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are vector spherical harmonics normalized so that The multipole expansion of the electromagnetic field finds application in a number of problems involving spherical symmetry, for example antennae radiation patterns, or nuclear gamma decay. In these applications, one is often interested in the power radiated in the far...	Electromagnetic wave equation	Wikipedia	84	2924436	https://en.wikipedia.org/wiki/Electromagnetic%20wave%20equation	Physical sciences	Electromagnetic radiation	Physics
Radiative transfer (also called radiation transport) is the physical phenomenon of energy transfer in the form of electromagnetic radiation. The propagation of radiation through a medium is affected by absorption, emission, and scattering processes. The equation of radiative transfer describes these interactions mathem...	Radiative transfer	Wikipedia	470	2925371	https://en.wikipedia.org/wiki/Radiative%20transfer	Physical sciences	Electromagnetic radiation	Physics
Solutions to the equation of radiative transfer Solutions to the equation of radiative transfer form an enormous body of work. The differences however, are essentially due to the various forms for the emission and absorption coefficients. If scattering is ignored, then a general steady state solution in terms of the e...	Radiative transfer	Wikipedia	501	2925371	https://en.wikipedia.org/wiki/Radiative%20transfer	Physical sciences	Electromagnetic radiation	Physics
Thus the Eddington approximation is equivalent to setting . Higher order versions of the Eddington approximation also exist, and consist of more complicated linear relations of the intensity moments. This extra equation can be used as a closure relation for the truncated system of moments. Note that the first two mome...	Radiative transfer	Wikipedia	193	2925371	https://en.wikipedia.org/wiki/Radiative%20transfer	Physical sciences	Electromagnetic radiation	Physics
Temnospondyli (from Greek τέμνειν, temnein 'to cut' and σπόνδυλος, spondylos 'vertebra') or temnospondyls is a diverse ancient order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian and Triassic periods, with fossils being found on every conti...	Temnospondyli	Wikipedia	428	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Experts disagree over whether temnospondyls were ancestral to modern amphibians (frogs, salamanders and caecilians), or whether the whole group died out without leaving any descendants. Different hypotheses have placed modern amphibians as the descendants of temnospondyls, as descendants of another group of early tetra...	Temnospondyli	Wikipedia	413	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Many temnospondyls are much larger than living amphibians, and superficially resemble crocodiles, which has led many taxa to be named with the suffix -suchus. The largest taxa, which were predominantly the Mesozoic stereospondyls, had skulls exceeding one meter in length, and the entire animal would have been several m...	Temnospondyli	Wikipedia	130	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Cranium Skulls are generally parabolic to triangular in shape when viewed from above, and they were particularly flattened in semiaquatic to aquatic taxa, with dorsally facing orbits. The skull is usually covered in pits and ridges to form a honeycomb-like pattern. One of the most recent hypotheses for the function of...	Temnospondyli	Wikipedia	407	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Homologues of most of the bones of temnospondyls are also seen in other early tetrapods, aside from a few bones in the skull, such as interfrontals, internasals and interparietals, that have developed in some temnospondyl taxa. The intertemporal, a bone common in stem tetrapods, is only found in some late Paleozoic tax...	Temnospondyli	Wikipedia	491	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Temnospondyls' vertebrae are divided into several segments. In living tetrapods, the main body of the vertebra is a single piece of bone called the centrum, but in temnospondyls, this region was divided into a pleurocentrum and intercentrum. Two primary types of vertebrae are recognized in temnospondyls: stereospondylo...	Temnospondyli	Wikipedia	472	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
The function of this sail, like that of the contemporaneous sphenacodontids and edaphosaurids, remains enigmatic, but it is thought to have stiffened the vertebral column in association with the relative terrestriality of this clade. Recent histological work has demonstrated that most of this hyperelongation is formed ...	Temnospondyli	Wikipedia	194	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
