Identification of chemical substances

ChemIDplus. Published by the U.S. National Library of Medicine, ChemIDplus [62] is a web-based search system, http //chem.sis.nlm.nih.gov/ chemidplus/, that provides free access to structure and nomenclature authority files used for the identification of chemical substances cited in National Library of Medicine (NLM) databases. ChemIDplus also provides structure searching and direct links to biomedical resources at NLM and on the Internet. The database contains over 349,000 chemical records, over 56,000 of which include chemical structures, and is searchable by name, synonym, CAS registry number, molecular formula, classification code, locator code, and structure. 

The identification of chemical substances by examination of their spectra (singular, spectrum). Both infrared and ultraviolet spectroscopy are used in the study of rubber problems such as identifying the type of polymer or the nature of a contaminant. 

The file A(C) Identifiers and Definitions (see Table 1) is a new file, which at present only a few users outside the JRC can access. The file will be made available to users in general during the summer of 1987. The file will contain data related to the identification of chemical substances for legislative purposes. The first data to be accessible in the file will come from the fists of chemicals maintained by the Commission, but, later, data originating fi om national files and from other international organisations will also be entered. The current file contains only data related to the EINECS Inventory. 

Professor Martel s book addresses specifically some of the more technical eispects of the risk assessment process, mainly in the areas of hazard identification, and of the consequence/effect analysis elements, of the overall analysis whilst where appropriate setting these aspects in the wider context. The book brings together a substantial corpus of information, drawn from a number of sources, about the toxic, flammable and explosive properties and effect (ie harm) characteristics of a wide range of chemical substances likely to be found in industry eind in the laboratory, and also addresses a spectrum of dangerous reactions of, or between, such substances which may be encountered. This approach follows the classical methodology and procedures of hazard identification, analysing material properties eind... 

This chapter will give an overview of recent international trends and initiatives regarding chemicals in leather and articles containing leather. That includes the identification of chemicals in the produced leather that are common on restricted substance lists and present ongoing recent initiatives to control the impact from these chemicals including both legislative measures and initiatives from customers such as international brands or purchasing sectors and different eco-labels. 

Furthermore, the EU regularly produces and regularly updates the list of substances of high concern, i.e. the SVHC list. The identification of a substance as a SVHC and its inclusion in the candidate list is the first step of the authorization procedure. The European Chemical Agency in Helsinki identifies from the candidate list priority substances to be included in Annex XIV of REACH (the authorisation list). The substances on the candidate list will most probably be liable to stricter regulation in the future (authorisation/banning) which will stimulate the substitution of these chemicals. Currently in June 2012, there are 84 substances included in the candidate list. Examples of chemicals on the candidate list which may be relevant for the leather industry are phenolphthalein, boric acid, cobalt dichloride, dichromate (although not used by leather industry), phthalates (DEHP, DBP and BBP), acrylamide and short-chain chlorinated paraffins. 

Carr, W. and Chaney, T. B. (1976). Chemical stimulation of feeding behavior in the pinfish, Lagodon rhomboides characterization and identification of stimulatory substances extracted from shrimp. Comparative Biochemistry and Physiology 54A, 437-441. 

Saltpeter plus charcoal yields an alkali salt which hath a taste like that of the Salt of Tartar [potassium carbonate], and they differ but little in virtue.He does not say they are identical, though they would both be impure potassium carbonate. There simply did not exist at this time a clear conception of the idea of chemical substance, defined by material composition. The chief means of identifying an artificially prepared body was by its method of preparation. The inevitable presence of impurities made precise identification by explicit properties uncertain in any case, and here Lemery exhibits proper caution in indicating only the similarity rather than the identity of salt of tartar and the product of charcoal in molten saltpeter. 

TESTING (Chemical). Identification of a substance by means of reagents, chromatography, spectroscopy, melting and boiling point determination, etc. 

ECHA (2008b) Press Release /PR/08/34, ECHA member state committee agrees on the identification of 14 substances of very high concern, European Chemicals Agency, Helsinki, Finland. 

The selective absorption of ultraviolet, visible and infrared radiation by molecules is explained in a descriptive manner that stresses how the noncontinuous energy requirements of chemical substances can only be satisfied by photons that have energy values equivalent to that of the differences in energy levels of the molecule in question. The meaning and quantitative significance of Beer s Law is briefly discussed. The components of a simple spectrophotometer are illustrated, accompanied by a demonstration of the operation of a spectrophotometer in the laboratory. Actual applications of the techniques of spectrophotometry are described during the presentation of relevent topics, for example, in drug identification. 

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