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Anala Mons is a volcano on Venus. It is named after Anala, a Hindu fertility goddess. The feature was originally named Anala Corona. It is located at 11.0°N 14.1°E, in a region called the Sappho Patera quadrangle where numerous other volcanic features can be found.
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Stabilizer (chemistry) In industrial chemistry, a stabilizer is a chemical that is used to prevent degradation. Heat and light stabilizers are added to plastics and elastomers because they ensure safe processing and protect products against aging and weathering. The trend is towards fluid systems, pellets, and increased use of masterbatches. There are monofunctional, bifunctional, and polyfunctional stabilizers. In economic terms the most important product groups on the market for stabilizers are compounds based on calcium (calcium-zinc and organo-calcium), lead, and tin stabilizers as well as liquid and light stabilizers (HALS, benzophenone, benzotriazole). Cadmium-based stabilizers largely vanished in the last years due to health and environmental concerns. Some kinds of stabilizers are: In foods, stabilizers prevent spoilage. Classes of food stabilizers include "emulsifiers, thickeners and gelling agents, foam stabilizers, humectants, anticaking agents, and coating agents."
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Sonochemistry In chemistry, the study of sonochemistry is concerned with understanding the effect of ultrasound in forming acoustic cavitation in liquids, resulting in the initiation or enhancement of the chemical activity in the solution. Therefore, the chemical effects of ultrasound do not come from a direct interaction of the ultrasonic sound wave with the molecules in the solution. The influence of sonic waves travelling through liquids was first reported by Robert Williams Wood (1868–1955) and Alfred Lee Loomis (1887–1975) in 1927. The experiment was about the frequency of the energy that it took for sonic waves to "penetrate" the barrier of water. He came to the conclusion that sound does travel faster in water, but because of the water's density compared to earth's atmosphere it was incredibly hard to get the sonic waves to couple their energy into the water. Due to the sudden density change, much of the energy is lost, similar to shining a flashlight towards a piece of glass; some of the light is transmitted into the glass, but much of it is lost to reflection outwards. Similarly with an air-water interface, almost all of the sound is reflected off the water, instead of being transmitted into it. After much research they decided that the best way to disperse sound into the water was to make loud noises into the water by creating bubbles that were made at the same time as the sound. One of the easier ways that they put sound into the water was they simply yelled
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Sonochemistry <nowiki></nowiki> Another issue was the ratio of the amount of time it took for the lower frequency waves to penetrate the bubbles walls and access the water around the bubble, compared to the time from that point to the point on the other end of the body of water. But despite the revolutionary ideas of this article it was left mostly unnoticed. experienced a renaissance in the 1980s with the advent of inexpensive and reliable generators of high-intensity ultrasound, most based around piezoelectric elements. Sound waves propagating through a liquid at ultrasonic frequencies have wavelengths many times longer than the molecular dimensions or the bond length between atoms in the molecule. Therefore, the sound wave cannot directly affect the vibrational energy of the bond, and can therefore not directly increase the internal energy of a molecule. Instead, sonochemistry arises from acoustic cavitation: the formation, growth, and implosive collapse of bubbles in a liquid. The collapse of these bubbles is an almost adiabatic process, thereby resulting in the massive build-up of energy inside the bubble, resulting in extremely high temperatures and pressures in a microscopic region of the sonicated liquid. The high temperatures and pressures result in the chemical excitation of any matter within or very near the bubble as it rapidly implodes
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Sonochemistry A broad variety of outcomes can result from acoustic cavitation including sonoluminescence, increased chemical activity in the solution due to the formation of primary and secondary radical reactions, and increased chemical activity through the formation of new, relatively stable chemical species that can diffuse further into the solution to create chemical effects (for example, the formation of hydrogen peroxide from the combination of two hydroxyl radicals following the dissociation of water vapor within collapsing bubbles when water is exposed to ultrasound). Upon irradiation with high intensity sound or ultrasound, acoustic cavitation usually occurs. Cavitation – the formation, growth, and implosive collapse of bubbles irradiated with sound — is the impetus for sonochemistry and sonoluminescence. Bubble collapse in liquids produces enormous amounts of energy from the conversion of kinetic energy of the liquid motion into heating the contents of the bubble. The compression of the bubbles during cavitation is more rapid than thermal transport, which generates a short-lived localized hot-spot. Experimental results have shown that these bubbles have temperatures around 5000 K, pressures of roughly 1000 atm, and heating and cooling rates above 10 K/s. These cavitations can create extreme physical and chemical conditions in otherwise cold liquids. With liquids containing solids, similar phenomena may occur with exposure to ultrasound
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Sonochemistry Once cavitation occurs near an extended solid surface, cavity collapse is nonspherical and drives high-speed jets of liquid to the surface. These jets and associated shock waves can damage the now highly heated surface. Liquid-powder suspensions produce high velocity interparticle collisions. These collisions can change the surface morphology, composition, and reactivity. Three classes of sonochemical reactions exist: homogeneous sonochemistry of liquids, heterogeneous sonochemistry of liquid-liquid or solid–liquid systems, and, overlapping with the aforementioned, sonocatalysis (the catalysis or increasing the rate of a chemical reaction with ultrasound). Sonoluminescence is a consequence of the same cavitation phenomena that is responsible for homogeneous sonochemistry. The chemical enhancement of reactions by ultrasound has been explored and has beneficial applications in mixed phase synthesis, materials chemistry, and biomedical uses. Because cavitation can only occur in liquids, chemical reactions are not seen in the ultrasonic irradiation of solids or solid–gas systems. For example, in chemical kinetics, it has been observed that ultrasound can greatly enhance chemical reactivity in a number of systems by as much as a million-fold; effectively acting to activate heterogeneous catalysts
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Sonochemistry In addition, in reactions at liquid-solid interfaces, ultrasound breaks up the solid pieces and exposes active clean surfaces through microjet pitting from cavitation near the surfaces and from fragmentation of solids by cavitation collapse nearby. This gives the solid reactant a larger surface area of active surfaces for the reaction to proceed over, increasing the observed rate of reaction. , While the application of ultrasound often generates mixtures of products, a paper published in 2007 in the journal "Nature" described the use of ultrasound to selectively affect a certain cyclobutane ring-opening reaction. Atul Kumar has reported multicomponent reaction Hantzsch ester synthesis in Aqueous Micelles using ultrasound. Some water pollutants, especially chlorinated organic compounds, can be destroyed sonochemically. can be performed by using a bath (usually used for ultrasonic cleaning) or with a high power probe, called an ultrasonic horn, which funnels and couples a piezoelectric element's energy into the water, concentrated at one (typically small) point. can also be used to weld metals which are not normally feasible to join, or form novel alloys on a metal surface. This is distantly related to the method of calibrating ultrasonic cleaners using a sheet of aluminium foil and counting the holes. The holes formed are a result of microjet pitting resulting from cavitation near the surface, as mentioned previously
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Sonochemistry Due to the aluminium foil's thinness and weakness, the cavitation quickly results in fragmentation and destruction of the foil.
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Classes of metals Class A metals are metals that form hard acids. Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium, and the lanthanides, would rather bond with fluorine than iodine. They form stable products with hard bases, which are bases with ionic bonds. They target molecules such as phospholipids, nucleic acids, and ATP. Class B metals are metals that form soft acids. Soft acids are acids with relatively covalent bonds. These metals, such as lead, gold, palladium, platinum, mercury, and rhodium, would rather bond with iodine than fluorine. They form stable products with soft bases, which are bases with covalent bonds. The IUPAC Gold Book provides a more general definition of a class (a) metal ion as "A metal ion that combines preferentially with ligands containing ligating atoms that are the lightest of their Periodic Group", and a class (b) metal ion as one "that combines preferentially with ligands containing ligating atoms other than the lightest of their Periodic Group."
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Hans Daniel Johan Wallengren (8 June 1823 – 25 October 1894) was a Swedish entomologist. He was born in Lund.
