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radiation element design, and overall efficiency, as well as the associated theoretical limits are presently a subject of research, as it was demonstrated by the Special Session on "Analysis of Electromagnetic Wireless Systems for Solar Power Transmission" held during the 2010 IEEE Symposium on Antennas and Propagation... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
km into space, but because of their small generation capacity, hundreds or thousands of laser satellites would need to be launched in order to create a sustainable impact. A single satellite launch can range from fifty to four hundred million dollars. Lasers could be helpful for the energy from the sun harvested in spa... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
connected via diodes. Microwave broadcasts from the satellite would be received in the dipoles with about 85% efficiency. With a conventional microwave antenna, the reception efficiency is better, but its cost and complexity are also considerably greater. Rectennas would likely be several kilometers across. === In spac... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
the art for flown spacecraft, which as of 2015 was 150 W/kg (6.7 kg/kW), and improving rapidly. Very lightweight designs could likely achieve 1 kg/kW, meaning 4,000 metric tons for the solar panels for the same 4 GW capacity station. Beyond the mass of the panels, overhead (including boosting to the desired orbit and s... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
relied less on human presence in space and more on partially self-replicating systems on the lunar surface under remote control of workers stationed on Earth. The high net energy gain of this proposal derives from the Moon's much shallower gravitational well. Having a relatively cheap per pound source of raw materials ... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
return a 500,000-ton asteroid fragment to geostationary orbit. Only about 3,000 tons of the mining ship would be traditional aerospace-grade payload. The rest would be reaction mass for the mass-driver engine, which could be arranged to be the spent rocket stages used to launch the payload. Assuming that 100% of the re... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
military potential of such a system is readily apparent. With good array sidelobe design, outside the receiver may be less than the OSHA long-term levels as over 95% of the beam energy will fall on the rectenna. However, any accidental or intentional mis-pointing of the satellite could be deadly to life on Earth within... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
Such a system would not focus its power beam very effectively anywhere that did not have a pilot beam transmitter. The long-term effects of beaming power through the ionosphere in the form of microwaves has yet to be studied. == Timeline == === In the 20th century === 1941: Isaac Asimov published the science fiction sh... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
requires numerous significant advances in current technology and capabilities. A technology roadmap has been developed that lays out potential paths for achieving all needed advances — albeit over several decades. === In the 21st century === 2001: NASDA (One of Japan's national space agencies before it became part of J... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
China towards developing a solar power satellite, during a visit by former Indian President Dr APJ Abdul Kalam. 2015: The Space Solar Power Initiative (SSPI) is established between Caltech and Northrop Grumman Corporation. An estimated $17.5 million is to be provided over a three-year project for development of a space... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
reentry would destroy too much ozone. 2016: Ian Cash of SICA Design proposes CASSIOPeiA (Constant Aperture, Solid State, Integrated, Orbital Phased Array) a new concept SPS Faculty Listing | Electrical and Computer Engineering 2017: NASA selects five new research proposals focused on investments in space. The Colorado ... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
for the individual satellite is in the 1-10 GW range and usually involves planar or concentrated solar photovoltaics (PV) as the energy collector / conversion. The most typical transmission designs are in the 1–10 GHz (2.45 or 5.8 GHz) RF band where there are minimum losses in the atmosphere. Materials for the satellit... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
