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Structure of liquids and glasses The presence of non-bridging oxygens lowers the relative number of strong bonds in the material and disrupts the network, decreasing the viscosity of the melt and lowering the melting temperature. The alkali metal ions are small and mobile; their presence in a glass allows a degree of electrical conductivity. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with their two positive charges and requirement for two non-bridging oxygen ions to compensate for their charge, are much less mobile themselves and hinder diffusion of other ions, especially the alkali's. The most common commercial glass types contain both alkali and alkaline earth ions (usually sodium and calcium), for easier processing and satisfying corrosion resistance. Corrosion resistance of glass can be increased by dealkalization, removal of the alkali ions from the glass surface by reaction with sulphur or fluorine compounds. Presence of alkaline metal ions has also detrimental effect to the loss tangent of the glass, and to its electrical resistance; glass manufactured for electronics (sealing, vacuum tubes, lamps ...) have to take this in account. Silica (the chemical compound SiO) has a number of distinct crystalline forms: quartz, tridymite, cristobalite, and others (including the high pressure polymorphs Stishovite and Coesite). Nearly all of them involve tetrahedral SiO units linked together by "shared vertices" in different arrangements | https://en.wikipedia.org/wiki?curid=30283480 |
Structure of liquids and glasses Si-O bond lengths vary between the different crystal forms. For example, in α-quartz the bond length is 161 pm, whereas in α-tridymite it ranges from 154–171 pm. The Si-O-Si bond angle also varies from 140° in α-tridymite to 144° in α-quartz to 180° in β-tridymite. In amorphous silica (fused quartz), the SiO tetrahedra form a network that does not exhibit any long-range order. However, the tetrahedra themselves represent a high degree of local ordering, i.e. every silicon atom is coordinated by 4 oxygen atoms and the nearest neighbour Si-O bond length exhibits only a narrow distribution throughout the structure. If one consider the atomic network of silica as a mechanical truss, this structure is isostatic, in the sense that the number of constraints acting between the atoms equals the number of degrees of freedom of the latter. According to the rigidity theory, this allows this material to show a great forming ability. Despite the lack of ordering on extended length scales, the tetrahedra also form a network of ring-like structures which lead to ordering on intermediate length scales (up to approximately 10 Angstroms or so). Under the application of high pressure (approximately 40 GPa) silica glass undergoes a continuous polyamorphic phase transition into an octahedral form, i.e. the Si atoms are surrounded by 6 oxygen atoms instead of four in the ambient pressure tetrahedral glass. | https://en.wikipedia.org/wiki?curid=30283480 |
Spectral hole burning is the frequency-selective bleaching of the absorption spectrum of a material, which leads to an increased transmission (a "spectral hole") at the selected frequency. Two basic requirements must be met for the phenomenon to be observed: Most molecules and atoms always return from the excited state to the initial ground state. In some situations, however, this may not happen. For example, some organic dye molecules can undergo a photochemical reaction, which alters the whole chemical structure of the molecule. If such a photochemically active molecule absorbs light, then with a probability of a few percent it will not return to the initial, educt state, but will rather switch over to a new product ground state. Often the homogeneous absorption spectrum of the new product is much different from that of the educt, and the corresponding inhomogeneous bands do not overlap. Spectral hole width can be expressed as follows: where formula_2 is spectral hole width, formula_3 is homogeneous linewidth, formula_4 is the centre frequency and formula_5 is the saturation intensity. | https://en.wikipedia.org/wiki?curid=30285355 |
Galactolysis refers to the catabolism of galactose. In the liver, galactose is converted through the Leloir pathway to glucose 6-phosphate in the following reactions: There are 3 types of galactosemia or galactose deficiencies: | https://en.wikipedia.org/wiki?curid=30290624 |
Parent structure In IUPAC nomenclature, a parent structure, parent compound, parent name, or simply parent is the denotation for a compound consisting of an unbranched chain of skeletal atoms (not necessarily carbon), or consisting of an unsubstituted monocyclic or polycyclic ring system. Parent structures bearing one or more functional groups that are not specifically denoted by a suffix are called functional parents. Names of parent structures are used in IUPAC nomenclature as basis for systematic names. A parent hydride is a "parent structure" with one or more hydrogen atoms. Parent hydrides have a defined standard population of hydrogen atoms attached to a skeletal structure. Parent hydrides are used extensively in organic nomenclature, but are also used in inorganic chemistry. To construct a systematic name, affixes are attached to the parent name, which denote substituents that replace hydrogen. | https://en.wikipedia.org/wiki?curid=30294670 |
C14H12N2O2 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=30295004 |
Rabi resonance method is a technique developed by Isidor Isaac Rabi for measuring the nuclear spin. The atom is placed in a static magnetic field and a perpendicular rotating magnetic field. We present a classical treatment in here. When only the static magnetic field (B) is turned on, the spin will precess around it with Larmor frequency ν and the corresponding angular frequency is ω. According to mechanics, the equation of motion of the spin J is: where μ is the magnetic moment. g is g-factor, which is dimensionless and reflecting the environmental effect on the spin. Solving gives the angular frequency (Larmor frequency) with the magnetic field pointing on z-axis: The minus sign is necessary. It reflects that the J is rotating in left-hand when the thumb is pointing as the H field. when turned on the rotating magnetic field (B), with angular frequency ω. In the rotating frame of the rotating field, the equation of motion is: or if formula_6, the static field was cancelled, and only the "sleeping" rotation frame. and the spin is now precess around H with angular frequency Rabi frequency Since the rotating field is perpendicular to the static field. the spin in rotating frame is now able to flip between up and down. by sweeping ω, one can obtain a maximum flipping and determine the magnetic moment. The experiment setup contains 3 parts: an inhomogeneous magnetic field in front, the rotating field at the middle, and another inhomogeneous magnetic field at the end | https://en.wikipedia.org/wiki?curid=30304860 |
Rabi resonance method Atoms after passing the first inhomogeneous field will split into 2 beams corresponding the spin up and spin down state. Select one beam (spin up state, for example) and let it pass the rotating field. If the rotating field has frequency (ω) equal to the Larmor frequency, it will produce a high intensity of the other beam (spin down state). By sweeping the frequency to obtain a maximum intensity, one can find out the Larmor frequency and the magnetic moment of the atom. http://www.colorado.edu/physics/phys7550/phys7550_sp07/extras/Ramsey90_RMP.pdf | https://en.wikipedia.org/wiki?curid=30304860 |
C8H16O6 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=30308308 |
White box system A white box system is a mechanical system installed in the engine room of a ship for controlling and monitoring the engine room bilge water discharge from the vessel. The system consists of all vital components for monitoring and controlling the discharge from the vessel's oily water separator. The white box includes a stainless steel cage with a locked door. The bilge water from the oily water separator is pumped through the white box and analyzed by an oil content meter. A flow switch secures that there is flow through the oil content meter and a flow meter counts the accumulated discharged overboard volume. If the door is opened, the oil content exceeds the legal limit of 15 parts per million (PPM) or the flow to the oil content meter is lost the three way valve will immediately redirect the bilge water back to the bilge water holding tank. All components inside the system are connected to a digital recorder mounted in the engine control room that records the oil content, three way valve position, flow through oil content meter, accumulated discharged volume, door position together with the vessels geographical position and time. The chief engineer possesses the key and when locked, the system cannot be tampered with and equally importantly provides the evidence that the vessel has been compliant | https://en.wikipedia.org/wiki?curid=30313801 |
White box system The recorder data is stored in an encrypted format and can be presented to any official body such as Port State Control, United States Coast Guard, Vetting or Classification society officials to prove that the vessel has been compliant to MARPOL 73/78 (the International Convention for the Prevention of Pollution From Ships) or any national regulation, and that no illegal discharge has been made. | https://en.wikipedia.org/wiki?curid=30313801 |
Transient kinetic isotope fractionation Transient kinetic isotope effects (or fractionation) occur when the reaction leading to isotope fractionation does not follow pure first-order kinetics and therefore isotopic effects cannot be described with the classical equilibrium fractionation equations or with steady-state kinetic fractionation equations (also known as the Rayleigh equation). In these instances, the general equations for biochemical isotope kinetics (GEBIK) and the general equations for biochemical isotope fractionation (GEBIF) can be used. The GEBIK and GEBIF equations are the most generalized approach to describe isotopic effects in any chemical, catalytic reaction and biochemical reactions because they can describe isotopic effects in equilibrium reactions, kinetic chemical reactions and kinetic biochemical reactions. In the latter two cases, they can describe both stationary and non-stationary fractionation (i.e., variable and inverse fractionation). In general, isotopic effects depend on the number of reactants and on the number of combinations resulting from the number of substitutions in all reactants and products. Describing with accuracy isotopic effects, however, depends also on the specific rate law used to describe the chemical or biochemical reaction that produces isotopic effects. Normally, regardless of whether a reaction is purely chemical or whether it involves some enzyme of biological nature, the equations used to describe isotopic effects base on first-order kinetics | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation This approach systematically leads to isotopic effects that can be described by means of the Rayleigh equation. In this case, isotopic effects will always be expressed as a constant, hence will not be able to describe isotopic effects in reactions where fractionation and enrichment are variable or inverse during the course of a reaction. Most chemical reactions do not follow first-order kinetics; neither biochemical reactions can normally be described with first-order kinetics. To properly describe isotopic effects in chemical or biochemical reactions, different approaches must be employed such as the use of Michaelis–Menten reaction order (for chemical reactions) or coupled Michaelis–Menten and Monod reaction orders (for biochemical reactions). However, conversely to Michaelis–Menten kinetics, GEBIK and GEBIF equations are solved under the hypothesis of non-steady state. This characteristic allows GEBIK and GEBIF to capture "transient" isotopic effects. The GEBIK and GEBIF equations are introduced here below. The GEBIK and GEBIF equations describe the dynamics of the following state variables Both S and P contain at least one isotopic expression of a tracer atom. For instance, if the carbon element is used as a tracer, both S and P contain at least one C atom, which may appear as <chem>^{12}C</chem> and <chem>^{13}C</chem>. The isotopic expression within a molecule is where formula_2 is the number of tracer atoms within S, while formula_3 is the number of isotopic substitutions in the same molecule | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation The condition formula_4 must be satisfied. For example, the <chem>N2</chem> product in which 1 isotopic substitution occurs (e.g., <chem>^{15}N^{14}N</chem>) will be described by <chem>^1_2P</chem>. Substrates and products appear in a chemical reaction with specific stoichiometric coefficients. When chemical reactions comprise combinations of reactants and products with various isotopic expressions, the stoichiometric coefficients are functions of the