Roughness processing conditions effect

A study was made of the effects of processing conditions and of blowing and nucleating agents and external lubricants on the apparent density, mechanical properties, linear thermal expansion coefficient and surface roughness of extruded cellular MDPE. Based on the results, recommendations were formulated for the properties of cellular MDPE pipes for the protection of light conducting cables. 16 refs. (Translation of Polimery, Tworzywa Wielkoczasteczkowe, No. 10, 1996, p.580). 

As well as influencing the rate of metal removal, the electrolytes also affect the quality of surface finish obtained in ECM, although other process conditions also have an effect. Depending on the metal being machined, some electrolytes leave an etched finish, caused by the non-specular reflection of light from crystal faces electrochemically dissolved at different rates. Sodium chloride electrolyte tends to produce an etched, matte finish with steels and nickel alloys a typical surface roughness would be about 1 pm Ra,... 

We first looked at the effect of varying the amount of hydrotreated material in an FCC feed blend from 0.0 to 96.7 vol%. Table 10 presents selected process conditions for the feed hydrotreater, which achieved 90% desulfurization and roughly 23 wt% conversion of vacuum gas oil to middle distillate and naphtha. 

A fundamental study was conducted to determine the parameters causing OP in rotational molded parts made from blended polymers. The study of the effects of process conditions showed that increasing heating time and temperature resulted in lower crystallinity and lower surface roughness. Some thermal degradation was also observed. 

The important beneficial effects that substrate roughness can bring were firmly established in the late sixties and early seventies, principally as a result of work in two areas. The first was associated with the electroless deposition of metals onto plastics such as ABS and polypropylene. In the process the plastics must be etched in a way which produces pits on a micrometre scale. Such a topography had been shown to be a necessary, but not sufficient condition for adequate adhesion [40]. 

Instead of the definition in Eq. (7-82), the selectivity is often written as log k,). Another way to consider a selectivity-reactivity relationship is to compare the relative effects of a series of substituents on a pair of reactions. This is what is done when Hammett plots are made for a pair of reactions and their p values are compared. The slope of an LEER is a function of the sensitivity of the process being correlated to structural or solvent changes. Thus, in a family of closely related LFERs, the one with the steepest slope is the most selective, and the one with the smallest slope is the least selective.Moreover, the intercept (or some arbitrarily selected abscissa value, usually log fco for fhe reference substituent) should be a measure of reactivity in each reaction series. Thus, a correlation should exist between the slopes (selectivity) and intercepts (reactivity) of a family of related LFERs. It has been suggested that the slopes and intercepts should be linearly related, but the conditions required for linearity are seldom met, and it is instead common to find only a rough correlation, indicative of normal selectivity-reactivity behavior. The Br nsted slopes, p, for the halogenation of a series of carbonyl compounds catalyzed by carboxylate ions show a smooth but nonlinear correlation with log... 

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