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Manganese(II) Carbonate
Manganese carbonate is a compound with the chemical formula Mn CO3. Manganese carbonate occurs naturally as the mineral rhodochrosite but it is typically produced industrially. It is a pale pink, water-insoluble solid. Approximately 20,000 metric tonnes were produced in 2005. Structure and production MnCO3 adopts a structure like calcite, consisting of manganese(II) ions in an octahedral coordination geometry. Treatment of aqueous solutions of manganese(II) nitrate with ammonia and carbon dioxide leads to precipitation of this faintly pink solid. The side product, ammonium nitrate is used as fertilizer. Reactions and uses The carbonate is insoluble in water but, like most carbonates, hydrolyses upon treatment with acids to give water-soluble salts. Manganese carbonate decomposes with release of carbon dioxide, i.e. calcining, at 200 °C to give MnO1.88: :MnCO3 + 0.44 O2 → MnO1.8 + CO2 This method is sometimes employed in the production of manganese dioxide, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. It is a trace gas in Earth's atmosphere at 421 parts per million (ppm), or about 0.04% by volume (as of May 2022), having risen from pre-industrial levels of 280 ppm. Burning fossil fuels is the primary cause of these increased CO2 concentrations and also the primary cause of climate change.IPCC (2022Summary for policy makersiClimate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA Carbon dioxide is soluble in water and is found in groundwater, lakes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcining
Calcination refers to thermal treatment of a solid chemical compound (e.g. mixed carbonate ores) whereby the compound is raised to high temperature without melting under restricted supply of ambient oxygen (i.e. gaseous O2 fraction of air), generally for the purpose of removing impurities or volatile substances and/or to incur thermal decomposition. The root of the word calcination refers to its most prominent use, which is to remove carbon from limestone (calcium carbonate) through combustion to yield calcium oxide (quicklime). This calcination reaction is CaCO3(s) → CaO(s) + CO2(g). Calcium oxide is a crucial ingredient in modern cement, and is also used as a chemical flux in smelting. Industrial calcination generally emits carbon dioxide (), making it a major contributor to climate change. A calciner is a steel cylinder that rotates inside a heated furnace and performs indirect high-temperature processing (550–1150 °C, or 1000–2100 °F) within a contro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese Deficiency (medicine)
Manganese deficiency in humans results in a number of medical problems. Manganese is a vital element of nutrition in very small quantities (adult male daily intake 2.3 milligrams). However poisoning may occur when greater amounts are ingested. Function Manganese is a component of some enzymes and stimulates the development and activity of other enzymes. Manganese superoxide dismutase (MnSOD) is the principal antioxidant in mitochondria. Several enzymes activated by manganese contribute to the metabolism of carbohydrates, amino acids, and cholesterol. A deficiency of manganese causes skeletal deformation in animals and inhibits the production of collagen in wound healing. Food sources Manganese is found in leafy green vegetables, fruits, nuts, cinnamon and whole grains. The nutritious kernel, called wheat germ, which contains the most minerals and vitamins of the grain, has been removed from most processed grains (such as white bread). The wheat germ is often sold as lives ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganism
Manganism or manganese poisoning is a toxic condition resulting from chronic exposure to manganese. It was first identified in 1837 by James Couper. Signs and symptoms Chronic exposure to excessive manganese levels can lead to a variety of psychiatric and motor disturbances, termed manganism. Generally, exposure to ambient manganese air concentrations in excess of 5 micrograms Mn/m3 can lead to Mn-induced symptoms. In initial stages of manganism, neurological symptoms consist of reduced response speed, irritability, mood changes, and compulsive behaviors. Upon protracted exposure symptoms are more prominent and resemble those of idiopathic Parkinson's disease, as which it is often misdiagnosed, although there are particular differences in both the symptoms; for example, the nature of the tremors, response to drugs such as levodopa, and affected portion of the basal ganglia. Symptoms are also similar to Lou Gehrig's disease and multiple sclerosis. Causes Manganism has be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematinic
A hematinic is a nutrient required for the formation of blood cells in the process of hematopoiesis. The main hematinics are iron, B12 Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It ..., and folate. Deficiency in hematinics can lead to anaemia. In cases of hematinic deficiency, hematinics can be administered as medicines, in order to increase the hemoglobin content of the blood. Erythropoietin (EPO) is a hormone that stimulates erythropoiesis, which can also be given as a medicine to increase the hemoglobin content of the blood, but EPO is not classified as a hematinic as it is not considered a nutrient, but a hormone. References {{reflist Drugs acting on the blood and blood forming organs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decorative Concrete
