A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0-9 hydroboration ... hydroxylamine hydroboration (from the article "borane") ..."for his studies on the structure of boranes illuminating problems of chemical bonding," while one ... hydrobromic acid (from the article "Names of common acids") ...Other bromine compounds of significance include hydrogen bromide (HBr), a colourless gas used as a ... Hydrobryum (from the article "Podostemaceae") ...(25 species, Central America and northwestern tropical South America), Podostemum (17 species, worldwide tropics and ... hydrocarbon any of a class of organic chemical compounds composed only of the elements carbon (C) ... [29 Related Articles] hydrocele excessive accumulation of fluids in the scrotal sac that surrounds the testes in the male ... Hydrocenidae (from the article "gastropod") ...marine shells (Neritidae), with some freshwater dwellers, particularly in Indonesia and the Philippines (Neritidae), and ... hydrocephalus accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain, causing progressive enlargement ... [7 Related Articles] Hydrocharitaceae the frog's-bit family of monocotyledonous flowering plants, with 18 genera of submerged and emergent, freshwater ... hydrochloric acid (from the article "hydrochloric acid") corrosive, colourless acid that is prepared by dissolving gaseous hydrogen chloride in water (see hydrogen ... hydrochlorofluorocarbon (from the article "The Environment") ...that had ratified the 1987 Montreal Protocol on Substances That Deplete the Ozone Layer, together ... Hydrocleys genus of perennial aquatic plants of the family Limnocharitaceae, consisting of three or four species, ... hydrocooling (from the article "fruit processing") ...fruits are moved to storage. In the case of highly heat-sensitive products such as raspberries ... hydrocoral (from the article "cnidarian") ...known as true jellyfishes, for the medusa form is larger and better known than the ... Hydrocorisae (from the article "heteropteran") ...or ocelli, present or absent; scent glands usually present; gradual metamorphosis; widely distributed, terrestrial and ... hydrocracking (from the article "petroleum refining") ...products. Catalytic reforming of naphtha replaced the earlier thermal reforming process and became the leading ... hydrocyanic acid (from the article "Names of common acids") Fresh cassava leaves are rich in protein, calcium, and vitamins A and C. Their prussic ... Hydrocynus (from the article "tigerfish") any of several fishes so named on the basis of their pugnacity when caught, their ... Hydrocynus goliath (from the article "tigerfish") ...one or several dark, lengthwise stripes and are swift, voracious, salmon-shaped carnivores with daggerlike teeth ... Hydrocynus vittatus (from the article "tigerfish") ...that protrude when the mouth is closed. There are about five species; the largest (H. ... hydrodesulfurization (from the article "organosulfur compound") ...in turn generated from microbial action on sulfate in rocks. As the oil ages, the ... Hydrodictyon (from the article "Hydrodictyon") genus of green algae known as water nets (q.v.). hydrodynamic brake (from the article "brake") A hydrodynamic (fluid) brake has a rotor (rotating element) and a stator (stationary element) that ... hydrodynamic concept (from the article "ear, human") ...contain, the pressure it exerts varying with the head position. In 1873 the Austrian scientists ... hydrodynamic film (from the article "bearing") Under certain combinations of load, speed, fluid viscosity, and bearing geometry, a fluid film forms ... hydrodynamic trapping (from the article "petroleum") ...by a denser, relatively impermeable cap rock (e.g., shale or evaporites). The trap may be ... hydrodynamics (from the article "fluid mechanics") Hydrodynamicscontribution byCauchyCauchy, Augustin-Louis, Baron...the Academy ... hydroelectric power electricity produced from generators driven by water turbines that convert the potential energy in falling ... [81 Related Articles] hydrofining (from the article "petroleum refining") Hydrogen processes, commonly known as hydrofinishing, hydrofining, or hydrodesulfurization, are the most common processes for ... hydrofluoric acid (from the article "Names of common acids") Hydrofluoric acid is also used as a catalyst for many alkylation units. The chemical reactions ... hydrofluorination process (from the article "uranium processing") This hydrofluorination process is usually performed in a fluidized-bed reactor. hydrofluorocarbon (from the article "The Environment") Legislation that curbed greenhouse-gas emissions also came into force in