In the → superheterodyne technique, the electronic component that lowers the frequency of the input signal and combines it with the signal coming from the → local oscillator to produce the → intermediate frequency signal. The lowered frequency, when amplified, has little chance to escape back into the antenna and produce feedback. Moreover, it is easier to make efficient amplifiers, filters, and other components for lower frequencies.
Agent noun from → mix.
Verbal noun of → mix.
Fr.: longueur de mélange
In a → turbulent flow, the average distance traveled by a → convective cell before it dissolves into its surroundings and deposits its energy. The mixing length is of the order of the → pressure scale height (HP), l = αHP, where α is the → mixing length parameter. See also → mixing length theory.
mixing length parameter
pârâmun-e derâzâ-ye âmizeš
Fr.: paramètre de la longueur de mémange
In the → mixing length theory, a parameter, α, that relates the → mixing length, l, to the → pressure scale height: α = l/HP. It is usually supposed that α is of order unity. Changes in α correspond to variations in the efficiency of the → convection, hence the transfer of heat.
mixing length theory (MLT)
negare-ye derâzâ-ye âmizeš
Fr.: théorie de la longueur de mélange
A theory dealing with heat transport by → turbulence which includes an elementary treatment of → convection. The central idea is that an unbalanced → buoyancy force drives a → convective cell to move through a distance, called the → mixing length, before the cell dissolves and joins the ambient medium. In this theory an adjustable → mixing length parameter α is used. The theory, originally due to L. Prandtl (1925), was first applied to the Sun by L. Biermann (1932, Z. Astrophys. 5, 117).
Fr.: processus de mélange
A process whereby → angular momentum and chemical species are transported from layer to layer within a star. The main mixing processes include: → convection, → overshooting, → rotation, and → turbulence. The extent to which the interiors of stars are mixed strongly influences their evolution, age, chemical content, and the relationship between their internal and surface → chemical abundances.
Fr.:rapport de mélange
Mass of water vapor per mass of dry air; expressed as grams per kilogram. → humidity
An aggregate of two or more substances that are not chemically combined with each other.
M.E., from L. mixtura "a mixing," from mixtus, → mix.
Âmizé, from âmiz present stem of âmixtan, → mix.
Mizar (ζ Ursae Majoris)
A star of visual magnitude 2.3 in the constellation → Ursa Major, which is the second star from the end of the → Big Dipper's handle. It forms a naked-eye double with → Alcor, lying at an angular separation of about 12 minutes of arc. Mizar is resolved into a 14''.4 → binary star (denoted A and B) with a probable period of thousands of years. Mizar A is a nearly equal-mass, → double-lined spectroscopic binary with period 20.54 days and → eccentricity of 0.53. The two components of Mizar A (denoted Aa and Ab) are both about 35 times as luminous as the Sun, and revolve around each other in about 20 days. Similarly, Mizar B is a → spectroscopic binary with a period of 175.57 days and an eccentricity of 0.46. Recent results suggest that Alcor is actually a binary and apparently → gravitationally bound to the Mizar system. This would make the Mizar-Alcor system a probable → sextuplet, lying at about 78 → light-years from Sun and the second closest such multiple known, after → Castor (Mamajek et al., 2010, AJ 139, 919).
Mizar, from Ar. al-Mi'zar (
Fr.: système MKS
The system of → MKS units.
Fr.: unités MKS
yâdsepâr (#), yâdsepârik
1) (adj.) Assisting or intended to assist the
From Gk. mnemonikos "of or pertaining to memory," from mnemon "remembering, mindful," from mnasthai "remember," from PIE base *men- "to think;" cf. Pers. man-, -mân, minu, → idea.
Yâdsepâr, stem of Yâdsepârdan "memorize," from yâd "remembrance, recollection, memory" (Mid.Pers. ayâd) + sepârdan, sepor- "to yield, give, hand over" (Mid.Pers. abespâr- "to hand over, entrust;" cf. O.N. spara, O.H.G. sparon, O.E. sparian, E. spare); yâdsepârik, → mnemonics.
Something capable of assisting one's memory. The process or technique of improving the memory.
1) Capable of moving or being moved readily.
From M.Fr. mobile, from L. mobilis "movable, easy to move; loose, not firm," contraction of *movibilis, from movere "to → move."
Miyâvâ verval adj. and agent noun from miyâvidan, → move.
Of or relating to mode, manner, or form.
The quality or state of being → modal.
1) Physics: Any of the distinct patterns of oscillation that a
given periodically varying system can have.
Mode, from Fr. mode, from L. modus "measure, rhythm, song, manner," from PIE base *med- "to measure, limit, judge, advise;" cf. L. meditari "to think or reflect upon, consider;" Av. mad- "to measure out, apportion, allot;" Gk. medein "to rule;" O.E. metan "to measure out."
Tarz "manner, mode," Arabicized as
1) (n.) model, tarzâl; 2) (v.) model sâxtan, tarzâlidan
Fr.: 1) modèle; 2) modéliser
1a) A mathematical representation of a process, system, or object
developed to understand its behavior or to make predictions. The
representation always involves certain simplifications and
assumptions. See also → theory,
1) Model, from Fr. modèle.
Tarzâl, from tarz, → mode + -âl,