A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions. The neutron-fission chain reaction: a neutron plus a fissionable atom causes a fission resulting in a larger number of neutrons than was consumed in the initial reaction. Chemical reactions, where a product of a reaction is itself a reactive particle which can cause more similar reactions. For example, every step of H2 + Cl2 chain reaction consumes one molecule of H

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See also:

Proton-proton chain reaction, Proton-proton chain reaction - The pp chain reaction, Proton-proton chain reaction - The pp I branch, Proton-proton chain reaction - The pp II branch, Proton-proton chain reaction - The pp III branch, Proton-proton chain reaction - The pp IV or Hep, Proton-proton chain reaction - Energy release, Proton-proton chain reaction - The pep reaction

Read more here: » Proton-proton chain reaction: Encyclopedia II - Proton-proton chain reaction - The pp chain reaction

PCR was invented by Kary Mullis while working for Cetus in December 1983. He was awarded the Nobel Prize in Chemistry in 1993 for this achievement, only seven years after his colleagues at Cetus first reduced his proposal to practice. Mullis's idea was to develop a process by which DNA could be artificially multiplied through repeated cycles of duplication driven by an enzyme called DNA polymerase. DNA polymerase occurs naturally in living organisms, where it functions to duplicate DNA when cells divide in mitosis and meiosis. Polymer ...

See also:

Polymerase chain reaction, Polymerase chain reaction - PCR in practice, Polymerase chain reaction - Primers, Polymerase chain reaction - Procedure, Polymerase chain reaction - Example, Polymerase chain reaction - PCR optimization, Polymerase chain reaction - PCR Difficulties, Polymerase chain reaction - Practical modifications to the PCR technique, Polymerase chain reaction - Recent developments in PCR techniques, Polymerase chain reaction - Uses of PCR, Polymerase chain reaction - Genetic fingerprinting, Polymerase chain reaction - Paternity testing, Polymerase chain reaction - Detection of hereditary diseases, Polymerase chain reaction - Cloning genes, Polymerase chain reaction - Mutagenesis, Polymerase chain reaction - Analysis of ancient DNA, Polymerase chain reaction - Genotyping of specific mutations, Polymerase chain reaction - Comparison of gene expression, Polymerase chain reaction - History, Polymerase chain reaction - Patent wars

Read more here: » Polymerase chain reaction: Encyclopedia II - Polymerase chain reaction - History

Karma yoga is the yoga of action or work; specifically, karma yoga is the path of dedicated work: renouncing the results of our actions as a spiritual offering rather than hoarding the results for ourselves.

Karma is both action and the result of action. What we experience today is the result of our karma--both good and bad--created by our previous actions. This chain of cause and effect that we ourselves have created can be snapped by karma yoga: fighting fire with fire, we use the sword of karma yoga to stop the chain reaction of cause and effect.

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The critical mass of fissile material is the amount needed for a sustained nuclear chain reaction. The critical mass of a fissionable material depends upon the nuclear (e.g. the nuclear fission cross-section) and physical properties of the material (in particularly the density), its geometry (shape), and its purity, as well as whether it is surrounded by a neutron reflector or interrupted by an absorber. See also neutron radiation. An assembly in which a chain reaction is just possible is called critical, and is said to ...

Including:

• Critical mass - Critical mass of a sphere
• Critical mass - Weapon design
• Critical mass - Criticality pathways tutorial

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An alkane in organic chemistry is a saturated hydrocarbon without cycles, that is, an acyclic hydrocarbon in which the molecule has the maximum possible number of hydrogen atoms and so has no double bonds. Alkanes are also often known as paraffins, or collectively as the paraffin series; these terms, however, are also used to apply only to alkanes whose carbon atoms form a single, unbranched chain; when this is done, branched-chain alkanes are called isoparaffins. Alkanes are aliphatic compounds. The general formu ...

