Effect of crystal structure

An overview of the effect of crystal structure on color application properties of organic pigments was published [7]. 

This section will discuss some important concepts from coloristic practice and the optical properties of pigmented systems. Space considerations permit a treatment of only the most vital concepts. The reader must consult the literature for further details and accounts of special problems [1], A review on the effect of crystal structure on color application properties was published [2],... 

Fuerstenau (1980) found that sulphide minerals are naturally floatable in the absence of oxygen. Yoon (1981) ever attributed the natural floatability of some sulphide minerals to their very low solubility. Finkelstein et al. (1975) considered that the natural floatability of sulphide minerals are due to the formation of elemental sulphur and related to the thickness of formation of elemental sulphur at the surface. Some authors reported that the hydrophobic entity in collectorless flotation of sulphide minerals were the metal-deficient poly sulphide (Buckley et al., 1985). No matter whichever mechanism, investigators increasingly concluded that most sulphide minerals are not naturally floatable and floated only under some suitable redox environment. Some authors considered that the natural floatability of sulphide minerals was restricted to some special sulphide minerals such as molybdenite, stibnite, orpiment etc. owing to the effects of crystal structure and the collectorless floatability of most sulphide minerals could be classified into self-induced and sulphur-induced floatability (Trahar, 1984 Heyes and Trahar, 1984 Hayes et al., 1987 Wang et al., 1991b, c Hu et al, 2000). 

Zheng YF (1993a) Oxygen isotope fractionation in Si02 and Al2Si05 polymorphs effect of crystal structure. Eur J Miner 5 651-658... 

Chemical crystallography is the study of the principles of chemistry behind crystals and their use in deseribing strueture-property relations in solids. The prineiples that govern the assembly of crystal and glass structures are deseribed, models of many of the teehnologically important erystal struetures are studied, and the effect of crystal structure on the various fundamental meehanisms responsible for many physical properties are discussed. This new book presents and reviews data on the coordination chemistry of several metal complexes with dipicolinic acid and the erystal structure of some antimalarial metal complexes. 

Other experiments showed that both selectivity and product distribution could be drastically affected by changes in the electrode potentials [70]. Similarly, surface roughness and pretreatment were also factors affecting methane production [41]. In addition, when the effect of crystal structure was examined, the rate of methane production in a C02-saturated 0.5 M KHC03 electrolyte was shown to be highest on Cu(lll), followed by Cu(110) and Cu(100) [41]. 

One may expect that future work on the electrochemistry of diamond should take two paths, namely, an extensive investigation (search for new processes and applications of the carbon allotropes in the electrochemical science and engineering) and intensive one (elucidation of the reaction mechanisms, revealing the effects of crystal structure and semiconductor properties on the electrochemical behavior of diamond and related materials). It is expected that better insight into these effects will result in the development of standard procedures for thin-film-electrodes growth, their characterization, and surface preparation. 

Hunger, K. (1999). The effect of crystal structure on color application properties of organic pigments. Rev. Prog. Coloration and Related Topics, 29,11-84. [258,259, 268]... 

Surface area is also directly proportional to the dissolution rate of a solute. Particle size reduction is another common and often efficient means by which to achieve higher levels of drug in solution at earlier time points.As particle size decreases, the surface area per unit volume of solute increases and consequently more drug is exposed to the solvent. Also, as particle size decreases the surface molecules are of higher free energy which increases dissolution. And finally, the processing of solid material can often lead to crystal defects within a particle or surface area where crystallinity is lost (amorphous), both of which can increase the apparent solubility. Mosharraf et al. have demonstrated the effect of crystal structure disorder on solubility and dissolution rate. ... 

The deamminations and dehydrations of ammonium salts, which are generally reversible processes, are often complicated by the occurrence of solid-phase transformations, sublimation (for example NH4CIO4 [2]) and/or melting. It is, therefore, difficult to determine experimentally the effects of crystal structure, defects and surface properties on the chemical changes occurring. 

Simon, B., Flandrois, S., Fevrier-Bouvier, A., and Biensan, P. (1998). Hexagonal vs rhombohedral graphite the effect of crystal structure on electrochemical intercalation of lithium ions. Mol. Cryst. Liq. Cryst., 310, 333—40. 

The Effect of Crystal Structure in Transition Metal Sulfide... 

In the preceding part of this paper the predominance of the "periodic effect on HDS by sulfide catalysts was described. Because periodicity dominates, crystal structure is of secondary importance. However, in this section we briefly examine the effect of crystal structure on the catalytic properties of the transition metal sulfides. In the case of catalysts such as M0S2 and WS2, the most industrially important catalysts, the effect of crystal structure is quite pronounced. An understanding of the effect of crystal structure in these catalysts is essential to optimizing their catalytic properties for a given application. 

The effect of crystal structure may be investigated by preparing catalysts, as described above, at various temperatures which assures a set of catalysts having variable surface areas, pore size distributions, and crystallinity. Measuring the catalytic activity as a function of these physical properties will help to define the role of crystal structure for the particular transition metal sulfide. In general, the HDS is poorly correlated to N2 BET surface area. This non-correlation can be most easily seen by preparing a... 

Some Effects of Crystal Structure on Production of Radicals in Irradiated Organic Crystals... 

We report here some observations on irradiated metal salts of acetic acid which suggest that changing the crystal structure by changing the number of molecules of water of crystallization may lead to quite different stable radicals at 77 °K. It is hoped that further studies of the effects of crystal structure on the nature of the free radicals obtained on irradiation may aid in choosing conditions under which a given desired radical might be stable. 

Healy, T.W., Herring, A.P. and Fuerstenau, D.W. (1 966) The effect of crystal structure on the surface properties of a series of manganese dioxides. Journal of Colloid and Interface Science 21, 435-444. 

Effect of crystal structure on the composition of the primary gaseous products Qualitative 10... 

Effects of Crystal Structure and Physical Properties on the Release of Chiral Drugs... 

Chance, B. Ravilly, A. Rumen. N.J. Reaction kinetics of a crystalline hemoprotein An effect of crystal structure on reactivity of fei-rimyoglobin. J. Mol. Biol. 1966. 17. 525-534. 

Herranz T, Garcia S, Martmez-Hueita MV et al (2012) Elecbooxidation of CO and methanol on well-characterized cartxm supported PtxSn electrodes. Effect of crystal structure. Int J Hydrogen Energy 37 7109-7118... 

Factors known to influence bond length include the valency state of the P atom (X.), its coordination schane (a), the electronegativities of the remaining substituents, the interaction of surrounding molecules and effects of crystal structure. 

Nishida, H. and Tokiwa, Y. (1993) Effects of higher-order structure of poly(3-hydroxybiityrate) on its biodegradation. II. effects of crystal structure on microbial degradation. /. Environmental Polymer Degradation, 1, 65-80. 

Figure 2 also illustrates the effect of crystal structure, by the higher values over the range of temperatures (910°C to 1400°C) at which the FCC gamma phase exists. Solubility in the delta phase is an extrapolation of the alpha values indicating similar behavior for these BCC phases. In the liquid, solubility is much higher than in the solid. This plot is based upon measurements taken above 400°C (750°F). 

The effect of crystal structure of activated carbon on methanation. As mentioned above, the initial methanation temperature of activated carbon derived from coal is more than 500°C and above 600°C for graphite. Although low purity of activated carbon derived from coal, they have strong resist-methanation ability, which indicates the effect of micro-crystal structure on methanation is very significant. The main reason of methanation of activated carbon is the unsaturated dangling bonds of edge carbon atoms, which is confirmed from the crystal structure of carbon materials (Fig. 6.70). ... 

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