The pectoral girdle comprised an unpaired interclavicle, paired clavicles, paired cleithra, and paired scapulae / scapulocoracoids as with most other early tetrapods. These elements differ widely in variation across temnospondyls, with such variation attributed to different lifestyles. The interclavicle and clavicles t...	Temnospondyli	Wikipedia	427	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Unlike modern amphibians, many temnospondyls are covered in small, closely packed scales. The undersides of most temnospondyls are covered in rows of large ventral plates. During early stages of development, they first have only small, rounded scales. Fossils show, as the animals grew, the scales on the undersides of t...	Temnospondyli	Wikipedia	155	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Several groups of temnospondyls have large bony plates (osteoderms) on their backs. One temnospondyl, Peltobatrachus, has armour-like plating that covers both its back and underside. The rhytidosteid Laidleria also has extensive plating on its back. Most members of the family Dissorophidae also have armor, although it ...	Temnospondyli	Wikipedia	379	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Soft tissue Very little is known of the soft tissue of temnospondyls because the conditions necessary to preserve such material are uncommon. The most extensive records come from fine-grained deposits in the Carboniferous and Permian of Germany; the small-bodied and aquatic dissorophoids and the larger stereospondylom...	Temnospondyli	Wikipedia	345	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
The naming of these first specimens was disputed. Leopold Fitzinger named the animal Batrachosaurus in 1837. In 1841, the English paleontologist Richard Owen referred to the genus as Labyrinthodon to describe its highly folded or labyrinthine teeth. Owen thought that the name Mastodonsaurus "ought not to be retained, b...	Temnospondyli	Wikipedia	487	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
In addition to Mastodonsaurus, some of the earliest-named genera included Metopias and Rhombopholis in 1842, Zygosaurus in 1848, Trematosaurus in 1849, Baphetes and Dendrerpeton in 1853, Capitosaurus in 1858, and Dasyceps in 1859. Baphetes is now placed as an early tetrapod outside Temnospondyli, and Rhombopholis is no...	Temnospondyli	Wikipedia	291	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Several suborders of stegocephalians were recognized in the late 19th and early 20th centuries. Animals now regarded as temnospondyls were primarily labyrinthodonts, but some were classified in the Branchiosauria. Branchiosaurs were small-bodied and had simple conical teeth, while labyrinthodonts were larger and had co...	Temnospondyli	Wikipedia	495	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
By the end of the 19th century, most of what are today regarded as temnospondyls were placed in the suborder Labyrinthodonta. The American paleontologist Ermine Cowles Case called it Labyrinthodonta vera or "true labyrinthodonts". The names Stegocephalia and Labyrinthodontia were used interchangeably to refer to the or...	Temnospondyli	Wikipedia	506	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Temnospondyli became a commonly used name at the turn of the 20th century. Paleontologists included both embolomeres and rhachitomes in the group. Cope's Ganocephala and Labyrinthodonta fell out of use. In 1919, British paleontologist D. M. S. Watson proposed that the evolutionary history of these large amphibians coul...	Temnospondyli	Wikipedia	480	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Temnospondyls were also documented from an increasingly broad geographic and stratigraphic range in the 20th and 21st centuries, including the first occurrences from historically undersampled regions such as Antarctica, Lesotho, Japan, Namibia, New Zealand, Niger, and Türkiye. Evolutionary history Carboniferous and E...	Temnospondyli	Wikipedia	338	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Middle Permian (Guadalupian) Middle Permian records of temnospondyls are relatively sparse, and some of these are debated as a result of the uncertain age and correlation of different deposits in North America (Chickasha, Flowerpot Formations), Niger (Moradi Formation), Brazil (Rio do Rasto Formation), and Russia (Mez...	Temnospondyli	Wikipedia	380	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Triassic As temnospondyls continued to flourish and diversify in the Late Permian (260.4–251.0 Mya), a major group called Stereospondyli became more dependent on life in the water. The vertebrae became weak, the limbs small, and the skull large and flat, with the eyes facing upwards. During the Triassic period, these a...	Temnospondyli	Wikipedia	494	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Jurassic and Cretaceous Temnospondyls reached a peak diversity during the Early Triassic, and progressively declined throughout the subsequent Middle and Late Triassic, with only members of the Brachyopoidea and Trematosauroidea surviving into the Jurassic and the Cretaceous. Among brachyopoids, the brachyopids Gobiop...	Temnospondyli	Wikipedia	439	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Class Amphibia Order Temnospondyli Superfamily Edopoidea Family Cochleosauridae Family Edopidae Clade Eutemnospondyli Family Dendrerpetidae Clade Rhachitomi Suborder Dvinosauria Family Trimerorhachidae Superfamily Dvinosauroidea Family Dvinosauridae Family Eobrachyopidae Family Tupilakosauridae Superfamily Dissorophoi...	