Powders concentration-dependent

Microprobe studies of pack-chromised iron (Cr powder, alumina, CrCl, mixture) shows that the surface Cr concentration builds up with time to 95% in 20 h at 1 300 K ", and that the diffusion coefficient for Cr in a-phase is very concentration dependent. The growth of carbides during pack-chromising and during gas-vanadising have been studied. 

Irie H, Watanabe Y, Hasbimoto K (2003) Nitrogen-concentration dependence on pbotocatalytic activity of Xi02-X Nx powders. J Phys Chem B 107 5483-5486... 

Figure I. Reinforcement of silicone gums by carbon blacks (including nonrreinforcmg NR), silica powder (both surface-treated T and untreated NT), and titanium dioxide. The increase in modulus per unit dose and filler concentration depends on filler particle size.

Nitrogen-Concentration Dependence on Photocatalytic Activity of Ti2-xNx Powders. Samples prepared by annealing anatase Ti02 under NFL flow at 550-600 °C. 311... 

YBOsiEu vary with the synthetic route. The YBOaiEu powder synthesized through a sol-gel method exhibit three Eu sites identified by site selective excitation. The Eu concentration dependence of emission intensity and Eu luminescence decay from 300 to 15 K prove that the energy migration is phononassisted. (Boyer et al., 2003). 

As observed for the photoreduction of methyl orange [218] and the oxidative photodimerization of olefins [80] catalyzed by CdS powder, the dependence of rate on CdS concentration increases approximately linearly and reaches a plateau at about 3 g L. Surprisingly, in the same concentration range the ratio of addition to hydrodimer product (20a 21a) decreases from 2 to about 1. This can be rationalized by considering that the specific rate which is the measured rate divided by the amount of catalyst employed, decreases with increasing catalyst concentration (Figure 32). 

Concentration-Dependent Da in Powders. It has been assumed in the powder techniques discussed so far that Da does not depend upon intracrystalline concentration. For the dilute range of sorptions—e.g., where Henry s law is valid—this is correct. However, as already considered (Table III), over extended ranges in concentration Tiselius s results for water in a single crystal of heulandite showed strong concentration dependence. For powders, 2 methods may be mentioned. 

The conversion of liquid dairy streams into powders is an important processing operation in the dairy industry. The removal of water from a dairy stream during concentration and drying can influence the functional properties of the resultant powders. This depends on factors such as the composition of the stream to be dried, the type of driers used, and the conditions of drying. Both the physical characteristics of the powders (e.g., particle size, bulk density, occluded air) and their functional properties can be affected by drying (Tong, 2001). 

Let us now proceed with the discussion of the general trends of surfactant adsorption at solid surfaces. The most common method used to monitor adsorption phenomena in such systems is to study the concentration dependence of surfactant adsorption. In these studies solid surfaces with high specific surface areas, such as powders and highly porous adsorbents, are used. If the surface area of adsorbent, S), is not known, then the total amount of substance accumulated per unit weight of adsorbent, T, is determined. The latter can be established from the decrease in the concentration of adsorbing substance, Ac, in a solution of known volume, V, after adsorption equilibrium has been established, i.e. ... 

H. Me, Y. Watanabe, K. Hashimoto, Nitrogen-concentration dependence on photocatalytic, activity of Ti02 xNx powders , Journal of Physical Chemistry B, 107(23), 5483-5486, (2003). 

The number of electron paramagnetic resonance (EPR) investigations made on amorphous alloys is rather limited. Bates et al. (1971) investigated amorphous Gd, j.Agj. alloys prepared by dropping a powdered-mixture of Gd and Ag on to a molybdenum filament having a temperature of 2000°C. Condensation of the vapour was allowed to take place on substrates either kept at room temperature or cooled with liquid helium or liquid nitrogen. For various compositions the authors studied the temperature dependence of the linewidth. Curie temperatures were estimated from the position of the minima occurring in the linewidth-versus-temperature plots. Bates et al. found that the concentration dependence of the Curie temperature in Gd, sharp minimum (7 = 45 K) near x — 0.10 in alloys deposited on... 

Vitl] Preparation from powders annealing at 400-490°C for 1500 h microstmcture analysis Vickers hardness electrical resistance. Concentration dependence of H and p temperature dependence of p partial isothermal section at 400°C in the vicinity of FeNi3 partial vertical section Fc3Ni-Co below 500°C. 

Due to the ionic equilibrium of the species in the CUSO4-H2SO4-H2O system (the most often employed electrolytes for the electrodepositiOTi of copper are sulfate ones), the shape of powder particles depends on CUSO4 and H2SO4 concentrations [32-34]. For a constant H2SO4 concentration, the ion concentration decreases with increasing Cu concentration that is manifested by the change of shape of powder particles from the cauliflower-like to dendritic (Mies. 

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