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Frank H. Westheimer
Frank Henry Westheimer NAS ForMemRS APS (January 15, 1912 – April 14, 2007) was an American chemist. He taught at the University of Chicago from 1936 to 1954, and at Harvard University from 1953 to 1983, becoming the Morris Loeb Professor of Chemistry in 1960, and Professor Emeritus in 1983. The Westheimer medal was established in his honor in 2002. Westheimer did pioneering work in physical organic chemistry, applying techniques from physical to organic chemistry and integrating the two fields. He explored the mechanisms of chemical and enzymatic reactions, and made fundamental theoretical advances. Westheimer worked with John Gamble Kirkwood on the Bjerrum electrostatic analysis of carboxylic acids; with Joseph Edward Mayer on the calculation of molecular mechanics; explored the mechanisms of enzyme catalysis with Birgit Vennesland and determined the mechanisms of chromic acid oxidations and kinetic isotope effects. He received the National Medal of Science in 1986 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baltimore, Maryland
Baltimore ( , locally: or ) is the most populous city in the U.S. state of Maryland, fourth most populous city in the Mid-Atlantic, and the 30th most populous city in the United States with a population of 585,708 in 2020. Baltimore was designated an independent city by the Constitution of Maryland in 1851, and today is the most populous independent city in the United States. As of 2021, the population of the Baltimore metropolitan area was estimated to be 2,838,327, making it the 20th largest metropolitan area in the country. Baltimore is located about north northeast of Washington, D.C., making it a principal city in the Washington–Baltimore combined statistical area (CSA), the third-largest CSA in the nation, with a 2021 estimated population of 9,946,526. Prior to European colonization, the Baltimore region was used as hunting grounds by the Susquehannock Native Americans, who were primarily settled further northwest than where the city was later built. Colonis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nakanishi Prize
The Nakanishi Prize, named after Japanese chemist Koji Nakanishi, is an award in chemistry given alternately by the Chemical Society of Japan and the American Chemical Society. Purpose "To recognize and stimulate significant work that extends chemical and spectroscopic methods to the study of important biological phenomena." History In 1995, friends and colleagues of Nakanishi established the Nakanishi Prize. It was decided that the Chemical Society of Japan and the American Chemical Society would alternate years awarding the prize. There are two separate endowments for the prize for each society, but the prize is the same for both awards: a medallion in presentation box, $5,000 prize money, and $2,500 travel reimbursements. Recipients SourceAmerican Chemical Society See also * List of chemistry awards This list of chemistry awards is an index to articles about notable awards for chemistry. It includes awards by the Royal Society of Chemistry, the American Chemical So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birgit Vennesland
Birgit Vennesland (17 November 1913 — 15 October 2001) was a Norwegian-American biochemist. Vennesland spent the majority of her career as an academic for the University of Chicago from 1941 to 1968. While at Chicago, she compared the enzymes that animals use during metabolism and to the enzymes used by plants in photosynthesis. After leaving Chicago for Germany, Vennesland was the director of the Max Planck Institute for Cell Biology from 1968 to 1970. She later was the director of a eponymous research facility by the Max Planck Society from 1970 until her retirement in 1981. During her career, Vennesland received the Stephen Hales Prize from the American Society of Plant Biologists in 1950 and the Garvan-Olin Medal from the American Chemical Society in 1964. Early life and education On November 17, 1913, Vennesland was born in Kristiansand, Norway to Sigrid Kristine, a teacher, and Gunnuf Olaf, a timber merchant. For her first years, Vennesland grew up with her mother and twin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Catalysis
Enzyme catalysis is the increase in the rate of a process by a biological molecule, an "enzyme". Most enzymes are proteins, and most such processes are chemical reactions. Within the enzyme, generally catalysis occurs at a localized site, called the active site. Most enzymes are made predominantly of proteins, either a single protein chain or many such chains in a multi-subunit complex. Enzymes often also incorporate non-protein components, such as metal ions or specialized organic molecules known as cofactor (e.g. adenosine triphosphate). Many cofactors are vitamins, and their role as vitamins is directly linked to their use in the catalysis of biological process within metabolism. Catalysis of biochemical reactions in the cell is vital since many but not all metabolically essential reactions have very low rates when uncatalysed. One driver of protein evolution is the optimization of such catalytic activities, although only the most crucial enzymes operate near catalytic e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Mechanics
Molecular mechanics uses classical mechanics to model molecular systems. The Born–Oppenheimer approximation is assumed valid and the potential energy of all systems is calculated as a function of the nuclear coordinates using force fields. Molecular mechanics can be used to study molecule systems ranging in size and complexity from small to large biological systems or material assemblies with many thousands to millions of atoms. All-atomistic molecular mechanics methods have the following properties: * Each atom is simulated as one particle * Each particle is assigned a radius (typically the van der Waals radius), polarizability, and a constant net charge (generally derived from quantum calculations and/or experiment) * Bonded interactions are treated as ''springs'' with an equilibrium distance equal to the experimental or calculated bond length Variants on this theme are possible. For example, many simulations have historically used a ''united-atom'' representation in which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Edward Mayer
