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Topological insulator MBE is performed in high vacuum or ultra-high vacuum, the elements are heated in different electron beam evaporators until they sublime. The gaseous elements then condense on the wafer where they react with each other to form single crystals. MBE is an appropriate technique for the growth of high quality single-crystal films. In order to avoid a huge lattice mismatch and defects at the interface, the substrate and thin film are expected to have similar lattice constants. MBE has an advantage over other methods due to the fact that the synthesis is performed in high vacuum hence resulting in less contamination. Additionally, lattice defect is reduced due to the ability to influence the growth rate and the ratio of species of source materials present at the substrate interface. Furthermore, in MBE, samples can be grown layer by layer which results in flat surfaces with smooth interface for engineered heterostructures. Moreover, MBE synthesis technique benefits from the ease of moving a topological insulator sample from the growth chamber to a characterization chamber such as angle-resolved photoemission spectroscopy (ARPES) or scanning tunneling microscopy (STM) studies. Due to the weak Van der Waals bonding, which relaxes the lattice-matching condition, TI can be grown on a wide variety of substrates such as Si(111), AlO , GaAs(111), InP(111), CdS(0001) and YFeO | https://en.wikipedia.org/wiki?curid=23649871 |
Topological insulator Thus far, the field of topological insulators has been focused on bismuth and antimony chalcogenide based materials such as BiSe , BiTe , SbTe or BiSb, BiSbTeS. The choice of chalcogenides is related to the Van der Waals relaxation of the lattice matching strength which restricts the number of materials and substrates. Bismuth chalcogenides have been studied extensively for TIs and their applications in thermoelectric materials. The Van der Waals interaction in TIs exhibit important features due to low surface energy. For instance, the surface of BiTe is usually terminated by Te due to its low surface energy. Bismuth chalcogenides have been successfully grown on different substrates. In particular, Si has been a good substrate for the successful growth of BiTe . However, the use of sapphire as substrate has not been so encouraging due to a large mismatch of about 15%. The selection of appropriate substrate can improve the overall properties of TI. The use of buffer layer can reduce the lattice match hence improving the electrical properties of TI. BiSe can be grown on top of various BiInSe buffers. Table 1 shows BiSe , BiTe , SbTe on different substrates and the resulting lattice mismatch. Generally, regardless of the substrate used, the resulting films have a textured surface that is characterized by pyramidal single-crystal domains with quintuple-layer steps | https://en.wikipedia.org/wiki?curid=23649871 |
Topological insulator The size and relative proportion of these pyramidal domains vary with factors that include film thickness, lattice mismatch with the substrate and interfacial chemistry-dependent film nucleation. The synthesis of thin films have the stoichiometry problem due to the high vapor pressures of the elements. Thus, binary tetradymites are extrinsically doped as n-type (BiSe , BiTe ) or p-type (SbTe ). Due to the weak van der Waals bonding, graphene is one of the preferred substrates for TI growth despite the large lattice mismatch. The first step of topological insulators identification takes place right after synthesis, meaning without breaking the vacuum and moving the sample to an atmosphere. That could be done by using angle-resolved photoemission spectroscopy (ARPES) or scanning tunneling microscopy (STM) techniques. Further measurements includes structural and chemical probes such as X-ray diffraction and energy-dispersive spectroscopy but depending on the sample quality, the lack of sensitivity could remain. Transport measurements cannot uniquely pinpoint the Z2 topology by definition of the state. The field of topological insulators still needs to be developed. The best bismuth chalcogenide topological insulators have about 10 meV bandgap variation due to the charge. Further development should focus on the examination of both: the presence of high-symmetry electronic bands and simply synthesized materials. One of the candidates is half-Heusler compounds | https://en.wikipedia.org/wiki?curid=23649871 |
Topological insulator These crystal structures can consist of a large number of elements. Band structures and energy gaps are very sensitive to the valence configuration; because of the increased likelihood of intersite exchange and disorder, they are also very sensitive to specific crystalline configurations. A nontrivial band structure that exhibits band ordering analogous to that of the known 2D and 3D TI materials was predicted in a variety of 18-electron half-Heusler compounds using first-principles calculations. These materials have not yet shown any sign of intrinsic topological insulator behavior in actual experiments. | https://en.wikipedia.org/wiki?curid=23649871 |
Gold chalcogenides are compounds formed between gold and one of the chalcogens, elements from group 16 of the periodic table: oxygen, sulfur, selenium, or tellurium. Natural gold tellurides, like calaverite and krennerite (AuTe), petzite ( AgAuTe), and sylvanite (AgAuTe), are minor ores of gold (and tellurium). See telluride minerals for more information on individual naturally occurring tellurides. | https://en.wikipedia.org/wiki?curid=23650053 |
Society of Glass Technology The (SGT) is an organization for individuals and organizations with a professional interest in glass manufacture and usage. The Society is based in the United Kingdom, with its offices in Sheffield, South Yorkshire, England, but it has a worldwide membership. The objects of the Society "are to encourage and advance the study of the history, art, science, design, manufacture, after treatment, distribution and end use of glass of any and every kind". The Society was founded by W E S Turner in 1916. The Society is a founder member of the International Commission on Glass and the European Society of Glass Science and Technology. The publication of scientific and technical works is a major activity of the Society, and currently it publishes two journals. These were formed in 2006 when the journals of the and the Deutsche Glastechnische Gesellschaft were combined to form the "European Journal of Glass Science and Technology". From 1960 this was split into two journals: | https://en.wikipedia.org/wiki?curid=23650426 |
C8H7NO The molecular formula CHNO (molar mass: 133.14728 g/mol, exact mass: 133.052764) may refer to: | https://en.wikipedia.org/wiki?curid=23652048 |
C11H15NO2 The molecular formula CHNO (molar mass : 193.24 g/mol, exact mass : 193.110279) may refer to: | https://en.wikipedia.org/wiki?curid=23652115 |
C10H11ClO3 The molecular formula CHClO (molar mass: 214.64 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23652153 |
C8H16O4 The molecular formula CHO (molar mass: 176.21 g/mol, exact mass: 176.104859) may refer to: | https://en.wikipedia.org/wiki?curid=23652669 |
C8H8O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23652872 |
C5H5NO2 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23653043 |
C15H25NO3 The molecular formula CHNO (molar mass : 267.36 g/mol, exact mass : 267.183444) may refer to: | https://en.wikipedia.org/wiki?curid=23653409 |
C17H20N2O The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23653447 |
C7H14NO5P The molecular formula CHNOP (molar mass: 223.16 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23653488 |
