ChemTEB Classification Datasets
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Chemical Classification Datasets for Evaluating Text Embedding Models
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Some inorganic selenide sulfide compounds are also known. Simplest is the material selenium sulfide, which has medicinal properties. It adopt the diverse structures of elemental sulfur but with some S atoms replaced by Se.
Other inorganic selenide sulfide compounds occur as minerals and as pigments. One example is antimony selenosulfide.
The pigment cadmium red consists of cadmium sulfoselenide. It is a solid solution of cadmium sulfide, which is yellow, and cadmium selenide, which is dark brown. It is used as an artist's pigment. Unlike the organic selenosulfides and unlike selenide sulfide itself, no S-Se bond exists in CdSSe or in SbSSe. | 1 | Semiconductor Materials |
In Korean folk medicine, trace elements in the yellow clay and bamboo are thought to make this form of salt more healthy. Historically, has been used as a digestive aid, styptic, disinfectant or dentifrice.
Oriental medicinalist Insan Kim Il-hoon (1909–1992), was (according to his institution) the first to claim that could be used to treat cancer. His other claims are that can be used to treat intestinal inflammation, peptic ulcer disease, dyspepsia, esophageal tumours and more. | 0 | Salts |
Viologens, in their dicationic form, typically undergo two one-electron reductions. The first reduction affords the deeply colored radical cation:
: [V] + e [V]
The radical cations are blue for 4,4-viologens and green for 2,2-derivatives. The second reduction yields a yellow quinoid compounds:
: [V] + e [V]
The electron transfer is fast because the redox process induces little structural change. The redox is highly reversible. These reagents are relatively inexpensive among redox-active organic compounds. They are convenient colorimetric reagents for biochemical redox reactions. | 0 | Salts |
Brine (or briny water) is water with a high-concentration solution of salt (typically sodium chloride or calcium chloride). In diverse contexts, brine may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking (pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization (fresh water recovery). | 0 | Salts |
Cerebos is a brand of salt and, more recently, of other flavourings and nutritional supplements. Ownership of Cerebos brand is divided between Kraft Heinz in Asia Pacific, Australia and New Zealand, Premier Foods in UK, K+S in Western Europe, and Bud Group in South Africa. The product was developed by George Weddell, a Scottish chemist working at the British company Mawson & Swan, and sold under the Cerebos brand by a new partnership, Mawson, Swan & Weddell.
The company Cerebos Ltd was later registered in 1894. At the time of its introduction, salt was sold in large blocks from which the user would scrape what they needed. Free-running salt was a novelty because, left for any length of time, pure sodium chloride crystals would absorb sufficient moisture from the air to cause them to stick together, a phenomenon called caking. Its slogan was "See How It Runs", because the salt contained anti-caking agents. The slogan was echoed in the product branding of a small boy chasing a chicken, a reference to the superstition that birds might be caught by pouring salt onto their tail.
Ernest Shackleton lists Cerebos salt among the few precious stocks taken in the James Caird on his trip with five men from Elephant Island to South Georgia as he attempted to engineer a daring escape from the Antarctic.
From 1923 until the mid 1900s, Cerebos Ltd had a factory at the then 10 Victoria Road, in North Acton, northwest London, UK. The company was purchased by Rank Hovis McDougall (RHM) in 1968, and the site was redeveloped into the Shaftesbury Gardens housing development in the mid 1990's.
Cerebos salt is sold in Western Europe (including France where it is spelt Cérébos), Australia, New Zealand and South Africa. The Australian and New Zealand operations were part of Cerebos Pacific, and now owned by Kraft Heinz which acquired most of its assets from Suntory Holdings in 2018, and includes the well known local brands:
*Greggs (NZ)
*Robert Harris (NZ)
*Bisto (NZ)
*[http://www.cerebosfoodservice.co.nz/food/powdered-beverages/ Raro] (NZ)
*atomic (NZ)
*Whitlock's (NZ)
*L'affare (NZ)
*Bruno Rossi (NZ)
*Gravox (Australia)
*Fountain (Australia)
*Toby Estate (Australia)
*Saxa (Australia)
*Foster Clark's (Australia)
*Mocopan (Australia)
*Asian Home Gourmet (Australia) | 0 | Salts |
Mercury(II) iodide displays thermochromism; when heated above 126 °C (400 K) it undergoes a phase transition, from the red alpha crystalline form to a pale yellow beta form. As the sample cools, it gradually reacquires its original colour. It has often been used for thermochromism demonstrations. A third form, which is orange, is also known; this can be formed by recrystallisation and is also metastable, eventually converting back to the red alpha form. The various forms can exist in a diverse range of crystal structures and as a result mercury(II) iodide possesses a surprisingly complex phase diagram. | 1 | Semiconductor Materials |
Copper(I) oxide or cuprous oxide is the inorganic compound with the formula CuO. It is one of the principal oxides of copper, the other being copper(II) oxide or cupric oxide (CuO). Cuprous oxide is a red-coloured solid and is a component of some antifouling paints. The compound can appear either yellow or red, depending on the size of the particles. Copper(I) oxide is found as the reddish mineral cuprite. | 1 | Semiconductor Materials |
Soapmakers in Naples were members of a guild in the late sixth century (then under the control of the Eastern Roman Empire), and in the eighth century, soap-making was well known in Italy and Spain. The Carolingian capitulary De Villis, dating to around 800, representing the royal will of Charlemagne, mentions soap as being one of the products the stewards of royal estates are to tally. The lands of Medieval Spain were a leading soapmaker by 800, and soapmaking began in the Kingdom of England about 1200. Soapmaking is mentioned both as "women's work" and as the produce of "good workmen" alongside other necessities, such as the produce of carpenters, blacksmiths, and bakers.
In Europe, soap in the 9th century was produced from animal fats and had an unpleasant smell. This changed when olive oil began to be used in soap formulas instead, after which much of Europe's soap production moved to the Mediterranean olive-growing regions. Hard toilet soap was introduced to Europe by Arabs and gradually spread as a luxury item. It was often perfumed. By the 15th century, the manufacture of soap in the Christendom had become virtually industrialized, with sources in Antwerp, Castile, Marseille, Naples and Venice. | 0 | Salts |
All forms of have a layered structure, in which a plane of molybdenum atoms is sandwiched by planes of sulfide ions. These three strata form a monolayer of MoS. Bulk MoS consists of stacked monolayers, which are held together by weak van der Waals interactions.
Crystalline MoS exists in one of two phases, 2H-MoS and 3R-MoS, where the "H" and the "R" indicate hexagonal and rhombohedral symmetry, respectively. In both of these structures, each molybdenum atom exists at the center of a trigonal prismatic coordination sphere and is covalently bonded to six sulfide ions. Each sulfur atom has pyramidal coordination and is bonded to three molybdenum atoms. Both the 2H- and 3R-phases are semiconducting.
A third, metastable crystalline phase known as 1T-MoS was discovered by intercalating 2H-MoS with alkali metals. This phase has trigonal symmetry and is metallic. The 1T-phase can be stabilized through doping with electron donors such as rhenium, or converted back to the 2H-phase by microwave radiation. The 2H/1T-phase transition can be controlled via the incorporation of S vacancies. | 1 | Semiconductor Materials |
The band gap of uranium dioxide is comparable to those of silicon and gallium arsenide, near the optimum for efficiency vs band gap curve for absorption of solar radiation, suggesting its possible use for very efficient solar cells based on Schottky diode structure; it also absorbs at five different wavelengths, including infrared, further enhancing its efficiency. Its intrinsic conductivity at room temperature is about the same as of single crystal silicon.
The dielectric constant of uranium dioxide is about 22, which is almost twice as high as of silicon (11.2) and GaAs (14.1). This is an advantage over Si and GaAs in the construction of integrated circuits, as it may allow higher density integration with higher breakdown voltages and with lower susceptibility to the CMOS tunnelling breakdown.
The Seebeck coefficient of uranium dioxide at room temperature is about 750 µV/K, a value significantly higher than the 270 µV/K of thallium tin telluride (TlSnTe) and thallium germanium telluride (TlGeTe) and of bismuth-tellurium alloys, other materials promising for thermoelectric power generation applications and Peltier elements.
The radioactive decay impact of the U and U on its semiconducting properties was not measured . Due to the slow decay rate of these isotopes, it should not meaningfully influence the properties of uranium dioxide solar cells and thermoelectric devices, but it may become an important factor for VLSI chips. Use of depleted uranium oxide is necessary for this reason. The capture of alpha particles emitted during radioactive decay as helium atoms in the crystal lattice may also cause gradual long-term changes in its properties.
The stoichiometry of the material dramatically influences its electrical properties. For example, the electrical conductivity of UO is orders of magnitude lower at higher temperatures than the conductivity of UO.
