Protons: 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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Proton Pumps: Integral membrane proteins that transport protons across a membrane. This transport can be linked to the hydrolysis of ADENOSINE TRIPHOSPHATE. What is referred to as proton pump inhibitors frequently is about POTASSIUM HYDROGEN ATPASE.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Membrane Lipids: Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.Membrane Potentials: 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).Intracellular Membranes: Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.Cell Membrane Permeability: A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.Membranes, Artificial: 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.Erythrocyte Membrane: The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.Membrane Fluidity: The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.Hydrogen-Ion Concentration: 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)Proton Pump Inhibitors: Compounds that inhibit H(+)-K(+)-EXCHANGING ATPASE. They are used as ANTI-ULCER AGENTS and sometimes in place of HISTAMINE H2 ANTAGONISTS for GASTROESOPHAGEAL REFLUX.Basement Membrane: A darkly stained mat-like EXTRACELLULAR MATRIX (ECM) that separates cell layers, such as EPITHELIUM from ENDOTHELIUM or a layer of CONNECTIVE TISSUE. The ECM layer that supports an overlying EPITHELIUM or ENDOTHELIUM is called basal lamina. Basement membrane (BM) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. BM, composed mainly of TYPE IV COLLAGEN; glycoprotein LAMININ; and PROTEOGLYCAN, provides barriers as well as channels between interacting cell layers.Magnetic Resonance Spectroscopy: 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).Lipid Bilayers: Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.Membrane Transport Proteins: Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Models, Biological: 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.Kinetics: The rate dynamics in chemical or physical systems.Liposomes: Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.Protein Binding: 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.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Molecular Sequence Data: 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.Calcium: 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.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Escherichia coli: 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.Amino Acid Sequence: 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.Mitochondrial Membranes: The two lipoprotein layers in the MITOCHONDRION. The outer membrane encloses the entire mitochondrion and contains channels with TRANSPORT PROTEINS to move molecules and ions in and out of the organelle. The inner membrane folds into cristae and contains many ENZYMES important to cell METABOLISM and energy production (MITOCHONDRIAL ATP SYNTHASE).Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Biological Transport, Active: The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.Protein Structure, Tertiary: 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.Potassium: 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.Cells, Cultured: 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.Protein Conformation: 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).Mutation: 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.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Bacterial Proteins: Proteins found in any species of bacterium.Water: 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)Ion Channels: 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.Synaptic Membranes: Cell membranes associated with synapses. Both presynaptic and postsynaptic membranes are included along with their integral or tightly associated specializations for the release or reception of transmitters.Temperature: 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.Proton-Motive Force: Energy that is generated by the transfer of protons or electrons across an energy-transducing membrane and that can be used for chemical, osmotic, or mechanical work. Proton-motive force can be generated by a variety of phenomena including the operation of an electron transport chain, illumination of a PURPLE MEMBRANE, and the hydrolysis of ATP by a proton ATPase. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed, p171)Proton-Translocating ATPases: Multisubunit enzymes that reversibly synthesize ADENOSINE TRIPHOSPHATE. They are coupled to the transport of protons across a membrane.Microscopy, Fluorescence: Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.Phosphatidylcholines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.Detergents: Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.Adenosine Triphosphate: 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.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Bacteriorhodopsins: Rhodopsins found in the PURPLE MEMBRANE of halophilic archaea such as HALOBACTERIUM HALOBIUM. Bacteriorhodopsins function as an energy transducers, converting light energy into electrochemical energy via PROTON PUMPS.Cell Membrane Structures: Structures which are part of the CELL MEMBRANE or have cell membrane as a major part of their structure.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cattle: 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.Freeze Fracturing: Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.Molecular Weight: The sum of the weight of all the atoms in a molecule.Microscopy, Confocal: A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.Cytoplasm: The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)Diffusion: 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.Rabbits: 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.Electric Conductivity: The ability of a substrate to allow the passage of ELECTRONS.Fluorescent Dyes: 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.Valinomycin: A cyclododecadepsipeptide ionophore antibiotic produced by Streptomyces fulvissimus and related to the enniatins. It is composed of 3 moles each of L-valine, D-alpha-hydroxyisovaleric acid, D-valine, and L-lactic acid linked alternately to form a 36-membered ring. (From Merck Index, 11th ed) Valinomycin is a potassium selective ionophore and is commonly used as a tool in biochemical studies.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Purple Membrane: Functionally and structurally differentiated, purple-pigmented regions of the cytoplasmic membrane of some strains of Halobacterium halobium. The membrane develops under anaerobic conditions and is made almost entirely of the purple pigment BACTERIORHODOPSINS. (From Singleton & Sainsbury Dictionary of Microbiology and Molecular Biology, 2d ed)Endoplasmic Reticulum: A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)Mitochondria: Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)Endocytosis: Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.Golgi Apparatus: A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Vacuolar Proton-Translocating ATPases: Proton-translocating ATPases that are involved in acidification of a variety of intracellular compartments.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Protein Structure, Secondary: 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.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Microvilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Subcellular Fractions: Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)Peptides: 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.Extraembryonic Membranes: The thin layers of tissue that surround the developing embryo. There are four extra-embryonic membranes commonly found in VERTEBRATES, such as REPTILES; BIRDS; and MAMMALS. They are the YOLK SAC, the ALLANTOIS, the AMNION, and the CHORION. These membranes provide protection and means to transport nutrients and wastes.Vacuoles: Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.Permeability: Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Oxidation-Reduction: 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).Aspartic Acid: One of the non-essential amino acids commonly occurring in the L-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter.Cholesterol: The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.Ion Transport: 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.Thermodynamics: 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)Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Electron Transport Complex IV: A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Electron Transport: The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Structure-Activity Relationship: 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.Microscopy, Immunoelectron: Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Mathematics: The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Phosphatidylethanolamines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to an ethanolamine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and ethanolamine and 2 moles of fatty acids.Biological Transport: 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.