Dithiocarbamates diethyl

Reconstitution of T-ceU deficiencies with thymic hormones has not been successhil even though the various hormone preparations induce prothymocyte differentiation and functions of mature T-ceUs. They do not regulate the maturation of thymocytes in the thymus. In contrast, IL-2, endotoxin, thymic epithehal cell products, but not interleukin 1, were found to promote functional maturation of immature thymocytes. Two classes of dmgs show thymomimetic actions (Table 2). Levamisole [14769-73-4], sodium salt of diethyl dithiocarbamate (imuthiol) and certain... 

Rubber. The mbber industry consumes finely ground metallic selenium and Selenac (selenium diethyl dithiocarbamate, R. T. Vanderbilt). Both are used with natural mbber and styrene—butadiene mbber (SBR) to increase the rate of vulcanization and improve the aging and mechanical properties of sulfudess and low sulfur stocks. Selenac is also used as an accelerator in butyl mbber and as an activator for other types of accelerators, eg, thiazoles (see Rubber chemicals). Selenium compounds are useflil as antioxidants (qv), uv stabilizers, (qv), bonding agents, carbon black activators, and polymerization additives. Selenac improves the adhesion of polyester fibers to mbber. 

Certain, Y, Y-dialkyl dithioearbamates [e,g. benzyl A)/V-diethyl dithiocarbamate (14)] and xanthates have been used as photoinitiators. Photodissociation of the C-S bond of these compounds yields a reactive alkyl radical (to initiate polymerization) and a less reactive sulfur-centered radical (to undergo primary-radical termination) as shown in Scheme 9.9.30 41 4 ... 

Laboratory method using porous polymer adsorbent tubes, thermal desorption and gas chromatt raphy MDHS 32 Dioctyl phthalates in air Laboratory method using Tenax adsorbent tubes, solvent desorption and gas chromatography MDHS 33 Adsorbent tu standards Preparation by the syringe loading technique MDHS 34 Arsine in air Colorimetric field method using silver diethyl-dithiocarbamate in the presence of excess silver nitrate... 

Takeuchi, K., Nishiwaki, H., Niida, H., Ueshima, K. and Okabe, S. (1991b). Duodenal ulcers induced by diethyl-dithiocarbamate, a superoxide dismutase inhibitor, in the rat role of antioxidative system in the pathogenesis. Jpn. J. Pharmacol. 57, 299-310. 

Cobalt(III) complexes of formula cis- and trans-[Co(dtc)L4]2+ and [Co(dtc)2L2]+ where dtc = dimethyl-, diethyl- or piperidino-dithiocarbamate were prepared with phosphites P(OMe)3, P(OEt)3 and 4-ethyl-2,6,7-trioxa-l-phophabicyclo[2.2.2]octane as ligands L.1048 Whereas Co—P bonding is found, as defined in the crystal structures of each of the two forms of complexes isolated, a linkage isomer in which the phosphite is O bound was detected for the bis(dithio-carbamate) compounds. 

A class of very fast accelerators for rubber, particularly useful in latex work. The principal member of the class is zinc diethyl dithiocarbamate. 

Natural rubber latices in which the customary 0.7% ammonia content has been reduced to 0.2% in conjunction with the addition of a secondary preservative, either sodium pentachlorophenate, zinc diethyl dithiocarbamate or boric acid such latices have the advantage that the deammoniation process before manufacture is unnecessary. 

Mullins [37] has described a procedure for determining the concentrations of dissolved chromium species in seawater. Chromium (III) and chromium (VI) separated by co-precipitation with hydrated iron (III) oxide and total chromium are determined separately by conversion to chromium (VI), extraction with ammonium pyrrolidine diethyl dithiocarbamate into methyl isobutyl ketone, and determination by AAS. The detection limit is 40 ng/1 chromium. The dissolved chromium not amenable to separation and direct extraction is calculated by difference. In waters investigated, total concentrations were relatively high (1-5 xg/l), with chromium (VI) the predominant species in all areas sampled with one exception, where organically bound chromium was the major species. 

Hg, Au, Cu Lead diethyl dithiocarbamate Neutron activation analysis [820]... 

Metal dialkyl dithiocarbamates inhibit the oxidation of hydrocarbons and polymers [25,28,30,76 79]. Like metal dithiophosphates, they are reactive toward hydroperoxides. At room temperature, the reactions of metal dialkyl dithiocarbamates with hydroperoxides occur with an induction period, during which the reaction products are formed that catalyze the breakdown of hydroperoxide [78]. At higher temperatures, the reaction is bimolecular and occurs with the rate v = k[ROOH][inhibitor]. The reaction of hydroperoxide with dialkyl dithiocarbamate is accompanied by the formation of radicals [30,76,78]. The bulk yield of radicals in the reaction of nickel diethyl dithiocarbamate with cumyl hydroperoxide is 0.2 at... 

Living radical polymerizations have received considerable attention because they provide a convenient alternative for synthesizing block copolymers, polymers of narrow polydispersity and complex polymer structures (1-5). Because of their ability to initiate living free radical polymerizations, iniferters have been examined extensively after Otsu et al. (6) introduced them in 1982. In particular, dithiocarbamate derivatives have been studied more closely by several researchers. Lambrinos et al (7) have examined the molecular weight evolution during the polymerization of n-butyl acrylate using p-x ylylene bis(A,A-diethyl... 

Pb Food Extract Pb w/diethyl-ammonium diethyl-dithiocarbamate into xylene in presence of ascorbic acid 273)... 

Block, M. and Part, P. (1986). Increased availability of cadmium to perfused rainbow trout (Salmo gairdneri, Rich) gills in the presence of the complexing agents diethyl dithiocarbamate, ethyl xanthate and isopropyl xanthate, Aquat. Toxicol., 8, 295-302. 

The limitations of the Gutzert method for determining arsenic are well known. The spectrophotometric molybdenum blue or silver diethyl/ dithiocarbamate procedures tend to suffer from poor precision and accuracy as shown in collaborative studies [115, 116]. 

In order to characterize the adsorption species on mineral surface, DDTC is oxidized into the dimmer by adding definite H2O2 into the DDTC solution, which then is extracted by cyclohexane to determine its UV spectrum. As seen from the UV spectrum in Fig. 4.33, there are three UV absorbance peaks at 230 nm, 261 nm, 280 nm respectively. The maximum absorbance peak is at 230 nm, the next peak is at 260 nm, and the weak peak is at 280 nm. The peak at 230 nm can serve as a characteristic absorbance peak, and the peak at 260nm results from absorbance overlapping of diethyl dithiocarbamate and its dimmer. 

The UV spectra of the cyclohexane solution extracted from jamesonite acted by DDTC solution, shown in Fig. 4.34, indicates that the adsorption of diethyl dithiocarbamate on the surface of jamesonite is almost the same at pH = 4 and 7, but decreases with the increasing of pH in the base solution. Because the UV spectra in Fig. 4.33 and Fig. 4.34 are similar with peaks at 230 mn and 260 nm, it indicates that the hydrophobic species on jamesonite should be the mixture of diethyl dithiocarbamate and its dimmer. 

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