isotope substitution number. If formula_5 and formula_6 are the stoichiometric coefficient for formula_1 substrate and formula_8 product, a reaction takes the form For example, in the reaction <chem>{^{14}NO3^-} + ^{15}NO3^- -> {^{14}{N}}{^{15}{NO}}</chem>, the notation is <chem>{^0_1S} + {^1_1S} -> {^1_2P}</chem> with formula_10 for both isotopologue reactants of the same substrate with substitution number formula_11 and formula_12, and with formula_13 for <chem>^1_2P</chem> and formula_14 because the reaction does not comprise production of <chem>^0_2P = {^{14}N2O}</chem> and <chem>^2_2P = {^{15}N2O}</chem>. For isotopomers, the substitution location is taken into account as formula_15 and formula_16, where formula_17 and formula_18 indicate a different expressions of the same isotopologue formula_1. Isotopomers only exist when formula_20. The substitution location has to be specifically defined depending on the number of tracer atoms , number of substitutions , and molecule structure | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation For multiatomic molecules that are symmetric with respect to tracer position, there is no need to specify the substitution position when formula_12. For example, one substitution of deuterium <chem>D\ =\ {^2H}</chem> in the symmetric methane molecule <chem>CDH3</chem> does not require the use of the right superscript. In the case that formula_22, the substitution location has to be specified, while for <chem>CHD3</chem> and <chem>CD4</chem> it is not required. For example, two D substitutions in <chem>CD2H2</chem> can occur in adjacent or non-adjacent locations. Using this notation, the reaction <chem>{CD2H2} + {2O2} -> {H2O} + {D2O} + {CO2},</chem> can be written as where formula_17 in <chem>{^2_4S}^{\beta}</chem> defines only one of the two methane forms (either with adjacent or non-adjacent D atoms). The location of D in the two isotopologue water molecules produced on the right-hand side of the reaction has not been indicated because D is present in only one water molecule at saturation, and because the water molecule is symmetric. For asymmetric and multiatomic molecules with formula_24, definition of the substitution location is always required. For instance, the isotopomers of the (asymmetric) nitrous oxide molecule <chem>N2O</chem> are <chem>^1_2S^\beta= {^{15}N}{^{14}NO}</chem> and <chem>^1_2S^\gamma= {^{14}N}{^{15}NO}</chem>. Reactions of asymmetric isotopomers can be written using the partitioning coefficient as where formula_26 | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation For example, using N isotope tracers, the isotopomer reactions can be written as one reaction in which each isotopomer product is multiplied by its partition coefficient as with formula_27. More generally, the tracer element does not necessarily occur in only one substrate and one product. If formula_28 substrates react releasing formula_29 products, each having an isotopic expression of the tracer element, then the generalized reaction notation is For instance, consider the <chem>^{16}O</chem> and <chem>^{18}O</chem> tracers in the reaction In this case the reaction can be written as with two substrates and two products without indication of the substitution location because all molecules are symmetric. Biochemical kinetic reactions of type () are often catalytic reactions in which one or more substrates, formula_30, bind to an enzyme, E, to form a reversible activated complex, C, which releases one or more products, formula_31, and free, unchanged enzyme. These reactions belong to the type of reactions that can be described by Michaelis-Menten kinetics. Using this approach for substrate and product isotopologue and isotopomer expressions, and under the prescribed stoichiometric relationships among them, leads to the general reactions of the Michaelis-Menten type with the index formula_32, where depends on the number of possible atomic combinations among all isotopologues and isotopomers. Here, formula_33, formula_34, and formula_35 are the rate constants indexed for each of the "m" reactions | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation The reactions can be written as The following isotope mass balances must hold To solve for the concentration of all components appearing in any general biochemical reaction as in (), the Michaelis-Menten kinetics for an enzymatic reaction are coupled with the Monod kinetics for biomass dynamics. The most general case is to assume that the enzyme concentration is proportional to the biomass concentration and that the reaction is not in quasi-steady state. These hypotheses lead to the following system of equations \ce S^{\beta_j}_j]}{\ce{d}t} = \sum_i \ce P^{\gamma_h}_h]}{\ce{d}t} = with formula_32, and where formula_39 is the concentration of the most limiting substrate in each reaction "i", z is the enzyme yield coefficient, Y is the yield coefficient expressing the biomass gain per unit of released product and formula_40 is the biomass mortality rate. The isotopic composition of the components in a biochemical system can be defined in different ways depending on the definition of isotopic ratio. Three definitions are described here: Isotopic ratio relative to each component in the system, each with its isotopic expression, with respect to the concentration of its most abundant isotopologue Isotopic ratio relative to the mass of the tracer element in each component; where, formula_45 and formula_46 are the molecular weight of each isotopic expression of the substrate and product | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation Isotopic ratio relative to the mass of the tracer element in the accumulated substrates and products Regardless of the definition of the isotopic ratio, the isotopic composition of substrate and product are expressed as where formula_49 is a standard isotopic ration. Here, definition 3 of isotopic ratio has been used, however, any of the three definitions of isotopic ratio can equally be used. The isotopic ratio of the product can be used to define the instantaneous isotopic ratio and the time-dependent fractionation factor The time-dependent isotopic enrichment is simply defined as Under specific assumptions, the GEBIK and GEBIF equations become equivalent to the equation for steady-state kinetic isotope fractionation in both chemical and biochemical reactions. Here two mathematical treatments are proposed: (i) under biomass-free and enzyme-invariant (BFEI) hypothesis and (ii) under quasi-steady-state (QSS) hypothesis. In instances where the biomass and enzyme concentrations are not appreciably changing in time, we can assume that biomass dynamics is negligible and that the total enzyme concentration is constant, and the GEBIK equations become Eqs. () for isotopic compositions, Eq. () for the fractionation factor and Eq. () for the enrichment factor equally applies to the GEBIK equations under the BFEI hypothesis | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation If the quasi-steady-state hypothesis is assumed in addition to BFEI hypothesis, then the complex concentration can be assumed to be in a stationary (steady) state according to the Briggs-Haldane hypothesis, and the GEBIK equations become \ce P^{\gamma_h}_h ]}{\ce{d}t} \simeq \sum_{i=1}^m \frac{ u_{\gamma_{hi}} y_{d_{hi}} {k}_{3(i)} E_0 \overline{S}_i }{ \overline{S}_i + K_i \left( which are written in a form similar to the classical Micaelis-Menten equations for any substrate and product. Here, the equations also show that the various isotopologue and isotopomer substrates appear as competing species. Eqs. () for isotopic compositions, Eq. () for the fractionation factor and Eq. () for the enrichment factor equally applies to the GEBIK equations under the BFEI and QSS hypothesis. An example is shown where GEBIK and GEBIF equations are used to describe the isotopic reactions of <chem>N2O</chem> consumption into <chem>N2</chem> according to the simultaneous set of reactions These can be rewritten using the notation introduced before as. The substrate <chem>^2_2S\ =\ {^{15}N2O}</chem> has not been included due to its scarcity. In addition, we have not specified the isotopic substitution in the <chem>N2</chem> product of the second and third reactions because <chem>N2</chem> is symmetric | https://en.wikipedia.org/wiki?curid=30320859 |
Transient kinetic isotope fractionation Assuming that the second and third reactions have identical reaction rates formula_50, formula_51, and formula_52, the full GEBIK and GEBIF equations are The same reaction can be described with the GEBIK and GEBIF equations under the BFEI and QSS approximations as where <chem>K3</chem> has been substituted with <chem>K2</chem> because the rate constants in the third reaction have been assumed to equal those of the second reaction. | https://en.wikipedia.org/wiki?curid=30320859 |
Telomerization (dimerization) The telomerization is the linear dimerization of 1,3-dienes with simultaneous addition of a nucleophile in a catalytic reaction. The reaction was independently discovered by E. J. Smutny at Shell and Takahashi at the Osaka University in the late sixties. The general reaction equation is as follows: The formation of several isomers are possible. In addition to 1,3-butadiene also substituted dienes such as isoprene or cyclic dienes such as cyclopentadiene can be used. A variety of substances such as water, ammonia, alcohols, or C-H-acidic compounds can be used as nucleophiles. When water is used, for example di-unsaturated alcohols are obtained. The catalysts used are mainly metal-organic palladium and nickel compounds. In 1991, Kuraray implemented the production of 1-octanol on an industrial scale (5000 t a(-1)). The commercial route to produce 1-octene based on butadiene as developed by Dow Chemical came on stream in Tarragona in 2008. The telomerization of butadiene with methanol in the presence of a palladium catalyst yields 1-methoxy-2,7-octadiene, which is fully hydrogenated to 1-methoxyoctane in the next step. Subsequent cracking of 1-methoxyoctane gives 1-octene and methanol for recycle. While the reaction is catalyzed by Pd(0) complexes, the pre-catalyst can also be a Pd(II) compound that is reduced in situ. Once the Pd(0) catalyst is formed it can coordinate two butadienes which by oxidative coupling give the intermediate B | https://en.wikipedia.org/wiki?curid=30324812 |
Telomerization (dimerization) Even though the oxidative coupling is facile it is nonetheless reversible; the latter is illustrated by the fact that B is only stable at high butadiene concentration. Subsequent protonation of this intermediate by NuH at the 6-position of the η-,η-octadienyl ligand leads to intermediate C. Nw direct attack of the nucleophile can take place at either the 1- or 3-position of the η-octadienyl chain, which leads to the linear or branched product complexes D and D respectively. Upon displacement by new 1,3-butadiene the product telomer is liberated while the catalyst is regenerated and can continue the cycle. While from purely steric reasons nucleophilic attack at the less substituted side of the allyl is favored, the regioselectivity of nucleophilic attack can heavily depend on the exact nature of ligands positioned trans to the allyl group. | https://en.wikipedia.org/wiki?curid=30324812 |
Sodium tungsten bronze is a form of insertion compound with the formula NaWO, where "x" is equal to or less than 1. Named due to its metallic lustre, its electrical properties range from semiconducting to metallic depending on the concentration of sodium ions present; it can also exhibit superconductivity. Prepared in 1823 by the chemist Friedrich Wöhler, sodium tungsten bronze was the first alkali metal bronze to be discovered. They owe some of their properties to the relative stability of the tungsten(V) cation that is formed. A similar family of molybdenum bronzes may have been discovered in 1885 by Alfred Stavenhagen and E. Engels, but they are formed in a very narrow range of temperatures and were not reported again until the 1960s. Sodium tungsten bronze, like other tungsten bronzes, is resistant to chemical reaction under both acidic and basic conditions. Colour is dependent upon the proportion of sodium in the compound, ranging from golden at "x"≈0.9, through red, orange and deep purple, to blue-black when "x"≈0.3. The electrical resistivity of the bronze depends on the proportion of sodium in the compound, with specific resistances of 1.66 mΩ being measured for some samples. It has been suggested that electrons, released when the sodium atoms are ionised, are conducted readily through the tungsten t and oxygen π orbitals. This can be observed in the XPS and UPS spectra: the peak representing the tungsten 5"d" band becomes more intense as "x" rises. For values of "x" below 0 | https://en.wikipedia.org/wiki?curid=30325091 |