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Dicyclohexylcarbodiimide: A carbodiimide that is used as a chemical intermediate and coupling agent in peptide synthesis. (From Hawley's Condensed Chemical Dictionary, 12th ed)Hydrogen: 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.Octoxynol: Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.Electrophysiology: 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.Phosphatidylserines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a serine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and serine and 2 moles of fatty acids.Membrane Potential, Mitochondrial: The voltage difference, normally maintained at approximately -180mV, across the INNER MITOCHONDRIAL MEMBRANE, by a net movement of positive charge across the membrane. It is a major component of the PROTON MOTIVE FORCE in MITOCHONDRIA used to drive the synthesis of ATP.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Choline: A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Exocytosis: Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.Receptors, Cell Surface: Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.Endosomes: Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.Anion Exchange Protein 1, Erythrocyte: A major integral transmembrane protein of the ERYTHROCYTE MEMBRANE. It is the anion exchanger responsible for electroneutral transporting in CHLORIDE IONS in exchange of BICARBONATE IONS allowing CO2 uptake and transport from tissues to lungs by the red blood cells. Genetic mutations that result in a loss of the protein function have been associated with type 4 HEREDITARY SPHEROCYTOSIS.Ions: An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.Hemolysis: The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Cytoskeleton: The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.Anions: Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.Static Electricity: The accumulation of an electric charge on a objectPatch-Clamp Techniques: 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.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Membrane Proteins: 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.Lipids: A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)Unilamellar Liposomes: Single membrane vesicles, generally made of PHOSPHOLIPIDS.Sodium-Potassium-Exchanging ATPase: 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.Spectrin: A high molecular weight (220-250 kDa) water-soluble protein which can be extracted from erythrocyte ghosts in low ionic strength buffers. The protein contains no lipids or carbohydrates, is the predominant species of peripheral erythrocyte membrane proteins, and exists as a fibrous coating on the inner, cytoplasmic surface of the membrane.Halobacterium: A genus of HALOBACTERIACEAE whose growth requires a high concentration of salt. Binary fission is by constriction.Immunoblotting: Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Magnesium: 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.Molecular Structure: 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.COS Cells: CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)Microscopy, Electron, Scanning: Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.Actins: Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Cations: Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Epithelium: One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.beta-Cyclodextrins: Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.Hydrogen Bonding: 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.Epithelial Cells: Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.Nigericin: A polyether antibiotic which affects ion transport and ATPase activity in mitochondria. It is produced by Streptomyces hygroscopicus. (From Merck Index, 11th ed)Freeze Etching: A replica technique in which cells are frozen to a very low temperature and cracked with a knife blade to expose the interior surfaces of the cells or cell membranes. The cracked cell surfaces are then freeze-dried to expose their constituents. The surfaces are now ready for shadowing to be viewed using an electron microscope. This method differs from freeze-fracturing in that no cryoprotectant is used and, thus, allows for the sublimation of water during the freeze-drying process to etch the surfaces.Osmolar Concentration: 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.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Binding, Competitive: The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Osmosis: Tendency of fluids (e.g., water) to move from the less concentrated to the more concentrated side of a semipermeable membrane.Proteolipids: Protein-lipid combinations abundant in brain tissue, but also present in a wide variety of animal and plant tissues. In contrast to lipoproteins, they are insoluble in water, but soluble in a chloroform-methanol mixture. The protein moiety has a high content of hydrophobic amino acids. The associated lipids consist of a mixture of GLYCEROPHOSPHATES; CEREBROSIDES; and SULFOGLYCOSPHINGOLIPIDS; while lipoproteins contain PHOSPHOLIPIDS; CHOLESTEROL; and TRIGLYCERIDES.Hydrophobic and Hydrophilic Interactions: The thermodynamic interaction between a substance and WATER.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Sodium-Hydrogen Antiporter: A plasma membrane exchange glycoprotein transporter that functions in intracellular pH regulation, cell volume regulation, and cellular response to many different hormones and mitogens.Aquaporins: A class of porins that allow the passage of WATER and other small molecules across CELL MEMBRANES.Creatine: An amino acid that occurs in vertebrate tissues and in urine. In muscle tissue, creatine generally occurs as phosphocreatine. Creatine is excreted as CREATININE in the urine.Lysosomes: A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Nictitating Membrane: A fold of the mucous membrane of the CONJUNCTIVA in many animals. At rest, it is hidden in the medial canthus. It can extend to cover part or all of the cornea to help clean the CORNEA.Bruch Membrane: The inner layer of CHOROID, also called the lamina basalis choroideae, located adjacent to the RETINAL PIGMENT EPITHELIUM; (RPE) of the EYE. It is a membrane composed of the basement membranes of the choriocapillaris ENDOTHELIUM and that of the RPE. The membrane stops at the OPTIC NERVE, as does the RPE.Guinea Pigs: A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.GTP-Binding Proteins: Regulatory proteins that act as molecular switches. They control a wide range of biological processes including: receptor signaling, intracellular signal transduction pathways, and protein synthesis. Their activity is regulated by factors that control their ability to bind to and hydrolyze GTP to GDP. EC 3.6.1.-.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Proteins: 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.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Ion Channel Gating: 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.Halobacterium salinarum: A species of halophilic archaea found in salt lakes. Some strains form a PURPLE MEMBRANE under anaerobic conditions.Sphingomyelins: A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.Cercopithecus aethiops: A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.Histidine: An essential amino acid that is required for the production of HISTAMINE.Electron Spin Resonance Spectroscopy: 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.Microsomes: Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Cell Polarity: Orientation of intracellular structures especially with respect to the apical and basolateral domains of the plasma membrane. Polarized cells must direct proteins from the Golgi apparatus to the appropriate domain since tight junctions prevent proteins from diffusing between the two domains.Microscopy, Electron, Transmission: Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Potassium Channels: 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.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Fluoresceins: A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.Neurons: 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.Porins: Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Complement Membrane Attack Complex: A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone: A proton ionophore that is commonly used as an uncoupling agent in biochemical studies.Organelles: Specific particles of membrane-bound organized living substances present in eukaryotic cells, such as the MITOCHONDRIA; the GOLGI APPARATUS; ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.Phosphatidylglycerols: A nitrogen-free class of lipids present in animal and particularly plant tissues and composed of one mole of glycerol and 1 or 2 moles of phosphatidic acid. Members of this group differ from one another in the nature of the fatty acids released on hydrolysis.Osmotic Fragility: RED BLOOD CELL sensitivity to change in OSMOTIC PRESSURE. When exposed to a hypotonic concentration of sodium in a solution, red cells take in more water, swell until the capacity of the cell membrane is exceeded, and burst.Transport Vesicles: Vesicles that are involved in shuttling cargo from the interior of the cell to the cell surface, from the cell surface to the interior, across the cell or around the cell to various locations.
