- 行业: Printing & publishing
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- 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.
Progress in the science of volcanology tends to be episodic and governed by accidents of nature—the volcanic eruptions themselves. Although recent years have not been marked by events as dramatic as those of Mount St. Helens in 1980 or Pinatubo in 1991, for the first time several submarine eruptions have been monitored. Further, ongoing eruptions at Kilauea since 1983 and Montserrat since 1994 have provided unprecedented opportunity to monitor eruptive processes and the underground movement of magma. In addition to this progress based upon direct observation, numerical and analog experiments have led to breakthroughs in understanding the mechanisms of explosive eruptions. Finally, recent symposia on the nature of ocean island volcanism and long lava flows have resulted in advanced understanding of those phenomena.
Industry:Science
Prion diseases, also known as spongiform encephalopathies, are a group of transmissible disorders that affect the brains of humans and animals and are invariably fatal. The nature of the pathogenic agent is unique. In contrast to all other known infectious agents (for example, viruses, bacteria, yeast), which contain nucleic acids as information carriers, the infectious prion pathogen seems to lack this component. The prevailing view is that the molecule responsible for the transmission of the spongiform encephalopathies is the structural isoform of a protein, named prion protein (the term prion is a skewed acronym for proteinaceous infectious agent). The identification of an infectious agent that apparently does not require a nucleic acid for replication presents a fascinating puzzle in modern biology and medicine.
Industry:Science
Materials whose ability to release energy derives from specific properties of the atom's nucleus. In general, energy can be released by combining two light nuclei to form a heavier one, a process called nuclear fusion; by splitting a heavy nucleus into two fragments of intermediate mass, a process called nuclear fission; or by spontaneous nuclear decay processes, which are generically referred to as radioactivity. Although the fusion process may significantly contribute to the world's energy production in future centuries and although the production of limited amounts of energy by radioactive decay is a well-established technology for specific applications, the only significant industrial use of nuclear fuel so far utilizes fission. Therefore, the term nuclear fuels generally designates nuclear fission fuels only.
Industry:Science
Mineral assemblages surrounding ore deposits typically have unique characteristics that create zoning patterns (changes in composition with depth, lateral distance, or both) in a variety of ore deposit environments. These patterns result from the interaction of hydrothermal fluids with the surrounding host rock and may be used to help locate mineralization. Mapping alteration minerals—that is, determining the type and distribution of alteration minerals in a given area—is therefore extremely useful in identifying and outlining mineral deposits. It is a routine part of exploration for hydrothermal mineral deposits and aids in the assessment of exploration properties and the construction of deposit models. Short-wave infrared (SWIR) spectroscopy is used to identify these alteration minerals and focus exploration programs.
Industry:Science
One of a wide variety of materials that contain interacting atomic magnetic moments and also possess some form of disorder, in which the temperature variation of the magnetic susceptibility undergoes an abrupt change in slope, that is, a cusp, at a temperature generally referred to as the freezing temperature, <i>T<sub>f</sub></i>. At temperatures below <i>T<sub>f</sub></i> the spins have no long-range magnetic order, but instead are found to have static or quasistatic orientations which vary randomly over macroscopic distances. The latter state is referred to as spin-glass magnetic order. Below <i>T<sub>f</sub></i> these systems also exhibit magnetic hysteresis and slow relaxation phenomena. Analogous effects are observed in measurements of torque in an applied magnetic field and in electron paramagnetic resonance.
Industry:Science
Much of plant shape is defined by the number and location of branches. A combination of genetics and environment controls plant branching. Plants growing beneath the canopy of a dense forest will not produce many side branches. As a consequence, the available energy can be channeled into the main shoot so it can reach upward into sunlight. On the other hand, species growing on an open plain will be highly branched to extend outward and optimize sun exposure. Breeding desired branching traits has been very important in the course of human agriculture. For example, modern maize (<i>Zea mays</i>, corn) has fewer branches (tillers) than the wild teosinte progenitor. This reduction in tillers seems to be due to enhanced expression of a single gene, <i>TEOSINTE BRANCHED1</i> (<i>TB1</i>), which inhibits bud outgrowth in plants.
Industry:Science
Organic electronic and magnetic materials are being incorporated into electronic devices as alternatives to purely inorganic systems. Most of the physical properties of these materials, such as the ability to conduct electrons, can be custom tailored via the modification of the chemical repeat unit or the addition of one or more functional groups. This has led to an expanding library of materials, phenomena, and innovative devices. In addition, organic-based devices offer mechanical flexibility, lightweight design, and low-cost fabrication, all versatile characteristics uncommon in their inorganic counterparts. The science of the interaction of inorganic materials with organic electronic and magnetic materials is a growing field in its own right, and of particular importance to designing and optimizing electronic devices.
Industry:Science
Research vessels designed to collect quantitative data from the sea's surface, its depths, the sea floor, and the overlying atmosphere. The primary tool for obtaining oceanographic data has been the oceanographic vessel, which has a variety of forms and sizes. The ships can be general purpose or special purpose, and a conventional or radical design. Their primary purpose is to carry scientists and increasingly sophisticated equipment to and from study sites on the ocean's surface, and in some cases below the surface. The ships must have the ability to lower and retrieve instruments by using winches and wires. The ship's equipment and instrumentation must determine precisely the location on the sea surface, and provide suitable communication, data gathering, archiving, and computational facilities for the scientific party.
Industry:Science
Light emitted by a high-speed charged particle when the particle passes through a transparent, nonconducting, solid material at a speed greater than the speed of light in the material. The blue glow observed in the water of a nuclear reactor, close to the active fuel elements, is radiation of this kind. The emission of Cerenkov radiation is analogous to the emission of a shock wave by a projectile moving faster than sound, since in both cases the velocity of the object passing through the medium exceeds the velocity of the resulting wave disturbance in the medium. This radiation, first predicted by P. A. Cerenkov in 1934 and later substantiated theoretically by I. Frank and I. Tamm, is used as a signal for the indication of high-speed particles and as a means for measuring their energy in devices known as Cerenkov counters.
Industry:Science
Nanotechnology is the study and engineering of matter at the dimensions of 1–100 nm where physical, chemical, or biological properties are fundamentally different from those of the bulk material. The nanotechnology paradigm is to modify bulk properties and functionality by controlled manipulations at the nanoscale. Nanotechnology research has dramatically grown within the past 10 years because of recent developments in nanoscale characterization techniques, processes, and understanding of material behavior at the nanoscale. By expanding our understanding and control of matter at such levels, new avenues in product development can be opened. Nano-based science has applications across nearly all economic sectors and allows the development of new technologies with broad commercial potential within the forest products industry.
Industry:Science
