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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 branch of science that deals with the measurement or detection of radiant electromagnetic energy. Radiometry is divided according to regions of the spectrum in which the same experimental techniques can be used. Thus, vacuum ultraviolet radiometry, intermediate-infrared radiometry, far-infrared radiometry, and microwave radiometry are considered separate fields, and all of these are to be distinguished from radiometry in the visible spectral region. Curiously, radiometry in the visible is called radiometry, optical radiation measurement science, or photometry, but it is not called visible radiometry.
Industry:Science
A branch of the environmental and occupational safety health sciences and professions concerned with the protection of people and the environment from possibly harmful effects of radiation, while providing for the utilization of radiation for the benefit of society. Health physicists are interdisciplinary radiation protection and safety specialists whose expertise draws from environmental science, mathematics, medicine, radiological health, radiation biology, chemistry, and physics. The subject requires understanding of the generation, measurement, and characteristics of radiation; environmental transport of radionuclides; dosimetry; effects of radiation in biological systems; and the regulations and recommendations governing the use of radiation. The field has expanded to include nonionizing as well as ionizing sources of radiation.
Industry:Science
A branch of theoretical chemistry that uses a digital computer to model systems of chemical interest. In this discipline, the essential physics that determines molecular behavior is captured in mathematical models and programmed for digital computers. The models are imperfect but have proven remarkably useful.
Industry:Science
A break in the stratigraphic record produced by local erosion or nondeposition and representing a short interval of geologic time. The breaks in deposition are those that would occur within a particular sedimentary environment, rather than those associated with a major change in environment.
Industry:Science
A breed of humped, domestic cattle native to India and belonging to the family Bovidae in the order Artiodactyla. Also known as Brahman, they are probably descended from the wild auroch (<i>Bos taurus</i>), which is considered to be the ancestor of domestic cattle.
Industry:Science
A bright spot of light that sometimes appears on either side of the Sun, the same distance above the horizon as the Sun, and separated from it by an angle of about 22° (see <b>illus.</b>). For higher Sun elevations, the angle increases slightly. These spots are known by many common names: sun dogs, mock suns, false suns, or the 22° parhelia. They usually show a red edge on the side closest to the Sun. On some occasions the entire spectrum of colors can be spread out in the sun-dog spot but, commonly, the red edge is followed by an orange or yellow band that merges into a diffuse white region. The effects result from the refraction by sunlight through small, flat, hexagonal-shaped ice crystals falling through the air such that their flat faces are oriented nearly horizontally.
Industry:Science
A bright-green, basic carbonate of copper (Cu<sub>2</sub>CO<sub>3</sub>-(OH)<sub>2</sub>). Malachite is the most stable copper mineral in natural environments in contact with the atmosphere and hydrosphere. It occurs as an ore mineral in oxidized copper sulfide deposits; as a stain on fractures in rock outcrops; as a corrosion product of copper and its alloys (except in industrial-urban environments, where the basic copper sulfate dominates); as suspended particles in streams and in alluvial sediments; and as encrustations on bronze artifacts in seawater and on coccoliths floating in the oceans. It can be distinguished from other green copper minerals by its effervescence in acid. The combination of hardness (3.5–4 on Mohs scale) ideal for carving, color variation in concentric layers, and adamantine-to-silky luster has made malachite a highly prized ornamental stone. Its rare blocky-tabular crystals up to 5 mm (0.2 in.), its pseudomorphs after azurite crystals to 2 cm (0.8 in.), and its more common felty tufts perched on bright blue azurite are eagerly sought by mineral collectors.
Industry:Science
A brittle, silvery-gray, metallic chemical element, Ge, atomic number 32, atomic weight 72.59, melting point 937.4°C (1719°F), and boiling point 2830°C (5130°F), with properties between silicon and tin. Germanium is distributed widely in the Earth's crust in an abundance of 6.7 parts per million (ppm). Germanium is found as the sulfide or is associated with sulfide ores of other elements, particularly those of copper, zinc, lead, tin, and antimony.
Industry:Science
A broad collection of methods used to study and analyze the behavior and performance of actual or theoretical systems. Simulation studies are performed, not on the real-world system, but on a (usually computer-based) model of the system created for the purpose of studying certain system dynamics and characteristics. Simulation is both an experimental science and an art or craft in the development of the precise, “valid” model that captures the necessary elements of the system, and the use of the model to analyze system behavior under various scenarios.
Industry:Science
A broad field encompassing all aspects of the study of ice. While many glaciologists focus their attention on glaciers, the largest ice masses on Earth, glaciology also includes the study of ice that forms on rivers, lakes, and the sea; ice in the ground, including both permafrost and seasonal ice such as that which disrupts roads in the spring; and ice that crystallizes directly from the air on structures such as airplanes and antennas. All forms of snow research, including snow hydrology and avalanche forecasting, fall under the broad rubric of glaciology. Even planetary geologists are involved, as two of the moons of Jupiter, Ganymede and Callisto, are believed to be composed largely of ice. This article, however, will be restricted to discussion of glaciers.
Industry:Science
