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Solar cell Exxon, ARCO, Shell, Amoco (later purchased by BP) and Mobil all had major solar divisions during the 1970s and 1980s. Technology companies also participated, including General Electric, Motorola, IBM, Tyco and RCA. Adjusting for inflation, it cost $96 per watt for a solar module in the mid-1970s. Process imp...
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Solar cell During the 1990s, polysilicon ("poly") cells became increasingly popular. These cells offer less efficiency than their monosilicon ("mono") counterparts, but they are grown in large vats that reduce cost. By the mid-2000s, poly was dominant in the low-cost panel market, but more recently the mono returned to...
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Solar cell Solar-specific feed-in tariffs vary by country and within countries. Such tariffs encourage the development of solar power projects. Widespread grid parity, the point at which photovoltaic electricity is equal to or cheaper than grid power without subsidies, likely requires advances on all three fronts. Prop...
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Solar cell (The abbreviation Wp stands for watt peak capacity, or the maximum capacity under optimal conditions.) As of the end of 2016, it was reported that spot prices for assembled solar "panels" (not cells) had fallen to a record-low of US$0.36/Wp. The second largest supplier, Canadian Solar Inc., had reported cost...
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Solar cell The overall efficiency is the product of these individual metrics. The power conversion efficiency of a solar cell is a parameter which is defined by the fraction of incident power converted into electricity. A solar cell has a voltage dependent efficiency curve, temperature coefficients, and allowable shado...
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Solar cell In the extreme, with an infinite number of layers, the corresponding limit is 86% using concentrated sunlight. In 2014, three companies broke the record of 25.6% for a silicon solar cell. Panasonic's was the most efficient. The company moved the front contacts to the rear of the panel, eliminating shaded are...
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Solar cell In addition, the dual-junction device was mechanically stacked with a Si solar cell, to achieve a record one-sun efficiency of 35.9% for triple-junction solar cells. Solar cells are typically named after the semiconducting material they are made of. These materials must have certain characteristics in order ...
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Solar cell Many use organic materials, often organometallic compounds as well as inorganic substances. Despite the fact that their efficiencies had been low and the stability of the absorber material was often too short for commercial applications, there is a lot of research invested into these technologies as they pro...
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Solar cell Solar cells made with this "kerfless" technique can have efficiencies approaching those of wafer-cut cells, but at appreciably lower cost if the CVD can be done at atmospheric pressure in a high-throughput inline process. The surface of epitaxial wafers may be textured to enhance light absorption. In June 20...
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Solar cell When sliced for processing, the inner sections are high-efficiency mono-like cells (but square instead of "clipped"), while the outer edges are sold as conventional poly. This production method results in mono-like cells at poly-like prices. Thin-film technologies reduce the amount of active material in a ce...
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Solar cell Silicon thin-film cells are mainly deposited by chemical vapor deposition (typically plasma-enhanced, PE-CVD) from silane gas and hydrogen gas. Depending on the deposition parameters, this can yield amorphous silicon (a-Si or a-Si:H), protocrystalline silicon or nanocrystalline silicon (nc-Si or nc-Si:H), al...
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Solar cell Although GaAs cells are very expensive, they hold the world's record in efficiency for a single-junction solar cell at 28.8%. GaAs is more commonly used in multijunction photovoltaic cells for concentrated photovoltaics (CPV, HCPV) and for solar panels on spacecrafts, as the industry favours efficiency over ...
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Solar cell Multi-junction cells were originally developed for special applications such as satellites and space exploration, but are now used increasingly in terrestrial concentrator photovoltaics (CPV), an emerging technology that uses lenses and curved mirrors to concentrate sunlight onto small, highly efficient mult...
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Solar cell GaAs based multi-junction devices are the most efficient solar cells to date. On 15 October 2012, triple junction metamorphic cells reached a record high of 44%. In 2016, a new approach was described for producing hybrid photovoltaic wafers combining the high efficiency of III-V multi-junction solar cells wi...