Recrystallization (geology) In geology, solid-state recrystallization is a metamorphic process that occurs under temperature and pressure where atoms of a mineral are reorganized by diffusion and/or dislocation glide. The mineral composition may remain unchanged. This process can be illustrated by observing how snow recrystallizes to ice. As opposed to metasomatism, which is a change in composition, recrystallization can be a purely physical process. Limestone is a sedimentary rock that undergoes metamorphic recrystallization to form marble, and clays can recrystallize to muscovite mica. | https://en.wikipedia.org/wiki?curid=23658144 |
C10H6O2 CHO can refer to: | https://en.wikipedia.org/wiki?curid=23661478 |
C10H9N CHN (molar mass : 143.19 g/mol) may refer to : | https://en.wikipedia.org/wiki?curid=23661497 |
C23H46N6O13 The molecular formula CHNO (molar mass: 614.64 g/mol, exact mass: 614.312286) may refer to: | https://en.wikipedia.org/wiki?curid=23661513 |
C10H14N2 The molecular formula CHN may refer to: | https://en.wikipedia.org/wiki?curid=23661539 |
C8H11NO3 The molecular formula CHNO (molar mass: 169.17 g/mol, exact mass: 169.073893) may refer to | https://en.wikipedia.org/wiki?curid=23662088 |
C7H12 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23662851 |
C8H16O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23662911 |
C18H34O2 The molecular formula CHO (molar mass : 282.46 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23662943 |
C21H32O3 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23663191 |
Ferrocenium tetrafluoroborate is an organometallic compound with the formula [Fe(CH)]BF. This salt is composed of the cation [Fe(CH)] and the tetrafluoroborate anion (). The related hexafluorophosphate is also a popular reagent with similar properties. The cation is often abbreviated Fc or CpFe. The salt is deep blue in color and paramagnetic. Ferrocenium salts are sometimes used as one-electron oxidizing agents, and the reduced product, ferrocene, is inert and readily separated from ionic products. The ferrocene–ferrocenium couple is often used as a reference in electrochemistry. The standard potential of ferrocene-ferrocenium is 0.400 V vs. the normal hydrogen electrode (NHE) and is often assumed to be invariant between different solvents. Commercially available, this compound may be prepared by oxidizing ferrocene typically with ferric salts followed by addition of fluoroboric acid. A variety of other oxidants work well also, such as nitrosyl tetrafluoroborate. Many analogous ferrocenium salts are known. | https://en.wikipedia.org/wiki?curid=23664837 |
Manganese acetate can refer to: | https://en.wikipedia.org/wiki?curid=23666084 |
Mercury(I) nitrate is a chemical compound with the formula Hg(NO). It is used in the preparation of other mercury(I) compounds, and is toxic. is formed when elemental mercury is combined with "dilute" nitric acid (concentrated nitric acid will yield mercury(II) nitrate). is a reducing agent which is oxidized upon contact with air. Mercuric nitrate can be reacted with elemental mercury to form mercurous nitrate. Solutions of mercury(I) nitrate are acidic due to slow reaction with water: Hg(NO)(OH) forms a yellow precipitate. If the solution is boiled or exposed to light, mercury(I) nitrate undergoes a disproportionation reaction yielding elemental mercury and mercury(II) nitrate: These reactions are reversible; the nitric acid formed can redissolve the basic salt. | https://en.wikipedia.org/wiki?curid=23666867 |
List of medicine contamination incidents The following list encompasses notable medicine contamination and adulteration incidents. | https://en.wikipedia.org/wiki?curid=23667138 |
AJ alloys (AJ52 and AJ62) are die castable alloys of magnesium that have good creep resistance at high temperature. They contain magnesium, aluminum, and strontium. In the names the 'J' refers to Strontium. AJ52 has higher creep resistance, and AJ62 has better castability. Both are used in the BMW magnesium–aluminum composite engine block. | https://en.wikipedia.org/wiki?curid=23670922 |
Homogeneous and heterogeneous mixtures A homogeneous mixture is a solid, liquid, or gaseous mixture that has the same proportions of its components throughout any given sample. Conversely, a heterogeneous mixture has components in which proportions vary throughout the sample. "Homogeneous" and "heterogeneous" are not absolute terms, but are dependent on context and the size of the sample. In chemistry, if the volume of a homogeneous suspension is divided in half, the same amount of material is suspended in both halves of the substance. An example of a homogeneous mixture is air. In physical chemistry and materials science this refers to substances and mixtures which are in a single phase. This is in contrast to a substance that is heterogeneous. A solution is a special type of homogeneous mixture where the ratio of solute to solvent remains the same throughout the solution and the particles are not visible with the naked eye, even if homogenized with multiple sources. In solutions, solutes will not settle out after any period of time and they can't be removed by physical methods, such as a filter or centrifuge. As a homogeneous mixture, a solution has one phase (solid, liquid, or gas), although the phase of the solute and solvent may initially have been different (e.g., salt water). Air can be more specifically described as a gaseous solution (oxygen and other gases dissolved in the major component, nitrogen). Since interactions between molecules play almost no role, dilute gases form trivial solutions | https://en.wikipedia.org/wiki?curid=23672776 |
Homogeneous and heterogeneous mixtures In part of the literature, they are not even classified as solutions. In gas, intermolecular space is the greatest—and intermolecular force of attraction is least. Some examples can be oxygen, hydrogen, or nitrogen. In chemistry, a mixture is a substance containing two or more elements or compounds that are not covalently bound to each other and retain their own chemical and physical identities—a substance which has two or more constituent physical substances. Mixtures, in the broader sense, are two or more substances physically in the same place, but these are not chemically combined, therefore ratios are not necessarily considered. Solid homogeneous mixtures, like gaseous and liquid homogeneous mixtures, contain different elements mixed uniformly and cannot be separated easily. An example of a solid homogeneous mixture is bronze, which is a mixture of copper and tin. Homogeneous mixtures have the same proportions of the various components throughout a given sample (or multiple samples of different proportion), creating a consistent mixture. However, two homogeneous mixtures of the same pair of substances may differ widely from each other and can be homogenized to make a constant. Homogeneous mixtures always have the same composition. Mixtures can be characterized by being separable by mechanical means e.g. heat, filtration, gravitational sorting, centrifugation etc. During the sampling of heterogeneous mixtures of particles, the variance of the sampling error is generally non-zero | https://en.wikipedia.org/wiki?curid=23672776 |
Homogeneous and heterogeneous mixtures Gy's sampling theory quantitatively defines the heterogeneity of a particle as: where | https://en.wikipedia.org/wiki?curid=23672776 |