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Magnetotellurics (MT) is an electromagnetic geophysical method for inferring the earth's subsurface electrical conductivity from measurements of natural geomagnetic and geoelectric field variation at the Earth's surface. Investigation depth ranges from 300 m below ground by recording higher frequencies down to 10,000 m or deeper with long-period soundings. Proposed in Japan in the 1940s, and France and the USSR during the early 1950s, MT is now an international academic discipline and is used in exploration surveys around the world. Commercial uses include hydrocarbon (oil and gas) exploration, geothermal exploration, carbon sequestration, mining exploration, as well as hydrocarbon and groundwater monitoring. Research applications include experimentation to further develop the MT technique, long-period deep crustal exploration, deep mantle probing, and earthquake precursor prediction research. The magnetotelluric technique was introduced independently by Japanese scientists in the 1940s (Hirayama, Rikitake), Russian geophysicist Andrey Nikolayevich Tikhonov in 1950 and the French geophysicist Louis Cagniard. With advances in instrumentation, processing and modelling, MT has become one of the most important tools in deep Earth research. Since first being created in the 1950s, magnetotelluric sensors, receivers and data processing techniques have followed the general trends in electronics, becoming less expensive and more capable with each generation
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Magnetotellurics Major advances in MT instrumentation and technique include the shift from analog to digital hardware, the advent of remote referencing, GPS time-based synchronization, and 3D data acquisition and processing. For hydrocarbon exploration, MT is mainly used as a complement to the primary technique of reflection seismology exploration. While seismic imaging is able to image subsurface structure, it cannot detect the changes in resistivity associated with hydrocarbons and hydrocarbon-bearing formations. MT does detect resistivity variations in subsurface structures, which can differentiate between structures bearing hydrocarbons and those that do not. At a basic level of interpretation, resistivity is correlated with different rock types. High-velocity layers are typically highly resistive, whereas sediments – porous and permeable – are typically much less resistive. While high-velocity layers are an acoustic barrier and make seismic ineffective, their electrical resistivity means the magnetic signal passes through almost unimpeded. This allows MT to see deep beneath these acoustic barrier layers, complementing the seismic data and assisting interpretation. 3-D MT survey results in Uzbekistan (32 x 32 grid of soundings) have guided further seismic mapping of a large known gas-bearing formation with complex subsurface geology
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Magnetotellurics China National Petroleum Corporation (CNPC) and Nord-West Ltd use onshore MT more than any other oil company in the world, conducting thousands of MT soundings for hydrocarbon exploration and mapping throughout the globe. MT is used for various base metals (e.g. nickel) and precious metals exploration, as well as for kimberlite mapping. INCO's 1991 proof-of-concept study in Sudbury, Ontario, Canada sensed a 1750-meter-deep nickel deposit. Falconbridge followed with a feasibility study in 1996 that accurately located two Ni-Cu mineralized zones at about 800 m and 1350 m depth. Since then, both major and junior mining companies are increasingly using MT and audio-magnetotellurics (AMT) for both brownfields and greenfields exploration. Significant MT mapping work has been done on areas of the Canadian Shield. Diamond exploration, by detecting kimberlites, is also a proven application. MT geothermal exploration measurements allow detection of resistivity anomalies associated with productive geothermal structures, including faults and the presence of a cap rock, and allow for estimation of geothermal reservoir temperatures at various depths. Dozens of MT geothermal exploration surveys have been completed in Japan and the Philippines since the early 1980s, helping to identify several hundred megawatts of renewable power at places such as the Hatchobaru plant on Kyushu and the Togonang plant on Leyte
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Magnetotellurics Geothermal exploration with MT has also been done in the United States, Iceland, New Zealand, Hungary, China, Ethiopia, Indonesia, Peru, Australia, and India. MT is also used for groundwater exploration and mapping, hydrocarbon reservoir monitoring, deep investigation (100 km) of the electrical properties of the bedrock for high-voltage direct current (HVDC) transmission systems, carbon dioxide sequestration, and other environmental engineering applications (e.g. nuclear blast site monitoring and nuclear waste disposal site monitoring). MT has been used to investigate the distribution of silicate melts in the Earth's mantle and crust; large investigations have focused on the continental US (National Science Foundation EarthScope MT Program), the East Pacific Rise and the Tibetan Plateau. Other research work aims to better understand the plate-tectonic processes in the highly complex three-dimensional region formed by the collision of the African and European plates. Fluctuations in the MT signal may be able to predict the onset of seismic events. Stationary MT monitoring systems have been installed in Japan since April 1996, providing a continuous recording of MT signals at the Wakuya Station (previously at the Mizusawa Geodetic Observatory) and the Esashi Station of the Geographical Survey Institute of Japan (GSIJ). These stations measure fluctuations in the Earth's electromagnetic field that correspond with seismic activity
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Magnetotellurics The raw geophysical time-series data from these monitoring stations is freely available to the scientific community, enabling further study of the interaction between electromagnetic events and earthquake activity. The MT time series data from the GSIJ earthquake monitoring stations is available online at https://web.archive.org/web/20100225080738/http://vldb.gsi.go.jp/sokuchi/geomag/menu_03/mt_data-e.html Additional MT earthquake precursor monitoring stations in Japan are located in Kagoshima, in Sawauchi, and on Shikoku. Similar stations are also deployed in Taiwan on Penghu Island, as well as in the Fushan Reserve on the island of Taiwan proper. POLARIS is a Canadian research program investigating the structure and dynamics of the Earth's lithosphere and the prediction of earthquake ground motion. Solar energy and lightning cause natural variations in the earth's magnetic field, inducing electric currents (known as telluric currents) under the Earth's surface."' Different rocks, sediments and geological structures have a wide range of different electrical conductivities. Measuring electrical resistivity allows different materials and structures to be distinguished from one another and can improve knowledge of tectonic processes and geologic structures. The Earth's naturally varying electric and magnetic fields are measured over a wide range of magnetotelluric frequencies from 10,000 Hz to 0.0001 Hz (10,000 s)
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Magnetotellurics These fields are due to electric currents flowing in the Earth and the magnetic fields that induce these currents. The magnetic fields are produced mainly by the interaction between the solar wind and the magnetosphere. In addition, worldwide thunderstorm activity causes magnetic fields at frequencies above 1 Hz. Combined, these natural phenomena create strong MT source signals over the entire frequency spectrum. The ratio of the electric field to magnetic field provides simple information about subsurface conductivity. Because the skin effect phenomenon affects the electromagnetic fields, the ratio at higher frequency ranges gives information on the shallow Earth, whereas deeper information is provided by the low-frequency range. The ratio is usually represented as both apparent resistivity as a function of frequency and phase as a function of frequency. A subsurface resistivity model is then created using this tensor. MT measurements can investigate depths from about 300 m down to hundreds of kilometers, though investigations in the range of 500 m to 10,000 m are typical. Greater depth requires measuring lower frequencies, which in turn requires longer recording times. Very deep, very long-period measurements (mid-crust through upper mantle depths), may require recordings of several days to weeks or more to obtain satisfactory data quality. Horizontal resolution of MT mainly depends on the distance between sounding locations- closer sounding locations increase the horizontal resolution
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Magnetotellurics Continuous profiling (known as Emap) has been used, with only meters between the edges of each telluric dipole. Vertical resolution of MT mainly depends on the frequency being measured, as lower frequencies have greater depths of penetration. Accordingly, vertical resolution decreases as depth of investigation increases. Magnetic fields in the frequency range of 1 Hz to approximately 20 kHz are part of the audio-magnetotelluric (AMT) range. These are parallel to the Earth surface and move towards the Earth's centre. This large frequency band allows for a range of depth penetration from several metres to several kilometres below the Earth's surface. Due to the nature of magnetotelluric source, the waves generally fluctuate in amplitude height. Long recording times are needed to ascertain usable reading due to the fluctuations and the low signal strength. Generally, the signal is weak between 1 and 5 kHz, which is a crucial range in detecting the top 100 m of geology. The magnetotelluric method is also used in marine environments for hydrocarbon exploration and lithospheric studies. Due to the screening effect of the electrically conductive sea water, a usable upper limit of the spectrum is around 1 Hz. Two-dimensional surveys consist of a longitudinal profile of MT soundings over the area of interest, providing two-dimensional "slices" of subsurface resistivity
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Magnetotellurics Three-dimensional surveys consist of a loose grid pattern of MT soundings over the area of interest, providing a more sophisticated three-dimensional model of subsurface resistivity. Audio-magnetotellurics (AMT) is a higher-frequency magnetotelluric technique for shallower investigations. While AMT has less depth penetration than MT, AMT measurements often take only about one hour to perform (but deep AMT measurements during low-signal strength periods may take up to 24 hours) and use smaller and lighter magnetic sensors. Transient AMT is an AMT variant that records only temporarily during periods of more intense natural signal (transient impulses), improving signal-to-noise-ratio at the expense of strong linear polarization. CSEM controlled source electro-magnetic is a deep-water offshore variant of controlled source audio magnetotellurics; CSEM is the name used in the offshore oil and gas industry. and for onshore exploration mostly Lotem is used in Russia, China the USA and Europe Onshore CSEM / CSAMT may be effective where electromagnetic cultural noise (e.g. power lines, electric fences) present interference problems for natural-source geophysical methods. An extensive grounded wire (2 km or more) has currents at a range of frequencies (0.1 Hz to 100 kHz) passed through it. The electric field parallel to the source and the magnetic field which is at right angles are measured
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Magnetotellurics The resistivity is then calculated, and the lower the resistivity, the more likely there is a conductive target (graphite, nickel ore or iron ore). CSAMT is also known in the oil and gas industry as onshore controlled source electromagnetics (Onshore CSEM). An offshore variant of MT, the marine magnetotelluric (MMT) method, uses instruments and sensors in pressure housings deployed by ship into shallow coastal areas where water is less than 300 m deep. A derivative of MMT is offshore single-channel measurement of the vertical magnetic field only (the Hz, or "tipper"), which eliminates the need for telluric measurements and horizontal magnetic measurements. While the theory is sound and many case histories exist, commercial systems are available from KMS Technologies (https://kmstechnologies.com/). Furthermore, any such system would require a solution providing for the precise orientation and stabilization of the magnetic sensor. This usually not an issue since 3 component magnetometers often include accelerometers. MT exploration surveys are done to acquire resistivity data which can be interpreted to create a model of the subsurface. Data is acquired at each sounding location for a period of time (overnight soundings are common), with physical spacing between soundings dependent on the target size and geometry, local terrain constraints and financial cost
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Magnetotellurics Reconnaissance surveys can have spacings of several kilometres, while more detailed work can have 200 m spacings, or even adjacent soundings (dipole-to-dipole). The HSE impact of MT exploration is relatively low because of light-weight equipment, natural signal sources, and reduced hazards compared to other types of exploration (e.g. no drills, no explosives, and no high currents). Remote Reference is an MT technique used to account for cultural electrical noise by acquiring simultaneous data at more than one MT station. This greatly improves data quality, and may allow acquisition in areas where the natural MT signal is difficult to detect because of man-made EM interference. A typical full suite of MT equipment (for a "five component" sounding) consists of a receiver instrument with five sensors: three magnetic sensors (typically induction coil sensors), and two telluric (electric) sensors. For long-period MT (frequencies below approximately 1–10 Hz), the three discrete magnetic field sensors can typically be replaced with a single compact triaxial fluxgate magnetometer. In many situations, only the telluric sensors will be used, and magnetic data borrowed from other nearby soundings to reduce acquisition costs. A complete five-component set of MT equipment can be backpack-carried by a small field team (2 to 4 persons) or carried by a light helicopter (such as the MD Helicopters MD 500), allowing deployment in remote and rugged areas
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Magnetotellurics Most MT equipment is capable of reliable operation over a wide range of environmental conditions, with ratings of typically −25 °C to +55 °C, from dry desert to high-humidity (condensing) and temporary full immersion. Post-acquisition processing is required to transform raw time-series data into frequency-based inversions. The resulting output of the processing program is used as the input for subsequent interpretation. Processing may include the use of remote reference data or local data only. Processed MT data is modelled using various techniques to create a subsurface resistivity map, with lower frequencies generally corresponding to greater depth below ground. Anomalies such as faults, hydrocarbons, and conductive mineralization appear as areas of higher or lower resistivity from surrounding structures. For interpretation (inversion) of magnetotelluric data a number of software are used (WinGlink, Geotools MT, ZondMT2D). MT instrumentation design and construction is a specialized international activity, with only a small number of companies and scientific organizations having the necessary expertise and technology. Three companies supply most of the commercial-use world market: two in the United States,KMS Technologies Zonge International, Inc.), one in Canada; Phoenix Geophysics, Ltd.), and two in Germany (Metronix Messgeraete und Elektronik GmbH) and KMS Technologies GmbH https://kmstechnologies.com/Files/Flyer%20for%20website/KMS_brochure_website.pdf
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Magnetotellurics High power CSEM array systems above 100 KVA for hydrocarbon and geothermal expploration are manufactured by KMS Technologies, USA. Government agencies and smaller companies producing MT instrumentation for internal use include Vega Geophysics, Ltd. in Russia and the Russian Academy of Sciences (SPbF IZMIRAN); and the National Space Research Institute of Ukraine. Geometrics, Inc. of San Jose, California USA produces a high-frequency, hybrid-source AMT system combining both natural fields and a high-frequency (1 to 70 kHz) transmitter, as well as a multi-channel distributed network CSAMT instrument. </ref>== References == replace with https://kmstechnologies.com/Files/Flyer%20for%20website/KMS_brochure_website.pdf
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Edgar D. Zanotto Edgar Dutra Zanotto is a materials engineer and professor at the Federal University of Sao Carlos (UFSCar) in Brazil. He currently teaches glass related subjects for both undergraduate and post-graduate students and he is the head of the Vitreous Materials Laboratory (LaMaV). He is a recipient of the 2010 TWAS Prize. In May 1998, Zanotto wrote an article in the "American Journal of Physics" relating to the false notion that observations of thick glass on old windows translated to the fact that glass is a liquid. Zanotto sought to calculate the flow of glass and found that at 414 Celsius (777 °F) the glass would move a visible amount in 800 years, yet at room temperature he found that it would take glass 10,000 trillion times the age of the earth.