Sodium tungsten bronze 3, the bronze is semiconducting rather than metallic. When cooled sufficiently, sodium tungsten bronze becomes a superconductor, with the critical temperature ("T") for NaWO being approximately 2.2 kelvin. The first record of superconductivity in a tungsten bronze was in 1964, with a "T" of 0.57 K. When "x"=1, sodium tungsten bronze adopts a cubic phase: the perovskite crystal structure. In this form, the structure consists of corner-sharing WO octahedra with sodium ions in the interstitial gaps. For "x" values between 0.9 and 0.3, the structure remains similar but with an increasing deficiency of sodium ions and a smaller lattice parameter. A number of other structure types can also be adopted, with varying electrical properties: cubic, tetragonal I and hexagonal phases are metallic, whereas orthorhombic and tetragonal II structures are semiconducting. Wöhler's 1823 synthesis involved reducing sodium tungstate and tungsten trioxide with hydrogen gas at red heat. A more modern approach reduces a melt of the reactants with electricity rather than with hydrogen. Microwave synthesis is also possible, using tungsten powder as the reducing agent. Hydrothermal (both batch and flow) syntheses are also possible. The sodium in this compound can be replaced by other alkali metals to form their tungsten bronzes, and by other metals such as tin and lead. Molybdenum bronzes also exist but are less stable than their tungsten counterparts. | https://en.wikipedia.org/wiki?curid=30325091 |
Kuguaglycoside A kuguaglycoside is one of several chemical compounds (cucurbitane triterpenoid glycosides) isolated from the roots of the bitter melon vine ("Momordica charantia", "kǔguā" in Chinese) by J.-C. Chen and others. Kuguaglycosides are glycosides of triterpene derivatives, with the cucurbitane skeleton. They are colorless solids, soluble in methanol, ethyl acetate, and butanol. They include: B is also found in the fruit of "M. charantia". | https://en.wikipedia.org/wiki?curid=30330743 |
Kuguacin A kuguacin is one of several chemical compounds isolated from the bitter melon vine ("Momordica charantia", "kǔguā" in Chinese) by J.-C. Chen and others. Kuguacins are cucurbitacins, formally derived from the triterpene hydrocarbon cucurbitane. They include: Kuguacins F-S can be extracted with ethanol from the stems and leaves of "M. charantia". Kuguacins I, J, and Q are artifacts of the extraction process. R is obtained as mixture of two epimers. In this process one also obtains momordicine I, kuguacin E, 5β,19-epoxycucurbita-6,23-diene-3β,19,25-triol, karavilagenin D, 3β,7β,25-trihydroxycucurbita-5,(23E)-dien-19-al, and 3β,7β-dihydroxy-25-methoxycucurbita-5,(23E)-dien-19-al In vitro tests showed weak anti-HIV activity for kuguacins F-S, especially kuguacin Q and kuguacin S. | https://en.wikipedia.org/wiki?curid=30332600 |
Methylene (compound) Methylene (systematically named methylidene and dihydridocarbon; also called carbene) is an organic compound with the chemical formula (also written ). It is a colourless gas that fluoresces in the mid-infrared range, and only persists in dilution, or as an adduct. Methylene is the simplest carbene. It is usually detected only at very low pressures, very low temperatures, or as a short-lived intermediate in chemical reactions. The trivial name "carbene" is the preferred IUPAC name. The systematic names "methylidene" and "dihydridocarbon", valid IUPAC names, are constructed according to the substitutive and additive nomenclatures, respectively. "Methylidene" is viewed as methane with two hydrogen atoms removed. By default, this name pays no regard to the radicality of the methylene. Although in a context where the radicality is considered, it can also name the non-radical excited state, whereas the radical ground state with two unpaired electrons is named "methanediyl". "Methylene" is also used as the trivial name for the substituent groups "methanediyl" (), and "methylidene" (). "Methylene" has an electron affinity of 0.65 eV The compound was first detected and studied around 1960, by infrared spectroscopy in frozen gas matrix isolation experiments. Methylene can be prepared, under suitable conditions, by decomposition of compounds with a methylidene or methanediyl group, such as ketene (ethenone) (=CO), diazomethane (linear =), diazirine (cyclic [--N=N-]) and diiodomethane (I--I) | https://en.wikipedia.org/wiki?curid=30333000 |
Methylene (compound) The decomposition can be effected by photolysis, photosensitized reagents (such as benzophenone), or thermal decomposition. Many of methylene's electronic states lie relatively close to each other, giving rise to varying degrees of radical chemistry. The ground state is a triplet radical with two unpaired electrons ("X"̃"B"), and the first excited state is a singlet non-radical ("ã""A"). With the singlet non-radical only 38 kJ above the ground state, a sample of methylene exists as a mixture of electronic states even at room temperature, giving rise to complex reactions. For example, reactions of the triplet radical with non-radical species generally involves abstraction, whereas reactions of the singlet non-radical not only involves abstraction, but also insertion or addition. The singlet state is also more sterospecific than the triplet. Unsolvated methylene will spontaneously autopolymerise to form various excited oligomers, the simplest of which, is the excited form of the alkene ethylene. The excited oligomers, decompose rather than decay to a ground state. For example, the excited form of ethylene decomposes to acetylene and atomic hydrogen. Unsolvated, excited methylene will form stable ground state oligomers. The ground state of methylene has an ionisation energy of 10.396 eV. It has a bent configuration, with H-C-H angle of 133.84°, and is thus paramagnetic. (The correct prediction of this angle was an early success of ab initio quantum chemistry | https://en.wikipedia.org/wiki?curid=30333000 |
Methylene (compound) ) However conversion to a linear configuration requires only 5.5 kcal/mol. The singlet state has a slightly higher energy (by about 9 kcal/mol) than the triplet state, and its H-C-H angle is smaller, about 102°. In dilute mixtures with an inert gas, the two states will convert to each other until reaching an equilibrium. Neutral methylene complexes undergo different chemical reactions depending on the pi character of the coordinate bond to the carbon centre. A weak contribution, such as in diazomethane, yields mainly substitution reactions, whereas a strong contribution, such as in ethenone, yields mainly addition reactions. Upon treatment with a standard base, complexes with a weak contribution convert to a metal methoxide. With strong acids (e.g., fluorosulfuric acid), they can be protonated to give . Oxidation of these complexes yields formaldehyde, and reduction yields methane. Free methylene undergoes the typical chemical reactions of a carbene. Addition reactions are very fast and exothermic. When the methylene molecule is in its state of lowest energy, the unpaired valence electrons are in separate atomic orbitals with independent spins, a configuration known as triplet state. Methylene may gain an electron yielding a monovalent anion methanidyl (), which can be obtained as the trimethylammonium (()) salt by the reaction of phenyl sodium () with trimethylammonium bromide (()). The ion has bent bent geometry, with a H-C-H angle of about 103° | https://en.wikipedia.org/wiki?curid=30333000 |
Methylene (compound) Methylene is also a common ligand in coordination compounds, such as copper methylene . Methylene can bond as a terminal ligand, which is called "methylidene", or as a bridging ligand, which is called "methanediyl". | https://en.wikipedia.org/wiki?curid=30333000 |
C30H50O5 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=30335885 |
C30H50O4 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=30336241 |
Pyrolysis gasoline or Pygas is a naphtha-range product with a high aromatics content. It is a by-product of high temperature naphtha cracking during ethylene and propylene production. Also, it is a high octane number mixture which contains aromatics, olefins and paraffins ranging from C5s to C12s. PyGas has high potential for use as a gasoline blending mixture and/or as a source of aromatics. Currently, PyGas is generally used as a gasoline blending mixture due to its high octane number. Depending on the feedstock used to produce the olefins, steam cracking can produce a benzene-rich liquid by-product called pyrolysis gasoline. can be blended with other hydrocarbons as a gasoline additive, or distilled (in BTX process) to separate it into its components, including benzene. Raw Pyrolysis Gasoline, RPG or Raw Pygas is unhydrogenated Pygas which is rich in Benzene. Hydrogenated Pyrolysis Gasoline, HPG or Hydrogenated Pygas is a feedstock of BTX plant for Benzene and Toluene Extraction. | https://en.wikipedia.org/wiki?curid=30336457 |
C31H52O4 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=30336573 |
Momordicine A momordicine is any of several compounds found in the bitter melon vine, "Momordica charantia". They are glycosides of cucurbitane derivatives. They include II and IV can be extracted from the leaves of "M. charantia" by methanol. They have been found to deter egg-laying of the leaf mining fly ("Liriomyza trifolii") at a combined concentration of 96 µg/cm2. | https://en.wikipedia.org/wiki?curid=30344639 |
AREsite is a database of AU-rich elements (ARE) in vertebrate mRNA 3'-untranslated regions (UTRs). AU-rich elements are involved in the control of gene expression. They are the most common determinant of RNA stability in mammalian cells. | https://en.wikipedia.org/wiki?curid=30351807 |
AspicDB ASPicDB is a database of human protein variants generated by alternative splicing, a process by which the exons of the RNA produced by transcription of a gene are reconnected in multiple ways during RNA splicing. | https://en.wikipedia.org/wiki?curid=30351997 |
Bodo Linnhoff Professor (born 1948) is a chemical engineer and academic who developed pinch analysis, a technique for minimizing energy usage in the process industries. In its early days, the technique helped companies such as ICI and BASF to design plants that used roughly 30% less energy. As of the 1990s, Pinch Analysis became industrial standard in the oil refining and petrochemical industries. In 2010, Linnhoff founded a finance company, Harvester International, which nurtures innovation and guides smaller companies, such as Inview Technology. Born in Berlin, Germany, Linnhoff studied at Technical University of Hannover, Germany and ETH Zurich, Switzerland (MSc in mechanical engineering). He taught at ETH until 1974 when he went to University of Leeds, UK, as a British Council Scholar. There he gained a PhD in chemical engineering (1979). He joined the company ICI in 1977 and moved to the University of Manchester Institute of Science and Technology (UMIST) in 1982 where he was appointed to a Chair in chemical engineering. The key concepts of Pinch analysis were developed in his MSc. dissertation (1972, ETH Zurich) and in his PhD thesis "Thermodynamic Analysis in the Design of Process Networks" (awarded 1979, Leeds University). For this early work, Linnhoff received the Georg-Fischer-Preis of the ETH (1972) and the IChemE (UK) Moulton Medal and “Best Paper” Awards (both in 1980). His work was developed in a series of papers beginning in 1978. Although he and his PhD supervisor John R | https://en.wikipedia.org/wiki?curid=30354275 |
Bodo Linnhoff Flower had difficulty getting the first paper accepted, it became one of the most highly cited in the history of chemical engineering. In ICI, six design optimisation projects in six ICI Divisions (incl USA, Europe and Australia) resulted in significant energy savings. Subsequent programme of method development and further applications followed with ICI itself adopting the technique and further papers followed. Linnhoff led the multi-author team which produced the IChemE User Guide on Process Integration for the Efficient Use of Energy, 1st edition, in 1982. This became the main textbook on pinch analysis, selling well for many years, and formed the backbone of the revised and expanded second edition of 2006, "Pinch Analysis and Process Integration". In 1982 the work was recognised by the award of a Royal Society Gold Medal: the "Esso Energy Award" (UK) "for the contribution to the design of process plants and their energy utilization". The early papers and awards led to sufficient academic status for his appointment to a Chair of Chemical Engineering at UMIST at age 33. Once at UMIST, he established the “Research Consortium” of Internationals (Shell, Exxon, BP, BASF, were founder members) to fund and direct research programmes. He introduced Integrated Process Design, or "Process Integration", as a discipline to Chemical Engineering. In 1983, his team formed the "Centre for Process Integration" at UMIST | https://en.wikipedia.org/wiki?curid=30354275 |