RDF-Powerstation The RDF-PowerStation is a peripheral thermal recovery plant, which is based on renewable energy (especially on Refuse derived fuel (RDF)). The is directly integrated in a building like a business centre and is used as a cogeneration or trigeneration plant. Due to that the incineration unit and all additional components, which are necessary for the operation of the plant and the utilization of the energy, are located in the consumers’ area. So the energy is produced and used at the same place. The technical realization of this concept is based on the configuration of the process diagram. Before the crude materials (e.g. municipal or commercial waste) are introduced into the incineration unit, these resources are mechanically treated at an external station. The treatment intensity is significantly linked to the quality and composition of the primary material. So the treatment process can be very different – from an ordinary crushing and a rough sortation to a multistep milling process with various product streams and a finishing briquetting. The final product of this step – the Refuse derived fuel – is used in the “RDF- Powerstation”. The combustion unit is equipped with a water-cooled reciprocating grate, a post- combustion chamber, where the selective non-catalytic reduction of the nitrogen oxides is included and a steam boiler with the heat exchangers. The main part of the heat energy, which is captured in the live steam, is used for the electricity production | https://en.wikipedia.org/wiki?curid=23674090 |
RDF-Powerstation Another portion is applied for a heating grid or an absorption refrigerator. Following the steam boiler the flue gas enters the 4-stage dry scrubber. There the pollutants of the flue gas are extracted by different additives, which separated at the baghouse filters. Additionally a catalyzer is included to enable an extra stage for the removal of the nitrogen oxides (SCR- process). At the end of flue gas purification process an algae reactor is mounted, where algae is converting carbon dioxide to biomass. | https://en.wikipedia.org/wiki?curid=23674090 |
Recrystallization (chemistry) In chemistry, recrystallization is a technique used to purify chemicals. By dissolving both impurities and a compound in an appropriate solvent, either the desired compound or impurities can be removed from the solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, "recrystallization" can refer to the natural growth of larger ice crystals at the expense of smaller ones. In chemistry, recrystallization is a procedure for purifying compounds. The most typical situation is that a desired "compound A" is contaminated by a small amount of "impurity B". There are various methods of purification that may be attempted (see Separation process), recrystallization being one of them. There are also different recrystallization techniques that can be used such as: Typically, the mixture of "compound A" and "impurity B" is dissolved in the smallest amount of hot solvent to fully dissolve the mixture, thus making a saturated solution. The solution is then allowed to cool. As the solution cools the solubility of compounds in solution drops. This results in the desired compound dropping (recrystallizing) from solution. The slower the rate of cooling, the bigger the crystals form. In an ideal situation the solubility product of the impurity, B, is not exceeded at any temperature. In that case the solid crystals will consist of pure A and all the impurity will remain in solution. The solid crystals are collected by filtration and the filtrate is discarded | https://en.wikipedia.org/wiki?curid=23681458 |
Recrystallization (chemistry) If the solubility product of the impurity is exceeded, some of the impurity will co-precipitate. However, because of the relatively low concentration of the impurity, its concentration in the precipitated crystals will be less than its concentration in the original solid. Repeated recrystallization will result in an even purer crystalline precipitate. The purity is checked after each recrystallization by measuring the melting point, since impurities lower the melting point. NMR spectroscopy can also be used to check the level of impurity. Repeated recrystallization results in some loss of material because of the non-zero solubility of compound A. The crystallization process requires an initiation step, such as the addition of a "seed" crystal. In the laboratory a minuscule fragment of glass, produced by scratching the side of the glass recrystallization vessel, may provide the nucleus on which crystals may grow. Successful recrystallization depends on finding the right solvent. This is usually a combination of prediction/experience and trial/error. The compounds must be more soluble at the higher temperature than at the lower temperatures. Any insoluble impurity is removed by the technique of hot filtration. This method is the same as the above but where two (or more) solvents are used. This relies on both "compound A" and "impurity B" being soluble in a first solvent. A second solvent is slowly added | https://en.wikipedia.org/wiki?curid=23681458 |
Recrystallization (chemistry) Either "compound A" or "impurity B" will be insoluble in this solvent and precipitate, whilst the other of "compound A"/"impurity B" will remain in solution. Thus the proportion of first and second solvents is critical. Typically the second solvent is added slowly until one of the compounds begins to crystallize from solution and then the solution is cooled. Heating is not required for this technique but can be used. The reverse of this method can be used where a mixture of solvent dissolves both A and B. One of the solvents is then removed by distillation or by an applied vacuum. This results in a change in the proportions of solvent causing either "compound A" or "impurity B" to precipitate. Hot filtration can be used to separate "compound A" from both "impurity B" and some "insoluble matter C". This technique normally uses a single-solvent system as described above. When both "compound A" and "impurity B" are dissolved in the minimum amount of hot solvent, the solution is filtered to remove "insoluble matter C". This matter may be anything from a third impurity compound to fragments of broken glass. For a successful procedure, one must ensure that the filtration apparatus is hot in order to stop the dissolved compounds crystallizing from solution during filtration, thus forming crystals on the filter paper or funnel. One way to achieve this is to heat a conical flask containing a small amount of clean solvent on a hot plate. A filter funnel is rested on the mouth, and hot solvent vapors keep the stem warm | https://en.wikipedia.org/wiki?curid=23681458 |
Recrystallization (chemistry) Jacketed filter funnels may also be used. The filter paper is preferably fluted, rather than folded into a quarter; this allows quicker filtration, thus less opportunity for the desired compound to cool and crystallize from the solution. Often it is simpler to do the filtration and recrystallization as two independent and separate steps. That is dissolve "compound A" and "impurity B" in a suitable solvent at room temperature, filter (to remove insoluble compound/glass), remove the solvent and then recrystallize using any of the methods listed above. Crystallization requires an initiation step. This can be spontaneous or can be done by adding a small amount of the pure compound (a seed crystal) to the saturated solution, or can be done by simply scratching the glass surface to create a seeding surface for crystal growth. It is thought that even dust particles can act as simple seeds. Growing crystals for X-ray crystallography can be quite difficult. For X-ray analysis, single perfect crystals are required. Typically a small amount (5–100 mg) of pure compound is used, and crystals are allowed to grow very slowly. Several techniques can be used to grow these perfect crystals: For ice, recrystallization refers to the growth of larger crystals at the expense of smaller ones. Some biological antifreeze proteins have been shown to inhibit this process, and the effect may be relevant in freezing-tolerant organisms. | https://en.wikipedia.org/wiki?curid=23681458 |
