- 行业: Printing & publishing
- Number of terms: 178089
- Number of blossaries: 0
- Company Profile:
McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
A broad field of study encompassing the production, fate, and effects of natural and synthetic pollutants in the environment. The breadth of this field depends on the definition of environment. It can be defined as narrowly as the home and workplace or as broadly as the entire Earth and its biosphere. Environmental toxicology is truly an interdisciplinary science. The effects of a pollutant on the environment depend on the amount released (the dose) and its chemical and physical properties. Pollutants can be grouped according to their origin and effects.
Industry:Science
A broad mixture of hydrocarbons produced as distillates, as residual materials, or as blends of the two during the refining of crude petroleum. Diesel fuel usually has a distillation range of 390–715°F (200–380°C) and a specific gravity range of 0.760–0.935 (equivalent to 61.2–19.8° on the American Petroleum Institute (API) scale). In addition to these properties, diesel fuel must have <1 weight % sulfur, < 0.1 weight % ash, < 0.5 volume % water and sediment, and a high flash point (greater than 131°F or 55°C).
Industry:Science
A broad range of concepts which have been developed to both describe and prescribe the process of decision making, where a choice is made from a finite set of possible alternatives. Normative decision theory describes how decisions should be made in order to accommodate a set of axioms believed to be desirable; descriptive decision theory deals with how people actually make decisions; and prescriptive decision theory formulates how decisions should be made in realistic settings. Thus, this field of study involves people from various disciplines: behavioral and social scientists and psychologists who generally attempt to discover elaborate descriptive models of the decision process of real humans in real settings; mathematicians and economists who are concerned with the axiomatic or normative theory of decisions; and engineers and managers who may be concerned with sophisticated prescriptive decision-making procedures.
Industry:Science
A broad range of rock types made up of calc-silicate minerals such as garnet, regardless of their association with ores, that originate by replacement of precursor rocks. It was a term originally coined by miners in reference to rock consisting of coarse-grained, calc-silicate minerals associated with iron ores in central Sweden. Ore deposits that contain skarn an gangue are termed skarn deposits; such deposits are the world's premier sources of tungsten. They are also important sources of copper, iron, molybdenum, zinc, and other metals. Skarns also serve as sources of industrial minerals such as graphite, asbestos, and magnesite.
Industry:Science
A brown to black combustible rock that originated by accumulation and subsequent physical and chemical alteration of plant material over long periods of time, and that on a moisture-free basis contains no more than 50% mineral matter. The plant debris accumulated in various wet environments, commonly called peat swamps, where dead plants were largely protected from decay by a high water table and oxygen-deficient water. The accumulating spongy, water-saturated, plant-derived organic material known as peat is the precursor of coal. Over time, many changes of the original vegetable matter are brought about by bacteria, fungi, and chemical agents. The process progressively transforms peat into lignite or brown coal, subbituminous coal, bituminous coal, and anthracite. This progression is known as the coalification series. Increasingly deeper burial under hundreds to thousands of feet of younger sediments is required to advance coalification to the bituminous coal and anthracite stages. The pressure exerted by the weight of the overlying sediment and the heat that increases with depth, as well as the length of exposure to them, determine the degree of coalification reached.
Industry:Science
A brownish-black, low-rank coal defined in the engineering sense by the American Society for Testing and Materials as having a heating value of less than 8300 Btu/lb (4611 kcal/kg), determined on a moist, mineral-matter-free basis. Lignite occurs in two subclasses: lignite A (8300–6300 Btu/lb (4611–3500 kcal/kg)) and lignite B (less than 6300 Btu/lb (3500 kcal/kg)). Vitrinite reflectance of lignite is 0.25–0.38%; however, vitrinite reflectance may be more suitably applied to higher-rank coals. Outside North America, low-rank coal is classified as brown coal, which includes lignite, subbituminous, and most high-volatile C bituminous coal of the North American classification system. Brown coal is divided into soft and hard coal; hard coal is subdivided into dull and bright coal.
Industry:Science
A buoyant mass of ductile rock or sediment that has pierced, or appears to have pierced, overlying rock, known as overburden. The overburden can yield by ductile processes or by brittle faulting (see <b>illus.</b>). Diapirs form by lateral and vertical intrusion of buoyant or nonbuoyant rock. Emplacement of a diapir, known as diapirism, involves piercement of overlying rocks.
Industry:Science
A by-product from the pulping of pine wood by the kraft (sulfate) process. In the kraft process the wood is digested under pressure with sodium hydroxide and sodium sulfide. (The alternate process name, sulfate, is derived from the sodium sulfate used to replace sulfur lost in the process.) The volatilized gases are condensed to yield sulfate turpentine. During the pulping the alkaline liquor saponifies fats and converts the fatty and resin acids to sodium salts. Concentration of the pulping solution (black liquor) prior to recovery of the inorganic pulping chemicals allows the insoluble soaps to be skimmed from the surface. Acidification of the skimmed soap yields crude tall oil.
Industry:Science
A cable that transmits information signals between geographically separated points. The heart of a communications cable is the transmission medium, which may be optical fibers, coaxial conductors, or twisted wire pairs. A mechanical structure protects the heart of the cable against handling forces and the external environment. The structure of a cable depends on the application.
Industry:Science
A cable, primarily for communications, laid on the ocean floor to provide international links. This term is sometimes applied to power cables in water, but these are not usually of great length.
Industry:Science
