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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 precession in a magnetic field of the motion of charged particles or of particles possessing magnetic moments.
Industry:Science
A precision instrument used to measure small distances and angles. A common use is on a machinist's caliper, as in the <b>illustration</b>.
Industry:Science
A predatory and voracious species of fish that ranges throughout the tropical and temperate seas of the world, except for the eastern and central Pacific areas. A single species, <i>Pomatomus saltatrix</i> (see <b>illus.</b>), makes up the family Pomatomidae. This fish, also known as the skipjack, is bluish-gray with an average length of 3 ft (1 m) and weight of about 5 lb (2.25 kg). The mouth is large with sharp, strong teeth. The bluefish form schools and migrate north along the Atlantic coast, following schools of smaller fish upon which they prey. The bluefish continue to kill and destroy their prey even after feeding. About June they reach the New England coast, where the young can be found in estuaries and bays.
Industry:Science
A predicted state of nuclear matter containing deconfined quarks and gluons. According to the theory of strong interactions, called quantum chromodynamics, hadrons such as mesons and nucleons (the generic name for protons and neutrons) are bound states of more fundamental objects called quarks. The quarks are confined within the individual hadrons by the exchange of particles called gluons. However, calculations indicate that, at sufficiently high temperatures or densities, hadronic matter should evolve into a new phase of matter containing deconfined quarks and gluons, called a quark-gluon plasma when hot, or quark matter when cold and dense. Such a state of matter is thought to have existed briefly in the very early universe until about 10 microseconds after the big bang, and its cold form might exist today inside the dense cores of neutron stars. One important prediction is that the mechanism, called spontaneous chiral symmetry breaking, that is thought to be responsible for 98% of the mass of the nucleon under normal conditions is not operative in the quark-gluon plasma.
Industry:Science
A predominantly mechanical mixture of a variety of individual gases enveloping the terrestrial globe to form the Earth's atmosphere. In this sense air is one of the three basic components, air, water, and land (atmosphere, hydrosphere, and lithosphere), that form the life zone at the face of the Earth.
Industry:Science
A preeminent association between flowering plants and insects is pollination. Pollination is a mutualism in which two interactors reciprocally benefit: a host plant receives the service of insect pollination in return for a reward provided for its insect pollinator. Typically, the reward is nectar or pollen, but occasionally the provision can be a mating site, resin for nest construction, floral aroma, or even the attraction of plant-generated heat. Evidence from the fossil record and from the inferred ecological and phylogenetic relationships between flowering plants (angiosperms) and their insect pollinators indicates that these types of associations initially were launched during the Early Cretaceous, 125–90 million years ago. It was from this interval of time that flowering plants experienced their initial radiation, as did major groups of insects, especially Thysanoptera (thrips), Coleoptera (beetles), Diptera (flies), Lepidoptera (moths and butterflies), and Hymenoptera (sawflies, wasps, ants, and bees). However, until recently, very little was known about more ancient modes of insect pollination, those that predated the appearance of flowering plants or that occurred before angiosperms became dominant in terrestrial ecosystems.
Industry:Science
A pressure vessel which operates as a fluid source device or shock absorber. It is used to store fluid under pressure or to absorb excessive pressure increases. The hydraulic accumulator is an energy-efficient component, which allows the use of a smaller pump to achieve the same end results in terms of cylinder rod actuation speeds. In certain circuit designs, the accumulator will permit a pump motor to be completely shut down for an extended period of time while the accumulator supplies the necessary fluid to the circuit.
Industry:Science
A pressurized system in which water is vaporized to steam, the desired end product, by heat transferred from a source of higher temperature, usually the products of combustion from burning fuels. Steam thus generated may be used directly as a heating medium, or as the working fluid in a prime mover to convert thermal energy to mechanical work, which in turn may be converted to electrical energy. Although other fluids are sometimes used for these purposes, water is by far the most common because of its economy and suitable thermodynamic characteristics.
Industry:Science
A presumed altered state of consciousness in which the hypnotized individual is usually more susceptible to suggestion than in his or her normal state. In this context, a suggestion is understood to be an idea or a communication carrying an idea that elicits a covert or overt response not mediated by the higher critical faculties (that is, the volitional apparatus).
Industry:Science
A primary, or early differentiated, supporting tissue of young shoot parts appearing while these parts are still elongating. It is located near the surface, usually just under the epidermis (see <b>illus.</b> <i>a</i>). When observed in transverse sections, it is characterized structurally by cell walls that are intermittently thickened, generally in the corners or places of juncture of three or more cells (see illus. <i>b</i> and <i>c</i>). Collenchyma is typically formed in the petioles and vein ribs of leaves, the elongating zone of young stems, and the pedicels of flowers.
Industry:Science