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Solar cell The two cells therefore are separated by a transparent glass slide so the lattice mismatch does not cause strain to the system. This creates a cell with four electrical contacts and two junctions that demonstrated an efficiency of 18.1%. With a fill factor (FF) of 76.2%, the Si bottom cell reaches an efficienc...
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Solar cell So far most types of perovskite solar cells have not reached sufficient operational stability to be commercialised, although many research groups are investigating ways to solve this. With a transparent rear side, bifacial solar cells can absorb light from both the front and rear sides. Hence, they can produ...
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Solar cell of bifacial solar cells, early landmarks of Isofoton's production were the 20kWp power plant in San Agustín de Guadalix, built in 1986 for Iberdrola, and an off grid installation by 1988 also of 20kWp in the village of Noto Gouye Diama (Senegal) funded by the Spanish international aid and cooperation program...
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Solar cell In addition, there is evidence that bifacial panels work better than traditional panels in snowy environments - as bifacials on dual-axis trackers made 14%t more electricity in a year than their monofacial counterparts and 40% during the peak winter months. An online simulation tool is available to model the...
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Solar cell In 2014, researchers at California NanoSystems Institute discovered using kesterite and perovskite improved electric power conversion efficiency for solar cells. Photon upconversion is the process of using two low-energy ("e.g.", infrared) photons to produce one higher energy photon; downconversion is the pr...
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Solar cell The excited ion emits light above the Si bandgap that is absorbed by the solar cell and creates an additional electron–hole pair that can generate current. However, the increased efficiency was small. In addition, fluoroindate glasses have low phonon energy and have been proposed as suitable matrix doped wit...
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Solar cell This type of cell allows more flexible use of materials and is typically manufactured by screen printing or ultrasonic nozzles, with the potential for lower processing costs than those used for bulk solar cells. However, the dyes in these cells also suffer from degradation under heat and UV light and the cel...
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Solar cell The electrical circuit is then completed through the use of a liquid or solid redox couple. The efficiency of QDSCs has increased to over 5% shown for both liquid-junction and solid state cells, with a reported peak efficiency of 11.91%. In an effort to decrease production costs, the Prashant Kamat research ...
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Solar cell Energy conversion efficiencies achieved to date using conductive polymers are very low compared to inorganic materials. However, Konarka Power Plastic reached efficiency of 8.3% and organic tandem cells in 2012 reached 11.1%. The active region of an organic device consists of two materials, one electron dono...
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Solar cell They used block copolymers, self-assembling organic materials that arrange themselves into distinct layers. The research focused on P3HT-b-PFTBT that separates into bands some 16 nanometers wide. Adaptive cells change their absorption/reflection characteristics depending on environmental conditions. An adapt...
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Solar cell Surface texturing is one of techniques used to reduce optical losses to maximize light absorbed. Currently, surface texturing techniques on silicon photovoltaics are drawing much attention. Surface texturing could be done in multiple ways. Etching single crystalline silicon substrate can produce randomly dis...
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Solar cell In 2012, researchers at MIT reported that c-Si films textured with nanoscale inverted pyramids could achieve light absorption comparable to 30 times thicker planar c-Si. In combination with anti-reflective coating, surface texturing technique can effectively trap light rays within a thin film silicon solar c...
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Solar cell Active coatings that convert infrared light into visible light have shown a 30% increase. Nanoparticle coatings inducing plasmonic light scattering increase wide-angle conversion efficiency up to 3%. Optical structures have also been created in encapsulation materials to effectively "cloak" the metallic fron...
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Solar cell A full area metal contact is made on the back surface, and a grid-like metal contact made up of fine "fingers" and larger "bus bars" are screen-printed onto the front surface using a silver paste. This is an evolution of the so-called "wet" process for applying electrodes, first described in a US patent file...
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Solar cell Global PV cell/module production increased by 10% in 2012 despite a 9% decline in solar energy investments according to the annual "PV Status Report" released by the European Commission's Joint Research Centre. Between 2009 and 2013 cell production has quadrupled. Since 2013 China has been the world's leadin...
