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Fluoro Complexes
Fluorine is a chemical element; it has Chemical symbol, symbol F and atomic number 9. It is the lightest halogen and exists at Standard temperature and pressure, standard conditions as pale yellow Diatomic molecule, diatomic gas. Fluorine is extremely Reactivity (chemistry), reactive as it reacts with all other Periodic table, elements except for the light Noble gas, noble gases. It is highly toxicity, toxic. Among the elements, fluorine ranks Abundance of the chemical elements, 24th in cosmic abundance and 13th in crustal abundance. Fluorite, the primary mineral source of fluorine, which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb meaning gave the mineral its name. Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its compounds, and several early experimenters died or sustained injuries from their attempts. Only in 1886 did French chemist He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Element
A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its atomic nucleus, nucleus. Atoms of the same element can have different numbers of neutrons in their nuclei, known as isotopes of the element. Two or more atoms can combine to form molecules. Some elements form Homonuclear molecule, molecules of atoms of said element only: e.g. atoms of hydrogen (H) form Diatomic molecule, diatomic molecules (H). Chemical compounds are substances made of atoms of different elements; they can have molecular or non-molecular structure. Mixtures are materials containing different chemical substances; that means (in case of molecular substances) that they contain different types of molecules. Atoms of one element can be transformed into atoms of a different element in nuclear reactions, which change an atom's at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manhattan Project
The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada. From 1942 to 1946, the project was directed by Major General Leslie Groves of the United States Army Corps of Engineers, U.S. Army Corps of Engineers. Nuclear physicist J. Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the bombs. The Army program was designated the Manhattan District, as its first headquarters were in Manhattan; the name gradually superseded the official codename, Development of Substitute Materials, for the entire project. The project absorbed its earlier British counterpart, Tube Alloys, and subsumed the program from the American civilian Office of Scientific Research and Development. The Manhattan Project employed nearly 130,000 people at its peak and cost nearly US$2 billion (equivalent to about $ b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Fluoridation
Water fluoridation is the controlled addition of fluoride to Public water supply, public water supplies to reduce tooth decay. Fluoridated water maintains fluoride levels effective for cavity prevention, achieved naturally or through supplementation. In the mouth, fluoride slows tooth enamel Demineralization (physiology), demineralization and enhances remineralization in early-stage cavities. Defluoridation is necessary when natural fluoride exceeds recommended limits. The World Health Organization (WHO) recommends fluoride levels of 0.5–1.5 mg/L, depending on climate and other factors. In the U.S., the recommended level has been 0.7 mg/L since 2015, lowered from 1.2 mg/L. Bottled water often has unknown fluoride levels. Tooth decay affects 60–90% of schoolchildren worldwide. Fluoridation reduces cavities in children, with Cochrane (organisation), Cochrane reviews estimating reductions of 35% in baby teeth and 26% in permanent teeth when no other fluoride s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toothpaste
Toothpaste is a paste or gel dentifrice that is used with a toothbrush to clean and maintain the aesthetics of Human tooth, teeth. Toothpaste is used to promote oral hygiene: it is an abrasive that aids in removing dental plaque and food from the teeth, assists in suppressing halitosis, and delivers active ingredients (most commonly fluoride) to help prevent tooth decay (dental caries) and gum disease (gingivitis).American Dental Association Description of Toothpaste Due to variations in composition and fluoride content, not all toothpastes are equally effective in maintaining oral health. The decline of tooth decay during the 20th century has been attributed to the introduction and regular use of fluoride-containing toothpastes worldwide. Large amounts of swallowed toothpaste can be poisonous. Common colors for toothpaste include white (sometimes with colored stripes or green tint) and blue. History Early toothpastes Since 5000 BCE, the Egyptians made a tooth powder, which cons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoride
Fluoride (). According to this source, is a possible pronunciation in British English. is an Inorganic chemistry, inorganic, Monatomic ion, monatomic Ion#Anions and cations, anion of fluorine, with the chemical formula (also written ), whose salts are typically white or colorless. Fluoride salts typically have distinctive bitter tastes, and are odorless. Its salts and minerals are important Reagent, chemical reagents and industrial chemicals, mainly used in the production of hydrogen fluoride for fluorocarbons. Fluoride is classified as a weak base since it only partially associates in solution, but concentrated fluoride is corrosive and can attack the skin. Fluoride is the simplest fluorine anion. In terms of charge and size, the fluoride ion resembles the hydroxide ion. Fluoride ions occur on Earth in several minerals, particularly fluorite, but are present only in trace quantities in bodies of water in nature. Nomenclature Fluorides include compounds that contain ionic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoxetine
Fluoxetine, sold under the brand name Prozac, among others, is an Antidepressant, antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class used for the treatment of major depressive disorder, Anxiety disorder, anxiety, obsessive–compulsive disorder (OCD), panic disorder, premenstrual dysphoric disorder, and bulimia nervosa. It is also approved for treatment of major depressive disorder in adolescents and children 8 years of age and over. It has also been used to treat premature ejaculation. Fluoxetine is oral administration, taken by mouth. Common side effects include anorexia (symptom), loss of appetite, nausea, diarrhea, headache, insomnia, trouble sleeping, xerostomia, dry mouth, and sexual dysfunction. Serious side effects include serotonin syndrome, mania, seizures, an increased risk of suicide, suicidal behavior in people under 25 years old, and an increased risk of bleeding. Antidepressant discontinuation syndrome is less likely to occur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atorvastatin
Atorvastatin, sold under the brand name Lipitor among others, is a statin medication used to prevent cardiovascular disease in those at high risk and to treat abnormal lipid levels. For the prevention of cardiovascular disease, statins are a first-line treatment in reducing cholesterol. It is taken by mouth. Common side effects may include diarrhea, heartburn, nausea, muscle pain (typically mild and dose-dependent) and, less frequently, joint pain. Muscle symptoms often occur during the first year and are commonly influenced by pre-existing health issues and the nocebo effect. Most patients can continue therapy with dose adjustment or statin switching. Rare (<0.1%) but serious side effects may include rhabdomyolysis (severe muscle disorder), liver problems and diabetes. Use during may harm the |
Polytetrafluoroethylene
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene, and has numerous applications because it is chemically inert. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a corporate spin-off, spin-off from DuPont (1802–2017), DuPont, which originally invented the compound in 1938. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high-molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances Wetting, wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low polarizability, electric polarizability of fluorine. PTFE has one of the lowest Friction#Coefficient of friction, coefficients of friction of any solid. Polytetrafluoroethylene is used as a non-stick coating for Cookware and bakeware, pans and other Cookware and bakeware, cookware. It is Chemically inert, non-reactive, partly because of the strength of car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refrigerant
A refrigerant is a working fluid used in the cooling, heating, or reverse cooling/heating cycles of air conditioning systems and heat pumps, where they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerants are heavily regulated because of their toxicity and flammability, as well as the contribution of CFC and HCFC refrigerants to ozone depletion and the contribution of HFC refrigerants to climate change. Refrigerants are used in a direct expansion (DX) circulating system to transfer energy from one environment to another, typically from inside a building to outside or vice versa. These can be air conditioner cooling only systems, cooling & heating reverse DX systems, or heat pump and heating only DX cycles. Refrigerants are controlled substances that are classified by several international safety regulations and, depending on their classification, may only be handled by qualified engineers due to extreme pressure, temperature, flammability, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon–fluorine Bond
The carbon–fluorine bond is a polar covalent bond between carbon and fluorine that is a component of all organofluorine compounds. It is one of the strongest single bonds in chemistry (after the B–F single bond, Si–F single bond, and H–F single bond), and relatively short, due to its partial ionic character. The bond also strengthens and shortens as more fluorines are added to the same carbon on a chemical compound. For this reason, fluoroalkanes like tetrafluoromethane (carbon tetrafluoride) are some of the most unreactive organic compounds. Electronegativity and bond strength The high electronegativity of fluorine (4.0 for fluorine vs. 2.5 for carbon) gives the carbon–fluorine bond a significant polarity or dipole moment. The electron density is concentrated around the fluorine, leaving the carbon relatively electron poor. This introduces ionic character to the bond through partial charges (Cδ+—Fδ−). The partial charges on the fluorine and carbon ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hall–Héroult Process
The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) (obtained most often from bauxite, aluminium's chief ore, through the Bayer process) in molten cryolite and electrolyzing the molten salt bath, typically in a purpose-built cell. The process conducted at an industrial scale, happens at 940–980 °C (1700 to 1800°F) and produces aluminium with a purity of 99.5-99.8%. Recycling aluminum, which does not require electrolysis, is thus not treated using this method. The Hall–Héroult process consumes substantial electrical energy, and its electrolysis stage can produce significant amounts of carbon dioxide if the electricity is generated from high-emission sources. Furthermore, the process generates fluorocarbon compounds as byproducts, contributing to both air pollution and climate change. Process Difficulties faced Elemental aluminium cannot be produced by the electrolysis of an aqueous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryolite
Cryolite ( Na3 Al F6, sodium hexafluoroaluminate) is a rare mineral identified with the once-large deposit at Ivittuut on the west coast of Greenland, mined commercially until 1987. It is used in the reduction ("smelting") of aluminium, in pest control, and as a dye. History Cryolite was first described in 1798 by Danish veterinarian and physician (1740–1801), from rock samples obtained from local Inuit who used the mineral for washing their hides; the actual source of the ore was later discovered in 1806 by the explorer Karl Ludwig Giesecke. who found the deposit at Ivigtut (old spelling) and nearby Arsuk Fjord, Southwest Greenland, where it was extracted by Øresund Chemical Industries. The name is derived from the Greek words (), and (). The Pennsylvania Salt Manufacturing Company used large amounts of cryolite to make caustic soda and fluorine compounds, including hydrofluoric acid at its Natrona, Pennsylvania, works, and at its integrated chemical plant in Cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