Uranium dioxide, like UO, is a ceramic material capable of withstanding high temperatures (about 2300 °C, in comparison with at most 200 °C for silicon or GaAs), making it suitable for high-temperature applications like thermophotovoltaic devices.
Uranium dioxide is also resistant to radiation damage, making it useful for rad-hard devices for special military and aerospace applications.
A Schottky diode of UO and a p-n-p transistor of UO were successfully manufactured in a laboratory. | 1 | Semiconductor Materials |
Dead Sea salt refers to salt and other mineral deposits extracted or taken from the Dead Sea. The composition of this material differs significantly from oceanic salt. | 0 | Salts |
Electron mobility is one important parameter describing semiconductors because it describes the rate at which electrons can travel through the semiconductor. At 40 K, electron mobility ranged from at an antimony concentration of 0 to at an antimony concentration of 7.2%. This is much greater than the electron mobility of other common semiconductors like silicon, which is 1400 cm/V·s at room temperature.
Another important parameter of BiSb is the effective electron mass (EEM), a measure of the ratio of the acceleration of an electron to the force applied to an electron. The effective electron mass is for x = 0.11 and at x = 0.06. This is much less than the electron effective mass in many common semiconductors (1.09 in Si at 300 K, 0.55 in Ge, and 0.067 in GaAs). A low EEM is good for Thermophotovoltaic applications. | 1 | Semiconductor Materials |
Caliche beds can cause problems for agriculture. First, an impermeable caliche layer prevents water from draining properly, which can keep roots from getting enough oxygen. Salts can also build up in the soil due to the lack of drainage. Both of these situations are detrimental to plant growth. Second, the impermeable nature of caliche beds prevents plant roots from penetrating the bed, which limits the supply of nutrients, water, and space so they cannot develop normally. Third, caliche beds can also cause the surrounding soil to be basic. The basic soil, along with calcium carbonate from the caliche, can prevent plants from getting enough nutrients, especially iron. An iron deficiency makes the youngest leaves turn yellow. Soil saturation above the caliche bed can make the condition worse. Its hardness can also make digging for projects such as canals more difficult. | 0 | Salts |
Gallium(III) selenide (GaSe) is a chemical compound. It has a defect sphalerite (cubic form of ZnS) structure. It is a p-type semiconductor
It can be formed by union of the elements. It hydrolyses slowly in water and quickly in mineral acids to form toxic hydrogen selenide gas. The reducing capabilities of the selenide ion make it vulnerable to oxidizing agents. It is advised therefore that it not come into contact with bases. | 1 | Semiconductor Materials |
In 1913 the structure of sodium chloride was determined by William Henry Bragg and William Lawrence Bragg. This revealed that there were six equidistant nearest-neighbours for each atom, demonstrating that the constituents were not arranged in molecules or finite aggregates, but instead as a network with long-range crystalline order. Many other inorganic compounds were also found to have similar structural features. These compounds were soon described as being constituted of ions rather than neutral atoms, but proof of this hypothesis was not found until the mid-1920s, when X-ray reflection experiments (which detect the density of electrons), were performed.
Principal contributors to the development of a theoretical treatment of ionic crystal structures were Max Born, Fritz Haber, Alfred Landé, Erwin Madelung, Paul Peter Ewald, and Kazimierz Fajans. Born predicted crystal energies based on the assumption of ionic constituents, which showed good correspondence to thermochemical measurements, further supporting the assumption. | 0 | Salts |
In combination with 1,2- or 1,3-diamine ligands, CuI catalyzes the conversion of aryl, heteroaryl, and vinyl bromides into the corresponding iodides. NaI is the typical iodide source and dioxane is a typical solvent (see aromatic Finkelstein reaction).
CuI is used as a co-catalyst with palladium catalyst in the Sonogashira coupling.
CuI is used in cloud seeding, altering the amount or type of precipitation of a cloud, or their structure by dispersing substances into the atmosphere which increase water's ability to form droplets or crystals. CuI provides a sphere for moisture in the cloud to condense around, causing precipitation to increase and cloud density to decrease.
The structural properties of CuI allow CuI to stabilize heat in nylon in commercial and residential carpet industries, automotive engine accessories, and other markets where durability and weight are a factor.
CuI is used as a source of dietary iodine in table salt and animal feed. | 1 | Semiconductor Materials |
Dead Sea salt was used by the peoples of Ancient Egypt and it has been utilized in various unguents, skin creams, and soaps since then. | 0 | Salts |
A xanthate is a salt or ester of a xanthic acid. The formula of the salt of xanthic acid is (where R is organyl group and M is usually Na or K). Xanthate also refers to the anion . The formula of a xanthic acid is , such as ethyl xanthic acid, while the formula of an ester of a xanthic acid is , where R and R are organyl groups. The salts of xanthates are also called O-organyl dithioates. The esters of xanthic acid are also called O,S-diorganyl esters of dithiocarbonic acid. The name xanthate is derived from Ancient Greek (xanthos) meaning yellowish or golden', and indeed most xanthate salts are yellow. They were discovered and named in 1823 by Danish chemist William Christopher Zeise. These organosulfur compounds are important in two areas: the production of cellophane and related polymers from cellulose and (in mining) for extraction of certain sulphide bearing ores. They are also versatile intermediates in organic synthesis. | 0 | Salts |
A hyclate () is a pharmaceutical term for hydrochloride hemiethanolate hemihydrate (·HCl·EtOH·HO), e.g. doxycycline hyclate. | 0 | Salts |
In addition to its use as a fertilizer, potassium chloride is important in many industrialized economies, where it is used in aluminium recycling, by the chloralkali industry to produce potassium hydroxide, in metal electroplating, oil-well drilling fluid, snow and ice melting, steel heat-treating, in medicine as a treatment for hypokalemia, and water softening. Potassium hydroxide is used for industrial water treatment and is the precursor of potassium carbonate, several forms of potassium phosphate, many other potassic chemicals, and soap manufacturing. Potassium carbonate is used to produce animal feed supplements, cement, fire extinguishers, food products, photographic chemicals, and textiles. It is also used in brewing beer, pharmaceutical preparations, and as a catalyst for synthetic rubber manufacturing. Also combined with silica sand to produce potassium silicate, sometimes known as waterglass, for use in paints and arc welding electrodes. These non-fertilizer uses have accounted for about 15% of annual potash consumption in the United States. | 0 | Salts |
At least two polymorphs have been characterized by X-ray crystallography. They both feature copper(I) in a characteristic tetrahedral coordination geometry. The sulfur end of the SCN- ligand is triply bridging so that the coordination sphere for copper is CuS3N. | 1 | Semiconductor Materials |
From 1767, potash from wood ashes was exported from Canada. By 1811, 70% of the total 19.6 million lbs of potash imports to Britain came from Canada. Exports of potash and pearl ash reached 43,958 barrels in 1865. There were 519 asheries in operation in 1871. | 0 | Salts |
Brine discharge might lead to an increase in salinity above certain threshold levels that has the potential to affect benthic communities, especially those more sensitive to osmotic pressure, finally having an effect on their abundance and diversity.
However, if appropriate mitigation measures are applied, the potential environmental impacts of discharges from SWRO plants can be correctly minimized. Some examples can be found in countries such as Spain, Israel, Chile or Australia, in which the mitigation measures adopted reduce the area affected by the discharge, guaranteeing a sustainable development of the desalination process without significant impacts on marine ecosystems. When noticeable effects have been detected on the environment surrounding discharge areas, it generally corresponds to old desalination plants in which the correct mitigation measures were not implemented. Some examples can be found in Spain, Australia or Chile, where it has been shown that saline plumes do not exceed values of 5% with respect to the natural salinity of the sea in a radius less than 100 m from the point of discharge when proper measures are adopted. | 0 | Salts |
The figures, in high relief form a circle around the shaft of the elephant tusk, supporting the bowl at top used to hold the salt. The amount and type of decoration indicates that this piece was created in a Benin court. Two of the four male figures are from clearly of a higher rank, probably from a higher class. They are more elaborately carved and shown frontally, while the other two have less ornament and are shown in profile. The men on the front and on the back are dressed with elaborate clothes with a cross necklace, showing they are European Christians. In addition they are wearing hats and holding spears in their left hand.
The style used to carve the ivory piece may be intended to be somewhat grotesque. In Afro-Portuguese ivories there are three African elements that are fundamental to call a piece African art: a focus on the human figure, an enunciation of the parts and a preference for pure geometric forms. Individuals are presented as the main subject in African art usually depicting an important figure like royalty or a deity, this is shown in the ivory salt cellar and other Benin Bronzes. The faces of each man are bigger with their long beards and deep eyes than their body while keeping their proportions in check. The geometry of the pattern of the men's clothing, the socket of the spear is another example where this geometry is repeated. | 0 | Salts |
Although SnO is insoluble in water, it is amphoteric, dissolving in base and acid. "Stannic acid" refers to hydrated tin (IV) oxide, SnO, which is also called "stannic oxide."