Proton conducting membranes used in fuel cells. Antistatic / anti-reflection coatings Corrosion protection Porous hybrid ... solar cells, gas sensors and field effect transistors. Fire retardant materials for construction industry. Nanocomposite based ...
"System integration of China's first proton exchange membrane fuel cell locomotive". International Journal of Hydrogen Energy. ... "Japanese fuel cell rail vehicle in running tests". Fuel Cells Bulletin. 2006 (12): 2-3. 2006. doi:10.1016/S1464-2859(06)71254-8 ... PDF). Fuel Cell Today. "BNSF Railway and Vehicle Projects Demonstrate Experimental Hydrogen-Fuel-Cell Switch Locomotive." BNSF ... "Fuel-Cell-Powered Mine Locomotive." Sandia National Laboratories, 2004. "Development of the World's First Fuel Cell Hybrid ...
The fuel cell is a proton exchange membrane fuel cell (PEMFC). The Hyundai ix35 FCEV is in production since 2013, a production ... The Tucson Fuel Cell Electric Vehicle (FCEV) is a test fuel cell vehicle for Hyundai's 2nd generation hydrogen fuel cell. The ... List of fuel cell vehicles Hyundai aims to sell 10,000 FCEVs in South Korea by 2025 Hyundai fcev deployment First production ... The Hyundai ix35 fuel cell electric vehicle won the Future Auto accolade at the 2013 Brussels Motor Show. The first Hyundai ...
Brown D, Lui B, Gluck S, Sabolić I (Oct 1992). "A plasma membrane proton ATPase in specialized cells of rat epididymis". The ... Wieczorek H, Brown D, Grinstein S, Ehrenfeld J, Harvey WR (Aug 1999). "Animal plasma membrane energization by proton-motive V- ... Nishi T, Forgac M (Feb 2002). "The vacuolar (H+)-ATPases--nature's most versatile proton pumps". Nature Reviews Molecular Cell ... Nelson N, Harvey WR (Apr 1999). "Vacuolar and plasma membrane proton-adenosinetriphosphatases". Physiological Reviews. 79 (2): ...
CsHSO4 is considered to be prime candidate for proton transferring agent in proton exchange membrane fuel cells (PEMFC). ... "CsHSO4 as proton conductor for high-temperature polymer electrolyte membrane fuel cells." Journal of Applied Electrochemistry ... "CsHSO4 as proton conductor for high-temperature polymer electrolyte membrane fuel cells." Journal of Applied Electrochemistry ... fuel cells, electrocatalytic reactors, and batteries. Solid state proton conductors rely on the movement of protons, which are ...
It uses a proton-exchange membrane fuel cell to generate about 200 Watts. It can reach approximately 25 km/h and, on a full ... The PHB is a hydrogen bicycle, power-assisted by an electric motor that gets its electricity from a fuel cell. It is ... As stated by the manufacturer, those who already have a bike don't need to change the original frame structure; the fuel cell ... Hydrogen vehicle Pearl Hydrogen Hydrogen Fuel Cell Bicycle, Ecogeek Pearl Hydrogen China Valeswood ETD Ltd, UK Shanghai Daily. ...
Most hydrogen fuel cells today are of the proton exchange membrane (PEM) type. A PEM converts the chemical energy released ... By 2013, there were more than 4,000 fuel cell forklifts in the US. Hydrogen fuel cells also have the potential to replace or ... FuelCells.org also provides a fuel cell Policy Activity Wrapup for fuel cells and hydrogen for the year 2010. This wrap-up ... The fuel cells made at this time were most similar to today's phosphoric acid fuel cells. ...
Signal transduction in phototaxis involves depolarization of the cell membrane. The retinylidene proteins of the animal kingdom ... Bacteriorhodopsin functions as a proton pump, whereas halorhodopsin act as a chloride pump. Their functions range from ... of the rod cells in the vertebrate retina absorbs green-blue light. The photopsins of the cone cells of the retina differ in a ... This change acts as a molecular switch to activate a signal transduction mechanism within the cell. Depending on the type of ...
Ballard Power's comparably scaled products are based on proton exchange membrane fuel cells. Ballard's 150 kW units are ... Sprint has been using fuel cell power since 2005. In 2009, Sprint's fuel cell program received a grant of $7.3 million from the ... "Topsoe Fuel Cell". Topsoefuelcell.com. Retrieved 2013-07-28. "Innovation: Bloom didn't start a fuel-cell revolution". February ... However, other solid oxide fuel cell producers have solved the problem of different expansion rates of cells in the past. Scott ...
