Chromium Isotopes: Stable chromium atoms that have the same atomic number as the element chromium, but differ in atomic weight. Cr-50, 53, and 54 are stable chromium isotopes.Chromium: A trace element that plays a role in glucose metabolism. It has the atomic symbol Cr, atomic number 24, and atomic weight 52. According to the Fourth Annual Report on Carcinogens (NTP85-002,1985), chromium and some of its compounds have been listed as known carcinogens.Chromium Compounds: Inorganic compounds that contain chromium as an integral part of the molecule.Isotopes: Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)Isotope Labeling: Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.Chromates: Salts of chromic acid containing the CrO(2-)4 radical.Nitrogen Isotopes: Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.Oxygen Isotopes: Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.Carbon Isotopes: Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.Chromium Alloys: Specific alloys not less than 85% chromium and nickel or cobalt, with traces of either nickel or cobalt, molybdenum, and other substances. They are used in partial dentures, orthopedic implants, etc.Picolinic AcidsWeldingPotassium Dichromate: Chromic acid (H2Cr2O7), dipotassium salt. A compound having bright orange-red crystals and used in dyeing, staining, tanning leather, as bleach, oxidizer, depolarizer for dry cells, etc. Medically it has been used externally as an astringent, antiseptic, and caustic. When taken internally, it is a corrosive poison.Zinc Isotopes: Stable zinc atoms that have the same atomic number as the element zinc, but differ in atomic weight. Zn-66-68, and 70 are stable zinc isotopes.Carcinogens, Environmental: Carcinogenic substances that are found in the environment.Tanning: A process of preserving animal hides by chemical treatment (using vegetable tannins, metallic sulfates, and sulfurized phenol compounds, or syntans) to make them immune to bacterial attack, and subsequent treatments with fats and greases to make them pliable. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Sulfur Isotopes: Stable sulfur atoms that have the same atomic number as the element sulfur, but differ in atomic weight. S-33, 34, and 36 are stable sulfur isotopes.Iron Isotopes: Stable iron atoms that have the same atomic number as the element iron, but differ in atomic weight. Fe-54, 57, and 58 are stable iron isotopes.Chromium Radioisotopes: Unstable isotopes of chromium that decay or disintegrate emitting radiation. Cr atoms with atomic weights of 46-49, 51, 55, and 56 are radioactive chromium isotopes.Deuterium: Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.Electroplating: Coating with a metal or alloy by electrolysis.Spectrophotometry, Atomic: Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.Diphenylcarbazide: Used as an indicator in titrating iron and for the colorimetric determination of chromium and the detection of cadmium, mercury, magnesium, aldehydes, and emetine.Strontium Isotopes: Stable strontium atoms that have the same atomic number as the element strontium, but differ in the atomic weight. Sr-84, 86, 87, and 88 are the stable strontium isotopes.Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Metals, Heavy: Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)Nickel: A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.Earth (Planet): Planet that is the third in order from the sun. It is one of the four inner or terrestrial planets of the SOLAR SYSTEM.Ice Cover: A thick mass of ICE formed over large regions of land; RIVERS; LAKES; ponds; or SEAWATER.Evolution, Planetary: Creation and development of bodies within solar systems, includes study of early planetary geology.Exobiology: The interdisciplinary science that studies evolutionary biology, including the origin and evolution of the major elements required for life, their processing in the interstellar medium and in protostellar systems. This field also includes the study of chemical evolution and the subsequent interactions between evolving biota and planetary evolution as well as the field of biology that deals with the study of extraterrestrial life.Solar System: The group of celestial bodies, including the EARTH, orbiting around and gravitationally bound by the sun. It includes eight planets, one minor planet, and 34 natural satellites, more than 1,000 observed comets, and thousands of lesser bodies known as MINOR PLANETS (asteroids) and METEOROIDS. (From Academic American Encyclopedia, 1983)Atmosphere: The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)Geologic Sediments: A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)Cyanobacteria: A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Photosynthesis: The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)Synechocystis: A form-genus of unicellular CYANOBACTERIA in the order Chroococcales. None of the strains fix NITROGEN, there are no gas vacuoles, and sheath layers are never produced.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Metals, Rare Earth: A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust.Siberia: A region, north-central Asia, largely in Russia. It extends from the Ural Mountains to the Pacific Ocean and from the Arctic Ocean to central Kazakhstan and the borders of China and Mongolia.Dysprosium: Dysprosium. An element of the rare earth family that has the atomic symbol Dy, atomic number 66, and atomic weight 162.50. Dysprosium is a silvery metal used primarily in the form of various salts.Ytterbium: Ytterbium. An element of the rare earth family of metals. It has the atomic symbol Yb, atomic number 70, and atomic weight 173. Ytterbium has been used in lasers and as a portable x-ray source.Samarium: Samarium. An element of the rare earth family of metals. It has the atomic symbol Sm, atomic number 62, and atomic weight 150.36. The oxide is used in the control rods of some nuclear reactors.Scandium: Scandium. An element of the rare earth family of metals. It has the atomic symbol Sc, atomic number 21, and atomic weight 45.Silica Gel: A non-crystalline form of silicon oxide that has absorptive properties. It is commonly used as a desiccating agent and as a stationary phase for CHROMATOGRAPHY. The fully hydrated form of silica gel has distinct properties and is referred to as SILICIC ACID.Evolution, Chemical: Chemical and physical transformation of the biogenic elements from their nucleosynthesis in stars to their incorporation and subsequent modification in planetary bodies and terrestrial biochemistry. It includes the mechanism of incorporation of biogenic elements into complex molecules and molecular systems, leading up to the origin of life.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Oxygen Consumption: The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)Reactive Oxygen Species: Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.Daphnia: A diverse genus of minute freshwater CRUSTACEA, of the suborder CLADOCERA. They are a major food source for both young and adult freshwater fish.Pulicaria: A plant genus of the family ASTERACEAE. Members contain pulicanadienes and other cytotoxic SESQUITERPENES.Cladocera: A suborder of CRUSTACEA, order Diplostraca, comprising the water fleas. They are benthic filter feeders that consume PHYTOPLANKTON. The body is laterally compressed and enclosed in a bivalved carapace, from which the head extends.Tillandsia: A plant genus of the family BROMELIACEAE. Members contain 3-methoxy-5-hydroxyflavonols.