Heino Finkelmann (born 1945, Gronau) is a retired German organic chemist in the area of liquid-crystalline elastomers. After earning an engineering degree, Finkelmann graduated 1972 as chemist (Diplom) from Technical University of Berlin. 1975 he earned his PhD at the Paderborn University under the supervision of Horst Stegemeyer. After three years of Postdoc under the guidance of Helmut Ringsdorf at the Johannes Gutenberg University Mainz, Finkelmann habilitated from 1978 to 1984 at the Clausthal University of Technology with the group of Günther Rehage. From 1984 to 2010 Finkelmann was appointed Full Professor and Director of the Institute for Macromolecular Chemistry at the Albert Ludwig University of Freiburg.<ref name=unileben02/2010></ref> One of his famous works is the concept of the side chain nematic elastomers. </ref> | https://en.wikipedia.org/wiki?curid=23681722 |
Colloid and Polymer Science is a peer-reviewed scientific journal which publishes in the field of colloid and polymer science and its interdisciplinary interactions. The journal is published by Springer Science+Business Media. It was first published in 1906. "Colloid and Polymer Science" had a 2013 impact factor of 2.430, whereas 2015 the impact factor was 1.890. The journal is ranked 28th out of 73 in the subject category "Polymer Science" and 61st out of 113 in "Physical Chemistry". The editors in chief of the journal are C.M. Papadakis (TU Munich) and A. Schmidt (U Köln), and chief advisory editor is F. Kremer (University Leipzig). | https://en.wikipedia.org/wiki?curid=23687090 |
Journal of Thermal Analysis and Calorimetry The is a peer-reviewed scientific journal published by Springer Science+Business Media in cooperation with Akadémiai Kiadó. Formerly this journal was known as Journal of Thermal Analysis. It publishes papers covering all aspects of calorimetry, thermal analysis, and experimental thermodynamics. Some of the subjects covered are thermogravimetry, differential scanning calorimetry of all types, derivative thermogravimetry, thermal conductivity, thermomechanical analysis, and the theory and instrumentation for thermal analysis and calorimetry. The "Journal of Thermal Analysis and Calorimetry" had a 2014 impact factor of 2.042, ranking it 37th out of 74 in the subject category 'Analytical Chemistry' and 75th out of 139 in 'Physical Chemistry'. The editor in chief of this journal is Alfréd Kállay-Menyhárd(Budapest University of Technology and Economics). The deputy editor in chief of this journal is Imre Miklós Szilágyi(Budapest University of Technology and Economics). | https://en.wikipedia.org/wiki?curid=23688022 |
Chromatographia is a peer-reviewed scientific journal published by Springer Verlag, covering liquid and gas chromatography, as well as electrophoresis and TLC. "Chromatographia" had a 2014 impact factor of 1.411, ranking it 50th out of 74 in the subject category "Analytical Chemistry" and 65th out of 79 in "Biochemical Research Methods". | https://en.wikipedia.org/wiki?curid=23688326 |
Journal of Radioanalytical and Nuclear Chemistry The is a peer-reviewed scientific journal published by Springer Science+Business Media. It publishes original papers, review papers, short communications and letters on nuclear chemistry. Some of the subjects covered are nuclear chemistry, radiation chemistry, nuclear power plant chemistry, radioanalytical chemistry, and environmental radiochemistry. The "Journal of Radioanalytical and Nuclear Chemistry" had a 2014 impact factor of 1.034, ranking it 15th out of 34 in the subject category "Nuclear Science and Technology", 57th out of 74 in "Analytical Chemistry", and 31st out of 44 in "Inorganic and Nuclear Chemistry". The founding editor in chief is Tibor Braun. This journal is indexed by the following services: | https://en.wikipedia.org/wiki?curid=23688529 |
C20H24N2O2 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23688981 |
C18H32O16 The molecular formula CHO (molar mass: 504.42 g/mol, exact mass: 504,169035) may refer to: | https://en.wikipedia.org/wiki?curid=23689103 |
C20H30O The molecular formula CHO (molar mass: 286.45 g/mol, exact mass: 286.229666 u) may refer to: | https://en.wikipedia.org/wiki?curid=23689214 |
C23H22O6 The molecular formula CHO (molar mass: 394 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23689416 |
C10H14NO5PS The molecular formula CHNOPS may refer to: | https://en.wikipedia.org/wiki?curid=23690196 |
Hexagonal crystal family In crystallography, the hexagonal crystal family is one of the six crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. The hexagonal crystal family consists of two lattice systems: hexagonal and rhombohedral. Each lattice system consists of one Bravais lattice. In the hexagonal family, the crystal is conventionally described by a right rhombic prism unit cell with two equal axes ("a" by "a"), an included angle of 120° ("γ") and a height ("c", which can be different from "a") perpendicular to the two base axes. The hexagonal unit cell for the rhombohedral Bravais lattice is the R-centered cell, consisting of two additional lattice points which occupy one body diagonal of the unit cell. There are two ways to do this, which can be thought of as two notations which represent the same structure. In the usual so-called obverse setting, the additional lattice points are at coordinates (, , ) and (, , ), whereas in the alternative reverse setting they are at the coordinates (,) and (,) | https://en.wikipedia.org/wiki?curid=23690287 |
Hexagonal crystal family In either case, there are 3 lattice points per unit cell in total and the lattice is non-primitive. The Bravais lattices in the hexagonal crystal family can also be described by rhombohedral axes. The unit cell is a rhombohedron (which gives the name for the rhombohedral lattice). This is a unit cell with parameters "a" = "b" = "c"; "α" = "β" = "γ" ≠ 90°. In practice, the hexagonal description is more commonly used because it is easier to deal with a coordinate system with two 90° angles. However, the rhombohedral axes are often shown (for the rhombohedral lattice) in textbooks because this cell reveals "m" symmetry of crystal lattice. The rhombohedral unit cell for the hexagonal Bravais lattice is the D-centered cell, consisting of two additional lattice points which occupy one body diagonal of the unit cell with coordinates (, , ) and (, , ). However, such a description is rarely used. The hexagonal crystal family consists of two crystal systems: trigonal and hexagonal. A crystal system is a set of point groups in which the point groups themselves and their corresponding space groups are assigned to a lattice system (see table in Crystal system#Crystal classes). The trigonal crystal system consists of the 5 point groups that have a single three-fold rotation axis, which includes space groups 143 to 167. These 5 point groups have 7 corresponding space groups (denoted by R) assigned to the rhombohedral lattice system and 18 corresponding space groups (denoted by P) assigned to the hexagonal lattice system | https://en.wikipedia.org/wiki?curid=23690287 |
Hexagonal crystal family The hexagonal crystal system consists of the 7 point groups that have a single six-fold rotation axis. These 7 point groups have 27 space groups (168 to 194), all of which are assigned to the hexagonal lattice system. Graphite is an example of a crystal that crystallizes in the hexagonal crystal system. The trigonal crystal system is the only crystal system whose point groups have more than one lattice system associated with their space groups: the hexagonal and rhombohedral lattices both appear. The 5 point groups in this crystal system are listed below, with their international number and notation, their space groups in name and example crystals. The point groups ("crystal classes") in this crystal system are listed below, followed by their representations in Hermann–Mauguin or international notation and Schoenflies notation, and mineral examples, if they exist. Hexagonal close packed (hcp) is one of the two simple types of atomic packing with the highest density, the other being the face centered cubic (fcc). However, unlike the fcc, it is not a Bravais lattice as there are two nonequivalent sets of lattice points. Instead, it can be constructed from the hexagonal Bravais lattice by using a two atom motif (the additional atom at about (,)) associated with each lattice point. Quartz is a crystal that belongs to the hexagonal lattice system but exists in two polymorphs that are in two different crystal systems | https://en.wikipedia.org/wiki?curid=23690287 |