The type of fuel cell used is a Proton Exchange Membrane Fuel Cell. The fuel cell stack has a power of 86 kilowatts. The ... The fuel cell was a PEFC (proton exchange membrane) manufactured by Ballard Power Systems. The fuel cell had power output of 78 ... This model used a fuel cell first developed in-house by Honda called the Honda FC Stack. The fuel cell was introduced in ... The 2005 FCX was the second-generation fuel-cell vehicle (FCV) from Honda. It was Honda's first fuel-cell vehicle powered by a ...
"Graphene-Carbon Nanotube Hybrids as Robust Catalyst Supports in Proton Exchange Membrane Fuel Cells". Journal of The ... high surface area conductive catalyst support for Proton Exchange Membrane Fuel Cells electrode applications with enhanced ... "The Direct Growth of Graphene-Carbon Nanotube Hybrids as Catalyst Support for High-Performance PEM Fuel Cells". ECS ...
"High temperature proton exchange membranes based on polybenzimidazoles for fuel cells". Progress in Polymer Science. 34 (5): ... PBI membranes are dense, with very low gas permeability. To be proton conductive, PBI usually is doped with acid. The higher ... Their blend membranes with PBI demonstrate high level acid-doping levels with thermal and extended stability, high proton ... In recent years, polybenzimidazole found its application as a membrane in fuel cells. Brinker and Robinson invented the first ...
5 October 2017). "Modelling and simulation of Proton Exchange Membrane fuel cell with serpentine bipolar plate using MATLAB". ... of porous flow field type separators using sintered Ni-based alloy powders on interfacial contact resistances and fuel cell ...
2004 - Geoffrey Ballard - Founder of Ballard Power Systems, developer of proton-exchange membrane fuel cell. 2007 - Geoffrey H ... Electrolysis Cell Design For Ion Exchange Membrane Chlor-Alkali Process in: Electrochemical Cell design. Boston, MA: Springer ... 1997 - Maomi Seko - Developer of ion exchange membranes for chlor-alkali process and president of Asahi Chemical Industry. 2002 ... 1991 - Hiroto Miyake - Developer and designer of Flemion membranes at Asahi Glass Co. 1994 - Gerhard Kreysa - Expert in ...
It uses a proton-exchange membrane fuel cell to generate about 8 hp or 6 kilowatts. The Discovery Channel has indicated it can ... "Fuel cell motorcycle". youtube.com. Retrieved 2006-10-11. Intelligent Energy Business Week article Fuel cell motorcycle, The ... The ENV (Emission Neutral Vehicle) is an electric motorcycle prototype powered by an hydrogen fuel cell. It was developed by ... Hydrogen vehicle "Fuel cell motorcycle". youtube.com. Retrieved 2006-10-11. "Intelligent Energy". Retrieved 2007-04-02. " ...
This function is also widely used in modeling two-phase flow of proton-exchange membrane fuel cells. A large degree of ... hydration is needed for good proton conductivity while large liquid water saturation in pores of catalyst layer or diffusion ...
The resulting proton gradient across the cell membrane is used to drive the synthesis of the energy carrier ATP. Thus, when ... Halobacteria also contain a protein called Bacteriorhodopsins which are light-driven proton pumps found on the cell membrane. ... a light-sensitive protein which provides chemical energy for the cell by using sunlight to pump protons out of the cell. ... Their cell walls are also quite different from those of bacteria, as ordinary lipoprotein membranes fail in high salt ...
"Clean hydrogen generation through the electrocatalytic oxidation of formic acid in a Proton Exchange Membrane Electrolysis Cell ... There are three main types of cells, solid oxide electrolysis cells (SOECs), polymer electrolyte membrane cells (PEM) and ... PEM electrolysis cells typically operate below 100 °C and are becoming increasingly available commercially. These cells have ... Using microbial fuel cells, wastewater or plants can be used to generate power. Biocatalysed electrolysis should not be ...
It uses water added to sodium borohydride which releases hydrogen fuel for a proton exchange membrane fuel cell. It can be re- ... Kits using copper-magnesium cells activated by water or the liquid sample itself are also in development. Another water- ...
The encoded protein is localized to the cell membrane and acts as a proton-linked transporter of bumetanide. Transport by the ...
Nanoparticle catalysts supported on gCN are under development for both proton exchange membrane fuel cells and water ... "Graphitic Carbon Nitride as a Catalyst Support in Fuel Cells and Electrolyzers". Electrochimica Acta. 222: 44-57. doi:10.1016/j ... combined with surface and intralayer reactivities make them potentially useful catalysts relying on their labile protons and ...
They drive the hyperpolarization of the cell membrane by secreting protons in presence of light. This process is associated to ... Orange: Extracelular region of cell membrane. It acts primarily as light-driven proton pump (opsin funcion) when hit by yellow ... There were various studies applied on the membrane of H.salinarum to decipher the mechanism of light-driven proton pump. The ... Another kind of these light-driven proton pumps is Archaerhodopsin-2 (aR 2) which was found in the claret membrane of ...
The water will then move into the plant cell via osmosis. A cell membrane consists of many transport proteins that allow for ... It is believed to act as a symporter for protons and the potassium ion, K+. HAK5 transporter is one of four different types of ... High Affinity K+ transporter HAK5 is a transport protein found on the cell surface membrane of plants. ... In animal cells the toll-like receptor TLR4 binds the bacterial PAMP LPS (lipopolysaccharide) and induces K+ efflux through the ...
