Substances categories

HBCD is classified in the Type I Monitoring Chemical Substances category. The criteria in this category include the following ... 

Table 5.1 Data requirements for different tonnage bands and substance categories in the previous legislation and within REACH Previous legislation REACH... 

CMR substances are divided into three categories according to the level of evidence of the substance category 1 (considerable evidence), category 2 (some evidence) and 3 (limited evidence). 

The majority of the industrially applied biotechnical processes for the generation of flavour preparations relies on reactions with isolated enzymes and enzyme complexes. The basic principle of enzymatic reactions is mostly hydrolytic decomposition or transformation of the most important biological substance categories like proteins, carbohydrates, lipids and acids. 

A result of the risk assessments was that DEHP, DBP and BBP are toxic for reproduction. Accordingly, they were classified as CMR (carcinogen, mutagen, reprotoxic) substances, category 2 which is reflected in the classification and labelling with R-phrases 60-62 (Tables 12, 13). 

For a listing of toxic substance categories as defined within the Chemicals on Reporting Rules database, access https //www.unh.edu/ehs/pdf/TSCA-CORR-By-CAS.pdf. 

Table 1.8.1 summarizes the procedure for important substance categories. 

For substances like genotoxic carcinogens or mut enic substances Category I or n (according to the EU classification for hazardous substances), a NOAEL or LOAEL cannot be establish. To minimise exposure to tfa substances, TRK values were established, reflecting the airborne concentration of a hazardous substances which can be achieve with the available techniques . ... 

The carcinogenic and mutagenic substances, category 1 or 2, listed in the appendix of Directive 76/769/EEC[4-5] and preparations containing these substances above 0.1% must be marked legibly and indelibly as follows ... 

The first definition of the chemical element, in the modem sense, is due to R. Boyle (1627-1629) in his book Skeptical Chemist, he defined the chemical element as a substance which cannot be decomposed into other substances. So, the elements (simple bodies) are not composed of other substances, but they themselves are the products in which are decomposed, ultimately, all other substances. Boyle did not shown specifically what these items were about, for example, he could not decide if metals or their oxides had a character of an element. On the other hand, the negation, which stay on the basis of his statement, make it uncertain as a practical definition, because even not known the decomposition methods for a substance at a given time (historical epoch), this not necessarily means that such a decomposition is not possible in an arguable future. In any case, the use of the term element, in the sense of elemental substance, i. e., simple substance, was maintained until now, with the note that only its significance was made clear as time passed by. An important step was the transition from the meaning of the element notion as principle, encompassing a collection of properties, to some specific to substance type. Noteworthy, Lavoisier, in his famous Elementary Treatise of Chemistry (1789) included in the simple substances category approximate 40 substances, of which 25 were really elements (Horovitz et al., 2000). 

The United States Department of Labor—Bureaus of Labor Statistics April 10, 2002 report USDL 02-196 is designated as Lost-Worktime Injuries Characteristics and Resulting Time Away from Work, 2000. Table 4 is titled Number of nonfatal occupational injuries and illnesses involving days away from work by selected injury and illness characteristics and industry division, 2000. One of the categories in the listing of Event(s) or exposure(s) leading to injury or illness is Exposure to harmful substances. Of the 1,477,800 injuries and illnesses covered in Table 4, 69,100 are in the Exposure to harmful substances category. That s 4.7% of the total. 

Applications of Raman to polymer/additive deformulation are still rather few, especially if compared to IR methods (cfr. Chp. 1.2.1). Hummel [108] has attributed the general lack of applications of RS in the field of plastics additives to poor Raman scattering of certain substance categories, unsatisfactory reproducibility of the spectra and scarcity of specific Raman libraries [385,386]. Polymer/additive analysis by means of Raman spectroscopy is mainly restricted to fillers, pigments and dyes the major usefulness comes from NIR FT-Raman, which greatly overcomes the fluorescence problem. The ion-pair dissociation effect of the 2-keto-4-(2,5,8,11-tetraoxadodecyl)-l,3-dioxolane modified carbonate (MC3) plasticiser in poly(ethylene oxide) (PEO) was studied by means of Raman, FTIR and EX-AFS [387]. Another study established the feasibility of using Raman spectroscopy to quantify levels of melamine and melamine cyanurate in nylons [388]. 