Temnospondyli	Wikipedia	479	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Phylogeny In one of the earliest phylogenetic analyses of the group, Gardiner (1983) recognized five characteristics that made Temnospondyli a clade: a bone at the back of the skull, the parasphenoid, is connected to another bone on the underside of the skull, the pterygoid; large openings called interpterygoid vacuiti...	Temnospondyli	Wikipedia	441	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Most phylogenetic analyses of temnospondyl interrelationships focus on individual families. One of the first broad-scale studies of temnospondyl phylogeny was conducted by paleontologist Andrew Milner in 1990. A 2007 study made a "supertree" of all temnospondyl families, combining the family-level trees of previous stu...	Temnospondyli	Wikipedia	431	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
In 2000, paleontologists Adam Yates and Anne Warren produced a revised phylogeny of more derived temnospondyls, naming several new clades. Two major clades were Euskelia and Limnarchia. Euskelia includes the temnospondyls that were once called rhachitomes and includes two subfamilies, the Dissorophoidea and the Eryopoi...	Temnospondyli	Wikipedia	275	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Within Stereospondyli, Yates and Warren erected two major clades: Capitosauria and Trematosauria. Capitosaurs include large semiaquatic temnospondyls like Mastodonsaurus with flat heads and eyes near the back of the skull. Trematosaurs include a diversity of temnospondyls, including large marine trematosaurids, aquatic...	Temnospondyli	Wikipedia	472	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Modern amphibians (frogs, salamanders and caecilians) are classified in Lissamphibia. Lissamphibians appear to have arisen in the Permian. Molecular clock estimates place the first lissamphibian in the Late Carboniferous, but the first member of Batrachia (frogs and salamanders, but not caecilians) is estimated to have...	Temnospondyli	Wikipedia	405	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
The dissorophoid family Amphibamidae is thought to be most closely related to Lissamphibia. In 2008, an amphibamid called Gerobatrachus hottoni was named from Texas and was nicknamed the "frogamander" for its frog-like head and salamander-like body. It was thought to be the most closely related temnospondyl to lissamph...	Temnospondyli	Wikipedia	358	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Chinlestegophis, a putative Triassic stereospondyl considered to be related to metoposauroids such as Rileymillerus, has been noted to share many features with caecilians, a living group of legless burrowing amphibians. If Chinlestegophis is indeed both an advanced stereospondyl and a relative of caecilians, this means...	Temnospondyli	Wikipedia	317	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Most aquatic stereospondyls have flattened heads. When feeding, they probably opened their mouths by lifting their skulls instead of lowering their lower jaws. The jaw mechanics of the plagiosaurid Gerrothorax is well known, and is one of the most highly adapted. Gerrothorax is thought to have lifted its skull to aroun...	Temnospondyli	Wikipedia	503	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Reproduction Temnospondyls, like most modern amphibians, reproduced in aquatic environments. Most temnospondyls probably reproduced through external fertilization. Like most living frogs, female temnospondyls would have laid masses of eggs in water while males released sperm to fertilize them. Several fossils were desc...	Temnospondyli	Wikipedia	421	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Body impressions of Early Carboniferous temnospondyls from Pennsylvania suggest that some terrestrial temnospondyls mated on land like some modern amphibians. They reproduced through internal fertilization rather than mating in water. The presence of three individuals in one block of sandstone shows that the temnospond...	Temnospondyli	Wikipedia	384	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Temnospondyls like Sclerocephalus are known from both large adult specimens and small larvae, showing an extreme change in body shape. In these species, the shape and proportions of skull bones change in the early stages of development. The ornamentation on the surface of the skull roof also develops at this time. Smal...	Temnospondyli	Wikipedia	422	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Studies of temnospondyl development have reached differing conclusions regarding what forms of gills were present in temnospondyls which possessed the organs. Although some species possessed external gills which were preserved as soft tissue, for many groups the type of gill can only be inferred from the structure of t...	Temnospondyli	Wikipedia	447	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