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Solar cell This number is estimated to increase substantially by 2030, reaching an estimated waste volume of 60–78 million metric tons in 2050. Solar panels are recycled through different methods. The recycling process include a three step process, module recycling, cell recycling and waste handling, to break down Si m...
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Alizarine Yellow R is a yellow colored azo dye made by the diazo coupling reaction. It usually comes as a sodium salt. In its pure form it is a rust-colored solid. Its main use is as a pH indicator.
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Electrorotation is the circular movement of an electrically polarized particle. Similar to the slip of an electric motor, it can arise from a phase lag between an applied rotating electric field and the respective relaxation processes and may thus be used to investigate the processes or, if these are known or can be ac...
https://en.wikipedia.org/wiki?curid=2359746
Free-radical reaction A free-radical reaction is any chemical reaction involving free radicals. This reaction type is abundant in organic reactions. Two pioneering studies into free radical reactions have been the discovery of the triphenylmethyl radical by Moses Gomberg (1900) and the lead-mirror experiment described ...
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Free-radical reaction The overall reaction rate can be written as: with a broken-order dependence of 1.5 with respect to the initiating species. The reactivity of different compounds toward a certain radical is measured in so-called competition experiments. Compounds bearing carbon–hydrogen bonds react with radicals in...
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White fuming nitric acid (WFNA) is a storable liquid oxidizer used with kerosene and hydrazine rocket fuel. It consists of nearly pure nitric acid (). WFNA is commonly specified as containing no more than 2% water and less than 0.5% dissolved nitrogen dioxide or dinitrogen tetroxide. WFNA was sometimes used with an inh...
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Eckert number The (Ec) is a dimensionless number used in continuum mechanics. It expresses the relationship between a flow's kinetic energy and the boundary layer enthalpy difference, and is used to characterize heat transfer dissipation. It is named after Ernst R. G. Eckert. It is defined as where
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Internal conversion (chemistry) Internal conversion is a transition from a higher to a lower electronic state in a molecule or atom. It is sometimes called "radiationless de-excitation", because no photons are emitted. It differs from intersystem crossing in that, while both are radiationless methods of de-excitation, ...
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Internal conversion (chemistry) In applications that make use of bimolecular electron transfer the internal conversion is undesirable. For example, it is advantageous to have a long lived excited states in Grätzel cells (Dye-sensitized solar cells).
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Lawrence V. Redman (September 1, 1880 – November 26, 1946), was a Canadian chemist and businessman who spent much of his adult life in the United States. Redman was a pioneer in the industrial applications of plastics. Born in Oil Springs, Ontario, Redman took a B.A. degree from the University of Toronto in 1908. He co...
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Redmanol Chemical Products Company was an early plastics manufacturer formed in 1913. Lawrence V. Redman was its president. In 1922, the Redmanol Company, the Condensite Company of America, and General Bakelite were consolidated into the Bakelite Corporation.
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Natta projection The is a way to depict molecules with complete stereochemistry in two dimensions in a skeletal formula. This concept is named after Giulio Natta. In a hydrocarbon molecule with all carbon atoms making up the backbone in a tetrahedral molecular geometry, the zigzag backbone is in the paper plane (chemic...
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Abraum salts is the name given to a mixed deposit of salts, including halite (sodium chloride), carnallite, and kieserite (magnesium sulfate), found in association with rock salt at Aschersleben-Staßfurt in Germany. The term comes from the German "Abraum-salze", "salts to be removed." Abraum, which is red, is used to d...
https://en.wikipedia.org/wiki?curid=2365712
Full configuration interaction (or full CI) is a linear variational approach which provides numerically exact solutions (within the infinitely flexible complete basis set) to the electronic time-independent, non-relativistic Schrödinger equation. It is a special case of the configuration interaction method in which "al...
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Full configuration interaction Full CI problems including several million up to a few billion determinants are possible using current algorithms. Because full CI results are exact within the space spanned by the orbital basis set, they are invaluable in benchmarking approximate quantum chemical methods. This is particu...
