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to the oral microbiome, is associated with periodontal disease and has been linked with a wide variety of health outcomes, including unfavorable pregnancy outcomes. == Immune response == The immune response becomes more pronounced when bacteria are found that are not commensal. == History == Investigations into reprodu...	{ "page_id": 50925207, "title": "Uterine microbiome" }
by Dr. Inmaculada Moreno at the Carlos Simon Foundation studies the role of the endometrial microbiome in human reproduction. When research on the uterine microbiome was scarce, Dr. Moreno and her team analyzed the endometrial microbiota and discovered that there was a correlation between certain endometrial microbiota...	{ "page_id": 50925207, "title": "Uterine microbiome" }
Bánh tráng or bánh đa nem, a Vietnamese term (literally, coated bánh), sometimes called rice paper wrappers, rice crepes, rice wafers or nem wrappers, are edible Vietnamese wrappers used in Vietnamese cuisine, primarily in finger foods and appetizers such as Vietnamese nem dishes. The term rice paper wrappers can somet...	{ "page_id": 3477144, "title": "Bánh tráng" }
Some can be thicker than the standard rice wrapper and can also include sesame seeds. It is often used in dishes like mì Quảng as a topping. Not to be confused with the street food dish from Đà Lạt (also known as Vietnamese pizza or quesadilla) with the same name. === Bánh đa nem (vỏ ram / bánh ram) === This is a north...	{ "page_id": 3477144, "title": "Bánh tráng" }
from only tapioca starch. They are dried and translucent and are more sticky when activated with water. === Bánh tráng chuối (Banana flavored banh trang) === These banh trang wrappers are typically made by adding bananas. Its texture resembles that of a rice cracker. === Bánh tráng dừa (Coconut flavored banh trang) ===...	{ "page_id": 3477144, "title": "Bánh tráng" }
are typically baked or soaked in water, depending on individual textural preference, then served with salads, mi Quang and various other dishes. == Outside Vietnam == Banh trang wrappers are found in countries outside Vietnam with Vietnamese diaspora (people who leave Vietnam). == References ==	{ "page_id": 3477144, "title": "Bánh tráng" }
Immunoelectrophoresis is a general name for a number of biochemical methods for separation and characterization of proteins based on electrophoresis and reaction with antibodies. All variants of immunoelectrophoresis require immunoglobulins, also known as antibodies, reacting with the proteins to be separated or charac...	{ "page_id": 2428570, "title": "Immunoelectrophoresis" }
classical method of immunoelectrophoresis. Proteins are separated by electrophoresis, then antibodies are applied in a trough next to the separated proteins and immunoprecipitates are formed after a period of diffusion of the separated proteins and antibodies against each other. The introduction of the immunoelectropho...	{ "page_id": 2428570, "title": "Immunoelectrophoresis" }
with other macromolecules or ligands. Affinity immunoelectrophoresis has been used for estimation of binding constants, as for instance with lectins or for characterization of proteins with specific features like glycan content or ligand binding. Some variants of affinity immunoelectrophoresis are similar to affinity c...	{ "page_id": 2428570, "title": "Immunoelectrophoresis" }
in the precipitated zone, according to the findings. The capability of the amphiphilic fluorescein copolymer to boost antigen-antibody association and see the fluorescent accumulation domain may improve the efficiency of counter-immunoelectrophoresis for infectious disease rapid diagnosis. Immunomethods The terminologi...	{ "page_id": 2428570, "title": "Immunoelectrophoresis" }
researching nanoparticles before in vivo delivery, because it will impact nanoparticle longevity, destination, and bio-distribution. This method employs two-dimensional horizontally agarose protein electrophoresis to specifically identify the association of nanoparticles with the C3 protein. Proteins can be separated i...	{ "page_id": 2428570, "title": "Immunoelectrophoresis" }
Cytochrome P450, family 25, also known as CYP25, is a nematoda cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP25A1 from the Caenorhabditis elegans. == References ==	{ "page_id": 69275290, "title": "CYP25 family" }