Decorative concrete is the use of concrete as not simply a utilitarian medium for construction but as an aesthetic enhancement to a structure, while still serving its function as an integral part of the building itself such as floors, walls, driveways, and patios. The transformation of concrete into decorative concrete is achieved through the use of a variety of materials that may be applied during the pouring process or after the concrete is cured, these materials and/or systems include but are not limited to stamped concrete, acid staining, decorative overlays, polished concrete, concrete countertops, vertical overlays and more. Concrete statues Concrete statues are made by pouring concrete into a latex mold. Often painted and sold for garden ornaments. Most popular designs are bird baths and garden gnomes. Stamped concrete As a modern technique, stamped concrete is the process of adding texture and color to concrete to make it resemble stone, brick, slate, cobblestone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceramic Colorants
{{nofootnotes, date=November 2010Ceramic colorants are added to a glaze or a clay to create color. Carbonates and oxides of certain metals, characterize most colorants including the commonly used cobalt carbonate, cobalt oxide, chrome oxide, red iron oxide, and copper carbonate. These colorants can create a multitude of colors depending on other materials they interact with and to which temperature and in which atmosphere they are fired. Cobalt Cobalt is commonly used in either its carbonate (CoCO3) or its oxide (Co3O4) forms. In the presence of most fluxes, it yields blue colors ranging from low saturation pastels to high saturation midnight blues in both oxidation and reduction atmospheres. However, in the presence of magnesium, cobalt can become purple or pink depending on whether it was fired in oxidation (yields purple) or reduction. Cobalt is also commonly used in black glazes and in washes as decorative medium. Common saturation percentages for low saturation range from ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceramic Glaze
Ceramic glaze is an impervious layer or coating of a vitreous substance which has been fused to a pottery body through firing. Glaze can serve to color, decorate or waterproof an item. Glazing renders earthenware vessels suitable for holding liquids, sealing the inherent porosity of unglazed biscuit earthenware. It also gives a tougher surface. Glaze is also used on stoneware and porcelain. In addition to their functionality, glazes can form a variety of surface finishes, including degrees of glossy or matte finish and color. Glazes may also enhance the underlying design or texture either unmodified or inscribed, carved or painted. Most pottery produced in recent centuries has been glazed, other than pieces in unglazed biscuit porcelain, terracotta, or some other types. Tiles are almost always glazed on the surface face, and modern architectural terracotta is very often glazed. Glazed brick is also common. Domestic sanitary ware is invariably glazed, as are many cera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferrite (magnet)
A ferrite is a ceramic material made by mixing and firing large proportions of iron(III) oxide (Fe2O3, rust) blended with small proportions of one or more additional metallic elements, such as strontium, barium, manganese, nickel, and zinc. They are ferrimagnetic, meaning they can be magnetized or attracted to a magnet. Unlike other ferromagnetic materials, most ferrites are not electrically conductive, making them useful in applications like magnetic cores for transformers to suppress eddy currents. Ferrites can be divided into two families based on their resistance to being demagnetized (magnetic coercivity). Hard ferrites have high coercivity, so are difficult to demagnetize. They are used to make permanent magnets for applications such as refrigerator magnets, loudspeakers, and small electric motors. Soft ferrites have low coercivity, so they easily change their magnetization and act as conductors of magnetic fields. They are used in the electronics industry to make efficien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese Dioxide
Manganese dioxide is the inorganic compound with the formula . This blackish or brown solid occurs naturally as the mineral pyrolusite, which is the main ore of manganese and a component of manganese nodules. The principal use for is for dry-cell batteries, such as the alkaline battery and the zinc–carbon battery.. is also used as a pigment and as a precursor to other manganese compounds, such as . It is used as a reagent in organic synthesis, for example, for the oxidation of allylic alcohols. is α polymorph that can incorporate a variety of atoms (as well as water molecules) in the "tunnels" or "channels" between the manganese oxide octahedra. There is considerable interest in as a possible cathode for lithium-ion batteries. Structure Several polymorphs of are claimed, as well as a hydrated form. Like many other dioxides, crystallizes in the rutile crystal structure (this polymorph is called pyrolusite or ), with three-coordinate oxide and octahedral metal ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the synthesis of organic compounds, and as a fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world production of ethanol was , coming mostly from Brazil and the U.S. Etymology ''Ethanol'' is the systematic name defined by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