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Ion plating (IP) is a physical vapor deposition (PVD) process that is sometimes called "ion assisted deposition" (IAD) or "ion vapor deposition" (IVD) and is a version of "vacuum deposition". uses concurrent or periodic bombardment of the substrate, and deposits film by atomic-sized energetic particles. Bombardment prior to deposition is used to sputter clean the substrate surface. During deposition the bombardment is used to modify and control the properties of the depositing film. It is important that the bombardment be continuous between the cleaning and the deposition portions of the process to maintain an atomically clean interface. In ion plating the energy, flux and mass of the bombarding species along with the ratio of bombarding particles to depositing particles are important processing variables. The depositing material may be vaporized either by evaporation, sputtering (bias sputtering), arc vaporization or by decomposition of a chemical vapor precursor chemical vapor deposition (CVD). The energetic particles used for bombardment are usually ions of an inert or reactive gas, or, in some cases, ions of the condensing film material ("film ions"). can be done in a plasma environment where ions for bombardment are extracted from the plasma or it may be done in a vacuum environment where ions for bombardment are formed in a separate "ion gun". The latter ion plating configuration is often called Ion Beam Assisted Deposition (IBAD)
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Ion plating By using a reactive gas or vapor in the plasma, films of compound materials can be deposited. is used to deposit hard coatings of compound materials on tools, adherent metal coatings, optical coatings with high densities, and conformal coatings on complex surfaces. The ion plating process was first described in the technical literature by Donald M. Mattox of Sandia National Laboratories in 1964.
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Spectator ion A spectator ion is an ion that exists as a reactant and a product in a chemical equation. A spectator ion can, therefore, be observed in the reaction of aqueous solutions of sodium carbonate and copper(II) sulfate but does not affect the equilibrium: The Na and SO ions are spectator ions since they remain unchanged on both sides of the equation. They simply "watch" the other ions react, hence the name. They are present in total ionic equations to balance the charges of the ions. Whereas the Cu and CO ions combine to form a precipitate of solid CuCO. In reaction stoichiometry, spectator ions are removed from a complete ionic equation to form a net ionic equation. For the above example this yields: So: 2Na + CO + Cu + SO → 2Na + SO + CuCO (Where x = Spectator ion) concentration only affects the Debye length. In contrast, Potential Determining Ions, whose concentrations affect surface potential (by surface chemical reactions) as well the Debye length. A net ionic equation ignores the spectator ions that were part of the original equation. Therefore, the total ionic reaction is different from the net reaction.
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Radioisotope piezoelectric generator A radioisotope piezoelectric generator converts energy stored in the radioactive material directly into motion to generate electricity by the repeated deformation of a piezoelectric material. This approach creates a high-impedance source and, unlike chemical batteries, the devices will work at a very wide range of temperatures. A piezoelectric cantilever is mounted directly above a base of the radioactive isotope nickel-63. All of the radiation emitted as the millicurie-level nickel-63 thin film decays is in the form of beta radiation, which consists of electrons. As the cantilever accumulates the emitted electrons, it builds up a negative charge at the same time that the isotope film becomes positively charged. The beta particles essentially transfer electronic charge from the thin film to the cantilever. The opposite charges cause the cantilever to bend toward the isotope film. Just as the cantilever touches the thin-film isotope, the charge jumps the gap. That permits current to flow back onto the isotope, equalizing the charge and resetting the cantilever. As long as the isotope is decaying - a process that can last for decades - the tiny cantilever will continue its up-and-down motion. As the cantilever directly generates electricity when deformed, a charge pulse is released each time the cantilever cycles. Radioactive isotopes can continue to release energy over periods ranging from weeks to decades. The half-life of nickel-63, for example, is over 100 years
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Radioisotope piezoelectric generator Thus, a battery using this isotope might continue to supply useful energy for at least half that time. Researchers have demonstrated devices with about 7% efficiency with high frequencies of 120 Hz to low-frequency (every three hours) self-reciprocating actuators.
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Tip growth is an extreme form of polarised growth of living cells that results in an elongated cylindrical cell morphology with a rounded tip at which the growth activity takes place. occurs in algae (e.g., "Acetabularia acetabulum"), fungi (hyphae) and plants (e.g. root hairs and pollen tubes). is a process that has many similarities in diverse walled cells such as pollen tubes, root hairs, and hyphae. Fungal hyphae extend continuously at their extreme tips, where enzymes are released into the environment and where new wall materials are synthesised. The rate of tip extension can be extremely rapid - up to 40 micrometres per minute. It is supported by the continuous movement of materials into the tip from older regions of the hyphae. So, in effect, a fungal hypha is a continuously moving mass of protoplasm in a continuously extending tube. This unique mode of growth - apical growth - is the hallmark of fungi, and it accounts for much of their environmental and economic significance.
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Mice Galaxies NGC 4676, or the Mice Galaxies, are two spiral galaxies in the constellation Coma Berenices. About 290 million light-years away, they began the process of colliding and merging. Their name refers to the long tails produced by tidal action—the relative difference between gravitational pulls on the near and far parts of each galaxy—known here as a galactic tide. It is a possibility that both galaxies, which are members of the Coma cluster, have experienced collision, and will continue colliding until they coalesce. The colors of the galaxy are peculiar. In NGC 4676A a core with some dark markings is surrounded by a bluish white remnant of spiral arms. The tail is unusual, starting out blue and terminating in a more yellowish color, despite the fact that the beginning of each arm in virtually every spiral galaxy starts yellow and terminates in a bluish color. NGC 4676B has a yellowish core and two arcs; arm remnants underneath are bluish as well. The galaxies were photographed in 2002 by the Hubble Space Telescope. In the background of the Mice Galaxies, there are at least 3300 galaxies, at distances up to 13 billion light-years.
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NGC 1532 NGC 1532, also known as Haley's Coronet, is an edge-on barred spiral galaxy located approximately 50 million light-years from the Solar System in the constellation Eridanus. The galaxy was discovered by James Dunlop on 29 October 1826. One supernova, SN 1981A, has been recorded in the galaxy. is one of many edge-on spiral galaxies that possesses a box-shaped bulge. This is an indication that the bulge is actually a bar. Such bars are easy to detect in face-on galaxies, where the structures can be identified visually. In inclined galaxies such as this one, however, careful analyses are needed to distinguish between bulges and bar structures. may possess several dwarf companion galaxies. The galaxy is clearly interacting with one of these galaxies, the amorphous dwarf galaxy NGC 1531. The tidal forces from this interaction have created unusual plumes above the disk of NGC 1532. is also an outlying member of the Fornax Cluster.
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Spectral bands are part of optical spectra of polyatomic systems, including condensed materials, large molecules, etc. Each line corresponds to one level in the atom splits in the molecules. When the number of atoms is large, one gets a continuum of energy levels, the so-called "spectral bands". They are often labeled in the same way as the monatomic lines. The bands may overlap. In general, the energy spectrum can be given by a density function, describing the number of energy levels of the quantum system for a given interval. have constant density, and when the bands overlap, the corresponding densities are added. Band spectra is the name given to a group of lines that are closely spaced and arranged in a regular sequence that appears to be a band. It is a colored band, separated by dark spaces on the two sides and arranged in a regular sequence. In one band, there are various sharp and wider color lines, that are closer on one side and wider on other. The intensity in each band falls off from definite limits and indistinct on the other side. In complete band spectra, there is a number lines in a band. This spectra is produced when the emitting substance is in the molecular state. Therefore, they are also called molecular spectra. It is emitted by a molecule in vacuum tube, C-arc core with metallic salt. The band spectrum is the combination of many different spectral lines, resulting from molecular vibrational, rotational, and electronic transition. Spectroscopy studies spectral bands for astronomy and other purposes.
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Fresnel (unit) A Fresnel is a unit of frequency equal to 10 s. It was occasionally used in the field of spectroscopy, but its use has been superseded by "terahertz" (with the identical value 10 hertz). It is named for Augustin-Jean Fresnel the physicist whose expertise in optics led to the creation of Fresnel lenses.
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https://en.wikipedia.org/wiki?curid=3200841
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Phoenicochroite Phoenicochroite, also known as melanochroite, is a lead chromate mineral with formula PbOCrO. It forms striking orange red crystals. It was first discovered in 1839 in Beryozovskoye deposit, Urals, Russia. It is named from the Greek word φοίυικος for "deep red" and χρόα for "color," in allusion to its color.