MEO: MEO systems have been proposed for in-space utilities and beam-power propulsion infrastructures. For example, see Royce Jones' paper. Highly elliptical orbits: Molniya, Tundra, or Quazi Zenith orbits have been proposed as early locations for niche markets, requiring less energy to access and providing good persist... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
thin wall platic tube filled with low pressure (2.4 kPa) and temperature (20 deg C) steam. Solar pumped laser: Japan has pursued a solar-pumped laser, where sunlight directly excites the lasing medium used to create the coherent beam to Earth. Stellaser: A hypothetical concept of a very large laser where a star provide... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
floating components: Solaren has proposed an alternative to the monolithic structure where the primary reflector and transmission reflector are free-flying. Spin stabilization: NASA explored a spin-stabilized thin film concept. Photonic laser thruster (PLT) stabilized structure: Young Bae has proposed that photon press... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
designs make use of the developed industrial manufacturing system extant on Earth, and use Earth based materials both for the satellite and propellant. Variants include: Lunar materials: Designs exist for Solar Power Satellites that source >99% of materials from lunar regolith with very small inputs of "vitamins" from ... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
system is very high mass-flow at low total cost. Alternate concepts include: Lunar chemical launch: ULA has recently showcased a concept for a fully re-usable chemical lander XEUS to move materials from the Lunar surface to LLO or GEO. Lunar mass driver: Launch of materials from the lunar surface using a system similar... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
irradiation of a mono-propellant launch vehicle using RF energy. The RF energy is absorbed and directly heats the propellant not unlike in NERVA-style nuclear-thermal. LaserMotive has a concept for a laser-based approach. == Gallery == == See also == Attitude dynamics and control – Process of controlling orientation of... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
array by 2040. Space Energy, Inc. - Space Energy, Inc. Whatever happened to solar power satellites? An article that covers the hurdles in the way of deploying a solar power satellite. Solar Power Satellite from Lunar and Asteroidal Materials Archived 2020-09-25 at the Wayback Machine Provides an overview of the technol... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
Powering the Planet 20-minute streaming video from The Futures Channel that provides a "101" on space-based solar power Space Solar Power NewSpace 2010 Panel, 72 minutes Space Solar Power and Space Energy Systems SSI – Space Manufacturing 14 Panel – 2010 – 27 min NASA DVD in 16 Parts Exploring New Frontiers for Tomorro... | {
"page_id": 6757017,
"title": "Space-based solar power"
} |
An endoskeleton (From Ancient Greek ἔνδον, éndon = "within", "inner" + σκελετός, skeletos = "skeleton") is a structural frame (skeleton) — usually composed of mineralized tissue — on the inside of an animal, overlaid by soft tissues. Endoskeletons serve as structural support against gravity and mechanical loads, and pr... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
function purely for structural support (as in the case of Porifera), but often also serves as an attachment site for muscles and a mechanism for transmitting muscular forces as in chordates and echinoderms, which provides a means of locomotion. Compared to the exoskeleton structure in many invertebrates (particularly p... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
tissues, while exoskeletons are directly exposed to external insults. Having other tissues attached outside the skeleton means that endoskeletons can have a more diverse muscular layouts as well as bigger physiological cross-sectional area, which translates to greater contractile strength and adaptability. Having exter... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
endoskeleton is greatly expanded. During embryonic development, the notochord becomes segmentally replaced by a much tougher vertebral column (i.e. the spine) composed of stiffer structural elements called vertebrae. Notochord remnants are transformed into intervertebral discs, which give some range of motion between t... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
