- 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.
A fictitious or pseudo outward force on a particle rotating about an axis which by Newton's third law is equal and opposite to the centripetal force. Like all such action-reaction pairs of forces, they are equal and opposite but do not act on the same body and so do not cancel each other. Consider a mass <i>M</i> tied by a string of length <i>R</i> to a pin at the center of a smooth horizontal table and whirling around the pin with an angular velocity of ω radians per second. The mass rotates in a circular path because of the centripetal force, <i>F</i><sub><i>c</i></sub>=<i>M</i>ω<sup>2</sup><i>R</i>, exerted on it by the string. The reaction force exerted by the rotating mass <i>M</i>, the so-called centrifugal force, is <i>M</i>ω<sup>2</sup><i>R</i> in a direction away from the center of rotation.
Industry:Science
A field concerned with the development of technologies to control and manipulate the growth and activities of selected biological agents to create desirable products and economic gain or to prevent economic loss. In addition to bacteria and yeasts, animal and plant cell cultures are now used to produce sophisticated products such as monoclonal antibodies, immunomodulating compounds, and complex plant metabolites.
Industry:Science
A field in the science of conservation that is concerned with the application of ecological principles to restoring degraded, derelict, or fragmented ecosystems. The primary goal of restoration ecology (also known as ecological restoration) is to return a community or ecosystem to a condition similar in ecological structure, function, or both, to that existing prior to site disturbance or degradation.
Industry:Science
A field of engineering concerned with the development and application of robots, and computer systems for their control, sensory feedback, and information processing. There are many types of robotic systems, including robotic manipulators, robotic hands, mobile robots, walking robots, aids for disabled persons, telerobots, and microelectromechanical systems.
Industry:Science
A field of engineering dealing with ways and means by which conditions of processes are brought to and maintained at desired values, and undesirable conditions are avoided as much as possible. In general, a process is understood to mean any system where material and energy streams are made to interact and to transform each other. Examples are the generation of steam in a boiler; the separation of crude oil by fractional distillation into gas, gasoline, kerosine, gas-oil, and residue; the sintering of iron ore particles into pellets; the polymerization of propylene molecules for the manufacture of polypropylene; the incineration of waste; and the roasting of green coffee beans.
Industry:Science
A field of study concerned with the interaction of electromagnetic radiation and matter in which the matter responds in a nonlinear manner to the incident radiation fields. The nonlinear response can result in intensity-dependent variation of the propagation characteristics of the radiation fields or in the creation of radiation fields that propagate at new frequencies or in new directions. Nonlinear effects can take place in solids, liquids, gases, and plasmas, and may involve one or more electromagnetic fields as well as internal excitations of the medium. Most of the work done in the field has made use of the high powers available from lasers. The wavelength range of interest generally extends from the far-infrared to the vacuum ultraviolet, but some nonlinear interactions have been observed at wavelengths extending from the microwave to the x-ray ranges.
Industry:Science
A field or generic term for natural hydrous iron oxides, the most common phase being the mineral goethite, α-FeO(OH). Limonite occurs as a low-temperature mixture of phases and includes the so-called bog iron ores. It is the characteristic brown stain which coats rocks containing sulfide ores, such as pyrite and pyrrhotite, in the zone of weathering of these ores referred to as a gossan. A vast list of pseudonyms, such as limnite, hypoxanthite, and xanthosiderite, plague the earlier literature. Limonite is most commonly a mixture of greater or lesser fractions of goethite, hematite, ferric oxyhydroxide colloids, clays, and manganese oxides. It is formed by biogenic or inorganic precipitation in bog, spring, lacustrine, or marine deposits.
Industry:Science
A field that combines the disciplines of biology and engineering mechanics and utilizes the tools of physics, mathematics, and engineering to quantitatively describe the properties of biological materials. One of its basic properties is embodied in so-called constitutive laws, which fundamentally describe the properties of constituents, independent of size or geometry, and specifically how a material deforms in response to applied forces. For most inert materials, measurement of the forces and deformations is straightforward by means of commercially available devices or sensors that can be attached to a test specimen. Many materials, ranging from steel to rubber, have linear constitutive laws, with the proportionality constant (elastic modulus) between the deformation and applied forces providing a simple index to distinguish the soft rubber from the stiff steel.
Industry:Science
A field that encompasses the investigation of the chemical composition of the Earth, other planets, and indeed the solar system and universe as a whole, as well as the chemical processes that occur within them. The discipline is large and very important because basic knowledge about the chemical processes involved is critical for understanding subjects as diverse as the formation of economically valuable ore deposits, safe disposal of toxic wastes, and variations in the Earth's climate.
Industry:Science
A film one molecule thick. It is often referred to as a monolayer. Films that form at surfaces or interfaces are of special importance. Such films may reduce friction, wear, or corrosion, or may stabilize emulsions, foams, and solid dispersions. Thin films on water surfaces can reduce evaporation losses, though the spreading of thin films on such surfaces can represent a serious environmental problem. In some instances, the film spreads by itself and is essentially insoluble in the substrate (an insoluble monolayer). In other cases, the film molecules have a low substrate solubility and concentrate at the surface (a Gibbs monolayer).
Industry:Science