July. It introduced requirements on ... hydrofoil underwater fin with a flat or curved winglike surface that is designed to lift a ... [1 Related Articles] hydroformylation (from the article "coordination compound") ...fibres, films, and plastics. Other technologically important processes based on metal complex catalysts include the ... hydrogarnet (from the article "garnet") ...and hydrogrossular [Ca3Al2(SiO4)3 - x(H4O4)x]. Other hydrogarnets have been reported-e.g., hydroandradite and hydrospessartine; the general ... hydrogasification process (from the article "coal utilization") ...produce a mixture of carbon monoxide, hydrogen, and some noncombustible gases, with medium calorific value ... hydrogen a colourless, odourless, tasteless, flammable gaseous substance that is the simplest member of the family ... [96 Related Articles] hydrogen bond (from the article "chemical bonding") The interactions described so far are not limited to molecules of any specific composition. However, ... hydrogen bromide (from the article "bromine") ...film, is, like silver chloride and iodide, light sensitive. Traces of potassium bromate (KBrO3) are ... hydrogen chloride (HCl), a compound of the elements hydrogen and chlorine, a gas at room temperature and ... [8 Related Articles] hydrogen clock (from the article "time") Clocks regulated by hydrogen masers have been developed at Harvard University. The frequency of some ... hydrogen cloud in astronomy, interstellar matter composed of neutral hydrogen atoms. Most of the matter between the ... [3 Related Articles] hydrogen cyanide a highly volatile, colourless, and extremely poisonous liquid (boiling point 26° C [79° F], freezing ... [9 Related Articles] hydrogen electrode (from the article "acid-base reaction") It is often preferable to use a more specific method for determining the concentration of ... hydrogen fluoride (from the article "halogen element") Fluorspar is the most important source of fluorine. In the manufacture of hydrogen fluoride (HF), ... hydrogen fuel cell (from the article "Physical Sciences") Platinum catalysts, because of their high chemical activity, were good candidates for making hydrogen fuel ... hydrogen halide (from the article "halogen element") The halogen elements all form compounds with hydrogen, the hydrogen halides. The energy of the ... hydrogen ion strictly, the nucleus of a hydrogen atom separated from its accompanying electron. The hydrogen nucleus ... [18 Related Articles] hydrogen maser (from the article "maser") In the hydrogen maser, hydrogen atoms are produced in a discharge and, like the molecules ... hydrogen peroxide (H2O2), a colourless liquid usually produced as aqueous solutions of various strengths, used principally for ... [6 Related Articles] hydrogen selenide (from the article "selenium") Selenium combines directly with hydrogen, resulting in hydrogen selenide, H2Se, a colourless, foul-smelling gas that ... hydrogen sulfide (from the article "hydrogen sulfide") colourless, extremely poisonous, gaseous compound formed by sulfur with hydrogen (see sulfur).TABLESJovian atmosphere hydrogen-metal exchange (from the article "metalation") any chemical process by which a metal atom is introduced into an organic molecule to ... hydrogenated amorphous silicon (from the article "amorphous solid") ...the Table, the practical form of this amorphous semiconductor is not pure silicon but a ... hydrogenated FAD (from the article "cell") ...atoms are transferred to the cell's most important hydrogen acceptors, the coenzymes nicotinamide adenine dinucleotide ... hydrogenated NAD (from the article "alcohol consumption") ...ADH and of aldehyde dehydrogenase-require a coenzyme, nicotinamide adenine dinucleotide (NAD), the acceptor of hydrogen ... hydrogenated NBR (from the article "industrial polymers, major") A hydrogenated version, abbreviated as HNBR, is also highly resistant to thermal and oxidative deterioration ... hydrogenation chemical reaction between molecular hydrogen and an element or compound, ordinarily in the presence of ... [16 Related Articles] hydrogenolysis (from the article "hydrogenation") ...simply adds to a double or triple bond connecting two atoms in the structure of ... hydrogenosome (from the article "protist") ...