Antecedents

Quicklime and hydrated lime are reasonably stable compounds but not nearly as stable as their limestone antecedents. Chemically, quicklime is stable at any temperature, but it is extremely vulnerable to moisture. Even moisture in the air produces a destabilizing effect by air-slaking it into a hydrate. As a result, an active high calcium quicklime is a strong desiccant (qv). Probably hydrate is more stable than quicklime. Certainly hydrated lime is less perishable chemically because water does not alter its chemical composition. However, its strong affinity for carbon dioxide causes recarbonation. Dolomitic quicklime is less sensitive to slaking than high calcium quicklime, and dead-burned forms are completely stable under moisture-saturated conditions. 

The fire assay, the antecedents of which date to ancient Egypt, remains the most rehable method for the accurate quantitative determination of precious metals ia any mixture for concentrations from 5 ppm to 100%. A sample is folded iato silver-free lead foil cones, which are placed ia bone-ash cupels (cups) and heated to between 1000 and 1200°C to oxidize the noimoble metals. The oxides are then absorbed iato a bone-ash cupel (ca 99%) and a shiny, uniformly metaUic-colored bead remains. The bead is bmshed clean, roUed fiat, and treated with CP grade nitric acid to dissolve the silver. The presence of trace metals ia that solution is then determined by iastmmental techniques and the purity of the silver determined by difference. 

The fuzzy rulebase consists of a set of antecedent-consequent linguistic rules of the form... 

In this introductory chapter, I shall focus on the institutional beginnings of materials science, and materials engineering as well indeed, MSE became an accepted abbreviation at quite an early stage. Following an examination, in Chapter 2, of the earlier emergence of some related disciplines, the intellectual antecedents to and development of materials science in its early stages are treated in Chapter 3. The field made its first appearance in USA, and for a number of years developed only in that country. Its development elsewhere was delayed by at least a decade. 

The crowning development in MW determination was the invention of gel permeation chromatography, the antecedents of which began in 1952 and which was finally perfected by Moore (1964). A column is filled with pieces of cross-linked macroporous resin and a polymer solution (gel) is made to flow through the column. The polymer solute permeates the column more slowly when the molecules are small, and the distribution of molecules after a time is linked not only to the average MW but also, for the first time with these techniques, to the vital parameter of MW distribution. 

Intamiediate event A fault event that occurs because of one or more antecedent causes acting through logic gates. 

This is because many of the factors that have been shown to be the antecedents of major process accidents (e.g., poor procedures, inadequate training) are not usually under the control of the individual worker. The other approaches can also be applied to improving quality and productivity as well as process safety and can be readily integrated with engineering system safety techniques, as will be described in Chapters 4 and 5. 

In many accidents an important contributory cause is the fact that some change has occurred in what would otherwise be a stable system. The importance of change as an antecedent to accidents has lead to the development of a formal process to evaluate its effects. 

As long as the single control parameter, a, is less than or equal to four, the orbit of any point xq (0,1) remains bounded on the unit interval. Notice also, that like the Bernoulli map, this map is noninvertible there are two antecedents, Xn and x, for each point Xn+i- We now want to study the behavior of orbits as a function of the parameter a. That the behavior of this map strongly depends on the value of a is easily appreciated from figure 4.3, which shows sample evolutions for Q = 0.5, 2.5, 3.3, 4. 

Rounsaville BJ, Kosten TR, Kleber HD The antecedents and benefits of achieving abstinence in opioid addicts a2.5-year follow-up study. Am J Drug Alcohol Abuse 13 213-229, 1987... 

Voici un premier tableau qui indiquera bien I accroissement enorme de Taction toxique (ou anaphylaxie) par Teffet d injections antecedents. 

Yet, except for specific cases of acute poisoning (2,10, 11), and thus mostly of liver damage, there appears to be no reliably documented evidence that there are any cases of human cancer which can be unambiguously associated with an antecedent exposure to nitrosamines In the Western world (12). 

It is doubtful if any design is entirely novel. The antecedence of most designs can usually be easily traced. The first motor cars were clearly horse-drawn carriages without the horse and the development of the design of the modern car can be traced step by step from these early prototypes. In the chemical industry, modem distillation processes have developed from the ancient stills used for rectification of spirits and the packed columns used for gas absorption have developed from primitive, brushwood-packed towers. So, it is not often that a process designer is faced with the task of producing a design for a completely novel process or piece of equipment. 

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