Hexagonal crystal family The crystal structures of α-quartz are described by two of the 18 space groups (152 and 154) associated with the trigonal crystal system, while the crystal structures of β-quartz are described by two of the 27 space groups (180 and 181) associated with the hexagonal crystal system. The lattice angles and the lengths of the lattice vectors are all the same for both the cubic and rhombohedral lattice systems. The lattice angles for simple cubic, face-centered cubic, and body-centered cubic lattices are /2 radians, /3 radians, and radians, respectively. A rhombohedral lattice will result from lattice angles other than these. | https://en.wikipedia.org/wiki?curid=23690287 |
C10H13NO2 The molecular formula CHNO (molar mass : 179.21 g/mol, exact mass : 179.094629) may refer to: | https://en.wikipedia.org/wiki?curid=23691205 |
C17H25N The molecular formula CHN (molar mass : 243.394 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23691736 |
C12H12N2O3 The molecular formula CHNO (molar mass : 232.23 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23691792 |
C17H25NO The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23692110 |
C8H6O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23692741 |
C7H12O4 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23692908 |
C8H6O3 The molecular formula CHO (molar mass: 150.13 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23692995 |
C12H24 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23693101 |
C12H18 The molecular formula CH (molar mass: 162.27 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23693221 |
C21H36 The molecular formula CH (molar mass: 288.519 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23693242 |
C27H48 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23693260 |
C30H54 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23693267 |
Ignatius Gottfried Kaim was an Austrian chemist. In his dissertation "De metallis dubiis" published in 1770 Kaim describes the reduction of manganese oxide with carbon and the formation of a brittle metal. This is the first description of managanese metal several years before the better known synthesis of Johan Gottlieb Gahn in 1774. | https://en.wikipedia.org/wiki?curid=23699256 |
Polymer Bulletin is a peer-reviewed scientific journal published by Springer Science+Business Media, covering polymer science, including chemistry, physics, physical chemistry, and material science. "Polymer Bulletin" had a 2018 impact factor of 1.858, ranking it 37th out of 73 in "Polymer Science". The Editors of the journal are Jochen Gutmann, Noriyoshi Matsumi, Eva Malmström Jonsson and Daewon Sohn. Klaus Müllen is the Honorary Editor of the journal. Associate Editors are Günther Auernhammer, Patrick Burch, Youssef Habibi and Gilberto Siqueira. | https://en.wikipedia.org/wiki?curid=23699395 |
Journal of the American Oil Chemists' Society The is a peer-reviewed scientific journal published by Wiley and the American Oil Chemists' Society. The journal publishes original research articles, letters, and invited reviews in the area of science and technology of oils, fats, oilseed proteins, and related materials. The "Journal of the American Oil Chemists' Society" has a 2014 impact factor of 1.541 The editor in chief of the journal is Richard W. Hartel (University of Wisconsin). | https://en.wikipedia.org/wiki?curid=23699469 |
Jöns Jacob Berzelius Baron (; 20 August 1779 – 7 August 1848) was a Swedish chemist. Berzelius is considered, along with Robert Boyle, John Dalton, and Antoine Lavoisier, to be one of the founders of modern chemistry. Berzelius became a member of the Royal Swedish Academy of Sciences in 1808 and served from 1818 as its principal functionary. He is known in Sweden as the "Father of Swedish Chemistry". Berzelius Day is celebrated on 20 August in honour of him. Although Berzelius began his career as a physician, his enduring contributions were in the fields of electrochemistry, chemical bonding and stoichiometry. In particular, he is noted for his determination of atomic weights and his experiments that led to a more complete understanding of the principles of stoichiometry, which is the branch of chemistry pertaining to the quantitative relationships between elements in chemical compounds and chemical reactions and that these occur in definite proportions. This understanding came to be known as the "Law of Constant Proportions". Berzelius was a strict empiricist, expecting that any new theory must be consistent with the sum of contemporary chemical knowledge. He developed improved methods of chemical analysis, which were required to develop the basic data in support of his work on stoichiometry. He investigated isomerism, allotropy, and catalysis, phenomena that owe their names to him. Berzelius was among the first to articulate the differences between inorganic compounds and organic compounds | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius Among the many minerals and elements he studied, he is credited with discovering cerium and selenium, and with being the first to isolate silicon and thorium. Following on his interest in mineralogy, Berzelius synthesized and chemically characterized new compounds of these and other elements. Berzelius demonstrated the use of an electrochemical cell to decompose certain chemical compounds into pairs of electrically opposite constituents. From this research, he articulated a theory that came to be known as electrochemical dualism, contending that chemical compounds are oxide salts, bonded together by electrostatic interactions. This theory, while useful in some contexts, came to be seen as insufficient. Berzelius's work with atomic weights and his theory of electrochemical dualism led to his development of a modern system of chemical formula notation that showed the composition of any compound both qualitatively and quantitatively. His system abbreviated the Latin names of the elements with one or two letters and applied superscripts to designate the number of atoms of each element present in the compound. Later, chemists changed to use of subscripts rather than superscripts. Berzelius was born in the parish of Väversunda in Östergötland in Sweden. His father Samuel Berzelius was a school teacher in the nearby city of Linköping, and his mother Elizabeth Dorothea Sjösteen was a homemaker. His parents were both from families of church pastors. Berzelius lost both his parents at an early age | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius His father died in 1779, after which his mother married a pastor Anders Eckmarck, who gave Berzelius a basic education including knowledge of the natural world. Following the death of his mother in 1787, relatives in Linköping took care of him. There he attended the school today known as Katedralskolan. As a teenager, he took a position as a tutor at a farm nearby his home, during which time he became interested in collecting flowers and insects and their classification. Berzelius later enrolled as a medical student at Uppsala University, from 1796 to 1801. Anders Gustaf Ekeberg, the discoverer of tantalum, taught him chemistry during this time. He worked as an apprentice in a pharmacy, during which