Tin oxides dissolve in acids. Halogen acids attack SnO to give hexahalostannates, such as [SnI]. One report describes reacting a sample in refluxing HI for many hours.
:SnO + 6 HI → HSnI + 2 HO
Similarly, SnO dissolves in sulfuric acid to give the sulfate:
:SnO + 2 HSO → Sn(SO) + 2 HO
The latter compound can add additional hydrogen sulfate ligands to give hexahydrogensulfatostannic acid.
SnO dissolves in strong bases to give "stannates," with the nominal formula NaSnO. Dissolving the solidified SnO/NaOH melt in water gives Na[Sn(OH)], "preparing salt," which is used in the dye industry. | 1 | Semiconductor Materials |
These species are classified as both organosulfur and organoselenium compounds. They are hybrids of organic disulfides and organic diselenides. | 1 | Semiconductor Materials |
Caliche () is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions, including in central and western Australia, in the Kalahari Desert, in the High Plains of the western United States, in the Sonoran Desert, Chihuahuan Desert and Mojave Desert of North America, and in eastern Saudi Arabia at Al-Hasa. Caliche is also known as calcrete or kankar (in India). It belongs to the duricrusts. The term is borrowed from Spanish and is originally from the Latin word , meaning lime.
Caliche is generally light-colored, but can range from white to light pink to reddish-brown, depending on the impurities present. It generally occurs on or near the surface, but can be found in deeper subsoil deposits, as well. Layers vary from a few inches to feet thick, and multiple layers can exist in a single location. A caliche layer in a soil profile is sometimes called a K horizon.
In northern Chile and Peru, caliche also refers to mineral deposits that include nitrate salts. Caliche can also refer to various claylike deposits in Mexico and Colombia. In addition, it has been used to describe some forms of quartzite, bauxite, kaolinite, laterite, chalcedony, opal, and soda niter.
A similar material, composed of calcium sulfate rather than calcium carbonate, is called gypcrust. | 0 | Salts |
The lattice energy is the summation of the interaction of all sites with all other sites. For unpolarizable spherical ions, only the charges and distances are required to determine the electrostatic interaction energy. For any particular ideal crystal structure, all distances are geometrically related to the smallest internuclear distance. So for each possible crystal structure, the total electrostatic energy can be related to the electrostatic energy of unit charges at the nearest neighboring distance by a multiplicative constant called the Madelung constant that can be efficiently computed using an Ewald sum. When a reasonable form is assumed for the additional repulsive energy, the total lattice energy can be modelled using the Born–Landé equation, the Born–Mayer equation, or in the absence of structural information, the Kapustinskii equation.
Using an even simpler approximation of the ions as impenetrable hard spheres, the arrangement of anions in these systems are often related to close-packed arrangements of spheres, with the cations occupying tetrahedral or octahedral interstices. Depending on the stoichiometry of the ionic compound, and the coordination (principally determined by the radius ratio) of cations and anions, a variety of structures are commonly observed, and theoretically rationalized by Pauling's rules.
In some cases, the anions take on a simple cubic packing and the resulting common structures observed are:
Some ionic liquids, particularly with mixtures of anions or cations, can be cooled rapidly enough that there is not enough time for crystal nucleation to occur, so an ionic glass is formed (with no long-range order). | 0 | Salts |
Alkaline salts are often the major component of alkaline dishwasher detergent powders.
These salts may include:
*alkali metasilicates
*alkali metal hydroxides
*Sodium carbonate
*Sodium Bicarbonate
Examples of other strongly alkaline salts, include:
*Sodium percarbonate
*Sodium persilicate (?)
*Potassium metabisulfite | 0 | Salts |
Thin films of chromium-doped indium oxide (InCrO) are a magnetic semiconductor displaying high-temperature ferromagnetism, single-phase crystal structure, and semiconductor behavior with high concentration of charge carriers. It has possible applications in spintronics as a material for spin injectors.
Thin polycrystalline films of indium oxide doped with Zn are highly conductive (conductivity ~10 S/m) and even superconductive at liquid helium temperatures. The superconducting transition temperature T depends on the doping and film structure and is below 3.3 K. | 1 | Semiconductor Materials |
A preparation of indium sulfide made with the radioactive In can be used as a lung scanning agent for medical imaging. It is taken up well by lung tissues, but does not accumulate there. | 1 | Semiconductor Materials |
In order to achieve high ionic conductivity, electrochemical measurements are conducted in the presence of excess electrolyte. In water the electrolyte is often a simple salt such as potassium chloride. For measurements in nonaqueous solutions, salts composed of both lipophilic cations and anions are employed, e.g., tetrabutylammonium hexafluorophosphate. Even in such cases potentials are influenced by ion-pairing, an effect that is accentuated in solvents of low dielectric constant. | 0 | Salts |
Reduction of magnetite ore by CO in a blast furnace is used to produce iron as part of steel production process:
Controlled oxidation of FeO is used to produce brown pigment quality γ-FeO (maghemite):
More vigorous calcining (roasting in air) gives red pigment quality α-FeO (hematite): | 1 | Semiconductor Materials |
This oxide of tin has been utilized as a mordant in the dyeing process since ancient Egypt. A German by the name of Kuster first introduced its use to London in 1533 and by means of it alone, the color scarlet was produced there. | 1 | Semiconductor Materials |
While bulk MoS in the 2H-phase is known to be an indirect-band gap semiconductor, monolayer MoS has a direct band gap. The layer-dependent optoelectronic properties of MoS have promoted much research in 2-dimensional MoS-based devices. 2D MoS can be produced by exfoliating bulk crystals to produce single-layer to few-layer flakes either through a dry, micromechanical process or through solution processing.
Micromechanical exfoliation, also pragmatically called "Scotch-tape exfoliation", involves using an adhesive material to repeatedly peel apart a layered crystal by overcoming the van der Waals forces. The crystal flakes can then be transferred from the adhesive film to a substrate. This facile method was first used by Konstantin Novoselov and Andre Geim to obtain graphene from graphite crystals. However, it can not be employed for a uniform 1-D layers because of weaker adhesion of MoS to the substrate (either Si, glass or quartz); the aforementioned scheme is good for graphene only. While Scotch tape is generally used as the adhesive tape, PDMS stamps can also satisfactorily cleave MoS if it is important to avoid contaminating the flakes with residual adhesive.
Liquid-phase exfoliation can also be used to produce monolayer to multi-layer MoS in solution. A few methods include lithium intercalation to delaminate the layers and sonication in a high-surface tension solvent. | 1 | Semiconductor Materials |
In chemistry, a hydrochloride is an acid salt resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base (e.g. an amine). An alternative name is chlorhydrate, which comes from French. An archaic alternative name is muriate, derived from hydrochloric acid's ancient name: muriatic acid. | 0 | Salts |
Aluminium soaps are used as thickening agents, in the production of cosmetics. Other examples include mixed calcium/zinc soaps which are used as heat stabilizer for polyvinyl chloride. Soaps of iron, cobalt and manganese are used as drying agents in paints and varnishes and work by promoting the oxidation and crosslinking of unsaturated oils. | 0 | Salts |
Active tectonics will increase the likelihood of salt structures developing. In the case of extensional tectonics, faulting will both reduce the strength of the overburden and thin it. In an area affected by thrust tectonics, buckling of the overburden layer will allow the salt to rise into the cores of anticlines, as seen in salt domes in the Zagros Mountains and in El Gordo diapir (Coahuila fold-and-thrust belt, NE Mexico).
If the pressure within the salt body becomes sufficiently high it may be able to push through its overburden, this is known as forceful diapirism. Many salt diapirs may contain elements of both active and passive salt movement. An active salt structure may pierce its overburden and from then on continue to develop as a purely passive salt diapir. | 0 | Salts |
Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts. | 1 | Semiconductor Materials |
As a significant product of copper mining, copper(II) oxide is the starting point for the production of other copper salts. For example, many wood preservatives are produced from copper oxide.
Cupric oxide is used as a pigment in ceramics to produce blue, red, and green, and sometimes gray, pink, or black glazes.
It is incorrectly used as a dietary supplement in animal feed. Due to low bioactivity, negligible copper is absorbed.
It is used when welding with copper alloys.
A copper oxide electrode formed part of the early battery type known as the Edison–Lalande cell. Copper oxide was also used in a lithium battery type (IEC 60086 code "G"). | 1 | Semiconductor Materials |
Iron phosphide is a chemical compound of iron and phosphorus, with a formula of FeP. Its physical appearance is grey, hexagonal needles.
