- 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 generalized or localized tissue reaction occurring within minutes of an antigen-antibody reaction. Similar reactions elicited by nonimmunologic mechanisms are termed anaphylactoid reactions. The term anaphylaxis was introduced by C. R. Richet to describe acute adverse reactions which followed reinjection of an eel toxin into dogs. Instead of becoming immune (nonreacting) to the toxin, the animals developed severe and often fatal congestion and hemorrhage of the gastrointestinal tract, lungs, pleura, and endocardium.
Industry:Science
A generator of radio-frequency (rf) signals for wireless communication over some distance, which can vary from the short ranges within a building to intercontinental distances. Most applications utilize signals from very low frequencies (VLF) to extremely high frequencies (EHF); some applications require frequencies as low as 45 Hz or as high as 100 GHz. The radio-frequency output power varies from a fraction of a watt in emergency beacons and portable equipment to several megawatts in long-range, low-frequency transmitters.
Industry:Science
A generic structure that is employed to restrain a vertical-faced or near-vertical-faced mass of earth. The earth behind the wall may be either the natural embankment or the backfill material placed adjacent to the retaining wall. Retaining walls must resist the lateral pressure of the earth, which tends to cause the structure to slide or overturn.
Industry:Science
A generic term describing a family of iron alloys containing 1.8–4.5% carbon. Cast iron usually is made into specified shapes, called castings, for direct use or for processing by machining, heat treating, or assembly. In special cases it may be forged or rolled moderately. Generally, it is unsuitable for drawing into rods or wire, although to a limited extent it has been continuously cast into rods and shapes from a liquid bath or swaged from bars into smaller-dimensional units. Silicon usually is present in amounts up to 3%, but special compositions are made containing up to 6% (Silal) and up to 12% (Duriron).
Industry:Science
A generic term for a device designed to produce electromagnetic radiation in the form of light, heat, ultraviolet energy, or a combination of the three. The term lamp is applied to the entire range of sources, including flame sources (such as kerosine lamps or gas lamps with Welsbach mantles), incandescent sources, and electric arc discharge sources. Used with a modifier, such as ultraviolet, infrared, or sun, the term lamp is used to indicate sources that radiate energy in the ultraviolet or infrared portions of the electromagnetic spectrum (plus some radiation in the visible part of the spectrum).
Industry:Science
A generic term for a family of 209 chlorinated isomers of biphenyl. The biphenyl molecule is composed of two six-sided carbon rings connected at one carbon site on each ring. Ten sites remain for chlorine atoms to join the biphenyl molecule. While the rules of nomenclature would indicate that the term polychlorinated biphenyl can refer only to molecules containing more than one chlorine atom, the term has been used to refer to the biphenyl molecule with one to ten chlorine substitutions.
Industry:Science
A generic term for any member of a large class of proteins associated with nucleic acid molecules. Nucleoprotein complexes occur in all living cells and viruses, where they play vital roles in deoxyribonucleic acid (DNA) replication, transcription, ribonucleic acid (RNA) processing, and protein synthesis. The chemistry of the nucleoproteins has become one of the fastest-growing areas in cell and molecular biology. Developments in this field have already revolutionized our understanding of complex biological processes within a cell. These advances will have important consequences in the treatment of genetic disease, viral infections, and cancer.
Industry:Science
A generic term for downslope movement of soil and rock, primarily in response to gravitational body forces. Mass wasting is distinct from other erosive processes in which particles or fragments are carried down by the internal energy of wind, running water, or moving ice and snow. Mass wasting generally creates colluvium, a type of deposit over or at the bottom of many slopes and with characteristics as varied as the mass-wasting processes.
Industry:Science
A generic term referring to the integration of communications services transported over digital facilities such as wire pairs, coaxial cables, optical fibers, microwave radio, and satellites. ISDN provides end-to-end digital connectivity between any two (or more) communications devices. Information enters, passes through, and exits the network in a completely digital fashion.
Industry:Science
A genus (<i>Quercus</i>) of trees, some of which are shrubby, with about 200 species, mainly in the Northern Hemisphere. About 50 species are native in the United States. All oaks have scaly winter buds, usually clustered at the ends of the twigs, and single at the nodes. The fruit is a nut (acorn) surrounded at the base by an involucre, the acorn cup. The pith is star-shaped. The leaves are simple and usually lobed.
Industry:Science