Granzymes are the essential downstream effector molecules for the control of primary virus infections by cytolytic leukocytes. (1/174)Analysis of perforin-deficient mice has identified the cytolytic pathway and perforin as the preeminent effector molecule in T cell-mediated control of virus infections. In this paper, we show that mice lacking both granzyme A (gzmA) and granzyme B (gzmB), which are, beside perforin, key constituents of cytolytic vesicles, are as incapable as are perforin-deficient mice of controlling primary infections by the natural mouse pathogen ectromelia, a poxvirus. Death of gzmAxgzmB double knockout mice occurred in a dose-dependent manner, despite the expression of functionally active perforin and the absence of an intrinsic defect to generate splenic cytolytic T cells. These results establish that both gzmA and gzmB are indispensable effector molecules acting in concert with perforin in granule exocytosis-mediated host defense against natural viral pathogens. (+info)
Combined hepatic vein, umbilicoportal vein, and superior mesenteric artery catheterization in portal hypertension: estimation of the portal fraction of total hepatic blood flow in cirrhotic patients. (2/174)Hemodynamic data were obtained in 13 cirrhotic patients with severe portal hypertension, undergoing combined hepatic vein, umbilicoportal vein, and superior mesenteric artery catheterization. The relative clearance of indocyanine green, the portohepatic gradient (difference between the free portal venous pressure and the free hepatic venous pressure), and the estimated hepatic blood flow were measured. The portal fraction (PF) of total hepatic blood flow was calculated in all patients using indicator dilution curves obtained from the portal bifurcation, a right hepatic vein, and when possible a left hepatic vein (six cases) after injection of (51)Cr-labeled red blood cells ((51)Cr RBC) into the superior mesenteric artery. Flows were overestimated because of loss of indicator through spontaneous portosystemic shunts; however, the ratio between hepatic and portal indicator dilution curves can be used to calculate the portal fraction of total hepatic blood flow since no extrahepatic shunts existed after the bifurcation of the portal vein (as shown on portography). In 10 patients, 15 series of curves were calculable and the PF varied between 30.1 and 100% (mean +/- SE: 71.1 +/- 6.2%). In the three other patients, only delayed activity from recirculation was detected from portal and hepatic vein samples and PF was 0%; in these three cases, portography and arteriography revealed spontaneous portacaval shunting with reverse and/or stagnant circulation in the portal vein. In the 13 patients, no correlation existed between PF and the relative clearance of indocyanine green or the portohepatic gradient, parameters generally used as indices of severity in cirrhosis. In 10 patients, no correlation was found between PF and the estimated hepatic blood flow.These data indicate that (51)Cr RBC dilution curves can be used for the estimation of the portal fraction of total hepatic blood flow in conscious cirrhotic patients before portacaval shunts. Using this methodology, it could be assessed whether any critical level of portal fraction exists above which poor clinical results occur after portacaval shunting. This measurement could eventually be helpful in determining the appropriate surgical procedure to be applied in individual cases. (+info)
Chromium isotopes and the fate of hexavalent chromium in the environment. (3/174)Measurements of chromium (Cr) stable-isotope fractionation in laboratory experiments and natural waters show that lighter isotopes reacted preferentially during Cr(VI) reduction by magnetite and sediments. The 53Cr/52Cr ratio of the product was 3.4 +/- 0.1 per mil less than that of the reactant. 53Cr/52Cr shifts in water samples indicate the extent of reduction, a critical process that renders toxic Cr(VI) in the environment immobile and less toxic. (+info)
The estimation of red cell volume with 51Cr-labelled erythrocytes and plasma volume with radioiodinated human serum albumin. (4/174)The validity of a simplified procedure for the direct estimation of both red cell and plasma volume, using (51)Cr-labelled erythrocytes and radioiodinated human serum albumin, has been examined. It is suggested that the procedure, involving three venepunctures only, will yield accurate measurements of both compartments. (+info)
DIAGNOSTIC VALUE OF SERUM HAPTOGLOBIN. (5/174)Serum haptoglobin has been estimated quantitatively in 25 patients with haemolytic disease, and its diagnostic value assessed by comparing the levels with those obtained in 110normal subjects, in 149 patients with other forms of anaemia, and in 37 patients with non-haematological disorders. The normal range was found to be 33 to 213 mg./100 ml.; subnormal levels were found in 80% of patients with haemolytic disease or megaloblastic anaemia, patients with haemorrhage into the tissues, and occasionally in association with other diseases. When taken in conjunction with other clinical and laboratory features this simple biochemical estimation can be of diagnostic value. (+info)
JAK3/STAT5/6 pathway alterations are associated with immune deviation in CD8 T cells in renal cell carcinoma patients. (6/174)(+info)
Differential isotopic fractionation during Cr(VI) reduction by an aquifer-derived bacterium under aerobic versus denitrifying conditions. (7/174)(+info)
NK cell-induced cytotoxicity is dependent on a Ca2+ increase in the target. (8/174)In previous work we showed that programmed cell death (PCD) in thymocytes is mediated by a sustained increase in cytosolic Ca2+ concentration, resulting in the activation of an endogenous endonuclease, DNA fragmentation, and cell death. In this study we investigated the roles of Ca2+ and DNA fragmentation in target cell killing by natural killer (NK) cells. The effector cells induced a rapid, sustained increase in cytosolic Ca2+ concentration in Jurkat target cells. Buffering the target cell cytosolic Ca2+ with the Ca2(+)-selective dye, quin-2, prevented target cell killing. Extensive DNA fragmentation was associated with killing in every target tested, and this response was also blocked by quin-2. The endonuclease inhibitor, aurintricarboxylic acid, inhibited both DNA fragmentation and killing without influencing the Ca2+ increase in target cells. Thus, it is concluded that NK cell killing depends on a Ca2+ increase and appears to involve endogenous endonuclease activation in target cells. (+info)
Great Oxygenation Event
"Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes". Nature. 461 (7261): 250-253. Bibcode: ... Chromium is not easily dissolved and its release from rocks would have required the presence of a powerful acid. One such acid ... Besides marine cyanobacteria, there is also evidence of cyanobacteria on land. A spike in chromium contained ... This change from MIF to MDF of sulfur isotopes also may have been caused by an increase in glacial weathering, or the ...
Geological history of oxygen
"Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes". Nature. 461 (7261): 250-253. Bibcode: ...
Computer components contain many toxic substances, like dioxins, polychlorinated biphenyls (PCBs), cadmium, chromium, ... radioactive isotopes and mercury. A typical computer monitor may contain more than 6% lead by weight, much of which is in the ...
Natural calcium is a mixture of five stable isotopes (40Ca, 42Ca, 43Ca, 44Ca, and 46Ca) and one isotope with a half-life so ... It is also used as a reducing agent in the production of chromium, zirconium, thorium, and uranium. It can also be used to ... Calcium isotope fractionation during mineral formation has led to several applications of calcium isotopes. In particular, the ... Mass-dependent differences in calcium isotope composition are conventionally expressed by the ratio of two isotopes (usually ...
Applied Radiation and Isotopes. 65, p9-16 Pitre,J. , Bédard, M. , Hineman, A. 2011. Quick and Easy Dissolution of Chromite Ores ... Ferrochromes, and Chromium Slags for ICP-OES without using HF or HClO4. Spectrocopy Online, May 1, 2014. Volume 29, Issue 5.. ... Determination of platinum, palladium, ruthenium and iridium in geological samples by isotope dilution inductively coupled ...
... chromium) isotopes. The chemistry of vanadium is noteworthy for the accessibility of the four adjacent oxidation states 2-5. In ... At least four isotopes have metastable excited states. Electron capture is the main decay mode for isotopes lighter than 51V. ... Naturally occurring vanadium is composed of one stable isotope, 51V, and one radioactive isotope, 50V. The latter has a half- ... The most stable of these isotopes are 49V with a half-life of 330 days, and 48V with a half-life of 16.0 days. The remaining ...