result, vertebrates have gradually dominated all high-level niches in both aquatic and terrestrial ecosystems since the Devonian (circa. 420-359 Mya). === Echinoderms === Echinoderms have a mesodermal skeleton in the dermis, composed of calcite-based plates known as ossicles, which form a porous structure known as ster... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
survival strategy, by having tiny grappling hook-like spicules (microscleres) that extends outwards like burs to snag and trap passing-by aquatic animals such as small fish and crustaceans. As sponges don't have dedicated digestive systems, these predatory sponges rely on symbiotic organisms such as scale worms and mic... | {
"page_id": 662173,
"title": "Endoskeleton"
} |
The molecular formula C3H8S2 (molar mass: 108.23 g/mol) may refer to: 2,4-Dithiapentane Propanedithiols 1,2-Propanedithiol 1,3-Propanedithiol | {
"page_id": 12196510,
"title": "C3H8S2"
} |
The molecular formula C5H8O4 may refer to: Acetolactic acid 4,5-Dihydroxy-2,3-pentanedione Dimethyl malonate Glutaric acid 4-Hydroxy-2-oxopentanoic acid 2-Methylsuccinic acid Xylosan | {
"page_id": 12262046,
"title": "C5H8O4"
} |
Victor H. Yngve (July 5, 1920 – January 15, 2012) was a professor of linguistics at the University of Chicago and the Massachusetts Institute of Technology (1953-1965). He was one of the earliest researchers in computational linguistics and natural language processing, the use of computers to analyze and process langua... | {
"page_id": 3283616,
"title": "Victor Yngve"
} |
8, 2024. == External links == Interview Archived May 14, 2007, at the Wayback Machine, dcs.shef.ac.uk; accessed August 15, 2017. Interview video; accessed August 15, 2017. In Memoriam | {
"page_id": 3283616,
"title": "Victor Yngve"
} |
Time-resolved fluorescence energy transfer (TR-FRET) is the practical combination of time-resolved fluorometry (TRF) with Förster resonance energy transfer (FRET) that offers a powerful tool for drug discovery researchers. TR-FRET combines the low background aspect of TRF with the homogeneous assay format of FRET. The ... | {
"page_id": 38345378,
"title": "Time-resolved fluorescence energy transfer"
} |
to scattered light (e.g. precipitated compounds) is normally polarized. Depending on the assay configuration, either case can lead to a false positive or false negative result. However, because the donor species used in a TR-FRET assay has a fluorescent lifetime that is many orders of magnitude longer than background f... | {
"page_id": 38345378,
"title": "Time-resolved fluorescence energy transfer"
} |
steady-state fluorescence measurement presents serious limitations in assay sensitivity. Long-lived fluorophores, such as lanthanides, combined with time-resolved detection (a delay between excitation and emission detection) minimizes prompt fluorescence interference. This method (commonly referred to as time-resolved ... | {
"page_id": 38345378,
"title": "Time-resolved fluorescence energy transfer"
} |
to measure the assay then delays the reading of the emitted light by several hundred milliseconds after the incident/excitation light (the light energy pulse supplied by the instrument to excite the donor molecule) in order to eliminate any 'cross-talk' between the excitation and emission signals. ('cross-talk' in this... | {
"page_id": 38345378,
"title": "Time-resolved fluorescence energy transfer"
} |
The Chandrasekhar limit () is the maximum mass of a stable white dwarf star. The currently accepted value of the Chandrasekhar limit is about 1.4 M☉ (2.765×1030 kg). The limit was named after Subrahmanyan Chandrasekhar. White dwarfs resist gravitational collapse primarily through electron degeneracy pressure, compared ... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
In the nonrelativistic case, electron degeneracy pressure gives rise to an equation of state of the form P = K1ρ5/3, where P is the pressure, ρ is the mass density, and K1 is a constant. Solving the hydrostatic equation leads to a model white dwarf that is a polytrope of index 3/2 – and therefore has radius inversely... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
( μ e m H ) 2 {\displaystyle M_{\text{limit}}={\frac {\omega _{3}^{0}{\sqrt {3\pi }}}{2}}\left({\frac {\hbar c}{G}}\right)^{\frac {3}{2}}{\frac {1}{(\mu _{\text{e}}m_{\text{H}})^{2}}}} where: ħ is the reduced Planck constant c is the speed of light G is the gravitational constant μe is the average molecular weight per ... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
kg (for μe = 2.5). Stoner went on to derive the pressure–density equation of state, which he published in 1932. These equations of state were also previously published by the Soviet physicist Yakov Frenkel in 1928, together with some other remarks on the physics of degenerate matter. Frenkel's work, however, was ignore... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