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Plumbate In chemistry, a plumbate is a salt having one of the several lead-containing oxoanions. Although the term "plumbate" can refer either to plumbate(II) or plumbate(IV), it traditionally refers specifically to plumbate(IV), whereas plumbate(II) is referred to as "plumbite". Plumbates are formed by the reaction of...
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Tin(IV) oxide Tin(IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO. The mineral form of SnO is called cassiterite, and this is the main ore of tin. With many other names, this oxide of tin is an important material in tin chemistry. It is a colourless, diamagnetic, amphoteric solid....
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Tin(IV) oxide In conjunction with vanadium oxide, it is used as a catalyst for the oxidation of aromatic compounds in the synthesis of carboxylic acids and acid anhydrides. has long been used as an opacifier and as a white colorant in ceramic glazes. This has probably led to the discovery of the pigment lead-tin-yellow...
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Tin(IV) oxide SnO coatings can be applied using chemical vapor deposition, vapour deposition techniques that employ SnCl or organotin trihalides e.g. butyltin trichloride as the volatile agent. This technique is used to coat glass bottles with a thin (<0.1 μm) layer of SnO, which helps to adhere a subsequent, protectiv...
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Bond dipole moment The bond dipole moment uses the idea of electric dipole moment to measure the polarity of a chemical bond within a molecule. It occurs whenever there is a separation of positive and negative charges. The bond dipole μ is given by: The bond dipole is modeled as δ — δ with a distance "d" between the pa...
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Bond dipole moment At one extreme, a symmetrical molecule such as chlorine, , has zero dipole moment, while near the other extreme, gas phase potassium bromide, KBr, which is highly ionic, has a dipole moment of 10.5 D. For polyatomic molecules, there is more than one bond. The total molecular dipole moment may be appr...
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XDrawChem is a free software program for drawing chemical structural formulas, available for Unix and macOS. It is distributed under the GNU GPL. In Microsoft Windows this program is called WinDrawChem.
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Teijin The company is listed on the first section of the Tokyo Stock Exchange and is a constituent of the Nikkei 225 stock index. As of March 2014, the Group comprises 151 companies, 56 in Japan and 95 overseas. is a member of the Mitsubishi UFJ Financial Group (MUFJ) keiretsu.
https://en.wikipedia.org/wiki?curid=2369543
Glucagon-like peptide-2 (GLP-2) is a 33 amino acid peptide with the sequence HADGSFSDEMNTILDNLAARDFINWLIQTKITD (see Proteinogenic amino acid) in humans. GLP-2 is created by specific post-translational proteolytic cleavage of proglucagon in a process that also liberates the related glucagon-like peptide-1 (GLP-1). GLP-2...
https://en.wikipedia.org/wiki?curid=2370396
Ion beam analysis ("IBA") is an important family of modern analytical techniques involving the use of MeV ion beams to probe the composition and obtain elemental depth profiles in the near-surface layer of solids. All IBA methods are highly sensitive and allow the detection of elements in the sub-monolayer range. The d...
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Ion beam analysis To use these interactions to determine sample composition a technique must be selected along with irradiation conditions and the detection system that will best isolate the radiation of interest providing the desired sensitivity and detection limits. The basic layout of an ion beam apparatus is an acc...
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Ion beam analysis Even then, the use of ion beam analysis has not faded, and more applications are being found that take advantage of its superior detection capabilities. In an era where older technologies can become obsolete at an instant, ion beam analysis has remained a mainstay and only appears to be growing as res...
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Ion beam analysis More specifically, this technique offers unparalleled performance in terms of sensitivity and accuracy. Recently however, there have been competing sources for archaeometry purposes using X-ray based methods such as XRF. Nonetheless, the most preferred and accurate source is ion beam analysis, which i...