Probabilistic genotyping is the use of statistical methods and mathematical algorithms in DNA Profiling. It may be used instead of manual methods in difficult situations, such as when a DNA sample is very small or includes a mixture of multiple individuals' DNA. Probabilistic genotyping, unlike traditional methods, avo...	{ "page_id": 60165786, "title": "Probabilistic genotyping" }
This is a list of molecules that have been detected in the interstellar medium and circumstellar envelopes, grouped by the number of component atoms. The chemical formula is listed for each detected compound, along with any ionized form that has also been observed. == Background == The molecules listed below were detec...	{ "page_id": 921245, "title": "List of interstellar and circumstellar molecules" }
of the spectral lines. If the molecule exists in multiple isotopologues (versions containing different atomic isotopes), the spectrum is further complicated by isotope shifts. Detection of a new interstellar or circumstellar molecule requires identifying a suitable astronomical object where it is likely to be present, ...	{ "page_id": 921245, "title": "List of interstellar and circumstellar molecules" }
of the largest molecules were first detected in another molecular cloud, TMC-1. A rich source of circumstellar molecules is CW Leonis (also known as IRC +10216), a nearby carbon star, where about 50 molecules have been identified. There is no clear boundary between interstellar and circumstellar media, so both are incl...	{ "page_id": 921245, "title": "List of interstellar and circumstellar molecules" }
section header. Most of the molecules detected so far are organic. The only detected inorganic molecule with five or more atoms is SiH4. Molecules larger than that all have at least one carbon atom, with no N−N or O−O bonds. === Diatomic (45) === === Triatomic (45) === === Four atoms (31) === === Five atoms (21) === ==...	{ "page_id": 921245, "title": "List of interstellar and circumstellar molecules" }
Oxidation and reduction in red wines can lead to a particularly undesirable brick red color in red wines (or an "orangey" color in white wines). This process is sometimes referred to as browning. In chemical terms, this is called a redox reaction because first the color of the wine deepens after fermentation through ox...	{ "page_id": 55840419, "title": "Browning in red wine" }
on their opinion of the wine. In a primitive sense, visual cues will generally have a stronger impact on humans than aromatic components since humans have evolved to identify things with eyesight, rather than through scent relative to other evolved species that rely on different sensory capacities more than they do on ...	{ "page_id": 55840419, "title": "Browning in red wine" }
The metallicity distribution function is an important concept in stellar and galactic evolution. It is a curve of what proportion of stars have a particular metallicity ([Fe/H], the relative abundance of iron and hydrogen) of a population of stars such as in a cluster or galaxy. MDFs are used to test different theories...	{ "page_id": 37555875, "title": "Metallicity distribution function" }
Oxamic acid is an organic compound with the formula NH2C(O)COOH. It is a white, water-soluble solid. It is the monoamide of oxalic acid. Oxamic acid inhibits lactate dehydrogenase A. The active site of lactate dehydrogenase (LDH) is closed off once oxamic acid attaches to the LDH-NADH complex, effectively inhibiting it...	{ "page_id": 52432551, "title": "Oxamic acid" }
Electrochemical energy conversion is a field of energy technology concerned with electrochemical methods of energy conversion including fuel cells and photoelectrochemical. This field of technology also includes electrical storage devices like batteries and supercapacitors. It is increasingly important in context of au...	{ "page_id": 31002280, "title": "Electrochemical energy conversion" }
Retene, methyl isopropyl phenanthrene or 1-methyl-7-isopropyl phenanthrene, C18H18, is a polycyclic aromatic hydrocarbon present in the coal tar fraction, boiling above 360 °C. It occurs naturally in the tars obtained by the distillation of resinous woods. It crystallizes in large plates, which melt at 98.5 °C and boil...	{ "page_id": 2952874, "title": "Retene" }
Hexanone may refer to the following ketones containing six carbon atoms: 2-Hexanone (Methyl butyl ketone, MBK) 4-Methyl-2-pentanone (Methyl isobutyl ketone, MIBK) 3-Methyl-2-pentanone (Methyl sec-butyl ketone) 3,3-Dimethyl-2-butanone (Methyl tert-butyl ketone, Pinacolone) 3-Hexanone (Ethyl propyl ketone) 2-Methyl-3-pen...	{ "page_id": 19861162, "title": "Hexanone" }
