Systematic classifications

UJPAC nomenclature standardized systematic classification include stcrcochcmistr) widespread unambiguous allow reconstruction extensive nomenclarurc rules altcrnalivc names are allow-ed complicated names... 

Ferrites can be classified according to crystal stmcture, ie, cubic vs hexagonal, or magnetic behavior, ie, soft vs hard ferrites. A systematic classification as well as some appHcations ate given in Table 1 (see also Magnetic materials, bulk Magnetic materials, thin film). 

The European Union (EU) has a systematic classification of white sugars, shown in Table 10. Codex JUimentarius also has issued specifications for white sugars (17). The EU standards are widely used throughout Eastern Europe and Asia. Other countries, eg, Brazd and the People s RepubHc of China, have their own domestic specifications, which are also appHed to imports. 

BL Sibanda, TL Blundell, JM Thornton. Conformation of (I-hairpms m protein stractures A systematic classification with applications to modelling by homology, electron density fitting and protein engineering. J Mol Biol 206 759-777, 1989. 

With these definitions in mind, a systematic classification has been made. The various types of embrittlement found in refineries and petrochemical plant equipment, susceptible steels, basic causes, and common remedies are listed in the accompanying table. 

Systematic Classification of Enzymes According to the Enzyme Commission ... 

No single criterion has been recognized as constituting a satisfactory basis for the systematic classification of the kinetics of solid-phase reactions (Chapt. 1, Sect. 3). A classification based on the anion is preferred here since it is this constituent which undergoes breakdown in most reactions of interest and proposed reaction mechanisms for substances containing a common anion often include similar features. 

Classification of Enzymes. A systematic classification and nomenclature has been established by the Commission on Enzymes of the International Union of Biochemistry (6), which divides enzymes into six general groups ... 

E.H. Hurst s overview introduced several themes pursued by other chemical industry speakers. The Dow Chemical Company s E.H. Blair analyzed the problem of setting priorities for testing the 55,000 existing chemicals listed in the TSCA inventory for their effects on health and the environment. Resources for such testing are not unlimited. A systematic classification was made of these substances by production volume. The 9.5% of these substances which account for 99.9% of reported production were divided further into categories such as organic, inorganic, and polymeric. 

Carbocations are central to hydrocarbon chemistry (/). Much of this chemistry is based on acid catalysis, which leads to generation of positive ions of carbon. The resulting intermediates are classified as carbenium and carbonium ions, as proposed by Olah (2-4). Carbonium ions are the penta- or higher coordinate carbocations that maintain 8 valence electrons via 2-electron/3-center bonding, quite different from carbenium ions that possess only 6 valence electrons. Figure 1 shows a systematic classification of carbocations. 

As we have seen, many nineteenth-century chemists minimized the dependence of their field on hypothetical reasoning and stressed its basis in empirical laws, rational analogy, and systematic classification. Nonetheless, chemists used and debated among themselves the validity and implications of several fundamental chemical theories. 

Kripyakevich, P.I. (1963) A systematic classification of types of intermetallic structures J. Struct. Chem., 4. 

Appendix B consists of a systematic classification and review of conceptual models (physical models) in the context of PBC technology and the three-step model. The overall aim is to present a systematic overview of the complex and the interdisciplinary physical models in the field of PBC. A second objective is to point out the practicability of developing an all-round bed model or CFSD (computational fluid-solid dynamics) code that can simulate thermochemical conversion process of an arbitrary conversion system. The idea of a CFSD code is analogue to the user-friendly CFD (computational fluid dynamics) codes on the market, which are very all-round and successful in simulating different kinds of fluid mechanic processes. A third objective of this appendix is to present interesting research topics in the field of packed-bed combustion in general and thermochemical conversion of biofuels in particular. 

In addition, at each step the four-figure EC number (see p. 88) for the enzyme responsible for a reaction is given in italics. The enzyme name and its systematic classification in the system used by the Enzyme Catalogue are available in the following annotated enzyme list (pp. 420-430), in which all of the enzymes mentioned in this book are listed according to their EC number. The book s index is helpful when looking for a specific enzyme in the text. 

Johann Wolfgang Dobereiner, 1780-1849, Professor of chemistry at Jena. His discovery of the triads was an important step toward the systematic classification of the chemical elements He wrote many books and papers on general and pharmaceutical chemistry, mineral waters, the manufacture of vinegar, and the use of platinum as a catalyst, The original of this portrait is in the City Museum at Jena. 

For simplicity, a systematic classification of solid surfaces by heat of immersion values in a single liquid is desirable. Il in (53) predicted on theoretical grounds a decrease in the heat of wetting with increase in the size of the cation in salts or oxides. However, Il in and Kiselev (54) found that the decrease in the heat of immersion from SrSO< to PbS04 to BaS04 predicted by theory is not observed. Heat data for the immersion of a variety of solids in water are listed in Table VII. Here, too, the changes in heat values are not systematic. 

In 1893 Werner founded his new constitutional formula for inorganic compounds, applied the theory to the systematic classification of the chromi-ammines, and found that all the chromi-ammines which had been investigated could be fitted in to his system of classification. Since then the chemistry of the chromi-ammines has been further developed hv Werner, Pfeiffer, and many others relationships have been traced between chromi-ammines, complex salts, and chromic salt hydrates, and numerous cases of isomerism have been discovered in this series of ammines. 

Higher polychromates (e.g., Cr302o)can be isolated in yields up to 45%, under appropriate conditions 48). A systematic classification of Cr— bond lengths has been developed for polychromate anions (Fig. 4), and these bond types have been correlated with the degree of polymerization 48). 

The rapid evolution and the multifarious activity in the field of phosphorus chemistry is well illustrated by the proposal (Dupart)332 of a new systematic classification of free and coordinated phosphorus compounds to complete the systems proposed by Wolf333 and by Perkins et a/.334. In this new system, a code number NFE(NPL)D could be used to describe the compound, in which NFE would be the number of free electrons, N the number of valence shell electrons, L the number of ligands and D the number of electron doublets donated or accepted, which would be negative if the P atom acted as a donor (a Lewis base), or positive if P acted as an acceptor (a Lewis acid). 

Soil classification has been oriented to soil properties in recent years, but still is tempered with concepts of soil genesis, with external associations, and with the use of the soil. The first systematic classification was by Dokuchaiev in Russia in 1882, Based upon field and laboratory characteristics, soils were grouped into three categories—normal soils of the dry-land vegetative zones and moors, transitional soils of washed or dry land sediments and abnormal soils. The system involved properties of the soil with external associations of climate and vegetation. Later, an associate (Sibirtsev) renamed the highest classes zonal intrazonal, and azonal. 

Table 2.1 Partial Outline of the Systematic Classification of Enzymes...

In the last section we briefly described how new NLO crystals in the borate were developed through a systematic classification and calculation of microscopic second-order susceptibilities and... 

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