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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.
The fields of inquiry to which the general designation science may be appropriately applied are broadly divided into social science and natural science. The latter is further subdivided into biology and physical science. Physical science is generally considered to include astronomy, chemistry, geology, mineralogy, meteorology, and physics. These overlap more or less, as illustrated by astrophysics, chemical physics, physical chemistry, and geophysics. There is overlap, likewise, between the physical and biological sciences, as seen in biochemistry, biophysics, virology, and the close relation between geology and paleontology. The boundaries implied in all such classifications are artificial and consist of regions where one field shades into another.
Industry:Science
The force retarding an airplane, especially in supersonic flight, as a consequence of the formation of shock waves. Although the physical laws governing flight at speeds in excess of the speed of sound are the same as those for subsonic flight, the nature of the flow about an airplane and, as a consequence, the various aerodynamic forces and moments acting on the vehicle at these higher speeds differ substantially from those at subsonic speeds. Basically, these variations result from the fact that at supersonic speeds the airplane moves faster than the disturbances of the air produced by the passage of the airplane. These disturbances are propagated at roughly the speed of sound and, as a result, primarily influence only a region behind the vehicle.
Industry:Science
Strategies or uniform rules of procedure used in some scientific research with a measure of success. Scientific methods differ in generality, precision, and the extent to which they are scientifically justified. Thus, whereas the experimental method can in principle be used in all the sciences dealing with ascertainable facts, the various methods for measuring the electron charge are specific. The search for increasing quantitative precision involves the improvement or invention of special methods of measurement, also called techniques. All scientific methods are required to be compatible with confirmed scientific theories capable of explaining how the methods work. The most general of all the methods employed in science is called the scientific method.
Industry:Science
The application of thermodynamic principles to systems involving physical and chemical transformations is carried out in order to (1) develop quantitative relationships among the identifiable forms of energy and their conjugate variables, (2) establish the criteria for spontaneous change, for equilibrium, and for thermodynamic stability, and (3) provide the macroscopic base for the statistical-mechanical bridge to atomic and molecular properties. The thermodynamic principles applied are the conservation of energy as embodied in the first law of thermodynamics, the principle of entropy production as embodied in the second law, and the principle of absolute entropy and its statistical thermodynamic formulation as embodied in the third law of thermodynamics.
Industry:Science
Synthetic particles that range from 1 to 100 nanometers in diameter. Semiconductor nanoparticles around 1–20 nm in diameter are often called quantum dots, nanocrystals, or Q-particles. These particles possess short-range structures that are essentially the same as the bulk semiconductors, yet have optical or electronic properties that are dramatically different from the bulk properties. The confinement of electrons within a semiconductor nanocrystal results in a shift of the band gap to higher energy with smaller crystalline size. This effect is known as the quantum size effect. In the strong confinement regime, the actual size of the semiconductor particle determines the allowed energy levels and thus the optical and electronic properties of the material.
Industry:Science
The <i>Wilkinson Microwave Anisotropy Probe</i> is a space-based instrument to measure the very small temperature fluctuations in the cosmic microwave background. The project to develop the <i>Microwave Anisotropy Probe</i> was started in 1994, based on a proposal by Charles L. Bennett. In 2003 it was renamed the <i>Wilkinson Microwave Anisotropy Probe</i> (<i>WMAP</i>) in honor of David T. Wilkinson, a pioneer in observing the cosmic microwave background, who played a major role in the design, construction, and early operation of <i>WMAP</i>. <i>WMAP</i> is the second medium-class Explorer mission to be launched by the National Aeronautics and Space Administration (NASA). Results from the first year of <i>WMAP</i> operation were released in February 2003.
Industry:Science
The Hubble Space Telescope was placed in Earth orbit in April 1990 by astronauts aboard space shuttle <i>Discovery</i>. The telescope, high above the Earth's atmosphere, is designed to receive new observational instrumentation at regular intervals. It was first serviced by astronauts in 1993 as part of a series of planned missions to keep it operating at peak performance. In February 1997, another space shuttle crew placed two new scientific instruments into the Hubble Space Telescope. One, the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), gives the telescope its first infrared observing capability. (Infrared light is emitted at longer wavelengths than human eyes can see.) The NICMOS operates in a wavelength range from 0.8 to 2.5 micrometers.
Industry:Science
The application of Archimedes' principle to the layered structure of the Earth. The elevated topography of Earth is roughly equivalent to an iceberg that floats in the surrounding, denser water. Just as an iceberg extends beneath the exposed ice, the concept of isostasy proposes that topography is supported, or compensated, by a deep root. The buoyant outer shell of the Earth, the crust, displaces the denser, viscous mantle in proportion to the surface elevation. Isostasy implies the existence of a level surface of constant pressure within the mantle, the depth of compensation. Above this surface the mass of any vertical column is equal. Equal pressure at depth can also be achieved by varying density structure or by the regional deflection of the lithosphere.
Industry:Science
The chemical integrating system in animals that lack a vertebral (spinal) column. An endocrine system consists of those glandular cells, tissues, and organs whose products (hormones) supplement the rapid, short-term coordinating functions of the nervous system. Evidence has been presented for hormones in a wide variety of invertebrates. However, the large majority of the published reports pertains to the more highly evolved groups that will be discussed below, the annelids, mollusks, and particularly two classes of arthropods, the insects and crustaceans. Many of the hormones in invertebrates are neurohormones; that is, they are produced by nerve cells. Just as in the vertebrates, a wide variety of functions are regulated by hormones in the invertebrates.
Industry:Science
The force on an object exposed to electromagnetic radiation. It has been known since the days of J. C. Maxwell in the nineteenth century that electromagnetic radiation (which includes visible light) carries both energy and momentum. If radiation impinges on a material body and becomes absorbed, the energy gives rise to heat and is readily detectable. When radiation interacts with an object and is absorbed or scattered, there is also a change in the momentum of the light. By conservation of momentum, this gives rise to a force on the object. This is called radiation pressure. The magnitude of this momentum for visible light is quite small and is difficult to detect. Only near or inside stars, where the intensity is enormous, do light forces have large effects.
Industry:Science