The Chemical History of a Candle was the title of a series of six lectures on the chemistry and physics of flames given by Michael Faraday at the Royal Institution in 1848, as part of the series of Christmas lectures for young people founded by Faraday in 1825 and still given there every year. The lectures described th...	{ "page_id": 2690730, "title": "The Chemical History of a Candle" }
Hydrogen in the Candle - Burns into Water - The Other Part of Water - Oxygen Lecture 5: Oxygen present in the Air - Nature of the Atmosphere - Its Properties - Other Products from the Candle - Carbonic Acid - Its Properties Lecture 6: Carbon or Charcoal - Coal Gas Respiration and its Analogy to the Burning of a Candle ...	{ "page_id": 2690730, "title": "The Chemical History of a Candle" }
what science is about", such as the works of James Jeans. Faraday in contrast explains the difficulties and details of experiments. == References == == External links == Faraday, Michael (1861). W. Crookes (ed.). A Course of Six Lectures on the Chemical History of a Candle. Griffin, Bohn & Co. Full text of The Chemical...	{ "page_id": 2690730, "title": "The Chemical History of a Candle" }
ABALDH may refer to: Aminobutyraldehyde dehydrogenase, an enzyme 1-pyrroline dehydrogenase, an enzyme	{ "page_id": 21302955, "title": "ABALDH" }
Boron is a chemical element; it has symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the boron group it has three valence electrons for forming covalent bonds, resulting in many compounds such as boric...	{ "page_id": 3755, "title": "Boron" }
A small amount is used as a dopant in semiconductors, and reagent intermediates in the synthesis of organic fine chemicals. A few boron-containing organic pharmaceuticals are used or are in study. Natural boron is composed of two stable isotopes, one of which (boron-10) has a number of uses as a neutron-capturing agent...	{ "page_id": 3755, "title": "Boron" }
a brown precipitate on one of the electrodes. In his subsequent experiments, he used potassium to reduce boric acid instead of electrolysis. He produced enough boron to confirm a new element and named it boracium. Gay-Lussac and Thénard used iron to reduce boric acid at high temperatures. By oxidizing boron with air, t...	{ "page_id": 3755, "title": "Boron" }
is ⁠3/2⁠. These isotopes are, therefore, of use in nuclear magnetic resonance spectroscopy; and spectrometers specially adapted to detecting the boron-11 nuclei are available commercially. The 10B and 11B nuclei also cause splitting in the resonances of attached nuclei. === Allotropes === Boron forms four major allotro...	{ "page_id": 3755, "title": "Boron" }
the reduction of boric oxide with metals such as magnesium or aluminium. However, the product was often contaminated with borides of those metals. Pure boron can be prepared by reducing volatile boron halides with hydrogen at high temperatures. Ultrapure boron for use in the semiconductor industry is produced by the de...	{ "page_id": 3755, "title": "Boron" }
to form homoatomic Al-Al bonds. In the most familiar compounds, boron has the formal oxidation state III. These include the common oxides, sulfides, nitrides, and halides, as well as organic derivatives Boron compounds often violate the octet rule. === Halides === Boron forms the complete series of trihalides, i.e. BX3...	{ "page_id": 3755, "title": "Boron" }
preservatives and fire retardants: 4ZnO·B2O3·H2O, ZnO·B2O3·1.12H2O, ZnO·B2O3·2H2O, 6ZnO·5B2O3·3H2O, 2ZnO·3B2O3·7H2O, 2ZnO·3B2O3·3H2O, 3ZnO·5B2O3·14H2O, and ZnO·5B2O3·4.5H2O. As illustrated by the preceding examples, borate anions tend to condense by formation of B-O-B bonds. Borosilicates, with B-O-Si, and borophosphat...	{ "page_id": 3755, "title": "Boron" }
are their structures unusual, many of the boranes are extremely reactive. For example, a widely used procedure for pentaborane states that it will "spontaneously inflame or explode in air". === Organoboron compounds === A large number of organoboron compounds, species with B-C bonds, are known. Many organoboron compoun...	{ "page_id": 3755, "title": "Boron" }
(tradename Borazon), boron and nitrogen atoms are tetrahedral, just like carbon in diamond. Cubic boron nitride, among other applications, is used as an abrasive, as its hardness is comparable with that of diamond. Hexagonal boron nitride (h-BN) is the BN analogue of graphite, consisting of sheets of alternating B and ...	{ "page_id": 3755, "title": "Boron" }
