Productivity classification definition

In this chapter, the classification of industrial products for transportation under present DOT regulations and disposal classifications under RCRA will be discussed. A brief discussion of pesticide classification under FIFRA is also presented. It must be kept in mind that regulations are a living set of rules which are frequently modified by amendments, deletions and new definitions. Thus, while an attempt has been made to present the subject of product classification in a manner that will be affected as little as possible by the process of regulatory change, this is clearly not entirely possible. The reader must be aware of this fact and of his responsibility for keeping abreast of any new developments in this field. 

Source. Ref. 51. (The terms and definitions taken from ISO 1109 1975 Refractory Products, Classification Table, are reproduced with the permission of the International Organization for Standardization, ISO. These standards can be obtained from any ISO member and from the web site of the ISO Central Secretariat at the following address www.iso.org. Copyright remains with ISO.)... 

Classification is by definition used preponderantly in the treatment of raw materials. However, these raw materials find their way into chemical processing per se and thus become of interest to the chemical engineer, particularly when the products to be treated reaci better when of a defined cleanliness, size, gravity, or moisture content. 

Agricultural crops, effect of acidification, 52 Agricultural productivity, biocides-net productivity relationship, 307-308 Agricultural technologies, changes, 311,313 Airborne contaminants, description, 135 Airborne pollutant, definition, 135 Air pollutants, classifications, 66 Air pollution effects, 166,167r scope, 21-22 sources, 165-166 state, 4... 

The vast number of thermodynamically possible reactions obtained by permuting oxidants and reductants within the scope of this review present major problems of classification and selection. To only a limited extent is the modernity or detail of a paper indicative of its relevance, some of the definitive papers having been published before 1950. Discussion has been concentrated, therefore, at points where a kinetic investigation of a reaction has resulted in a real advance in our understanding both of its mechanism and of those of related reactions, and work which has been more of a confirmatory nature will not receive comparable consideration. Detailed reference to products, spectra, etc. will be made only when the kinetics produce real ambiguities. 

The chemical and physical properties of the polymers obtained by these alternate methods are identical, except insofar as they are affected by differences in molecular weight. In order to avoid the confusion which would result if classification of the products were to be based on the method of synthesis actually employed in each case, it has been proposed that the substance be referred to as a condensation polymer in such instances, irrespective of whether a condensation or an addition polymerization process was used in its preparation. The cyclic compound is after all a condensation product of one or more bifunctional compounds, and in this sense the linear polymer obtained from the cyclic intermediate can be regarded as the polymeric derivative of the bifunctional monomer(s). Furthermore, each of the polymers listed in Table III may be degraded to bifunctional monomers differing in composition from the structural unit, although such degradation of polyethylene oxide and the polythioether may be difficult. Apart from the demands of any particular definition, it is clearly desirable to include all of these substances among the condensation... 

The challenge of this chapter then is to clarify the nature of chemical products, give the basic definitions related to a chemical product and see how these definitions can be useful for the classification, study and design of chemical products. 

The definitions in the first section of this chapter can be useful in many ways for design, especially in the stages of search, physical prototype and manufacture. For example, the classifications of Figure 15.4-1 can help to establish the order in which different decisions related to the product must be made. For example, the procedure for a product of type 5, can start by identifying the components that contribute to the properties that are not complementary with the environment. In a second stage, we identify the most appropriate components for the complementary properties with the environment. 

The definitions and classifications can help in the same way to each specific stage in Figure 15.4-3. In the stage of search, for example, the definitions can help to identify in a better way the necessities and the required properties. For example, if it is desired to improve any property that is complementary to the environment, the identification of the niche or niches may help to identify the appropriate ingredient, or to include a pretreatment or a post-treatment which modifies the niche characteristics, before or after using a product. This is what... 

Based on these definitions and descriptions, classification of chemical products can be performed in a more scientific way, without ambiguities and/or overlap. These classifications should help to understand the nature of some products and to organize their study. This preliminary approach is expected to give examples and/or methodologies of design using these principles in the near future. 

In terms of waste definition, there are three basic approaches (as it pertains to petroleum, petroleum products, and nonpetroleum chemicals) to defining petroleum or a petroleum product as hazardous (1) a qualitative description of the waste by origin, type, and constituents (2) classification by characteristics based on testing procedures and (3) classification as a result of the concentraUon of specific chemical substances. 

Production network design by definition needs to include distribution decisions. For the purpose of this classification a model is considered to include distribution network design only if at least one distribution echelon (warehouses, distribution centers, etc.) is explicitly modeled. The term "distribution center" is not defined uniformly in literature (cf. Higginson and Bookbinder 2005). Here, distribution centers where a production step takes place are considered to be a production echelon whereas those performing picking or packaging operations are considered to be a distribution echelon. 

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