Powder analysis, physical characteristics

The powders of zeolites of various trademarks are used to produce petroleum-refining catalysts. In this connection, it is very important to have complete information concerning not only chemical composition and distribution of impurity elements, but also shape, surface, stmcture and sizes of particles. It allows a more detailed analysis of the physical-chemical characteristics of catalysts, affecting their activity at different stages of technological process. One prospective for solving these tasks is X-ray microanalysis with an electron probe (EPMA). 

Referring to Tab. 11.1 (Chapter 11), to be able to evaluate a particulate solid or the mixtures of particles and/or powders, the chemical and, particularly, the physical properties of this material must be known. A description of all the methods and procedures that are available today to completely characterize particulate solids and determine all the quality attributes that are necessary for a meaningful determination of their behavior under different process conditions is a book project in itself Therefore, in the context of this book, only a few will be mentioned. Those selected represent relatively new laboratory equipment that combines the analysis of different powder characteristics in one piece of equipment and/or improve the gathering of data, that is of particular interest for agglomeration. 

Drug evidence, like all evidence in forensic science, has characteristics that can be used to describe eind categorize it. The first division used by forensic scientists reflects the type of drug analysis needed. For physical evidence submitted to a crime laboratory (pUls, powders, plant matter, paraphernalia, precursors, or related evidence), the central forensic question is "What controlled substimce is present " Secondary questions relate to how much and to what else might be there, such as adulterants, diluents, and contaminants. Exhaustive analysis may be used to further categorize drug samples into... 

The first distinguishing characteristic noted for heroin samples is their physical state and appearance, ranging from dry, white powders to black resins. Particle size analysis has been employed for purposes of differentiation. Some... 

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