is negligible. Boron is not generated in the normal course of stellar nucleosynthesis and is destroyed in stellar interiors. In the high oxygen environment of the Earth's surface, boron is always found fully oxidized to borate. Boron does not appear on Earth in elemental form. Extremely small traces of elemental boron ...	{ "page_id": 3755, "title": "Boron" }
cost of crystalline elemental boron is US$5/g. Elemental boron is chiefly used in making boron fibers, where it is deposited by chemical vapor deposition on a tungsten core (see below). Boron fibers are used in lightweight composite applications, such as high strength tapes. This use is a very small fraction of total b...	{ "page_id": 3755, "title": "Boron" }
to reach 21 million tonnes by 2010. The highest growth in demand is expected to be in Asia where demand could rise by an average 5.7% per year. == Applications == Nearly all boron ore extracted from the Earth is refined as boric acid and sodium tetraborate pentahydrate. In the United States, 70% of the boron is used fo...	{ "page_id": 3755, "title": "Boron" }
glass, used both in laboratory glassware and in consumer cookware and bakeware, chiefly for this resistance. === Elemental boron fiber === Boron fibers (boron filaments) are high-strength, lightweight materials that are used chiefly for advanced aerospace structures as a component of composite materials, as well as lim...	{ "page_id": 3755, "title": "Boron" }
increase hardenability. Higher percentages are added to steels used in the nuclear industry due to boron's neutron absorption ability. Boron can also increase the surface hardness of steels and alloys through boriding. Additionally metal borides are used for coating tools through chemical vapor deposition or physical v...	{ "page_id": 3755, "title": "Boron" }
electron than the host atom, it donates a hole resulting in p-type conductivity. Traditional method of introducing boron into semiconductors is via its atomic diffusion at high temperatures. This process uses either solid (B2O3), liquid (BBr3), or gaseous boron sources (B2H6 or BF3). However, after the 1970s, it was mo...	{ "page_id": 3755, "title": "Boron" }
of its distinctive green flame, amorphous boron is used in pyrotechnic flares. Some anti-corrosion systems contain borax. Sodium borates are used as a flux for soldering silver and gold and with ammonium chloride for welding ferrous metals. They are also fire retarding additives to plastics and rubber articles. Boric a...	{ "page_id": 3755, "title": "Boron" }
have been used as eye antiseptics. Bortezomib (marketed as Velcade and Cytomib). Boron appears as an active element in the organic pharmaceutical bortezomib, a new class of drug called the proteasome inhibitor, for treating myeloma and one form of lymphoma (it is currently in experimental trials against other types of ...	{ "page_id": 3755, "title": "Boron" }
luminosity version of the Large Hadron Collider. === Commercial isotope enrichment === Because of its high neutron cross-section, boron-10 is often used to control fission in nuclear reactors as a neutron-capturing substance. Several industrial-scale enrichment processes have been developed; however, only the fractiona...	{ "page_id": 3755, "title": "Boron" }
shielding and is the primary nuclide used in neutron capture therapy of cancer. In the latter ("boron neutron capture therapy" or BNCT), a compound containing 10B is incorporated into a pharmaceutical which is selectively taken up by a malignant tumor and tissues near it. The patient is then treated with a beam of low ...	{ "page_id": 3755, "title": "Boron" }
normal tissues. When these 10B-containing cells are irradiated with low-energy thermal neutrons, they undergo nuclear capture reactions, releasing high linear energy transfer (LET) particles such as α-particles and lithium-7 nuclei within a limited path length. These high-LET particles can destroy the adjacent tumor ce...	{ "page_id": 3755, "title": "Boron" }
limitations and cost-effectively improve patient outcomes. == Biological role == Boron is an essential plant nutrient, required primarily for maintaining the integrity of cell walls. However, high soil concentrations of greater than 1.0 ppm lead to marginal and tip necrosis in leaves as well as poor overall growth perf...	{ "page_id": 3755, "title": "Boron" }