A typical plant cell contains about 10 to 100 chloroplasts. The chloroplast is enclosed by a membrane. This membrane is ... In addition, this creates a proton gradient (energy gradient) across the chloroplast membrane, which is used by ATP synthase in ... In its simplest form, this involves the membrane surrounding the cell itself. However, the membrane may be tightly folded into ... 3 ions are made from CO2 outside the cell by another carbonic anhydrase and are actively pumped into the cell by a membrane ...
It acts as a proton pump; that is, it captures light energy and uses it to move protons across the membrane out of the cell. ... Asp85 becomes a proton acceptor of the donor proton from the retinal molecule. This releases a proton from a "holding site" ... The resulting proton gradient is subsequently converted into chemical energy. Bacteriorhodopsin is an integral membrane protein ... This results in a second proton being released to the EC side. Asp85 releases its proton into the "holding site," where a new ...
The balance between potassium and sodium is maintained by ion transporter proteins in the cell membrane.[231] The cell membrane ... Indeed, transferring of protons between chemicals is the basis of acid-base chemistry.[10]:43 Also unique is hydrogen's ability ... Potassium is the major cation (positive ion) inside animal cells,[223] while sodium is the major cation outside animal cells.[ ... Unit cell ball-and-stick model of lithium nitride.[118] On the basis of size a tetrahedral structure would be expected, but ...
Integrin signaling and membrane blebbing modulate cell adhesion, spreading, and migration. However, the relationship between ... Sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are membrane proteins located on the bleb membrane. ... Sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are membrane proteins located on the bleb membrane. ... Sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are membrane proteins located on the bleb membrane. ...
Cell membrane Forum. • Covalent Forum. • Pharmacokinetic Forum. • Elimination half-life Forum. • Omeprazole Forum. • ... This forum is a place where people who are interested in Proton pump inhibitor come together and discuss about Proton pump ... Proton pump Forum. • Hydrogen Forum. • Potassium Forum. • ATPase Forum. • Enzyme Forum. • Hydrogen potassium ATPase Forum. • ... Parietal cell Forum. • H2 antagonist Forum. • Duodenum Forum. • Heartburn Forum. • Hypochlorhydria Forum. • Hydrochloric acid ...
H. Dai, H.M. Zhang, Q.T. Luo, Y. Zhang, C. Bi, Properties and fuel cell performance of proton exchange membranes prepared from ... Zhang Y., Xue R., Yuan W., Liu X. (2018) Nanomaterials in Proton Exchange Membrane Fuel Cells. In: Li F., Bashir S., Liu J. ( ... Although significant advancements have been achieved for proton exchange membrane fuel cells (PEMFCs) in recent years, PEMFCs ... Z. Yuan, Y. Zhang, J. Leng, Y. Gao, X. Liu, Development of a 4-cell air-breathing micro direct methanol fuel cell stack. J. ...
... sensing device for determining the amount of humidity in at least one primary fluid stream that is passed to a fuel cell stack ... 154 for ensuring the proper operation of the membranes in the fuel cells in the fuel cell stack 108. The first humidity sensor ... Fuel cell system. 2004-09-23. Enjoji et al.. 6706430. Electronic by-pass of fuel cell cathode gas to combustor. 2004-03-16. ... It is also known that the membranes within the fuel cell stack are kept moist to facilitate performance and to prevent damage. ...
Proton conductivity declines as water content decreases In DMFC methanol can permeate membrane Chemically degrades over time as ... cell using n-type TiO2 and p-type NiO . Fielden What are the advantages and disadvantages of a tandem cell in comparison to a ... Calculate the current and power when the cell is operated at 0.8 V and maximum power of the fuel cell. i = (VOC - Vcell) / k ... operated at 0.8 V and maximum power of the fuel cell. . Wildgoose A hydrogen fuel cell has been constructed and approximations ...
Among the different fuel cell types, the proton exchange membrane (PEM) fuel cell has shown great potential in mobile ... Proton Exchange Membrane Fuel Cells Modeling. Fengge Gao, Benjamin Blunier, Abdellatif Miraoui ... The fuel cell is a potential candidate for energy storage and conversion in our future energy mix. It is able to directly ... Part 3: 1D Dynamic Model of a Nexa Fuel Cell Stack 147 ... Part 2: Modeling of the Proton Exchange Membrane Fuel Cell 47. ...
The Global Proton Exchange Membrane Fuel Cells Industry 2015 Market Research Report is a professional - Market Research Reports ... 1.3 Applications of Proton Exchange Membrane Fuel Cells. 1.4 Industry Chain Structure of Proton Exchange Membrane Fuel Cells. ... Figure Proton Exchange Membrane Fuel Cells Picture and Specifications of Plug Power. Table Proton Exchange Membrane Fuel Cells ... Figure Picture of Proton Exchange Membrane Fuel Cells. Table Specifications of Proton Exchange Membrane Fuel Cells. Table ...
A receptor for protons in the nerve cell membrane.. Krishtal OA, Pidoplichko VI. ...
Influence of Carbon Support on Catalytic Layer Performance of Proton Exchange Membrane Fuel Cells. ... K.G. Nishanth, P. Sridhar, S. Pitchumani, A.K. Shukla, Fuel Cells 12, 146 (2012)CrossRefGoogle Scholar ... PEM fuel cell electrocatalysts and catalyst layers (Springer Publisher, New York, 2008)Google Scholar ... PEM fuel cell Pt/C Carbon support Carbon nanotubes Catalytic layer structure ...
For PEM Fuel Cells to attain economic viability for mass production, catalyst cost must be reduced. Currently, platinum-based ... In addition, new developments in membrane technology highlight the need to explore the performance of catalysts in a higher ... Finally, the behaviour and stability of selected catalysts will be assessed within the single cell environment and their ... NMP-2004-3.4.5.1 - Basic materials and industrial process research on functional materials for fuel cells ...