While most temnospondyls are aquatic in early stages of life, most metoposaurids appear to have been terrestrial in their juvenile stage. Like other Mesozoic temnospondyls, adult metoposaurids were adapted to a semiaquatic lifestyle. Their bones are not highly developed for movement on land. The cross-sectional thickne...	Temnospondyli	Wikipedia	506	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
The ability of the tympanum and stapes to effectively transmit vibrations is called impedance matching. Early tetrapods like temnospondyls have thick stapes with poor impedance matching, so it is now thought that they were not used for hearing. Instead, these thick stapes may have functioned to support the tissue that ...	Temnospondyli	Wikipedia	207	2925388	https://en.wikipedia.org/wiki/Temnospondyli	Biology and health sciences	Prehistoric amphibians	Animals
Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray me...	Cobalt	Wikipedia	505	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
The name cobalt derives from a type of ore considered a nuisance by 16th century German silver miners, which in turn may have been named from a spirit or goblin held superstitiously responsible for it; this spirit is considered equitable to the kobold (a household spirit) by some, or, categorized as a gnome (mine spiri...	Cobalt	Wikipedia	433	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Several oxides of cobalt are known. Green cobalt(II) oxide (CoO) has rocksalt structure. It is readily oxidized with water and oxygen to brown cobalt(III) hydroxide (Co(OH)3). At temperatures of 600–700 °C, CoO oxidizes to the blue cobalt(II,III) oxide (Co3O4), which has a spinel structure. Black cobalt(III) oxide (Co2...	Cobalt	Wikipedia	503	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Cobalt(III) forms a wide variety of coordination complexes with ammonia and amines, which are called ammine complexes. Examples include , (chloropentamminecobalt(III)), and cis- and trans-. The corresponding ethylenediamine complexes are also well known. Analogues are known where the halides are replaced by nitrite,...	Cobalt	Wikipedia	458	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
59Co is the only stable cobalt isotope and the only isotope that exists naturally on Earth. Twenty-two radioisotopes have been characterized: the most stable, 60Co, has a half-life of 5.2714 years; 57Co has a half-life of 271.8 days; 56Co has a half-life of 77.27 days; and 58Co has a half-life of 70.86 days. All the ot...	Cobalt	Wikipedia	509	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Grimms' dictionary entries equated the word "kobel" with "kobold", and listed it as a mere variant diminutive, but the latter is defined in it as a household spirit. Whereas some of the more recent commentators prefer to characterize the ore's namesake kobelt (recté kobel) as a gnome. The early 20th century Oxford Eng...	Cobalt	Wikipedia	473	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Cobalt compounds have been used for centuries to impart a rich blue color to glass, glazes, and ceramics. Cobalt has been detected in Egyptian sculpture, Persian jewelry from the third millennium BC, in the ruins of Pompeii, destroyed in 79 AD, and in China, dating from the Tang dynasty (618–907 AD) and the Ming dynast...	Cobalt	Wikipedia	415	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
During the 19th century, a significant part of the world's production of cobalt blue (a pigment made with cobalt compounds and alumina) and smalt (cobalt glass powdered for use for pigment purposes in ceramics and painting) was carried out at the Norwegian Blaafarveværket. The first mines for the production of smalt in...	Cobalt	Wikipedia	421	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Occurrence The stable form of cobalt is produced in supernovae through the r-process. It comprises 0.0029% of the Earth's crust. Except as recently delivered in meteoric iron, free cobalt (the native metal) is not found on Earth's surface because of its tendency to react with oxygen in the atmosphere. Small amounts of ...	Cobalt	Wikipedia	507	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Several methods exist to separate cobalt from copper and nickel, depending on the concentration of cobalt and the exact composition of the used ore. One method is froth flotation, in which surfactants bind to ore components, leading to an enrichment of cobalt ores. Subsequent roasting converts the ores to cobalt sulfat...	Cobalt	Wikipedia	509	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Glencore's Mutanda Mine shipped 24,500 tons of cobalt in 2016, 40% of Congo DRC's output and nearly a quarter of global production. After oversupply, Glencore closed Mutanda for two years in late 2019. Glencore's Katanga Mining project is resuming as well and should produce 300,000 tons of copper and 20,000 tons of cob...	Cobalt	Wikipedia	393	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
There is a push globally by the EU and major car manufacturers (OEM) for global production of cobalt to be sourced and –produced sustainably, responsibly and traceability of the supply chain. Mining companies are adopting and practising ESG initiatives in line with OECD Guidance and putting in place evidence of zero to...	Cobalt	Wikipedia	457	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
