In-place density

Compacted density In-place density of compacted bituminous paving mixtures... 

For porous solids such as coal, there are five different density measurements true density, apparent density, particle density, bulk density, and in-place density. The true density of coal is the mass divided by the volume occupied by the actual, pore-free solid in coal. However, determining mass of coal may be deemed as being rather straightforward, but determining volume presents some difficulties. Volume, as the word pertains to a solid, cannot be expressed universally in a simple definition. Indeed, the method used to determine volume experimentally, and subsequently, the density, must be one that applies measurement rules consistent with the adopted definition. 

The in-place density (bank density) of coal is the means by which coal in the seam can be expressed as tons per acre per foot of seam thickness and/or tons per square mile per foot of seam thickness (Table 6.4). The in-place density must be determined on water-saturated samples (Berkowitz, 1979) to accommodate the equilibrium moisture (Chapter 3) that exists under the in-place (or seam) conditions. 

Compaction. The field compaction studies confirmed earlier laboratory studies regarding the effect of compactive effort, moisture addition, and aging on density and strength. Shown in Figure 4 is the relationship of compactive effort on the densities of retorted shale. At least three in-place density measurements were made in each layer. Results show that densities averaging 1400 kg/m3 (about 95 lb/cu. ft.) can be achieved. 

The in-place density of coal is the means by which coal in the seam can be expressed as tons per acre per foot of seam thickness and/or tons per square mile per foot of seam thickness (Table 9.3). 

The test method involves obtaining a relatively intact soil sample by driving a thin-walled cylinder and the subsequent activities for the determination of in-place density. When sampling or in situ density is required at depth, test Method D 1587 should be used. 

AASHTO T 310. 2013. In-place density and moisture content of soil ami soil-aggregate by nuclear methods (shallow depth). Washington, DC American Association of State Highway and Transportation Officials. 

Chang G., Q. Xu, and J. Rutledge. 2012. Intelligent Compaction Quality Assurance for In-Place Density Acceptance Experiment Plan for the Asphalt IC Demonstration in Utah. FHWA-RD-12. Springfield, VA National Technical Information Service. 

Hydrocarbons are of a lower density than formation water. Thus, if no mechanism is in place to stop their upward migration they will eventually seep to the surface. On seabed surveys in some offshore areas we can detect crater like features ( pock marks ) which also bear witness to the escape of oil and gas to the surface. It is assumed that throughout the geologic past vast quantities of hydrocarbons have been lost in this manner from sedimentary basins. 

The collection of representative reservoir fluid samples is important in order to establish the PVT properties - phase envelope, bubble point, Rg, B, and the physical properties - composition, density, viscosity. These values are used to determine the initial volumes of fluid in place in stock tank volumes, the flow properties of the fluid both in the reservoir and through the surface facilities, and to identify any components which may require special treatment, such as sulphur compounds. 

Molality is used in thermodynamic calculations where a temperature independent unit of concentration is needed. Molarity, formality and normality are based on the volume of solution in which the solute is dissolved. Since density is a temperature dependent property a solution s volume, and thus its molar, formal and normal concentrations, will change as a function of its temperature. By using the solvent s mass in place of its volume, the resulting concentration becomes independent of temperature. 

Normalised fiber mechanical properties are expressed in terms of unit linear density. For example, in describing the action of a load on a fiber in a tensile test, units of N/tex or gram force per denier (gpd) are generally used. If this is done, the term tenacity should be used in place of stress. The tme units of stress are force per unit cross-sectional area, and the term stress should be reserved for those instances where the proper units are used. 

Particles in the gradient may be separated on the basis of sedimentation rate a sample introduced at the top of the preformed gradient setties according to density and si2e of particles, but the mn is terminated before the heaviest particles reach the bottom of the tube. If the density of all the particles ties within the range of the density limits of the gradient, and the mn is not terminated until all particles have reached an equiUbtium position in the density field, equiUbtium separation takes place. The steepness of the gradient can be varied to match the breadth of particle densities in the sample. 

No specific mixing rules have been tested for predicting compressibility factors for denned organie mixtures. However, the Lydersen method using pseudocritical properties as defined in Eqs. (2-80), (2-81), and (2-82) in place of true critical properties will give a reasonable estimate of the compressibihty faclor and hence the vapor density. 

The preceding equations, which have assumed that both the air and the water vapor benave as ideal gases, are sufficiently accurate for most engineering calculations. If it is desired to remove the restriction that water vapor oehave as an ideal gas, the aclual density ratio should be used in place of the molecular-weight ratio in Eqs. (12-5) and (12-6). 

Density The weight of a given volume of exchange material, backwashed and in place in the column. 

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