- 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 calcarenite or clastic limestone whose detrital particles are chiefly fossils, whole or fragmented. The term is most frequently used for an aggregate of large shells more or less cemented by calcite. If the rock consists of fine-sized shell debris, it is called a microcoquina. Encrinite is a microcoquina made up primarily of crinoid fragments (see <b>illus.</b>). Some coquinas show little evidence of any transportation by currents; articulated bivalves are preserved in entirety and the shells are not broken or abraded.
Industry:Science
A calcium, titanium silicate, , of high titanium content. Titanite is also known as sphene.
Industry:Science
A carbohydrate that occurs as discrete, partially crystalline granules in the seeds, roots (tubers), stems (pith), leaves, fruits, and pollen grains of higher plants. Starch functions as the main storage or reserve form of carbohydrate; it is second in abundance only to cellulose, a major structural component of plants. Cereal grains, tuber and root crops, and legumes (seeds) have long been used as major sources of carbohydrate in human diets.
Industry:Science
A carnivore classified in the family Mustelidae along with martens and fishers. The sable (<i>Martes zibellina</i>) has a very slender, long, and supple body (see <b>illustration</b>). Coloration varies but is usually dark brown on the back and slightly lighter on the flanks, belly, and head. The winter pelage (the coat, which includes fur plus longer, coarser guard hairs) is long, silky, and luxurious with a particularly strong, thick undercoat; the summer pelage is shorter, coarser, duller, and darker. The legs and tail are dark. The limbs are short and terminate in five toes with semiretractile claws. The soles of the feet are covered with extremely dense, stiff hairs. The bushy tail serves as a balancing rod. The dental formula is I 3/3, C 1/1, PM 4/4, M 1/2 × 2, for a total of 38 teeth. Adult sables have a head and body length of 35–55 cm (14–22 in.), including a tail length of 12–19 cm (5–7 in.). They weigh 0.5–2 kg (1–4 lb).
Industry:Science
A carnivore long classified in the subfamily Mephitinae in the family Mustelidae (otters, weasels, mink, badgers, and their relatives), but since 1997 placed in the independent family Mephitidae along with the Oriental stink badger <i>Mydaus</i>. This new placement was based on convincing DNA evidence linking skunks (genera <i>Mephitis</i>, <i>Spilogale</i>, and <i>Conepatus</i>) and <i>Mydaus</i> genetically.
Industry:Science
A carnivorous mammal in the family Mustelidae along with weasels and otters. Badgers originated in Asia and are currently found from Ireland to Japan and the Philippine Islands as well as in North America. They occupy a wide range of habitats including open plains, semidesert, and the boreal forests of Scandinavia and Russia. In parts of Russia, they occur as far north as the Arctic Circle. Worldwide there are ten species of badgers classified in six genera (see <b>table</b>).
Industry:Science
A catalytic protein produced by living cells. The chemical reactions involved in the digestion of foods, the biosynthesis of macromolecules, the controlled release and utilization of chemical energy, and other processes characteristic of life are all catalyzed by enzymes. In the absence of enzymes, these reactions would not take place at a significant rate. Several hundred different reactions can proceed simultaneously within a living cell, and the cell contains a comparable number of individual enzymes, each of which controls the rate of one or more of these reactions. The potentiality of a cell for growing, dividing, and performing specialized functions, such as contraction or transmission of nerve impulses, is determined by the complement of enzymes it possesses. Some representative enzymes, their sources, and reaction specificities are shown in the <b>table</b>.
Industry:Science
A catalytic, high-pressure process flexible enough to produce either of the two major light fuels—high octane gasoline or aviation jet fuel. It proceeds by two main reactions: adding hydrogen to molecules too massive and complex for gasoline and then cracking them to the required fuels. The process is carried out by passing oil feed together with hydrogen at high pressure (1000–2500 lb/in.<sup>2</sup> gage or 7–17 megapascals) and moderate temperatures (500–750°F or 260–400°C) into contact with a bifunctional catalyst, comprising an acidic solid and a hydrogenating metal component. Gasoline of high octane number is produced, both directly and through a subsequent step such as catalytic reforming; jet fuels may also be manufactured simply by changing conditions with the same catalysts. The process is characterized by a long catalyst life (2–4 years), though a slow decline in activity occurs, caused by the deposition of carbonaceous material on the catalyst. Regeneration at intervals by burning off these deposits restores the activity, but eventually the catalyst porosity is destroyed and it must be replaced.
Industry:Science
A catecholamine neurotransmitter that is synthesized by certain neurons in the brain and interacts with specific receptor sites on target neurons.
Industry:Science
A cathode-ray tube, or CRT, used as a television display. A cathode-ray tube has an electron gun, electromagnetic deflection yoke, shadow mask or grill assembly, and a phosphor screen that is the light emitter (see <b>illustration</b>). All of this is contained in a glass envelope. Television picture tubes are largely being replaced by flat-panel displays, such as liquid-crystal displays.
Industry:Science