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Ion beam analysis By changing type of incident ion, the geometry of experiment, particle energy, or by acquiring different products originating from ion-solid interaction, complementary information can be extracted. However, analysis is often challenged either in terms of mass resolution - when several comparably heavy...
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Ion beam analysis Such changes are detailed through the five classes by which the updated software are categorized. Includes all programs developed in the late 1960s and early 1970s. This class of software solved specific problems in the data; niy did not provide the full potential to analyze a spectrum of a full gener...
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Ion beam analysis In a trip back to square one, this third class of programs, created in the 1990s, take a few principles from Class A in accounting for the general case, however, now through the use of indirect methods. RUMP and SENRAS, for example, use an assumed model of the sample and simulate a comparative theoret...
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Ion beam analysis A key and popular feature that accompanies such techniques is the possibility for the computations to be incorporated in real time with the ion beam analysis experiment itself.
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Surroundings are the area around a given physical or geographical point or place. The exact definition depends on the field. can also be used in geography (when it is more precisely known as vicinity, or vicinage) and mathematics, as well as philosophy, with the literal or metaphorically extended definition. In thermod...
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Calamine brass is brass produced by a particular alloying technique using the zinc ore calamine directly, rather than first refining it to metallic zinc. Direct zinc smelting appears to have been unknown in Europe until the mid-18th century, even though the alloyed calamine brass was in use for centuries, and metallic ...
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Calamine brass was the first type of brass produced, probably starting during the 1st millennium BC, and was not replaced in Europe by other brass manufactures until the 18th century (it is likely that Indian brass manufacturers had developed more advanced techniques some centuries earlier). The area around La Calamine...
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Calamine brass However, the conversion away from calamine brass manufacture was slow; a British patent was awarded to William Champion in 1738, but the alloying of metallic zinc and copper to produce brass was not patented until 1781 (by James Emerson), and calamine brass mills persisted in South Wales until as late as...
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Hexanitrostilbene (HNS), also called JD-X, is an organic compound with the formula [(ON)CHCH]. It is a yellow-orange solid. It is used as a heat-resistant high explosive. It is slightly soluble (0.1 - 5 g/100 mL) in butyrolactone, DMF, DMSO, and "N"-methylpyrrolidone. It is produced by oxidizing trinitrotoluene (TNT) w...
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Bioorthogonal chemical reporter In chemical biology, bioorthogonal chemical reporter is a non-native chemical functionality that is introduced into the naturally occurring biomolecules of a living system, generally through metabolic or protein engineering. These functional groups are subsequently utilized for tagging a...
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Polymer science or macromolecular science is a subfield of materials science concerned with polymers, primarily synthetic polymers such as plastics and elastomers. The field of polymer science includes researchers in multiple disciplines including chemistry, physics, and engineering. This science comprises three main s...
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Polymer science In 1884 Hilaire de Chardonnet started the first artificial fiber plant based on regenerated cellulose, or viscose rayon, as a substitute for silk, but it was very flammable. In 1907 Leo Baekeland invented the first synthetic plastic, a thermosetting phenol–formaldehyde resin called Bakelite. Despite sig...
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Polymer science The growth in industrial applications was mirrored by the establishment of strong academic programs and research institute. In 1946, Herman Mark established the Polymer Research Institute at Brooklyn Polytechnic, the first research facility in the United States dedicated to polymer research. Mark is als...
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Polymer science Flory for contributions to theoretical polymer chemistry. 1963 (Chemistry) Giulio Natta and Karl Ziegler for contributions in polymer synthesis. (Ziegler-Natta catalysis). 1953 (Chemistry) Hermann Staudinger for contributions to the understanding of macromolecular chemistry.
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Lead dioxide Lead(IV) oxide is the inorganic compound with the formula PbO. It is an oxide where lead is in an oxidation state of +4. It is a dark-brown solid which is insoluble in water. It exists in two crystalline forms. It has several important applications in electrochemistry, in particular as the positive plate o...
