INDEX purpose

Botanical names are printed in italics. Prefixes snch as nor-, iso-, proto-, apo-, are printed in italics and disregarded for indexing purposes.- Where more than one page number is given, a chief descriptive reference is indicated hy the use of heavier type.)... 

Substituents replacing the hydrogen atom of an alcoholic hydroxy group of a saccharide or saccharide derivative are denoted as O-substituents. The 0- locant is not repeated for multiple replacements by the same atom or group. Number locants are used as necessary to specify the positions of substituents they are not required for compounds fully substituted by identical groups. Alternative periphrase names for esters, ethers, etc. may be useful for indexing purposes. For cyclic acetals see 2-Carb-28. 

The principal advances in the systematization of organic nomenclature have come from the International Union of Pure and Applied Chemistry (IUPAC) Commission on the Nomenclature of Organic Chemistry, and from the Chemical Abstracts Service. The IUPAC Definitive Rules for Hydrocarbons and Heterocyclic Systems (1957)4 and for Characteristic Groups (1965)5 have been widely accepted by the chemical community, and, in their latest revised form,6 constitute the standard reference work. These rules are closely related to those developed in parallel by Chemical Abstracts for indexing purposes, and it is fortunate that, as a result of close cooperation between the two bodies, there are few areas of disagreement. 

Although Hantzsch-Widman system works satisfactorily (if you can remember the rules) for monocyclic compounds, it is cumbersome for polycyclic compounds. In the case of oxiranes it is simplest for conversational purposes to name them as oxides of the cycloalkenes or epoxy derivatives of the corresponding cycloalkanes. The oxabicycloalkane names seem preferable for indexing purposes, particularly because the word oxide is used in many other connections. 

For indexing purposes, American spelling has been used, e.g. anemia, estrogen, rather than anaemia, oestrogen. 

PEEP index Potential Ecotoxic Effects Probe index Purpose... 

Department of Chemistry, University of Massachusetts, Amherst, MA 01003. Cyclodiphosph(lII)azanes is commonly used nomenclature, but the more systematic ring name l,3-di>ter(-butyl-2,4-dichloro-l,3,2,4-diazadiphosphetidine is used for indexing purposes. 

If a title is self-explanatory and adequate for indexing purposes, there is no abstract or annotation in Chemical Abstracts. Such cases are rare for analytical methods. In general one wants to know what was done, how, and the results obtainable for given substances or conditions. The information desired may be much the same as that suggested for a satisfactory summary. For example, the method may be for small amounts of silica. The reader wants to know if the procedure is colorimetric. If so, was the colored species developed a heteropoly acid If so, what was the color-forming reagent Too often these and similar questions are not answered. 

Swedish linkers are quoted on yield basis, but for pricing and inflation indexation purposes the bonds adopt a similar methodology to Canada, France, and the United States. 

All the faces of a crystal can be described and numbered in terms of their axial intercepts. The axes referred to here are the crystallographic axes (usually three) which are chosen to fit the symmetry one or more of these axes may be axes of symmetry or parallel to them, but three convenient crystal edges can be used if desired. It is best if the three axes are mutually perpendicular, but this cannot always be arranged. On the other hand, crystals of the hexagonal system are often allotted four axes for indexing purposes. 

For indexing purposes American spelling has, with a few exceptions, been used, e.g. anemia and estrogen rather than anaemia and oestrogen . 

Having reduced the problem of polymer nomenclature to one of source nomenclature, it is now necessary to choose one of the established systems of naming organic compounds. Chemical Abstracts has long set the standard for systematic chemical nomenclature for indexing purposes, which at the same time conforms to accepted... 

Since much of the available literature, particularly commercial data sheets, use the term N-vinylpyrrolidone for the monomer of Structure I, this name will also be used throughout this chapter. The term l-vinyl-2-pyrrolidone offers a more precise description of the molecule. Older volumes of Chemical Abstracts use the term l-vinyl-2-pyrrolidinone the current indexes use l-ethenyl-2-pyrrolidinone (/.e., for indexing purposes, 2-pyrrolidinone, l-ethenyP ). 

Descriptor describing keyword, which is used for indexing purposes and is part of the keyword list or of the thesaurus. 

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