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- Number of terms: 178089
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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 decomposition of a space <i>E</i> into a family of identical subspaces (fibers). The space of subspaces is called the base space. Fiber bundles arise naturally in many physical situations. The theory of fiber bundles has been applied to gauge theory in physics, and there is a lively interaction centered on ideas related to fiber bundles and gauge theories in which significant results have been contributed in both areas. The development of the mathematical theory of fiber bundles was begun in the 1930s and has numerous applications within mathematics.
Industry:Science
A delayed luminescence, that is, a luminescence that persists after removal of the exciting source. It is sometimes called afterglow.
Industry:Science
A deleterious set of responses which occurs at the subcellular level, stimulated by some injury, and which is often manifested in altered structure or functioning of the affected organism. The concept of disease has been changing as understanding of biological systems has increased. For centuries disease was described in terms of gross changes. Then a major revolution in biology occurred between 1840 and 1860, based largely on the improvement and application of the light microscope. It included the works of Jacob Shleiden and Theodore Schwann, who developed the concept referred to as the cell theory. This theory states that the basic structural and functional unit of all plant and animal life is the cell. R. C. Virchow was the central figure who applied the cell theory to the pathogenesis of human disease. He recognized that diseases were the product of the alteration of cell structure and function.
Industry:Science
A delicately flavored spice obtained from the nutmeg tree (<i>Myristica fragrans</i>), a native of the Moluccas, or Spice Islands. The tree is a dark-leafed evergreen 30–60 ft (9–18 m) high, and is a member of the nutmeg family (Myristicaceae). The golden-yellow, mature fruits resemble apricots (see <b>illus.</b>). They gradually lose moisture and when completely ripe, the husk (pericarp) splits open, exposing the shiny brown seed covered with a red, fibrous, aromatic aril which is the mace. The kernel inside the seed coat is the nutmeg of commerce. Fruits are produced throughout the year and are picked when the husks split open. The mace is removed from the husks, flattened, and dried. It is used in making pickles, ketchup, and sauces. When the seeds are thoroughly dried, the shells are cracked off, the kernels are removed and sorted, and often treated with lime to prevent damage by insects. Grated nutmeg is used in custards, puddings, and other sweet dishes, also in various beverages. Nutmeg oil is used in medicine, perfumery, and dentifrices, and in the tobacco industry.
Industry:Science
A departure of an optical image-forming system from ideal behavior. Ideally, such a system will produce a unique image point corresponding to each object point. In addition, every straight line in the object space will have as its corresponding image a unique straight line. A similar one-to-one correspondence will exist between planes in the two spaces.
Industry:Science
A deposit containing spheroidal grains with a mineral cortex, most commonly calcite or aragonite, accreted around a nucleus formed primarily of shell fragments or quartz grains. The term ooid is applied to grains less than 0.08 in. (2 mm) in diameter, and the term pisoid to those greater than 0.08 in. (2 mm). Accretionary layering (growth banding) is usually developed clearly. A flattened or elongate shape may occur if the nucleus shows that form. Ooids formed on nuclei of shells and shell fragments and composed of fine, radial calcite are shown in <b>illus. <i>a</i></b>. These ooids are cemented by coarse, clear calcite. Growth banding is visible in most ooids. The pisoids shown in illus. <i>b</i> are composed of many thin layers of very small, tangential (lighter layers) and radial (darker layers) aragonite crystals. These pisoids are cemented with fibrous aragonite.
Industry:Science
A deposit of sediment at the mouth of a river or tidal inlet. The name, from the Greek letter Δ, was first used by Herodotus (fifth century <small>B.C.</small>) for the triangular delta of the Nile. It is also used for storm washovers of barrier islands and for sediment accumulations at the mouths of submarine canyons.
Industry:Science
A derivative of hydrocarbon in which all of the hydrogen atoms are replaced by the –C≡N group. Only two cyanocarbons, dicyanoacetylene and dicyanobutadiyne, were known before 1958. Since then, tetracyanomethane, hexacyanoethane, tetracyanoethylene, hexacyanobutadiene, and hexacyanobenzene were synthesized.
Industry:Science
A derivative of isocyanic acid. Isocyanates are represented by the general formula R–N=C=O, where R is predominantly alkyl or aryl; however, stable isocyanates in which the N=C=O group is linked to elements such as sulfur, silicon, phosphorus, nitrogen, or the halogens have also been prepared. Most members of this class of compounds are liquids that are sensitive to hydrolysis and are strong lacrimators. Isocyanates are extremely reactive, especially toward substrates containing active hydrogen. They have found wide use in the commercial manufacture of polyurethanes, which are used in making rigid and flexible foam, elastomers, coatings, and adhesives.
Industry:Science
A description of the response of a system in equilibrium to a change in one of the variables determining the equilibrium. Le Chatelier's principle is often stated as the following: For a system in equilibrium, a change in a variable shifts the equilibrium in the direction that opposes the change in that variable. However, this statement is false, since the shift induced by a change in a variable is sometimes in the direction that augments (rather than opposes) the change in the variable. Instead of a single general statement, the response of a system in equilibrium to a change in a variable is best described by a set of particular statements. The following statements are all valid consequences of the laws of thermodynamics.
Industry:Science