Manufacturing of iron phosphide takes place at elevated temperatures, where the elements combine directly. Iron phosphide reacts with moisture and acids producing phosphine (PH), a toxic and pyrophoric gas.
Iron phosphide can be used as a semiconductor. It has use in high power, high frequency applications, such as laser diodes.
Below a Néel temperature of about 119 K, FeP takes on an helimagnetic structure. | 1 | Semiconductor Materials |
The Bonneville Salt Flats in Utah, where many land speed records have been set, are a well-known salt pan in the arid regions of the western United States.
The Etosha pan, in the Etosha National Park in Namibia, is another prominent example of a salt pan.
The Salar de Uyuni in Bolivia is the largest salt pan in the world. It contains 50% to 70% of the world's known lithium reserves. The large area, clear skies, and exceptional flatness of the surface make the Salar an ideal object for calibrating the altimeters of Earth observation satellites.
Parts of Rann of Kutch (India) are salt marsh in the wet season and salt pan in the dry season. | 0 | Salts |
Magnetite has been found as nano-crystals in magnetotactic bacteria (42–45 nm) and in the beak tissue of homing pigeons. | 1 | Semiconductor Materials |
The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrites metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fools gold. The color has also led to the nicknames brass, brazzle, and brazil, primarily used to refer to pyrite found in coal.
The name pyrite is derived from the Greek (), stone or mineral which strikes fire, in turn from (), fire. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite.
By Georgius Agricola's time, , the term had become a generic term for all of the sulfide minerals.
Pyrite is usually found associated with other sulfides or oxides in quartz veins, sedimentary rock, and metamorphic rock, as well as in coal beds and as a replacement mineral in fossils, but has also been identified in the sclerites of scaly-foot gastropods. Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "invisible gold" incorporated into the pyrite (see Carlin-type gold deposit). It has been suggested that the presence of both gold and arsenic is a case of coupled substitution but as of 1997 the chemical state of the gold remained controversial. | 1 | Semiconductor Materials |
In chemistry, a selenosulfide refers to distinct classes of inorganic and organic compounds containing sulfur and selenium. The organic derivatives contain Se-S bonds, whereas the inorganic derivatives are more variable. | 1 | Semiconductor Materials |
An acid with higher Acid dissociation constant| value dominates the chemical reaction. It serves as a better contributor of protons (). A comparison between the and Base dissociation constant| indicates the acid–base property of the resulting solution by which:
# The solution is acidic if . It contains a greater concentration of ions than concentration of ions due more extensive of cation hydrolysis compared to that of anion hydrolysis.
# The solution is alkali if . Anions hydrolyze more than cations, causing an exceeding concentration of ions.
# The solution is expected to be neutral only when .
Other possible factors that could vary pH level of a solution are the relevant equilibrium constants and the additional amounts of any base or acid.
For example, in ammonium chloride solution, is the main influence for acidic solution. It has greater value compared to that of water molecules; of is , and of is . This ensures its deprotonation when reacting with water, and is responsible for the pH below 7 at room temperature. will have no affinity for nor tendency to hydrolyze, as its value is very low ( of is ).
Hydrolysis of ammonium at room temperature produces: | 0 | Salts |
SnO coatings can be applied using chemical vapor deposition, vapour deposition techniques that employ SnCl or organotin trihalides e.g. butyltin trichloride as the volatile agent. This technique is used to coat glass bottles with a thin (, which helps to adhere a subsequent, protective polymer coating such as polyethylene to the glass.
Thicker layers doped with Sb or F ions are electrically conducting and used in electroluminescent devices and photovoltaics. | 1 | Semiconductor Materials |
Counterion condensation is a phenomenon described by Manning's
theory (Manning 1969), which assumes that counterions can condense
onto polyions until the charged density between neighboring monomer charges
along the polyion chain is reduced below a certain critical value. In the model the
real polyion chain is replaced by an idealized line charge, where the polyion
is represented by a uniformly charged thread of zero radius, infinite
length and finite charge density, and the condensed counterion layer is
assumed to be in physical equilibrium with the ionic atmosphere surrounding
the polyion. The uncondensed mobile ions in the ionic atmosphere are treated
within the Debye–Hückel (DH) approximation. The
phenomenon of counterion condensation now takes place when the dimensionless
Coulomb coupling strength
where represents the Bjerrum length and
the distance between neighboring charged monomers.
In this case the Coulomb interactions dominate over
the thermal interactions and counterion condensation is favored. For many standard
polyelectrolytes, this phenomenon is relevant, since the
distance between neighboring monomer charges typically ranges between 2 and 3 Å and
7 Å in water.
The Manning theory states that the fraction of "condensed" counter ions is , where "condensed" means that the counter ions are located within the Manning radius .
At infinite dilution the Manning radius diverges and the actual concentration of ions close to the charged rod is reduced (in agreement with the law of dilution). | 0 | Salts |
Estropipate is used to:
* Alleviate symptoms of menopause as menopausal hormone therapy
* Treat some types of infertility
* Treat some conditions leading to underdevelopment of female sexual characteristics
* Treat vaginal atrophy
* Treat some types of breast cancer (particularly in men and postmenopausal women)
* Treat prostate cancer
* Prevent osteoporosis | 0 | Salts |
By nonlinear optical spectroscopy using ultrafast laser pulses with durations on the order of ten to hundreds of femtoseconds, several coherent effects have been observed and interpreted.
Such studies and their proper theoretical analysis have revealed a wealth of information on the nature of the photoexcited quantum states, the coupling among them, and their dynamical evolution on ultrashort time scales. In the following, a few important effects are briefly described. | 1 | Semiconductor Materials |
Caliche forms where annual precipitation is less than per year and the mean annual temperature exceeds . Higher rainfall leaches excess calcium completely from the soil, while in very arid climates, rainfall is inadequate to leach calcium at all and only thin surface layers of calcite are formed. Plant roots play an important role in caliche formation, by releasing large amounts of carbon dioxide into the A horizon of the soil. Carbon dioxide levels here can exceed 15 times normal atmospheric values. This allows calcium carbonate to dissolve as bicarbonate. Where rainfall is adequate but not excessive, the calcium bicarbonate is carried down into the B horizon. Here there is less biological activity, the carbon dioxide level is much lower, and the bicarbonate reverts to insoluble carbonate. A mixture of calcium carbonate and clay particles accumulates, first forming grains, then small clumps, then a discernible layer, and finally, a thicker, solid bed.
However, caliche also forms in other ways. It can form when water rises through capillary action. In an arid region, rainwater sinks into the ground very quickly. Later, as the surface dries out, the water below the surface rises, carrying up dissolved minerals from lower layers. These precipitate as water evaporates and carbon dioxide is lost. This water movement forms a caliche that is close to the surface. Caliche can also form on outcrops of porous rocks or in rock fissures where water is trapped and evaporates. In general, caliche deposition is a slow process, requiring several thousand years.
The depth of the caliche layer is sensitive to mean annual rainfall. When rainfall is around per year, the caliche layer will be as shallow as . When rainfall is around per year, the caliche layer will be at a depth of around . The caliche layer disappears complete in temperate climates if annual rainfall exceeds .
The source of the calcium in caliche may be the underlying bedrock, but caliche can form even over bedrock that is not rich in calcium. This is attributed to calcium brought in as aeolian dust. | 0 | Salts |
Caesium auride is the inorganic compound with the formula CsAu. It is the Cs salt of the unusual Au anion.
__TOC__ | 1 | Semiconductor Materials |
Samarium(III) arsenide is a binary inorganic compound of samarium and arsenic with the chemical formula SmAs. | 1 | Semiconductor Materials |
The Jackson–Meisenheimer complex was named after the American organic chemist, Charles Loring Jackson (1847–1935) and the German organic chemist, Jakob Meisenheimer (1876–1934).
The Janovski reaction was named for the Czech chemist, Jaroslav Janovski (1850–1907).
The Zimmermann reaction was named after the German chemist, Wilhelm Zimmermann (1910–1982).
Lastly, the Wheland intermediate was named after the American chemist, George Willard Wheland (1907–1976) | 0 | Salts |
The carbides of the group 4, 5 and 6 transition metals (with the exception of chromium) are often described as interstitial compounds. These carbides have metallic properties and are refractory. Some exhibit a range of stoichiometries, being a non-stoichiometric mixture of various carbides arising due to crystal defects. Some of them, including titanium carbide and tungsten carbide, are important industrially and are used to coat metals in cutting tools.
The long-held view is that the carbon atoms fit into octahedral interstices in a close-packed metal lattice when the metal atom radius is greater than approximately 135 pm:
*When the metal atoms are cubic close-packed, (ccp), then filling all of the octahedral interstices with carbon achieves 1:1 stoichiometry with the rock salt structure.