Bodo Linnhoff By 1986, the UMIST "Process Integration Research Consortium" counted member companies from 14 countries from America, Europe and Asia. The "Consortium" promoted technical co-operation between the sponsor companies and the UMIST team. At the time (1980s), consortia of this type were unusual and Linnhoff won a national D.T.I. (Department of Trade and Industry) competition for the best collaborative project between university and industry (1986). Linnhoff established Linnhoff March Ltd. in 1983 and ran it in parallel with UMIST. Linnhoff March offered process design services to international clients such as Shell from the outset. In 1986, training and software product lines were added and overseas offices were set up in the US (1986) and in Japan (1990). Around 1990, several projects for government agencies were set up including MITI (Japan), UBA, LFU (Germany), DTI, DoE (UK), EPA, EPRI (United States) and the European Commission to advise on incoming environmental legislation. In 1986 he became a member of the UK government thinktank on energy conservation and an expert witness at the House of Lords on energy savings potential in industry in 1988. Linnhoff ran Linnhoff March and the UMIST Department of Process Integration in parallel until 1994. Around 80% of all the world's largest oil and petrochemical companies had by then become clients or sponsors. Linnhoff left UMIST in 1994 and built up Linnhoff March into a dominant worldwide supplier | https://en.wikipedia.org/wiki?curid=30354275 |
Bodo Linnhoff He sold the company in 2002 to KBC Advanced Technologies (FTSE listed) and retired. In May 2010, Linnhoff became Chairman of Harvester Capital Ltd. Harvester Capital Ltd. which nurtures small technology companies, helping them to roll out internationally. One such company is Inview Technology which is involved in the Digital television transition of Nigeria from analogue to digital. | https://en.wikipedia.org/wiki?curid=30354275 |
BRENDA tissue ontology The BTO (BRENDA Tissue Ontology) represents a comprehensive structured encyclopedia. It provides terms, classifications, and definitions of tissues, organs, anatomical structures, plant parts, cell cultures, cell types, and cell lines of organisms from all taxonomic groups (animals, plants, fungis, protozoon) as enzyme sources. The information is connected to the functional data in the BRENDA ("BRaunschweig ENzyme DAtabase“) enzyme information system. BTO is one of the first tissue-specific ontologies in life sciences, not restricted to a specific organism or a specific organism group providing a user-friendly access to the wide range of tissue and cell-type information. Databases, such as "Ontology Lookup Service" or ses, such as "MIRIAM Registry" or of the EBI-EMBL, the "TissueDistributionDB", including the "Tissue Synonym Library" of the German Cancer Research Center (DKFZ) in Heidelberg or the "Bioportal" plattform of the National Center for Biomedical Ontology in Stanford, USA rely on BTO and implement the encyclopedia as an essential repository of information into their respective plattform. BTO enables users from medical research and pharmaceutical sciences to search for the occurrence and histological detection of disease-related enzymes in tissues, which play an important role in diagnosis, therapies, and drug development | https://en.wikipedia.org/wiki?curid=30355579 |
BRENDA tissue ontology In biochemistry and biotechnology the organism-specific tissue terms linked to enzyme functional data are an important resource for the understanding of the metabolism and regulation in life sciences. Ontologies represent classification systems that provide controlled and structured vocabularies. They are important tools to illustrate and to link evolutionary correlations. Development of BTO started in 2003, aimed to connect the biochemical and molecular biological enzyme data of BRENDA with a hierarchical and standardized collection of tissue-specific terms. The functional enzyme data and information in BRENDA have been manually annotated and structured by experts from biochemistry, biology, and chemistry. By October 2019, the BTO contained over 6,042 terms, linked to 5,173 synonyms and 5,074 definitions. The terms are classified under generic categories, rules, and formats of the Gene Ontology Consortium (GO,), organized as a directed acyclic graph (DAG) created using the open-source OBO-Edit. All terms from each level are directly connected the enzyme data in BRENDA. BTO is a suitable tool to distinguish between different enzymes which are expressed in a tissue-specific manner. BTO draws upon the comprehensive enzyme specific data of the BRENDA enzyme information system. Presently (October 2019) 112,200 enzyme-organism-tissue specific data from more than 11,000 proteins are stored in BRENDA. These entries were manually annotated from more thant 150,000 different literature references | https://en.wikipedia.org/wiki?curid=30355579 |
BRENDA tissue ontology All terms in BTO are evaluated and classified according to the OBO-format, and are connected by specific relationships. Each term is a distinct entry within the ontology and is automatically assigned to a unique BTO-identifier (BTO-ID). The BTO-IDs serve as stable accession numbers in order to create cross-references to further external biochemical databases. Further tissue und cell-type specific terms from external databases (i.e. UniProt) are integrated into BTO. The terms are classified in 4 main categories (subgraphs): Further levels are defined below the main categories (=nodes), classifying the “parent”, “child”, and “grandchild” all connected via specific relationships (=edges) Most of the terms are clearly associated with specific organisms, organs, tissues, or cell types. However, there are several identical designations for tissues both in plants and animals, e.g. “epidermis”. To distinguish between those tissue terms and to classify them correctly into BTO for plant tissues the prefix “plant” is placed before the term, e.g. “plant epidermis”. More than 80% of the tissue terms have definitions that describe the meaning and context. These definitions are obtained from i.e. medical dictionaries and cell line databases (Webster’s Dictionary, DSMZ). The entries in BTO are updated bi-annually as part of the major update of BRENDA. It is available via the BRENDA website in the category “Ontology Explorer”. The enzyme source terms can be searched via the BTO query form | https://en.wikipedia.org/wiki?curid=30355579 |
BRENDA tissue ontology As a result, the user receives a list of EC numbers which are directly connected to the enzyme information of BRENDA. It is also possible to search via the BRENDA “Source Tissue” search form (“Classic View”). The result page displays all enzymes which are isolated or detected in the searched tissue term, directly linked to BTO. BTO and BRENDA are freely accessible for academic users. It can be freely downloaded via the “Ontology Explorer” of the BRENDA website or in the OBO format from “Obofoundry”. | https://en.wikipedia.org/wiki?curid=30355579 |
ChemProt is a database of annotated and predicted chemical-protein interactions | https://en.wikipedia.org/wiki?curid=30357527 |
CLIPZ is a database of post-transcriptional regulatory elements (RNA-binding proteins) built from cross-linking and immunoprecipitation data. | https://en.wikipedia.org/wiki?curid=30357670 |
Ring (chemistry) In chemistry, a ring is an ambiguous term referring either to a simple cycle of atoms and bonds in a molecule or to a connected set of atoms and bonds in which every atom and bond is a member of a cycle (also called a ring system). A ring system that is a simple cycle is called a monocycle or simple ring, and one that is not a simple cycle is called a polycycle or polycyclic ring system. A simple ring contains the same number of sigma bonds as atoms, and a polycyclic ring system contains more sigma bonds than atoms. A molecule containing one or more rings is called a cyclic compound, and a molecule containing two or more rings (either in the same or different ring systems) is termed a polycyclic compound. A molecule containing no rings is called an acyclic or open-chain compound. A homocycle or homocyclic ring is a ring in which all atoms are of the same chemical element. A heterocycle or heterocyclic ring is a ring containing atoms of at least two different elements, i.e. a non-homocyclic ring. A carbocycle or carbocyclic ring is a homocyclic ring in which all of the atoms are carbon. An important class of carbocycles are alicyclic rings, and an important subclass of these are cycloalkanes. In common usage the terms "ring" and "ring system" are frequently interchanged, with the appropriate definition depending upon context | https://en.wikipedia.org/wiki?curid=30366884 |
Ring (chemistry) Typically a "ring" denotes a simple ring, unless otherwise qualified, as in terms like "polycyclic ring", "fused ring", "spiro ring" and "indole ring", where clearly a polycyclic ring system is intended. Likewise, a "ring system" typically denotes a polycyclic ring system, except in terms like "monocyclic ring system" or "pyridine ring system". To reduce ambiguity, IUPAC's recommendations on organic nomenclature avoid the use of the term "ring" by using phrases such as "monocyclic parent" and "polycyclic ring system". | https://en.wikipedia.org/wiki?curid=30366884 |
DiProDB is a database designed to collect and analyse thermodynamic, structural and other dinucleotide properties. | https://en.wikipedia.org/wiki?curid=30368248 |
Endecaphyllacin is either of two similar compounds found in certain plants, such as "Hemsleya endecaphylla". Endecaphyllacins A and B can be extracted from the dried tubers of "Hemsleya endecaphylla" with methanol, at concentrations 150 mg/72 g and 20 mg/72 g. | https://en.wikipedia.org/wiki?curid=30370350 |
Dicarbollide In organometallic chemistry, a dicarbollide is an anion of the formula [CBH]. Various isomers exist, but most common is 1,2-dicarbollide derived from ortho-carborane. These dianions function as ligands, related to the cyclopentadienyl anion. Substituted dicarbollides are also known such as [CBH(pyridine)] (pyridine bonded to B) and [CRBH] (R groups bonded to carbon). Dicarbollides are obtained by base-degradation of 12-vertex dicarboranes. This degradation of the ortho derivative has been most heavily studied. The conversion is conducted in two-steps, first "deboronation" and second deprotonation: The dianion derived from ortho-carborane, [CBH is a nido cluster. The nomenclature rules call the high coordination number vertex as 1. Thus the nido cluster with two adjacent carbon centers on the rim is the 7,8-isomer. A variety of complexes are known with one or two dicarbollide ligands. An example of a 1:1 complex is [Mn(CO)(η-7,8-CBH)]. Most heavily studied are complexes with two dicarbollide ligands, especially sandwich complexes. Thus, these are prepared by salt metathesis reactions, as illustrated by the synthesis of the ferrocene analogue: These bisdicarbollide dianions are often readily oxidized. Fe(III), Co(III), Ni(III), and Ni(IV) derivatives are known. In some cases, the oxidation induces rearrangement of the CB cage to give complexes where the carbon centers are nonadjacent. | https://en.wikipedia.org/wiki?curid=30370470 |
Genetic codes (database) Genetic codes is a simple ASN.1 database hosted by the National Center for Biotechnology Information and listing all the known Genetic codes. | https://en.wikipedia.org/wiki?curid=30370937 |
Hemslecin is any of several compounds obtained from plants of the genus "Helmseya", which are used in Asian folk medicine. They are triterpene derivatives, specifically with the cucurbitane skeleton, related to cucurbitacin F. The hemslecins include: Hemslecins A and B have antibacterial properties, and have been proven to be effective against infectious diseases such as enteritis, bronchitis, acute tonsillitis, and bacillary dysentery. | https://en.wikipedia.org/wiki?curid=30371398 |
Dissolved gas flotation (DGF) systems are used for a variety of applications throughout the world. The process floats solids, oils and other contaminants to the surface of liquids. Once on the surface these contaminants are skimmed off and removed from the liquids. Oil and gas production facilities have used flotation systems to remove oil and solids from their produced and processed water (wastewater) for many years.The relative density of candle wax is 0.93, hence objects made of wax float on water. The keys to good separation are both gravity and the creation of millions of very small bubbles. Based on Stokes' law, the size of the oil droplet and density of the droplet will affect the rate of rise to the surface. The larger and lighter the droplet, the faster it will rise to the surface. By attaching a small gas bubble to an oil droplet, the density of the droplet decreases, which increases the rate at which it will rise to the surface. Therefore, the smaller the gas bubbles created the smaller the oil droplet floated to the surface. Efficient flotation systems need to create as many small bubbles as possible. The method in which the bubbles are introduced into the water stream and retention time are also important factors. The average retention time for a vertical unit is typically 4 to 5 minutes and 5 to 6 minutes for a horizontal unit. The impeller in a DGF pump is designed with dual sides | https://en.wikipedia.org/wiki?curid=30377575 |