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Lead dioxide In addition, PbO can be obtained by decomposing PbO at 580–620 °C under an oxygen pressure of . Therefore, thermal decomposition of lead dioxide is a common way of producing various lead oxides. is an amphoteric compound with prevalent acidic properties. It dissolves in strong bases to form the hydroxyplum...
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Lead dioxide is produced commercially by several methods, which include oxidation of red lead (PbO) in alkaline slurry in a chlorine atmosphere, reaction of lead(II) acetate with "chloride of lime" (calcium hypochlorite), The reaction of PbO with nitric acid also affords the dioxide: PbO reacts with sodium hydroxide to...
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Lead dioxide It is also used in the construction of high-voltage lightning arresters. is used as an anode material in electrochemistry. β-PbO is more attractive for this purpose than the α form because it has relatively low resistivity, good corrosion resistance even in low-pH medium, and a high overvoltage for the evo...
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Carbon tetrafluoride Tetrafluoromethane, also known as carbon tetrafluoride or R-14, is the simplest fluorocarbon (CF). It has a very high bond strength due to the nature of the carbon–fluorine bond. It can also be classified as a haloalkane or halomethane. Tetrafluoromethane is a useful refrigerant but also a potent g...
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Carbon tetrafluoride Commercially it is manufactured by the reaction of hydrogen fluoride with dichlorodifluoromethane or chlorotrifluoromethane; it is also produced during the electrolysis of metal fluorides MF, MF using a carbon electrode. Although it can be made from myriad precursors and fluorine, elemental fluorin...
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Carbon tetrafluoride It is very stable, has an atmospheric lifetime of 50,000 years, and a high greenhouse warming potential of 6500 (which is given for the first 100 years thereof, CO has a factor of 1); however, the low amount in the atmosphere restricts the overall radiative forcing effect. Although structurally sim...
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Carbon tetrabromide Tetrabromomethane, CBr, also known as carbon tetrabromide, is a carbon bromide. Both names are acceptable under IUPAC nomenclature. Tetrabromomethane has two polymorphs: crystalline II or β below 46.9 °C (320.0 K) and crystalline I or α above 46.9 °C. Monoclinic polymorph has space group "C2/c" with...
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Carbon tetrabromide The combination of censored Frenkel disorder and displacive disorder implies a considerable amount of disorder inside the crystal which leads to highly structured sheets of diffuse scattered intensity in X-ray diffraction. In fact, it is the structure in the diffuse intensity that provides the infor...
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Smoke hood A smoke hood is a hood, similar in concept to a gas mask. A translucent airtight bag seals around the head of the wearer while an air filter held in the mouth connects to the outside atmosphere and is used to breathe. Smoke hoods are intended to protect victims of fire from the effects of smoke inhalation. A...
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Smoke hood In the end, Morgan's smoke hood enabled the rescue of many of the previous rescuers and allowed Morgan himself to make four trips into the tunnel—a journey that, without the hood, was not possible even once. High-quality smoke hoods are generally constructed of heat-resistant material like Kapton, and can wi...
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Smoke hood The oxygen is kept in a closed circuit, usually thanks to a tight neck seal. A scrubber system may be present to reduce the levels of carbon dioxide, and is breathable for around 20 minutes. When the oxygen supply ends, the hood will begin deflating and must be removed to avoid suffocation. These devices rep...
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Engineering plastic Engineering plastics are a group of plastic materials that have better mechanical and/or thermal properties than the more widely used commodity plastics (such as polystyrene, PVC, polypropylene and polyethylene). Being more expensive, engineering plastics are produced in lower quantities and tend to...
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Engineering plastic Other properties exhibited by various grades of engineering plastics include heat resistance, mechanical strength, rigidity, chemical stability, self lubrication (specially used in manufacturing of gears & skids) and fire safety. What are Engineering Plastics?
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Smoke point The smoke point, also referred to as the burning point, is the temperature at which an oil or fat begins to produce a continuous bluish smoke that becomes clearly visible, dependent upon specific and defined conditions. values can vary greatly, depending on factors such as the volume of oil utilized, the si...