Bunburra Rockhole (meteorite)
The oxygen and chromium isotope results from Bunburra Rockhole are quite different to the bulk of the HED meteorite clan. ... The differences in oxygen and chromium isotopes and variable trace element compositions relative to the bulk HED measurements ... Oxygen Isotope analyses have contributed to the classification of meteorites and identification of potential origins. Typically ... Wiechert, U. H.; Halliday, A. N.; Palme, H.; Rumble, D. (2004-04-30). "Oxygen isotope evidence for rapid mixing of the HED ...
... isotopic contents are typically combined with chromium isotopic contents and have found application in isotope ... "Manganese". Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Chromium, Iodine, Iron, Manganese, ... All of the remaining radioactive isotopes have half-lives of less than three hours, and the majority of less than one minute. ... The primary decay mode before the most abundant stable isotope, 55Mn, is electron capture and the primary mode after is beta ...
... that the impact hypothesis is further supported by chromium isotope evidence for the presence of extraterrestrial material. The ... Extraterrestrial Chromium at the Graphite Peak P/Tr boundary and in the Bedout Impact Melt Breccia. Lunar and Planetary Science ...
As the neutron energy increases, the neutron cross section of most isotopes decreases. The boron isotope 10B is responsible for ... They can be made out of stainless steel or other neutron window materials such as zirconium, chromium, silicon carbide or cubic ... They may be reduced by capturing long isotope rows of the same element or by not using neutron absorbers for trimming. For ... over metastable conditions like for isotope 235mU, which offers a half time of about 26 min. Other means of controlling ...
The level of chromium isotope 54Cr in Österplana 065 is similar to those in ordinary chondrites, while oxygen isotopes are ... Österplana 065 also features a chromium-spinel-rutile assemblage, not observed in other meteorites. Österplana 065 is believed ...
By studying the chromium isotope composition in ancient ironstones, measuring the ratio of heavier 53Cr (which is more ... By tracing the movement of chromium isotopes from land to ocean, a process that is sensitive to atmospheric oxygen levels, the ... Small amounts of oxygen can convert insoluble chromium, a constituent of the continental crust to a soluble form which is then ... The Lomagundi Excursion Event is considered to be the most prominent carbon isotope event in Earth's history and can provide ...
The proton-rich isotopes from 258Sg to 261Sg were directly produced by cold fusion; all heavier isotopes were produced from the ... They readily portray their group oxidation state of +6, although this is highly oxidising in the case of chromium, and this ... All the remaining isotopes have half-lives measured in milliseconds, with the exception of the shortest-lived isotope, 261mSg, ... There is a trend toward increasing half-lives for the heavier isotopes; thus the heaviest three known isotopes, 267Sg, 269Sg, ...
Hydraulic fracturing and radionuclides
Its most stable isotope, Radon-222, has a half-life of 3.8 days. Strontium is also naturally occurring and may be dislodged by ... Chromium-51, Cobalt-57, Cobalt-58, Cobalt-60, Gold-198, Iodine-127, Iodine-128, Iodine-129, Iodine-130, Iron-59, Krypton-85, ... Radium (Ra) is a product of Uranium-238 decay, and is the longest-lived isotope of radium with a half-life of 1601 years; next ... Other gamma-emitting tracer isotopes used are Antimony-121, Antimony-122, Antimony-123, Antimony-125, Antimony-126, Antimony- ...
All isotopes of this element are radioactive with half lives of 17.7 years or less. The promethium in the outer envelope may be ... This is classified as an Ap/Bp star, with a peculiar spectrum showing lines of chromium and europium that change in intensity ...
... to nucleosynthesis neutron capture and the Chart of the nuclides the chart of the Nuclides Discovery of the Chromium isotopes, ... This activated isotope is used in oil drilling to determine the clay content (clay is generally an alumino-silicate) of the ... An example of this kind of fission in a light element can occur when the stable isotope of lithium, lithium-7, is bombarded ... For example, one of the fairly unique isotopes found in trinitite, and therefore with its absence likely signifying a fake ...
... in Darmstadt bombarded a target of bismuth-209 with accelerated nuclei of chromium-54 to produce 5 atoms of the isotope bohrium ... Although the heavy isotope 274Bh requires a rare and highly radioactive berkelium target for its product, the isotopes 272Bh, ... Bohrium has no stable or naturally occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory, ... and the even heavier unconfirmed isotope 278Bh appearing to have an even longer half-life of about 690 s. The unknown isotopes ...
Heavier isotopes are expected to be more stable; 320Ubu is predicted to be the most stable unbiunium isotope, but there is no ... chromium-54, iron-58, or nickel-64. This however has the drawback of resulting in more symmetrical fusion reactions that are ... This would present a grave problem for experiments aiming at synthesising isotopes of unbiunium if true, because the isotopes ... the only stable isotope of aluminium has 13 protons and 14 neutrons, making a neutron-proton ratio of 1.077). However, isotopes ...
Cyanobacteria - Simple English Wikipedia, the free encyclopedia
Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes. Nature 461 (7261): 250-253. Abstract:  ...
Isotopes of bohrium
In 2007, the team at LBNL studied the analogous reaction with chromium-52 projectiles for the first time to search for the ... The first isotope to be synthesized was 262Bh in 1981. There are 11 known isotopes ranging from 260Bh to 274Bh, and 1 isomer, ... The longest-lived isotope is 270Bh with a half-life of 1 minute, although the unconfirmed 278Bh may have an even longer half- ... Isotope masses from: M. Wang; G. Audi; A. H. Wapstra; F. G. Kondev; M. MacCormick; X. Xu; et al. (2012). "The AME2012 atomic ...
Isotopes of manganese
Manganese isotopic contents are typically combined with chromium isotopic contents and have found application in isotope ... The isotopes of manganese range in atomic weight from 46 u (46Mn) to 65 u (65Mn). The primary decay mode before the most ... Registration required (help)). Isotope masses from: G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The ... All of the remaining radioactive isotopes have half-lives that are less than 3 hours and the majority of these have half-lives ...
Isotopes of vanadium
... chromium) isotopes. Bold for isotopes with half-lives longer than the age of the universe (nearly stable) Abbreviations: EC: ... Naturally occurring vanadium (23V) is composed of one stable isotope 51V and one radioactive isotope 50V with a half-life of ... with all of the isotopes lighter than it, and none of the heavier, have unknown half-lives. In 4 isotopes, metastable excited ... Registration required (help)). Isotope masses from: G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The ...
Canyon Diablo (meteorite)
The troilite in this sample is used as the standard reference for sulfur isotope ratios. Moissanite - a variety of silicon ... Minerals reported from the meteorite include: Cohenite - iron carbide Chromite - iron magnesium chromium oxide Daubréelite - ... In 1953, Clair Cameron Patterson measured ratios of the lead isotopes in samples of the meteorite. The result permitted a ... iron(II) chromium sulfide Diamond and lonsdaleite - carbon Graphite - carbon Haxonite - iron nickel carbide Kamacite iron ...
Isotopes of chromium
The isotopes of chromium range from 42Cr to 67Cr. The primary decay mode before the most abundant stable isotope, 52Cr, is ... ISBN 978-0-8493-0485-9. Chromium isotopes data from The Berkeley Laboratory Isotopes Project's. ... Naturally occurring chromium (24Cr) is composed of four stable isotopes; 50Cr, 52Cr, 53Cr, and 54Cr with 52Cr being the most ... Chromium isotopic contents are typically combined with manganese isotopic contents and have found application in isotope ...
