- 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.
Any of the glycoproteins in the blood serum that are induced in response to invasion by foreign antigens and that protect the host by eradicating pathogens. Antibodies belong to this group of proteins. An antigen is any substance capable of inducing an immune response. Intact antigens are able to specifically interact with the induced immunoglobulins. Normally, the immune system operates in a state known as self-tolerance, and does not attack the host's own tissues, but occasionally the immune system targets host-specific antigens, resulting in autoimmune disease.
Industry:Science
Fossilized evidence of animal behavior, also known as ichnofossils, biogenic sedimentary structures, bioerosion structures, or lebensspuren. The fossils include burrows, trails, and trackways created by animals in unconsolidated sediment, as well as borings, gnawings, raspings, and scrapings excavated by organisms in harder materials, such as rock, shell, bone, or wood. Some workers also consider coprolites (fossilized feces), regurgitation pellets, burrow excavation pellets, rhizoliths (plant root penetration structures), and algal stromatolites to be trace fossils.
Industry:Science
Essentially, linear high polymers comprising heterocyclic rings, or groups of rings, linked together by one or more covalent bonds. As the search has continued for polymeric materials having useful properties at high temperatures (500°C or 930°F or higher), much attention has been given to heterocyclic polymers. The possibility of forming rigid molecules that can be ordered into anisotropic arrays having exceptional stiffness may become of even greater interest. As a group such polymers are often both mechanically rigid and inherently resistant to thermal degradation.
Industry:Science
Arbitrarily defined measures of the resistance of a material to indentation under static or dynamic load, to scratch, abrasion, or wear, or to cutting or drilling. Standardized tests compare similar materials according to the particular aspect of hardness measured by the test. Widely used tests for metals are Brinell, Rockwell, and Scleroscope tests, with modifications depending upon the size or condition of the material. Indentation tests compare species of wood or flooring materials, and abrasion tests serve as an index of performance of stones and paving materials.
Industry:Science
For centuries, the study and findings of anatomy have traditionally been recorded in anatomical atlases—books of two-dimensional pictures representing three-dimensional structures. The early atlases contained idealized illustrations of anatomical features to give the viewer some sense of their three-dimensionality. Many modern atlases use photographs of actual dissections. These often contain artist renderings in order to make the photographs more understandable. Still, all atlases rely on two-dimensional art forms to represent complicated three-dimensional structures.
Industry:Science
Any natural earthy material that decolorizes mineral and vegetable oils and has high sorbent capacity for water and oil. The term fuller's earth has no genetic or mineralogic significance. However, the most common earthy materials classed as fuller's earth are calcium montmorillonites and palygorskites (attapulgites) and sepiolites. The term originated in England, where in ancient times raw wool was cleaned by kneading it in water with clay materials that adsorbed dirt and lanolin. The process was known as fulling, and the clay or earth became known as fuller's earth.
Industry:Science
Experiments in which beams of particles such as electrons, nucleons, alpha particles and other atomic nuclei, and mesons are deflected by elastic collisions with atomic nuclei. Much is learned from such experiments about the nature of the scattered particle, the scattering center, and the forces acting between them. Scattering experiments, made possible by the construction of high-energy particle accelerators and the development of specialized techniques for detecting the scattered particles, are one of the main sources of information regarding the structure of matter.
Industry:Science
Biological diversity, or biodiversity, can be defined simply as the totality and diversity of life at different levels of biological organization. The tremendous diversity in the manifestation of life is the very basis of biological knowledge and existence. Therefore, it is extraordinarily important to all people, including the scientists who study it. The word “biodiversity,” first used in the 1980s, has become ubiquitous in both scientific and common usage (including politics) and is often associated with concerns regarding the natural environment and its conservation.
Industry:Science
In common usage, a fluid motion dominated by rotation about an isolated curved line in space, as in a tornado, a whirlpool, a hurricane, or a similar natural phenomenon. The importance of vortices is due to two characteristics: general fluid flows can be represented by a superposition of vortices; and vortices, once created, have a persistence that increases as the effects of viscosity are reduced. The aerodynamic lift forces and most other contributors to the forces and moments on aircraft and other bodies moving through fluids do not exist in the absence of vortices.
Industry:Science
Commercial clays, or clays utilized as raw material in manufacturing, are among the most important nonmetallic mineral resources. The value of clays is related to their mineralogical and chemical composition, particularly the clay mineral constituents kaolinite, montmorillonite, illite, chlorite, and attapulgite. The presence of minor amounts of mineral or soluble salt impurities in clays can restrict their use. The more common mineral impurities are quartz, mica, carbonates, iron oxides and sulfides, and feldspar. In addition, many clays contain some organic material.
Industry:Science
