Critical milling factors

Color is another critical quality factor. It is subjectively evaluated by inspectors in a representative rice sample that has been previously milled using laboratory equipment. The color varies from desirable white to undesirable dark gray (Table 2.5). One of the most common off-colors is pink or rose, which results from the contamination of rice with red wild rice. The red pigments present in the aleu-rone-contaminated white kernels gives them a pink coloration. Parboiled rice is classified according to light or dark coloration. The hydrothermal process enhances color formation. 

IAEA/AL/095 1996). Both methods were suitable, but needed to be repeated several times to produce the small particle size that was required. The particle size reduction, e.g. of IAEA-395 from a median size of 30 pm to 3.5 pm, improved the homogeneity of elements. Sampling constants (the minimum mass that can be used to achieve a random error of i % at the 65 % confidence level) improved from a factor of 1.2 for Sc, up to a factor of 800 for Au. The average improvement was about a factor of 2-10. (Ni Bangfa et al. 1996). From these initial experiences, it is dear that preparation of reference materials is critical with respect to the final particle size distribution, which should exhibit a low maximum (<50 pm) and a narrow range in particle sizes. Milling techniques to meet such criteria are available today, and materials that show intrinsic uniformity are particularly suitable to achieve the desired properties. 

The synthesis of carbonyls by the reaction of Ni, Fe or Mo with carbon monoxide is possible under low-temperature and low-pressure conditions. The apparent activation energy is reduced under milling conditions. The difference between non-acti-vated solid, pretreated solid and simultaneous reaction and milling is depicted in Fig. 14.15 [10]. At normal temperatures, a distinct decrease in activation energy and frequency factor can be seen this higher reactivity is derived from a high dislocation density. Below a critical temperature, the solid alters the breakage behavior from... 

The critical factors involved with obtaining the desired grind with the cone mill are ... 

According to simple theories, substances should behave the same when all variables are suitably scaled and the critical parameters are the most common scaling factors chosen. Figure 4b shows Mills et al. [137] -25.5° C data, which is equivalent to oxygen at 30° C when scaling by the critical temperatures. The N2 sound speeds are reducedusing critical pressures and densities. 

A critical factor in the analysis of yeast biodiversity concerns the methodology used to identify the microbes present. A recent comprehensive review has appeared on this topic (Bokufich, Bamforth, Mills, 2012). Often, yeasts are cultured prior to identification by subsequent physiological or molecular analyses. The act of growing yeast colonies in isolation prior to characterization and taxonomic identification may result... 

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