Dissolved gas flotation One side is designed to drive the liquid like a normal centrifugal pump and the other side is designed to draw vapor into the pump and mix it with the liquid. In addition to the new impeller, a special seal was invented to extend the life of the pump. With these innovations the pump creates a sub-atmospheric pressure region within the pump's seal chamber. As the impeller draws in the vapor it is mixed with the liquid being pumped and compressed into micro-fine bubbles. Because of the close tolerance between the backvanes of the impeller and the backplate of the pump the vapor is sheared into fine bubbles and then they are compressed in the sub-atmospheric pressure region of the pump. These fine bubbles become dissolved into the liquid within the volute of the pump. The result of this process provides similar size bubbles to a dissolved air flotation system. The backpressure valve on the discharge piping can regulate the bubble size in a DGF pump. The bubble size ranges from 50 down to 1 micrometer or less. | https://en.wikipedia.org/wiki?curid=30377575 |
Wet nanotechnology (also known as wet nanotech) involves working up to large masses from small ones. requires water in which the process occurs. The process also involves chemists and biologists trying to reach larger scales by putting together individual molecules. While Eric Drexler put forth the idea of nano-assemblers working dry, wet nanotech appears to be the likely first area in which something like a nano-assembler may achieve economic results. Pharmaceuticals and bioscience are central features of most nanotech start-ups. Richard A.L. Jones calls nanotechnology that steals bits of natural nanotechnology and puts them in a synthetic structure "biokleptic nanotechnology". He calls building with synthetic materials according to nature's design principles "biomimetic nanotechnology". Using these guiding principles could lead to trillions of nanotech robots, that resemble bacteria in structural properties, entering a person's blood stream to do medical treatments. is an anticipated new sub-discipline of nanotech that is going to mostly be dominated by the different forms of wet engineering. The processes that will be used are going to take place in aqueous solutions and are very close to that of biotechnology manufacturing / bio-molecular manufacturing which is largely concerned with the production of biomolecules like proteins and DNA/RNA | https://en.wikipedia.org/wiki?curid=30380229 |
Wet nanotechnology There is some overlap of Biotechnology and because living things are inherently bottom-up engineered and any exploitation of this by biotechnologists means they dabble in bottom-up engineering (though mostly at the level of producing macromolecules like proteins and nucleic acids from there monomer units. Wet nanotech, however, seeks to analyse living things and their components as engineering systems and aims to understand them completely to have complete control of the behavior of the system and to derive principles and methods that can be applied more broadly to bottom up manufacturing, to manipulate matter on the atomic and molecular scales and to creating machines or devices at the nanometer and microscopic scales. Biotech is mostly about exploiting living systems in anyway possible. Molecular Biology and related disciplines compare the mechanism of function of proteins in particular - and nucleic acids to a lesser extent - as like "molecular machines". In order for engineers to mimic these nanoscale machines in a way that they could be produced with some efficiency, they must look into bottom-up manufacturing. Bottom-up manufacturing deals with manipulating individual atoms during the manufacturing process, so that there is absolute control of their placement and interactions. Then from the atomic scale, nanomachines could be made and even be designed to self-replicate themselves as long as they are designed in an environment with copious amount of the needed materials | https://en.wikipedia.org/wiki?curid=30380229 |
Wet nanotechnology Because individual atoms are being manipulated in the process, bottom-up manufacturing is often referred to as “atom by atom” manufacturing. If the manufacturing of nanomachines can be made more readily available through improved techniques, there could be a large economic and social impact. This would start with improvements in making microelectromechanical systems and then would allow for the creation of nanoscale biological sensors along with things that have not been thought of yet. This is because “wet” nanotech is only in the beginning of its life. Scientists and engineers alike feel that biomimetics is a great way to start looking at creating nanoscale machines. Humans have only had a few thousand years to try to learn about the mechanics of things at really small scales. However, nature has been working on perfecting the design and functionality of nanomachines for millions of years. This is why there are already nanomachines, such as ATP synthase, working in our bodies that have an unheard of 95% efficiency. is a form of wet engineering as opposed to dry engineering. There are different fields that deal with those two types of engineering. Biologists, from the point of view of nanotechnology, deal with wet engineering. They study processes that happen in life, and for the most part those processes take place in aqueous environments. Our bodies are made up mostly of water. Electrical and mechanical engineers are on the other side of the line in dry engineering | https://en.wikipedia.org/wiki?curid=30380229 |
Wet nanotechnology They are involved with processes and manufacturing that does not occur in aqueous environments. For the most part, wet engineering deals with “soft” materials that allow for flexibility which is vital at the nanoscale in biological manufacturing. Dry engineers mostly handle things with rigid structures and parts. These differences stem for the fact that the forces that the two types of engineers must deal with are very different. At a larger scale, most things are dominated by Newtonian physics. However, when one looks at the nanoscale, especially in biological matters, the dominating force is Brownian motion. Because nanotechnology in the new age is going to most likely deal with both dry and wet in conjunction with each other, there is going to have to be a change in the way society looks at engineering and manufacturing. People will have to be not only well educated in engineering but also in biology because the integration of the two is how there will be the largest improvements in nanotechnology. With the existence of natural nanomachines, “a complex precision microscopic-sized machine that fits the standard definition of a machine”, such as ATP synthase and T4 bacteriophage, scientists and biologists know that they are capable of making similar types of machines at the same scale. However, nature has had a long time to perfect the building and creation of these nanomachines and humankind has only just begun to look into them with greater interest | https://en.wikipedia.org/wiki?curid=30380229 |
Wet nanotechnology This interest may have been sparked because of the existence of nanomachines such as ATP synthase (adenosine triphosphate), which is the “second in importance only to DNA”. ATP is the main energy converter that our bodies contain and without it, life as we know it would not be able to flourish or even survive. Brownian motion is a random, constantly fluctuating force that acts on a body in environments that are at a microscale. This force is one that mechanical engineers and physicists are not used to dealing with because, at the larger scale that humankind tends to think of things, this force is not one that needs to be taken into account. People think of gravity, inertia, and other physics based forces that act on us all the time, however at the nanoscale those forces are mostly “negligible”. In order for nanomachines to be recreated by man, either there will need to be discoveries that allow us to understand how to “exploit” Brownian motion as nature does or find a way to work around it by using materials that are rigid enough to stand up to these forces. The way that nature has been able to exploit Brownian motion is through self-assembly. This force pushes and pulls all of the proteins and amino acids around in our bodies and sticks them together in all sorts of combinations. The combinations that do not work separate and continue with their random attachment however, the combinations that do work produce things like ATP synthase | https://en.wikipedia.org/wiki?curid=30380229 |
Wet nanotechnology Through this process nature has been able to make a nanomachine that is 95% efficient, which is a feat that man has not been able to accomplish yet. This is all because nature does not try to work around the forces; it uses them at its advantage. Growing cells in culture to take advantage of their internal chemical synthesis machinery can be considered a form of nanotechnology but this machinery has also been manipulated outside of living cells. | https://en.wikipedia.org/wiki?curid=30380229 |
Datiscoside is any one of several chemical compounds isolated from certain plants, notably "Datisca glomerata". They can be seen as derivatives of the triterpene hydrocarbon cucurbitane (), more specifically from cucurbitacin F. They include: | https://en.wikipedia.org/wiki?curid=30380875 |
Pseudo palladium (RhAg) is a binary alloy consisting of equal parts of rhodium (atomic number 45) and silver (atomic number 47) created using nanotechnology to create a far more homogeneous mixture than might be possible using more conventional methods. This alloy exhibits properties of the intervening element palladium (atomic number 46). The production of this alloy was first reported by Kyoto University Professor Hiroshi Kitagawa and his research team, October 27, 2010. To make the new alloy, the Kyoto team used nanotechnology to "nebulise" the rhodium and silver and gradually mixed them with heated alcohol, with the two metals mixed stably at the atomic level. The same team also produced alternatives to other kinds of rare metals. The new alloy has similar properties to palladium, which is used as a catalyst to cleanse exhaust gas and absorbs large quantities of hydrogen. Rhodium, palladium and silver have 45, 46 and 47 electrons, respectively, numbers that determine their chemical characterizations. "The orbits of the electrons in the rhodium and silver atoms probably got jumbled up and formed the same orbits as those of palladium," Kitagawa said. The alloy has similar properties to palladium, which is used in cars' emission-reducing catalytic converters as well as in computers, mobile phones, flatscreen TVs and dentistry instruments. Hydrogen storage is cited as one potential use, however, according to researchers, the pseudo palladium alloy has only one half of palladium's hydrogen storage capacity. | https://en.wikipedia.org/wiki?curid=30381248 |
Spinoside is any one of several chemical compounds isolated from certain plants, notably "Desfontainia spinosa". They can be seen as derivatives of the triterpene hydrocarbon cucurbitane (), more specifically from cucurbitacin H. They include | https://en.wikipedia.org/wiki?curid=30381533 |
Bryoamaride is a chemical compound isolated from certain plants, notably "Bryonia dioica". It can be seen as a derivative of the triterpene hydrocarbon cucurbitane (), more specifically from cucurbitacin L or 23,24-dihydrocucurbitacin I. The derivative 25-"O"-acetylbryoamaride is found in "Trichosanthes tricuspidata". | https://en.wikipedia.org/wiki?curid=30381767 |
William Moffitt William E. Moffitt (9 November 1925 – 19 December 1958) was a British quantum chemist. He died after a heart attack following a squash match. He had been thought to be one of Britain’s most gifted academics. Moffitt was born in Berlin, Germany, and was educated by private tuition up to the age of 11. He attended Harrow School from 1936-43. His chemistry master later said of him that “he was undoubtably the most able of a decade of gifted boys ... [and] has a profound effect on all who met him. He did more than anyone to create in the school the intellectual climate so necessary for the stimulation of young minds.” He then studied chemistry at New College, Oxford, under an open scholarship, and graduated with first class honours. His D.Phil. supervisor Coulson later wrote: [his] exuberant delight in life remained with him to the end. “Moffit's method of Atoms in Molecules” will remain for many years to remind us of his remarkable ability to initiate new ways of thinking in his professional subject. After receiving his D.Phil. for research in quantum chemistry, he joined the research staff of the British Rubber Producers Research Association. He was made an Assistant Professor at Harvard in January 1953, and was give an A.M Honoris Causa in 1955. His colleague Edgar Bright Wilson said: Few men had as great an impact at so early an age. The reasons are clear | https://en.wikipedia.org/wiki?curid=30388594 |