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https://en.wikipedia.org/wiki?curid=3217470
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Drug development is the process of bringing a new pharmaceutical drug to the market once a lead compound has been identified through the process of drug discovery. It includes preclinical research on microorganisms and animals, filing for regulatory status, such as via the United States Food and Drug Administration for an investigational new drug to initiate clinical trials on humans, and may include the step of obtaining regulatory approval with a new drug application to market the drug. Broadly, the process of drug development can be divided into preclinical and clinical work. New chemical entities (NCEs, also known as new molecular entities or NMEs) are compounds that emerge from the process of drug discovery. These have promising activity against a particular biological target that is important in disease. However, little is known about the safety, toxicity, pharmacokinetics, and metabolism of this NCE in humans. It is the function of drug development to assess all of these parameters prior to human clinical trials. A further major objective of drug development is to recommend the dose and schedule for the first use in a human clinical trial ("first-in-human" [FIH] or First Human Dose [FHD], previously also known as "first-in-man" [FIM]). In addition, drug development must establish the physicochemical properties of the NCE: its chemical makeup, stability, and solubility
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https://en.wikipedia.org/wiki?curid=3218783
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Drug development Manufacturers must optimize the process they use to make the chemical so they can scale up from a medicinal chemist producing milligrams, to manufacturing on the kilogram and ton scale. They further examine the product for suitability to package as capsules, tablets, aerosol, intramuscular injectable, subcutaneous injectable, or intravenous formulations. Together, these processes are known in preclinical and clinical development as "chemistry, manufacturing, and control" (CMC). Many aspects of drug development focus on satisfying the regulatory requirements of drug licensing authorities. These generally constitute a number of tests designed to determine the major toxicities of a novel compound prior to first use in humans. It is a legal requirement that an assessment of major organ toxicity be performed (effects on the heart and lungs, brain, kidney, liver and digestive system), as well as effects on other parts of the body that might be affected by the drug (e.g., the skin if the new drug is to be delivered through the skin). Increasingly, these tests are made using "in vitro" methods (e.g., with isolated cells), but many tests can only be made by using experimental animals to demonstrate the complex interplay of metabolism and drug exposure on toxicity. The information is gathered from this preclinical testing, as well as information on CMC, and submitted to regulatory authorities (in the US, to the FDA), as an Investigational New Drug (IND) application
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https://en.wikipedia.org/wiki?curid=3218783
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Drug development If the IND is approved, development moves to the clinical phase. Clinical trials involve three or four steps: The process of defining characteristics of the drug does not stop once an NCE begins human clinical trials. In addition to the tests required to move a novel drug into the clinic for the first time, manufacturers must ensure that any long-term or chronic toxicities are well-defined, including effects on systems not previously monitored (fertility, reproduction, immune system, among others). They must also test the compound for its potential to cause cancer (carcinogenicity testing). If a compound emerges from these tests with an acceptable toxicity and safety profile, and the company can further show it has the desired effect in clinical trials, then the NCE portfolio of evidence can be submitted for marketing approval in the various countries where the manufacturer plans to sell it. In the United States, this process is called a "new drug application" or NDA. Most NCEs fail during drug development, either because they have unacceptable toxicity or because they simply do not have the intended effect on the targeted disease as shown in clinical trials. A trend toward the collection of biomarker and genetic information from clinical trial participants, and increasing investment by companies in this area, led by 2018 to fully half of all drug trials collecting this information, the prevalence reaching above 80% among oncology trials
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https://en.wikipedia.org/wiki?curid=3218783
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Drug development One 2010 study assessed both capitalized and out-of-pocket costs for bringing a single new drug to market as about US$1.8 billion and $870 million, respectively. A median cost estimate of 2015-16 trials for development of 10 anti-cancer drugs was US$648 million. In 2017, the median cost of a pivotal trial across all clinical indications was $19 million. The average cost for a pivotal trial to demonstrate its equivalence or superiority to an existing approved drug was $347 million. The full cost of bringing a new drug (i.e., new chemical entity) to market – from discovery through clinical trials to approval – is complex and controversial. Typically, companies spend tens to hundreds of millions of U.S. dollars. One element of the complexity is that the much-publicized final numbers often not only include the out-of-pocket expenses for conducting a series of Phase I-III clinical trials, but also the "capital costs" of the long period (10 or more years) during which the company must cover out-of-pocket costs for preclinical drug discovery. In an analysis of the drug development costs for 98 companies over a decade, the average cost per drug developed and approved by a single-drug company was $350 million. But for companies that approved between eight and 13 drugs over 10 years, the cost per drug went as high as $5.5 billion, due mainly to geographic expansion for marketing and ongoing costs for Phase IV trials and continuous monitoring for safety
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https://en.wikipedia.org/wiki?curid=3218783
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Drug development Alternatives to conventional drug development have the objective for universities, governments, and the pharmaceutical industry to collaborate and optimize resources. The nature of a drug development project is characterised by high attrition rates, large capital expenditures, and long timelines. This makes the valuation of such projects and companies a challenging task. Not all valuation methods can cope with these particularities. The most commonly used valuation methods are risk-adjusted net present value (rNPV), decision trees, real options, or comparables. The most important value drivers are the cost of capital or discount rate that is used, phase attributes such as duration, success rates, and costs, and the forecasted sales, including cost of goods and marketing and sales expenses. Less objective aspects like quality of the management or novelty of the technology should be reflected in the cash flows estimation. Candidates for a new drug to treat a disease might, theoretically, include from 5,000 to 10,000 chemical compounds. On average about 250 of these show sufficient promise for further evaluation using laboratory tests, mice and other test animals. Typically, about ten of these qualify for tests on humans. A study conducted by the Tufts Center for the Study of Drug Development covering the 1980s and 1990s found that only 21.5 percent of drugs that started Phase I trials were eventually approved for marketing. In the time period of 2006 to 2015, the success rate was 9.6%
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https://en.wikipedia.org/wiki?curid=3218783
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Drug development The high failure rates associated with pharmaceutical development are referred to as the "attrition rate" problem. Careful decision making during drug development is essential to avoid costly failures. In many cases, intelligent programme and clinical trial design can prevent false negative results. Well-designed, dose-finding studies and comparisons against both a placebo and a gold-standard treatment arm play a major role in achieving reliable data. Novel initiatives include partnering between governmental organizations and industry, such as the European "Innovative Medicines Initiative". The US Food and Drug Administration created the ""Critical Path Initiative"" to enhance innovation of drug development, and the "Breakthrough Therapy" designation to expedite development and regulatory review of candidate drugs for which preliminary clinical evidence shows the drug candidate may substantially improve therapy for a serious disorder.
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https://en.wikipedia.org/wiki?curid=3218783
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Mechanical impedance is a measure of how much a structure resists motion when subjected to a harmonic force. It relates forces with velocities acting on a mechanical system. The mechanical impedance of a point on a structure is the ratio of the force applied at a point to the resulting velocity at that point. is the inverse of mechanical admittance or mobility. The mechanical impedance is a function of the frequency formula_1 of the applied force and can vary greatly over frequency. At resonant frequencies, the mechanical impedance will be lower, meaning less force is needed to cause a structure to move at a given velocity. A simple example of this is pushing a child on a swing. For the greatest swing amplitude, the frequency of the pushes must be near the resonant frequency of the system. formula_2 Where, formula_3 is the force vector, formula_4 is the velocity vector, formula_5 is the impedance matrix and formula_1 is the angular frequency. is the ratio of a potential (e.g. force) to a flow (e.g. velocity) where the arguments of the real (or imaginary) parts of both increase linearly with time. Examples of potentials are: force, sound pressure, voltage, temperature. Examples of flows are: velocity, volume velocity, current, heat flow. Impedance is the reciprocal of mobility. If the potential and flow quantities are measured at the same point then impedance is referred as driving point impedance; otherwise, transfer impedance.
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https://en.wikipedia.org/wiki?curid=3219545
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Homonuclear molecule Homonuclear molecules, or homonuclear species, are molecules composed of only one type of element. Homonuclear molecules may consist of various numbers of atoms, depending on the element's properties. Some elements form molecules of more than one size. The most familiar homonuclear molecules are diatomic, meaning they consist of two atoms, though not all diatomic molecules are homonuclear. Homonuclear diatomic molecules include hydrogen (H), oxygen (O), nitrogen (N) and all of the halogens. Ozone (O) is a common triatomic homonuclear molecule. Homonuclear tetratomic molecules include arsenic (As) and phosphorus (P). Allotropes are different chemical forms of the same element (not containing any other element). In that sense, allotropes are all homonuclear. Many elements have multiple allotropic forms. In addition to the most common form of gaseous oxygen, O, and ozone, there are other allotropes of oxygen. Sulfur forms several allotropes containing different numbers of sulfur atoms, including diatomic, triatomic, hexatomic and octatomic (S, S, S, S) forms, though the first three are rare. The element carbon is known to have a number of homonuclear molecules, including diamond and graphite.
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https://en.wikipedia.org/wiki?curid=3222200
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Solvay S.A. Solvay is a Belgian chemical company founded in 1863, with its head office in Neder-Over-Heembeek, Brussels, Belgium. In 2015, it realized €12.4 billion in revenues, €2.336 billion of REBITDA, 43% of its sales in emerging high-growth countries, 90% of its sales in markets where it is ranked among the top three manufacturers. With 145 sites, Solvay employs 30,900 people in 53 countries. Founded in 1863 by Ernest Solvay and his brother Alfred Solvay to produce sodium carbonate by the Solvay process, the company has diversified into two main sectors of activity: chemicals and plastics. Before World War I, Solvay was the largest multinational company in the world. It was formerly also active in pharmaceuticals, but agreed to sell that entire division to Abbott Labs for €4.5 billion in September 2009, a deal completed in February 2010. In April 2011, the firm agreed to the €3.4 billion acquisition of French-based chemicals company Rhodia which was completed in September 2011. Since January 2012, the new Solvay is listed on the NYSE Euronext in Paris and joined the CAC 40 index in September 2012. Solvay is historically listed on the NYSE Euronext in Brussels and part of BEL20 index. Following its integration with Rhodia, the Committee of Executive Members at Solvay reorganised its various business units into five segments – Consumer Chemicals, Advanced Materials, Performance Chemicals, Functional Polymers and Corporate & Business Services, effective from 2013
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https://en.wikipedia.org/wiki?curid=3224745
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Solvay S.A. The company is a supporter of the Solvay Conferences that were started by Ernest Solvay in 1911. On December 3, 2015, Solvay launched a share issue sent to existing shareholders, completing funding for the $5.5 billion purchase of Cytec Industries Inc. The company's head office is located in Brussels, Belgium. It was previously in Ixelles, Brussels Solvay's United States subsidiary, Solvay America, Inc., is based in Houston, Texas. Solvay is a main partner of Solar Impulse and has contributed research and development resources to their solar powered airplane project. That aircraft conducted its first test flight on 3 December 2009, and since then has made solar-powered flights from Switzerland to Spain and Morocco in 2012. Currently, Solar Impulse II is attempting a round the world flight. Fuel cell technology SolviCore, a joint venture by Umicore and Solvay in the field of fuel cells is already pre-marketing membrane-electrode assemblies for different types of fuel cells for portable or mobile use. New generation lithium batteries for hybrid vehicles components make use of Solvay fluorinated polymers inorder to reduce carbon dioxide emissions. Soil remediation Novosol: sodium bicarbonate-based process for treating and recovering mineral residues contaminated with heavy metals. Renewable feedstock Development and industrialization of proprietary Epicerol process for manufacturing epichlorhydrin from natural glycerin.
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https://en.wikipedia.org/wiki?curid=3224745
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Sedimentary organic matter includes the organic carbon component of sediments and sedimentary rocks. The organic matter is usually a component of sedimentary material even if it is present in low abundance (usually lower than 1%). Petroleum (or oil) and natural gas are particular examples of "sedimentary organic matter". Coals and bitumen shales are examples of sedimentary rocks rich in "sedimentary organic matter". Organic matter is essentially synthesized from mineral carbon (CO) by autotroph organisms living at the boundaries between the geosphere, the atmosphere and the biosphere.
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https://en.wikipedia.org/wiki?curid=3226147
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Trend type forecast In aviation meteorology, a trend type forecast (TTF), also known simply as a trend, is a weather forecast written by a person on location at a major airport or military base. A TTF is a professionally considered forecast for weather over a two-hour period, and is based on an actual weather report, such as a METAR or SPECI and appended to the end of it. A TTF is similar to or sometimes in addition to a TAF, a terminal aerodrome forecast, but during the TTF's validity period is considered superior to a TAF. In this example the METAR indicates it is from EGXE (RAF Leeming) at 1150 UTC on Day 6. The observation follows (see METAR for explanation), with the Trend added to the end of the observation. The Trend reads TEMPO 6000 SHRA SCT020 WHT i.e. Temporary deterioration to 6 km visibility in a moderate rain shower with scattered at 2000 ft, colour state White.
