Dimers (chemistry)

	Dimers (chemistry) Dimer may refer to: * Dimer (chemistry), a chemical structure formed from two similar sub-units Protein dimer, a protein quaternary structure d-dimer * Dimer model, an item in statistical mechanics, based on ''domino tiling'' * Julius Dimer (1871–1945), German chess master See also * Dimery (botany), having two parts in a distinct whorl of a plant structure * Di (other), a prefix * Dymer (other) * -mer, a suffix * Oligomer * Peierls transition A Peierls transition or Peierls distortion is a distortion of the periodic lattice of a one-dimensional crystal. Atomic positions oscillate, so that the perfect order of the 1-D crystal is broken. Peierls’ theorem Peierls' theorem states that ... , sometimes called dimerization {{Disambiguation, surname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Dimer (chemistry) A dimer () ('' di-'', "two" + ''-mer'', "parts") is an oligomer consisting of two monomers joined by bonds that can be either strong or weak, covalent or intermolecular. Dimers also have significant implications in polymer chemistry, inorganic chemistry, and biochemistry. The term ''homodimer'' is used when the two molecules are identical (e.g. A–A) and ''heterodimer'' when they are not (e.g. A–B). The reverse of dimerization is often called dissociation. When two oppositely charged ions associate into dimers, they are referred to as ''Bjerrum pairs'', after Niels Bjerrum. Noncovalent dimers Anhydrous carboxylic acids form dimers by hydrogen bonding of the acidic hydrogen and the carbonyl oxygen. For example, acetic acid forms a dimer in the gas phase, where the monomer units are held together by hydrogen bonds. Under special conditions, most OH-containing molecules form dimers, e.g. the water dimer. Excimers and exciplexes are excited structures with a short lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Protein Dimer In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", '' di-'' + '' -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins. A protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein-coupled cannabinoid receptors have the ability to form both homo- and heterodimers with several ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	D-dimer D-dimer (or D dimer) is a fibrin degradation product (or FDP), a small protein fragment present in the blood after a blood clot is degraded by fibrinolysis. It is so named because it contains two D fragments of the fibrin protein joined by a cross-link, hence forming a protein dimer. D-dimer concentration may be determined by a blood test to help diagnose thrombosis. Since its introduction in the 1990s, it has become an important test performed in people with suspected thrombotic disorders, such as venous thromboembolism. While a negative result practically rules out thrombosis, a positive result can indicate thrombosis, but does not exclude other potential causes. Its main use, therefore, is to exclude thromboembolic disease where the probability is low. D-dimer levels are used as a predictive biomarker for the blood disorder, disseminated intravascular coagulation and in the coagulation disorders associated with COVID-19 infection. A four-fold increase in the protein is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Dimer Model In geometry, a domino tiling of a region in the Euclidean plane is a tessellation of the region by dominoes, shapes formed by the union of two unit squares meeting edge-to-edge. Equivalently, it is a perfect matching in the grid graph formed by placing a vertex at the center of each square of the region and connecting two vertices when they correspond to adjacent squares. Height functions For some classes of tilings on a regular grid in two dimensions, it is possible to define a height function associating an integer to the vertices of the grid. For instance, draw a chessboard, fix a node A_0 with height 0, then for any node there is a path from A_0 to it. On this path define the height of each node A_ (i.e. corners of the squares) to be the height of the previous node A_n plus one if the square on the right of the path from A_n to A_ is black, and minus one otherwise. More details can be found in . Thurston's height condition describes a test for determining whether a simply- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Julius Dimer Julius Dimer (1 August 1871 – 20 October 1945) was a German chess master. At the beginning of his career, he played in several mini tournaments (''Quadrangular'') in Germany; at Altona 1897, Elmshorn 1898, Munich 1900, Kiel 1901, Hamburg 1903, Hamburg 1905, and Bremen 1906. He tied for 7-8th at Eisenach 1896 (the 10th DSB Congress, Robert Henry Barnes won), tied for 7-8th at Amsterdam 1899 (Henry Ernest Atkins won), won at Hamburg/Altona 1906, won at Harburg 1909, and shared 2nd at Barmbek 1911. After World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ..., he took 4th at Hamburg 1921, tied for 5-6th at Kiel 1922, and took 8th at Hamburg 1927. Name Index to Jeremy Gaige's ''Chess Tournament Crosstables'', An Electronic Edition, Anders Thulin, Malmö, 2004-09-01 References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Merosity Merosity (from the greek "méros," which means "having parts") refers to the number of component parts in a distinct whorl of a plant structure. The term is most commonly used in the context of a flower where it refers to the number of sepals in a whorl of the calyx, the number of petals in a whorl of the corolla, the number of stamens in a whorl of the androecium, or the number of carpels in a whorl of the gynoecium. The term may also be used to refer to the number of leaves in a leaf whorl. The adjective ''n''-merous refers to a whorl of ''n'' parts, where ''n'' is any integer greater than one. In nature, five or three parts per whorl have the highest frequency of occurrence, but four or two parts per whorl are not uncommon. Be aware that two consecutive whorls of dimerous petals are often mistaken for tetramerous petals. If all of the whorls in a given floral arrangement have the same merosity, the flower is said to be isomerous, otherwise the flower is anisomerous. For examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Di (other) Di or DI may refer to: Arts and media Music * Di, a tone in the solfège ascending chromatic scale existing between Do and Re * dizi (instrument) or di, a Chinese transverse flute * ''D.I.'' (band), a punk band from Southern California ** ''D.I.'' (EP), a 1983 EP by the same band above Other media * ''The D.I.'', 1957 military film by Jack Webb * '' Dagens Industri'', a Swedish financial newspaper * DI.FM, an internet radio service Businesses and organisations * Defence Intelligence, a UK military intelligence agency * Defensa Interior, an anti-Franco militant anarchist group in 1960s Spain * Deseret Industries, an LDS thrift store * Desert Inn, a former casino in Las Vegas * Direction Italy, a liberal-conservative political party in Italy * Dirgantara Indonesia, an Indonesian aircraft company * Discovery Institute, an intelligent design advocacy group * Norwegian Air UK, a UK based airline (IATA designator) * DynCorp International, a major United States defense contra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Dymer (other) Dymer may refer to: * Dymer, Poland * Dymer, Kyiv Oblast Dymer ( uk, Димер, russian: Ды́мер) is an urban-type settlement in Vyshhorod Raion of Kyiv Oblast (province) of Ukraine with a population of It hosts the administration of Dymer settlement hromada, one of the hromadas of Ukraine. Clas ..., Ukraine * ''Dymer'' (poem), by C. S. Lewis See also * Dimer (other) {{disambig, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	-mer {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Oligomer In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of units derived, actually or conceptually, from molecules of lower relative molecular mass.'' The name is composed of Greek elements '' oligo-'', "a few" and '' -mer'', "parts". An adjective form is ''oligomeric''. The oligomer concept is contrasted to that of a polymer, which is usually understood to have a large number of units, possibly thousands or millions. However, there is no sharp distinction between these two concepts. One proposed criterion is whether the molecule's properties vary significantly with the removal of one or a few of the units. An oligomer with a specific number of units is referred to by the Greek prefix denoting that number, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]