Reaction with chemical

Effects of compounds observable at lower concentrations ai e probably connected with the effect on the initiation/termination stages (transition metals in TMB-0, reaction with photoinitiation, UDMH in the same reaction with chemical initiation), while the compounds influencing only at higher concentrations may affect chain propagation stages. 

Group of plastics composed of resins formulated from the treatment of lignin with heat or by reaction with chemicals. 

Higher paraffinic hydrocarbons than methane are not generally used for producing chemicals by direct reaction with chemical reagents due to their lower reactivities relative to olefins and aromatics. Nevertheless, a few derivatives can be obtained from these hydrocarbons through oxidation, nitration, and chlorination reactions. These are noted in Chapter 6. 

This review is concerned with the formation of cation radicals and anion radicals from sulfoxides and sulfones. First the clear-cut evidence for this formation is summarized (ESR spectroscopy, pulse radiolysis in particular) followed by a discussion of the mechanisms of reactions with chemical oxidants and reductants in which such intermediates are proposed. In this section, the reactions of a-sulfonyl and oc-sulfinyl carbanions in which the electron transfer process has been proposed are also dealt with. The last section describes photochemical reactions involving anion and cation radicals of sulfoxides and sulfones. The electrochemistry of this class of compounds is covered in the chapter written by Simonet1 and is not discussed here some electrochemical data will however be used during the discussion of mechanisms (some reduction potential values are given in Table 1). 

III. REACTIONS WITH CHEMICAL OXIDANTS AND REDUCTANTS A. SET Involving er-Sulfonyl and ar-Sulfinyl Carbanions... 

A number of the techniques that have been employed have the ability to directly monitor free-radical species either in vitro or in vivo [predominantly those involving electron spin resonance (e.s.r.) spectroscopy]. However, since many physiologically relevant free radicals have extremely short half-lives (e.g. 10 s for OH), the majority of the methods utilized detect products arising from their reactions with chemical components present (i.e. indirect methods). These indirect methods for... 

Yoshida, 1980 Handbook of Hazardous Reactions with Chemicals, Yoshida, T., Tokyo, Tokyo Fire Department, 1980 (copy in British Library, Boston Spa)... 

Reaction with Chemically Modified Cytochrome c. Chemically modified (CDNP) cytochrome c derivatives have been prepared by Margoliash and colleagues (22). Lysine residues react as in (17),... 

Table 5.7 Some reactions with chemical hydrides.

Hydroxyl radicals, OH, can undergo several types of reactions with chemical species in aqueous solution. The types of reactions that are likely to occur are hydroxylation, hydrogen abstraction, electron transfer, and radical-radical recombination. Hydroxylation reaction occurs readily with aromatic and unsaturated aliphatic compounds, which result in the formation of hydrox-ylated radicals ... 

DOM is ubiquitous in rivers, lakes, groundwater, and oceans. It therefore plays a dominant role in the biosphere as well as in treatment of fresh water, for industrial use and human consumption. The main aspects in addition to the function as microbial nutrients are (a) the interactions with other water constituents like metals and xenobiotics and (b) the reactions with chemicals that are used for water disinfection (e.g., chlorine). The latter leads to the problem of disinfection by-product (DBP) formation, which is of toxicological relevance. 

Many of the synthetic routes used in the early days of MOCVD involve reactions with chemicals that can subsequently provide impurity atoms in the product. For example, the above Reaction (3) can leave the TEGa with a small amount of TEA1 and Reaction (4) can produce Zn-contaminated TMGa. Note that many metal alkyls are... 

It is no longer sufficient to assume that a chemical is harmless on the grounds that it is nonmutagenic in a simple system. Many chemicals are not mutagenic themselves, but are converted into mutagens in the body, usually in the liver. Reactions with chemicals of external origin lead to a complicated and delicate balance of toxification and detoxification. Intermediate products cure often... 

The observation that the yields of the major products are linear and less than linear shows that they are initial, not secondary, products, in the sense that they are not formed by radiolysis of products or by reaction with chemicals formed by the radiolysis. There is no proof of their direct formation in the initial event of radiation absorption, but they were the major products in the lower dose that made analysis possible. To prove further that the trimers and tetramers are initial products, the radiolysis of 10 M DFBP solution in C6F6 was studied. The yields of trimers and tetramers were the same without DFBP, indicating that they are not formed by the reaction with DFBP. 

Cure To change the properties of a polymeric system into a more stable, usable condition by the use of heat, radiation, or reaction with chemical additives. Note - Cure may be accomplished, for example, by removal of solvent or crosslinking. 

II. Comparison of Electrochemical Reactions with Chemical Oxidations and Reductions with Regard to their Mechanism... 

B, More detailed comparisons of electrochemical reactions with chemical oxidations and reductions... 

II. COMPARISON OF ELECTROCHEMICAL REACTIONS WITH CHEMICAL OXIDATIONS AND REDUCTIONS WITH REGARD TO THEIR MECHANISM... 

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