William Moffitt Few have been endowed with such a sparkling, quick and keen intelligence, with such a capacity for spending long hours in the thorough study of fundamental subjects ... His intellectual powers were not only applied to the solution of problems but perhaps even more to their wise selection. He avoided areas where only formal solutions were attainable, with no contact with experience. He married Dorothy Silberman in 1956 and had a daughter, Alison in June 1958. He was a keen rugby player and enjoyed music and arts and particularly English literature. While sharing a cabin with a monk on a voyage to the UK from the US, he discussed the philosophy of religion with him in their only common language, Latin. | https://en.wikipedia.org/wiki?curid=30388594 |
KT5720 is a kinase inhibitor with specificity towards protein kinase A. It is a semi-synthetic derivative of K252a and analog of staurosporine. | https://en.wikipedia.org/wiki?curid=30402466 |
Pablo DT Valenzuela (; born June 13, 1941) is a Chilean biochemist dedicated to biotechnology development. He is known for his genetic studies of hepatitis viruses; participated as R&D Director in the discovery of hepatitis C virus and the invention of the world's first recombinant vaccine (against hepatitis B virus). He is one of the cofounders of the biotechnology company Chiron Corporation and of Fundacion Ciencia para la Vida, a private non profit institution where he is currently working. Pablo Valenzuela studied biochemistry at Universidad de Chile and earned his Ph.D. degree (1970) in Chemistry at Northwestern University, did a postdoctoral training at University of California, San Francisco and held a position as Professor in the Biochemistry Department of that institution. In 1981, together with William J. Rutter and Edward Penhoet founded the biotechnology company Chiron Corporation that in 1997 was the second-largest biotechnology company in the world, after Amgen. As Research Director Pablo Valenzuela developed a variety of biotechnological products, specially in the blood banking industry. The invention of the recombinant vaccine against Hepatitis B virus was chosen by Business Week as one of the three most innovative technological products of the year 1986. In Chile Pablo Valenzuela founded Bios Chile, the first biotechnology company in that country, and in 1997 together with Bernardita Mendez he cofounded Fundacion Ciencia Para la Vida a non profit foundation that carries out scientific and technological research | https://en.wikipedia.org/wiki?curid=30407215 |
Pablo DT Valenzuela He is the father of Chilean American singer/songwriter, Francisca Valenzuela. is the scientist responsible for the development of biotechnology products in USA and Chile in the area of international diagnostics, blood banking and pharmaceutical. He is cofounder and responsible of early activities of biotechnology Start-ups in USA and Chile. Pablo Valenzuela is also Professor and Investigator in graduate programs, generating scientific publications and patents. Pablo Valenzuela was recipient of the Chilean National Prize for Applied Sciences and Technologies in 2002 and is a member of the Chilean Academy of Sciences. | https://en.wikipedia.org/wiki?curid=30407215 |
Ambix is a peer-reviewed academic journal on the history of alchemy and chemistry that was established in 1937. It was not published from 1939 to 1945. "Ambix" was one of the first journals of the history of science in the English-speaking world, preceded by "Isis" (1912) and "Annals of Science" (1936). "Ambix" is published four times a year, in February, May, August and November. It is currently published for the Society for the History of Alchemy and Chemistry by Taylor & Francis, which in 2015 purchased Maney Publishing, the previous publisher of Ambix. The name of the journal comes from the Greek word for a still-head (ἄμβιξ), which later gave rise to the word alembic. The papers published in "Ambix" are refereed by an international editorial board. The journal covers a wide variety of topics from any historical period and geographical area, including but not limited to "chrysopoeia", alchemy and religion, alchemy/chemistry and experiments, alchemy/chemistry and society, alchemical medicine, recent chemistry, and chemistry courses. Recently, more attention has been given to the history of alchemy, while continues to provide important reading for historians of chemistry. The presentation of scientific ideas, methods and discoveries is made as non-technical as possible, consistent with academic rigour and scientific accuracy. Extensive book reviews are published in each issue of "Ambix". The Journal has published several special issues on a variety of topics | https://en.wikipedia.org/wiki?curid=30417307 |
Ambix The most recent issue was devoted to new studies on Sir Humphry Davy. The November 2017 issue of "Ambix" celebrates 80 years of the journal, and includes articles by former Editor Jennifer Rampling, Hasok Chang, and the 2017 Partington Prize winning paper written by Steve Irish. Earlier special issues include "The Royal Typographer and the Alchemist: Willem Silvius and John Dee" (2017) and "Chemical Knowledge in Transit" (2015). In May 2013, 2014, and 2015 three special issues were published on Sites of Chemistry devoted to the eighteenth, nineteenth and twentieth centuries respectively, while the November 2014 special issue concerned Analysis and Synthesis in Medieval and Early Modern Europe. | https://en.wikipedia.org/wiki?curid=30417307 |
Beta-Neoendorphin β-Neoendorphin is an endogenous opioid peptide with a nonapeptide structure and the amino acid sequence Tyr-Gly-Gly-Phe-Leu-Arg-Lys-Tyr-Pro. | https://en.wikipedia.org/wiki?curid=30418754 |
Alpha-Neoendorphin α-Neoendorphin is an endogenous opioid peptide with a decapeptide structure and the amino acid sequence Tyr-Gly-Gly-Phe-Leu-Arg-Lys-Tyr-Pro-Lys. α-neoendorphin is a neuropeptide. Prodynorphin or Proenkephalin B is its precursor. Researchers and anatomists have not yet studied the distribution of α-neoendorphin in the human in detail. However, some studies have been done which supports the presence of α-neoendorphin immunoreactive fibers throughout the human brainstem. According to a study done by Duque, Ewing, Arturo Mangas, Pablo Salinas, Zaida Díaz-cabiale, José Narváez, and Rafael Coveñas; α-neoendorphin immunoreactive fibers can be found in the caudal part of the solitary nucleus, in the caudal and the gelatinosa parts of the spinal trigeminal nucleus, and only low density was found in the central grey matter of medulla. | https://en.wikipedia.org/wiki?curid=30419251 |
Interstellar ice consists of grains of volatiles in the ice phase that form in the interstellar medium. Ice and dust grains form the primary material out of which the Solar System was formed. Grains of ice are found in the dense regions of molecular clouds, where new stars are formed. Temperatures in these regions can be as low as , allowing molecules that collide with grains to form an icy mantle. Thereafter, atoms undergo thermal motion across the surface, eventually forming bonds with other atoms. This results in the formation of water and methanol. Indeed, the ices are dominated by water and methanol, as well as ammonia, carbon monoxide and carbon dioxide. Frozen formaldehyde and molecular hydrogen may also be present. Found in lower abundances are nitriles, ketones, esters and carbonyl sulfide. The mantles of interstellar ice grains are generally amorphous, only becoming crystalline in the presence of a star. The composition of interstellar ice can be determined through its infrared spectrum. As starlight passes through a molecular cloud containing ice, molecules in the cloud absorb energy. This adsorption occurs at the characteristic frequencies of vibration of the gas and dust. Ice features in the cloud are relatively prominently in this spectra, and the composition of the ice can be determined by comparison with samples of ice materials on Earth. In the sites directly observable from Earth, around 60–70% of the interstellar ice consists of water, which displays a strong emission at 3 | https://en.wikipedia.org/wiki?curid=30422155 |
Interstellar ice 05 μm from stretching of the O–H bond. In September 2012, NASA scientists reported that polycyclic aromatic hydrocarbons (PAHs), subjected to interstellar medium (ISM) conditions, are transformed, through hydrogenation, oxygenation and hydroxylation, to more complex organics - "a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively". Further, as a result of these transformations, the PAHs lose their spectroscopic signature which could be one of the reasons "for the lack of PAH detection in "interstellar ice grains", particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks." Research published in the journal "Science" estimates that about 30–50% of the water in the solar system, like the water on Earth, the discs around Saturn, and the meteorites of other planets was already around even before the birth of the Sun. On 18 November 2014, spacecraft Philae revealed presence of large amount of water ice on the comet 67P/Churyumov–Gerasimenko, the report stating that "the strength of the ice found under a layer of dust on the first landing site is surprisingly high". The team responsible for the MUPUS (Multi-Purpose Sensors for Surface and Sub-Surface Science) instrument, which hammered a probe into the comet, estimated that the comet is hard as ice | https://en.wikipedia.org/wiki?curid=30422155 |
Interstellar ice "Although the power of the hammer was gradually increased, we were not able to go deep into the surface," explained Tilman Spohn from the DLR Institute for Planetary Research, who led the research team. | https://en.wikipedia.org/wiki?curid=30422155 |
METLIN The Metabolite and Chemical Entity Database is the largest repository of experimental tandem mass spectrometry data acquired from standards. The tandem mass spectrometry information on over 450,000 compounds () is provided to facilitate the identification of chemical entities from tandem mass spectrometry experiments. In addition to identification of known molecules it is also very useful for identifying unknowns using its similarity searching technology. All tandem mass spectrometry data comes from the experimental analysis of standards at multiple collision energies and in both positive and negative ionization modes. serves as a data management system to assist in metabolite and chemical entity identification by providing public access to its repository of comprehensive MS/MS metabolite data. An annotated list of known compounds including metabolites and other chemical entities through their mass, chemical formula, and structure are available on the website. Each molecule is linked to outside resources such as the "Kyoto Encyclopedia of Genes and Genomes" (KEGG) for further reference and inquiry. Available MS/MS data are expanding continuously. The database was developed and is maintained solely by the Siuzdak laboratory at The Scripps Research Institute | https://en.wikipedia.org/wiki?curid=30423939 |
METLIN Since its initial implementation in 2005, the freely available website has collected comments and suggestions for improvements from users in the biotechnology, pharmaceutical and academic communities ultimately resulting in a dynamic, intuitive, and functionally useful metabolomics and chemical identification technology. The improved interface allows researchers to readily search the database and characterize metabolites and other compounds through features such as accurate mass, single and multiple fragment searching, neutral loss and full spectrum search capabilities. The powerful similarity searching is a feature introduced in 2010. These features are designed to facilitate the value of their metabolomics MS and MS/MS data and expedite the identification process of both known and unknown molecules. The database is implemented in the cloud to enable users from all over the world to have access. In addition to enhancements to the data structure, is designed to search tandem mass spectrometry data, precursor mass, chemical formulas, compound names among other search capabilities. The tandem MS high-resolution ESI-QTOF MS/MS data on now over 450,000 distinct chemical entities, includes mass spectral collision-induced dissociation data at four different collision energies, in both positive and negative ionization modes. | https://en.wikipedia.org/wiki?curid=30423939 |
