Specific surface area factors affecting

Factors affecting the rate at which AljOj is supplied include its content in the clinker, its distribution among the clinker phases and especially the amount present in the aluminate, the specific surface area of the ground clinker, the reactivities of the aluminate and ferrite, and the microstructure of the clinker particles, or, more specifically, the areas of surface composed of aluminate and ferrite phases and the manner in which these phases are... 

It is most often prepared by acid hydrolysis of sodium silicate followed by emulsification in an alcohol water mixture and subsequent condensation to give solid silica gel. This is then washed and dried for use as HPLC column packing. The exact conditions under which these procedures are carried out (e.g. pH, catalysts, temperature) will affect the properties of the resulting material. The most important qualities with regard to the chromatographic performance of the gel are the average particle size, the particle shape, the specific surface area and the pore size. Other factors which are also important are the pH of the gel surface, the number of active silanol groups and the presence of metal ions. 

Thus, the present analysis of the dependence of the specific surface area on the composition of samples shows that the area of co-precipitated porous materials is higher than that of each of the components only in the case when the pH values of precipitation of hydroxides in the mixture are different. This condition is a part of the mechanism of formation of the structure of co-precipitated materials with the most extensive porosity. Of course, under the action of the various factors affecting the process of structure formation, the absolute value of Ssp can both increase and decrease, but the general trend in Ssp remains unchanged and persists for all binary systems meeting the requirements listed above. 

Magnesium oxide may be applied as a powder or as a suspension in oil and it has found use in a wide range of coal and oil fired equipment [Locldin et al 1980], The chemical is an alkaline hygroscopic powder and it is usually one of the ingredients of many proprietary blends of combustion additives. It would appear that the origin of the magnesium oxide and the preparation technique influence its performance. Conditions within the combustion space will also affect its activity. The specific surface area of the additive will also represent a factor in its efficiency. 

The RH dependency of the first-order rate constant of aspirin decomposition in the CPG 170 mixture at 50°C is illustrated in Fig. 10. An anomalous linear relationship was obtained between the RH and the rate constants as the RH was raised, the rate constant decreased. Leeson and Mattocks [21] proposed the mechanism of aspirin decomposition in the solid state as follows. After the formation of a water layer on aspirin particles, aspirin was dissolved into the water layer. The aspirin then decomposed in the solution. In the crystalline state, the amount of adsorbed water increased at a high RH therefore, faster aspirin decomposition was observed. On the other hand, the stability of aspirin in the solid dispersed system was affected by many factors such as hygroscopicity of additives, pH on the surface, specific surface area, and dispersed state. El-Banna et al. [22] reported that the aspirin in the coprecipitated samples with povidone or urea had slightly higher degradation rates due to its increased water sorption ability. In the case of a urea solid dispersion. 

Carbon support could be another factor affecting catalytic activity. Jaouen et al. [51 ] studied the effect of carbon support on catalytic activity and found that die activity varied with the specific surface area, pore size distribution, and N or O content of the carbon support. 

We can see that when the stirring rate is increased so much that the specific surface area is increased Hvefold (assuming the mass transfer coefficient does not change much), the reaction time for reaching 99% conversion of B would go down from 3300 to 2S(X) s. An increase in pressure would increase the solubility of A and reduce the reaction time accordingly. An increase in temperature would mainly affect the reaction rate constant, ff this were increased by a factor of 5, and the other variables were not changed, the Hatta number

still applicable. The necessary reaction time for 99% conversion of B would become 1460 s. When both the reaction rate constant and the specific surface area were increased by a factor of 5, the reaction time for 99% conversion of B would be only 660 s. 

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