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Nickel Arsenide
Nickel arsenide is a compound of nickel and arsenic and component of the ore nickeline. It is highly toxic and a known carcinogen in humans. Uncontrolled decomposition of nickel arsenide can give rise to further toxic nickel compounds. Toxicity Nickel arsenide was one of the first compounds that revealed the toxicity of nickel. The damage to the miners' lungs was documented by Georgius Agricola in the 16th century: "kupfer-nickel" ores in the Schneeberg mines contained red-colored NiAs mineral originally mistaken for the copper ore, thus the (copper) in the name. The (demon) name was reflecting the damage it did to the health of the workers, in addition to them being unable to extract any copper from this ore. The acute oral LD50 In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose req ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel
Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenic
Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is notoriously toxic. It occurs naturally in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. It has various Allotropes of arsenic, allotropes, but only the grey form, which has a metallic appearance, is important to industry. The primary use of arsenic is in alloys of lead (for example, in car batteries and ammunition). Arsenic is also a common n-type dopant in semiconductor electronic devices, and a component of the III–V compound semiconductor gallium arsenide. Arsenic and its compounds, especially the trioxide, are used in the production of pesticides, treated wood products, herbicides, and insecticides. These applications are declining with the increasing recognition of the persistent tox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickeline
Nickeline or niccolite is the mineral form of nickel arsenide. The naturally-occurring mineral contains roughly 43.9% nickel and 56.1% arsenic by mass, but composition of the mineral may vary slightly. Small quantities of sulfur, iron and cobalt are usually present, and sometimes the arsenic is largely replaced by antimony. This last forms an isomorphous series with breithauptite (nickel antimonide). Etymology and history Medieval miners looking for copper in the German Ore Mountains would sometimes find a red mineral, superficially resembling copper ore. Upon attempting extraction, no copper was produced, and subsequently, the miners would be afflicted with mysterious illness. They blamed a mischievous sprite of German mythology, Nickel (similar to ''Old Nick'') for besetting the copper (German: Kupfer). This German equivalent of "copper-nickel" was used as early as 1694 (other old German synonyms are ''Rotnickelkies'' and ''Arsennickel''). In 1751, Baron Axel Fredrik Crons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinogen
A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruses and bacteria. Most carcinogens act by creating mutations in DNA that disrupt a cell's normal processes for regulating growth, leading to uncontrolled cellular proliferation. This occurs when the cell's DNA repair processes fail to identify DNA damage allowing the defect to be passed down to daughter cells. The damage accumulates over time. This is typically a multi-step process during which the regulatory mechanisms within the cell are gradually dismantled allowing for unchecked cellular division. The specific mechanisms for carcinogenic activity is unique to each agent and cell type. Carcinogens can be broadly categorized, however, as activation-dependent and activation-independent which relate to the agent's ability to engage dir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgius Agricola
Georgius Agricola (; born Georg Bauer; 24 March 1494 – 21 November 1555) was a German Humanist scholar, mineralogist and metallurgist. Born in the small town of Glauchau, in the Electorate of Saxony of the Holy Roman Empire, he was broadly educated, but took a particular interest in the mining and refining of metals. He was the first to drop the Arabic definite article ''al-'', exclusively writing ''chymia'' and ''chymista'' in describing activity that we today would characterize as chemical or alchemical, giving chemistry its modern name. For his groundbreaking work '' De Natura Fossilium'' published in 1546, he is generally referred to as the father of mineralogy and the founder of geology as a scientific discipline.Rafferty, John P. (2012). ''Geological Sciences; Geology: Landforms, Minerals, and Rocks''. New York: Britannica Educational Publishing, p. 10. He is well known for his pioneering work '' De re metallica libri XII'', that was published in 1556, one yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schneeberg, Saxony
Schneeberg is a town in Saxony’s district of Erzgebirgskreis. It has roughly 16,400 inhabitants and belongs to the Town League of Silberberg (''Städtebund Silberberg''). It lies 4 km west of Aue, and southeast of Zwickau. Geography Location Schneeberg lies on the Silver Road in the upper western Ore Mountains. Visible from afar is the prominent church of St. Wolfgang. The heart of the town lies on the ''Schneeberg'', which reaches 470 metres above sea level and is also the town’s namesake. Among the surrounding peaks are the ''Gleesberg'' (593 m) to the east and the ''Keilberg'' (557 m) to the north. History Schneeberg’s more than 500-year-long history has been shaped by mining more than anything else, laying the very groundwork for the town’s founding. The original silver mining also yielded cobalt and bismuth mining by the mid 16th century. When uranium mining was being undertaken between 1946 and 1958, the town’s population quickl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demon
A demon is a malevolent supernatural entity. Historically, belief in demons, or stories about demons, occurs in folklore, mythology, religion, occultism, and literature; these beliefs are reflected in Media (communication), media including fiction, comics, film, television series, television, and video games. Belief in demons probably goes back to the Paleolithic, Paleolithic age, stemming from humanity's fear of the unknown, the strange and the horrific.. In Religions of the ancient Near East, ancient Near Eastern religions and in the Abrahamic religions, including History of Judaism, early Judaism and ancient-medieval Christian demonology, a demon is considered a harmful spiritual entity that may cause Spirit possession, demonic possession, calling for an exorcism. Large portions of Jewish demonology, a key influence on Christianity and Islam, originated from a later form of Zoroastrianism, and was transferred to Judaism during the Achaemenid Empire, Persian era. Demons may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of higher toxicity. The term LD50 is generally attributed to John William Trevan. The test was created by J. W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug botox without animal tests. Conventions The LD50 is usually expres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ECHA
The European Chemicals Agency (ECHA; ) is an agency of the European Union working for the safe use of chemicals. It manages the technical and administrative aspects of the implementation of the European Union regulation called Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). ECHA is the driving force among regulatory authorities in implementing the EU's chemicals legislation. ECHA has to ascertain that companies comply with the legislation, advances the safe use of chemicals, provides information on chemicals and addresses chemicals of concern. It is located in Helsinki, Finland and is operational since 2007. ECHA is an independent and mature regulatory agency established by REACH. It is not a subsidiary entity of the European Commission. The agency is headed by Executive Director Sharon McGuinness. Establishment The ECHA was created by European Union regulation dating from 18 December 2006 to manage the then-new legislation to regulate the man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Compounds
Nickel compounds are chemical compounds containing the element nickel which is a member of the group 10 of the periodic table. Most compounds in the group have an oxidation state of +2. Nickel is classified as a transition metal with nickel(II) having much chemical behaviour in common with iron(II) and cobalt(II). Many salts of nickel(II) are isomorphous with salts of magnesium due to the ionic radii of the cations being almost the same. Nickel forms many coordination complexes. Nickel tetracarbonyl was the first pure metal carbonyl produced, and is unusual in its volatility. Metalloproteins containing nickel are found in biological systems. Nickel forms simple binary compounds with non metals including halogens, chalcogenides, and pnictides. Nickel ions can act as a cation in salts with many acids, including common oxoacids. Salts of the hexaaqua ion (Ni2+) are especially well known. Many double salts containing nickel with another cation are known. There are organic acid sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