the existing data insufficient to derive a Recommended Dietary Allowance (RDA), Adequate Intake (AI), or Estimated Average Requirement (EAR) for boron and the U.S. Food and Drug Administration (FDA) has not established a daily value for boron for food and dietary supplement labeling purposes. While low boron status can...	{ "page_id": 3755, "title": "Boron" }
food records from the respondents to the Third National Health and Nutrition Examination Survey (NHANES III), adult dietary intake was recorded at 0.9 to 1.4 mg/day. === Health issues and toxicity === Elemental boron, boron oxide, boric acid, borates, and many organoboron compounds are relatively nontoxic to humans and...	{ "page_id": 3755, "title": "Boron" }
but it can be confused with other stresses such as magnesium deficiency in other plants. == See also == == Notes == == References == == External links == Boron at The Periodic Table of Videos (University of Nottingham) J. B. Calvert: Boron, 2004, private website (archived version)	{ "page_id": 3755, "title": "Boron" }
The molecular formula C9H8O4 (molar mass: 180.15 g/mol, exact mass: 180.0423 u) may refer to: Acetozone Aspirin 4-Hydroxyphenylpyruvic acid, a natural phenol Dihydroxycinnamic acids: Caffeic acid (3,4-Dihydroxycinnamic acid) Umbellic acid (2,4-dihydroxycinnamic acid) 2,3-Dihydroxycinnamic acid 2,5-Dihydroxycinnamic aci...	{ "page_id": 13766319, "title": "C9H8O4" }
Meprin A (EC 3.4.24.18, endopeptidase-2, meprin-a, meprin, N-benzoyl-L-tyrosyl-p-aminobenzoic acid hydrolase, PABA-peptide hydrolase, PPH) is an enzyme that cleaves protein and peptide substrates preferentially on carboxyl side of hydrophobic residues. This metalloprotease can be associated with inflammatory responses....	{ "page_id": 30740145, "title": "Meprin A" }
Bromine is a chemical element; it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825...	{ "page_id": 3756, "title": "Bromine" }
are toxic from the action of soluble bromide ions, causing bromism. However, bromine is beneficial for human eosinophils, and is an essential trace element for collagen development in all animals. Hundreds of known organobromine compounds are generated by terrestrial and marine plants and animals, and some serve import...	{ "page_id": 3756, "title": "Bromine" }
presented at a lecture of the Académie des Sciences and published in Annales de Chimie et Physique. In his publication, Balard stated that he changed the name from muride to brôme on the proposal of M. Anglada. The name brôme (bromine) derives from the Greek βρῶμος (brômos, "stench"). Other sources claim that the Frenc...	{ "page_id": 3756, "title": "Bromine" }
strong oxidising agent, reacting with many elements in order to complete its outer shell. Corresponding to periodic trends, it is intermediate in electronegativity between chlorine and iodine (F: 3.98, Cl: 3.16, Br: 2.96, I: 2.66), and is less reactive than chlorine and more reactive than iodine. It is also a weaker ox...	{ "page_id": 3756, "title": "Bromine" }
°C and boils at 58.8 °C. (Iodine is a shiny black solid.) This trend occurs because the wavelengths of visible light absorbed by the halogens increase down the group. Specifically, the colour of a halogen, such as bromine, results from the electron transition between the highest occupied antibonding πg molecular orbita...	{ "page_id": 3756, "title": "Bromine" }
to occur in nature. Of these, the most important are 80Br (t1/2 = 17.7 min), 80mBr (t1/2 = 4.421 h), and 82Br (t1/2 = 35.28 h), which may be produced from the neutron activation of natural bromine. The most stable bromine radioisotope is 77Br (t1/2 = 57.04 h). The primary decay mode of isotopes lighter than 79Br is ele...	{ "page_id": 3756, "title": "Bromine" }
bromide in the laboratory: 2 P + 6 H2O + 3 Br2 → 6 HBr + 2 H3PO3 H3PO3 + H2O + Br2 → 2 HBr + H3PO4 At room temperature, hydrogen bromide is a colourless gas, like all the hydrogen halides apart from hydrogen fluoride, since hydrogen cannot form strong hydrogen bonds to the large and only mildly electronegative bromine ...	{ "page_id": 3756, "title": "Bromine" }
=== Other binary bromides === Nearly all elements in the periodic table form binary bromides. The exceptions are decidedly in the minority and stem in each case from one of three causes: extreme inertness and reluctance to participate in chemical reactions (the noble gases, with the exception of xenon in the very unsta...	{ "page_id": 3756, "title": "Bromine" }