*When the metal atoms are hexagonal close-packed, (hcp), as the octahedral interstices lie directly opposite each other on either side of the layer of metal atoms, filling only one of these with carbon achieves 2:1 stoichiometry with the CdI structure.
The following table shows structures of the metals and their carbides. (N.B. the body centered cubic structure adopted by vanadium, niobium, tantalum, chromium, molybdenum and tungsten is not a close-packed lattice.) The notation "h/2" refers to the MC type structure described above, which is only an approximate description of the actual structures. The simple view that the lattice of the pure metal "absorbs" carbon atoms can be seen to be untrue as the packing of the metal atom lattice in the carbides is different from the packing in the pure metal, although it is technically correct that the carbon atoms fit into the octahedral interstices of a close-packed metal lattice.
For a long time the non-stoichiometric phases were believed to be disordered with a random filling of the interstices, however short and longer range ordering has been detected.
Iron forms a number of carbides, , and . The best known is cementite, FeC, which is present in steels. These carbides are more reactive than the interstitial carbides; for example, the carbides of Cr, Mn, Fe, Co and Ni are all hydrolysed by dilute acids and sometimes by water, to give a mixture of hydrogen and hydrocarbons. These compounds share features with both the inert interstitials and the more reactive salt-like carbides.
Some metals, such as lead and tin, are believed not to form carbides under any circumstances. There exists however a mixed titanium-tin carbide, which is a two-dimensional conductor. | 0 | Salts |
Uranium dioxide is carbonized in contact with carbon, forming uranium carbide and carbon monoxide.
This process must be done under an inert gas as uranium carbide is easily oxidized back into uranium oxide. | 1 | Semiconductor Materials |
Copper(II) chloride, also known as cupric chloride, is an inorganic compound with the chemical formula . The monoclinic yellowish-brown anhydrous form slowly absorbs moisture to form the orthorhombic blue-green dihydrate , with two water molecules of hydration. It is industrially produced for use as a co-catalyst in the Wacker process.
Both the anhydrous and the dihydrate forms occur naturally as the rare minerals tolbachite and eriochalcite, respectively. | 1 | Semiconductor Materials |
Tungsten disilicide (WSi) is an inorganic compound, a silicide of tungsten. It is an electrically conductive ceramic material. | 1 | Semiconductor Materials |
Within any crystal, there will usually be some defects. To maintain electroneutrality of the crystals, defects that involve loss of a cation will be associated with loss of an anion, i.e. these defects come in pairs. Frenkel defects consist of a cation vacancy paired with a cation interstitial and can be generated anywhere in the bulk of the crystal, occurring most commonly in compounds with a low coordination number and cations that are much smaller than the anions. Schottky defects consist of one vacancy of each type, and are generated at the surfaces of a crystal, occurring most commonly in compounds with a high coordination number and when the anions and cations are of similar size. If the cations have multiple possible oxidation states, then it is possible for cation vacancies to compensate for electron deficiencies on cation sites with higher oxidation numbers, resulting in a non-stoichiometric compound. Another non-stoichiometric possibility is the formation of an F-center, a free electron occupying an anion vacancy. When the compound has three or more ionic components, even more defect types are possible. All of these point defects can be generated via thermal vibrations and have an equilibrium concentration. Because they are energetically costly but entropically beneficial, they occur in greater concentration at higher temperatures. Once generated, these pairs of defects can diffuse mostly independently of one another, by hopping between lattice sites. This defect mobility is the source of most transport phenomena within an ionic crystal, including diffusion and solid state ionic conductivity. When vacancies collide with interstitials (Frenkel), they can recombine and annihilate one another. Similarly, vacancies are removed when they reach the surface of the crystal (Schottky). Defects in the crystal structure generally expand the lattice parameters, reducing the overall density of the crystal. Defects also result in ions in distinctly different local environments, which causes them to experience a different crystal-field symmetry, especially in the case of different cations exchanging lattice sites. This results in a different splitting of d-electron orbitals, so that the optical absorption (and hence colour) can change with defect concentration. | 0 | Salts |
PtSi is a semiconductor and a Schottky barrier with high stability and good sensitivity, and can be used in infrared detection, thermal imaging, or ohmic and Schottky contacts. Platinum silicide was most widely studied and used in the 1980s and 90s, but has become less commonly used, due to its low quantum efficiency. PtSi is now most commonly used in infrared detectors, due to the large size of wavelengths it can be used to detect. It has also been used in detectors for infrared astronomy. It can operate with good stability up to 0.05 °C. Platinum silicide offers high uniformity of arrays imaged. The low cost and stability makes it suited for preventative maintenance and scientific infrared imaging. | 1 | Semiconductor Materials |
Sodium perxenate, NaXeO, can be used for the analytic separation of trace amounts of americium from curium. The separation involves the oxidation of Am to Am by sodium perxenate in acidic solution in the presence of La, followed by treatment with calcium fluoride, which forms insoluble fluorides with Cm and La, but retains Am and Pu in solution as soluble fluorides. | 0 | Salts |
Hard toilet soap with a pleasant smell was produced in the Middle East during the Islamic Golden Age, when soap-making became an established industry. Recipes for soap-making are described by Muhammad ibn Zakariya al-Razi (c. 865–925), who also gave a recipe for producing glycerine from olive oil. In the Middle East, soap was produced from the interaction of fatty oils and fats with alkali. In Syria, soap was produced using olive oil together with alkali and lime. Soap was exported from Syria to other parts of the Muslim world and to Europe.
A 12th-century document describes the process of soap production. It mentions the key ingredient, alkali, which later became crucial to modern chemistry, derived from al-qaly or "ashes".
By the 13th century, the manufacture of soap in the Middle East had become a major cottage industry, with sources in Nablus, Fes, Damascus, and Aleppo. | 0 | Salts |
The few examples given above represent only a small subset of several further phenomena which demonstrate that the coherent optical response of semiconductors and semiconductor nanostructures is strongly influenced by many-body effects.
Other interesting research directions which similarly require an adequate theoretical analysis including many-body interactions are, e.g., phototransport phenomena where optical fields generate and/or probe electronic currents, the combined spectroscopy with optical and terahertz fields, see article terahertz spectroscopy and technology, and the rapidly developing area of semiconductor quantum optics, see article semiconductor quantum optics with dots. | 1 | Semiconductor Materials |
Perxenic acid is the unstable conjugate acid of the perxenate anion, formed by the solution of xenon tetroxide in water. It has not been isolated as a free acid, because under acidic conditions it rapidly decomposes into xenon trioxide and oxygen gas:
Its extrapolated formula, HXeO, is inferred from the octahedral geometry of the perxenate ion () in its alkali metal salts.
The pK of aqueous perxenic acid has been indirectly calculated to be below 0, making it an extremely strong acid. Its first ionization yields the anion , which has a pK value of 4.29, still relatively acidic. The twice deprotonated species has a pK value of 10.81. Due to its rapid decomposition under acidic conditions as described above, however, it is most commonly known as perxenate salts, bearing the anion . | 0 | Salts |
Solubility of salts in organic solvents is a function of both the cation and the anion. The solubility of cations in organic solvents can be enhanced when the anion is lipophilic. Similarly, the solubility of anions in organic solvents is enhanced with lipophilic cations. The most common lipophilic cations are quaternary ammonium cations, called "quat salts".
Many cationic organometallic complexes are isolated with inert, noncoordinating counterions. Ferrocenium tetrafluoroborate is one such example. | 0 | Salts |
CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure. Upon heating it transforms to the zincblende form and the transition temperature decreases from 1045 °C for x = 0 to 805 °C for x = 1. | 1 | Semiconductor Materials |
Beginning in the 14th century potash was mined in Ethiopia. One of the world's largest deposits, 140 to 150 million tons, is located in the Dallol area of the Afar Region. | 0 | Salts |
Bittern has been extracted for a long time, at least several centuries. The Dutch chemist Petrus Jacobus Kipp (1808–1864) experimented with saturated solutions of bittern. The term for the solution is a modification of "bitter". | 0 | Salts |
The desalination process consists of the separation of salts from an aqueous solution to obtain fresh water from a source of seawater or brackish water; and in turn, a discharge is generated, commonly called brine. | 0 | Salts |
A Meisenheimer complex or Jackson–Meisenheimer complex in organic chemistry is a 1:1 reaction adduct between an arene carrying electron withdrawing groups and a nucleophile. These complexes are found as reactive intermediates in nucleophilic aromatic substitution but stable and isolated Meisenheimer salts are also known. | 0 | Salts |
Used as moderate blue coloring agent in blue flame compositions with additional chlorine donors and oxidizers such as chlorates and perchlorates. Providing oxygen it can be used as flash powder oxidizer with metal fuels such as magnesium, aluminium, or magnalium powder. Sometimes it is used in strobe effects and thermite compositions as crackling stars effect. | 1 | Semiconductor Materials |
Living coral reefs are endangered and cannot be harvested without significant damage to the ecosystem, and because of this, coral calcium is harvested by grinding up above-ground limestone deposits that were once part of a coral reef. Calcium from coral sources needs to be refined to remove pollutants of the source environment. It is marketed as a dietary supplement, but its benefits over other calcium supplements are unproven and biologically unlikely, and several marketers have been found guilty of fraud and were ordered to pay $20.4 million and to refrain from making unsubstantiated claims in the future. Additionally, coral near Okinawa has absorbed relatively high amounts of lead and mercury, leading to concern that these unregulated supplements may be contaminated. Further, coral takes millennia to grow, leading to environmental concerns if harvesting of live coral becomes widespread. | 0 | Salts |
Europium(II) oxide can be prepared by the reduction of europium(III) oxide with elemental europium at 800 °C and subsequent vacuum distillation at 1150 °C.