in 1932 by the Soviet physicist Lev Landau, who, however, did not apply it to white dwarfs and concluded that quantum laws might be invalid for stars heavier than 1.5 solar mass. === Chandrasekhar–Eddington dispute === Chandrasekhar's work on the limit aroused controversy, owing to the opposition of the British astroph... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
that stars might collapse to nothing. As a result, Chandra's work was almost forgotten.: 150 However, Chandrasekhar chose to move on, leaving the study of stellar structure to focus on stellar dynamics.: 51 In 1983 in recognition for his work, Chandrasekhar shared a Nobel prize "for his theoretical studies of the physi... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
is carried away by the emitted neutrinos and the kinetic energy of the expanding shell of gas; only about 1% is emitted as optical light. This process is believed responsible for supernovae of types Ib, Ic, and II. Type Ia supernovae derive their energy from runaway fusion of the nuclei in the interior of a white dwarf... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
dwarfs, so that the limit was only violated momentarily. Another way to potentially explain the problem of the Champagne Supernova was considering it the result of an aspherical explosion of a white dwarf. However, spectropolarimetric observations of SN 2009dc showed it had a polarization smaller than 0.3, making the l... | {
"page_id": 6813,
"title": "Chandrasekhar limit"
} |
An ecozone may refer to: Biogeographic realm, the broadest biogeographic division of Earth's land surface (referred to as ecozone by BBC) Biome, a large collection of flora and fauna occupying a major habitat Bioregion, an ecologically and geographically defined area that is smaller than a biogeographical realm, but la... | {
"page_id": 51976868,
"title": "Ecozone"
} |
The Fine-Resolution Epithermal Neutron Detector (FREND) is a neutron detector that is part of the instrument payload on board the Trace Gas Orbiter (TGO), launched to Mars in March 2016. This instrument is currently mapping hydrogen levels to a maximum depth of 1 m (3 ft 3 in) beneath the Martian surface, thus revealin... | {
"page_id": 58006182,
"title": "Fine-Resolution Epithermal Neutron Detector"
} |
releasing high-energy neutrons, which can be measured by FREND instrument. The distribution of neutron velocities measured reveals the hydrogen content, which are a good indicator of hydrogen abundance —water or hydrated minerals— in the shallow subsurface of Mars. FREND uses inherited technology developed by the Russi... | {
"page_id": 58006182,
"title": "Fine-Resolution Epithermal Neutron Detector"
} |
The molecular formula C5H9NO2 (molar mass : 115.13 g/mol) may refer to: Allylglycine (+)-cis-2-Aminomethylcyclopropane carboxylic acid Dimethylaziridine carboxylic acid N-Formylmorpholine Proline, an amino acid | {
"page_id": 12262054,
"title": "C5H9NO2"
} |
In mathematical physics, the Peres metric is defined by the proper time d τ 2 = d t 2 − 2 f ( t + z , x , y ) ( d t + d z ) 2 − d x 2 − d y 2 − d z 2 {\displaystyle {d\tau }^{2}=dt^{2}-2f(t+z,x,y)(dt+dz)^{2}-dx^{2}-dy^{2}-dz^{2}} for any arbitrary function f. If f is a harmonic function with respect to x and y, then th... | {
"page_id": 25369256,
"title": "Peres metric"
} |
The molecular formula C5H9NO may refer to: 3-Dimethylaminoacrolein 2-Ethyl-2-oxazoline N-Methyl-2-pyrrolidone N-Methyl-4-pyrrolidone 4-Piperidinone 2-Piperidinone | {
"page_id": 12262057,
"title": "C5H9NO"
} |
In atomic physics, even–even (EE) nuclei are nuclei with an even number of neutrons and an even number of protons. Even-mass-number nuclei, which comprise 151/251 = ~60% of all stable nuclei, are bosons, i.e. they have integer spin. The vast majority of them, 146 out of 151, belong to the EE class; they have spin 0 bec... | {
"page_id": 66001579,
"title": "Even–even nucleus"
} |
Smash and Grab is the name given to a technique developed by Charles S. Hoffman and Fred Winston used in molecular biology to rescue plasmids from yeast transformants into Escherichia coli, also known as E. coli, in order to amplify and purify them. In addition, it can be used to prepare yeast genomic DNA (and DNA from... | {
"page_id": 53942957,
"title": "Smash and Grab (biology)"
} |
