Viscount Ilya Romanovich Prigogine was a Belgian physical chemist of Russian-Jewish origin, noted for his work on dissipative structures, complex systems, and irreversibility.
KPP may refer to:
Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is different from chemical thermodynamics, which deals with the direction in which a reaction occurs but in itself tells nothing about its rate. Chemical kinetics includes investigations of how experimental conditions influence the speed of a chemical reaction and yield information about the reaction's mechanism and transition states, as well as the construction of mathematical models that also can describe the characteristics of a chemical reaction.
A hydrogen ion is created when a hydrogen atom loses an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. Due to its extremely high charge density of approximately 2×1010 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it readily hydrates, i.e., bonds quickly. The hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions.
Atmospheric chemistry is a branch of atmospheric science in which the chemistry of the Earth's atmosphere and that of other planets is studied. It is a multidisciplinary approach of research and draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology and other disciplines. Research is increasingly connected with other areas of study such as climatology.
CHEMKIN is a proprietary software tool for solving complex chemical kinetics problems. It is used worldwide in the combustion, chemical processing, microelectronics and automotive industries, and also in atmospheric science. It was originally developed at Sandia National Laboratories and is now developed by a US company, Reaction Design.
Desorption is the physical process where adsorbed atoms or molecules are released from a surface into the surrounding vacuum or fluid. This occurs when a molecule gains enough energy to overcome the activation barrier and the binding energy that keep it attached to the surface.
In organic chemistry, cheletropic reactions, also known as chelotropic reactions, are a type of pericyclic reaction. Specifically, cheletropic reactions are a subclass of cycloadditions. The key distinguishing feature of cheletropic reactions is that on one of the reagents, both new bonds are being made to the same atom.
SIESTA is an original method and its computer program implementation, to efficiently perform electronic structure calculations and ab initio molecular dynamics simulations of molecules and solids. SIESTA uses strictly localized basis sets and the implementation of linear-scaling algorithms. Accuracy and speed can be set in a wide range, from quick exploratory calculations to highly accurate simulations matching the quality of other approaches, such as the plane-wave and all-electron methods.
In organic chemistry, the Hammett equation describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant. This equation was developed and published by Louis Plack Hammett in 1937 as a follow-up to qualitative observations in his 1935 publication.
AutoChem is NASA release software that constitutes an automatic computer code generator and documenter for chemically reactive systems written by David Lary between 1993 and the present. It was designed primarily for modeling atmospheric chemistry, and in particular, for chemical data assimilation.
William Wallace Cleland (January 6, 1930 – March 6, 2013, often cited as W. W. Cleland, and known almost universally as "Mo Cleland", was a University of Wisconsin-Madison biochemistry professor. His research was concerned with enzyme reaction mechanism and enzyme kinetics, especially multiple-substrate enzymes. He was elected to the National Academy of Sciences in 1985.
In the field of computational chemistry, energy minimization is the process of finding an arrangement in space of a collection of atoms where, according to some computational model of chemical bonding, the net inter-atomic force on each atom is acceptably close to zero and the position on the potential energy surface (PES) is a stationary point. The collection of atoms might be a single molecule, an ion, a condensed phase, a transition state or even a collection of any of these. The computational model of chemical bonding might, for example, be quantum mechanics.
A chemical transport model (CTM) is a type of computer numerical model which typically simulates atmospheric chemistry and may give air pollution forecasting.
Cantera is an open-source chemical kinetics software used for solving chemically reacting laminar flows. It has been used as a third-party library in external reacting flow simulation codes, such as FUEGO and CADS, using Fortran, C++, etc. to evaluate properties and chemical source terms that appear in the application's governing equations. Cantera was originally written and developed by Prof. Dave Goodwin of California Institute of Technology. It is written in C++ and can be used from C++, Python, Matlab and Fortran.
Chemical WorkBench is a proprietary simulation software tool aimed at the reactor scale kinetic modeling of homogeneous gas-phase and heterogeneous processes and kinetic mechanism development. It can be effectively used for the modeling, optimization, and design of a wide range of industrially and environmentally important chemistry-loaded processes. Chemical WorkBench is a modeling environment based on advanced scientific approaches, complementary databases, and accurate solution methods. Chemical WorkBench is developed and distributed by Kintech Lab.
Reaction Design is a San Diego-based developer of combustion simulation software used by engineers to design cleaner burning and fuel-efficient combustors and engines, found in everything from automobiles to turbines for power generation and aircraft propulsion to large diesel engines that use pistons the size of rooms to propel ships locomotives. The technology is also used to model spray vaporization in electronic materials processing applications and predict mixing reactions in chemical plants. Ansys, a leader in engineering simulation software, acquired Reaction Design in January 2014.
In chemistry, reaction progress kinetic analysis (RPKA) is a subset of a broad range of kinetic techniques utilized to determine the rate laws of chemical reactions and to aid in elucidation of reaction mechanisms. While the concepts guiding reaction progress kinetic analysis are not new, the process was formalized by Professor Donna Blackmond in the late 1990s and has since seen increasingly widespread use. Unlike more common pseudo-first-order analysis, in which an overwhelming excess of one or more reagents is used relative to a species of interest, RPKA probes reactions at synthetically relevant conditions Generally, this analysis involves a system in which the concentrations of multiple reactants are changing measurably over the course of the reaction. As the mechanism can vary depending on the relative and absolute concentrations of the species involved, this approach obtains results that are much more representative of reaction behavior under commonly utilized conditions than do traditional tactics. Furthermore, information obtained by observation of the reaction over time may provide insight regarding unexpected behavior such as induction periods, catalyst deactivation, or changes in mechanism.