time he also learned practical matters in the laboratory such as glassblowing. On his own during his studies, he successfully repeated the experimentation conducted by Swedish chemist Carl William Scheele which led to Scheele's discovery of oxygen. He also worked with a physician in the Medevi mineral springs. During this time, he conducted an analysis of the water from this source. Additionally as part of his studies, in 1800 Berzelius learned about Alessandro Volta's electric pile, the first device that could provide a constant electric current (i.e., the first battery). He constructed a similar battery for himself, consisting of alternating disks of copper and zinc, and this was his initial work in the field of electrochemistry | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius As thesis research in his medical studies, he examined the influence of galvanic current on several diseases. This line of experimentation produced no clear cut evidence for such influence. Berzelius graduated as a medical doctor in 1802. He worked as a physician near Stockholm until the chemist and mine-owner Wilhelm Hisinger recognized his abilities as an analytical chemist and provided him with a laboratory. In 1807, Berzelius was appointed professor in chemistry and pharmacy at the Karolinska Institute. Between 1808 and 1836, Berzelius worked together with Anna Sundström, who acted as his assistant and was the first female chemist in Sweden. In 1808, he was elected a member of the Royal Swedish Academy of Sciences. At this time, the Academy had been stagnating for several years, since the era of romanticism in Sweden had led to less interest in the sciences. In 1818, Berzelius was elected the Academy's secretary and held the post until 1848. During Berzelius' tenure, he is credited with revitalising the Academy and bringing it into a second golden era (the first being the astronomer Pehr Wilhelm Wargentin's period as secretary from 1749 to 1783). He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1822. In 1827, he became correspondent of the Royal Institute of the Netherlands, and in 1830 associate member. In 1837, he was elected a member of the Swedish Academy, on chair number 5. Through much of his life, Berzelius suffered various medical ailments | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius These included recurrent migraine headaches and then later on he suffered from gout. He also had episodes of depression. In 1818, Berzelius had a nervous breakdown, said to be due to the stress of his work. The medical advice he received was to travel and take vacation. However, during this time, Berzelius traveled to France to work in the chemical laboratories of Claude Louis Berthollet. In 1835, at the age of 56, he married Elisabeth Poppius, the 24-year-old daughter of a Swedish cabinet minister. He died on 7 August 1848 at his home in Stockholm, where he had lived since 1806. He is buried in the Solna Cemetery. Soon after arriving in Stockholm, Berzelius wrote a chemistry textbook for his medical students, "Lärboki Kemien", which was his first significant scientific publication. He had conducted experimentation, in preparation for writing this textbook, on the compositions of inorganic compounds, which was his earliest work on definite proportions. In 1813, he published an essay on the proportions of elements in compounds. The essay commenced with a general description, introduced his new symbolism, examined all the known elements, included a table of specific weights, and finished with a selection of compounds written in his new formalism. In 1818, he compiled a table of relative atomic weights, where oxygen was set to 100, and which included all of the elements known at the time | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius This work provided evidence in favour of the atomic theory proposed by John Dalton: that inorganic chemical compounds are composed of atoms of different elements combined in whole number amounts. In discovering that atomic weights are not integer multiples of the weight of hydrogen, Berzelius also disproved Prout's hypothesis that elements are built up from atoms of hydrogen. Berzelius's last revised version of his atomic weight tables was first published in a German translation of his "Textbook of Chemistry" in 1826. In order to aid his experiments, he developed a system of chemical notation in which the elements composing any particular chemical compound were given simple written labels—such as O for oxygen, or Fe for iron—with their proportions in the chemical compound denoted by numbers. Berzelius thus invented the system of chemical notation still used today, the main difference being that instead of the subscript numbers used today (e.g., HO or FeO), Berzelius used superscripts (HO or FeO). Berzelius is credited with discovering the chemical elements cerium and selenium and with being the first to isolate silicon and thorium. Berzelius discovered cerium in 1803 and selenium in 1817.. Berzelius discovered how to isolate silicon in 1824, and thorium in 1824. Students working in Berzelius's laboratory also discovered lithium, lanthanum, and vanadium. Berzelius discovered silicon by repeating an experiment performed by Gay-Lussac and Thénard | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius In the experiment, Berzelius reacted silicon tetrafluoride with potassium metal and then purified its product by washing it until it became a brown powder. Berzelius recognized this brown powder as the new element of silicon, which he called silicium, a name proposed earlier by Davy. Berzelius was the first to isolate zirconium in 1824, but pure zirconium was not produced until 1925, by Anton Eduard van Arkel and Jan Hendrik de Boer. Berzelius is credited with originating the chemical terms "catalysis," "polymer," "isomer," "protein" and "allotrope," although his original definitions in some cases differ significantly from modern usage. As an example, he coined the term "polymer" in 1833 to describe organic compounds which shared identical empirical formulas but which differed in overall molecular weight, the larger of the compounds being described as "polymers" of the smallest. At this time the concept of chemical structure had not yet been developed so that he considered only the numbers of atoms of each element. in this way, he viewed for example glucose (CHO) as a polymer of formaldehyde (CHO), even though glucose is not a polymer from the monomer formaldehyde, indicating that his definition of the term "polymer" was inadequate. Berzelius was the first person to make the distinction between organic compounds (those containing carbon), and inorganic compounds. In particular, he advised Gerardus Johannes Mulder in his elemental analyses of organic compounds such as coffee, tea, and various proteins | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius The term "protein" itself was coined by Berzelius, after Mulder observed that all proteins seemed to have the same empirical formula and came to the erroneous conclusion that they might be composed of a single type of very large molecule. The term is derived from the Greek, meaning "of the first rank", and Berzelius proposed the name because proteins were so fundamental to living organisms. In 1808, Berzelius discovered that lactic acid occurs in muscle tissue, not just in milk. He also determined that lactic acid occurs in two different optical isomers. Berzelius stated in 1810 that living things work by some mysterious "vital force", a hypothesis called vitalism. Vitalism had first been proposed by prior researchers, although Berzelius contended that compounds could be distinguished by whether they required any organisms in their manufacture (organic compounds) or whether they did not (inorganic compounds). However, in 1828, Friedrich Wöhler accidentally