REAL Density, Solids, Pigment solids. Cost, Pigment... [Pg.60]

However, one feature of the HF potential is that it is not a local potential. In the case of perfect data (i.e. zero experimental error), the fitted orbitals obtained are no longer Kohn-Sham orbitals, as they would have been if a local potential (for example, the local exchange approximation [27]) had been used. Since the fitted orbitals can be described as orbitals which minimise the HF energy and are constrained produce the real density , they are obviously quite closely related to the Kohn-Sham orbitals, which are orbitals which minimise the kinetic energy and produce the real density . In fact, Levy [16] has already considered these kind of orbitals within the context of hybrid density functional theories. [Pg.267]

With this approximation, the evaluation of the Coulomb term scales as N2M, in contrast to the standard way, which scales as N4 (N and M are the number of primitive functions in the orbital and density basis sets, respectively). The expansion coefficients of the electronic density in Eq. (8) are chosen such as to minimize the error in the Coulomb term arising from the difference between the real density and the fitted density [25],... [Pg.186]

The real density of coke is obtained when the particle size of the specimen is smaller than 75 mm. The real density (or the particle size) exerts a direct influence on the physical and chemical properties of the carbon and graphite products that are manufactured from the coke. [Pg.299]

In the test method (ASTM D2638), a sample is dried and ground to pass a 75-mm screen. The mass of the volume is determined directly, and the volume derived by the volume of helium displaced when the sample is introduced into a helium pycnometer. The ratio of the mass of the sample to the volume is reported as the real density. [Pg.299]

Combining terms with m — —l and m = l, gives the expansion in terms of the real spherical harmonic functions, which we will use to evaluate the Fourier transform of the real density functions ... [Pg.68]

The electrical resistivity of a petroleum coke having a real density of 1.39 was 9 X 106... [Pg.284]

Before petroleum coke can be used for making anodes for making aluminum, it must be calcined. This converts it from an electrical insulator into an electric conductor. At the same time its real density is raised to about 2.0 (17). During the calcination, losses of 15 to 30% by weight are sustained (25). The volatile content is reduced to less than 0.5% (17). Calcination may be done in shaft kilns, electric calciners (17) y or rotary kilns (87). In rotary kilns, temperatures up to 2700° F. may be used (37). Care must be taken in the electric calciners not to graphitize the coke otherwise the thermal conductivity of the product will be too high for anode use (17). [Pg.286]

Benham and Matthews (Ref 20) used the Gumey approach to compute flyer plate velocities of plates propelled by a light-initiated expl. They present a curve that appears to indicate that y/2E is a function of c, the expl real density.. [Pg.219]

Mean Particle Size (jim) Pt % Dispersion Surface Area (m2/g) Real Density (g/ml) Apparent Density (g/ml) Pore Volume (ml/g) Mean Pore Radius (A)... [Pg.179]

If hv increases to higher values (which is easily achieved in a synchrotron), /) shifts above the density of states into the range corresponding to entirely free electrons in vacuum, which can be considered as a continuum. Thus, if hv, and consequently Ef increase, the UPS spectrum approaches the true density of states of the metal. Of course, XPS also images the real density of state, but at lower resolution, due to the broader line width of the X-ray source. [Pg.67]

The types of graphitic carbon powders which primarily are applied as conductive additive belong to the family of highly crystalline graphite materials. These graphite materials show real densities of 2.24-2.27 g cm-3 (values based on the xylene density according to DIN 12 797 and DIN 51 901-X) and average interlayer distances of c/2 = 0.3354-0.3360 nm.55... [Pg.269]

Petroleum coke calcining is a process whereby green or raw petroleum coke is thermally upgraded to remove associated moisture and volatile combustible matter (VCM) and to otherwise improve critical physical properties, e.g., electrical conductivity and real density (JL ) The calcining process is essentially a time-temperature function the most important variables to control are heating rate, VCM to air ratio and final temperature. To attain the calcined coke properties necessary for its end use by the amorphous carbon or graphite industries, the coke must be heat treated to temperatures of 1200-1350°C (2200-2500°F), or higher, to refine its crystalline structure. [Pg.180]

See also in sourсe #XX -- [ Pg.460 ]

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