2-Methylisoborneol (MIB) is an irregular monoterpene derived from the universal monoterpene precursor geranyl pyrophosphate. MIB and the irregular sesquiterpene geosmin together account for the majority of biologically-caused taste and odor outbreaks in drinking water worldwide. MIB has a distinct earthy or musty odor,... | {
"page_id": 21764781,
"title": "2-Methylisoborneol"
} |
Acclimatization or acclimatisation (also called acclimation or acclimatation) is the process in which an individual organism adjusts to a change in its environment (such as a change in altitude, temperature, humidity, photoperiod, or pH), allowing it to maintain fitness across a range of environmental conditions. Accli... | {
"page_id": 400047,
"title": "Acclimatization"
} |
high or low temperatures display relatively high resting levels of heat shock proteins so that when they are exposed to even more extreme temperatures the proteins are readily available. Expression of heat shock proteins and regulation of membrane fluidity are just two of many biochemical methods organisms use to accli... | {
"page_id": 400047,
"title": "Acclimatization"
} |
data. The degree to which organisms are able to acclimate is dictated by their phenotypic plasticity or the ability of an organism to change certain traits. Recent research in the study of acclimation capacity has focused more heavily on the evolution of phenotypic plasticity rather than acclimation responses. Scientis... | {
"page_id": 400047,
"title": "Acclimatization"
} |
altitude continues for months or even years after initial ascent, and ultimately enables humans to survive in an environment that, without acclimatization, would kill them. Humans who migrate permanently to a higher altitude naturally acclimatize to their new environment by developing an increase in the number of red b... | {
"page_id": 400047,
"title": "Acclimatization"
} |
The Global Food Safety Initiative (GFSI) is a private organization that works as a "coalition of action" from the Consumer Goods Forum (CGF) and brings together retailers and brand owners (manufacturers) from across the CGF membership. The GFSI operates under multi-stakeholder governance, with the objective to create "... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
supply chain. Other important activities include the development of a capacity-building program for small and/or less developed businesses to facilitate their access to local markets, and a continuous focus on food safety auditor competence to bring industry experts in collaboration with key stakeholders to a common co... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
a safer supply chain. GFSI was created to achieve this through the harmonization of food safety standards that would help mitigate liability exposure for retailers and reduce audit duplication throughout the supply chain. At the time, there was no existing scheme that could be adopted by all. GFSI therefore chose to im... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
These are regularly revised by GFSI to reflect improvements in best practices. GFSI is not a CPO in itself and does not carry out any accreditation or certification activities. The status of recognition is achieved through a comprehensive benchmarking process. Once a standard has gained formal recognition by the GFSI s... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
products, processes, and services Certification programmes following ISO/IEC 17021 must also meet the requirements of ISO 22003-1 certification of food safety management systems; ISO 22003-2 certification of food safety systems is supplemental to ISO/IEC 17065. ISO 17021 and ISO 17065 follow ISO/IEC 17000 for vocabular... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
legal obligation stimulated a parallel development of private standards as self-regulation tools, adding to the global food sector's burden, as the requirements were focused on liability mitigation against EU food law. Retailers were cautious to avoid potential scandals, which resulted in taking the lead on technical c... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
international standard was adopted. Retailers rejected the proposal due to their close relationships with scheme owners using private standards. The proposal was raised again in 2020, and GFSI restated their position not to have one standard for the food industry. Promoting ISO 22000 for food and farming would mean red... | {
"page_id": 27531955,
"title": "Global Food Safety Initiative"
} |
Reaction kinetics in uniform supersonic flow (French: Cinétique de Réaction en Ecoulement Supersonique Uniforme, CRESU) is an experiment investigating chemical reactions taking place at very low temperatures. The technique involves the expansion of a gas or mixture of gases through a de Laval nozzle from a high-pressur... | {