In December 2019, International Rights Advocates, a human rights NGO, filed a landmark lawsuit against Apple, Tesla, Dell, Microsoft and Google company Alphabet for "knowingly benefiting from and aiding and abetting the cruel and brutal use of young children" in mining cobalt. The companies in question denied their inv...	Cobalt	Wikipedia	511	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Applications In 2016, of cobalt was used. Cobalt has been used in the production of high-performance alloys. It is also used in some rechargeable batteries. Alloys Cobalt-based superalloys have historically consumed most of the cobalt produced. The temperature stability of these alloys makes them suitable for turbine...	Cobalt	Wikipedia	391	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
In 2018 most cobalt in batteries was used in a mobile device, a more recent application for cobalt is rechargeable batteries for electric cars. This industry increased five-fold in its demand for cobalt from 2016 to 2020, which made it urgent to find new raw materials in more stable areas of the world. Demand is expect...	Cobalt	Wikipedia	457	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Cobalt-based catalysts are used in reactions involving carbon monoxide. Cobalt is also a catalyst in the Fischer–Tropsch process for the hydrogenation of carbon monoxide into liquid fuels. Hydroformylation of alkenes often uses cobalt octacarbonyl as a catalyst. The hydrodesulfurization of petroleum uses a catalyst der...	Cobalt	Wikipedia	481	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Cobalt-60 has a radioactive half-life of 5.27 years. Loss of potency requires periodic replacement of the source in radiotherapy and is one reason why cobalt machines have been largely replaced by linear accelerators in modern radiation therapy. Cobalt-57 (Co-57 or 57Co) is a cobalt radioisotope most often used in medi...	Cobalt	Wikipedia	456	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Proteins based on cobalamin use corrin to hold the cobalt. Coenzyme B12 features a reactive C-Co bond that participates in the reactions. In humans, B12 has two types of alkyl ligand: methyl and adenosyl. MeB12 promotes methyl (−CH3) group transfers. The adenosyl version of B12 catalyzes rearrangements in which a hydro...	Cobalt	Wikipedia	447	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
The LD50 value for soluble cobalt salts has been estimated to be between 150 and 500 mg/kg. In the US, the Occupational Safety and Health Administration (OSHA) has designated a permissible exposure limit (PEL) in the workplace as a time-weighted average (TWA) of 0.1 mg/m3. The National Institute for Occupational Safety...	Cobalt	Wikipedia	261	24580536	https://en.wikipedia.org/wiki/Cobalt	Physical sciences	Chemical elements_2	null
Cerium is a chemical element; it has symbol Ce and atomic number 58. It is a soft, ductile, and silvery-white metal that tarnishes when exposed to air. Cerium is the second element in the lanthanide series, and while it often shows the oxidation state of +3 characteristic of the series, it also has a stable +4 state th...	Cerium	Wikipedia	393	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Physical Cerium is the second element of the lanthanide series. In the periodic table, it appears between the lanthanides lanthanum to its left and praseodymium to its right, and above the actinide thorium. It is a ductile metal with a hardness similar to that of silver. Its 58 electrons are arranged in the configurat...	Cerium	Wikipedia	431	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Chemical properties of the element Like the other lanthanides, cerium metal is a good reducing agent, having standard reduction potential of E = −2.34 V for the Ce/Ce couple. It tarnishes in air, forming a passivating oxide layer like iron rust. A centimeter-sized sample of cerium metal corrodes completely in about a y...	Cerium	Wikipedia	464	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Naturally occurring cerium is made up of four isotopes: Ce (0.19%), Ce (0.25%), Ce (88.4%), and Ce (11.1%). All four are observationally stable, though the light isotopes Ce and Ce are theoretically expected to undergo double electron capture to isotopes of barium, and the heaviest isotope 142Ce is expected to undergo ...	Cerium	Wikipedia	355	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
The rarity of the proton-rich 136Ce and 138Ce is explained by the fact that they cannot be made in the most common processes of stellar nucleosynthesis for elements beyond iron, the s-process (slow neutron capture) and the r-process (rapid neutron capture). This is so because they are bypassed by the reaction flow of t...	Cerium	Wikipedia	436	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Halides Cerium forms all four trihalides CeX (X = F, Cl, Br, I) usually by reaction of the oxides with the hydrogen halides. The anhydrous halides are pale-colored, paramagnetic, hygroscopic solids. Upon hydration, the trihalides convert to complexes containing aquo complexes [Ce(HO)]. Unlike most lanthanides, Ce form...	Cerium	Wikipedia	345	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