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https://en.wikipedia.org/wiki?curid=3229408
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David Ashton (botanist) David Hungerford Ashton OAM (6 July 1927 – 22 November 2005) was an Australian botanist and ecologist. He was the world expert on "Eucalyptus regnans" forests, claimed to be the most important timber species in Australia. Ashton was born in Melbourne. He received his Bachelor of Science in 1949, and a PhD in 1957. He taught for thirty years at the University of Melbourne, from 1962 to 1992, influencing several generations of Victorian botanists and foresters. His professional expertise ranged from angiosperms, pteridophytes, bryophytes, lichens and fungi. He was also able to synthesise many biological problems ecologically, especially in Mountain Ash forests including geology, plant and animal species interactions, the effects of fire and climate, insect and seed dispersal. He wrote more than 200 scientific articles in over 20 publications. Since 2000, 'The David Ashton Biodiversity and Ecosystems Award' has been awarded annually for the best Victorian ecological research. He was awarded the Medal of the Order of Australia in 2001, "For service to the science of plant ecology, particularly in the areas of forest regeneration, conservation and management."
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https://en.wikipedia.org/wiki?curid=3230759
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Pressure experiment Pressure experiments are experiments performed at pressures lower or higher than atmospheric pressure, called low-pressure experiments and high-pressure experiments, respectively. are necessary because substances behave differently at different pressures. For example, water boils at a lower temperature at lower pressures. The equipment used for pressure experiments depends on whether the pressure is to be increased or decreased and by how much. A vacuum pump is used to remove the air out of a vacuum vessel for low-pressure experiments. High-pressures can be created with a piston-cylinder apparatus, up to () and . The piston is shifted with hydraulics, decreasing the volume inside the confining cylinder and increasing the pressure. For higher pressures, up to , a multi-anvil cell is used and for even higher pressures the diamond anvil cell. The diamond anvil cell is used to create extremely high pressures, as much as a million atmospheres (), though only over a small area. The current record is , but the sample size is confined to the order of tens of micrometres ().
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https://en.wikipedia.org/wiki?curid=3232652
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Hudson Seaway The was a major seaway of North America during the Cretaceous Period some 75 million years ago. It is named after the Hudson Bay, which currently occupies much of its extent. Although not as extensive as the Western Interior Seaway, which divided North America into eastern and western landmasses (Appalachia and Laramidia, respectively), the had major impacts on climate and migration routes by dividing the eastern half of the continent into two (Appalachia and Franklinia). Greenland was more permanently separated, by the foundered rift that created the Labrador Seaway.
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https://en.wikipedia.org/wiki?curid=3236678
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String background In theoretical physics, a string background refers to the set of classical values of quantum fields in spacetime that correspond to classical solutions of string theory. Such a background is associated with geometry that solves Einstein's field equations (with higher order corrections) or their generalizations and with the values of other fields. These fields may encode the information about the shape of the hidden dimensions; the size of various electromagnetic fields and their generalizations; the values of fluxes; and the presence of additional objects such as D-branes and orientifold planes. The full physics of string theory can always be thought of as a system of infinitely many quantum fields expanded around a given string background.
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https://en.wikipedia.org/wiki?curid=3241907
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Thermotunnel cooling is similar to thermionic emission cooling in that fast moving electrons carry heat across a gap but cannot return due to a voltage difference. The problem with using thermal electrons to carry heat is the fact that, due to the high work function of metals, which are the only practical emitters, the lowest cooling temperate is around 600 °C - clearly not useful except in the most unusual applications. avoids this problem by making the gap narrow enough that electrons can tunnel across the gap, carrying the heat with them. The problem with this approach has been getting two surfaces near enough that they can tunnel over a large area, yet not touch at any point, which would short the device out preventing it from doing any useful cooling.
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https://en.wikipedia.org/wiki?curid=3253617
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Dazhbog Patera is a patera (volcanic caldera) on Jupiter's moon Io. Named after Dažbog in 1979, it has a largest size of approximately 120 km and is located . This volcano is difficult to differentiate from the other volcanoes and geological features in some images of Io. In images from the Voyager spacecraft, this caldera is quite prominent with its dark reddish floor with a darkish halo around the caldera. However, in "Galileo" images it is hard to tell where the volcano is. One would suspect that this would mean that it was inactive. But in July 1998, the Hubble Space Telescope using its NICMOS instrument detected a hotspot at Dazhbog.
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https://en.wikipedia.org/wiki?curid=3254527
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Kratochvílite Kratochvilite is a rare organic mineral formed by combustion of coal or pyritic black shale deposits. It is a hydrocarbon with the formula of either CH or (CH)CH. It is a polymorph of the aromatic hydrocarbon fluorene. It forms white, yellow to brown crystals in the orthorhombic system which occur often as a druzey encrustation. It has a specific gravity of 1.21 and a Mohs hardness of 1 to 2. It was first described from the Nejedly mine in Bohemia, Czech Republic in 1937.
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https://en.wikipedia.org/wiki?curid=3255562
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Diphyodont A diphyodont is any animal with two successive sets of teeth, initially the "deciduous" set and consecutively the "permanent" set. Most mammals are diphyodonts—as to chew their food they need a strong, durable and complete set of teeth. Diphyodonts contrast with polyphyodonts, whose teeth are constantly replaced. Diphyodonts also differ from monophyodonts which are animals who have only one set of teeth that do not change over a long period of growth. In diphyodonts, the number of teeth that are replaced varies from species to species. In humans, a set of twenty deciduous teeth, or "milk teeth", are replaced by a completely new set of thirty-two adult teeth. In some cases hypodontia or hyperdontia occurs, the latter in cleidocranial dysostosis and Gardner's syndrome. In the hare the anterior incisors are not replaced but the posterior smaller incisors are replaced. Not much is known about the developmental mechanisms regulating diphyodont replacement. The house shrew, "Suncus murinus", and the Chinese miniature pig are currently being used to study the diphyodont replacement of the deciduous dentition by replacements and additional permanent teeth. Manatees, elephants and kangaroos differ from most other mammals because they are polyphyodonts.
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https://en.wikipedia.org/wiki?curid=3258651
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Silique A silique or siliqua (plural "siliques" or "siliquae") is a type of fruit (seed capsule) having two fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit it is referred to as a silicle. The outer walls of the ovary (the "valves") usually separate when ripe, then being named "dehiscent", and leaving a persistent partition (the "replum"). "Siliques" are present in many members of the mustard family, Brassicaceae, but some species have "silicles" instead. Some species closely related to plants with true "siliques" have fruits with a similar structure that do not open when ripe; these are usually called "indehiscent siliques" (compare dehiscence).
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https://en.wikipedia.org/wiki?curid=3259539
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Leo II (dwarf galaxy) Leo II (or Leo B) is a dwarf spheroidal galaxy about 690,000 light-years away in the constellation Leo. It is one of 24 known satellite galaxies of the Milky Way. Leo II is thought to have a core radius of 178 ± 13 pc and a tidal radius of 632 ± 32 pc. It was discovered in 1950 by Robert George Harrington and Albert George Wilson, from the Mount Wilson and Palomar Observatories in California. In 2007 a team of 15 scientists observed Leo II through the 8.2 meter Subaru optical-infrared telescope in Mauna Kea, Hawaii. Over 2 nights, 90 minutes of exposures were taken and 82,252 stars were detected down to a visible magnitude of 26. They found that Leo II consists largely of metal-poor older stars, a sign that it has survived the galactic cannibalism under which massive galaxies (e.g., the Milky Way) consume smaller galaxies to attain their extensive size. Observation at ESO estimates Leo II's mass to be (2.7 ± 0.5)×10 M.
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https://en.wikipedia.org/wiki?curid=3264593
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CHAMP (satellite) Challenging Minisatellite Payload (CHAMP) was a German satellite launched July 15, 2000 from Plesetsk, Russia and was used for atmospheric and ionospheric research, as well as other geoscientific applications, such as GPS radio occultation. CHAMP was managed by Potsdam (GFZ). The spacecraft is the first application of Astrium's "Flexbus" platform; GRACE was the second. A heavily modified version flew as the GOCE mission. CHAMP completed its mission and re-entered the Earth's atmosphere on 19 September 2010 after 10 years (design life: five years). The mission was judged as being successful by the involved scientists.
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https://en.wikipedia.org/wiki?curid=3266098
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Gastón Pons Muzzo (circa 1922 – January 6, 2004) was a Peruvian chemist. He was born in Tacna, Peru and joined National University of San Marcos staff in the 1960s to lecture general chemistry laboratory at the Department of Chemistry. He also was known for his teaching of physical chemistry and for his accompanying textbook. He was elected as dean in 1964 and remained in office until 1967. He was elected as president of Chemical Society of Peru between 1974 and 1977 and was rector magnificus of the university. In 1985, when his term ended, he was awarded by then Peru's official secretary of treasury, "Miguel Ángel Cusiánovich", in recognition of his role as rector. Before his retirement from National University of San Marcos, he was appointed to another term in Peru's chemical society from 1988 to 1989. During the late 1990s, he was elected president of the commission which eventually established ""María Inmaculada de Magdalena University"", but health problems led him retire. He died on January 6, 2004 in Lima, Peru at the age of 81.
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https://en.wikipedia.org/wiki?curid=3270305
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Bergen School of Meteorology The "Bergen School of Meteorology" is a school of thought which is the basis for much of modern weather forecasting. Founded by the meteorologist Prof. Vilhelm Bjerknes and his younger colleagues in 1917, the Bergen School attempts to define the motion of the atmosphere by means of the mathematics of interactions between hydro- and thermodynamics, some of which had originally been discovered or explained by Bjerknes himself, thus making mathematical predictions regarding the weather possible by systematic data analysis. Much of the work was done at the Geophysical Institute, University of Bergen, in Bergen, Norway. The Bergen School was crucial in the early development and operationalization of numerical weather forecasting in the 1940s and 1950s, which was largely a cooperation between Scandinavian and US researchers. In this development, extant meteorological theories were synthesized. Due to the vast amount of calculations necessary for producing viable forecasts, the mathematical models were adapted to computer programs. The cross-atlantic cooperations was also important to the development of the Bergen School and the Norwegian meteorology community
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Schizocarp A schizocarp is a dry fruit that, when mature, splits up into mericarps. There are different definitions:
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https://en.wikipedia.org/wiki?curid=3289776
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Mrinal Kumar Das Gupta (1 September 1923 – 28 November 2005, Kolkata) was an Indian astronomer. He was born in erstwhile Barishal district in present-day Bangladesh. He received his B.Sc and M.Sc degrees in Physics from Dhaka University in 1944 and 1945 respectively. Later he joined the department of Radio Physics and Electronics of the University of Calcutta as a researcher. In 1954, he obtained his Ph.D. from the University of Manchester. Later he became the head of the department of the Institute of Radio Physics and Electronics at Calcutta University. Das Gupta worked with Robert Hanbury Brown and Roger Jennison, in building the first intensity interferometers at radio wavelength in the early 1950s and measured the apparent angular structures of two radio sources, Cygnus A and Cassiopeia A. Das Gupta was elected as a "Fellow of the National Academy of Science" in 1974 by the Indian National Science Academy, New Delhi and as a "Fellow of the Academy of Science" by the Indian Academy of Sciences, Bangalore. He died on 28 November 2005 in Kolkata.
