- 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 member of a class of organic compounds composed of carbon, hydrogen, and oxygen. They can be considered as hydroxyl derivatives of hydrocarbons produced by the replacement of one or more hydrogens by one or more hydroxyl (–OH) groups.
Industry:Science
A member of a class of organic compounds with any of several dozen functional groups containing sulfur (S) and often also oxygen (O), nitrogen (N), hydrogen (H), as well as other elements.
Industry:Science
A member of a class of proteins containing hemes as prosthetic groups that catalyze oxidation/reduction reactions. Cytochromes are distinct from other heme-containing proteins, such as myoglobin and hemoglobin, which function in the binding and/or transport of molecular oxygen; catalase, which eliminates hydrogen peroxide from cells; and peroxidases, which use hydrogen peroxide to oxidize various substrates.
Industry:Science
A member of a class of subatomic particles called baryons, which exists in four electric charge states and has a total spin of <i>J</i> = 3/√<span style="border-top:1px solid black;">2</span>. In the underlying quark model, the delta resonance (Δ) consists of three quarks whose intrinsic spins of ½ are lined up in the same direction. The Δ is closely related to the more familiar nucleon constituents of atomic nuclei, the neutrons (<i>n</i>) and protons (<i>p</i>).
Industry:Science
A member of a group of organic compounds which can be considered as derived from ammonia by replacement of one or more hydrogens by organic radicals. Generally amines are bases of widely varying strengths, but a few which are acidic are known.
Industry:Science
A member of one of several groups of objects that are composed almost entirely of natural glass formed from the melting and rapid cooling of terrestrial rocks by the energy accompanying impacts of large extraterrestrial bodies. Tektites are dark brown to green, show laminar to highly contorted flow structure on weathered surfaces and in thin slices, are brittle with excellent conchoidal fracture, and occur in masses ranging to as much as tens of kilograms but are mostly much smaller to microscopic in size. The shapes of tektites are those of common fluid splash and rotational forms including drops, spheres, and dumbbells, unless they have been abraded together with surface gravels. A few tektites have shapes that are caused by two different heating events: the impact that melted the parent rock to form the glass, and a second event apparently due to reentry aerodynamic heating.
Industry:Science
A member of the calcite-type car-bonates having the formula MgCO<sub>3</sub>. It forms dolomite (CaMg(CO<sub>3</sub>)<sub>2</sub>) with calcite (CaCO<sub>3</sub>) in the system CaCO<sub>3</sub>–MgCO<sub>3</sub>. Pure magnesite is not common in nature because there exists a complete series of solid solutions between MgCO<sub>3</sub> and FeCO<sub>3</sub>, which is constantly present in magnesite in its natural occurrence.
Industry:Science
A member of the camel family (Camelidae) found only in South America. The llama is an artiodactyl, or even-toed ungulate, with two toes on each foot. The upper lip is cleft and prehensile. The animal has a long neck, and attains a maximum length of less than 8 ft (2.4 m) and a maximum weight of nearly 300 lb (135 kg; see <b>illus.</b>). A single young is born after a gestation period of about 11 months. The maximum life-span is about 20 years. Like other members of the family, the llama is herbivorous. It has 36 teeth with the dental formula I 1/3 C 1/1 Pm 3/3 M 3/3. These animals lack a gallbladder. Many interesting crosses have occurred among the different breeds in South America (see <b>table</b>).
Industry:Science
A member of the class of curves that are intersections of a plane with a cone of revolution. The ellipse is obtained when the plane cuts all the elements of one nappe, and does not go through the apex. In the <b>illustration</b>, denote the distance between two points, <i>F</i>, <i>F</i><sup>′</sup> of a plane by 2<i>c</i>, <i>c</i> > 0, and let 2<i>a</i> be a constant, with <i>a</i> > <i>c</i>. The ellipse with foci <i>F</i> and <i>F</i><sup>′</sup> and major axis 2<i>a</i> is the locus of points <i>P</i> of the plane such that <i>PF</i> + <i>PF</i><sup>′</sup> = 2<i>a</i>, where <i>PF</i> denotes the distance of <i>P</i> and <i>F</i>. This suggests the following construction of an ellipse. Put pins at <i>F</i> and <i>F</i><sup>′</sup>, and slip over them a loop of thread of length 2<i>a</i> + 2<i>c</i>, pulling the thread taut with a pencil. If the pencil is moved, keeping the thread taut, its point traces an ellipse. Another way to construct an ellipse is to drill a hole in a stick (at any point other than the midpoint) and move the stick so that its ends slide along two mutually perpendicular lines. The point of a pencil inserted in the hole will trace an ellipse. Limiting forms of the ellipse are (1) a circle, as the two foci approach coincidence, and (2) the segment <i>FF</i><sup>′</sup>, as <i>c</i> approaches <i>a</i>. If a circle is projected orthogonally on a plane not parallel to the plane of the circle, an ellipse is obtained, and every ellipse may be so obtained. Lines joining the foci to a point <i>P</i> of an ellipse make equal angles with the tangent to the ellipse at <i>P</i>, and consequently light or sound that emanates from one focus is reflected to the other focus. This property is used in construction of “whispering galleries.”
Industry:Science
A member of the class of curves that are intersections of a plane with a cone of revolution. It is obtained (see <b>illustration</b>) when the cutting plane is parallel to an element of the cone.
Industry:Science
