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Methylene Diurea
Methylene diurea (MDU) is the organic compound with the formula CH2(NHC(O)NH2)2. It is a white water-soluble solid. The compound is formed by the condensation of formaldehyde with urea. Methylene diurea is the substrate for the enzyme methylenediurea deaminase. Applications MDU is an intermediate in the production of urea-formaldehyde resins. Together with dimethylene triurea, MDU is a component of some controlled-release fertilizer 224px, Methylene diurea (MDU) is component of the most popular controlled-release fertilizers. A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period ...s.{{Ullmann, doi= 10.1002/14356007.n10_n01 , title= Fertilizers, 2. Types , year=2009 , last1=Dittmar , first1=Heinrich , last2=Drach , first2=Manfred , last3=Vosskamp , first3=Ralf , last4=Trenkel , first4=Martin E. , last5=Gutser , first5=Reinhold , last6=Steffens , first6=Günter References F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reaction
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formaldehyde
Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section Forms below), hence it is stored as an aqueous solution (formalin), which is also used to store animal specimens. It is the simplest of the aldehydes (). The common name of this substance comes from its similarity and relation to formic acid. Formaldehyde is an important precursor to many other materials and chemical compounds. In 1996, the installed capacity for the production of formaldehyde was estimated at 8.7 million tons per year. It is mainly used in the production of industrial resins, e.g., for particle board and coatings. Forms Formaldehyde is more complicated than many simple carbon compounds in that it adopts several diverse forms. These compounds can often be used interchangeably and can be interconverted. *Molecular formald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules () with a carbon dioxide () molecule in the urea cycle. Urea is widely used in fertilizers as a source of nitrogen (N) and is an important raw material for the chemical industry. In 1828 Friedrich Wöhler discovered that urea can be produced from inorganic starting materials, which was an important conceptual milestone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylenediurea Deaminase
Methylenediurea deaminase (, ''methylenediurease'') is an enzyme with systematic name ''methylenediurea aminohydrolase'' found in '' Brucella anthropi'', a bacterium. This enzyme catalyses the following chemical reaction: : methylenediurea + 2 H2O \rightleftharpoons N-(hydroxymethyl)urea + 2 NH3 + CO2 (overall reaction) : (1a) methylenediurea + H2O \rightleftharpoons N-(carboxyaminomethyl)urea + NH3 : (1b) N-(carboxyaminomethyl)urea \rightleftharpoons N-(aminomethyl)urea + CO2 (spontaneous) : (1c) N-(aminomethyl)urea + H2O \rightleftharpoons N-(hydroxymethyl)urea + NH3 (spontaneous) Methylenediurea is hydrolysed Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ... and decarboxylated to give an aminated methylurea. References External links * {{Portal bar, Biology, border ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea-formaldehyde
Urea-formaldehyde (UF), also known as urea-methanal, so named for its common synthesis pathway and overall structure, is a nontransparent thermosetting resin or polymer. It is produced from urea and formaldehyde. These resins are used in adhesives, plywood, particle board, medium-density fibreboard (MDF), and molded objects. UF and relate amino resins are a class of thermosetting resins of which urea-formaldehyde resins make up 80% produced worldwide. Examples of amino resins use include in automobile tires to improve the bonding of rubber to in paper for improving tear strength, in molding electrical devices, jar caps, etc. History UF was first synthesized in 1884 by Dr Hölzer, who was working with Bernhard Tollens, neither of whom realized that the urea and formaldehyde were polymerizing. In the following years a large number of authors worked on the structure of these resins. In 1896, Carl Goldschmidt investigated the reaction further. He also obtained an amorphous, almos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylene Triurea
Dimethylene triurea (DMTU) is the organic compound with the formula (H2NC(O)NHCH2NH)2CO. It is a white water-soluble solid. The compound is formed by the condensation of formaldehyde with urea. Both branched and linear isomers exist. Applications DMTU is an intermediate in the production of urea-formaldehyde resins. Together with methylene diurea, DMTU is a component of some controlled-release fertilizer 224px, Methylene diurea (MDU) is component of the most popular controlled-release fertilizers. A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period ...s.{{Ullmann, doi= 10.1002/14356007.n10_n01 , title= Fertilizers, 2. Types , year=2009 , last1=Dittmar , first1=Heinrich , last2=Drach , first2=Manfred , last3=Vosskamp , first3=Ralf , last4=Trenkel , first4=Martin E. , last5=Gutser , first5=Reinhold , last6=Steffens , first6=Günter References Fertilizers Horticulture Ureas< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Controlled-release Fertilizer
224px, Methylene diurea (MDU) is component of the most popular controlled-release fertilizers. A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period). Controlled-release fertilizer is also known as controlled-availability fertilizer, delayed-release fertilizer, metered-release fertilizer, or slow-acting fertilizer. Usually CRF refers to nitrogen-based fertilizers. Slow- and controlled-release involve only 0.15% (562,000 tons) of the fertilizer market (1995). History Controlled-nitrogen-release technologies based on polymers derived from combining urea and formaldehyde were first produced in 1936 and commercialized in 1955. The early product had 60 percent of the total nitrogen cold-water-insoluble, and the unreacted (quick-release) less than 15%. Methylene ureas, e.g. methylene diurea, were commercialized in the 1960s and 1970s, having 25% and 60% of the nitrogen as cold-water-insolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilizers
A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced. For most modern agricultural practices, fertilization focuses on three main macro nutrients: nitrogen (N), phosphorus (P), and potassium (K) with occasional addition of supplements like rock flour for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment or hand-tool methods. Historically fertilization came from natural or organic sources: compost, animal manure, human manure, harvested minerals, crop rotations and byproducts of human-nature industries (i.e. fish processing waste, or bloodmeal from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horticulture
Horticulture is the branch of agriculture that deals with the art, science, technology, and business of plant cultivation. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and non-food crops such as grass and ornamental trees and plants. It also includes plant conservation, landscape restoration, landscape and garden design, construction, and maintenance, and arboriculture, ornamental trees and lawns. The study and practice of horticulture have been traced back thousands of years. Horticulture contributed to the transition from nomadic human communities to sedentary, or semi-sedentary, horticultural communities.von Hagen, V.W. (1957) The Ancient Sun Kingdoms Of The Americas. Ohio: The World Publishing Company Horticulture is divided into several categories which focus on the cultivation and processing of different types of plants and food items for specific purposes. In order to conserve the science of horticultur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