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https://en.wikipedia.org/wiki?curid=3291366
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Fritz Konrad Ernst Zumpt (1908–1985) was a German entomologist who worked mainly in Africa . He is best known for his work on Diptera and the associations between insects and African mammals, as well as for his work on myiasis. Amongst Zumpt’s works are:
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NGC 4414 is an unbarred spiral galaxy about 62 million light-years away in the constellation Coma Berenices. It is a flocculent spiral galaxy, with short segments of spiral structure but without the dramatic well-defined spiral arms of a grand design spiral. In 1974 a supernova, SN 1974G, was observed and was the only supernova in this galaxy to be recorded until June 7, 2013 when SN 2013df was discovered at Magnitude 14. It was imaged by the Hubble Space Telescope in 1995, as part of the HST's main mission to determine the distance to galaxies, and again in 1999 as part of the Hubble Heritage project. It has been part of an ongoing effort to study its Cepheid variable stars. The outer arms appear blue due to the continuing formation of young stars and include a possible luminous blue variable with an absolute magnitude of −10. is also a very isolated galaxy without signs of past interactions with other galaxies and despite not being a starburst galaxy shows a high density and richness of gas – both atomic and molecular, with the former extending far beyond its optical disk. is a member of the Coma I Group, a group of galaxies lying physically close to the Virgo Cluster.
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https://en.wikipedia.org/wiki?curid=3292677
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Enzyme replacement therapy (ERT) is a medical treatment which replaces an enzyme that is deficient or absent in the body. Usually, this is done by giving the patient an intravenous (IV) infusion of a solution containing the enzyme. ERT is currently available for some lysosomal storage diseases: Gaucher disease, Fabry disease, MPS I, MPS II (Hunter syndrome), MPS VI and Pompe disease. ERT does not correct the underlying genetic defect, but it increases the concentration of the enzyme that the patient is lacking. ERT has also been used to treat patients with severe combined immunodeficiency (SCID) resulting from an adenosine deaminase deficiency (ADA-SCID). Other treatment options for patients with enzyme or protein deficiencies include substrate reduction therapy, gene therapy, and bone-marrow derived stem cell transplantation.[1] ERT was developed in 1964 by Christian de Duve and Roscoe Brady. Leading work was done on this subject at the Department of Physiology at the University of Alberta by Mark J. Poznansky and Damyanti Bhardwaj, where a model for enzyme therapy was developed using rats. ERT was not used in clinical practice until 1991, after the FDA gave orphan drug approval for the treatment of Gaucher disease with Alglucerase. ERTs were initially manufactured by isolating the therapeutic enzyme from human placenta. The FDA has now approved ERTs that are derived from other human cells, animal cells (i.e. Chinese hamster ovary cells, or CHO cells), and plant cells
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Enzyme replacement therapy Lysosomal storage diseases are fatal group of diseases and a main application of ERT. Lysosomes are cellular organelles that are responsible for the metabolism of many different macromolecules and proteins. They use enzymes to break down macromolecules, which are recycled or disposed. As of 2012, there are 50 lysosomal storage diseases, and more are still being discovered. These disorders arise because of genetic mutations that prevent the production of certain enzymes used in the lysosomes. The missing enzyme often leads to a build-up of the substrate within the body. This can result in a variety of symptoms, many of which are severe and can affect the skeleton, brain, skin, heart, and the central nervous system. Increasing the concentration of the missing enzyme within the body has been shown to improve the body's normal cellular metabolic processes and reduce substrate concentration in the body. ERT has also been successful in treating severe combined immunodeficiency caused by an adenosine deaminase deficiency (ADA-SCID). This is a fatal childhood disease that requires early medical intervention. When the enzyme adenosine deaminase is deficient in the body, the result is a toxic build-up of metabolites that impair lymphocyte development and function. Many ADA deficient children with SCID have been treated with the polyethylene glycol-conjugated adenosine deaminase (PEG-ADA) enzyme. This is a form of ERT that has resulted in healthier, longer lives for patients with ADA-SCID
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Enzyme replacement therapy ERT is administered by IV infusion. Typically, infusions occur every week or every two weeks. For some types of ERT, these infusions can occur as infrequently as every four weeks. ERT is not a cure for lysosomal storage diseases, and it requires lifelong IV infusions of the therapeutic enzyme. This procedure is expensive; in the United States, it may cost over $200,000 annually. The distribution of the therapeutic enzyme in the body (biodistribution) after these IV infusions is not uniform. The enzyme in less available to certain areas in the body, like the bones, lungs, brain. For this reason, many symptoms of lysosomal storage diseases remain untreated by ERT, especially neurological symptoms. Additionally, the efficacy of ERT is often reduced due to an unwanted immune response against the enzyme, which prevents metabolic function. Substrate reduction therapy is another method for treating lysosomal storage diseases. In this treatment, the accumulated compounds are inhibited from forming in the body of a patient suffering from a lysosomal storage disease. The accumulated compounds are responsible for the symptoms of these disorders, and they form via a multi-step biological pathway. Substrate reduction therapy uses a small molecule to interrupt this multi-step pathway and inhibit the biosynthesis of these compounds. This type of treatment is taken orally. It does not induce an unwanted immune response, and a single type of small molecule could be used to treat many lysosomal storage diseases
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Enzyme replacement therapy Substrate reduction therapy is FDA approved and there is at least one treatment available on the market. Gene therapy aims to replace a missing protein in the body through the use of vectors, usually viral vectors. In gene therapy, a gene encoding for a certain protein is inserted into a vector. The vector containing the therapeutic gene is then injected into the patient. Once inside the body the vector introduces the therapeutic gene into host cells, and the protein encoded by the newly inserted gene is then produced by the body's own cells. This type of therapy can correct for the missing protein/enzyme in patients with lysosomal storage diseases. Hematopoietic stem cell (HSC) transplantation is another treatment for lysosomal storage diseases. HSCs are derived from bone-marrow. These cells have the ability to mature into the many cell types that comprise blood, including red blood cells, platelets, and white blood cells. Patients suffering from enzyme deficiencies often undergo HSC transplantations in which HSCs from a healthy donor are injected. This treatment introduces HSCs that regularly produce the deficient enzyme since they have normal metabolic function. This treatment is often used to treat the central nervous system of patients with some lysosomal storage diseases.
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https://en.wikipedia.org/wiki?curid=3295601
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SiGNa chemistry is a type of chemistry in which alkali metals are encapsulated into porous oxides of silica gel in order to reduce their pyrophoric and highly combustible properties while preserving the desirable reduction reactivity of the metals (Dye, et al.). One can deconstruct the term "SiGNa" to derive Si (symbol for silicon), G (gel), and Na (symbol for sodium, a popular alkali metal). was pioneered by Michael Lefenfeld, a PhD student at Columbia University with the help of Dr. James Dye of Michigan State University.
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https://en.wikipedia.org/wiki?curid=3295906
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Background noise or ambient noise is any sound other than the sound being monitored (primary sound). is a form of noise pollution or interference. is an important concept in setting noise levels. Background noises include environmental noises such as water waves, traffic noise, alarms, extraneous speech, bioacoustic noise from animals, and electrical noise from devices such as refrigerators, air conditioning, power supplies, and motors. The prevention or reduction of background noise is important in the field of active noise control. It is an important consideration with the use of ultrasound (e.g. for medical diagnosis or imaging), sonar, and sound reproduction. In astronomy, background noise or cosmic background radiation is electromagnetic radiation from the sky with no discernible source. In information architecture, irrelevant, duplicate or incorrect information may be called background noise. In physics and telecommunication, background signal noise can be detrimental or in some cases beneficial. The study of avoiding, reducing or using signal noise is information theory. In telephony, artificial comfort noise is used as a substitute for natural background noise, to fill in artificial silence created by discontinuous transmission systems using voice activity detection. can also affect concentration.
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https://en.wikipedia.org/wiki?curid=3296057
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Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz, a silicate mineral chemically silicon dioxide. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, but it is has also been mined in Lower Silesia in Poland. Naturally occurring prasiolite has also been found in the Thunder Bay area of Canada. , the only mine producing prasiolite is in Brazil but even that is almost mined out. Most prasiolite sold is used in jewellery settings, where it can substitute for far more expensive precious gemstones. It is a rare stone in nature; artificially produced prasiolite is heat treated amethyst. Most amethyst will turn yellow or orange when heated producing citrine, but some amethyst will turn green when treated. Currently, almost all prasiolite on the market results from a combination of heat treatment and ionizing radiation. Green quartz is sometimes incorrectly called green amethyst, which is not an acceptable name for the material, the proper terminology being prasiolite. It is against Federal Trade Commission Guidelines to call prasiolite "green amethyst". Other names for green quartz are vermarine, greened amethyst, or lime citrine. The word prasiolite literally means "scallion green-colored stone" and is derived from Greek πράσον "prason" meaning "leek" and λίθος "lithos" meaning "stone". The mineral was given its name due to its green-colored appearance. Natural prasiolite is a very light, translucent green
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https://en.wikipedia.org/wiki?curid=3298668
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Prasiolite Darker green quartz is generally the result of artificial treatment.
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https://en.wikipedia.org/wiki?curid=3298668
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Erik Bongcam-Rudloff is a Chilean-born Swedish biologist and computer scientist. He received his doctorate in medical sciences from Uppsala University in 1994. He is Professor of Bioinformatics and the head of SLU-Global Bioinformatics Centre at the Swedish University of Agricultural Sciences. His main research deals with development of bioinformatics solutions for the Life Sciences community. He was the chairman of EMBnet, (2003–2010) a science-based group of collaborating bioinformatics nodes throughout Europe, and a number of nodes outside Europe. He is also the director of SLU-Global Bioinformatics Centre which created eBiotools, eBioX and eBioKit. is also executive board member of: Coordinator of:
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https://en.wikipedia.org/wiki?curid=3300289
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Asbestiform is a crystal habit. It describes a mineral that grows in a fibrous aggregate of high tensile strength, flexible, long, and thin crystals that readily separate. The most common asbestiform mineral is chrysotile, commonly called "white asbestos", a magnesium phyllosilicate part of the serpentine group. Other asbestiform minerals include riebeckite, an amphibole whose fibrous form is known as crocidolite or "blue asbestos", and brown asbestos, a cummingtonite-grunerite solid solution series. The United States Environmental Protection Agency explains that, “In general, exposure may occur only when the asbestos-containing material is disturbed or damaged in some way to release particles and fibers into the air.”