"page_id": 6839,
"title": "Reaction kinetics in uniform supersonic flow"
} |
varied up to the maximum corresponding to the flow time over that known distance. By studying how quickly the reagent species disappears in the presence of differing concentrations of a (usually stable) co-reagent species, the reaction rate constant at the low temperature of the CRESU flow can be determined. Reactions ... | {
"page_id": 6839,
"title": "Reaction kinetics in uniform supersonic flow"
} |
In genetic algorithms and genetic programming defining length L(H) is the maximum distance between two defining symbols (that is symbols that have a fixed value as opposed to symbols that can take any value, commonly denoted as # or *) in schema H. In tree GP schemata, L(H) is the number of links in the minimum tree fr... | {
"page_id": 1514171,
"title": "Defining length"
} |
August William Kuchler (born August Wilhelm Küchler; 26 July 1907 – 17 June 1999) was a German-born American geographer and naturalist who is noted for developing a plant association system that has become widely used in the United States. Some of this database has been digitized for integration into GIS mapping system... | {
"page_id": 19995323,
"title": "A. W. Kuchler"
} |
The molecular formula C5H9NO3 (molar mass : 131.13 g/mol) may refer to: Aminolevulinic acid, first compound in the porphyrin synthesis pathway Glutamate-1-semialdehyde Glutamate-5-semialdehyde Hydroxyproline | {
"page_id": 12262075,
"title": "C5H9NO3"
} |
The molecular formula C5H9NO3S (molar mass: 163.195 g/mol, exact mass: 163.0303 u) may refer to: Acetylcysteine, also known as N-acetylcysteine (NAC) Tiopronin | {
"page_id": 12262079,
"title": "C5H9NO3S"
} |
Dinitrophenols are chemical compounds which are nitro derivatives of phenol. There are six isomers of dinitrophenol: 2,3-Dinitrophenol 2,4-Dinitrophenol 2,5-Dinitrophenol 2,6-Dinitrophenol 3,4-Dinitrophenol 3,5-Dinitrophenol Dinitrophenols also form the core structure of some herbicides, which are collectively referred... | {
"page_id": 3218113,
"title": "Dinitrophenol"
} |
Hydrophilic interaction chromatography (or hydrophilic interaction liquid chromatography, HILIC) is a variant of normal phase liquid chromatography that partly overlaps with other chromatographic applications such as ion chromatography and reversed phase liquid chromatography. HILIC uses hydrophilic stationary phases w... | {
"page_id": 7150276,
"title": "Hydrophilic interaction chromatography"
} |
well as weak electrostatic mechanisms under the high organic solvent conditions used for retention. This distinguishes HILIC as a mechanism distinct from ion exchange chromatography. The more polar compounds will have a stronger interaction with the stationary aqueous layer than the less polar compounds. Thus, a separa... | {
"page_id": 7150276,
"title": "Hydrophilic interaction chromatography"
} |
to enhance elimination from the cellular tissue. This separation technique is also particularly suitable for glycosylation analysis and quality assurance of glycoproteins and glycoforms in biologic medical products. For the detection of polar compounds with the use of electrospray-ionization mass spectrometry as a chro... | {
"page_id": 7150276,
"title": "Hydrophilic interaction chromatography"
} |
e-HILIC, reflecting retention mechanisms sensitive to a particular ionic portion of the analyte, either attractive or repulsive. ERLIC (eHILIC) separations need not be isocratic, but the net effect is the reduction of the attraction of a particularly strong polar group, which then requires less strong elution condition... | {
"page_id": 7150276,
"title": "Hydrophilic interaction chromatography"
} |
on the column eluting earlier, and in higher amounts of organic solvent, than if a neutral polar HILIC surface were used. This also increases their detection sensitivity by negative ion mass spectrometry. == Anionic eHILIC == By analogy to the above, one can use an anion exchange (positively charged) column surface che... | {
"page_id": 7150276,
"title": "Hydrophilic interaction chromatography"
} |
Hexaferrum and epsilon iron (ε-Fe) are synonyms for the hexagonal close-packed (HCP) phase of iron that is stable only at extremely high pressure. A 1964 study at the University of Rochester mixed 99.8% pure α-iron powder with sodium chloride, and pressed a 0.5-mm diameter pellet between the flat faces of two diamond a... | {
"page_id": 31595206,
"title": "Hexaferrum"
} |