Joseph Edward Mayer (February 5, 1904, New York City – October 15, 1983) was a chemist who formulated the Mayer expansion in statistical field theory. He was professor of chemistry at the University of California San Diego from 1960 to 1972, and previously at Johns Hopkins University, Columbia University and the University of Chicago. He was married to Nobel Prize-winning physicist Maria Goeppert Mayer from 1930 until her death in 1972. He went to work with James Franck in Göttingen, Germany in 1929, where he met Maria, a student of Max Born. He was a member of the United States National Academy of Sciences (1946), the American Academy of Arts and Sciences (1958), and the American Philosophical Society (1970). Joseph Mayer was president of the American Physical Society from 1973 to 1975. Scientific contributions He developed the cluster expansion method and Mayer-McMillan solution theory. See also *Mayer f-function The Mayer f-function is an auxiliary function that often appe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Acids
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They at oftentimes have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid (C3H7CO2H) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bjerrum Length
The Bjerrum length (after Danish chemist Niels Bjerrum 1879–1958 ) is the separation at which the electrostatic interaction between two elementary charges is comparable in magnitude to the thermal energy scale, k_\text T, where k_\text is the Boltzmann constant and T is the absolute temperature in kelvins. This length scale arises naturally in discussions of electrostatic, electrodynamic and electrokinetic phenomena in electrolytes, polyelectrolytes and colloidal dispersions. In standard units, the Bjerrum length is given by \lambda_\text = \frac, where e is the elementary charge, \varepsilon_r is the relative dielectric constant of the medium and \varepsilon_0 is the vacuum permittivity. For water at room temperature \varepsilon_r \approx 80, so that In Gaussian units, 4\pi\varepsilon_0 = 1 and the Bjerrum length has the simpler form \lambda_\text = \frac. The relative permittivity ''ε''r of water decreases so strongly with temperature that the product (''ε''r· ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Gamble Kirkwood
John "Jack" Gamble Kirkwood (May 30, 1907, Gotebo, Oklahoma – August 9, 1959, New Haven, Connecticut) was a noted chemist and physicist, holding faculty positions at Cornell University, the University of Chicago, California Institute of Technology, and Yale University. Early life and background Kirkwood was born in Gotebo, Oklahoma, the oldest child of John Millard and Lillian Gamble Kirkwood. His father was educated as an attorney and was a distributor for the Goodyear Corporation in the state of Kansas. In addition to Jack Kirkwood, there were two younger sisters: Caroline (1910) and Margaret (1921). In 1909, the family moved to Wichita, Kansas. In the 1920s the family traveled to Pasadena, California to escape Midwestern winters. Education While in Pasadena, Kirkwood, age 15, audited chemistry classes at Caltech. Showing remarkable talent in mathematics and chemistry, Kirkwood was persuaded by A. A. Noyes to enroll at Caltech before finishing his high school education ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Organic Chemistry
Physical organic chemistry, a term coined by Louis Hammett in 1940, refers to a discipline of organic chemistry that focuses on the relationship between chemical structures and reactivity, in particular, applying experimental tools of physical chemistry to the study of organic molecules. Specific focal points of study include the rates of organic reactions, the relative chemical stabilities of the starting materials, reactive intermediates, transition states, and products of chemical reactions, and non-covalent aspects of solvation and molecular interactions that influence chemical reactivity. Such studies provide theoretical and practical frameworks to understand how changes in structure in solution or solid-state contexts impact reaction mechanism and rate for each organic reaction of interest. Application Physical organic chemists use theoretical and experimental approaches work to understand these foundational problems in organic chemistry, including classical and statist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the best universities in the world and it is among the most selective in the United States. The university is composed of an undergraduate college and five graduate research divisions, which contain all of the university's graduate programs and interdisciplinary committees. Chicago has eight professional schools: the Law School, the Booth School of Business, the Pritzker School of Medicine, the Crown Family School of Social Work, Policy, and Practice, the Harris School of Public Policy, the Divinity School, the Graham School of Continuing Liberal and Professional Studies, and the Pritzker School of Molecular Engineering. The university has additional campuses and centers in London, Paris, Beijing, Delhi, and Hong Kong, as well as in downtown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties. In Commonwealth English, pharmacists are often called chemists. Chemists use their knowledge to learn the composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry. Materials scientists and metallurgists share much of the same education and skills with chemists. The work of chemists is often related to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