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https://en.wikipedia.org/wiki?curid=3300567
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Natterer compressor A was a type of air compression machine which was used in early experiments in making liquid oxygen (LOX) in the 1870s. A manually operated screw jack was utilized to compress air or other gases up to ~200 atm (~3000 psi). The device was created by Johann Natterer, a student of Adolf Martin Pleischl, for experiments creating liquid carbonic acid.
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https://en.wikipedia.org/wiki?curid=3306344
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Flood forecasting is the use of forecasted precipitation and streamflow data in rainfall-runoff and streamflow routing models to forecast flow rates and water levels for periods ranging from a few hours to days ahead, depending on the size of the watershed or river basin. can also make use of forecasts of precipitation in an attempt to extend the lead-time available. is an important component of flood warning, where the distinction between the two is that the outcome of flood forecasting is a set of forecast time-profiles of channel flows or river levels at various locations, while "flood warning" is the task of making use of these forecasts to tell decisions on warnings of floods. Real-time flood forecasting at regional area can be done within seconds by using the technology of artificial neural network. Effective real-time flood forecasting models could be useful for early warning and disaster prevention.
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https://en.wikipedia.org/wiki?curid=3307613
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Impact ionization is the process in a material by which one energetic charge carrier can lose energy by the creation of other charge carriers. For example, in semiconductors, an electron (or hole) with enough kinetic energy can knock a bound electron out of its bound state (in the valence band) and promote it to a state in the conduction band, creating an electron-hole pair. For carriers to have sufficient kinetic energy a sufficiently large electric field must be applied, in essence requiring a sufficiently large voltage but not necessarily a large current. If this occurs in a region of high electrical field then it can result in avalanche breakdown. This process is exploited in avalanche diodes, by which a small optical signal is amplified before entering an external electronic circuit. In an avalanche photodiode the original charge carrier is created by the absorption of a photon. In some sense, impact ionization is the reverse process to Auger recombination. Avalanche photodiodes (APD) are used in optical receivers before the signal is given to the receiver circuitry the photon is multiplied with the photocurrent and this increases the sensitivity of the receiver since photocurrent is multiplied before encountering of the thermal noise associated with the receiver circuit.
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https://en.wikipedia.org/wiki?curid=3310426
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Harkhebi (ca. 300 BC) was an astronomer who lived in Ptolemaic Egypt during the rule of the Ptolemaic dynasty. He was known as the priest of Selket (the stargazer). He specialized in the treatment of snake bites and scorpion stings. He also kept record of day and night, tracking the rising and setting of the sun. This then predicted he was evident in 1872 B.C. from the temple of Illahun. He may have based many of his observations on earlier Babylonian contributions to astronomy. A funereal statue associated with him is known with an inscription in which he describes himself as an expert on observing stars.. He referred to the planets as "the gods who foretell the future" and claimed to know everything Sirius predicted, but apparently did not write personal horoscopes. predicted the weather patterns of the heliacal risings of the fixed stars. He refers the winds and the omens to his prediction of meteorology. While was observing the north and south motions of the sun and Venus, he concluded that the Babylonians had some affiliation with the weather phenomena in "Enuma Anu Enil." The lunar crater is named after him. Half of the crater is on top of the large walled plain Fabry. This is on the north-northeast side of Fabry. On the other half, the northwest half, lies Vashakidze, a smaller crater than Fabry. And on the southwest is Vestine, and Richardson on the south.
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https://en.wikipedia.org/wiki?curid=3312366
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NGC 1559 is a barred spiral galaxy in the constellation Reticulum. It is also a Seyfert galaxy. Although it was originally thought to be a member of the Dorado Group, subsequent observations have shown that it is in fact not a member of any galaxy group or cluster and does not have any nearby companions. has massive spiral arms and strong star formation. It contains a small bar which is oriented nearly east-west and spans 40″. Its bar and disc are the source of very strong radio emissions. In 2005, a Type 1a supernova, (SN 2005df) was observed. Two other supernovae discovered in were SN 1984J and SN 1986L. All three were discovered by Australian amateur astronomer Robert Evans.
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https://en.wikipedia.org/wiki?curid=3331591
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Reef knoll A reef knoll is a land-based landform that comprises an immense pile of calcareous material that accumulated on a previously existing ancient sea floor. At the time of its accumulation it may have had enough structure from organisms such as sponges to have been free-standing and to withstand the sea currents as material accumulated, and was likely an atoll. Another possibility is the remains of deep water coral. Such structures are thus often fossil-rich. Examples on the Derbyshire/Staffordshire border include Thorpe Cloud and Bunster Hill in southern Dovedale, and also Chrome Hill and Parkhouse Hill at the northern end. These structures are often most clearly seen where the surrounding rocks are much softer and so can be preferentially eroded. All the Derbyshire examples quoted lie at the edge of the limestone areas; Chrome and Parkhouse lie at the divide between limestone and the much softer shale. Examples in the Yorkshire Dales lie on the downthrow side (north) of the Mid Craven Fault. There is one set located around Thorpe (Skelterton, Butter Haw, Stebden, Elbolton, Thorpe Kail, Myra Bank and Hartlington Kail); one set located around Malham (Burns Hill, Cawden, and Wedber); and a set around Settle (High Hill and Scaleber). It was once proposed that in Lancashire, reef knolls could be seen between the villages of Worston and Downham near Clitheroe. Waulsortian mudmound
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https://en.wikipedia.org/wiki?curid=3337617
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Elitzur–Vaidman bomb tester The Elitzur–Vaidman bomb-tester is a quantum mechanics thought experiment that uses interaction-free measurements to verify that a bomb is functional without having to detonate it. It was conceived in 1993 by Avshalom Elitzur and Lev Vaidman. Since their publication, real-world experiments have confirmed that their theoretical method works as predicted. The bomb tester takes advantage of two characteristics of elementary particles, such as photons or electrons: nonlocality and wave-particle duality. By placing the particle in a quantum superposition, it is possible for the experiment to verify that the bomb works "without" triggering its detonation, although there is still a 50% chance that the bomb will detonate in the effort. The bomb test is an interaction-free measurement. The idea of getting information about an object without interacting with it is not a new one. For example, there are two boxes, one of which contains something, the other of which contains nothing. If you open one box and see nothing, you know that the other contains something, without ever opening it. This experiment has its roots in the double-slit experiment and other, more complex concepts which inspired it, including Schrödinger's cat, and Wheeler's delayed-choice experiment. The behavior of elementary particles is very different from what we experience in our macroscopic world. Their observed behavior can be that of a wave or of a particle (see wave–particle duality), their wave-like behavior implies what is called "superposition"
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https://en.wikipedia.org/wiki?curid=3339367
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Elitzur–Vaidman bomb tester In this state, some properties of the particle, for example, its location, are not definite. While in a superposition, any and all possibilities are equally real. So, if the particle could feasibly exist in more than one location, in certain senses that are experimentally useful, it exists in all of them simultaneously. The particle's wave can later be "collapsed" by observing it, at which time its location (or other measured property) at the moment of observation is definite. Information can then be gleaned not only about the actual state of the particle, but also other states or locations in which it "existed" before the collapse. This gleaning of information is possible even if the particle was never factually in any of the particular states or locations that are of interest. Consider a collection of light-sensitive bombs, of which some are duds. When their triggers detect any light, even a single photon, the light is absorbed and the bomb explodes. The triggers on the dud bombs have no sensor, so the photon cannot be absorbed. Thus, the dud bomb will not detect the photon and will not detonate. Is it possible to determine which bombs are functional and which are duds without detonating all of the live ones? A superposition in the bomb tester is created with an angled half-silvered mirror, which allows a photon to either pass through it, or be reflected off it at a 90-degree angle (see figure 3). There is equal probability it will do either. The photon enters a superposition, in which it does both
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https://en.wikipedia.org/wiki?curid=3339367
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Elitzur–Vaidman bomb tester The single particle both passes through, and is reflected off the half-silvered mirror. From that moment on, the single photon exists in two different locations. Along both the upper and lower path, the particle will encounter an ordinary mirror, positioned to redirect the two routes toward one another. They then intersect at a second half-silvered mirror. On the other side, a pair of detectors are placed such that the photon can be detected by either detector, but never by both. It is also possible that it will not be detected by either. Based on this outcome, with a live bomb, there is a 50% chance it will explode, a 25% chance it will be identified as good without exploding and a 25% chance there will be no result. A light-sensitive bomb is placed along the lower path. If the bomb is good, when a photon arrives, it will explode and both will be destroyed. If it is a dud, the photon will pass by unaffected (see figure 4). To understand how this experiment works, it is important to know that the bomb is a kind of observer and that this encounter is a kind of observation. It can therefore collapse the photon's superposition, in which the photon is travelling along both the upper and lower paths. When it reaches the live bomb, or the detectors, however, it can only have been on one or the other
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https://en.wikipedia.org/wiki?curid=3339367
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Elitzur–Vaidman bomb tester But, like the radioactive material in the box with Schrödinger's famous cat, upon its encounter with the half-silvered mirror at the beginning of the experiment, the photon, paradoxically does and does not interact with the bomb. According to the authors, the bomb both explodes and does not explode. This is only in the case of a live bomb, however. In any event, once observed by the detectors, it will have only traveled one of the paths. When two waves collide, the process by which they affect each other is called interference. They can either strengthen each other by "constructive interference", or weaken each other by "destructive interference". This is true whether the wave is in water, or a single photon in a superposition. So even though there is only one photon in the experiment, because of its encounter with the half-silvered mirror, it acts like two. When "it" or "they" are reflected off the ordinary mirrors, it will interfere with itself as if it were two different photons. "But that is only true if the bomb is a dud." A live bomb will absorb the photon when it explodes and there will be no opportunity for the photon to interfere with itself. When it reaches the second half-silvered mirror, if the photon in the experiment is behaving like a particle (in other words, if it is not in a superposition), then it has a fifty-fifty chance it will pass through or be reflected and be detected by one or the other detector. "But that is only possible if the bomb is live
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https://en.wikipedia.org/wiki?curid=3339367
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Elitzur–Vaidman bomb tester " If the bomb "observed" the photon, it detonated and destroyed the photon on the lower path, therefore only the photon that takes the upper path will be detected, either at Detector C or Detector D. Detector D is the key to confirming that the bomb is live. The two detectors and the second half-silvered mirror are precisely aligned with one another. Detector C is positioned to detect the particle if the bomb is a dud and the particle traveled both paths in its superposition and then constructively interfered with itself. Detector D is positioned to detect the photon only in the event of destructive interference—an impossibility (see figure 6). In other words, if the photon is in a superposition at the time it arrives at the second half-silvered mirror, it will always arrive at detector C and never at detector D. If the bomb is live, there is a 50/50 chance that the photon took the upper path. If it "factually" did so, then it "counter-factually" took the lower path (see figure 7). That counter-factual event destroyed that photon and left only the photon on the upper path to arrive at the second half-silvered mirror. At which point it will, again, have a 50/50 chance of passing through it or being reflected off it, and, subsequently, it will be detected at either of the two detectors with the same probability. This is what makes it possible for the experiment to verify the bomb is live without actually blowing it up
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Elitzur–Vaidman bomb tester With a live bomb, there can be three possible outcomes: These correspond with the following conditions of the bomb being tested: If the result is 2, the experiment is repeated. If the photon continues to be observed at C and the bomb does not explode, it can eventually be concluded that the bomb is a dud. With this process 25% of live bombs can be identified without being detonated, 50% will be detonated and 25% remain uncertain. By repeating the process with the uncertain ones, the ratio of identified non-detonated live bombs approaches 33% of the initial population of bombs. See below for a modified experiment that can identify the live bombs with a yield rate approaching 100%. The authors state that the ability to obtain information about the bomb's functionality without ever "touching" it appears to be a paradox. That, they argue, is based on the assumption that there is only a single "real" result. But according to the many-worlds interpretation, each possible state of a particle's superposition is real. The authors therefore argue that the particle does actually interact with the bomb and it does explode, just not in our "world". In 1994, Anton Zeilinger, Paul Kwiat, Harald Weinfurter, and Thomas Herzog actually performed an equivalent of the above experiment, proving interaction-free measurements are indeed possible. In 1996, Kwiat "et al." devised a method, using a sequence of polarising devices, that efficiently increases the yield rate to a level arbitrarily close to one
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https://en.wikipedia.org/wiki?curid=3339367
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Elitzur–Vaidman bomb tester The key idea is to split a fraction of the photon beam into a large number of beams of very small amplitude and reflect all of them off the mirror, recombining them with the original beam afterwards. It can also be argued that this revised construction is simply equivalent to a resonant cavity and the result looks much less shocking in this language; see Watanabe and Inoue (2000). In 2016, Carsten Robens, Wolfgang Alt, Clive Emary, Dieter Meschede, and Andrea Alberti demonstrated that the Elitzur–Vaidman bomb testing experiment can be recast in a rigorous test of the macro-realistic worldview based on the violation of the Leggett–Garg inequality using ideal negative measurements. In their experiment they perform the bomb test with a single atom trapped in a polarization-synthesized optical lattice. This optical lattice enables interaction-free measurements by entangling the spin and position of atoms.