(benthic) ciliates that live in the sulfide zone of certain marine and freshwater sediments. Mitochondria ... hydrography the art and science of compiling and producing charts, or maps, of water-covered areas of ... [3 Related Articles] hydroid (from the article "bryophyte") ...the stem. In the moss subclass Polytrichidae, for example, a complex conducting strand is often ... hydroid any member of the invertebrate order Hydroida (class Hydrozoa, phylum Cnidaria). Hydroids have three basic ... [2 Related Articles] Hydroides (from the article "annelid") ...body divided into thorax and abdomen; tube mucoid or calcareous; size, minute to 50 cm; ... hydroisocyanic acid (from the article "nebula") ...rather unstable species can exist in space because there is not enough energy to convert ... hydrokinetics (from the article "ship construction") ...of practical experience; ship construction was predominantly a skill. With the rapid growth and development ... hydrolaccolith (from the article "permafrost") ...areas of continuous permafrost. The open-system type is generally smaller and forms on slopes when ... hydrolase any one of a class of more than 200 enzymes that catalyze the hydrolysis of ... [2 Related Articles] hydrologic cycle cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many ... [21 Related Articles] hydrologic sciences the fields of study concerned with the waters of the Earth. Included are the sciences ... [2 Related Articles] hydrological map chart showing such hydrologic features as rivers and streams; the purpose and content of these ... hydrology scientific discipline concerned with the waters of the Earth, including their occurrence, distribution, and circulation ... [7 Related Articles] hydrolysis in chemistry and physiology, a double decomposition reaction with water as one of the reactants. ... [11 Related Articles] hydrolyzable tannin (from the article "tannin") Tannins may be classified chemically into two main groups, hydrolyzable and condensed. Hydrolyzable tannins (decomposable ... hydrolyzer process (from the article "soap and detergent") The boiling process is very time consuming; settling takes days. To produce soap in quantity, ... hydromancy (from the article "divination") ...an accusation at a seance around the fire, which will suddenly explode upon the "guilty" ... Hydromantes (from the article "Caudata") ...with 25 genera (including Plethodon in North America and the bolitoglossines Bolitoglossa in Central and ... hydromedusa (from the article "cnidarian") ...jellyfishes, for the medusa form is larger and better known than the polyp form. In ... hydromel (from the article "mead") ...made from honey were common among the ancients of Scandinavia, Gaul, Teutonic Europe, and Greece ... Hydromeles (from the article "gastropod") ...deposit their eggs in the umbilicus, an opening in the shell base. In one species, ... hydrometallation (from the article "organometallic compound") The addition of a metal hydride to a multiple bond is called hydrometallation, and it ... hydrometallurgy extraction of metal from ore by preparing an aqueous solution of a salt of the ... [4 Related Articles] hydrometeor any water or ice particles that have formed in the atmosphere or at the Earth's ... hydrometeorology branch of meteorology that deals with problems involving the hydrologic cycle, the water budget, and ... hydrometer device for measuring some characteristics of a liquid, such as its density (weight per unit ... [2 Related Articles] Hydromys (from the article "water rat") Water rats of the genus Hydromys live in the mountains and coastal lowlands of Australia, ... hydronephrosis (from the article "renal system disease") ...amounts of urine when obstruction is intermittent, and to a mass in the kidney when ... hydronium ion (from the article "acid-base reaction") ...charged ions (cations), such as the ammonium ion (NH4+), which can be derived by the ... hydronymy (from the article "name") ...toponymy, then the uninhabited places (e.g., fields, small parts of forests) are called microtoponymy; names ... hydropathy therapeutic system that professes to cure all disease with water, either by bathing in it ... [1 Related Articles] hydrophane (from the article "opal") ...may crack or lose its colour if it dries, many finished stones are protected by ... hydrophilicity (from the article "The vitamins") ...bonds with other alcohol molecules as well as with water. Because alcohols form hydrogen bonds ... hydrophobic cement (from the article "cement") ...or other filler together with an air-entraining agent or a water-repellent additive. Waterproof cement is ... hydrophobicity (from the article "alcohol") ...alcohol, and t-butyl alcohol are all miscible with water. Alcohols with higher molecular weights tend ... hydrophone device for converting sound waves into electrical signals, similar in operation to a microphone but ... [1 Related Articles] hydrophotometer (from the article "undersea exploration") ...and transparency of the ocean water are indicative of biological