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matrix
matrix in mathematics, a rectangular array of elements (e.g., numbers) considered as a single entity. A matrix is distinguished by the number of rows and columns it contains. The matrix
is a 2×3 (read "2 by 3" ) matrix, because it contains 2 rows and 3 columns. A matrix having the same ...
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composite material
composite material or composite, any material made from at least two discrete substances, such as concrete. Many materials are produced as composites, such as the fiberglass -reinforced plastics used for automobile bodies and boat hulls, but the term usually is used to describe any of various ...
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cytoplasm
cytoplasm The material surrounding the nucleus of a cell. It consists of a matrix (see cytosol) in which the cell's organelles are suspended. The cytoplasm may be differentiated into dense outer ectoplasm, which is concerned primarily with cell movement, and less dense endoplasm, which contains most...
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Babbitt metal
Babbitt metal an antifriction metal first produced by Isaac Babbitt in 1839. In present-day usage the term is applied to a whole class of silver-white bearing metals, or "white metals." These alloys usually consist of relatively hard crystals embedded in a softer matrix, a structure important f...
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printer
printer computer output device that reproduces data on paper or another medium. Impact printers use a mechanical hammering device to produce each character. A formed character printer forces metal or plastic characters against an inked ribbon to produce a sharp image on paper; the characters ma...
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determinant
determinant a polynomial expression that is inherent in the entries of a square matrix . The size n of the square matrix, as determined from the number of entries in any row or column, is called the order of the determinant. If the entry in row i and column j is denoted as aij , then, for ...
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Mitochondrion
Mitochondrion
Mitochondria (singular mitochondrion) are abundant organelles present in nearly all eukaryotic cells . The main function of mitochondria is to produce adenosine triphosphate (ATP), the cellular energy source. Mitochondria are believed to be the evolutionary result of early anaerobi...
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keratin
keratin , any one of a class of fibrous protein molecules that serve as structural units for various living tissues. The keratins are the major protein components of hair, wool, nails, horn, hoofs, and the quills of feathers. These proteins generally contain large quantities of the sulfur-containi...
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seal
seal stamp made from a die or matrix of metal, a gem, or other hard substance that yields an impression on wax or other soft substance. The use of seals is very ancient, examples of great antiquity occurring in China, Egypt, Greece, Rome, and other places. The most common form was the seal ring, of...
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Werner Heisenberg
Werner Heisenberg , 1901-76, German physicist. One of the founders of the quantum theory, he is best known for his uncertainty principle , or indeterminacy principle, which states that it is impossible to determine with arbitrarily high accuracy both the position and momentum (essentially velocity)...
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