalum disulphide and studied how its conductivity was affected. (
  • 3]. Hydroxide ion greater than 1/10 of the fluoride level will interfere positively. (
  • Polyatomic ions usually consist of all non-metal atoms. (
  • Regardless of how many protons an element has, it becomes an ion when one or more valence electrons is stripped from the atom. (
  • When an atom interacts with a physical force like heat or electricity, it becomes an ion. (
  • But sometimes the polyatomic ion can have a metallic atom too. (
  • Exploring new materials for better lithium-ion batteries. (
  • As employee number seven at Tesla, Gene -Berdichevsky was instrumental in solving one of its earliest challenges: the thousands of lithium--ion batteries the company planned to pack into its electric sports car caught fire far more often than manufacturers claimed. (
  • Now Berdichevsky has cofounded Sila Nanotechnologies, which aims to make better lithium-ion batteries. (
  • Silicon has almost 10 times the theoretical capacity of the material most often used in lithium-ion batteries, but it tends to swell during charging, causing damage. (
  • Lithium-ion batteries have brought the greatest benefit to humankind, as they have enabled the development of laptop computers, mobile phones, electric vehicles and the storage of energy generated by solar and wind power. (
  • Neurons, like all cells, maintain different concentrations of certain ions (charged atoms) across their cell membranes. (
  • The process involves pumping positively charged hydrogen ions, called protons, across a membrane. (
  • This phenomenon is generated through the flow of positively charged ions across the neuronal membrane. (
  • That light influences ion transport has only previously been demonstrated in biology: Illumination is able to indirectly alter the permeability of a cell membrane. (
  • IONIC BONDS occur between positively- and negatively-charged ions. (
  • The bonds holding these ions together are called 'ionic' bonds. (
  • Excess ions are subsequently pumped in/out of the neuron. (
  • The key component was positively charged copper ions at the catalyst surface. (
  • Most water deionizers are filled with a resin that bonds with all other types of ions and removes them from the water, leaving only the hydrogen and hydroxyl ions behind. (
  • The method of accelerating the ions varies, but all designs take advantage of the charge / mass ratio of the ions. (
  • According to, a typical atom has no electrical charge because the number of positively charged protons is the same as the number of negatively charged electrons. (
  • in other words, the net charge on the protein will be the same sign as that of the counterions displaced-therefore "ion exchange. (
  • The charge on a proton is measured as +1 (positively charged). (
  • Two ions of the same charge will move apart. (
  • Most ions have a charge of less than 4, but some can have higher charges. (
  • Reciprocal and reversible transfer of ions of the same charge between a solution and a relatively insoluble solid in contact with it. (
  • Write the chemical shorthand (chemical symbol with the charge as a superscript) for the most common ions of the following elements. (
  • The charge on an ion refers to the number of electrons lost or gained. (
  • Note that the Roman numeral following the metal name is the same as the charge of the ion. (
  • In connection with acids, hydrogen ions typically refer to hydrons . (
  • [1] They are attracted to anodes (positively charged electrodes). (
  • ammonium The chemical ion (NH 4 +) derived from ammonia that does not appear in a free state, but forms salts and compounds analogous to those of the alkali metals. (