Hf/W isotopes derived from the martian meteorite Zagami, indicate rapid accretion and core differentiation of Mars; i.e. under ... The core contains half the Earth's vanadium and chromium, and may contain considerable niobium and tantalum. The core is ... Earth's core contains half the Earth's vanadium and chromium, and may contain considerable niobium and tantalum. Earth's core ...
Extinct isotopes of superheavy elements
This is later called into question as iron chromium sulfide is very rare with a relative abundance of 0.4%. By the 1980s, CCF ... Extinct isotopes of superheavy elements are isotopes of elements whose half-lives were too short to have lasted through the ... Carbonaceous chondrite fission Xe, often abbreviated as CCF Xe, are a collection of different isotopes of xenon that were ... Lewis, R. S.; Anders, E.; Shimamura, T.; Lugmair, G. W. (1983-01-01). "Barium Isotopes in Allende Meteorite: Evidence against ...
Group 3 element
Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton ... Flerov, G. N. (1967). "On the nuclear properties of the isotopes 256103 and 257103". Nucl. Phys. A. 106 (2): 476. Bibcode: ... For comparison, the abundance of copper is 50 ppm, that of chromium is 160 ppm, and that of molybdenum is 1.5 ppm. ... The first atoms of lawrencium were produced by bombarding a three-milligram target consisting of three isotopes of the element ...
Kromium bahasa Indonesia, ensiklopedia bebas
"Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes". Nature. 461 (7261): 250-253. Bibcode: ... Chromium. IN: Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Chromium, Iodine, Iron, Manganese, ... "Chromium". Diakses tanggal 2008-08-24.. *^ a b c Dennis, J. K.; Such, T. E. (1993). "History of Chromium Plating". Nickel and ... Inggris) Chromium at The Periodic Table of Videos (University of Nottingham). *(Inggris) "Chromium". Encyclopædia Britannica. 6 ...
'Smart' Dressing Provides Doctors Warning of Wound Infections - Legacy MedSearch | Medical Device...
As the famous writer, philosopher and politician, Benjamin Franklin (the guy on the $100 bill) once said, "An ounce of prevention is worth a pound of cure." A team of British scientists took it upon themselves to develop a smart wound dressing that changes color when it comes into contact with certain bacteria. In a wound, bacteria from the surrounding skin and other sources quickly find their way in and start to multiply forming colonies. This is absolutely normal, but there are some cases where the bacterial load reaches a critical point, at which immune clearance is no longer effective. Its at this point that medical intervention becomes a must, so Ben Franklin hit the nail right on the head.. ...
We first showed that human FGF19 was stable in mouse blood and its half-time disappearance was further extended by excess FGF19. In the "hot only" group, there was no meaningful permeation of 125I-FGF19 into brain as seen by multiple-time regression analysis. The initial volume of distribution of 125I-FGF19 remained higher than that of co-administered 131I-albumin. The presence of FGF19 in the cerebral vasculature may allow its binding and activation of BBB endothelia and thus induce CNS function indirectly without crossing the BBB, as seen with adiponectin . Nevertheless, the small portion of FGF19 entering the brain was stable for at least 10 min, so that it could exert direct CNS effects.. The influx of 125I-FGF19 became significant in the presence of excess unlabeled FGF19 or its homolog FGF15 both by multiple-time regression analysis after iv injection and by in-situ brain perfusion. Because of the low level of permeation without an increase of Vi over time, we did not perform capillary ...
Looking for online definition of cytolipin Hcytolipin K in the Medical Dictionary? cytolipin Hcytolipin K explanation free. What is cytolipin Hcytolipin K? Meaning of cytolipin Hcytolipin K medical term. What does cytolipin Hcytolipin K mean?
Oncolytic viruses are a concept Id like to be more excited by than I am.2 Its an idea that seemed really exciting when I first came across it, but the more I thought about it the more dubious I was. But a recent paper helps me feel better about at least two of my worries.. The concept is a straightforward one. Viruses are good at killing cells.3 Why not have them infect cells that we want to die? That would be, for example, cancer cells. So all you need to do is find or make a virus that only grows in cancer cells, and youre cured. Simple! Tomorrow well fix global warming!. Theres the obvious problem with this: How can you find (or make) a cancer-specific virus? In principle the answer is the same as with chemotherapy; you use the ways cancer cells are different from normal as targets. This isnt as hard as you might think. Lots of the things that make cancer cells cancerous are similar to the things viruses like. Viruses often drive infected cells into a cancer-like state that is more ...
Applying biological molecules from cell membranes to the surfaces of artificial materials is opening peepholes on the very basics of cell-to-cell interaction.
In Actinomycin-behandelten Mäusen nahm die Zahl der zirkulierenden Erythrozyten linear ab. Zellulärer Hämoglobinverlust erklärt die scheinbar altersunabhängige Komponente der Erythrozytendestruktion...
Organs:, Serology: Antigen,, Congenic Resistant Lines: B10.A, B10.BR, B10.D2/O, B10.M, Genes: H-2 - Histocompatibility-2, Strains: C3H, H-2G (HTG). ...
Functional dissection of phagocytosis in Nervous system development and the immune system of Drosophila melanogaster
Phagocytes remove apoptotic cells during development and eliminate pathogens in the immune system. The underlying molecular and cellular mechanisms, particularly the differences between macrophages and non-professional phagocytes like glia, are not well understood. We used novel cell-based assays to screen phagocytic function of candidate genes assembled from literature and our genome-wide transcription profiling of Drosophila melanogaster embryonic glia. Gene function was knocked-down by RNAi and phagocytic efficiency assessed by flow cytometry; to explore functional specificity, we offered not only bacteria, but also apoptotic cells and beads as food. To validate results in vivo, we analysed glial clearance of apoptotic neurons in embryonic development and immune clearance of bacteria in adult flies using both genetic mutants and transgenic RNAi. Our screen provides a cross section of the different steps of phagocytosis from recognition to engulfment and phagosomal degradation. For the ...
Most protozoa survive environmental stress by encapsulating to form a cyst or spore. This process is medically important because cysts of pathogenic protists are resistant to immune clearance, antibiotics and biocides. In addition, cysts of bacterivorous protists such as Acanthamoeba castellani are exploited act as vectors for survival and airborne dispersal by bacterial pathogens, such as Legionella pneumoniae and MRSA. Due to the limited genetic tractability of encysting organisms, the mechanisms controlling encystation are largely unknown.. Dictyostelid social amoebas survive stress by building fruiting structures with encapsulated spores and stalk cells. Both cell types mature in response to cAMP activation of PKA. We showed earlier that this process is evolutionary derived from encystation in solitary amoebas, which we found to also require cAMP acting on PKA. The encysting Dictyostelid Polysphondylium pallidum is uniquely suitable for both reverse and forward genetic approaches, which ...
