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Bioelectrochemistry
Bioelectrochemistry is a branch of electrochemistry and biophysical chemistry concerned with electrophysiological topics like cell electron-proton transport, cell membrane potentials and electrode reactions of redox enzymes. History The beginnings of bioelectrochemistry, as well as those of electrochemistry, are closely related to physiology through the works of Luigi Galvani and then Alessandro Volta. The first modern work in this field is considered that of the German physiologist Julius Bernstein (1902) concerning the source of biopotentials due to different ion concentration through the cell's membrane. The domain of bioelectrochemistry has grown considerably over the past century, maintaining the close connections to various medical and biological and engineering disciplines like electrophysiology, biomedical engineering, and enzyme kinetics. The achievements in this field have been awarded several Nobel prizes for Physiology or Medicine. Among prominent electrochemists wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioelectrochemistry
Bioelectrochemistry is a branch of electrochemistry and biophysical chemistry concerned with electrophysiological topics like cell electron-proton transport, cell membrane potentials and electrode reactions of redox enzymes. History The beginnings of bioelectrochemistry, as well as those of electrochemistry, are closely related to physiology through the works of Luigi Galvani and then Alessandro Volta. The first modern work in this field is considered that of the German physiologist Julius Bernstein (1902) concerning the source of biopotentials due to different ion concentration through the cell's membrane. The domain of bioelectrochemistry has grown considerably over the past century, maintaining the close connections to various medical and biological and engineering disciplines like electrophysiology, biomedical engineering, and enzyme kinetics. The achievements in this field have been awarded several Nobel prizes for Physiology or Medicine. Among prominent electrochemists wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Film Voltammetry
In electrochemistry, protein film voltammetry (or protein film electrochemistry, or direct electrochemistry of proteins) is a technique for examining the behavior of proteins immobilized (either adsorbed or covalently attached) on an electrode. The technique is applicable to proteins and enzymes that engage in electron transfer reactions and it is part of the methods available to study enzyme kinetics. Provided that it makes suitable contact with the electrode surface (electron transfer between the electrode and the protein is direct) and provided that it is not denatured, the protein can be fruitfully interrogated by monitoring current as a function of electrode potential and other experimental parameters. Various electrode materials can be used. Special electrode designs are required to address membrane-bound proteins. Experiments with redox proteins Small redox proteins such as cytochromes and ferredoxins can be investigated on condition that their electroactive coverage ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioelectrochemical Reactor
A Bioelectrochemical reactor is a type of bioreactor where bioelectrochemical processes are used to degrade/produce organic materials using microorganisms. This bioreactor has two compartments: The anode, where the oxidation reaction takes place; And the cathode, where the reduction occurs. At these sites, electrons are passed to and from microbes to power reduction of protons, breakdown of organic waste, or other desired processes. They are used in microbial electrosynthesis, environmental remediation, and electrochemical energy conversion. Examples of bioelectrochemical reactors include microbial electrolysis cells, microbial fuel cells, enzymatic biofuel cells, electrolysis cells, microbial electrosynthesis cells, and biobatteries. Principles Electron current is inherent to microbial metabolism. Microorganisms transfer electrons from an electron donor (lower potential species) to an electron acceptor (higher potential species). If the electron acceptor is an external ion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymatic Biofuel Cell
An enzymatic biofuel cell is a specific type of fuel cell that uses enzymes as a catalyst to oxidize its fuel, rather than precious metals. Enzymatic biofuel cells, while currently confined to research facilities, are widely prized for the promise they hold in terms of their relatively inexpensive components and fuels, as well as a potential power source for bionic implants. Operation Enzymatic biofuel cells work on the same general principles as all fuel cells: use a catalyst to separate electrons from a parent molecule and force it to go around an electrolyte barrier through a wire to generate an electric current. What makes the enzymatic biofuel cell distinct from more conventional fuel cells are the catalysts they use and the fuels that they accept. Whereas most fuel cells use metals like platinum and nickel as catalysts, the enzymatic biofuel cell uses enzymes derived from living cells (although not within living cells; fuel cells that use whole cells to catalyze fuel are c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Bockris
Bernhardt Patrick John O’Mara Bockris (5 January 1923 – 7 July 2013) was a South African professor of chemistry, latterly at Texas A&M University. During his long and prolific career he published some 700 papers and two dozen books. His best known work is in electrochemistry but his output also extended to environmental chemistry, photoelectrochemistry and bioelectrochemistry. In the 1990s he experimented with cold fusion and transmutation, topics on which his unorthodox views provoked controversy. Early life John Bockris was born on 5 January 1923, in Johannesburg, South Africa. His mother was Emmeline Mary MacNally and his father Alfred Bockris. He attended a sequence of schools in Brighton, including the preparatory school Withdean Hall from 1934 to 1937, and Xaverian College, a Catholic secondary school, from 1937 to 1940. His father was not present during his childhood: His mother and aunt earned their income from tailoring. University education In 1940 Bockr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saltatory Conduction