Proton exchange membrane fuel cells (PEMFC), Wetting, Bipolar plates, Electrical conductivity, Electroplated coating, Proton ... 1. Ammonia contamination of a proton exchange membrane fuel cell. Open this publication in new window or tab ,,Ammonia ... The proton exchange membrane (PEM) fuel cell is an electrochemical device that converts chemical energy into electrical energy ... On Gas Contaminants, and Bipolar Plates in Proton Exchange Membrane Fuel Cells. Acevedo Gomez, Yasna KTH, School of Engineering ...
... membrane electrode assembly (MEA) components should reach $2.6 billion by 2022 from $766 million in 2017 at a compound annual ... The global market for proton exchange membrane fuel cell (PEMFC) ... Proton Exchange Membrane Fuel Cell Companies. *Proton Exchange ... Materials for Proton Exchange Membranes and Membrane Electrode Assemblies for PEM Fuel Cells. Jul 2018, FCB035F, BCC Publishing ... The global proton exchange membrane fuel cell (PEMFC) and membrane electrode assembly (MEA) market reached $444 million in 2012 ...
This paper presents a dynamic modeling of a proton exchange membrane fuel cell (PEMFC) for transportation applications. Based ...
The bipolar plate is a key component in this device, as it connects each cell electrically, supplies reactant gases to both ... The proton exchange membrane fuel cell offers an exceptional potential for a clean, efficient, and reliable power source. ... anode and cathode, and removes reaction products from the cell. Bipolar plates have been fabricated primarily from high-density ... T. Cheng, "Bipolar plates and plate materials," in Proton Exchange Membrane Fuel Cells: Materials Properties and Performance, D ...
... the reliability study presented in this work consisted of performing life tests with single proton exchange membrane fuel cells ... Although the results indicated that fuel cell performance and durability were still at a level below the targets normally ... of the fuel cells was calculated. It is important to point out that the tests performed under the scope of this study were the ... which can be implemented as part of a reliability growth analysis of the fuel cells and can be integrated into the design ...
V. Gurau, S. Kakac, and H. Liu, "Mathematical model for proton exchange membrane fuel cells," in Proceedings of the ASME ... Optimum Alkaline Electrolyzer-Proton Exchange Membrane Fuel Cell Coupling in a Residential Solar Stand-Alone Power System. Hany ... D. Thirumalai and R. E. White, "Mathematical modeling of proton-exchange-membrane fuel-cell stacks," Journal of the ... J. Kim, S. M. Lee, S. Srinivasan, and C. E. Chamberlin, "Modeling of proton exchange membrane fuel cell performance with an ...
Your students will love seeing an eggs shell dissolve in vinegar exposing the cell membrane. Students rush to class to see the ... Your students will love seeing an eggs shell dissolve in vinegar exposing the cell membrane. Students rush to class to see the ... Teach about cells with this engaging lab that uses a raw chicken egg and everyday materials! ... Teach about cells with this engaging lab that uses a raw chicken egg and everyday materials! ...
New Anhydrous Proton Exchange Membrane for Intermediate Temperature Proton Exchange Membrane Fuel Cells Volume 12, Issue 6, ... Corrigendum: New Anhydrous Proton Exchange Membrane for Intermediate Temperature Proton Exchange Membrane Fuel Cells. Authors. ... In Section 2.3, paragraph 2, the first sentence should read: "Comparing the results (Figure 5), the membranes all has a qmax ... SAXS profiles of PVDF/PEO/DBS-H membranes at room temperature.. In the Experimental Section, paragraph 3, the fifth sentence ...
Fuel cell temperature during operation was 27 °C, as measured using thermocouples in contact with the backside of the electrode ... Fuel cell operating temperature measured in situ was 30.5 °C. ... a bipolar plate to measure the temperature inside the fuel cell ... in a micro fuel cell using the micro-electro-mechanical-systems (MEMS) fabrication technique. The resistance temperature ...
Electrochemical study of highly durable cathode with Pt supported on ITO-CNT composite for proton exchange membrane fuel cells ... "Activity and durability of Pt-Ni nanocage electocatalysts in proton exchange membrane fuel cells". Netherlands. doi:10.1016/j. ... title = {Activity and durability of Pt-Ni nanocage electocatalysts in proton exchange membrane fuel cells},. author = {Peng, ... Title: Activity and durability of Pt-Ni nanocage electocatalysts in proton exchange membrane fuel cells. ...
The topic of this thesis is the degradation of fuel cell electrodes in proton exchange membrane fuel cells (PEMFCs). In ... 1. Electrode degradation in proton exchange membrane fuel cells. Åpne denne publikasjonen i ny fane eller vindu ,,Electrode ... Operating conditions affecting the contact resistance of bi-polar plates in proton exchange membrane fuel cells. Oyarce, ... degradation in proton exchange membrane fuel cells. Oyarce, Alejandro. KTH, Skolan för kemivetenskap (CHE), Kemiteknik, ...
Tag: proton exchange membrane fuel cells. Global PEMFC (Proton Exchange Membrane Fuel Cells) Market to grow at a CAGR of 26.67 ... proton exchange membrane fuel cells, share, size, trendsLeave a comment Global Proton Exchange Membrane Fuel Cells Industry ... fuel cell market, fuel cells, global fuel cell market, hydrogen fuel, hydrogen fuel news, proton exchange membrane fuel cells, ... proton exchange membrane fuel cells, Stationary fuel cellsLeave a comment Fuel cell market to experience strong growth through ...