obtained urea, an organic compound, by heating ammonium cyanate. This showed that an organic compound such as urea could be prepared synthetically and not exclusively by living organisms. Berzelius corresponded with Wöhler on the urea synthesis findings. However, the notion of vitalism continued to persist, until further work on abiotic synthesis of organic compounds providing overwhelming evidence against vitalism | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius Berzelius was a prolific correspondent with leading scientists of his time, such as Gerardus Johannes Mulder, Claude Louis Berthollet, Humphry Davy, Friedrich Wöhler and Eilhard Mitscherlich. In 1812, Berzelius traveled to London, England, including Greenwich to meet with prominent British scientists of the time. These included Humphry Davy, chemist William Wollaston, physician-scientist Thomas Young, astronomer William Herschel, chemist Smithson Tennant, and inventor James Watt, among others. Berzelius also visited Davy's laboratory. After his visit to Davy's laboratory, Berzelius remarked, "A tidy laboratory is a sign of a lazy chemist." Humphry Davy in 1810 proposed that chlorine is an element. Berzelius refuted this claim because of his belief that all acids were based on oxygen, and HCl contains no oxygen and so could not be an element, in Berzelius's perception. However, in 1812, Bernard Courtois proved that the isoelectronic substance iodine is an element. This finding resolved Berzelius's disagreement. Berzelius continued his investigations into the chemistry of chlorine during his stay in Claude Louis Berthollet's laboratory. In 1818 Berzelius was ennobled by King Carl XIV Johan. In 1835, he received the title of friherre. The Royal Society of London gave Berzelius the Copley Medal in 1836 with the citation "For his systematic application of the doctrine of definite proportions to the analysis of mineral bodies, as contained in his Nouveau Systeme de Mineralogie, and in other of his works | https://en.wikipedia.org/wiki?curid=23701666 |
Jöns Jacob Berzelius " In 1840, Berzelius was named Knight of the Order of Leopold. In 1842, he received the honor Pour le Mérite for Sciences and Arts. The mineral berzelianite, a copper selenide, was discovered in 1850 and named after him by James Dwight Dana. In 1852, Stockholm, Sweden, built a public park and statue, both to honor Berzelius. Berzeliusskolan, a school situated next to his alma mater, Katedralskolan, is named for him. In 1898, the Swedish Academy of Sciences opened the Berzelius Museum in honor of Berzelius. The holdings of the museum included many items from his laboratory. The museum was opened on the occasion of fiftieth anniversary of Berzelius's death. Invitees at the ceremony marking the occasion included scientific dignitaries from eleven European nations and the United States, many of whom gave formal addresses in honor of Berzelius. The Berzelius Museum was later moved to the observatory that is part of the Swedish Academy of Sciences. In 1939 his portrait appeared on a series of postage stamps commemorating the bicentenary of the founding of the Swedish Academy of Sciences. In addition to Sweden, Grenada likewise honored him. The Berzelius secret society at Yale University is named in his honor. | https://en.wikipedia.org/wiki?curid=23701666 |
Thomas R. Cundari is regents professor of chemistry at the University of North Texas and co-director of the Center for Advanced Scientific Computing and Modeling (CASCaM). Dr. Cundari received his B.S. in 1986 from Pace University in New York City and his Ph.D. in 1990 from the University of Florida. From 1990–1991 he was a postdoctoral fellow at North Dakota State University. After serving 11 years on the faculty at the University of Memphis, Dr. Cundari joined the UNT faculty in Fall, 2002. Dr. Cundari is one of two co-editors of "Reviews in Computational Chemistry", the foremost monograph series in the field. He is on the editorial board of "". Tom Cundari was chosen to participate in one of the 46 funded Energy Frontier Research Centers (EFRCs). The project is led by long-time Cundari Group collaborator, Prof. T. Brent Gunnoe (chemistry, University of Virginia). The UNT team will work with leading researchers from the University of Virginia, Yale University, Princeton University, the California Institute of Technology, University of North Carolina-Chapel Hill, the Scripps Research Institute, Brigham Young University, Colorado School of Mines, and the University of Maryland to identify novel catalysts for meeting the U.S.'s energy needs. The UNT team along with groups at BYU and Caltech will provide the lead in modeling and simulation research within this EFRC, entitled "Center for Catalytic Hydrocarbon Functionalization". | https://en.wikipedia.org/wiki?curid=23702239 |
C2H2Cl2 CHCl may refer to: | https://en.wikipedia.org/wiki?curid=23705121 |
Magmatic water or juvenile water is water that exists within, and in equilibrium with, a magma or water-rich volatile fluids that are derived from a magma. This magmatic water is released to the atmosphere during a volcanic eruption. may also be released as hydrothermal fluids during the late stages of magmatic crystallization or solidification within the Earth's crust. The crystallization of hydroxyl bearing amphibole and mica minerals acts to contain part of the magmatic water within a solidified igneous rock. Ultimate sources of this magmatic water includes water and hydrous minerals in rocks melted during subduction as well as primordial water brought up from the deep mantle. Water has limited solubility in silicate melts ranging from almost 0% at surface pressure to 10% at 1100 °C and 5 kbar of pressure for a granitic melt. Solubility is lower for more mafic magmas. As the temperature and pressure drop during emplacement and cooling of the magma a separate aqueous phase will exsolve. This aqueous phase will be enriched in other volatile and silicate incompatible species such as the metals: copper, lead, zinc, silver and gold; alkalis and alkaline earths and others, including: lithium, beryllium, boron, rubidium; and volatiles: fluorine, chlorine and carbon dioxide. Water in silicate melts at the high temperature and pressure conditions within the crust exists as a supercritical fluid rather than in a gaseous state (the critical point for water is at 374 °C and 218 bar) | https://en.wikipedia.org/wiki?curid=23708860 |
Magmatic water Stable isotope studies of oxygen and hydrogen in igneous rocks indicate that the oxygen-18 (δO) content is approximately 6–8‰ higher than standard mean ocean water (SMOW) while the deuterium (δH) content is 40 to 80‰ lower than SMOW. Water in equilibrium with igneous melts should bear the same isotopic signature for oxygen-18 and deuterium. Isotope data on hydrothermal solutions spatially associated with igneous intrusions should reflect this isotopic signature. However, isotopic studies of hydrothermal waters indicate that most bear the isotopic signature of meteoric water. Any magmatic waters in these hydrothermal solutions must have been swamped by the circulating meteoric groundwaters of the environment. Fluid inclusions are microscopic bubbles of aqueous solutions which were trapped within crystals during crystallization and are considered as relic samples of the mineralizing waters. Analyses of the isotopic content of these trapped bubbles show a wide range of δO and δH content. All examined show an enrichment in O and depletion in H relative to SMOW and meteoric waters. Fluid inclusion data from a number of ore deposits plot directly on the magmatic water "region" of an δO vs δH plot. | https://en.wikipedia.org/wiki?curid=23708860 |
