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Crystallization factors affecting

Batch crystallization factors affecting purity of recovered crystals, 85-99... [Pg.409]

Factors Affecting the Surface Energies and Surface Tensions of Actual Crystals... [Pg.271]

Adsorption Kinetics. In zeoHte adsorption processes the adsorbates migrate into the zeoHte crystals. First, transport must occur between crystals contained in a compact or peUet, and second, diffusion must occur within the crystals. Diffusion coefficients are measured by various methods, including the measurement of adsorption rates and the deterniination of jump times as derived from nmr results. Factors affecting kinetics and diffusion include channel geometry and dimensions molecular size, shape, and polarity zeoHte cation distribution and charge temperature adsorbate concentration impurity molecules and crystal-surface defects. [Pg.449]

Why do we get differences in crystal shape or habit This may be a matter of directional rates of growth. Factors affecting directional rates will then affect the habit. Directional rates of growth can be illustrated with a relatively simple crystal structure, that of sodium chloride. [Pg.61]

Strain hardening effect, 20 224 Straining efficiency, 77 340 Strain rate, 73 473 Strain recovery rate (Rr), in testing shape-memory polymers, 22 361 Strain sensors, 77 150, 151-152 Strain tensor, for noncentrosymmetry pont group crystals, 77 93-94 Strain versus time curve factors affecting, 73 473 material and microstructure effect on, 73 473-474... [Pg.889]

Pilati, F., Toselli, M., Messori, M., Manzoni, C., Turturro, A. E. and Gat-tiglia, E. G., On specific factors affecting the crystallization of PET the role of carboxyl terminal groups and residual catalysts on the crystallization rate, Polymer, 38, 4469 (1997). [Pg.559]

AIChESymp. Ser. (a) 65 (1969) no. 95, Crystallization from solutions and melts (b) 67 (1971) no. 110, Factors affecting size distribution (c) 68 (1972) no. 121, Crystallization from solutions Nucleation phenomena in growing crystal systems (d) 72 (1976) no. 153, Analysis and design of crystallisation processes (e) 76 (1980) no. 193, Design, control and analysis of crystallisation processes (f) 78 (1982) no. 215, Nucleation, growth and impurity effects in crystallisation process engineering (g) 80 (1984) no. 240, Advances in crystallisation from solutions. [Pg.893]

Hult et al. [36] have described semi-crystalline hyperbranched aliphatic polyesters where the crystallinity was induced by attachment of long alkyl chains as end groups. The crystallization was affected by several factors such as length of the end groups and the molecular weight of the hyperbranched polyester. The crystallization was proposed as being either intra- or intermolecular depending on the size of the hyperbranched polyester onto which the alkyl chains were attached. [Pg.19]

We have also seen (Sec. VI,A) that the position of the Fermi level on the surface of the crystal ,+ is determined, other conditions being equal, by its position inside the crystal e +. An increase of e + entails an increase of ,+, and a decrease of a decrease of e.+. We are thus led to the conclusion that the factors which shift the Fermi level in the bulk of the crystal, i.e., which affect the electrical conductivity, will also shift the Fermi level on the surface (in the same direction) i.e., they will affect the catalytic activity. Furthermore we come to the conclusion that the factors directly displacing the Fermi level on the surface without affecting its position in the bulk (i.e., the factors affecting the degree of bending of the bands) will also affect both the electrical conductivity and the catalytic activity simultaneously. [Pg.235]

Factors Affecting the Purity of L-Isoleucine Recovered by Batch Crystallization... [Pg.85]

We have now proposed fluidized bed type process, which can be applied to wastewater, containing from 2 to 23 mg/jg phosphate as P. This report reveals fundamental studies on factors affecting phosphate removal and crystallization rate in the fluidized bed process. [Pg.355]

In this experiment, tap water with added phosphate was used as influent. Concentration of phosphate was adjusted to an adequate range from 2 to 23 mg/jg. Calcium chloride and sodium hydroxide solution were added to maintain calcium concentration from 70 to 100 mg/jg and pH of the effluent from 9.0 to 9.5. Using this equipment, we performed experiments to obtain efficiency of phosphate removal, relationship between phosphate concentration, and crystallization rate and factors affecting phoshate removal. [Pg.358]

Factors that affect the growth of protein crystals also affect the growth of protein-DNA cocrystals. These factors include the nature of the buffering system, pH, ionic strength, temperature, concentration and nature of precipitant, and concentration of the complex (McPherson, 1990). Examples of crystallization... [Pg.235]

The electron diffraction study was complemented by an all-electron theoretical calculation of Lu, Wei, and Zunger (LWZ) (1992), using the local density approximation for the exchange and correlation terms in the Hamiltonian. They find agreement within x0.6% between the calculated and dynamic structure factor values for the lowest three reflections, (100), (110), and (111). But for (200), with sin 0/A = 0.3464 A-1, the discrepancy is as large as 1.7%. The discrepancy is attributed to insufficiently accurate knowledge of the temperature factors in this diatomic crystal, which affect the derivation of the X-ray structure factor from the electron diffraction measurement, as well as the calculation of the dynamic theoretical structure factors needed for the comparison with experiment. For the monoatomic Si crystal for which the B values are well known, the agreement is... [Pg.267]

Thus each band in a Raman spectrum represents the interaction of the incident light with a certain atomic vibrations. Atomic vibrations, in turn, are controlled by the sizes, valences and masses of the atomic species of which the sample is composed, the bond forces between these atoms, and the symmetry of their arrangement in the crystal structure. These factors affect not only the frequencies of atomic vibrations and the observed Raman shifts, respectively, but also the number of observed Raman bands, their relative intensities, their widths and their polarization. Therefore, Raman spectra are highly specific for a certain type of sample and can be used for the identification and structural characterization of unknowns. [Pg.261]

Most metals of practical importance are actually mixtures of two or more metals. Recall from Section 1.1.3 that these intimate mixtures of metals are called alloys, and when the bond between the metals is partially ionic, they are termed intermetallics. For the purposes of this chapter, and especially this section, we will not need to distinguish between an intermetallic and an alloy, except to note that when a compound is indicated on a phase diagram (e.g., CuAb), it indicates an intermetallic compound. We are concerned only with the thermodynamics that describe the intimate mixing of two species under equilibrium conditions. The factors affecting how two metal atoms mix has already been described in Section 1.1.3. Recall that the solubility of one element in another depends on the relative atomic radii, the electronegativity difference between the two elements, the similarity in crystal structures, and the valencies of the two elements. Thermodynamics does not yet allow us to translate these properties of atoms directly into free energies, but these factors are what contribute to the free energy of... [Pg.145]

It should be noted that there may be other possible factors affecting the normal growth rate of crystal faces. [Pg.70]


See other pages where Crystallization factors affecting is mentioned: [Pg.208]    [Pg.349]    [Pg.343]    [Pg.160]    [Pg.207]    [Pg.483]    [Pg.281]    [Pg.306]    [Pg.108]    [Pg.132]    [Pg.22]    [Pg.222]    [Pg.219]    [Pg.42]    [Pg.146]    [Pg.684]    [Pg.6]    [Pg.15]    [Pg.599]    [Pg.522]    [Pg.48]    [Pg.324]    [Pg.100]    [Pg.160]    [Pg.180]   
See also in sourсe #XX -- [ Pg.142 ]




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