Density A property of matter representing

Density a property of matter representing the mass per unit volume. 

Denaturation the breaking down of the three-dimensional structure of a protein resulting in the loss of its function. (22.6) Denitrification the return of nitrogen from decomposed matter to the atmosphere by bacteria that change nitrates to nitrogen gas. (20.2) Density a property of matter representing the mass per unit volume. (1.8)... 

The concept of potential energy in mechanics is one example of a scalar field, defined by a simple number that represents a single function of space and time. Other examples include the displacement of a string or a membrane from equilibrium the density, pressure and temperature of a fluid electromagnetic, electrochemical, gravitational and chemical potentials. All of these fields have the property of invariance under a transformation of space coordinates. The numerical value of the field at a point is the same, no matter how or in what form the coordinates of the point are expressed. 

Table III gives the physical and chemical properties of the M. oleifera oil. Some of the properties of the oil depend on the extraction medium. The M oleifera oil is liquid at room temperature and pale-yellow in colour. Electronic nose analysis shows that it has a flavor similar to that of peanut oil. The melting point estimated by differential scanning calorimetry is 19°C (15). The chemical properties of the oil depicted in Table III below are amongst the most important properties that determines the present condition of the oil. Free fatty acid content is a valuable measure of oil quality. The iodine value is the measure of the degree of unsaturation of the oil. The unsaponifiable matter represents other lipid- associated substances like, sterols, fat soluble vitamins, hydrocarbons and pigments. The density, iodine value, viscosity, smoke point and the colour of Moringa oil depends on the method of extraction, while the refractive index does not. Varietal differences are significant in all physical characteristics apart from refractive index and density (2). The heating profile of the M. oleifera seed oil using the differential scanning calorimetry (DSC) conventional scan rate shows that there is one major peak B and, two small shoulder peaks A and C...

The examples in Section 9.1 illustrate that it would be desirable to base a population analysis on properties of the wave function or electron density itsell and not on the basis set chosen for representing the wave function. The electron density is the square of the wave function integrated over Aeiec - 1 coordinates (it does not matter which coordinates since the electrons are indistinguishable). 

In addition to its chanical properties, the efficient use of a coal also requires a knowledge of its physical properties, such as its density (which is dependent on a combination of rank and mineral matter content), hardness, and grindability (both related to coal composition and rank). Other properties include its abrasion index (derived mainly from coarse-grained quartz) and the particle size distribution. Float-sink testing may also be included with the analysis process. This involves separating the (crushed) coal into different density fractions as a basis for assessing its response to coal preparation processes. Float-sink techniques may also be used to provide a coal sample that represents the expected end product of a preparation plant, in order to assess the quality of the coal that will actually be sold or used rather than the in situ or ROM material represented by an untreated (raw) coal sample. 

Unlike other well-defined areas of NMR, LR-NMR applications cover all states of matter (solid state, solution, etc.), and all possible areas of chemistry in industry and research. Probe head size assures representative sampling for measuring inhomogeneous materials. The technique requires calibration only once, albeit with separate calibrations for different problems e.g. for powder and granulate of the same material). The unique discrimination power of the technique is based on the discrimination in mobility between various components of a sample e.g. oil in rubber, solubles, rubber content, dispersion of fillers) or between different physical structures of a molecule e.g. crystallinity, density, tacticity, copolymer content, melt properties, tensile strength, etc.). Phase analysis by nuclear spin relaxation time measurements rests upon the assumption that each phase present will give a unique relaxation time which can be found by a multiexponential fit of a relaxation... 

Phase transitions in a material can be classified as first order and continuous (second order). At a first-order phase transition, we observe a discontinuity of some physical property representative of the degree of order in the system. For example, this could be material density or a calculated measure of order in the material (i.e., an order parameter). If we measure this parameter across the phase boundary, there will be a step, or discontinuity, at the transition point. An example of a typical first-order phase transition is ice melting. At the transition point, the density of the material abruptly changes as we go from ice to liquid water. First-order transitions also have a measureable latent heat. Some phase transitions can be described as weakly first order. In this case, the enthalpy change associated with that transition is very small. This is often true of phase transitions in soft matter systems. As a result, the enthalpy change may be difficult to measure, thus making the phase change difficult to detect by thermal properties alone. 

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