Many bacterial infections involve biofilm formation. Cells within a biofilm are significantly more resistant to immune clearance and antibiotics compared to unattached, planktonic cells. Berk et al. (p. 236) applied superresolution optical methods to image living bacteria with nanometer-scale precision as they form a biofilm. Vibrio cholerae biofilms were observed to have three distinct levels of spatial organization: cells, clusters of cells, and collections of clusters. Each cell cluster was wrapped in a flexible, elastic envelope. Several V. cholerae matrix proteins played complementary architectural roles during biofilm development. RbmA provided cell-cell adhesion, Bap1 allowed the developing biofilm to adhere to surfaces, and heterogeneous mixtures of VPS, RbmC, and Bap1 formed the dynamic, flexible, and ordered envelopes that encase the cell clusters. ...
"Murine t cell-specific ia antigens: monoclonal antibodies define an i-" by C E. Hayes and D A. Hullett
Hybridoma:, Neoplasm:, Serology: Antigen, Types of Tumors:, Congenic Resistant Lines: B10.A (5R), B10.A (4R), A.TL, B10.HTT, A.TH, B10.MBR, Genes: H-2 - Histocompatibility-2, Strains: A(CAL-A) (A/J), BALB/C, CBA, C57BL/6. ...
Provides fundamental knowledge of cell-to-cell interactions necessary for proper development and organization of the nervous system. Topics include pattern formation, neuronal differentiation, axon guidance, and target interactions. Prerequisite: Permission of the Instructor. Alternate years ...
51Cr radionuclide EDTA. Ussed to measure glomerular filtration rates, in chromium-51-EDTA plasma clearance studies, and in intestinal permeability studies
Chromium-51 Radionuclide, 5mCi (185MBq), Sodium Chromate in Normal Saline (pH 8-10), Steri-packaged | PerkinElmer
Chromium-51 is the most commonly used readioactive marker for the labeling of target cells in cytotoxicity assays. The common name for such assays Chromium Release also describes the fundamental method behind the assay procedure. Methods for the precise and accurate quantification of cytotoxicity are of fundamental importance in immunology particularly for the study of tumor and virus cytolysis ...
Cytotoxicity to allogeneic cells in the chicken. I. Role of macrophages in the cytotoxic effect on 51Cr-labeled red blood cells...
Semantic Scholar extracted view of Cytotoxicity to allogeneic cells in the chicken. I. Role of macrophages in the cytotoxic effect on 51Cr-labeled red blood cells by immune spleen cells. by Melissa A Palladino et al.
when solid aluminum is heated with chromium(II) oxide, solid chromium and aluminum oxide are produced. If you are using 125 g of aluminum and 225 g of chromium (II) oxide, how many grams of chromium are produced. If you actually collect ...
Thank you for your interest in spreading the word about Clinical Science.. NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.. ...
A method for the determination of red cell mass, which employs the use of radioisotopically-labeled erythrocytes, in the embryonated hen egg is described and results of total blood volume, plasma volume, red cell mass and red cell concentration determinations during the period from 9 to 18 days of incubation presented. Considerations of the values obtained in terms of absolute quantities and relative to embryonic mass are discussed. It is suggested that expansion of the red cell mass and somatic growth are portions of a common process and may be subject to a complex of similar regulatory factors in the normal chick embryo.. ...
"The role of BST-2/Tetherin in host protection and disease manifestatio" by Wadie D. Mahauad-Fernandez and Chioma M. Okeoma
Host cells respond to viral infections by activating immune response genes that are not only involved in inflammation, but may also predispose cells to cancerous transformation. One such gene is BST-2, a type II transmembrane protein with a unique topology that endows it tethering and signaling potential. Through this ability to tether and signal, BST-2 regulates host response to viral infection either by inhibiting release of nascent viral particles or in some models inhibiting viral dissemination. However, despite its antiviral functions, BST-2 is involved in disease manifestation, a function linked to the ability of BST-2 to promote cell-to-cell interaction. Therefore, modulating BST-2 expression and/or activity has the potential to influence course of disease.
If your institution subscribes to this resource, and you dont have a MyAccess Profile, please contact your librarys reference desk for information on how to gain access to this resource from off-campus. OK ...
... is prescribed to relieve symptoms and reduce spleen size in people with myelofibrosis. This eMedTV article gives an overview of this medicine, including how it works, details on its effectiveness, possible side effects, and more.
In conclusion, the concept of the erythron is discussed as a logical way to approach the physiology of erythropoiesis and as a basis for understanding the pathophysiological disturbances whIch characterise the red cell abnormalities. Using this approach, both increase in red cell mass, or erythrocytosis, and decrease in red cell mass, or anaemia, are seen simply as manifestations of a disturbance in the normal regulatory mechanisms of the erythron.
Learn more about Chromium uses, effectiveness, possible side effects, interactions, dosage, user ratings and products that contain Chromium
Please fill out the form below with all the relevant details. If want to request information on more than one illustration, you may prefer to e-mail me directly instead. If you do, please include the link to this illustration and the other illustrations: http://www.karitoverud.com/illustrations/C/28/. ...
Product Page for Chromium Polynicotinate ChromeMate 200mcg 100 Caps made by olympian-labs offering price, ingredients and full item description from betterlife
ഫലകം:Infobox scandium - വിക്കിപീഡിയ
Chromium,Chromium [[Manganese,Manganese [[Iron,Iron [[Cobalt,Cobalt [[Nickel,Nickel [[Copper,Copper [[Zinc,Zinc [[Gallium, ... Iso-tope Abun-dance Half-life (t1/2) Decay mode Pro-duct ...https://ml.wikipedia.org/wiki/%E0%B4%AB%E0%B4%B2%E0%B4%95%E0%B4%82:Infobox_scandium
Isotopes of chromium - Wikipedia
The isotopes of chromium range from 42Cr to 67Cr. The primary decay mode before the most abundant stable isotope, 52Cr, is ... ISBN 978-0-8493-0485-9. Chromium isotopes data from The Berkeley Laboratory Isotopes Projects. ... Naturally occurring chromium (24Cr) is composed of four stable isotopes; 50Cr, 52Cr, 53Cr, and 54Cr with 52Cr being the most ... Chromium isotopic contents are typically combined with manganese isotopic contents and have found application in isotope ...https://en.wikipedia.org/wiki/Isotopes_of_chromium
GSA Today - The case for a Neoproterozoic Oxygenation Event: Geochemical evidence and biological consequences
Chromium Isotopes. This new method may be the only one capable of tracing increases in atmospheric oxygen, because chromium ... comm.). (H) Key aspects of the Precambrian history of hexavalent chromium in sea water. Increasing Cr isotope fractionation (δ ... Sulfur Isotopes. Sulfur isotope discrimination (marine sulfate δ34S − pyrite sulfide δ34S) increased to modern values during ... Carbon Isotopes. The carbon isotope record provides insight into the Neoproterozoic global carbon cycle. Since the pioneering ...http://geosociety.org/gsatoday/archive/21/3/article/i1052-5173-21-3-4.htm
Chromium - New World Encyclopedia
Chromium compounds of oxidation state +6 are powerful oxidants.. Isotopes. The isotopes of chromium range in atomic weight from ... Chromium metal and chromium(III) compounds are not usually considered health hazards, but hexavalent chromium (chromium VI) ... Chromium(III) oxide. Chromium(III) oxide (Cr2O3) also known as chromium sesquioxide or chromia, is one of four oxides of ... The human body needs trace amounts of trivalent chromium (chromium(III)) for sugar metabolism, but hexavalent chromium ( ...http://www.newworldencyclopedia.org/entry/Chromium
Researchers discover heaviest known calcium atom; eight new rare isotopes discovered in total
Researchers from Michigan State University and the RIKEN Nishina Center in Japan discovered eight new rare isotopes of the ... which may be the heaviest calcium isotopes. Explore further: ISOLDE mints isotopes of chromium ... ISOLDE mints isotopes of chromium. July 6, 2018 CERNs nuclear physics facility, ISOLDE, has minted a new coin in its ... The facility has forged neutron-rich isotopes of the element chromium for the first time, and in prodigious quantities. ... ...https://phys.org/news/2018-07-heaviest-calcium-atom-rare-isotopes.html
Discovery Metadata Dataset:The oxygen fugacity of core segregation and the redox evolution of the mantle: constraints from iron...