The compound ceric ammonium nitrate (CAN) is the most common cerium compound encountered in the laboratory. The six nitrate ligands bind as bidentate ligands. The complex is 12-coordinate, a high coordination number which emphasizes the large size of the Ce4+ ion. CAN is a popular oxidant in organic synthesis, both ...	Cerium	Wikipedia	430	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Cerium was discovered in Bastnäs in Sweden by Jöns Jakob Berzelius and Wilhelm Hisinger, and independently in Germany by Martin Heinrich Klaproth, both in 1803. Cerium was named by Berzelius after the asteroid Ceres, formally 1 Ceres, discovered two years earlier. Ceres was initially considered to be a planet at the ti...	Cerium	Wikipedia	468	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Occurrence and production Cerium is the most abundant of all the lanthanides and the 25th most abundant element, making up 68 ppm of the Earth's crust. This value is the same of copper, and cerium is even more abundant than common metals such as lead (13 ppm) and tin (2.1 ppm). Thus, despite its position as one of the...	Cerium	Wikipedia	365	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Bastnäsite, LnCOF, is usually lacking in thorium and the heavy lanthanides beyond samarium and europium, and hence the extraction of cerium from it is quite direct. First, the bastnäsite is purified, using dilute hydrochloric acid to remove calcium carbonate impurities. The ore is then roasted in the air to oxidize it ...	Cerium	Wikipedia	490	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Gas mantles and pyrophoric alloys The first use of cerium was in gas mantles, invented by Austrian chemist Carl Auer von Welsbach. In 1885, he had previously experimented with mixtures of magnesium, lanthanum, and yttrium oxides, but these gave green-tinted light and were unsuccessful. Six years later, he discovered t...	Cerium	Wikipedia	328	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
Pigments and phosphors The photostability of pigments can be enhanced by the addition of cerium, as it provides pigments with lightfastness and prevents clear polymers from darkening in sunlight. An example of a cerium compound used on its own as an inorganic pigment is the vivid red cerium(III) sulfide (cerium sulfid...	Cerium	Wikipedia	454	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
The early lanthanides have been found to be essential to some methanotrophic bacteria living in volcanic mudpots, such as Methylacidiphilum fumariolicum: lanthanum, cerium, praseodymium, and neodymium are about equally effective. Cerium is otherwise not known to have biological role in any other organisms, but is not v...	Cerium	Wikipedia	507	24580596	https://en.wikipedia.org/wiki/Cerium	Physical sciences	Chemical elements_2	null
The diving bell spider or water spider (Argyroneta aquatica) is the only species of spider known to live almost entirely under water. It is the only member of the genus Argyroneta. When out of the water, the spider ranges in colour from mid to dark brown, although the hairs on the abdomen give it a dark grey, velvet-li...	Diving bell spider	Wikipedia	505	953257	https://en.wikipedia.org/wiki/Diving%20bell%20spider	Biology and health sciences	Spiders	Animals
A. aquatica is able to remain submerged for prolonged periods of time due to the silk-based structure it constructs in order to retain an oxygen supply, named after the diving bell structure it resembles. The species range in size, although the size of females may be limited as they put more energy into building and ma...	Diving bell spider	Wikipedia	299	953257	https://en.wikipedia.org/wiki/Diving%20bell%20spider	Biology and health sciences	Spiders	Animals
Diving bell The appearance of the diving bell gave rise to the genus name Argyroneta, from the Greek "argyros" (ἄργυρος), meaning "silver", and "neta", a neologism (perhaps for *νητής) derived from the verb "neo" (νέω) "spin", intended to mean "spinner of silver". Both sexes build diving bell webs which are used for di...	Diving bell spider	Wikipedia	421	953257	https://en.wikipedia.org/wiki/Diving%20bell%20spider	Biology and health sciences	Spiders	Animals
Larger spiders are able to produce larger bubbles which have a consequently higher oxygen conductance, but all spiders of this species are able to enlarge their bells in response to increased oxygen demands in low aquatic P(O2) environments. These spiders voluntarily tolerate internal conditions of low oxygen, enlargin...	Diving bell spider	Wikipedia	215	953257	https://en.wikipedia.org/wiki/Diving%20bell%20spider	Biology and health sciences	Spiders	Animals
In optics, the image of an object is defined as the collection of focus points of light rays coming from the object. A real image is the collection of focus points made by converging rays, while a virtual image is the collection of focus points made by backward extensions of diverging rays. In other words, a virtual im...	Virtual image	Wikipedia	368	953369	https://en.wikipedia.org/wiki/Virtual%20image	Physical sciences	Optics	Physics
