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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.
Measurement of the time dimension. In practice, horology is the search for a steady or repetitive action, and the design of an instrument to perform that action and to indicate (read out) a measure of the action. Until early in the twentieth century, horology dealt with mechanical instruments, with effort distributed between improving accuracy and decreasing size of timepieces. Increasingly, however, electronic instruments have provided means for meeting these objectives.
Industry:Science
Nuclear excitation caused by the time-dependent long-ranged electric field acting between colliding nuclei. Theoretically, the Coulomb force between the positively charged colliding nuclei is well understood, and the interaction is exactly calculable. Coulomb excitation usually is the dominant reaction in nuclear scattering, and even occurs at low bombarding energies where the separation of the nuclei is sufficiently large that the short-ranged nuclear force does not act.
Industry:Science
Polyolefins, exemplified by polyethylene (PE) and polypropylene (PP), exhibit many useful properties. They are lightweight and possess excellent mechanical strength, flexibility, processability, chemical inertness, and recyclability. Polyolefins, therefore, are cost effective. They are used in the manufacture of numerous products, such as toys, plastic shopping bags, food packages, shampoo and detergent bottles, storage boxes, disposable diapers, sneakers, and car bumpers.
Industry:Science
Satellites dedicated to the observation of meteorological phenomena and atmospheric or surface properties used for weather forecasting. Operational meteorological satellites provide routine observations of weather conditions as well as an ever-expanding range of environmental properties, such as aerosol, dust and ash clouds from volcanic eruptions, ozone, and land vegetation cover. For this reason, they are known in the United States as operational environmental satellites.
Industry:Science
Materials-handling machines that lift and lower a load along a fixed vertical path of travel with intermittent motion. In contrast to hoisting machines, elevating machines support their loads instead of carrying them suspended, and the path they travel is both fixed and vertical. They differ from vertical conveyors in operating with intermittent rather than continuous motion. Industrial lifts, stackers, and freight elevators are the principal classes of elevating machines.
Industry:Science
In the treatment of physical phenomena, it can sometimes be shown that, of all the processes or conditions which might occur, the ones actually occurring are those for which some characteristic physical quantity assumes a minimum value. These processes or conditions are known as minimal principles. The application of minimal principles provides a powerful method of attacking certain problems that would otherwise prove formidable if approached directly from first principles.
Industry:Science
Plate tectonics theory provides an explanation for the present-day tectonic behavior of the Earth, particularly the global distribution of mountain building, earthquake activity, and volcanism in a series of linear belts. Numerous other geological phenomena such as lateral variations in surface heat flow, the physiography and geology of ocean basins, and various associations of igneous, metamorphic, and sedimentary rocks can also be logically related by plate tectonics theory.
Industry:Science
In order to study atmospheric motions, we need to establish spatial coordinates so that the movement of air can be described as a function of space and time. There are many ways to set up such coordinate systems to represent air motions in the atmosphere. The most common one is the classical cartesian coordinate system, the (<i>x,y,z</i>) system, where <i>x</i>, <i>y</i>, and <i>z</i> usually (in meteorology) represent the eastward, northward, and upward (vertical) coordinates.
Industry:Science
Most vertebrates and many invertebrates use sound to communicate. Many species also use light or chemical signals, and some fishes use electric signals. However, sound provides animals with the ability to communicate over long distances and to send signals whose direction is easily determined by the receiver and which are not normally impeded by objects in the environment. A disadvantage is that sound also can be detected by predators which can then find the animal emitting it.
Industry:Science
In many areas of science there is an increasing need for chemical analysis of more complicated samples and for lower detection limits. One consequence is a growing interest in sample preparation procedures to be performed prior to chromatography as a critical step in the analytical scheme. Such procedures would typically achieve a selective removal of unwanted components in the sample and would increase the relative concentration of the target compound before the final analysis.
Industry:Science
