- 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.
More than 400 new species of plants and animals have been discovered on the island of Borneo over the last decade. These include many new plant and insect species, but also several new fish, amphibian, and reptile species. In addition, remarkable discoveries on the genetic origin of three large mammal species have been made.
Industry:Science
One of a class of organic compounds characterized by the structural feature of an oxygen atom linking two hydrocarbon groups, R–O–R′. Ethers are used widely as solvents, both in chemical manufacture and in the research laboratory. The most important ether is ethyl ether, C<sub>2</sub>H<sub>5</sub>OC<sub>2</sub>H<sub>5</sub>.
Industry:Science
One of the most remarkable mechanisms by which the remains of extinct organisms are preserved in the fossil record. In petrifactions (though chiefly in the case of plants rather than animals) the original shape and topography of the tissues, and occasionally even minute cytological details, are retained relatively undeformed.
Industry:Science
Navigation with the aid of celestial bodies, primarily for determination of position when landmarks are not available. In celestial navigation, position is not determined relative to the objects observed, as in navigation by piloting, but in relation to the points on the Earth having certain celestial bodies directly overhead.
Industry:Science
One of the two fundamental constituents of the universe, interconvertible with the other constituent, matter. All physical processes involve exchange of energy, or conversion from one of its named forms (including relativistic mass-energy) into another. The total energy (including mass) of a closed system is a conserved quantity.
Industry:Science
Measurements of the dielectric properties of a material, which are characterized by its complex relative permittivity ε<sub><i>r</i></sub>. For all materials except ferroelectrics, this quantity does not depend on applied field: the general behavior is linear, and so voltage of any convenient magnitude can be used for measurement.
Industry:Science
Polymers are used in numerous applications because of their low weight, high adaptability, and ease of processing. The use of low-weight plastics as packaging material and as a replacement for metal parts in cars reduces transportation costs and environmental impact by lowering fossil fuel consumption and greenhouse-gas emissions.
Industry:Science
One of a series of beta-lactam antibiotics, all of which possess a four-ring beta-lactam structure fused with a five-membered thiazolidine ring. These antibiotics, including penicillin, are nontoxic and kill sensitive bacteria during their growth stage by the inhibition of biosynthesis of their cell-wall mucopeptide (peptidoglycan).
Industry:Science
Medical geology, an emerging field of cooperative research, focuses on the interactions between earth materials and processes with human and animal health. It links geologists and other earth scientists with plant and animal biologists, as well as medical, dental, and veterinary specialists, to resolve local and global health issues.
Industry:Science
One special form of the effective dose 50, or median effective dose. The lethal dose 50, or median lethal dose, is also written as LD<sub>50</sub>. It is used when the response that is being investigated is the death of the experimental animal. The median lethal dose is therefore the dose which is fatal to 50% of the test animals.
Industry:Science