A plane mirror forms a virtual image positioned behind the mirror. Although the rays of light seem to come from behind the mirror, light from the source only exists in front of the mirror. The image in a plane mirror is not magnified (that is, the image is the same size as the object) and appears to be as far behind th...	Virtual image	Wikipedia	233	953369	https://en.wikipedia.org/wiki/Virtual%20image	Physical sciences	Optics	Physics
The emperor scorpion (Pandinus imperator) is a species of scorpion native to rainforests and savannas in West Africa. It is one of the largest scorpions in the world and lives for six to eight years. Its body is black, but like other scorpions it glows pastel green or blue under ultraviolet light. It is a popular speci...	Emperor scorpion	Wikipedia	490	953913	https://en.wikipedia.org/wiki/Emperor%20scorpion	Biology and health sciences	Scorpions	Animals
Emperor scorpions are often confused with a similar genus (Heterometrus), and are one of the most famous scorpions. Different ion channel toxins have been isolated from the venom of the emperor scorpion, including Pi1, Pi2, Pi3, Pi4 and Pi7. Habitat and distribution The emperor scorpion is an African rainforest speci...	Emperor scorpion	Wikipedia	392	953913	https://en.wikipedia.org/wiki/Emperor%20scorpion	Biology and health sciences	Scorpions	Animals
In computing, cache replacement policies (also known as cache replacement algorithms or cache algorithms) are optimizing instructions or algorithms which a computer program or hardware-maintained structure can utilize to manage a cache of information. Caching improves performance by keeping recent or often-used data it...	Cache replacement policies	Wikipedia	469	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Bélády's algorithm The most efficient caching algorithm would be to discard information which would not be needed for the longest time; this is known as Bélády's optimal algorithm, optimal replacement policy, or the clairvoyant algorithm. Since it is generally impossible to predict how far in the future information wi...	Cache replacement policies	Wikipedia	353	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
SIEVE SIEVE is a simple eviction algorithm designed specifically for web caches, such as key-value caches and Content Delivery Networks. It uses the idea of lazy promotion and quick demotion. Therefore, SIEVE does not update the global data structure at cache hits and delays the update till eviction time; meanwhile, ...	Cache replacement policies	Wikipedia	437	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
When A B C D is installed in the blocks with sequence numbers (increment 1 for each new access) and E is accessed, it is a miss and must be installed in a block. With the LRU algorithm, E will replace A because A has the lowest rank (A(0)). In the next-to-last step, D is accessed and the sequence number is updated. F i...	Cache replacement policies	Wikipedia	484	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
A B C D are placed in the cache, since there is space available. At the fifth access (E), the block which held D is replaced with E since this block was used most recently. At the next access (to D), C is replaced since it was the block accessed just before D. Segmented LRU (SLRU) An SLRU cache is divided into two se...	Cache replacement policies	Wikipedia	501	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
When there is access to a value (such as A) and it is not in the cache, it is loaded from memory and placed in the block where the arrows are pointing in the example. After that block is placed, the arrows are flipped to point the opposite way. A, B, C and D are placed; E replaces A as the cache fills because that was ...	Cache replacement policies	Wikipedia	352	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Least frequent recently used (LFRU) The least frequent recently used (LFRU) algorithm combines the benefits of LFU and LRU. LFRU is suitable for network cache applications such as ICN, CDNs, and distributed networks in general. In LFRU, the cache is divided into two partitions: privileged and unprivileged. The privile...	Cache replacement policies	Wikipedia	348	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
S3-FIFO This is a new eviction algorithm designed in 2023. Compared to existing algorithms, which mostly build on LRU (least-recently-used), S3-FIFO only uses three FIFO queues: a small queue occupying 10% of cache space, a main queue that uses 90% of the cache space, and a ghost queue that only stores object metadata...	Cache replacement policies	Wikipedia	466	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