Weyburn-Midale Carbon Dioxide Project The (or IEA GHG Weyburn-Midale Monitoring and Storage Project) is, as of 2008, the world's largest carbon capture and storage project. It is located in Midale, Saskatchewan, Canada. The IEAGHG Weyburn-Midale CO Monitoring and Storage Project is an international collaborative scientific study to assess the technical feasibility of CO storage in geological formations with a focus on oil reservoirs, together with the development of world leading best practices for project implementation. The project itself began in 2000 and runs until the end of 2011 when a best practices manual for the transitioning of CO-EOR operations into long-term storage operations will be released. The research project accesses data from the actual CO-enhanced oil recovery operations in the Weyburn oil field (formerly operated by Cenovus Energy of Calgary before its Saskatchewan operations were sold to Whitecap Resources in 2017), and after the year 2005 from the adjacent Midale field (operated by Apache Canada). These EOR operations are independent of the research program. Cenovus Energy's only contribution to the IEAGHG Weyburn-Midale CO Monitoring and Storage Project was to allow access to the fields for measurement, monitoring and verification of the CO for the global scientists and researchers involved in the project. The Weyburn and Midale oil fields were discovered in 1954 near Midale, Saskatchewan. The Weyburn Oilfield covers an area of some and has a current oil production rate of ~3,067 m3/day | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project Original oil-in-place is estimated to be . The oil is produced from a total of 963 active wells made up of 534 vertical wells, 138 horizontal wells, and 171 injection systems. There are also 146 enclosed wells. Current production consists primarily of medium-gravity crude oil with a low gas-to-oil ratio. The Midale oil field is about in size, and has of oil-in-place. It began injecting CO in 2005. Various enhanced oil recovery techniques were used in the Weyburn field prior to the introduction of CO, between the 1970s and 1990s. These include additional vertical drilling, the introduction of horizontal drilling, and the use of waterfloods to increase pressure in the reservoir. In October 2000, Cenovus (formerly Pan Canadian, Encana) began injecting significant amounts of carbon dioxide into the Weyburn field in order to boost oil production. Cenovus was the operator and held the largest share of the 37 current partners in the oilfield prior to the sale of local assets to Whitecap in 2017. Initial CO injection rates in the Weyburn field amounted to ~5,000 tonnes/day or 95 million scf/day (2.7 million m3/d); this would otherwise have been vented to the atmosphere from the Dakota Gasification facility. At one point, CO injection by Cenovus at Weyburn was at ~6,500 tonnes per day. Apache Canada is injecting approximately 1,500 tonnes/day into the Midale field | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project Overall, it is anticipated that some 40 Mt of carbon dioxide will be permanently sequestered over the lifespan of the project in the Weyburn and Midale fields. The gas is being supplied via a 320 kilometre mile long pipeline (completed in 1999) from the lignite-fired Dakota Gasification Company synfuels plant site in Beulah, North Dakota (See attached image). The company is a subsidiary of Basin Electric Power Co-operative. At the plant, CO is produced from a Rectisol unit in the gas cleanup train. The CO project adds about $30 million of gross revenue to the gasification plant's cash flow each year. Approximately 8000 tonnes/day of compressed CO (in liquid form) is provided to the Weyburn and Midale fields via the pipeline. During its life, the Weyburn and Midale fields combined are expected to produce at least 220 million additional barrels of incremental oil, through miscible or near-miscible displacement with CO, from a fields that have already produced over since discovery in 1954. This will extend the life of the Weyburn field by approximately 20–25 years. It is estimated that ultimate oil recovery will increase to 34% of the oil-in-place. It has been estimated that, on a full life-cycle basis, the oil produced at Weyburn by CO EOR will release only two-thirds as much CO to the atmosphere compared to oil produced using conventional technology | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project This is the first instance of cross-border transfer of CO from the US to Canada and highlights the ability for international cooperation with GHG mitigation technologies. Whilst there are emissions trading projects being developed within countries such as Canada, the Weyburn project is essentially the first international project where physical quantities of CO are being sold commercially for enhanced oil recovery, with the added benefit of carbon sequestration. The First Phase of the IEAGHG Weyburn CO Monitoring and Storage Project (the Midale oil field did not join the research project until the Final phase research) which began in 2000 and ended in 2004, verified the ability of an oil reservoir to securely store CO for significant lengths of time. This was done through a comprehensive analysis of the various process factors as well as monitoring/modeling methods designed to measure, monitor and track the CO. Research was conducted into geological characterization of both the geosphere (the geological layers deeper than near surface) and biosphere (basically from the depths of groundwater up). As well, prediction, monitoring and verification techniques were used to examine the movements of the CO. Finally, both the economic and geologic limits of the CO storage capacity were predicted, and a long-term risk assessment developed for storage of CO permanently in the formation. A critical part of the First Phase was the accumulation of baseline surveys for both CO soil content, and water wells in the area | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project These baselines were identified in 2001 and have helped to confirm through comparison with more recent readings that CO is not leaking from the reservoir into the biosphere in the study area. • Based on preliminary results, the natural geological setting of the oil field was deemed to be highly suitable for long-term CO geological storage • The results form the most complete, comprehensive, peer-reviewed data set in the world for CO geological storage. However, additional research was deemed to be needed to further develop and refine CO monitoring and verification technologies. With this in mind, a second and final phase of research was developed and began in the year 2005, and will be completed in 2011. The PTRC and IEA GHG issued a full report on the first phase, and it is available from the PTRC's website. The Final Phase of the IEAGHG Weyburn-Midale CO Monitoring and Storage Project is utilizing scientific experts from most of the world's leading carbon capture and storage research organizations and universities to further develop and build upon the most scrutinized CO geological storage data set in the world. The project's major technical research "themes" can be broadly broken out into four areas: Technical Components: Ultimately, the goal of the final phase of the project is to produce a best practices manual that can be used by other jurisdictions and organizations to help transition CO-EOR operations into long-term storage projects | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project The research of the project's final phase should be complete in 2011, with the Best Practices Manual issued before the end of that year. A report of leaks above the project was released in January 2011 by an advocacy group on behalf of owners of land above the project. They reported ponds fizzing with bubbles, dead animals found near those ponds, sounds of explosions which they attributed to gas blowing out holes in the walls of a quarry. The report said that carbon dioxide levels in the soil averaged about 23,000 parts per million, several times higher than is normal for the area. "The ... source of the high concentrations of CO2 in the soils of the Kerr property is clearly the anthropogenic CO2 injected into the Weyburn reservoir... The survey also demonstrates that the overlying thick cap rock of anhydrite over the Weyburn reservoir is not an impermeable barrier to the upward movement of light hydrocarbons and CO2 as is generally thought." said the report. The PTRC posted an extensive rebuttal of the Petro-Find report, stating that the isotopic signatures of the , claimed by Mr. Lafleur to be indicative of the manmade being injected into the reservoir, were in fact, according to studies of conducted by the British Geological Survey and two other European Union geological groups prior to being injected at Weyburn, occurring naturally in several locations near the Kerr farm. Subsequent soil surveys after injection in 2002 to 2005 found levels dropped in these same regions | https://en.wikipedia.org/wiki?curid=30426861 |
Weyburn-Midale Carbon Dioxide Project In addition, prior to injection occurring into the oil field, these samplings were found to be as high as 125,000 parts per million and averaging 25,000 ppm across the region, even more than the average and largest readings from the Kerr's property that were being claimed as unusually high. The report also questions, based on seismic imaging conducted over ten years, that any active faults exist or that the caprock is compromised to allow pathways for the to reach the surface. The PTRC acknowledged that they do not monitor the entire site for leaks, rather primarily above the part of the Weyburn field where is injected and key locations outside it, but the organization did monitor the Kerr's well between 2002 and 2006, finding no appreciable difference in water quality. They have also acknowledged that PTRC is a research organisation rather than a regulator, and manage the IEA GHG Weyburn-Midale Monitoring and Storage Project on behalf of the International Energy Agency's Greenhouse Gas R&D Programme, which includes some 30 international research groups. | https://en.wikipedia.org/wiki?curid=30426861 |
Proximity ligation assay (in situ PLA) is a technology that extends the capabilities of traditional immunoassays to include direct detection of proteins, protein interactions and post translational modifications with high specificity and sensitivity. Protein targets can be readily detected and localized with single molecule resolution and objectively quantified in unmodified cells and tissues. Utilizing only a few cells, sub-cellular events, even transient or weak interactions, are revealed in situ and sub-populations of cells can be differentiated. Within hours, results from conventional co-immunoprecipitation and co-localization techniques can be confirmed. Two primary antibodies raised in different species recognize the target antigen on the proteins of interest (Figure 1). Secondary antibodies (2 Ab) directed against the constant regions of the different primary antibodies, called PLA probes, bind to the primary antibodies (Figure 2). Each of the PLA probes has a short sequence specific DNA strand attached to it. If the PLA probes are in proximity (that is, if the two original proteins of interest are in proximity, or part of a protein complex, as shown in the figures), the DNA strands can participate in rolling circle DNA synthesis upon addition of two other sequence specific DNA oligonucleotides together with appropriate substrates and enzymes (Figure 3). The DNA synthesis reaction results in several-hundredfold amplification of the DNA circle | https://en.wikipedia.org/wiki?curid=30439786 |
Proximity ligation assay Next, fluorescent-labeled complementary oligonucleotide probes are added, and they bind to the amplified DNA (Figure 4). The resulting high concentration of fluorescence is easily visible as a distinct bright spot when viewed with a fluorescence microscope. In the specific case shown (Figure 5), the nucleus is enlarged because this is a B-cell lymphoma cell. The two proteins of interest are a B cell receptor and MYD88. The finding of interaction in the cytoplasm was interesting because B cell receptors are thought of as being located in the cell membrane. PLA as described above has been used to study aspects of animal development and breast cancer among many other topics. A variation of the technique (rISH-PLA) has been used to study the association of protein and RNA. Another variation of in situ PLA includes a multiplex PLA assay that makes it possible to visualize multiple protein complexes in parallel. PLA can also be combined with other read out forms such as ELISA, flow cytometry. and Western blotting | https://en.wikipedia.org/wiki?curid=30439786 |
List of brazing alloys List of brazing alloys | https://en.wikipedia.org/wiki?curid=30444895 |
Yuhwang-ori Yuhwang ori(유황오리) is a traditional Korean dish, made of duck raised with special sulfur. Yuhwang(유황) and Ori(오리) are Korean word. Yuhwang is a mineral medicine, made by melting natural sulfur after removing unuseful things. Yuhwang is used to cure diseases like diarrhea or hemorrhoid that are caused by cold stomach. Ori means duck in English. Because Yuhwang is element that has strong toxicity, most of birds die after breathing Yuhwang gas even a little. It is hard to find animal that can live after eating Yuhwang, except duck. Especially, duck have strong detoxification ability. By feeding Yuhwang to duck, Yuhwang's toxicity disappears remaining its good components. Duck has great resistance in disease and ability of adapt. So it was used in invigoratant to human since long times ago, because of its good nature of a medicine. Yuhwang ori has been eaten in folk remedies since very long times ago. Yuhwang can keep the body warm, and make bones stronger. However, Yuhwang is hard to be used in medicine, because of its toxicity. To people, eating Yuhwang ori can prevent stroke, high blood-pressure, anemia and so on. Yuhwang ori can lower cholesterol rate in our body and can be a great medicine for stroke and circulatory system disease. If we feed Yuhwang that have warm temper to duck which have cold-water temper, the synergism effect occurs by neutralisation of Yuhwang and duck's detoxification. And highest detoxification and medicine effect come up | https://en.wikipedia.org/wiki?curid=30452167 |