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Smoke point Oxidative stability is the best predictor of how an oil behaves during cooking. The Rancimat method is one of the most common methods for testing oxidative stability in oils. This determination entails speeding up the oxidation process in the oil (under heat and forced air), which enables its stability to b...
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Hexamethylene triperoxide diamine (HMTD) is a high explosive organic compound. HMTD is an organic peroxide, a heterocyclic compound with a cage-like structure. It is a primary explosive. It has been considered as an initiating explosive for blasting caps in the early part of 20th century, mostly because of its high ini...
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Hexamethylene triperoxide diamine Common static electricity discharges have been reported to cause detonation. It is, however, less unstable than many other peroxides under normal conditions; exposure to ultraviolet light increases its sensitivity. It also reacts with most common metals, which can lead to detonation. H...
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Hexamethylene triperoxide diamine Calculated (Explo5) detonation pressure P at crystal density 1.597 g/cm is 218 kbar with velocity of detonation VoD = 7777 m/s. Explosion temperature is 3141 K, energy of explosion is 5612 kJ/kg (or 3400 - 4000 kJ/kg per various sources) and volume of explosion gases at STP is calculat...
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Liquid chromatography–mass spectrometry (LC-MS) is an analytical chemistry technique that combines the physical separation capabilities of liquid chromatography (or HPLC) with the mass analysis capabilities of mass spectrometry (MS). Coupled chromatography - MS systems are popular in chemical analysis because the indiv...
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Liquid chromatography–mass spectrometry Overall, the interface is a mechanically simple part of the LC-MS system that transfers the maximum amount of analyte, removes a significant portion of the mobile phase used in LC and preserves the chemical identity of the chromatography products (chemically inert). As a requirem...
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Liquid chromatography–mass spectrometry Tal'roze and collaborators started the development of LC-MS in the early 1970s, when they first used capillaries to connect LC columns and MS ion sources. A similar strategy was investigated by McLafferty and collaborators in 1973. This was the first and most obvious way of coupl...
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Liquid chromatography–mass spectrometry After removing the liquid phase, the analytes would desorb from the belt and migrate to the MS ion source to be analysed. MBI was successfully used for LC-MS applications between 1978 and 1990 because it allowed coupling of LC to MS devices using EI, CI, and fast-atom bombardment...
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Liquid chromatography–mass spectrometry To use this interface, it was necessary to split the flow coming out of the LC column because only a small portion of the effluent (10 to 50 μl/min out of 1 ml/min) could be analyzed on-line without breaking the MS vacuum. One of the main operational problems of the DLI interface...
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Liquid chromatography–mass spectrometry TSP was also more suitable for LC-MS applications involving reversed phase liquid chromatography (RT-LC). The TSP system had a dual function acting as an interface and a solvent-mediated chemical ionization source. With time, the mechanical complexity of TSP was simplified, and t...
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Liquid chromatography–mass spectrometry In order to be used in FAB MS ionization sources, the analytes of interest should be mixed with a matrix (e.g., glycerol) that could be added before or after the separation in the LC column. FAB based interfaces were extensively used to characterize peptides, but lost applicabili...
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Liquid chromatography–mass spectrometry The components of the mixture are separated depending on their chemical affinity with the mobile and stationary phases. The separation occurs after repeated sorption and desorption steps occurring when the liquid interacts with the stationary bed. The liquid solvent (mobile phase...
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Liquid chromatography–mass spectrometry 7 μm diameter) and requires higher operating pressures in the range of 310.000 to 775.000 torr (6000 to 15000 psi). Mass spectrometry (MS) is an analytical technique that measures the mass-to-charge ratio ("m/z)" of charged particles (ions). Although there are many different kind...
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Liquid chromatography–mass spectrometry MS is an experiment that must take place in gas phase and under vacuum (1.33 * 10 to 1.33 * 10 pascal). Therefore, the development of devices facilitating the transition from samples at higher pressure and in condensed phase (solid or liquid) into a vacuum system has been essenti...
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