mass concentration

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concentration

 [kon″sen-tra´shun]
1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.
3. intense mental focus.
hydrogen ion concentration see hydrogen ion concentration.
mass concentration the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/l).
mean corpuscular hemoglobin concentration (MCHC) the average hemoglobin concentration in erythrocytes, conventionally expressed in “per cent,” meaning grams per deciliter of red blood cells, obtained by dividing the blood hemoglobin concentration (in g/dl) by the hematocrit (in l/l): MCHC = Hb/Hct.
minimal alveolar concentration (MAC) the concentration of anesthetic that at a pressure of 1 atmosphere produces immobility in 50 per cent of subjects exposed to a noxious stimulus.
minimal bactericidal concentration (MBC) the lowest concentration of a given antibiotic required to kill a specific organism.
minimal inhibitory concentration (MIC) the lowest concentration of a given antibiotic that inhibits the growth of a specific organism.
molar concentration the concentration of a substance expressed in terms of molarity.
concentration test a test of renal function based on the patient's ability to concentrate urine; see also fishberg concentration test.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

mass concentration

The mass of a constituent in a solution divided by the volume of the mixture.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

mass concentration

?
The amount of matter of any material divided by its volume. In the metric system, ? is defined in kilograms per liter (kg/L). See: substance concentration; molar concentration
See also: concentration
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
NASA's 2012 GRAIL mission gave new insight into mascons. A Purdue University study concluded that large asteroid impacts carved huge craters, liquified the interiors, and drew in surrounding material that melted and congealed there.
Lunar gravity solutions, especially the acceleration profile of mascons, were obtained from Apollo flight data until the mid-1970s [2226].
Sjogren, "Mascons: lunar mass concentrations," Science, vol.
"GRAIL data confirm that lunar mascons were generated when large asteroids or comets impacted the ancient moon, when its interior was much hotter than it is now," said Jay Melosh, a GRAIL co-investigator at Purdue University in West Lafayette, Ind., and lead author of the paper.
"We believe the data from GRAIL show how the moon's light crust and dense mantle combined with the shock of a large impact to create the distinctive pattern of density anomalies that we recognize as mascons," he asserted.
The origin of lunar mascons has been a mystery in planetary science since their discovery in 1968 by a team at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
A red ring and blue mascon "bull's-eye" defines a third small basin on which Copernicus later appeared.
Throughout the first half of 1999, the neutron spectrometer will refine the locations of polar ice deposits, while the Doppler gravity experiment will attempt to resolve the mascons well enough to let geophysicists deduce their true origin.
For example, topographic profiles across the large near-side basins show that the mare basalts on their floors are only thick enough to account for about 20 percent of the associated mascons. And some basins exhibit similar gravity "highs" even though little mare material appears inside them.
Some computer models suggest that the combined stresses from this and the mascon could produce the strange radial ridge patterns we see.
The ancient Australe basin has no mascon, which might indicate that the Moon's crust was so warm at this early stage in lunar history that the basin's upraised mantle subsided before the crust cooled.
Computations by Jet Propulsion Laboratory geophysicists suggest that the mascon can be explained by a dense layer 10 to 20 km thick somewhere between 3 and 50 km deep.