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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.
An intracellular membrane system that is present in all eukaryotic cells. In most cells the endoplasmic reticulum is thought to consist of only one continuous membrane enclosing only a single space. However, in protozoa, some unicellular algae, and possibly some fungi, the endoplasmic reticulum occurs as separate, multiple vesicles.
Industry:Science
An iron-core inductor in which the effective inductance is changed by varying the permeability of the core. Saturable-core reactors are used to control large alternating currents where rheostats are impractical. Theater light dimmers often employ saturable reactors.
Industry:Science
An iron-core transformer with movable core. A differential transformer produces an electrical output voltage proportional to the displacement of the core. It is used to measure motion and to sense displacements. It is also used in measuring devices for force, pressure, and acceleration that are based on the conversion of the measured variable to a displacement.
Industry:Science
An iron-magnesium-rich layer silicate; it is also known as black mica. Biotite is the most abundant of the mica group of minerals. The name is derived from that of the French chemist J. Biot. The formula for the ideal end member, phlogopite, is KMg<sub>3</sub>AlSi<sub>3</sub>O<sub>10</sub>(OH)<sub>2</sub>. The more general formula is AX<sub>3</sub>Y<sub>4</sub>O<sub>12</sub>(Z)<sub>2</sub>, where A (interlayer cation) = K, Na, Ca, Ba, or vacancies; X (octahedral cations) = Li, Mg, Fe<sup>2+</sup>, Fe<sup>3+</sup>, Al, Ti, or vacancies; and Y (tetrahedral cation) = Fe<sup>3+</sup>, Al, Si; Z = (OH), F, Cl, O<sup>2-</sup>. This formula is more indicative of the wide range of compositions known for this mineral. Biotite has no commercial value, but vermiculite, an alteration product of magnesium-rich biotite, is used as insulation, as packing material, and as an ingredient for potting soils.
Industry:Science
An irreversible increase in the size of the plant. As plants, like other organisms, are made up of cells, growth involves an increase in cell numbers by cell division and an increase in cell size. Cell division itself is not growth, as each new cell is exactly half the size of the cell from which it was formed. Only when it grows to the same size as its progenitor has growth been realized. Nonetheless, as each cell has a maximum size, cell division is considered as providing the potential for growth.
Industry:Science
An island continent situated in the Southern Hemisphere and extending from 10 to 44°S and from 113 to 153°E. Australia's total area (2,941,526 mi<sup>2</sup> or 7,618,517 km<sup>2</sup> for the Australian mainland and 26,383 mi<sup>2</sup> or 68,332 km<sup>2</sup> for the island of Tasmania) is somewhat less than that of the United States. Bounded on the west by the Indian Ocean and on the east by the Pacific Ocean, Australia straddles the Tropic of Capricorn. Originally part of the ancient supercontinent of Gondwanaland, which began to disintegrate 200 million years ago, Australia broke away from what is now Antarctica about 70 million years ago and began its long drift northward to its present position. Australia's long-term isolation has contributed to the uniqueness of its flora and fauna. Australia possesses about 650 species of birds and 400 species of reptiles, a large proportion of which are endemic. Most interesting are its 255 species of mammals, in particular the marsupials (lacking placenta), which include the kangaroo, wallaby, and koala; and the monotremes (egg-laying), which include the platypus and spiny anteater. These animals appear to represent stages along the evolutionary path toward fully developed placental mammals.
Industry:Science
An isolated fertile area, usually limited in extent and surrounded by desert. The term was initially applied to small areas in Africa and Asia typically supporting trees and cultivated crops with a water supply from springs and from seepage of water originating at some distance. However, the term has been expanded to include areas receiving moisture from intermittent streams or artificial irrigation systems. Thus the floodplains of the Nile and Colorado rivers can be considered vast oases, as can arid areas irrigated by humans.
Industry:Science
An isolated wave that propagates without dispersing its energy over larger and larger regions of space. In most of the scientific literature, the requirement that two solitons emerge unchanged from a collision is also added to the definition; otherwise the disturbance is termed a solitary wave.
Industry:Science
An object is defined as chiral if it is not superimposable on its mirror image. Chirality takes on great significance in organic chemistry. Many molecules, natural and synthetic, possess chirality and perform a special function which their enantiomer (the nonsuperimposable mirror image) cannot accomplish. Chiral molecules may act as catalysts; that is, a small amount of a chiral catalyst, when added to a reaction, may accelerate or make possible the reaction, while remaining unchanged itself. Research in the design and synthesis of chiral ferrocene derivatives has provided catalysts to perform specific functions. The importance of this class of molecules is increasing in research and in industrial applications.
Industry:Science
An object or device that produces a magnetic field. Magnets are essential for the generation of electric power and are used in motors, generators, labor-saving electromechanical devices, information storage, recording, and numerous specialized applications, for example, seals of refrigerator doors. The magnetic fields produced by magnets apply a force at a distance on other magnets, charged particles, electric currents, and magnetic materials.
Industry:Science
