Existing Nomenclature

The previous two chapters briefly described a number of two-polymer combinations polymer blends, blocks, grafts, and IPNs. A few somewhat more complicated systems were alluded to blends of a homopolymer with a block copolymer, or a mixture of a graft copolymer with one or both homopolymers. This chapter will explore some of the more complex (and interesting) structures, and provide a nomenclature scheme where one now does not exist.  

A good nomenclature scheme should accomplish two tasks (1) accurately name all of the existing known compositions and (2) provide a present and future base for making systematic information retrieval searches for known, missing, unsynthesized, or unrecognized materials included within the nomenclature scheme. 

Many simple polymer grafts and blocks already have precise names. For example, poly(butadiene-Z -styrene) represents the structure 

Similarly, poly(butadiene-g-styrene) is the name for the graft copolymer 

Because of the above considerations, Sperling and co-workers have evolved a tentative nomenclature scheme for polymer blends, blocks, graft copolymers, and IPNs. A few final points are in order. 

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It should be born in mind that this is a overall clay composition. When we compare the representations of a clay composition in both tables, we notice that chemists apply the existing nomenclature rules (chapter 3, Chemistry). Furthermore the above represention proves that clay contains a number of silicate minerals. The structure of these silicate minerals and of quartz was already discussed in the chapter on Geology and Minerology. In the next paragraph we will concentrate on a certain group of silicates, the so-called clay minerals. Without these minerals clay would not possess its specific clay properties. 

You know that the International Union of Pure and Applied Chemistry decided in 1922 to nominate a commission for the revision of the Geneva nomenclature of 1892, the latter having become inadequate for the rapidly increasing number of organic compounds. The aim of the commission was (1) to revise the Geneva nomenclature, (2) to complete it for the multitude of new compounds, and (3) to respect as much as possible the existing nomenclature, especially as regards trivial names. 

Using this categorization we can also identify some existing nomenclature Hunkeler and Hamielec s inverse-microsuspension refers to two system 1) potassium persulfate/acrylamide-water/organic/low HLB stabilizer [32] which is an inverse-suspension by the proposed scheme, and 2) AIBN/acrylami-de-water/organic/low HLB stabilizer [29] which is an inverse-emulsion. 

The first concerted international effort to develop coherent policies for systematic organic nomenclature was made by the International Commission for the Reform of Chemical Nomenclature at the Geneva Congress in 1892. From the Commission developed what is known today as the International Union of Pure and Applied Chemistry (lUPAC), whose declared function is to systematize and codify existing nomenclature practices insofar as they are determined to be sound. Such efforts have been well documented [15] and have resulted in the publication of comprehensive rules for systematic inorganic and organic nomenclature [16,17]. Paren-... 

It seems that chemical nomenclature is again in the position that existing nomenclature practices are becoming progressively more inadequate and that it may become necessary once again to resolve the developing crisis by introducing a novel nomenclature system, preferably one that is comprehensive. It is currently estimated that a total of about seven million substances have been recorded in the literature and the number is... 

Among those describing problems with existing nomenclature and discussing the need for improvements are Elk [22], Scott [28], Taylor [29], Terent ev el a/[30], Read and Milner [31,32], Balaban [33,34], Dyson [35], Rush [36], Cahn and Denner [37], Lozac h et al [38], GocKlson [39,40], and Bonchev [41]. Efforts to rc dve these problems by modification... 

The last ASTM Standard E94 which classified Industrial Radiography films was published in 1984. Since that time inspection contracts in the U. S. and worldwide have continued to specify Type 1 and Type 2 films which no longer existed. Film manufacturers continued to classify their film using the same nomenclature. 

While the trivial and trade nomenclature in most cases has accidental character, the lUPAC Commission has worked out a series of rules [4] which allow the great majority of structures to be represented uniformly, though there still exists some ambiguity within this nomenclature. Thus, many structures can have more than one name. It is important that the rules of some dialects of the lUPAC systematic nomenclature are transformed into a program code. Thus, programs for generating the names from chemical structures, and vice versa (structures from names) have been created [5] (see Chapter II, Section 2 in the Handbook). 

Gloves. The clove spice is the dried unopened buds of the evergreen tree, Eugenia caryophyllus Thumb (Myrtaceae). This tree is also called Sj gium aromaticum L. Other botanical names are used, but some discrepancies exist as to the proper nomenclature. The tree is indigenous to the Molucca Islands. 

The system of primary interest, then, is that of a condensable vapor moving between a Hquid phase, usually pure, and a vapor phase in which other components are present. Some of the gas-phase components may be noncondensable. A simple example would be water vapor moving through air to condense on a cold surface. Here the condensed phase, characterized by T and P, exists pure. The vapor-phase description requiresjy, the mole fraction, as weU as T and P. The nomenclature used in the description of vapor-inert gas systems is given in Table 1. 

The nomenclature of boron hydride derivatives has been somewhat confusing and many inconsistencies exist in the Hterature. The stmctures of some reported boron hydride clusters are so compHcated that only a stmctural drawing or graph, often accompanied by explanatory text, is used to describe them. Traditional nomenclature systems often can be used to describe compounds unambiguously, but the resulting descriptions may be so long and unwieldy that they are of Htde use. The lUPAC (7) and the Chemical Abstract Service (8) have made recommendations, and nomenclature methods have now been developed that can adequately handle nearly all clusters compounds however, these methods have yet to be widely adopted. Eor the most part, nomenclature used in the original Hterature is retained herein. 

A system based partly on historical names, partly on the substrate, and partly on the type of reaction catalyzed is far from satisfactory. In 1956, the International Union of Biochemistry set up a Commission on Enzymes to consider the classification and nomenclature of enzymes. The Commission presented a report in 1961 whose recommendations for naming and classifying enzymes were subsequently adopted (12). Enzymes are classified on the basis of the reactions they catalyze. Despite its apparent complexities, the system is precise and very descriptive, accommodating existing enzymes and serving as a systematic basis for the naming of new enzymes. AH enzymes are placed in one of the six principal classes. 

Protonation of the anion [SN2] by acetic acid in diethyl ether produces the thermally unstable sulfur diimide S(NH)2. Like all sulfur diimides, the parent compound S(NH)2 can exist as three isomers (Scheme 5.5). Ab initio molecular orbital calculations indicate that the (cis,cis) configuration is somewhat more stable than the (cis,trans) isomer, while the (trans,trans) isomer is expected to possess considerably higher energy. The alternative syn,anti or E,Z nomenclatures may also be used to describe these isomers. The structures of organic derivatives S(NR)2 (R = alkyl, aryl) are discussed in Section 10.4.2. 

There exists in East Indian sandalwood oil an alcohol, of the formula CjHjgO, which has been named santelol, or santenone alcohol. It is closely allied to, and much resembles, the alcohol obtained by the hydration of the hydrocarbon, santene q.v.), and is probably stereo-isomeric with it. There is some difference of opinion as to the proper nomenclature of the two alcohols. According to Charabot, the naturally occurring alcohol, also obtainable by the reduction of santenone, is analogous to borneol, and should therefore be termed, if that analogy is... 

The parent 1,2-diazocine (1) may exist in two bond-isomeric forms. The precise nomenclature, therefore, is either l,2-diazacycloocta-l,3,5,7-tetraene or l,2-diazacycloocta-2,4,6,8-tetraene. It has been shown that the azinc form 1B is normally favored the azo form 1A seems to be relatively unstable.3... 

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