°C → 240 °C 3 WBr4 + AlBr3 EuBr3 + ⁠1/2⁠ H2 → EuBr2 + HBr 2 TaBr4 500 °C→ TaBr3 + TaBr5 Most metal bromides with the metal in low oxidation states (+1 to +3) are ionic. Nonmetals tend to form covalent molecular bromides, as do metals in high oxidation states from +3 and above. Both ionic and covalent bromides are known...	{ "page_id": 3756, "title": "Bromine" }
X = –CO2Et, –CHO, –NO2); this is due to heterolytic fission of the Br–F bond, leading to rapid electrophilic bromination by Br+. At room temperature, bromine trifluoride (BrF3) is a straw-coloured liquid. It may be formed by directly fluorinating bromine at room temperature and is purified through distillation. It reac...	{ "page_id": 3756, "title": "Bromine" }
was once thought that they could not exist at all. Dibromine monoxide is a dark-brown solid which, while reasonably stable at −60 °C, decomposes at its melting point of −17.5 °C; it is useful in bromination reactions and may be made from the low-temperature decomposition of bromine dioxide in a vacuum. It oxidises iodi...	{ "page_id": 3756, "title": "Bromine" }
Br− + 6 H+ → 3 Br2 + 3 H2O There were many failed attempts to obtain perbromates and perbromic acid, leading to some rationalisations as to why they should not exist, until 1968 when the anion was first synthesised from the radioactive beta decay of unstable 83SeO2−4. Today, perbromates are produced by the oxidation of...	{ "page_id": 3756, "title": "Bromine" }
common organohalides in nature, even though the concentration of bromide is only 0.3% of that for chloride in sea water, because of the easy oxidation of bromide to the equivalent of Br+, a potent electrophile. The enzyme bromoperoxidase catalyzes this reaction. The oceans are estimated to release 1–2 million tons of b...	{ "page_id": 3756, "title": "Bromine" }
available and has a long shelf life. == Applications == A wide variety of organobromine compounds are used in industry. Some are prepared from bromine and others are prepared from hydrogen bromide, which is obtained by burning hydrogen in bromine. === Flame retardants === Brominated flame retardants represent a commodi...	{ "page_id": 3756, "title": "Bromine" }
they are expensive and their production and use has been greatly curtailed due to their effect as ozone-depleting agents. They are no longer used in routine fire extinguishers, but retain niche uses in aerospace and military automatic fire suppression applications. They include bromochloromethane (Halon 1011, CH2BrCl),...	{ "page_id": 3756, "title": "Bromine" }
general sedatives in the 19th and early 20th century. Bromides in the form of simple salts are still used as anticonvulsants in both veterinary and human medicine, although the latter use varies from country to country. For example, the U.S. Food and Drug Administration (FDA) does not approve bromide for the treatment ...	{ "page_id": 3756, "title": "Bromine" }
sun. For indoor pools, it can be a good option as it is effective at a wider pH range. It is also more stable in a heated pool or hot tub. == Biological role and toxicity == A 2014 study suggests that bromine (in the form of bromide ion) is a necessary cofactor in the biosynthesis of collagen IV, making the element ess...	{ "page_id": 3756, "title": "Bromine" }
Hawaiian alga Asparagopsis taxiformis consists of 80% bromoform. Most of such organobromine compounds in the sea are made by the action of a unique algal enzyme, vanadium bromoperoxidase. The bromide anion is not very toxic: a normal daily intake is 2 to 8 milligrams. However, high levels of bromide chronically impair ...	{ "page_id": 3756, "title": "Bromine" }
to bromine immediately dangerous to life and health (IDLH) is 3 ppm. Bromine is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities wh...	{ "page_id": 3756, "title": "Bromine" }
Barium is a chemical element; it has symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. The most common minerals of barium are barite (barium sulfate, BaSO4) and withe...	{ "page_id": 3757, "title": "Barium" }
heating at a rate of approximately 1.8×10−5/°C.: 2 It is a soft metal with a Mohs hardness of 1.25.: 2 Its melting temperature of 1,000 K (730 °C; 1,340 °F): 4–43 is intermediate between those of the lighter strontium (1,050 K or 780 °C or 1,430 °F): 4–86 and heavier radium (973 K or 700 °C or 1,292 °F);: 4–78 however,...	{ "page_id": 3757, "title": "Barium" }