... proton exchange membrane fuel cell (PEMFC), fuel cell energy systems, clean manufacturing, engineering, energy technology ... Capstone Senior Design - Supramolecular Proton Exchange Membranes for Fuel Cells. EPA Grant Number: SU831899. Title: Capstone ... Supramolecular Proton Exchange Membranes for Fuel Cells. Investigators: Fuchs, Alan , Gecol, Hatice , Whiting, Wallace ... fuel cells. PEMs are the most widely used membranes for fuel cell applications because of their low operating temperature and ...
Proton Exchange Membrane Fuel Cells (PEMFC) are promising energy converters, but still suffer from a short life duration. ...
This minireview article summarises recent developments into carbon nanotube-based support materials for PEM fuel cells, ... including the membrane electrode assembly (MEA). The advan ... great influence on the performance and durability of proton ... proton. exchange membrane. fuel. cells. W. Zhang, P. Sherrell, A. I. Minett, J. M. Razal and J. Chen, Energy Environ. Sci., ... proton. exchange membrane. (. PEM. ) fuel. cells. . This minireview article summarises recent developments into carbon nanotube ...
  • This non-humidified proton conduction membrane comprises a polymer and a proton-conductive substance. (go.jp)
  • 2. The aforementioned 2nd region has the basic basis as the aforementioned functional group, the aforementioned proton discharge binding site has the acidic basis as the aforementioned functional group, In claim 1 non humidification type proton conduction membrane of statement. (go.jp)
  • 3. The aforementioned basic basis is containing nitrogen complex ring, the aforementioned acidic basis carbon acid radical and phosphorus acid radical, is at least one of sulfonate group and the sulfonyl imido basis, In claim 2 non humidification type proton conduction membrane of statement. (go.jp)
  • 5. The aforementioned proton coordinated region, is at least one of ether linkage, the ester basis, the alcoholic basis, the ketone group and the amide basis, Either of claim 1-4 in 1 sections non humidification type proton conduction membrane of statement. (go.jp)
  • suggested that the conduction mechanism involves the exchange of protons between the His37 imidazole moieties of M2 and waters confined to the M2 bundle interior. (wikipedia.org)
  • A collective switch of hydrogen bond orientations may contribute to the directionality of proton flux as His37 is dynamically protonated and deprotonated in the conduction cycle. (wikipedia.org)
  • The examination of the synthesized catalysts in a catalytic membrane electrode assembly layer reveals that CNTs favor a power density higher than in the carbon black support owing to a more suitable porous structure of the catalyst layer. (springer.com)
  • Finally, the behaviour and stability of selected catalysts will be assessed within the single cell environment and their potential for large-scale production investigated. (europa.eu)
  • The experimental part of this thesis focuses on the development an assessment of alternative cathode catalysts for PEM fuel cells. (bl.uk)
  • Finally, the activity of selected catalysts has been assessed through testing two catalyst candidates in a small scale PEM fuel cell. (bl.uk)
  • Developers are currently exploring platinum/ruthenium catalysts that are more resistant to CO.PEM fuel cells are used primarily for transportation applications and some stationary applications. (scribd.com)
  • As long as membrane catalysts are not poisoned by ions, cell stack efficiency and lifetime can be ensured for over 60,000 hours. (arevah2gen.com)
  • In Arabidopsis suspension cells a rapid plasma membrane depolarization is triggered by abscisic acid (ABA). (plantphysiol.org)
  • Activation of anion channels was shown to be a component leading to this ABA-induced plasma membrane depolarization. (plantphysiol.org)
  • Using experiments employing combined voltage clamping, continuous measurement of extracellular pH, we examined whether plasma membrane H + -ATPases could also be involved in the depolarization. (plantphysiol.org)
  • Inhibition of the proton pump by ABA is thus a second component leading to the plasma membrane depolarization. (plantphysiol.org)
  • Both R-type and S-type channels have been suggested to contribute to an initial phase of the depolarization, while maintenance of the depolarized state of the plasma membrane was only attributed to the S-type anion channels ( Schroeder and Keller, 1992 ). (plantphysiol.org)
  • Some of the anion channels involved in a long-term plasma membrane depolarization are Ca 2+ -sensitive and therefore are activated by an increase in cytoplasmic calcium concentration. (plantphysiol.org)
  • These depolarizations are due to modifications of plasma membrane ion channel activities. (plantphysiol.org)
  • However, for most of these examples, ion channel modulation is not the single mechanism responsible for the plasma membrane depolarization. (plantphysiol.org)
  • Immunocytological localization of an epitope-tagged plasma membrane proton pump (H(+)-ATPase) in phloem companion cells. (plantcell.org)
  • In higher plants, the plasma membrane proton pump (H(+)-ATPase) is encoded by a surprisingly large multigene family whose members are expressed in different tissues. (plantcell.org)
  • Immunofluorescence studies with tissue sections of transgenic plants have revealed that c-Myc-tagged AHA3 is restricted to the plasma membrane of phloem companion cells, whereas other AHA isoproteins are more widely distributed in the plasma membrane of other cell types. (plantcell.org)
  • Electron microscopy with immunogold-labeled tissue sections suggests that there is a high concentration of proton pumps in the plasma membrane of companion cells but a much lower concentration in the plasma membrane of sieve elements. (plantcell.org)
  • Due to plasmodesmata connecting the plasma membrane of these two adjacent cell types, it is likely that the proton motive force generated by the proton pump in companion cells can serve to power the uptake of sugar by proton-coupled symporters in either the companion cell or sieve element cell. (plantcell.org)
  • The abundance of the proton pump in the plasma membrane of companion cells supports an apoplastic model for phloem loading in which the metabolic energy that drives sugar uptake is consumed by AHA3 at the companion cell plasma membrane. (plantcell.org)
