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the Earth and this information alone requires that there be a concentration of mass towards the centre of the globe. Additional information is to be found in the frequencies of the graver normal modes of the Earth which are sensitive to density through self-gravitation effects induced in deformation".
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Several models for density gradient have been built on the basis of PREM but they acknowledge that the "distribution of density as a function of position within the Earth is much less well constrained than the seismic velocities. The primary information comes from the mass and moment of inertia of
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A popular model for the density gradient of Earth is one given by the
Preliminary Reference Earth Model (PREM) that is based on the observed oscillations of the planet and the travel times of thousands of
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In the life sciences, a special technique called density gradient separation is used for isolating and purifying cells, viruses and subcellular particles. Variations of this include
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Also in the field of
Computational Fluid Dynamics, Density gradient is used to observe the acoustic waves, shock waves or expansion waves in the flow field.
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In the study of population, the density gradient can refer to the change in density in an urban area from the center to the periphery.
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122:, requires the framework of density gradients in which elements and compounds then interact. The existence of a
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405:"The Spatial Distribution of Population in 48 World Cities: Implications for Economies in Transition"
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A steep density gradient in a body of water can have the effect of trapping energy and preventing
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250:"Effects of sill processes and tidal forcing on exchange in eastern Long Island Sound"
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Proceedings of the
National Academy of Sciences of the United States of America
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system at the core of the earth is one theory by reason of density gradient.
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observes the density gradient of air as it interacts with aircraft.
219:"CFI-Shadowgraph/Schliren Photography for Aerodynamic Applications"
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188:"Chicago Wilderness Journal, Volume 1 - Number 1 - November, 2003"
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The understanding of what is at the centre of the earth, the
74:. In the case of salt water, sharp gradients can lead to
163:"Non-Destructive Testing Resource Center - Glossary"
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379:"On the density distribution within the Earth"
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290:"Substructure of the inner core of the Earth"
356:Physics of the Earth and Planetary Interiors
264:"GE Healthcare Density Gradient Separation"
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358:. Elsevier Scientific Publishing Company
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110:involves density gradient separation.
23:over an area. The term is used in the
106:. A blood donation technique called
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349:"Preliminary reference Earth model"
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347:Dziewonski, Adam; Anderson, Don.
70:, such a gradient is employed in
104:Sucrose gradient centrifugation
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27:to describe varying density of
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124:fast breeder nuclear reactor
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100:Differential centrifugation
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19:is a spatial variation in
96:Isopycnic centrifugation
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31:, but can apply to any
383:Geophysics Journal Int
288:Herndon, J.M. (1996).
315:10.1073/pnas.93.2.646
53:Schlieren photography
35:whose density can be
300:(2). PNAS: 646–648.
306:1996PNAS...93..646H
82:. This is called a
385:. Oxford Academics
377:Kennett, B. L. N.
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446:Spatial gradient
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47:In the study of
25:natural sciences
17:Density gradient
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419:. Retrieved
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195:the original
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167:the original
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43:Aerodynamics
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72:solar ponds
435:Categories
421:2006-12-09
274:2006-12-09
235:2006-12-09
204:2006-12-09
173:2006-12-09
150:References
120:earth core
114:Geophysics
68:convection
49:supersonic
84:Halocline
334:11607625
108:Pheresis
80:salinity
51:flight,
37:measured
33:quantity
441:Density
389:30 June
362:30 June
302:Bibcode
90:Biology
21:density
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102:, and
29:matter
415:(PDF)
408:(PDF)
352:(PDF)
325:40105
229:(PDF)
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62:Water
391:2020
364:2020
330:PMID
320:PMC
310:doi
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