Including:

• Alkane - Isomerism
• Alkane - Nomenclature of alkanes
• Alkane - Alkanes with unbranched carbon chains
• Alkane - Alkanes with branched carbon chains
• Alkane - Trivial names
• Alkane - Occurrence
• Alkane - Purification and use
• Alkane - Preparation
• Alkane - Molecular geometry
• Alkane - Bond lengths and bond angles
• Alkane - Conformation
• Alkane - Properties
• Alkane - Physical properties
• Alkane - Chemical properties
• Alkane - Thermochemistry
• Alkane - Spectroscopic properties
• Alkane - Reactions
• Alkane - Reactions with oxygen
• Alkane - Reactions with halogens
• Alkane - Cracking and reforming
• Alkane - Other reactions
• Alkane - Hazards
• Alkane - Alkanes in nature
• Alkane - Bacteria and archaea
• Alkane - Fungi and plants
• Alkane - Animals
• Alkane - Ecological relations

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In physics, nuclear fusion is the process by which two nuclei join together to form a heavier nucleus. It is accompanied by the release or absorption of energy depending on the masses of the nuclei involved. Iron and nickel nuclei have the largest binding energies of all nuclei and therefore are the most stable. The fusion of two nuclei to produce a nucleus lighter than iron or nickel generally gives off energy while t ...

Including:

• Nuclear fusion - Requirements for fusion
• Nuclear fusion - Methods of fuel confinement
• Nuclear fusion - Important fusion reactions
• Nuclear fusion - Astrophysical reaction chains
• Nuclear fusion - Criteria and candidates for terrestrial reactions
• Nuclear fusion - Neutronicity confinement requirement and power density
• Nuclear fusion - Bremsstrahlung losses

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A reaction is the following: In physics, a reaction is defined by Newton's third law: "For every action there is an equal and opposite reaction". The idea that any given force has a pair or opposite force. Usually, a reaction is any response caused by some other action. Chemical reaction Reflex reaction light reaction Hill reaction Chain reaction In politics, the reaction is the attitude of the reactionaries, or thei

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A DNA polymerase is an enzyme that assists in DNA replication. Such enzymes catalyze the polymerization of deoxyribonucleotides alongside a DNA strand, which they "read" and use as a template. The newly polymerized molecule is complementary to the template strand and identical to the template's partner strand. All DNA polymerases synthesize DNA in the 5' to 3' direction. No known DNA polymerase is able to begin a new chain (de novo). They can only add a nucleotide onto a preexisting 3'- OH group. For this reason DNA poly ...

Including:

• DNA polymerase - Bacteria
• DNA polymerase - Eukaryotes

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Uranium-235 is an isotope of uranium that differs from the element's other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction, i.e., it is fissile. In fact, U-235 is the only fissile isotope found in nature. It was discovered in 1935 by Arthur Jeffrey Dempster. A uranium nucleus that absorbs a neutron splits into two lighter nuclei; this is called nuclear fission. It releases either two or three neutrons which continue the reaction. In nuclear reactors, the reaction is slowed down by the ad ...

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The CNO (carbon-nitrogen-oxygen) cycle is one of two fusion reactions by which stars convert hydrogen to helium, the other being the proton-proton chain. While the proton-proton chain is more important in stars the size of the sun or less, theoretical models show that the CNO cycle is the dominant source of energy in heavier stars. The CNO process was proposed in 1938 by Hans Bethe. The reactions of the CNO cycle are: 12C + 1H → 13N + ...

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Inorganic chemistry is the branch of chemistry concerned with the properties and reactions of inorganic compounds. This includes all chemical compounds except the many which are based upon chains or rings of carbon atoms, which are termed organic compounds and are studied under the separate heading of organic chemistry. The distinction between the two disciplines is not absolute and there is much overlap, most impo ...

Including:

• Inorganic chemistry - Categories of inorganic chemical reactions
• Inorganic chemistry - Branches of inorganic chemistry

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Vedanā (Pāli word) meaning feeling or sensation.One of the five aggregates (khandha). Described by the Buddha as having both mental and physical aspects; therefore vedanā offers a means to examine the totality of the mental-physical phenomenon. In the Chain of Conditioned Arising (paţicca samuppada), the Buddha explained that tanhā, the cause of suffering, arises as a reaction to vedanā. By learning to observe vedanā objectively one can avoid any new reactions, and can experience directly within oneself the reality of impermanence (anicca). This experience is essential for the development of d ...