:EuO + Eu → 3 EuO
It is also possible to synthesize from the reaction of europium oxychloride and lithium hydride.
:2 EuOCl + 2 LiH → 2 EuO + 2 LiCl + H
In modern research, thin films can be manufactured by molecular beam epitaxy directly from europium atoms and oxygen molecules. These films have contamination of Eu of less than 1%. | 1 | Semiconductor Materials |
Measurement and definition difficulties arise because natural waters contain a complex mixture of many different elements from different sources (not all from dissolved salts) in different molecular forms. The chemical properties of some of these forms depend on temperature and pressure. Many of these forms are difficult to measure with high accuracy, and in any case complete chemical analysis is not practical when analyzing multiple samples. Different practical definitions of salinity result from different attempts to account for these problems, to different levels of precision, while still remaining reasonably easy to use.
For practical reasons salinity is usually related to the sum of masses of a subset of these dissolved chemical constituents (so-called solution salinity), rather than to the unknown mass of salts that gave rise to this composition (an exception is when artificial seawater is created). For many purposes this sum can be limited to a set of eight major ions in natural waters, although for seawater at highest precision an additional seven minor ions are also included. The major ions dominate the inorganic composition of most (but by no means all) natural waters. Exceptions include some pit lakes and waters from some hydrothermal springs.
The concentrations of dissolved gases like oxygen and nitrogen are not usually included in descriptions of salinity. However, carbon dioxide gas, which when dissolved is partially converted into carbonates and bicarbonates, is often included. Silicon in the form of silicic acid, which usually appears as a neutral molecule in the pH range of most natural waters, may also be included for some purposes (e.g., when salinity/density relationships are being investigated). | 0 | Salts |
Eye drops are saline-containing drops used on the eye. Depending on the condition being treated, they may contain steroids, antihistamines, sympathomimetics, beta receptor blockers, parasympathomimetics, parasympatholytics, prostaglandins, non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics or topical anesthetics. Eye drops sometimes do not have medications in them and are only lubricating and tear-replacing solutions. | 0 | Salts |
Addition of a complexant like crown ether or [[2.2.2-Cryptand|[2.2.2-cryptand]] to a solution of [Na(NH)]e affords [Na (crown ether)]e or [Na(2,2,2-crypt)]e. Evaporation of these solutions yields a blue-black paramagnetic solid with the formula [Na(2,2,2-crypt)]e.
Most solid electride salts decompose above 240 K, although [CaAlO](e) is stable at room temperature. In these salts, the electron is delocalized between the cations. Electrides are paramagnetic, and are Mott insulators. Properties of these salts have been analyzed.
ThI and ThI have also been reported to be electride compounds. Similarly, Cerium#Chemistry|, , , and are all electride salts with a tricationic metal ion. | 0 | Salts |
Acidic salts are often used in foods as part of leavening agents. In this context, the acid salts are referred to as "leavening acids." Common leavening acids include cream of tartar and monocalcium phosphate.
An acidic salt can be mixed with an alkali salt (such as sodium bicarbonate or baking soda) to create baking powders which release carbon dioxide. Leavening agents can be slow-acting (e.g. sodium aluminum phosphate) which react when heated, or fast-acting (e.g., cream of tartar) which react immediately at low temperatures. Double-acting baking powders contain both slow- and fast-acting leavening agents and react at low and high temperatures to provide leavening rising throughout the baking process.
Disodium phosphate, , is used in foods and monosodium phosphate, , is used in animal feed, toothpaste and evaporated milk. | 0 | Salts |
Examples of halide compounds are:
* Sodium chloride (NaCl)
* Potassium chloride (KCl)
* Potassium iodide (KI)
* Lithium chloride (LiCl)
* Copper(II) chloride ()
* Silver chloride (AgCl)
* Calcium chloride ()
* Chlorine fluoride (ClF)
* Organohalides
** Bromomethane ()
** Iodoform ()
* Hydrogen chloride (HCl)
*Hydrogen bromide (HBr) | 0 | Salts |
UO is used mainly as nuclear fuel, specifically as UO or as a mixture of UO and PuO (plutonium dioxide) called a mixed oxide (MOX fuel), in the form of fuel rods in nuclear reactors.
The thermal conductivity of uranium dioxide is very low when compared with uranium, uranium nitride, uranium carbide and zirconium cladding material. This low thermal conductivity can result in localised overheating in the centres of fuel pellets. The graph below shows the different temperature gradients in different fuel compounds. For these fuels, the thermal power density is the same and the diameter of all the pellets are the same. | 1 | Semiconductor Materials |
Researchers have fabricated transistors of phosphorene to examine its performance in actual devices. Phosphorene-based transistor consists of a channel of 1.0 μm and uses few layered phosphorene with a thickness varying from 2.1 to over 20 nm. Reduction of the total resistance with decreasing gate voltage is observed, indicating the p-type characteristic of phosphorene. Linear I-V relationship of transistor at low drain bias suggests good contact properties at the phosphorene/metal interface. Good current saturation at high drain bias values was observed. However, it was seen that the mobility is reduced in few-layer phosphorene when compared to bulk black phosphorus. Field-effect mobility of phosphorene-based transistor shows a strong thickness dependence, peaking at around 5 nm and decrease steadily with further increase of crystal thickness.
Atomic layer deposition (ALD) dielectric layer and/or hydrophobic polymer is used as encapsulation layers in order to prevent device degradation and failure. Phosphorene devices are reported to maintain their function for weeks with encapsulation layer, whereas experience device failure within a week when exposed to ambient condition. | 1 | Semiconductor Materials |
Other methods include dissolution mining and evaporation methods from brines. In the evaporation method, hot water is injected into the potash, which is dissolved and then pumped to the surface where it is concentrated by solar induced evaporation. Amine reagents are then added to either the mined or evaporated solutions. The amine coats the KCl but not NaCl. Air bubbles cling to the amine + KCl and float it to the surface while the NaCl and clay sink to the bottom. The surface is skimmed for the amine + KCl, which is then dried and packaged for use as a K rich fertilizer—KCl dissolves readily in water and is available quickly for plant nutrition.
Recovery of potassium fertilizer salts from sea water has been studied in India. During extraction of salt from seawater by evaporation, potassium salts get concentrated in bittern, an effluent from the salt industry. | 0 | Salts |
Soaps are key components of most lubricating greases and thickeners. Greases are usually emulsions of calcium soap or lithium soap and mineral oil. Many other metallic soaps are also useful, including those of aluminium, sodium, and mixtures thereof. Such soaps are also used as thickeners to increase the viscosity of oils. In ancient times, lubricating greases were made by the addition of lime to olive oil.
Metal soaps are also included in modern artists' oil paints formulations as a rheology modifier. | 0 | Salts |
Potash was one of the most important industrial chemicals. It was refined from the ashes of broadleaved trees and produced primarily in the forested areas of Europe, Russia, and North America. Although methods for producing artificial alkalis were invented in the late 18th century, these did not become economical until the late 19th century and so the dependence on organic sources of potash remained.
Potash became an important international trade commodity in Europe from at least the early 14th century. It is estimated that European imports of potash required 6 or more million cubic metres each year from the early 17th century. Between 1420 and 1620, the primary exporting cities for wood-derived potash were Gdańsk, Königsberg and Riga. In the late 15th century, London was the lead importer due to its position as the centre of soft soap making while the Dutch dominated as suppliers and consumers in the 16th century. From the 1640s, geopolitical disruptions (i.e. Russo-Polish War (1654–1667)) meant that the centres of export moved from the Baltic to Archangel, Russia. In 1700, Russian ash was dominant though Gdańsk remained notable for the quality of its potash. | 0 | Salts |
Their tendency to form host–guest complexes is key to the molecular machines recognized by the 2016 Nobel Prize in Chemistry.