Substances in this category include Krypton, sodium chloride, and diamond, as examples, and it is not surprising that differences in detail as to frictional behavior do occur. The softer solids tend to obey Amontons law with /i values in the normal range of 0.5-1.0, provided they are not too near their melting points. Ionic crystals, such as sodium chloride, tend to show irreversible surface damage, in the form of cracks, owing to their brittleness, but still tend to obey Amontons law. This suggests that the area of contact is mainly determined by plastic flow rather than by elastic deformation. 

In the Lewis and Gibson statement of the third law, the notion of a perfect crystalline substance , while understandable, strays far from the macroscopic logic of classical thennodynamics and some scientists have been reluctant to place this statement in the same category as the first and second laws of thennodynamics. Fowler and Guggenheim (1939), noting drat the first and second laws both state universal limitations on processes that are experunentally possible, have pointed out that the principle of the unattainability of absolute zero, first enunciated by Nemst (1912) expresses a similar universal limitation ... 

The word portal is often used for web sites that function as an entiy to a repo-sitoiy of information on almost any topic on the Internet. The following portal categories for chemical issues arc distinguished general chemistry sites substance information sites analytical chemistiy sites enviromnental chemistry sites toxicology and occupational health sites as well as patent seiwices [47],... 

Enzyme action is frequently accelerated or retarded by the presence of other substances both organic and inorganic. Such substances have been divided into three categories (a) co-enzymes, without which certain enzymes are unable to function (i) activators, and (c) inhibitors. 

Theoretical Models of the Response Surface Mathematical models for response surfaces are divided into two categories those based on theory and those that are empirical. Theoretical models are derived from known chemical and physical relationships between the response and the factors. In spectrophotometry, for example, Beer s law is a theoretical model relating a substance s absorbance. A, to its concentration, Ca... 

To examine a sample by inductively coupled plasma mass spectrometry (ICP/MS) or inductively coupled plasma atomic-emission spectroscopy (ICP/AES) the sample must be transported into the flame of a plasma torch. Once in the flame, sample molecules are literally ripped apart to form ions of their constituent elements. These fragmentation and ionization processes are described in Chapters 6 and 14. To introduce samples into the center of the (plasma) flame, they must be transported there as gases, as finely dispersed droplets of a solution, or as fine particulate matter. The various methods of sample introduction are described here in three parts — A, B, and C Chapters 15, 16, and 17 — to cover gases, solutions (liquids), and solids. Some types of sample inlets are multipurpose and can be used with gases and liquids or with liquids and solids, but others have been designed specifically for only one kind of analysis. However, the principles governing the operation of inlet systems fall into a small number of categories. This chapter discusses specifically substances that are normally liquids at ambient temperatures. This sort of inlet is the commonest in analytical work. 

Most bulk food ingredients, eg, flour, fats and oils, and nutritive sweeteners (qv) such as sugar (qv), are excluded from the food additive category. In a few cases, substances that are used in relatively large quantities, eg, dietary fiber (qv) and bulking agents, are included herein because these have been the focus of market and technology developments. 

Photochromic Organic Dyes. Intensive investigations into this category of substances have led to numerous patent appHcations. Copper—phthalocyanine pigments, organic dyes based on cyanine (Ricoh, Pioneer), naphthochinone (Nippon Denki), and ben2othiopyrane (Sony) (123) have been described. They did not lead, however, to any commercial use. Surveys on the possibiUties of optical data storage with photochromic dyes can be found (124,125). 

Liquid crystals may be divided into two broad categories, thermotropic and lyotropic, according to the principal means of breaking down the complete order of the soHd state. Thermotropic Hquid crystals result from the melting of mesogenic soHds due to an increase in temperature. Both pure substances and mixtures form thermotropic Hquid crystals. In order for a mixture to be a thermotropic Hquid crystal, the different components must be completely miscible. Table 1 contains a few examples of the many Hquid crystal forming compounds (2). Much more is known about calamitic (rod-Hke) Hquid crystals then discotic (disk-like) Hquid crystals, since the latter were discovered only recendy. Therefore, most of this section deals exclusively with calamities, with brief coverage of discotics at the end. 

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