Size distribution oxidation factor

The erosion of graphite in nozzle appHcations is a result of both chemical and mechanical factors. Changes in temperature, pressure, or fuel-oxidizing ratio markedly affect erosion rates. Graphite properties affecting its resistance to erosion include density, porosity, and pore size distribution... 

The economics of some mines frequentiy depend heavily on the revenues derived from leaching the waste to recover additional copper. This waste material, which has to be removed to uncover the ore, may be hauled to specially constmeted dumps, where the sulfides, the most common form of copper mineral, are oxidized and the leach solution can contact the waste material uniformly. Economics sometimes precludes optimization of dumps for leaching operations because of such factors as compaction, size distribution, and terrain (16). 

Xin and co-workers modified the alkaline EG synthesis method by heating the metal hydroxides or oxides colloidal particles in EG or EG/water mixture in the presence of carbon supports, for preparing various metal and alloy nanoclusters supported on carbon [20-24]. It was found that the ratio of water to EG in the reaction media was a key factor influencing the average size and size distribution of metal nanoparticles supported on the carbon supports. As shown in Table 2, in the preparation of multiwalled carbon nanotube-supported Pt catalysts... 

The surface concentration, size distribution and other properties of metal nanoparticles formed in a dark on the surface of the inert wide-band-gap semiconducting oxides under contact, photocatalytic, or photoelectrochemical deposition depend substantially on the concentration, bulk distribution, and energy characteristics of donor defects in the initial semiconductor substrate. As a rule, the necessary condition for the formation of the smallest-sized particles in the highest surface concentration is the maximum shift of the surface potential of semiconducting matrix from its equilibrium value during metal deposition. This is part of the reason for the experimentally observed fact that the particles formed in the condition of photocatalytic deposition are characterized by less average size and cover superior portion of surface than those obtained under cathodic deposition, all other factors being equal. 

Besides higher unit costs, in both initial investment and replacement, another factor limiting inorganic membranes from wider usage is the control of their pore size distributions. Recent advances, however, such as the sol-gel process and anodic oxidation have started to be implemented in commercial production and have made significant impacts on the current and future market shares of the inorganic membranes. 

The rate of nucleation depends on the mobility of Ni atoms, which is a function of both temperature and the nature of the substrate. Oxides that reduce with difficulty, such as Ni[Al2j04, result in tower mobilities. The relative rates of reactions (6.9) and (6,10) determine the subsequent crystal lite size and distribution. Fast reduction and slow nucleation give narrow distributions of small crystallites. Similar rates lead to broad distributions, and rapid nucleation to large crystallites. For a given substrate, temperature is the determining factor. Figure 6,21 shows the resulting crystallite size distribution for reduction of Ni/SiOi at 400 C and The lower... 

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