or calcium analogs, except for the halides (see table; zinc is given for comparison). Barium hydroxide ("baryta") was known to alchemists, who produced it by heating barium carbonate. Unlike calcium hydroxide, it absorbs very little CO2 in aqueous solutions and is therefore insensitive to atmospheric fluctuations. This...	{ "page_id": 3757, "title": "Barium" }
stones". Alchemists were attracted to them because after exposure to light they would glow for years. The phosphorescent properties of baryte heated with organics were described by V. Casciorolus in 1602.: 5 Carl Scheele determined that baryte contained a new element in 1772, but could not isolate barium, only barium o...	{ "page_id": 3757, "title": "Barium" }
many parts of the world. Another commercial source, far less important than baryte, is witherite, barium carbonate. The main deposits are located in Britain, Romania, and the former USSR.: 5 The baryte reserves are estimated between 0.7 and 2 billion tonnes. The highest production, 8.3 million tonnes, was achieved in 1...	{ "page_id": 3757, "title": "Barium" }
remaining barium oxide reacts with the formed aluminium oxide:: 3 BaO + Al2O3 → BaAl2O4 and the overall reaction is: 3 4 BaO + 2 Al → 3 Ba↓ + BaAl2O4 Barium vapor is condensed and packed into molds in an atmosphere of argon.: 3 This method is used commercially, yielding ultrapure barium.: 3 Commonly sold barium is abou...	{ "page_id": 3757, "title": "Barium" }
gases by dissolving them in the crystal lattice. This application is gradually disappearing due to the rising popularity of the tubeless LCD, LED, and plasma sets.: 4 Other uses of elemental barium are minor and include an additive to silumin (aluminium–silicon alloys) that refines their structure, as well as: 4 bearin...	{ "page_id": 3757, "title": "Barium" }
screens.: 12–13 Barium, typically as barium nitrate imparts a yellow or "apple" green color to fireworks when no chlorine donors are present.; emerald greens are generated using chlorine donors (barium chlorate acting as the donor and oxidizer in many formulas) to produce barium chloride in-situ. Barium peroxide is a c...	{ "page_id": 3757, "title": "Barium" }
(water column, sediments, and hydrothermal sites). In each setting there are differences in isotopic and elemental composition of the barite particulate. Barite in the water column, known as marine or pelagic barite, reveals information on seawater chemistry variation over time. Barite in sediments, known as diagenetic...	{ "page_id": 3757, "title": "Barium" }
Berkelium is a synthetic chemical element; it has symbol Bk and atomic number 97. It is a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the Lawrence Berkeley National Laboratory (then the University of California Radiation Laboratory) where i...	{ "page_id": 3758, "title": "Berkelium" }
the formation of californium brings not only chemical contamination, but also free-radical effects and self-heating from the emitted alpha particles. == Characteristics == === Physical === Berkelium is a soft, silvery-white, radioactive actinide metal. In the periodic table, it is located to the right of the actinide c...	{ "page_id": 3758, "title": "Berkelium" }
−2.01 V. The ionization potential of a neutral berkelium atom is 6.23 eV. === Allotropes === At ambient conditions, berkelium assumes its most stable α form which has a hexagonal symmetry, space group P63/mmc, lattice parameters of 341 pm and 1107 pm. The crystal has a double-hexagonal close packing structure with the ...	{ "page_id": 3758, "title": "Berkelium" }
lanthanum(III) chloride-strontium chloride melts. A similar behavior is observed for the lanthanide analogue of berkelium, terbium. Aqueous solutions of Bk3+ ions are green in most acids. The color of Bk4+ ions is yellow in hydrochloric acid and orange-yellow in sulfuric acid. Berkelium does not react rapidly with oxyg...	{ "page_id": 3758, "title": "Berkelium" }
at the testing site of the first United States' first thermonuclear weapon, Ivy Mike, (1 November 1952, Enewetak Atoll), revealed high concentrations of various actinides, including berkelium. For reasons of military secrecy, this result was not published until 1956. Nuclear reactors produce mostly, among the berkelium...	{ "page_id": 3758, "title": "Berkelium" }
the name berkelium (symbol Bk) after the city of Berkeley in a manner similar to that used in naming its chemical homologue terbium (atomic number 65) whose name was derived from the town of Ytterby, Sweden, where the rare earth minerals were first found." This tradition ended with berkelium, though, as the naming of t...	{ "page_id": 3758, "title": "Berkelium" }