Implications for fractionation during core formation Unlocking the zinc isotope systematics of iron meteorites Iron isotope ... Four papers are linked to this grant: Stable chromium isotopic composition of meteorites and metal-silicate experiments: ... CHROMIUM ISOTOPES EARTH CORE EARTH MANTLE IRON METEORITES ISOTOPES METEORITES OXIDATION PERIDOTITE PEROVSKITE PYROXENITE ... The oxygen fugacity of core segregation and the redox evolution of the mantle: constraints from iron and chromium isotopes ( ...http://www.bgs.ac.uk/discoverymetadata/13606881.html
Find BGS datasets by browsing an A to Z list of keywords
Chromium (11). Chromium isotopes (1). Clay minerals (1). Climate change (14). Climatology (14) ...https://www.bgs.ac.uk/discoverymetadata/keywords.html
Great Oxygenation Event - Wikipedia
"Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes". Nature. 461 (7261): 250-253. Bibcode: ... Chromium is not easily dissolved and its release from rocks would have required the presence of a powerful acid. One such acid ... Besides marine cyanobacteria, there is also evidence of cyanobacteria on land. A spike in chromium contained ... This change from MIF to MDF of sulfur isotopes also may have been caused by an increase in glacial weathering, or the ...https://en.wikipedia.org/wiki/Great_Oxygenation_Event
UNdata | record view | Trade of goods , US$, HS 1992, 28 Inorganic chemicals, precious metal compound, isotope
Chromium trioxide. Chromium oxides, hydroxides except chromium trioxide. Manganese dioxide. Manganese oxides other than ... Chromium sulphates. Nickel sulphates. Copper sulphates. Zinc sulphate. Barium sulphate. Sulphates of metals nes. Alums. ... Isotopes nes, compounds. Cerium compounds. Compounds, mixes of rare-earths, yttrium, scandium ne. Hydrogen peroxide. Phosphides ... Trade of goods , US$, HS 1992, 28 Inorganic chemicals, precious metal compound, isotope. Search glossaries. Source: Commodity ...http://data.un.org/Data.aspx?q=inorganic+chemicals&d=ComTrade&f=_l1Code%3A29%3Byr%3A2017%3BcmdCode%3A281121&c=2,3,4,5,7,8,9,11,12&s=_crEngNameOrderBy:asc,yr:desc,_l2Code:asc&v=1
Chromium: The mineralogy of Chromium
Main isotopes of Chromium. Isotope. % in Nature. Half Life. Decay type. Decay product. ... Most widespread minerals containing Chromium. This list of minerals containing Chromium is built from the mindat.org locality ... Element association of Chromium in the Mineral World. This table compares the known valid mineral species listed listed with ... chromium (III) nitrate nonahydrate. [Cr(H2O)6](NO3)3 · 3H2O. +3. ...https://www.mindat.org/element/Chromium
Oxy-Anion Stable Isotope Consortium
Chromium reduction sulfur line for extracting pyrite and acid-volatile sulfur; Soxhlet extraction apparatus for extracting ... OASIC currently has two isotope ratio mass spectrometers (MAT253 and Isoprime 100) and one laser absorption isotopic water ...http://www.lsu.edu/science/geology/research_areas/oasic/facility.php
Proterozoic oxygen rise linked to shifting balance between seafloor and terrestrial weathering | PNAS
2009) Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes. Nature 461(7261):250-253. ... 1992) Carbon isotope evidence for the stepwise oxidation of the Proterozoic environment. Nature 359(6396):605-609. ... An alternative isotope model incorporates seafloor weathering as a carbon removal pathway (28) and produces similar forg ... S6), our predicted forg fits the isotope model (8) more closely. However, the present work is primarily concerned with the ...https://www.pnas.org/content/111/25/9073
CiNii Articles - MIZUMACHI KUNIHIKO
Isotopes in Extraterrestrial Materials （1963） * Isotopic Measurement of Chromium Induced by Cosmic Rays in Iron Meteorites. （ ...https://ci.nii.ac.jp/author?q=MIZUMACHI+KUNIHIKO
Isotope Stock Footage and Videos. 131 Isotope royalty free video and movie clips available to search from hundreds of buyout...
Over 131 Isotope pictures to choose from, with no signup needed. Download in under 30 seconds. ... Chromium atom, with elements symbol, number, mass and element type color. Stock Videosby oneo20/21. Samarium atom, with ...https://www.canstockphoto.com/footage-video/isotope.html
Table of Contents - March 18, 2011, 331 (6023) | Science
The different chromium isotopic compositions of chondrites and the mantle offer insight into Earths early history. ...http://science.sciencemag.org/content/331/6023
Aluminum Molybdenum Vanadium Chromium Titanium Alloy | AMERICAN ELEMENTS ®
Aluminum Molybdenum Vanadium Chromium Titanium Alloy Al-Mo-V-Cr-Ti bulk & research qty manufacturer. Properties, SDS, ... Titanium has five naturally occurring isotopes: 46Ti through 50Ti, with 48Ti being the most abundant (73.8%). Titanium is found ... 24 Cr 51.996100000 Chromium See more Chromium products. Chromium (atomic symbol: Cr, atomic number: 24) is a Block D, Group 6, ... The chromium atom has a radius of 128 pm and a Van der Waals radius of 189 pm. In its elemental form, chromium has a lustrous ...https://www.americanelements.com/aluminum-molybdenum-vanadium-chromium-titanium-alloy
CFR - Code of Federal Regulations Title 21
Isotope Chemical form Use Chromium 51. Chromate. Spleen scans. Do. ......do. Placenta localization. ... naturally occurring isotopes, or nonradioactive substances used in conjunction with isotopes. ... d)(1) In view of the extent of experience with the isotopes listed in paragraph (c) of this section, the Nuclear Regulatory ... 2) In view of the extent of experience with the isotopes listed in paragraph (f)(1) of this section, the Nuclear Regulatory ...https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?cfrpart=310&showfr=1
Table of Contents - October 23, 2018, 115 (43) | PNAS
Volatile loss following cooling and accretion of the Moon revealed by chromium isotopes Paolo A. Sossi, Frédéric Moynier, and ...https://www.pnas.org/content/115/43
Reinhard C[au] - PubMed - NCBI
Redox-independent chromium isotope fractionation induced by ligand-promoted dissolution.. Saad EM, Wang X, Planavsky NJ, ... Tracking the rise of eukaryotes to ecological dominance with zinc isotopes.. Isson TT, Love GD, Dupont CL, Reinhard CT, ...https://www.ncbi.nlm.nih.gov/pubmed?cmd=search&term=Reinhard+C%5Bau%5D&dispmax=50
Radioactive Isotopes in Industry - Radiation Alert® by S.E. International, Inc.