Monoaminergic means "working on monoamine neurotransmitters", which include serotonin, dopamine, norepinephrine, epinephrine, and histamine. A monoaminergic, or monoaminergic drug, is a chemical which functions to directly modulate the serotonin, dopamine, norepinephrine, epinephrine, and/or histamine neurotransmitter systems in the brain. Monoaminergics include catecholaminergics (which can be further divided into adrenergics and dopaminergics), serotonergics, and histaminergics. An example of a class of monoaminergic drugs is monoamine oxidase inhibitors (MAOIs). | https://en.wikipedia.org/wiki?curid=23713109 |
C6H9NO The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23714114 |
C12H18N2O2 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23714121 |
C15H21N3O The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23714218 |
C13H20N2O2 The molecular formula CHNO (molar mass : 236.31 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23714226 |
Replikins are a group of peptides, whose increase in concentration in virus or other organism proteins is associated with rapid replication. It is often measured in number of replikins per 100 amino acids. This particular group of peptides have been found to play a significant role in predicting both infectivity and lethality of various viral strains. In particular, this group allowed the prediction of the A/H1N1 pandemic almost one year before onset. A method for identifying replikins was patented by Samuel and Elenore S. Bogoch in 2001. The peptide group was first identified by a proprietary company called Replikins, who have trademarked the name "Replikin Count". | https://en.wikipedia.org/wiki?curid=23715102 |
Time-lapse microscopy is time-lapse photography applied to microscopy. Microscope image sequences are recorded and then viewed at a greater speed to give an accelerated view of the microscopic process. Before the introduction of the video tape recorder in the 1960s, time-lapse microscopy recordings were made on photographic film. During this period, time-lapse microscopy was referred to as microcinematography. With the increasing use of video recorders, the term time-lapse video microscopy was gradually adopted. Today, the term video is increasingly dropped, reflecting that a digital still camera is used to record the individual image frames, instead of a video recorder. can be used to observe any microscopic object over time. However, its main use is within cell biology to observe artificially cultured cells. Depending on the cell culture, different microscopy techniques can be applied to enhance characteristics of the cells as most cells are transparent. To enhance observations further, cells have therefore traditionally been stained before observation. Unfortunately, the staining process kills the cells. The development of less destructive staining methods and methods to observe unstained cells has led to that cell biologists increasingly observe living cells. This is known as live cell imaging. A few tools have been developed to identify and analyze single cells during live cell imaging | https://en.wikipedia.org/wiki?curid=23716097 |
Time-lapse microscopy is the method that extends live cell imaging from a single observation in time to the observation of cellular dynamics over long periods of time. is primarily used in research, but is clinically used in IVF clinics as studies has proven it to increase pregnancy rates, lower abortion rates and predict aneuploidy Modern approaches are further extending time-lapse microscopy observations beyond making movies of cellular dynamics. Traditionally, cells have been observed in a microscope and measured in a cytometer. Increasingly this boundary is blurred as cytometric techniques are being integrated with imaging techniques for monitoring and measuring dynamic activities of cells and subcellular structures. "The Cheese Mites" by Martin Duncan from 1903 is one of the earliest microcinematographic films. However, the early development of scientific microcinematography took place in Paris. The first reported time-lapse microscope was assembled in the late 1890s at the Marey Institute, founded by the pioneer of chronophotography, Étienne-Jules Marey. It was, however, Jean Comandon who made the first significant scientific contributions in around 1910. Comandon was a trained microbiologist specializing in syphilis research. Inspired by Victor Henri's microcinematic work on Brownian motion, he used the newly invented ultramicroscope to study the movements of the syphilis bacteria. At the time, the ultramicroscope was the only microscope in which the thin spiral shaped bacteria was visible | https://en.wikipedia.org/wiki?curid=23716097 |
Time-lapse microscopy Using an enormous cinema camera bolted to the fragile microscope, he demonstrated visually that the movement of the disease-causing bacteria is uniquely different from the non-disease-causing form. Comandon's films proved instrumental in teaching doctors how to distinguish the two forms. Comandon's extensive pioneering work inspired others to adopt microcinematography. Heniz Rosenberger builds a microcinematograph in the mid 1920s. In collerboration with Alexis Carrel, they used the device to further develop Carrel's cell culturing techniques. Similar work was conducted by Warren Lewis. During World War II, Carl Zeiss AG released the first phase-contrast microscope on the market. With this new microscope, cellular details could for the first time be observed without using lethal stains. By setting up some of the first time-lapse experiments with chicken fibroblasts and a phase-contrast microscope, Michael Abercrombie described the basis of our current understanding of cell migration in 1953. With the broad introduction of the digital camera at the beginning of this century, time-lapse microscopy has been made dramatically more accessible and is currently experiencing an unrepresented raise in scientific publications. | https://en.wikipedia.org/wiki?curid=23716097 |
C5H4N4 The molecular formula CHN may refer to: | https://en.wikipedia.org/wiki?curid=23717143 |
C4H12N2 The molecular formula CHN may refer to: | https://en.wikipedia.org/wiki?curid=23717161 |
C5H5NO The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23717280 |
C8H9NO3 The molecular formula CHNO (molar mass: 167.16 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23717286 |
C17H23N3O The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23717321 |
C10H10O2 The molecular formula CHO (molar mass : 162.18 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23717469 |
C13H18O7 The molecular formula CHO (molar mass : 286.28 g/mol, react mass : 286.105253 u) may refer to : | https://en.wikipedia.org/wiki?curid=23717479 |
C7H6O3 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23717513 |
Tessaleno Devezas Tessaleno Campos Devezas (born 4 December 1946 in Rio de Janeiro) is a Brazilian-born Portuguese physicist, systems theorist, and materials scientist. He is best known for his contributions to the long waves theory in socioeconomic development, technological evolution, energy systems as well as world system analysis. In March 2002, Devezas was honored with the "Elsevier Best Paper Prize 2001" for his paper proposing a model explaining the mechanism underlying the long economic waves (Kondratieff waves) and, in 2006, another of his papers (about the growth dynamics of the Internet) received an Honor Mention from Elsevier. In 2004, he was awarded with the Silver Kondratieff Medal by the International N. D. Kondratieff Foundation and the Russian Academy of Natural Sciences (RAEN) for his written contributions for the understanding of the Kondratieff waves, and, in 2005, he was honored as Honorary Member of the International Kondratieff Foundation. The following list does not include this author's publications on materials science and engineering. | https://en.wikipedia.org/wiki?curid=23718577 |
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