activity and of suspended material. ... hydroplane (from the article "Gold Cup") ...The first race for the cup was held on the Hudson River and was won ... hydroponics the cultivation of plants in nutrient-enriched water, with or without the mechanical support of an ... [3 Related Articles] hydrops fetalis (from the article "erythroblastosis fetalis") ...red blood cells); and an enlarged liver and spleen. In its mildest form, the disease ... hydroquinone (from the article "hydroquinone") colourless, crystalline organic compound formed by chemical reduction of benzoquinone. See quinone.formation hydrosilation (from the article "organometallic compound") ...This reaction is driven mainly by the high C&singlehorzbond;H bond strength relative to most E&singlehorzbond;H ... hydroskimming refinery (from the article "petroleum refining") ...produce large quantities of unfinished oils and are highly dependent on local markets, but the ... hydrosol (from the article "sol") ...of very fine particles dispersed in a continuous medium) in which the particles are solid ... hydrosphere discontinuous layer of water at or near the Earth's surface. It includes all liquid and ... [7 Related Articles] hydrostatic balance (from the article "climate") ...is a horizontal temperature gradient in the troposphere. At both the surface and upper levels, ... hydrostatic concept (from the article "ear, human") ...in the opposite direction. This deflection stimulates the hair cells by bending their stereocilia in ... hydrostatic equation (from the article "ocean") ...where g is the acceleration of gravity, rho is the density of seawater, which increases ... hydrostatic film (from the article "bearing") ...surfaces in a sliding bearing; this is known as a hydrodynamic film. An oil film ... hydrostatic skeleton (from the article "animal") Hydrostatic skeletons are the most prevalent skeletal system used by animals for movement and support. ... hydrostatics (from the article "fluid mechanics") It is common knowledge that the pressure of the atmosphere (about 105 newtons per square ... hydrosulfuric acid (from the article "Names of common acids") ...is named with the prefix hydro- and the suffix -ic. For example, HCl dissolved in ... hydrotherapy external use of water in the medical treatment of disease and injury. Its primary value ... [2 Related Articles] hydrothermal metamorphism (from the article "metamorphism") ...pressure; metasomatism, the metamorphism that includes the addition or subtraction of components from the original ... hydrothermal mineral deposit any concentration of metallic minerals formed by the precipitation of solids from hot mineral-laden water ... [3 Related Articles] hydrothermal solution (from the article "mineral deposit") Hydrothermal mineral deposits are those in which hot water serves as a concentrating, transporting, and ... hydrothermal vent (from the article "marine ecosystem") Producers were discovered in the aphotic zone when exploration of the deep sea by submarine ... Hydrothyria venosa (from the article "fungus") ...to dry climates. They prevail in deserts, Arctic and Alpine regions, and ice-free parts of ... hydrotropism (from the article "tropism") ...by active movement or by structural alteration. Forms of tropism include phototropism (response to light), ... hydrous mica any of the illite group of clay minerals, including illite, bramallite (a sodium illite), and ... hydroxamic acid (from the article "carboxylic acid") Other acid derivatives include hydrazides, hydroxamic acids, and acyl azides. These compounds are formally derived ... hydroxide any chemical compound containing one or more groups, each comprising one atom each of oxygen ... [2 Related Articles] hydroxide ion (from the article "Common polyatomic ions") ...effects on vegetable dyes and other properties) and the concentration of hydrogen ions in the ... hydroxide mineral (from the article "mineral deposit") Oxides and hydroxides are a large and diverse group of ore minerals. The major ore ... hydroxy acid (from the article "carboxylic acid") The 2-, 3-, 4-, and 5-hydroxycarboxylic acids all lose water upon heating, although the products ... hydroxyethyl moiety (from the article "metabolism") The hydroxyethyl moiety formed in [34] is immediately transferred to one of the two sulfur ... hydroxyl group (from the article "alcohol") Water and alcohols have similar properties because water molecules contain hydroxyl groups that can form ... hydroxylamine (NH2OH), an oxygenated derivative of ammonia, used in the synthesis of oximes from aldehydes and ... [4 Related Articles]

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