out in the presence of a citric acid/ammonium buffer solution in a weakly acidic medium (pH ≈ 3.5), using ion exchange at elevated temperature. The chromatographic separation behavior was unknown for element 97 at the time but was anticipated by analogy with terbium. The first results were disappointing because no alph...	{ "page_id": 3758, "title": "Berkelium" }
n , γ ) Cm 96 249 {\displaystyle {\begin{aligned}{\ce {^{239}_{94}Pu ->[{\ce {4(n,\gamma)}}] ^{243}_{94}Pu ->[\beta^-][4.956 \ {\ce {h}}] ^{243}_{95}Am ->[{\ce {(n,\gamma)}}] ^{244}_{95}Am ->[\beta^-][10.1 \ {\ce {h}}]}}&{\ce {^{244}_{96}Cm}}\\&{\ce {^{244}_{96}Cm ->[{\ce {5(n,\gamma)}}] ^{249}_{96}Cm}}\end{aligned}}} ...	{ "page_id": 3758, "title": "Berkelium" }
248Cf which had been previously characterized. The half-life of 248Bk was estimated as 23±5 hours, though later 1965 work gave a half-life in excess of 300 years (which may be due to an isomeric state). Berkelium-247 was produced during the same year by irradiating 244Cm with alpha-particles: { Cm 96 244 → ( α , n ) Cf...	{ "page_id": 3758, "title": "Berkelium" }
more complex separation procedure. Various inorganic oxidation agents can be applied to the berkelium(III) solution to convert it to the +4 state, such as bromates (BrO−3), bismuthates (BiO−3), chromates (CrO2−4 and Cr2O2−7), silver(I) thiolate (Ag2S2O8), lead(IV) oxide (PbO2), ozone (O3), or photochemical oxidation pr...	{ "page_id": 3758, "title": "Berkelium" }
This irradiation method was and still is the only way of producing weighable amounts of the element, and most solid-state studies of berkelium have been conducted on microgram or submicrogram-sized samples. The world's major irradiation sources are the 85-megawatt High Flux Isotope Reactor at the Oak Ridge National Lab...	{ "page_id": 3758, "title": "Berkelium" }
H2 → Bk2O3 + H2O Upon heating to 1200 °C, the oxide Bk2O3 undergoes a phase change; it undergoes another phase change at 1750 °C. Such three-phase behavior is typical for the actinide sesquioxides. Berkelium(II) oxide, BkO, has been reported as a brittle gray solid but its exact chemical composition remains uncertain. ...	{ "page_id": 3758, "title": "Berkelium" }
important property of radioactive solids has been studied on these two crystal forms: the structure of fresh and aged 249BkBr3 samples was probed by X-ray diffraction over a period longer than 3 years, so that various fractions of berkelium-249 had beta decayed to californium-249. No change in structure was observed up...	{ "page_id": 3758, "title": "Berkelium" }
They are non-stoichiometric with the nominal formula BkH2+x (0 < x < 1). Several other salts of berkelium are known, including an oxysulfide (Bk2O2S), and hydrated nitrate (Bk(NO3)3·4H2O), chloride (BkCl3·6H2O), sulfate (Bk2(SO4)3·12H2O) and oxalate (Bk2(C2O4)3·4H2O). Thermal decomposition at about 600 °C in an argon a...	{ "page_id": 3758, "title": "Berkelium" }
Research (JINR), Dubna, Russia, after bombarding it with calcium ions in the U400 cyclotron for 150 days. This synthesis was a culmination of the Russia-US collaboration between JINR and Lawrence Livermore National Laboratory on the synthesis of elements 113 to 118 which was initiated in 1989. == Nuclear fuel cycle == ...	{ "page_id": 3758, "title": "Berkelium" }
harmless to humans as compared to other actinides. However, berkelium-249 transforms with a half-life of only 330 days to the strong alpha-emitter californium-249, which is rather dangerous and has to be handled in a glovebox in a dedicated laboratory. Most available berkelium toxicity data originate from research on a...	{ "page_id": 3758, "title": "Berkelium" }
Caterina Vitale (1566–1619) was the first female pharmacist and chemist in Malta, and the first female pharmacist of the Knights Hospitaller. Caterina Vitale was originally from Greece. She married Ettore Vitale, pharmacist of the Knights Hospitaller, when she was a teenager. Upon his death in 1590, she inherited his p...	{ "page_id": 52104883, "title": "Caterina Vitale" }
The molecular formula C36H44N4O8 (molar mass: 660.75 g/mol, exact mass: 660.315914 u) may refer to: Coproporphyrinogen I Coproporphyrinogen III	{ "page_id": 24121012, "title": "C36H44N4O8" }

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