Viologens are used in the negative electrolytes of some experimental flow batteries. Viologens have been modified to optimize their performance in such batteries, e.g. by incorporating them into redox-active polymers.
Viologen catalysts have been reported to have the potential to oxidize glucose and other carbohydrates catalytically in a mildly alkaline solution, which makes direct carbohydrate fuel cells possible. | 0 | Salts |
On the Orkney islands, kelp ash provided potash and soda ash, production starting "possibly as early as 1719" and lasting for a century. The products were "eagerly sought after by the glass and soap industries of the time." | 0 | Salts |
Polyvinylcarbazole is soluble in aromatic hydrocarbons, halogenated hydrocarbons and ketones. It is resistant to acids, alkalis, polar solvents and aliphatic hydrocarbons. The addition of PVK to other plastic masses increases their temperature resistance. | 1 | Semiconductor Materials |
The interaction of matter with light, i.e., electromagnetic fields, is able to generate a coherent superposition of excited quantum states in the material. Coherent denotes the fact that the material excitations have a well defined phase relation which originates from the phase of the incident electromagnetic wave. Macroscopically, the superposition state of the material results in an optical polarization, i.e., a rapidly oscillating dipole density. The optical polarization is a genuine non-equilibrium quantity that decays to zero when the excited system relaxes to its equilibrium state after the electromagnetic pulse is switched off. Due to this decay which is called dephasing, coherent effects are observable only for a certain temporal duration after pulsed photoexcitation. Various materials such as atoms, molecules, metals, insulators, semiconductors are studied using coherent optical spectroscopy and such experiments and their theoretical analysis has revealed a wealth of insights on the involved matter states and their dynamical evolution.
This article focusses on coherent optical effects in semiconductors and semiconductor nanostructures. After an introduction into the basic principles, the semiconductor Bloch equations (abbreviated as SBEs) which are able to theoretically describe coherent semiconductor optics on the basis of a fully microscopic many-body quantum theory are introduced. Then, a few prominent examples for coherent effects in semiconductor optics are described all of which can be understood theoretically on the basis of the SBEs. | 1 | Semiconductor Materials |
The carbides of silicon and boron are described as "covalent carbides", although virtually all compounds of carbon exhibit some covalent character. Silicon carbide has two similar crystalline forms, which are both related to the diamond structure. Boron carbide, BC, on the other hand, has an unusual structure which includes icosahedral boron units linked by carbon atoms. In this respect boron carbide is similar to the boron rich borides. Both silicon carbide (also known as carborundum) and boron carbide are very hard materials and refractory. Both materials are important industrially. Boron also forms other covalent carbides, such as BC. | 0 | Salts |
A metallic soap is a metallic salt of a fatty acid. Theoretically, soaps can be made of any metal, although not all enjoy practical uses. Varying the metal can strongly affect the properties of the compound, particularly its solubility. | 0 | Salts |
Brines are produced in multiple ways in nature. Modification of seawater via evaporation results in the concentration of salts in the residual fluid, a characteristic geologic deposit called an evaporite is formed as different dissolved ions reach the saturation states of minerals, typically gypsum and halite. Dissolution of such salt deposits into water can produce brines as well. As seawater freezes, dissolved ions tend to remain in solution resulting in a fluid termed a cryogenic brine. At the time of formation, these cryogenic brines are by definition cooler than the freezing temperature of seawater and can produce a feature called a brinicle where cool brines descend, freezing the surrounding seawater.
The brine cropping out at the surface as saltwater springs are known as "licks" or "salines". The contents of dissolved solids in groundwater vary highly from one location to another on Earth, both in terms of specific constituents (e.g. halite, anhydrite, carbonates, gypsum, fluoride-salts, organic halides, and sulfate-salts) and regarding the concentration level. Using one of several classification of groundwater based on total dissolved solids (TDS), brine is water containing more than 100,000 mg/L TDS. Brine is commonly produced during well completion operations, particularly after the hydraulic fracturing of a well. | 0 | Salts |
Saline lakes are declining worldwide on every continent except Antarctica, mainly due to human causes, such as damming, diversions, and withdrawals. One of the largest factors causing this decline is agricultural irrigation. Among the most commonly cited examples is the Aral Sea, which has shrunk 90% in volume and 74% in area, which is mainly because of irrigation.
Another anthropogenic threat is climate change. Human-caused climate change is increasing temperature in many arid regions, drying soil, increasing evaporation, and reducing inflows to saline lakes.
Decline of saline lakes leads to many environmental problems, including human problems, such as toxic dust storms and air pollution, disrupted local water cycles, economic losses, loss of ecosystems, and more. It can even be more costly. For example, in the case of the decline of Owens Lake, dust stirred up from the dry lakebed has led to air quality higher than allowed by US-air quality standards. This has resulted in the city of Los Angeles spending $3.6 billion over the next 25 years to mitigate dust from the desiccated lakebed, which is more than the value of the diverted water.
Solutions to the decline of saline lakes can be multifaceted, and include water conservation and water budgeting, and mitigating climate change. | 0 | Salts |
According to the nomenclature recommended by IUPAC, ionic compounds are named according to their composition, not their structure. In the most simple case of a binary ionic compound with no possible ambiguity about the charges and thus the stoichiometry, the common name is written using two words. The name of the cation (the unmodified element name for monatomic cations) comes first, followed by the name of the anion. For example, MgCl is named magnesium chloride, and NaSO is named sodium sulfate (, sulfate, is an example of a polyatomic ion). To obtain the empirical formula from these names, the stoichiometry can be deduced from the charges on the ions, and the requirement of overall charge neutrality.
If there are multiple different cations and/or anions, multiplicative prefixes (di-, tri-, tetra-, ...) are often required to indicate the relative compositions, and cations then anions are listed in alphabetical order. For example, KMgCl is named magnesium potassium trichloride to distinguish it from KMgCl, magnesium dipotassium tetrachloride (note that in both the empirical formula and the written name, the cations appear in alphabetical order, but the order varies between them because the symbol for potassium is K). When one of the ions already has a multiplicative prefix within its name, the alternate multiplicative prefixes (bis-, tris-, tetrakis-, ...) are used. For example, Ba(BrF) is named barium bis(tetrafluoridobromate).
Compounds containing one or more elements which can exist in a variety of charge/oxidation states will have a stoichiometry that depends on which oxidation states are present, to ensure overall neutrality. This can be indicated in the name by specifying either the oxidation state of the elements present, or the charge on the ions. Because of the risk of ambiguity in allocating oxidation states, IUPAC prefers direct indication of the ionic charge numbers. These are written as an arabic integer followed by the sign (... , 2−, 1−, 1+, 2+, ...) in parentheses directly after the name of the cation (without a space separating them). For example, FeSO is named iron(2+) sulfate (with the 2+ charge on the Fe ions balancing the 2− charge on the sulfate ion), whereas Fe(SO) is named iron(3+) sulfate (because the two iron ions in each formula unit each have a charge of 3+, to balance the 2− on each of the three sulfate ions). Stock nomenclature, still in common use, writes the oxidation number in Roman numerals (... , −II, −I, 0, I, II, ...). So the examples given above would be named iron(II) sulfate and iron(III) sulfate respectively. For simple ions the ionic charge and the oxidation number are identical, but for polyatomic ions they often differ. For example, the uranyl(2+) ion, , has uranium in an oxidation state of +6, so would be called a dioxouranium(VI) ion in Stock nomenclature. An even older naming system for metal cations, also still widely used, appended the suffixes -ous and -ic to the Latin root of the name, to give special names for the low and high oxidation states. For example, this scheme uses "ferrous" and "ferric", for iron(II) and iron(III) respectively, so the examples given above were classically named ferrous sulfate and ferric sulfate.
Common salt-forming cations include:
* Ammonium
* Calcium
* Iron and
* Magnesium
* Potassium
* Pyridinium
* Quaternary ammonium , R being an alkyl group or an aryl group
* Sodium
* Copper
Common salt-forming anions (parent acids in parentheses where available) include:
* Acetate (acetic acid)
* Carbonate (carbonic acid)
* Chloride (hydrochloric acid)
* Citrate (citric acid)
* Cyanide (hydrocyanic acid)
* Fluoride (hydrofluoric acid)
* Nitrate (nitric acid)
* Nitrite (nitrous acid)
* Oxide (water)
* Phosphate (phosphoric acid)
* Sulfate (sulfuric acid)
Salts with varying number of hydrogen atoms replaced by cations as compared to their parent acid can be referred to as monobasic, dibasic, or tribasic, identifying that one, two, or three hydrogen atoms have been replaced; polybasic salts refer to those with more than one hydrogen atom replaced. Examples include:
* Sodium phosphate monobasic (NaHPO)
* Sodium phosphate dibasic (NaHPO)
* Sodium phosphate tribasic (NaPO) | 0 | Salts |
NaH is colorless, although samples generally appear grey. NaH is around 40% denser than Na (0.968 g/cm).