Chromium-51. Used in research in red blood cell survival studies. Used as a tracer in studies on blood. Used to study the flow ... Radioactive Isotopes in Industry. Posted on September 7, 2018. September 7, 2018. ...https://seintl.com/isotopes-in-industry/
Metals - ASTM International
MNL11869D: Evaluations of the Elevated Temperature Tensilde and Creep-Rupture Properties of 12 to 27 Percent Chromium Steels - ... MONO10021M: Chapter 6-Hydrogen Isotope Effects - 01 January 2001. MONO10022M: Chapter 7-Joining - 01 January 2001 ... MNL11863D: Evaluation of the Elevated Temperature Tensile and Creep-Rupture Properties of 3 to 9 Percent Chromium-Molybdenum ... MNL11917D: Supplemental Report on the Elevated-Temperature Properties of Chromium-Molybdenum Steels - 01 March 1971 ...https://www.astm.org/industry/metals-mnls.html
Cyanobacteria - Simple English Wikipedia, the free encyclopedia
Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes. Nature 461 (7261): 250-253. Abstract:  ...https://simple.wikipedia.org/wiki/Cyanobacteria
HexavalentStable isotopeSpeciated isotope dilution mass spectrometryTrivalent chromiumNeutronsElementalSystematicsHydrogen isotopeEvidence that taking cSmall amounts of chromiumOXIDATIONAtomsRatio27.7 daysAlloysForm of chromiumForms of chromiumIntake of chromiumPresence of chromium52CrTrioxideIRON METEORITESBrewer's yeastChloridePeriodic tableStrontiumIonsToxicPotassiumToxicityDepositsFractionationDeficiencyDecayAtomic number 24CarbonPicolinateChromite oreAbundantZincRubidiumDietaryAmountsResearchersDiffusionChemistry
- The human body needs trace amounts of trivalent chromium (chromium(III)) for sugar metabolism , but hexavalent chromium (chromium(VI)) is very toxic. (newworldencyclopedia.org)
- There are two forms of chromium: trivalent chromium and hexavalent chromium. (webmd.com)
- It is an essential dietary trace element, but hexavalent chromium is carcinogenic. (thefreedictionary.com)
- Hexavalent chromium is the highest oxidation state of elemental chromium. (drugs.com)
- Last year, water quality officials in North Carolina detected potentially harmful levels of hexavalent chromium, a carcinogen, in drinking-water wells near coal plants in the state. (phys.org)
- But scientists report in Environmental Science & Technology Letters that well water both near and far from the ponds in the state contains hexavalent chromium from natural sources. (phys.org)
- Hexavalent chromium, or Cr(VI), which the movie Erin Brokovich brought to the national spotlight, is recognized by several national and international governmental bodies as a carcinogen . (phys.org)
- There is an ever-increasing number of norms arising that require quantification of pollutants such as bromated or hexavalent chromium at low concentrations. (news-medical.net)
- The divalent Be and Ni cations were stable in artificial sweat over time (did not precipitate) whereas hexavalent chromium [Cr(VI)] ions decayed over time. (cdc.gov)
- This element also has 2 meta states, 45Crm, the more stable one, and 59Crm, the least stable isotope or isomer. (wikipedia.org)
- The primary decay mode before the most abundant stable isotope, 52Cr, is electron capture and the primary mode after is beta decay. (wikipedia.org)
- This stable isotope disintegrates after living for hundreds of quintillion years, or 40 trillion times the age of the universe. (phys.org)
- This isotope breaks down into a stable isotope of potassium, 39 K or potassium-39. (encyclopedia.com)
- Trafficking of stable isotope-labeled dietary fats was combined with muscle gene expression and magnetic resonance imaging-derived muscle fat content analyses. (diabetesjournals.org)
- Trivalent chromium is the most stable oxidation state for chromium, and it is this form that is found in common nutritional supplements, generally as the picolinate. (drugs.com)
- To date, no chromium-containing biomolecules have been definitively described, and no clinical manifestation of trivalent chromium deficiency in humans has been established. (drugs.com)
- Isotopes of each element contain the same number of protons, but a different number of neutrons. (phys.org)
- The heaviest isotope of an element represents the limit of how many neutrons the nucleus can hold. (phys.org)
- That's 12 more neutrons than the heaviest of the stable calcium isotopes, calcium-48. (phys.org)
- protons and neutrons does each isotope possess? (coursehero.com)
- Another way of defining isotopes, then, is to say that they are different forms of an atom with the same number of protons but different numbers of neutrons. (encyclopedia.com)
- It has a short half-life of about 3.7 million years and decays into one of the four chromium isotopes - element variants with different numbers of neutrons. (asbmb.org)
- This mine is a kimberlite pipe rich in diamonds, and the reducing environment helped produce both elemental chromium and diamond. (newworldencyclopedia.org)
- In its elemental form, chromium has a lustrous steel-gray appearance. (americanelements.com)
- Hydrogen and D/H analysis of apatite by Elemental-Analyzer-Chromium/High Temperature Conversion-Isotope Ratio Mass Spectrometry (EA-Cr/HTC-IRMS). (wesleyan.edu)
- Thermo Delta V Isotope Ratio Mass Spectrometer used extensively for the measurement of 13 C/ 12 C, 15 N/ 14 N, 18 O/ 16 O. The instrument is equipped with gas bench and elemental analyzer inlets. (wisc.edu)
- Chapters 7 and 8 provide technical discourse on the measurement of isotope ratios in elemental or molecular mass spectrometry. (iberlibro.com)
- It is called an "essential trace element" because very small amounts of chromium are necessary for human health. (webmd.com)
- As a result, we know that many foods contain small amounts of chromium, but we are still not sure about exact amounts or how amounts might vary under different circumstances. (whfoods.com)
- Write the oxidation and reduction half-reactions for a silver-chromium voltaic cell. (jiskha.com)
- The catalytic activity of picolinic acid, 1,10-phenanthroline, oxalic acid, 2,2 -bipyridyl and ethylenediamine tetracetic acid have been investigated in the chromium(VI) oxidation of indole in aqueous acetic acid medium. (niscair.res.in)
- OASIC currently has two isotope ratio mass spectrometers (MAT253 and Isoprime 100) and one laser absorption isotopic water analyzer (Los Gatos IWA-35d-EP with auto-injector and water vapor standard source). (lsu.edu)
- Looking at the ratio of stable and unstable isotopes in the nitrogen, Harries found that it was very close to the ratio in the nitrogen that makes up three-quarters of Earth's atmosphere today. (newscientist.com)
- Unlike the popular, related method of standard addition, which usually relies on extensive analytical response (peak area or signal intensity), isotope dilution uses intensive response: the isotope amount ratio. (iberlibro.com)
- This chapter also provides the equations that extend the isotope dilution to more than two isotopes (that is, one isotope ratio). (iberlibro.com)
- Now its primary use is for metal alloys, accounting for 85 percent of the use of chromium. (newworldencyclopedia.org)
- During the 1800s chromium was primarily used as a component of paints and in tanning salts but now metal alloys account for 85% of the use of chromium. (chemeurope.com)