In neuroscience, saltatory conduction () is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials. The uninsulated nodes of Ranvier are the only places along the axon where ions are exchanged across the axon membrane, regenerating the action potential between regions of the axon that are insulated by myelin, unlike electrical conduction in a simple circuit. Mechanism Myelinated axons only allow action potentials to occur at the unmyelinated nodes of Ranvier that occur between the myelinated internodes. It is by this restriction that saltatory conduction propagates an action potential along the axon of a neuron at rates significantly higher than would be possible in unmyelinated axons (150 m/s compared to 0.5 to 10 m/s). As sodium rushes into the node it creates an electrical force which pushes on the ions already inside the axon. This rapid conduction of electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomagnetism
Biomagnetism is the phenomenon of magnetic fields ''produced'' by living organisms; it is a subset of bioelectromagnetism. In contrast, organisms' use of magnetism in navigation is magnetoception and the study of the magnetic fields' ''effects'' on organisms is '' magnetobiology''. (The word biomagnetism has also been used loosely to include magnetobiology, further encompassing almost any combination of the words magnetism, cosmology, and biology, such as "magnetoastrobiology".) The origin of the word biomagnetism is unclear, but seems to have appeared several hundred years ago, linked to the expression "animal magnetism". The present scientific definition took form in the 1970s, when an increasing number of researchers began to measure the magnetic fields produced by the human body. The first valid measurement was actually made in 1963, but the field of research began to expand only after a low-noise technique was developed in 1970.{{cite journal , last1=Cohen , first1=David , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioelectronics
Bioelectronics is a field of research in the convergence of biology and electronics. Definitions At the first C.E.C. Workshop, in Brussels in November 1991, bioelectronics was defined as 'the use of biological materials and biological architectures for information processing systems and new devices'. Bioelectronics, specifically bio-molecular electronics, were described as 'the research and development of bio-inspired (i.e. self-assembly) inorganic and organic materials and of bio-inspired (i.e. massive parallelism) hardware architectures for the implementation of new information processing systems, sensors and actuators, and for molecular manufacturing down to the atomic scale'. The National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce, defined bioelectronics in a 2009 report as "the discipline resulting from the convergence of biology and electronics". Sources for information about the field include the Institute of Electri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrochemistry
Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outcome of a particular chemical change, or vice versa. These reactions involve electrons moving via an electronically-conducting phase (typically an external electrical circuit, but not necessarily, as in electroless plating) between electrodes separated by an ionically conducting and electronically insulating electrolyte (or ionic species in a solution). When a chemical reaction is driven by an electrical potential difference, as in electrolysis, or if a potential difference results from a chemical reaction as in an electric battery or fuel cell, it is called an ''electrochemical'' reaction. Unlike in other chemical reactions, in electrochemical reactions electrons are not transferred directly between atoms, ions, or molecules, but via th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrochemistry
Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outcome of a particular chemical change, or vice versa. These reactions involve electrons moving via an electronically-conducting phase (typically an external electrical circuit, but not necessarily, as in electroless plating) between electrodes separated by an ionically conducting and electronically insulating electrolyte (or ionic species in a solution). When a chemical reaction is driven by an electrical potential difference, as in electrolysis, or if a potential difference results from a chemical reaction as in an electric battery or fuel cell, it is called an ''electrochemical'' reaction. Unlike in other chemical reactions, in electrochemical reactions electrons are not transferred directly between atoms, ions, or molecules, but via th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julius Bernstein
Julius Bernstein (18 December 1839 – 6 February 1917) was a German physiologist born in Berlin. His father was Aron Bernstein (1812—1884), a founder of the Reform Judaism Congregation in Berlin 1845; his son was the mathematician Felix Bernstein (1878—1956). Academic career He studied medicine at the University of Breslau under Rudolf Heidenhain (1834-1897), and at the University of Berlin with Emil Du Bois-Reymond (1818-1896). He received his medical degree at Berlin in 1862, and two years later began work in the physiological institute at the University of Heidelberg as an assistant to Hermann von Helmholtz (1821-1894). In 1872 he succeeded Friedrich Goltz (1834-1902) as professor of physiology at the University of Halle, where in 1881 he founded an institute of physiology.Short biog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Potential
Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. That is, there is a difference in the energy required for electric charges to move from the internal to exterior cellular environments and vice versa, as long as there is no acquisition of kinetic energy or the production of radiation. The concentration gradients of the charges directly determine this energy requirement. For the exterior of the cell, typical values of membrane potential, normally given in units of milli volts and denoted as mV, range from –80 mV to –40 mV. All animal cells are surrounded by a membrane composed of a lipid bilayer with proteins embedded in it. The membrane serves as both an insulator and a diffusion barrier to the movement of ions. Transmembrane proteins, also known as ion transporter or ion pump proteins, actively push ions across the membrane and establish concentratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
