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Clark Electrode
The Clark electrode is an electrode that measures ambient oxygen partial pressure in a liquid using a catalytic platinum surface according to the net reaction: : O2 + 4 e− + 4 H+ → 2 H2O It improves on a bare platinum electrode by use of a membrane to reduce fouling and metal plating onto the platinum. History Leland Clark (Professor of Chemistry, Antioch College, Yellow Springs, Ohio, and Fels Research Institute, Yellow Springs, Ohio) had developed the first bubble oxygenator for use in cardiac surgery. However, when he came to publish his results, his article was refused by the editor since the oxygen tension in the blood coming out from the device could not be measured. This motivated Clark to develop the oxygen electrode. The electrode, when implanted in vivo, will reduce oxygen and thus required stirring in order to maintain an equilibrium with the environment. Severinghaus improved the design by adding a stirred cuvette in a thermostat. A discrepancy between the measu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clark Oxygen Electrode
Clark is an English language surname, ultimately derived from the Latin language, Latin with historical links to England, Scotland, and Ireland ''clericus'' meaning "scribe", "secretary" or a scholar within a religious order, referring to someone who was educated. ''Clark'' evolved from "clerk (position), clerk". First records of the name are found in 12th-century England. The name has many variants. ''Clark'' is the twenty-seventh most common surname in the United Kingdom, including placing fourteenth in Scotland. Clark is also an occasional given name, as in the case of Clark Gable. According to the 1990 United States Census, ''Clark'' was the twenty-first most frequently encountered surname, accounting for 0.23% of the population.United States Census Bureau (9 May 1995). s:1990 Census Name Files/dist.all.last (1-100). Retrieved on 2021-07-27. Notable people with the surname include: Disambiguation pages *Anne Clark (other), multiple people *Brian Clark (disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrode
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air). Electrodes are essential parts of batteries that can consist of a variety of materials depending on the type of battery. The electrophore, invented by Johan Wilcke, was an early version of an electrode used to study static electricity. Anode and cathode in electrochemical cells Electrodes are an essential part of any battery. The first electrochemical battery made was devised by Alessandro Volta and was aptly named the Voltaic cell. This battery consisted of a stack of copper and zinc electrodes separated by brine-soaked paper disks. Due to fluctuation in the voltage provided by the voltaic cell it wasn't very practical. The first practical battery was invented in 1839 and named the Daniell cell after John Frederic Daniell. Still making use of the zinc–copper electrode combination. Since then many more batteries have be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platinum
Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish , a diminutive of "silver". Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements. It has six naturally occurring isotopes. It is one of the rarer elements in Earth's crust, with an average abundance of approximately 5 μg/kg. It occurs in some nickel and copper ores along with some native deposits, mostly in South Africa, which accounts for ~80% of the world production. Because of its scarcity in Earth's crust, only a few hundred tonnes are produced annually, and given its important uses, it is highly valuable and is a major precious metal commodity. Platinum is one of the least reactive metals. It has remarkable resistance to corrosion, even at high temperatures, and is therefore considered a noble metal. Consequent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leland Clark
Leland C. Clark Jr. (December 4, 1918 – September 25, 2005) was an American biochemist born in Rochester, New York. He is most well known as the inventor of the Clark electrode, a device used for measuring oxygen in blood, water and other liquids. Clark is considered the "father of biosensors", and the modern-day glucose sensor used daily by millions of diabetics is based on his research. He conducted pioneering research on heart-lung machines in the 1940s and '50s and was holder of more than 25 patents. Although he developed a fluorocarbon-based liquid that could be breathed successfully by mice in place of air, his lifelong goal of developing artificial blood remained unfulfilled at the time of his death. He is the inventor of Oxycyte, a third-generation perfluorocarbon (PFC) therapeutic oxygen carrier designed to enhance oxygen delivery to damaged tissues. Professional life Clark received his B.S. degree in Chemistry from Antioch College in 1941 and his Ph.D. in Biochemistry a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioch College
Antioch College is a private liberal arts college in Yellow Springs, Ohio. Founded in 1850 by the Christian Connection, the college began operating in 1852 as a non-sectarian institution; politician and education reformer Horace Mann was its first president. The college has been politically liberal and reformist since its inception. It was the fourth college in the country to admit African-American students on an equal basis with whites. It has had a tumultuous financial and corporative history, closing repeatedly, for years at a time, until new funding was assembled. Antioch College began opening new campuses in 1964, when it purchased the Putney School of Education in Vermont. Eventually it opened over 38 different campuses, and in 1978 it changed its name to Antioch University. While most of the university's campuses focused on adult education, graduate programs, and degree completion, Antioch College remained a traditional undergraduate institution on the original campus. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellow Springs, Ohio
Yellow Springs is a village in Greene County, Ohio, United States. The population was 3,697 at the 2020 census. It is part of the Dayton Metropolitan Statistical Area. It is home to Antioch College. History The area of the village had long been visited and occupied by the Shawnee Native Americans well before European-American settlement. In 1825, the village was founded by William Mills and approximately 100 families, followers of Robert Owen, who wanted to emulate the utopian community at New Harmony, Indiana. The village was named after nearby natural springs with waters high in iron content. The communitarian efforts dissolved due to internal conflicts. The completion of the Little Miami Railroad in 1846 brought increased commerce, inhabitants, and tourism to this area of Greene County. Many regular visitors of the 19th century came for the springs, as these were believed to have medicinal benefits. The village of Yellow Springs was incorporated in 1856. Antioch Col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate (chemistry), substrate change. Oxidation is the loss of Electron, electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teflon
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. It is one of the best-known and widely applied PFAS. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off from DuPont, which originally discovered the compound in 1938. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high-molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine. PTFE has one of the lowest coefficients of friction of any solid. Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds, so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semipermeable Membrane
Semipermeable membrane is a type of biological or synthetic, polymeric membrane that will allow certain molecules or ions to pass through it by osmosis. The rate of passage depends on the pressure, concentration, and temperature of the molecules or solutes on either side, as well as the permeability of the membrane to each solute. Depending on the membrane and the solute, permeability may depend on solute size, solubility, properties, or chemistry. How the membrane is constructed to be selective in its permeability will determine the rate and the permeability. Many natural and synthetic materials which are rather thick are also semipermeable. One example of this is the thin film on the inside of the egg. Biological membranes are selectively permeable, with the passage of molecules controlled by facilitated diffusion, passive transport or active transport regulated by proteins embedded in the membrane. Biological membranes An example of a biological semi-permeable membrane is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucose Oxidase
The glucose oxidase enzyme (GOx or GOD) also known as notatin (EC number 1.1.3.4) is an oxidoreductase that catalyses the oxidation of glucose to hydrogen peroxide and D-glucono-δ-lactone. This enzyme is produced by certain species of fungi and insects and displays antibacterial activity when oxygen and glucose are present. Glucose oxidase is widely used for the determination of free glucose in body fluids (medical testing), in vegetal raw material, and in the food industry. It also has many applications in biotechnologies, typically enzyme assays for biochemistry including biosensors in nanotechnologies. It was first isolated by Detlev Müller in 1928 from ''Aspergillus niger''. Function Several species of fungi and insects synthesize glucose oxidase, which produces hydrogen peroxide, which kills bacteria. Notatin, extracted from antibacterial cultures of ''Penicillium notatum'', was originally named Penicillin A, but was renamed to avoid confusion with penicillin. Notati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