NaH, like LiH, KH, RbH, and CsH, adopts the NaCl crystal structure. In this motif, each Na ion is surrounded by six H centers in an octahedral geometry. The ionic radii of H (146 pm in NaH) and F (133 pm) are comparable, as judged by the Na−H and Na−F distances. | 1 | Semiconductor Materials |
Natural salt pans or salt flats are flat expanses of ground covered with salt and other minerals, usually shining white under the sun. They are found in deserts and are natural formations (unlike salt evaporation ponds, which are artificial).
A salt pan forms by evaporation of a water pool, such as a lake or pond. This happens in climates where the rate of water evaporation exceeds the rate of that is, in a desert. If the water cannot drain into the ground, it remains on the surface until it evaporates, leaving behind minerals precipitated from the salt ions dissolved in the water. Over thousands of years, the minerals (usually salts) accumulate on the surface. These minerals reflect the sun's rays (through radiation) and often appear as white areas.
Salt pans can be dangerous. The crust of salt can conceal a quagmire of mud that can engulf a truck. The Qattara Depression in the eastern Sahara Desert contains many such traps which served as strategic barriers during World War II. | 0 | Salts |
Common material characterization techniques such as electron microscopy can damage samples of lead (II) iodide. Thin films of lead (II) iodide are unstable in ambient air. Ambient air oxygen oxidizes iodide into elemental iodine: | 1 | Semiconductor Materials |
Copper(I) iodide, like most binary (containing only two elements) metal halides, is an inorganic polymer. It has a rich phase diagram, meaning that it exists in several crystalline forms. It adopts a zinc blende structure below 390 °C (γ-CuI), a wurtzite structure between 390 and 440 °C (β-CuI), and a rock salt structure above 440 °C (α-CuI). The ions are tetrahedrally coordinated when in the zinc blende or the wurtzite structure, with a Cu-I distance of 2.338 Å. Copper(I) bromide and copper(I) chloride also transform from the zinc blende structure to the wurtzite structure at 405 and 435 °C, respectively. Therefore, the longer the copper–halide bond length, the lower the temperature needs to be to change the structure from the zinc blende structure to the wurtzite structure. The interatomic distances in copper(I) bromide and copper(I) chloride are 2.173 and 2.051 Å, respectively. Consistent with its covalency, CuI is a p-type semiconductor. | 1 | Semiconductor Materials |
It is used in microelectronics as a contact material, with resistivity 60–80 μΩ cm; it forms at 1000 °C. It is often used as a shunt over polysilicon lines to increase their conductivity and increase signal speed. Tungsten disilicide layers can be prepared by chemical vapor deposition, e.g. using monosilane or dichlorosilane with tungsten hexafluoride as source gases. The deposited film is non-stoichiometric, and requires annealing to convert to more conductive stoichiometric form. Tungsten disilicide is a replacement for earlier tungsten films. Tungsten disilicide is also used as a barrier layer between silicon and other metals, e.g. tungsten.
Tungsten disilicide is also of value towards use in microelectromechanical systems, where it is mostly applied as thin films for fabrication of microscale circuits. For such purposes, films of tungsten disilicide can be plasma-etched using e.g. nitrogen trifluoride gas.
WSi performs well in applications as oxidation-resistant coatings. In particular, in similarity to Molybdenum disilicide, MoSi, the high emissivity of tungsten disilicide makes this material attractive for high temperature radiative cooling, with implications in heat shields. | 1 | Semiconductor Materials |
When one or more salt layers are present during extensional tectonics, a characteristic set of structures is formed. Extensional faults propagate up from the middle part of the crust until they encounter the salt layer. The weakness of the salt prevents the fault from propagating through. However, continuing displacement on the fault offsets the base of the salt and causes bending of the overburden layer. Eventually the stresses caused by this bending will be sufficient to fault the overburden. The types of structures developed depend on the initial salt thickness. In the case of a very thick salt layer there is no direct spatial relationship between the faulting beneath the salt and that in the overburden, such a system is said to be unlinked. For intermediate salt thicknesses, the overburden faults are spatially related to the deeper faults, but offset from them, normally into the footwall; these are known as soft-linked systems. When the salt layer becomes thin enough, the fault that develops in the overburden is closely aligned with that beneath the salt, and forms a continuous fault surface after only a relatively small displacement, forming a hard-linked fault.
In areas of thrust tectonics salt layers act as preferred detachment planes. In the Zagros fold and thrust belt, variations in the thickness and therefore effectiveness of the late Neoproterozoic to Early Cambrian Hormuz salt are thought to have had a fundamental control on the overall topography. | 0 | Salts |
Hypertonic saline—7% NaCl solutions are considered mucoactive agents and thus are used to hydrate thick secretions (mucus) in order to make it easier to cough up and out (expectorate). 3% hypertonic saline solutions are also used in critical care settings, acutely increased intracranial pressure, or severe hyponatremia. Inhalation of hypertonic saline has also been shown to help in other respiratory problems, specifically bronchiolitis. Hypertonic saline is currently recommended by the Cystic Fibrosis Foundation as a primary part of a cystic fibrosis treatment regimen.
An 11% solution of xylitol with 0.65% saline stimulates the washing of the nasopharynx and has an effect on the nasal pathogenic bacteria. This has been used in complementary and alternative medicine.
Hypertonic saline may be used in perioperative fluid management protocols to reduce excessive intravenous fluid infusions and lessen pulmonary complications. Hypertonic saline is used in treating hyponatremia and cerebral edema. Rapid correction of hyponatremia via hypertonic saline, or via any saline infusion > 40 mmol/L (Na+ having a valence of 1, 40 mmol/L = 40 mEq/L) greatly increases risk of central pontine myelinolysis (CPM), and so requires constant monitoring of the persons response. Water privation combined with diuretic block does not produce as much risk of CPM as saline administration does; however, it does not correct hyponatremia as rapidly as administration of hypertonic saline does. Due to hypertonicity, administration may result in phlebitis and tissue necrosis. As such, concentrations greater than 3% NaCl should normally be administered via a central venous catheter, also known as a central line'. Such hypertonic saline is normally available in two strengths, the former of which is more commonly administered:
* 3% NaCl has 513 mEq/L of Na and Cl.
* 5% NaCl has 856 mEq/L of Na and Cl.
Hypertonic NaCl solutions that are less commonly used are 7% (1200 mEq/L) and 23.4% (approx 4000 mEq/L), both of which are used (also via central line), often in conjunction with supplementary diuretics, in the treatment of traumatic brain injury. | 0 | Salts |
Sodium ethyl xanthate has moderate oral and dermal toxicity in animals and is irritating to eyes and skin. It is especially toxic to aquatic life and therefore its disposal is strictly controlled. Median lethal dose for (male albino mice, oral, 10% solution at pH~11) is 730 mg/kg of body weight, with most deaths occurring in the first day. The most affected organs were the central nervous system, liver and spleen.
Since 1993, sodium ethyl xanthate is classified as a Priority Existing Chemical in Australia, meaning that its manufacture, handling, storage, use or disposal may result in adverse health or environment effects. This decision was justified by the widespread use of the chemical in industry and its decomposition to the toxic and flammable carbon disulfide gas. From two examples of sodium ethyl xanthate spillage in Australia, one resulted in evacuation of 100 people and hospitalization of 6 workers who were exposed to the fumes. In another accident, residents of the spillage area complained of headache, dizziness, and nausea. Consequently, during high-risk sodium ethyl xanthate handling operations, workers are required by the Australian regulations to be equipped with protective clothing, anti-static gloves, boots and full-face respirators or self-contained breathing apparatus. | 0 | Salts |
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Wikipedia Salts vs Semiconductor Materials Binary Classification
This dataset is derived from the English Wikipedia articles and is designed for binary text classification tasks in the fields of chemistry and materials science. The dataset is divided into two classes based on the thematic content of the articles:
- Salts: This class includes articles that focus on salts, which are ionic compounds composed of cations and anions. Topics may cover the properties, types, synthesis, and applications of various salts in different fields such as chemistry, biology, and industry.
- Semiconductor Materials: This class comprises articles related to semiconductor materials, which have electrical conductivity between that of a conductor and an insulator. Topics may include the properties, types, synthesis, and applications of semiconductor materials in electronics, photovoltaics, and other technologies.
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