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https://en.wikipedia.org/wiki?curid=3339367
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Hoop Conjecture The hoop conjecture, proposed by Kip Thorne in 1972, states that an imploding object forms a black hole when, and only when, a circular hoop with a specific critical circumference could be placed around the object and rotated about a diameter. The critical circumference is given by: where Thorne calculated the effects of gravitation on objects of different shapes (spheres, and cylinders that are infinite in one direction), and concluded that the object needed to be compressed in all three directions before gravity led to the formation of a black hole. With cylinders, the event horizon was formed when the object could fit inside the hoop described above. The mathematics to prove the same for objects of all shapes was too difficult for him at that time, but he formulated his hypothesis as the hoop conjecture. In 2019 Yan Peng found an analytical proof of the conjecture in the spatially regular static charged fluid sphere spacetime.
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https://en.wikipedia.org/wiki?curid=3339824
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Ernst Friedrich Germar (3 November 1786 – 8 July 1853) was a German professor and director of the Mineralogical Museum at Halle. As well as being a mineralogist he was interested in entomology and particularly in the Coleoptera and Hemiptera. He monographed the heteropteran family Scutelleridae. In 1845, he was elected a foreign member of the Royal Swedish Academy of Sciences. Amongst Germar's publications are: He was also editor of the entomological journal "Zeitschrift für die Entomologie", which was published from 1839 to 1844. Non Coleoptera Deutsches Entomologisches Institut (DEI)
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https://en.wikipedia.org/wiki?curid=3347310
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Maturity (geology) In petroleum geology, the maturity of a rock is a measure of its state in terms of hydrocarbon generation. Maturity is established using a combination of geochemical and basin modelling techniques. Rocks with high total organic carbon, (termed source rocks), will alter under increasing temperature such that the organic molecules slowly mature into hydrocarbons (see diagenesis). Source rocks are therefore broadly categorised as "immature" (no hydrocarbon generation), "sub-mature" (limited hydrocarbon generation), "mature" (extensive hydrocarbon generation) and "overmature" (most hydrocarbons have been generated). The maturity of a source rock can also be used as an indicator of its hydrocarbon "potential". That is, if a rock is sub-mature, then it has a much higher potential to generate further hydrocarbons than one that is overmature.
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https://en.wikipedia.org/wiki?curid=3356530
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Pulsed columns are a type of liquid-liquid extraction equipment; examples of this class of extraction equipment is used at the BNFL plant THORP. Special use in nuclear industries for fuel reprocessing, where spent fuel from reactors is subjected to solvent extraction. A pulsation is created using air by a pulse leg. The feed is aqueous solution containing radioactive solutes, and the solvent used is TBP (Tri-Butyl Phosphate) in suitable hydrocarbon. To create turbulence for dispersion of one phase in other, a mechanical agitator is used in conventional equipments. But, because of radioactivity, and frequent maintenance required for mechanical agitators, pulsing is used in extraction columns.
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https://en.wikipedia.org/wiki?curid=3362237
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Partition equilibrium is a special case of chemical equilibrium. The most common chemical equilibrium systems involve reactants and products in the same phase - either all gases or all solutions. However, it is also possible to get equilibria between substances in different phases, such as two liquids that do not mix (are immiscible). Partition equilibria are described by Nernst's distribution law. For example, ammonia (NH) is soluble in both water (aq) and the organic solvent trichloromethane (CHCl) - two immiscible solvents. If ammonia is first dissolved in water, and then an equal volume of trichloromethane is added, and the two liquids shaken together, the following equilibrium is established: The equilibrium concentrations of ammonia in each layer can be established by titration with standard acid solution. It can thus be determined that K remains constant, with a value of 0.4 in this case. This particular kind of equilibrium constant measures how a substance distributes or partitions itself between two immiscible solvents. It is called the partition coefficient or distribution coefficient. Substances that are ionic or polar are more soluble in water than in non-polar organic solvents and vice versa. chromatography is a type of chromatography that is typically used in gas chromatography (GC) and high performance liquid chromatography (HPLC). The stationary phase in GC is a high boiling liquid bonded to solid surface and the mobile phase is a gas.
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https://en.wikipedia.org/wiki?curid=3362709
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Artificial reproduction is the creation of new life by other than the natural means available to an organism. Examples include artificial insemination, in vitro fertilization, cloning and embryonic splitting, or cleavage. Cutting plants' stems and placing them in compost is also a form of artificial reproduction.
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https://en.wikipedia.org/wiki?curid=3366914
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Magnetorheological finishing (MRF) is a precision surface finishing technology. Optical surfaces are polished in a computer-controlled magnetorheological (MR) finishing slurry. Unlike conventional rigid lap polishing, the MR fluid's shape and stiffness can be magnetically manipulated and controlled in real time. The optic's final surface form and finishing results are predicted through the use of computer algorithms. W.I. Kordonski (2014). "Magnetorheological Fluid-Based High Precision Finishing Technology." Magnetorheology: Advances and Applications, Norman M. Wereley, Ed., RSC Smart Materials, Cambridge, UK, Chapter 11, 261-277. DOI:10.1039/9781849737548-00261
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https://en.wikipedia.org/wiki?curid=3367341
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Adolph Modéer (1738–1799) was a Swedish surveyor, economic historian and naturalist. As a naturalist he was mainly interested in malacology and entomology. He also worked on jellyfish. As an economic historian, he wrote on the history of Sweden's trade. Modéer worked as a surveyor from 1755, and was Secretary of the Medical Society at Stockholm and from 1786 a member of the Royal Swedish Academy of Sciences. His publications as a naturalist were:
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https://en.wikipedia.org/wiki?curid=3368915
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Photoinduced charge separation is the process of an electron in an atom or molecule, being excited to a higher energy level by the absorption of a photon and then leaving the atom or molecule to a nearby electron acceptor. An atom consists of a positively charged nucleus orbited by electrons. The nucleus consists of uncharged neutrons and positively charged protons. Electrons are negatively charged. In the early part of the twentieth century Ernest Rutherford suggested that the electrons orbited the dense central nucleus in a manner analogous to planets orbiting the sun. The centripetal force required to keep the electrons in orbit was provided by the Coulomb force of the protons in the nucleus acting upon the electrons; just like the gravitational force of the sun acting on a planet provides the centripetal force necessary to keep the planet in orbit. This model, although appealing, doesn't hold true in the real world. Synchrotron radiation would cause the orbiting electron to lose orbital energy and spiral inward since the vector quantity of acceleration of the particle multiplied by its mass (the value of the force required to keep the electron in circular motion) would be less than the electrical force the proton applied to the electron. Once the electron spiralled into the nucleus the electron would combine with a proton to form a neutron, and the atom would cease to exist. This model is clearly wrong. In 1913 Niels Bohr refined the Rutherford model by stating that the electrons existed in discrete quantized states called energy levels
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https://en.wikipedia.org/wiki?curid=3370908
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Photoinduced charge separation This meant that the electrons could only occupy orbits at certain energies. The laws of quantum physics apply here, and they don't comply with the laws of classical newtonian mechanics. An electron which is completely free from the atom has an energy of 0 joules (or 0 electronvolts). An electron which is described as being at the "ground state" has an energy which is equal to the ionization energy of the atom. The electron will reside in this energy level under normal circumstances. If a photon of light hits the atom it will be absorbed if, and only if, energy of that photon is equal to the difference between the ground state and another energy level in that atom. This raises the electron to a higher energy level.
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https://en.wikipedia.org/wiki?curid=3370908
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ISO 31-3 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to "mechanics". It is superseded by ISO 80000-4. Its definitions include (note boldfaced symbols mean quantity is a vector):
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https://en.wikipedia.org/wiki?curid=3371466
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ISO 31-4 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to "heat". It is superseded by ISO 80000-5. Its definitions include: Annex A of lists units of heat based on the foot, pound and second and some other units, including the degree Rankine, degree Fahrenheit, British thermal unit and others. Annex B lists conversion factors for three versions of the calorie.
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https://en.wikipedia.org/wiki?curid=3371482
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ISO 31-5 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to "electricity and magnetism". It is superseded by ISO 80000-6. Some of its definitions are below, with values taken from NIST values of the constants:
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https://en.wikipedia.org/wiki?curid=3371491
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ISO 31-6 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to "light and related electromagnetic radiations". It is superseded by ISO 80000-7. Its definitions include:
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https://en.wikipedia.org/wiki?curid=3371516
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