number density


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number density

[′nəm·bər ‚den·səd·ē]
(physics)
The number of particles per unit volume.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
We will also learn about the formation and early evolution of supermassive black holes, by comparing the measured number density and luminosity distribution with predictions from theoretical models," Yoshiki Matsuoka, a former Princeton researcher now at Ehime University in Japan who led the study, said.
The model is capable of reproducing experimental results of conversion, and the evolution of number density of particles.
The higher hardness is derived from a higher number density of atoms per unit volume, and higher toughness is derived from its amorphous structure.
For example [5], the micrographs in Figure 2 show the very high number density of creep voids developed in the HAZ of a stub to header weld.
The median raindrops have the largest number density, which contribute most to rain-rate; the number density and width of median raindrops increase with the increasing of rain-rate, and the raw capture DSD is obviously lower than the real DSD because of the unsteady capture probability, which takes on a nonuniform step downward trend, especially in the light rainfall and rainstorm; there is no significant discrepancy between the inversed DSDs from interval 1, interval 2, interval 3, and interval 4, which agree well with real DSD.
To verify the physical models and the CFD calculation schemes used in this paper, temperature distributions along the stagnation streamline and peak electron number density along the body are calculated for a blunt cone using the same parameters of the RAM-C II flight model [27].
Then, the jet's contribution to high energy [gamma]-ray emission is mostly dependent on its internal turbulence (turbulence here means spatial number density of proton accelerating shocks randomly oriented) [7].
The precursors mostly determine the soot particle number density through the nucleation process, that is, conversion of PAH gas to particles.
where n is particle number density, [n.sub.0] is the reference particle number density as a criteria of the fluid volume, which is defined by the initial particle number density in a regular distribution of particles, and [DELTA]t is the time increment of computation.
"Given the rate of stars falling onto black holes and the number density of black holes in the nearby universe, we calculated how many such transients Pan-STARRS should have detected over a period of operation of 3.5 years.
Where [I.sub.ij] and [[lambda].sub.ij] is the intensity and wavelength corresponds to transition from i to j, h is the Planck's constant, n number density of emitting species, c is the speed of light, U(T) partition function, [A.sub.ij] is the transition probability between level i and j.