Yuhwang-ori That's why Yuhwang ori has prevention and cure on cancer, infection, backache, neuralgia, arthritis, rheumatism, high blood-pressure, hardening of arteries, stroke, blood circulation and so on. Yuhwang ori has 6 times more protein than rice and 3.35 times more vitamin than chicken. Because Yuhwang ori contains plenty of vitamin C and vitamin B, it can improve stamina, prevent decline of concentration and drive out chronic fatigue. In addition, recent scientists found that duck meat have alkalinity and its oil has linoleic acid(essential fatty acid for human), which means that Yuhwang ori makes blood flow smoothly and lower cholesterol rate in the body | https://en.wikipedia.org/wiki?curid=30452167 |
Process miniaturization Chemical process miniaturization refers to a philosophical concept within the discipline of process design that challenges the notion of "economy of scale" or "bigger is better". In this context, process design refers to the discipline taught primarily to chemical engineers. However, the emerging discipline of process miniaturization will involve integrated knowledge from many areas; as examples, systems engineering and design, remote measurement and control using intelligent sensors, biological process systems engineering, and advanced manufacturing robotics, etc. One of the challenges of chemical engineering has been to design processes based on chemical laboratory-scale methods, and to scale-up processes so that products can be manufactured that are economically affordable. As a process becomes larger, more product can be produced per unit time, so when a process technology becomes established or mature, and operates consistently without upsets or “downtime”, more economic efficiency can be gained from scale-up. Given a fixed price for the feedstock (e.g. the price per barrel of crude oil), the product cost can be decreased using a larger scale process because the capital investment and operational costs do not normally increase linearly with scale. For example, the capacity or volume of a cylindrical vessel used to produce a product increases proportional to the square of the radius of the cylinder, so cost of materials per unit volume decreases | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization But the costs to design and fabricate the vessel have traditionally been less sensitive to scale. In other words, one can design a small vessel and fabricate it for about the same cost as the larger vessel. In addition, the cost to control and operate a process (or a process unit component) does not change substantially with the scale. For example, if it takes one operator to operate a small process, that same operator can probably operate the larger process. The economy of scale concept, as taught to chemical engineers, has led to the notion that one of the objectives of process development and design is to achieve “economy of scale” by scaling-up to the largest possible size processing plant so that the product cost can be economically affordable. This disciplinary philosophy has been reinforced by example designs in the petroleum refining and petrochemical industries, where feedstocks have been transported as fluids in pipelines, large tanker ships, and railcars. Fluids, by definition are materials that flow and can be transferred using pumps or gravity. Therefore, large pumps, valves, and pipelines exist to transfer large amounts of fluids in the process industries. Process miniaturization, in contrast, will involve processing of large amounts of solids from renewable biomass resources; therefore, new thinking towards process designs optimized for solids processing will be required. The concept of a microprocess has been defined by S. S. Sofer while a professor at the New Jersey Institute of Technology | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization A microprocess has the following characteristics: The microprocess design philosophy has been largely envisioned by historical analysis of the role that component miniaturization has played in the information technology industry. It is the evolution of the miniaturization of computer hardware that has enabled the thinking about process miniaturization, in the chemical engineering design context. Rather than the traditional design objective as “scale-up” of processing to one centralized large processing plant (e.g. the mainframe), one can envision achieving the economic objectives using a “scale-out” philosophy (e.g. multiple microcomputers). Electrical and electronic devices have always played an important role in chemical process plant automation. However, initially, simple thermometers such as those containing mercury, and pressure gauges which were completely mechanical in nature were used to monitor process conditions (such as the temperature, pressure and level in a chemical reactor). Process conditions were adjusted based largely on a human operator's heuristic knowledge of the process behavior. Even with electronic automation installed, many process still require substantial operator interaction, particularly during the start-up phase of the process, or during deployment of a new technology | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization Process control of the future will involve the widespread utilization of intelligent sensors, and mass-produced intelligent miniaturized devices such as programmable logic controllers that communicate wirelessly to process actuators. Since these devices will be miniaturized to reduce manufacturing cost, this enables the devices to be embedded in structures so that they become invisible to the casual observer. The cost of such sensors will likely be reduced to a point where they either "function or don't function". When that cost threshold has been reached, the repair procedure will be to disable the sensor, and to actuate a redundant working sensor. In otherwords, entire complex control systems will become so low cost, that repair will not be economically viable. The intelligence of the process will be developed using process simulation models based on scientific fundamentals. Heuristic rules will be programmed into the micro-controllers, which will largely eliminate the need for constant monitoring by human heuristic knowledge of the process behavior. Process which can automatically self-optimize through advanced algorithms developed by microprocess engineers will be embedded, and only accessible to the knowledge-owner. This will enable the construction of large networks of automous microprocesses. Advanced process control systems for process miniaturization will increase the need for controlling the security and ownership of process intelligence in a knowledge-based business | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization It will become more difficult to control intellectual property through the traditional method of patents; therefore, trademarks, brand recognition, and copyright laws will play a more important role in value security for knowledge-based businesses of the future. Techno-economic analysis, as taught in traditional chemical process design, will also dramatically shift from a conservative viewpoint of utilization of historical trend economics and cash flow analysis. Economic viability of a given enterprise will be more linked to acquisition of real-time economic information, that can rapidly change based on empirical observations created by an emerging discipline of microprocess development systems; therefore, the models will be more based on "what can be?" rather that "what has the past shown?" Rather than one large central plant, that has to be fed a large amount of feedstock, such as a refinery that can unload a tanker shipment of petroleum if located next to an ocean, the discipline of process miniaturization envisions the distribution of the process technology to areas where the feedstock is not readily transportable in large quantities to a large centralized processing plant. The miniaturized process technology may simply involve transformation of solid biomass materials from multiple distributed microprocesses into more easily manageable fluids. The fluids can then be transported or distributed to larger-scale intelligent processing nodes using conventional fluid transport technology | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization Historically, small processes or microprocesses "per se" have always existed. For example, small vineyards and breweries have produced feedstock, processed it, and stored product in what could be considered “microprocess” when compared to processes designed based on the petrochemical industry model or, for example, large-scale production of beer. Small villages in India and other places in the world have learned to produce biogas from animal manure in what could be considered small-scale microprocesses for the production of energy. However, microprocesses and process miniaturization as a design philosophy includes the notion of approaching total automation, and is a new technology which has been enabled by computer hardware miniaturization, for example, the microprocessor. It is easy to envision processes which can be mass-produced and transported. For example, many appliances such as air conditioners, domestic washing machines, and refrigerators could be considered microprocesses. The design philosophy of process miniaturization envisions that “scale-down” of complex processes involving multiple process unit operations can be achieved, and that economy of scale will be more related to the size of a network of distributed autonomous microprocesses. Since failure of one autonomous microprocess does not cause shutdown of the entire network, microprocesses will lead to more economically efficient, robust, and stable production of products that have traditionally been produced for a petroleum-based society | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization Since fossil fuels by definition are being consumed and are non-renewable, future fuel and materials will be based on renewable biomass. The conversion of biomass into energy is perhaps more challenging to the technologist than energy from fossil fuels. Water, dissolved organic and inorganic compounds, and solid particulates of various size can be present in biomass processes. It is perhaps the development of microbial fuel cells where the philosophical thinking of process miniaturization will play a wider role. Distribution of knowledge, in a fashionable, intriguing style through miniaturized devices, can be substantially enhanced (accelerated) by low power consuming devices (such as smart phones). A rethinking of "what is a powerplant?" can create enormous innovations, given recent advances in membrane materials of construction, immobilized whole cell methodologies, metabolic engineering, and nanotechnology. The challenges of microbial fuel cells relate mainly to finding lower cost manufacturing methods, materials of construction, and systems design. Bruce Logan from the Penn State University has described in several research articles and reviews these challenges. However, even with existing designs which generate low power, there are applications in distribution of electrical recharging systems to remote areas of Africa, where smart phone, can enable access to the vast information of the internet, and to provide lighting | https://en.wikipedia.org/wiki?curid=30458081 |
Process miniaturization These systems can run on agricultural, animal and human waste streams using naturally occurring bacteria. Nuclear power is considered "green technology" in that it does not produce carbon dioxide, a green house gas, as do traditional natural gas or coal-fired power plants. The economics of the deployment of mini nuclear reactors has been discussed in an article in "The Economist". The advantages of mini nuclear reactors has also been discussed by Secretary of Energy, Steven Chu. As discussed by Chu, the reactors would be manufactured in a factory-like situation and then transported, intact by rail or ship to different parts of the country or world. Economy of scale by size is replaced by economy of scale by number. Many companies are not willing to accept the risk of investing $8B to $9B dollars in single large reactor, so one of the most attractive features of process miniaturization is a reduction in the risk of capital investment, and the possibility of recovering investment by reselling and relocating a functional turn-key microprocess to a new owner - a major economic advantage of the portability of microprocesses. | https://en.wikipedia.org/wiki?curid=30458081 |
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