  • These experiments with a genetically altered integral plasma membrane protein demonstrate the utility of using a short c-Myc sequence as an epitope tag in Arabidopsis. (plantcell.org)
  • Furthermore, our results demonstrate that, using genes encoding individual members of a gene family, it is possible to label plasma membrane proteins immunologically in specific, differentiated cell types of higher plants. (plantcell.org)
  • These cells contain a population of characteristic tubulovesicles that are believed to be involved in the shuttling of proton pumps (H+ATPase) to and from the plasma membrane. (escholarship.org)
  • These transporting vesicles have a dense, studlike material coating the cytoplasmic face of their limiting membranes and similar studs are also found beneath parts of the plasma membrane. (escholarship.org)
  • Similar arrays of studs were also found on vesicles trapped in the residual band of cytoplasm that remained attached to the underside of the plasma membrane, but none were seen in adjacent granular cells. (escholarship.org)
  • When overexpressed in yeast or plant protoplasts, the functional GFP-AAP3 fusion was localized in subcellular organelle-like structures, nuclear membrane, and plasma membrane. (nih.gov)
  • Epitope-tagged AAP3 confirmed its localization to the plasma membrane and nuclear membrane of the phloem, consistent with the promoter-GUS study. (nih.gov)
  • The solution cast dry films of the sulfonated polyimide membranes gave tough, ductile membranes and demonstrated moderate to high water absorption, which is necessary for PEM fuel cells. (openthesis.org)
  • The sulfonated five-membered polyimide membranes were aged in an air-oven at increasing temperatures (30-220 oC) for 30 min and then titrated with TMAH using non- aqueous potentiometric titration. (openthesis.org)
  • A humidity sensing device for determining the amount of humidity in at least one primary fluid stream that is passed to a fuel cell stack is provided. (freepatentsonline.com)
  • Such plates are by volume, weight, and cost the most critical component of a fuel cell stack [ 23 , 24 ], and account for more than 40% of the total stack cost and about 80% of the total weight [ 25 - 31 ]. (hindawi.com)
  • Bipolar plates perform a number of critical functions simultaneously in a fuel cell stack to ensure acceptable levels of power output and a long stack lifetime. (hindawi.com)
  • An exploded view of a PEM fuel cell stack is shown in Figure 1 . (hindawi.com)
  • After validation, the Ballard stack parameters were used in transient integration to evaluate how the fuel cell responds to rapid changes in load and flow conditions. (umd.edu)
  • This report documents research on component (fuel cell stack, fuel processor, power source ancillaries and system sensors) development and the 10-kW power source system integration and test. (unt.edu)
  • and successful integrated operation of a 10-kW fuel cell stack on reformate from the fuel processor. (unt.edu)
  • In previous works, the measurement of the complex impedance of a fuel cell stack during standby is used as an index of its membrane hydration status. (aau.dk)
  • In order to study the impact of these variations on stack performance, an extended mathematical model comprising two single cells and a coolant plate is considered. (ntu.edu.sg)
  • Several parameters are perturbed for one of the cells while the other is operating at base case conditions, an extension to larger stack units is also discussed. (ntu.edu.sg)
  • However, a small dissolution of Mo, Ru, Fe and W from the anodes and their migration toward cathodes during the cell operation is observed. (scielo.br)
  • Three different placements to incorporate the PANFs in the anodes include (1) placing a PANFs layer between catalyst layer (CL) and membrane, (2) coating the CL with PANFs and catalyst mixed slurry, and (3) placing a PANFs layer between the CL and gas diffusion layer (GDL). (elsevier.com)
  • Bipolar plates form an integral part of a fuel cell and their high manufacturing cost and low production rate have hindered the commercialization of fuel cells. (utexas.edu)
  • Furthermore, the platinum catalyst on the membrane is easily poisoned by carbon monoxide (no more than one part per million is usually acceptable) and the membrane is sensitive to things like metal ions, which can be introduced by corrosion of metallic bipolar plates, metallic components in the fuel cell system or from contaminants in the fuel / oxidant. (chemeurope.com)
  • Both ex-situ and in-situ measurements of contact resistance between gas diffusion layer (GDL) and bi-polar plate (BPP) were carried out using the same fuel cell hardware. (diva-portal.org)
  • Increasing cell temperatures and relative humidity (RH) of the gases lowered the contact resistance. (diva-portal.org)
  • In the case of uncoated steel 316L and gold-coated steel 316L, high current density operation for an extended period of time also caused a progressive deterioration of the contact resistance, which without this in-situ measurement could have been mistaken for other ohmic losses, e.g. increased membrane resistance due to metal ion poisoning. (diva-portal.org)
  • C ) Changes in the cell voltage (solid symbols) and ohmic resistance (open symbols) of the SPP-QP cell (IEC = 2.6 mmol g −1 ) at 80°C and 30% RH (H 2 /air). (sciencemag.org)
  • In low operating temperatures the resistance within the membrane increases and this could cause rapid decrease in potential. (thescipub.com)
  • Another significant source of losses is the resistance of the membrane to proton flow, which is minimized by making it as thin as possible, on the order of 50 μm. (chemeurope.com)
  • This book presents a detailed state of art of PEM fuel cell modeling, with very detailed physical phenomena equations in different physical domains. (wiley.com)
  • Water content in the fuel cell is given basically by the generation of the water in the cathode due to the reaction, the humidity of the inlet gases and the transport trough the membrane. (csic.es)
  • IR -included H 2 /O 2 polarization curves (solid symbols) and ohmic resistances (open symbols) of the SPP-QP cell (IEC = 2.6 mmol g −1 ) at 80°C under humidity conditions of ( A ) 100% RH and ( B ) 30% RH. (sciencemag.org)
  • The cell potential increases with relative humidity and improved hydration which reduces ohmic losses. (thescipub.com)