pressures and temperatures. Figure 2 shows the compressional behaviour of ε-iron at room temperature up to a pressure as would be encountered halfway through the outer core of the Earth; there are no points at pressures lower than approximately 6 GPa, because this allotrope is not thermodynamically stable at low pressu... | {
"page_id": 31595206,
"title": "Hexaferrum"
} |
Niklaus Gerber (8 June 1850 – 9 February 1914) was a Swiss dairy chemist and industrialist. He was born in 1850 in Thun, Switzerland. He attended the University of Bern and University of Zurich, studied chemistry in Paris and Munich and spent 2 years at the Swiss-American Milk Co. in Little Falls, New York. == Biograph... | {
"page_id": 19077833,
"title": "Niklaus Gerber"
} |
Excited state intramolecular proton transfer (ESIPT) is a process in which photoexcited molecules relax their energy through tautomerization by transfer of protons. Some kinds of molecules could have different minimum-energy tautomers in different electronic states, and if the molecular structure of minimum-energy taut... | {
"page_id": 54270667,
"title": "Excited state intramolecular proton transfer"
} |
The molecular formula C20H29NO (molar mass: 299.45 g/mol, exact mass: 299.2249 u) may refer to: Gemazocine (R-15,497) Ibazocine 2-Propanoyl-3-(4-isopropylphenyl)-tropane | {
"page_id": 35592908,
"title": "C20H29NO"
} |
A fraction in chemistry is a quantity collected from a batch of a substance in a fractionating separation process. In such a process, a mixture is separated into fractions, which have compositions that vary according to a gradient. A fraction can be defined as a group of chemicals that have similar boiling points. A co... | {
"page_id": 1907405,
"title": "Fraction (chemistry)"
} |
The Meyer–Schuster rearrangement is the chemical reaction described as an acid-catalyzed rearrangement of secondary and tertiary propargyl alcohols to α,β-unsaturated ketones if the alkyne group is internal and α,β-unsaturated aldehydes if the alkyne group is terminal. == Mechanism == The reaction proceeds by three maj... | {
"page_id": 8002251,
"title": "Meyer–Schuster rearrangement"
} |
product in another step). The authors used the Meyer–Schuster rearrangement because they wanted to convert a hindered ketone to an alkene without destroying the rest of their molecule. == History == The reaction is named after Kurt Meyer and Kurt Schuster. Reviews have been published by Swaminathan and Narayan, == Refe... | {
"page_id": 8002251,
"title": "Meyer–Schuster rearrangement"
} |
Fétizon oxidation is the oxidation of primary and secondary alcohols utilizing the compound silver(I) carbonate absorbed onto the surface of celite also known as Fétizon's reagent first employed by Marcel Fétizon in 1968. It is a mild reagent, suitable for both acid and base sensitive compounds. Its great reactivity wi... | {
"page_id": 39328460,
"title": "Fétizon oxidation"
} |
and xylene are extremely non-polar and further acceleration of the reaction can be achieved through the use of the more non-polar heptane. The solvent is also typically refluxed to drive the reaction with heat and remove the water generated by the reaction through azeotropic distillation. Steric hindrance of the hydrog... | {
"page_id": 39328460,
"title": "Fétizon oxidation"
} |
of lactols in the presence of other alcohols. This also allows for a classic use of Fétizon's reagent to form lactones from a primary diol. By oxidizing one of the alcohols to an aldehyde, the second alcohol equilibrates with the aldehyde to form a lactol which is reacted quickly with more Fétizon's reagent to trap the... | {
"page_id": 39328460,
"title": "Fétizon oxidation"
} |
Fétizon's reagent. However, oxidative carbon-carbon bond cleavage may also occur. == Applications == Since its discovery as a useful method of oxidation, Fétizon's reagent has been used in the total synthesis of numerous molecules such as (±)-bukittinggine. Fétizon's reagent has also been employed extensively in the st... | {
"page_id": 39328460,
"title": "Fétizon oxidation"
} |
In chemistry, the trigonal prismatic molecular geometry describes the shape of compounds where six atoms, groups of atoms, or ligands are arranged around a central atom, defining the vertices of a triangular prism. The structure commonly occurs for d0, d1 and d2 transition metal complexes with covalently-bound ligands ... | {
"page_id": 35855057,
"title": "Trigonal prismatic molecular geometry"
} |
Thripobius semiluteus is a species of parasitic wasp. It has been introduced as a biological control of Heliothrips haemorrhoidalis, greenhouse thrips, in Southern California avocado orchards. == References == | {