On a cache miss, the line with an RRPV equal to the maximum possible RRPV is evicted; with 3-bit values, a line with an RRPV of 23 - 1 = 7 is evicted. If no lines have this value, all RRPVs in the set are increased by 1 until one reaches it. A tie-breaker is needed, and usually, it is the first line on the left. The in...	Cache replacement policies	Wikipedia	460	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Hawkeye Hawkeye attempts to emulate Bélády's algorithm by using past accesses by a PC to predict whether the accesses it produces generate cache-friendly (used later) or cache-averse accesses (not used later). It samples a number of non-aligned cache sets, uses a history of length and emulates Bélády's algorithm on t...	Cache replacement policies	Wikipedia	481	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Machine-learning policies A number of policies have attempted to use perceptrons, markov chains or other types of machine learning to predict which line to evict. Learning augmented algorithms also exist for cache replacement. Other policies Low inter-reference recency set (LIRS) LIRS is a page replacement algorit...	Cache replacement policies	Wikipedia	505	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Pannier Pannier is a container-based flash caching mechanism which identifies containers whose blocks have variable access patterns. Pannier has a priority-queue-based survival-queue structure to rank containers based on their survival time, which is proportional to live data in the container. Static analysis Static ...	Cache replacement policies	Wikipedia	211	954281	https://en.wikipedia.org/wiki/Cache%20replacement%20policies	Mathematics	Algorithms	null
Gonepteryx rhamni, commonly named the common brimstone, is a butterfly of the family Pieridae. It lives throughout the Palearctic zone and is commonly found across Europe, Asia, and North Africa. Across much of its range, it is the only species of its genus, and is therefore simply known locally as the brimstone. Its w...	Gonepteryx rhamni	Wikipedia	392	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
The common brimstone uses various environments for different stages of its life cycle. The butterfly inhabits wetlands during mating and breeding season, as they provide ideal areas for oviposition due to an abundance of host plants like the alder buckthorn. The common brimstone prefers laying eggs on younger host plan...	Gonepteryx rhamni	Wikipedia	378	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Oviposition The common brimstone is univoltine, meaning that it lays one generation of eggs each year. There are several ideal characteristics of the particular host plants chosen for oviposition. Adult brimstones lay eggs on the underside of the leaves of the two species of host plants, where they are less conspicuou...	Gonepteryx rhamni	Wikipedia	444	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Caterpillar The larvae of the common brimstone undergo five instars, initially having a length of 1.7 mm in the first instar and reaching up to 34.9 mm in length when fully grown. The caterpillars have a green colouration with white hairs and dark tubercules across its length. When they first hatch, they move to the t...	Gonepteryx rhamni	Wikipedia	393	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Migration The common brimstone undergoes some regional migration between hibernation and breeding areas throughout the year, as seen in the different chemical composition of butterflies across varying seasons and regions. In general, there is movement towards wetlands to reproduce. After the eggs hatch, develop, and p...	Gonepteryx rhamni	Wikipedia	442	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Both the larval and adult common brimstone exhibit cryptic colouration, meaning they match the colour of their habitats. Larvae are so difficult to see due to this colouration that they can remain in the open undetected. When not eating, the caterpillars remain still in a position alongside the midrib of leaves, making...	Gonepteryx rhamni	Wikipedia	448	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
In males, iridescence is indicated in that the wing pattern appears to visually change depending on the position of the ultraviolet light shone onto the wing. At some angles, a male pattern is seen, while at other angles, a female lack of pattern is seen. This is referred to as the "gynandromorphic effect". This demons...	Gonepteryx rhamni	Wikipedia	388	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Olfaction The common brimstone has an antennal response to the floral scent compounds of nectar plants, where neural activity in antennal olfactory receptors occurs in the presence of certain compounds. Research suggests that there are antennal olfactory receptors for phenylacetaldehyde and the terpene compounds oxois...	Gonepteryx rhamni	Wikipedia	456	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals
Conservation As of 2010, G. rhamni does not appear to have a threatened conservation status according to IUCN standards. However, the butterfly has experienced significant population and distribution reduction in areas such as the Netherlands, where its numbers have declined to the point that based on IUCN criterion, ...	Gonepteryx rhamni	Wikipedia	196	956001	https://en.wikipedia.org/wiki/Gonepteryx%20rhamni	Biology and health sciences	Lepidoptera	Animals

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