- For part of this work, the iron-chromium system was chosen since it is of considerable technological importance and data on 12% Cr and 17% Cr alloys appeared well. (dtic.mil)
- The organic form of chromium exists in a dinicotino-glutathionine complex in natural foods and is better absorbed than the inorganic form. (drugs.com)
- Although the carcinogenic form of chromium does occur in coal ash, recent research has shown that it also is prevalent in groundwater from aquifers composed of specific Cr-rich rocks. (phys.org)
- The red color of rubies derives from the presence of chromium. (newworldencyclopedia.org)
- To help unravel molecular mechanisms underlying the action of chromium, a metal of major toxicological importance, we grew over 6,000 heterozygous yeast mutants in competition in the presence of chromium. (biomedcentral.com)
- A car bumper is plated with chromium using chromium(III) ions in solution. (jiskha.com)
- Beryllium metal (Be), nickel metal (Ni), and chromium carbide (Cr3C2) particles were characterized and masses of sensitizing ions were measured using established reactant-assisted digestion procedures and extraction in artificial sweat under physiologically relevant conditions. (cdc.gov)
- Chromium ions released into artificial sweat were speciated to understand valence states. (cdc.gov)
- She became rich and famous by promoting "toxic chromium" scares, co-authored a recent letter with the radical Environmental Working Group raising Cr-6 alarms, and will speak on election eve at Catawba College in North Carolina to stir things up still further. (cfact.org)
- The datasets from the heterozygote screen represent an important public resource that may be exploited to discover the toxic mechanisms of chromium. (biomedcentral.com)
- Researchers from Michigan State University and the RIKEN Nishina Center in Japan discovered eight new rare isotopes of the elements phosphorus, sulfur, chlorine, argon, potassium, scandium and, most importantly, calcium. (phys.org)
- Chromium was obtained from the potassium dichromate (K 2 Cr 2 O 7 ). (scielo.br)
- As an example, potassium has a radioactive isotope with mass number 40, 40 K or potassium-40. (encyclopedia.com)
- Deposits of native chromium metal are rare, but they have been discovered. (newworldencyclopedia.org)
- citation needed] A spike in chromium contained in ancient rock deposits formed underwater shows the accumulation had been washed off from the continental shelves. (wikipedia.org)
- And characteristics of chromium deposits in ancient layers of rock became a great indicator of how much O2 was in the atmosphere. (eurekalert.org)
- Though native chromium deposits are rare, some native chromium metal has been discovered. (chemeurope.com)
- II: Clumped Isotope Thermometry of Carbonate Phases Associated with the Copper Deposits of Kennecott, Alaska. (caltech.edu)
- Chromium deficiency. (webmd.com)
- Taking chromium by mouth is effective for preventing chromium deficiency. (webmd.com)
- We have seen evidence of chromium deficiency leading to abnormally high blood sugar as well as evidence that restoring chromium supply back toward normal or higher can enhance blood sugar control even in some people with diabetes. (whfoods.com)
- Chromium (chemical symbol Cr , atomic number 24) is a hard, shiny, steel-gray metal that takes a high polish and does not tarnish. (newworldencyclopedia.org)
- Chromium (atomic symbol: Cr, atomic number: 24) is a Block D, Group 6, Period 4 element with an atomic weight of 51.9961. (americanelements.com)
- Chromium ( pronounced /ˈkroʊmiəm/ ) is a chemical element which has the symbol Cr and atomic number 24. (chemeurope.com)
- Some evidence shows that taking chromium picolinate (a chemical compound that contains chromium) by mouth, either alone or along with biotin, can lower fasting blood sugar, lower insulin levels, and help insulin work in people with type 2 diabetes. (webmd.com)
- Also, chromium picolinate might decrease weight gain and fat accumulation in people with type 2 diabetes who are taking a class of antidiabetes medications called sulfonylureas. (webmd.com)
- Early research shows that chromium picolinate might have the same benefits in people with type 1 diabetes, people who have diabetes as a result of steroid treatment, and people with diabetes the develops during pregnancy. (webmd.com)
- chromium picolinate 60 to 1,000 mcg/day. (drugs.com)
- Limited animal experimentation showed skeletal and neurological defects in the offspring of mice fed chromium picolinate. (drugs.com)
- 7 , 10 , 11 , 12 The US Food and Drug Administration concludes that, based on very limited credible evidence, chromium picolinate may reduce the risk of insulin resistance and therefore may reduce the risk of type 2 diabetes. (drugs.com)
- About 15 million tons of marketable chromite ore were produced in 2000 and converted into roughly four million tons of ferrochrome (consisting of 70 percent chromium alloyed with iron), with an approximate market value of 2.5 billion U.S. dollars. (newworldencyclopedia.org)
- The most common source of chromium is chromite ore (FeCr 2 O 4 ). (americanelements.com)
- The element chromium (Cr) is abundant in the earth's crust and is found in concentrations ranging from 100 to 300 ppm. (drugs.com)
- Two common isotopes of uranium exist, 235 U and 238 U. Of these two, 238 U is much more abundant, making up about 99.3 percent of the uranium found in nature. (encyclopedia.com)
- A radioactive isotope of rubidium is also used to measure the age of very old objects. (encyclopedia.com)
- Rubidium-87 is a radioactive isotope. (encyclopedia.com)
- About 16 artificial radioactive isotopes of rubidium have also been made. (encyclopedia.com)
- Many kinds of rocks contain two rubidium isotopes, rubidium-85 and rubidium-87. (encyclopedia.com)
- Because the amounts of chromium in foods are quite small, researchers have struggled to clearly quantify dietary chromium intake in the same way we can with other nutrients. (whfoods.com)
- The currently accepted value for chromium dietary intake is 25 mcg/day for women and 35 mcg/day for men. (drugs.com)
- No risk of genotoxicity at low dosages over the short-term exists for chromium as a dietary supplement. (drugs.com)
- Researchers from Michigan State University and the RIKEN Nishina Center in Japan have discovered eight new rare isotopes, including the heaviest known calcium atom, calcium-60. (phys.org)
- However, researchers are looking carefully at the results that show chromium might be effective for treating diabetes. (webmd.com)
- Some researchers think that chromium supplements benefit only people with poor nutrition or low chromium levels. (webmd.com)
- Other researchers think that chromium might only help people with diabetes and insulin resistance . (webmd.com)
- In the 1950s, researchers discovered the role of chromium in blood sugar control, a role we describe below in the Role in Health Support section. (whfoods.com)
- The diffusion of (Fe-55) in chromium was studied as an example of a more or less normal tracer element in a possibly abnormal host lattice. (dtic.mil)
- The nitrogen isotope diffusion behaviour is explained by two different states of nitrogen bonding and short-range ordering between nitrogen and chromium. (dtu.dk)