"page_id": 72882898,
"title": "Thripobius semiluteus"
} |
Pieter Hendrik van Cittert (30 May 1889, Gouda – 8 October 1959, Utrecht) was a Dutch physicist and science historian. He was born in Gouda, Netherlands, to Benjamin Pieter van Cittert and Petronella Antonia Huber, and died on October 8, 1959, in Utrecht. His achievements include proving the van Cittert–Zernike theorem... | {
"page_id": 39656146,
"title": "Pieter Hendrik van Cittert"
} |
The molecular formula C5H9N3 (molar mass: 111.15 g/mol, exact mass: 111.0796 u) may refer to: Betazole (also called ametazole) Histamine | {
"page_id": 12262106,
"title": "C5H9N3"
} |
Within molecular and cell biology membrane ruffling (also known as cell ruffling) is the formation of a motile cell surface that contains a meshwork of newly polymerized actin filaments. It can also be regarded as one of the earliest structural changes observed in the cell. The GTP-binding protein Rac is the regulator ... | {
"page_id": 16063197,
"title": "Membrane ruffling"
} |
This article lists the largest law firms in the United States by total number of attorneys. The table is also sortable by total number of partners, associates, and total revenue. == See also == List of largest law firms by revenue List of largest United States-based law firms by profits per partner List of largest Unit... | {
"page_id": 57481949,
"title": "List of largest United States–based law firms by head count"
} |
Naum Natanovich (Nokhim Sanalevich) Meiman (Russian: Нау́м Ната́нович (Но́хим Са́нелевич) Ме́йман, 12 May 1912, Bazar, Ukraine – 31 March 2001, Tel Aviv) was a Soviet mathematician, and dissident. He is known for his work in complex analysis, partial differential equations, and mathematical physics, as well as for his ... | {
"page_id": 30874335,
"title": "Naum Meiman"
} |
by the KGB, who also bugged his telephone and searched his home. In 1982, Naum Meiman and Andrei Dmitrievich Sakharov published a letter in defence of Yuri Fyodorovich Orlov. Meiman also struggled for the right of his wife Inna Meiman-Kitrossky to go to the USA for medical treatment since she had been diagnosed with ca... | {
"page_id": 30874335,
"title": "Naum Meiman"
} |
Convective momentum transport usually describes a vertical flux of the momentum of horizontal winds or currents. That momentum is carried like a non-conserved flow tracer by vertical air motions in convection. In the atmosphere, convective momentum transport by small but vigorous (cumulus type) cloudy updrafts can be u... | {
"page_id": 13310687,
"title": "Convective momentum transport"
} |
Bulletin of the Lebedev Physics Institute (Russian: Краткие сообщения по физике, Kratkue Soobsheniya po fisike) is a peer-reviewed scientific journal of physics. The journal was established in 1970, and is published by the Lebedev Physical Institute (in Russian) a monthly basis. Springer publishes an English translatio... | {
"page_id": 15145697,
"title": "Bulletin of the Lebedev Physics Institute"
} |
Hangxiety, short for hangover anxiety, is the colloquial term that refers to the anxiety some people experience during a hangover following alcohol consumption. It describes the sense of worry, stress, and unease that can occur alongside the physical symptoms of a hangover, such as headache, nausea, and fatigue. Hangxi... | {
"page_id": 77404898,
"title": "Hangxiety"
} |
An ecological metacommunity is a set of interacting communities which are linked by the dispersal of multiple, potentially interacting species. The term is derived from the field of community ecology, which is primarily concerned with patterns of species distribution, abundance and interactions. Metacommunity ecology c... | {
"page_id": 18881256,
"title": "Metacommunity"
} |
essentially equivalent in their competitive and dispersal abilities, and local and regional composition and abundance are determined primarily by stochastic demographic processes and dispersal limitation. The neutral perspective was recently popularized by Stephen P. Hubbell following his groundbreaking work on the uni... | {
"page_id": 18881256,
"title": "Metacommunity"
} |
In biology, metamerism is the phenomenon of having a linear series of body segments fundamentally similar in structure, though not all such structures are entirely alike in any single life form because some of them perform special functions. In animals, metameric segments are referred to as somites or metameres. In pla... | {
"page_id": 21830377,
"title": "Metamerism (biology)"
} |
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