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Uracil is one of the four RNA nucleobases, replacing thymine as found in DNA. Just like thymine, uracil can form a base pair with adenine via two hydrogen bonds, but it lacks the methyl group present in thymine. Uracil, in comparison to thymine, will more readily degenerate into cytosine. Uracil is only very rarely observed in DNA. Incorporation of uracil coupled with the enzyme, uracil N glycosilase (Ung) in polymerase chain reactions (PCR) is used as a method of cross-over contamination prevent

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On December 2, 1942, the world's first self-sustaining nuclear chain reaction took place in the world's first nuclear reactor, Chicago Pile-1, shortened as CP-1, built on a racquets court under the abandoned west stands of the Alonzo Stagg Field stadium on the University of Chicago campus. Operation of CP-1 was terminated in February 1943 and the nuclear reactor dismantled and moved to the laboratory's Palos Park site A. It was reconstructed using CP-1 materials but enlarged with a radiation shi ...

Including:

• Chicago Pile-1 - Illustrations external site

Read more here: » Chicago Pile-1: Encyclopedia - Chicago Pile-1

Asparagine is one of the 20 most common natural amino acids on Earth. It has carboxamide as the side chain's functional group. It is considered a non-essential amino acid. Its three-letter abbreviation is Asn, and its one-letter abbreviation is N. A three-letter designation for either asparagine or aspartic acid is Asx (one-letter abbreviation: B). A reaction between asparagine and reducing sugars or reactive carbonyls produces acrylam ...

Including:

• Asparagine - Biosynthesis
• Asparagine - Degradation

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The enzyme cytochrome c oxidase (PDB 2OCC, EC 1.9.3.1) is a large transmembrane protein found in the mitochondrion and is the terminal electron acceptor in the electron transfer chain, taking 4 reducing equivalents from cytochrome c and converting molecular oxygen to water. In the process, it translocates protons, helping to establish a chemiosmotic potential that the ATP synthase then uses to synthesize ATP. Summary reaction: 4 Fe+2-cytochrome c + 4H+ + O2Including:

• Cytochrome c oxidase - External link

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A criticality accident (also sometimes referred to as an "excursion" or "power excursion") occurs when a nuclear chain reaction is accidentally allowed to occur in fissile material, such as enriched uranium or plutonium. This releases neutron radiation which is highly dangerous to surrounding personnel and which causes induced radioactivity in the surroundings. When such incidents occur outside reactor cores and test facilities where fission is intended to occur, they pose a high risk both of injury or death to su ...

Including:

• Criticality accident - Cause
• Criticality accident - Description
• Criticality accident - Confusion with Cherenkov radiation and other effects
• Criticality accident - Records

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Suppose a fission caused by a neutron hitting a nucleus produces 3 neutrons (i.e. 2 extra). Also suppose k > 1. The probability that a neutron causes a fission is k / 3. The probability that a free neutron does not cause a chain reaction is (1 - k / 3) (no fission at all) plus the probability of at least one fission, while none of the 3 neutrons produced causes a chain reaction. The latter has a probability of k / 3 times the cube of the first-mentioned probability that a free neutron does not cause a chain reaction. ...

See also:

Nuclear chain reaction, Nuclear chain reaction - Numerical example for the probability of a chain reaction, Nuclear chain reaction - Predetonation

Read more here: » Nuclear chain reaction: Encyclopedia II - Nuclear chain reaction - Numerical example for the probability of a chain reaction

The so-called pep (proton-electron-proton) reaction is a pretty rare one, that can take place instead of the pp reaction: 1H + e− + 1H → 2H + νe In the Sun, the frequency of pep reaction versus pp reaction is 1:400. However the neutrinos released are far more energetic: while neutrinos produced in the first step of the pp reaction range in energy up to 0.42 MeV, the neutrinos from ...

See also:

Proton-proton chain reaction, Proton-proton chain reaction - The pp chain reaction, Proton-proton chain reaction - The pp I branch, Proton-proton chain reaction - The pp II branch, Proton-proton chain reaction - The pp III branch, Proton-proton chain reaction - The pp IV or Hep, Proton-proton chain reaction - Energy release, Proton-proton chain reaction - The pep reaction

Read more here: » Proton-proton chain reaction: Encyclopedia II - Proton-proton chain reaction - The pep reaction