Effect of metal compounds

Ramel C. 1973. The effect of metal compounds on chromosome segregation. Mut Res 21 45-46. 

Kurokawa Y, Matsushima M, Imazaawa T, et al. 1985. Promoting effect of metal compounds on rat renal tumorigenesis. J Am Coll Toxicol 4 321-331. 

The effect of metal compounds on HC1 evolution has been noted by many authors. Thus, Hartmann (12, 13) pointed out that lead and di-butyltin compounds did not affect dehydrochlorination rate, but ferric salts and zinc chloride accelerated it. Rafikov and co-workers (22) reported that lead and calcium soaps promoted crosslinking. These investigators do not seem to have considered the hypothesis that dehydrochlorination is accelerated as a consequence of crosslinking. 

Berrow, M. L. and J. C. Burridge. 1991. Uptake, distribution, and effects of metal compounds on plants. In E. Merian, Ed. Metals and Their Compounds in the Environment Occurrence, Analysis, and Biological Relevance. VCH Publishers, New York, pp. 399-410. 

The available data concerning the effect of metal compounds on the pyrolysis and combustion of polymeric materials show that there is a great potential in the control of these materials, This field is still in its embryonic stage. Much is yet unclear. In many cases the analysis is rendered difficult because of the dual function of metal compounds (especially of the d- and f-types) in redox reactions. Their ability not only to inhibit but also to promote polymer decomposition manifests itself most clearly in concentration effects The specific effects of certain metal compounds on the ignition and combustion rate of polymers indicate that heterogeneous oxidation... 

The retarding effect of metal compounds on the flaming combustion of polymers must be primarily attributed to the decrease of the yield of flammable volatile pyrolysis products. There are two alternative paths 1) catalysis of the formation of non-combustible products (COj, HjO) 2) inhibition of polymer decomposition at the high temperatures developed during steady-state combustion (high-temperature stabilization)... 

The discovery of the catalytic effect of metal compounds on the reaction of isocyanates with alcohols came relatively recently (37) and led eventually to finding of the most potent catalysts of this kind in certain organometallic derivatives of tin (SS). 

Byczkowski JZ, Sorenson J JR. 1984. Effects of metal compounds on mitochondrial function A review. Sci Total Environ 37 133-162. 

Kim, K. J., Doi, Y, and Abe, H. (2008). Effect of metal compounds on thermal degradation behavior of aliphatic poly(hydro5qralkanoic acid)s, Polym. Degrad. Stab., 93,776-785. 

Workers in the metals treatment industry are exposed to fumes, dusts, and mists containing metals and metal compounds, as well as to various chemicals from sources such as grinding wheels and lubricants. Exposure can be by inhalation, ingestion, or skin contact. Historically, metal toxicology was concerned with overt effects such as abdominal coHc from lead toxicity. Because of the occupational health and safety standards of the 1990s such effects are rare. Subtie, chronic, or long-term effects of metals treatment exposure are under study. An index to safety precautions for various metal treatment processes is available (6). As additional information is gained, standards are adjusted. 

As discussed in Chapter 2, nickel, vanadium, and sodium are the metal compounds usually present in the FCC feedstock. These metals deposit on the catalyst, thus poisoning the catalyst active sites. Some of the options available to refiners for reducing the effect of metals on catalyst activity are as follows ... 

Pentasodium pentetate, tetrasodium etidronate, and tetra-sodium EDTA are added as water softeners and to protect the dyes and perfumes from the effects of metal ions in the mixtures. These compounds lock up calcium and magnesium in the water, preventing them from reacting with the soap to form insoluble soap scum. 

Effect of metals, organometallic compounds and strong bases... 

Ceria-based OSC compounds may have an impact on oxidation reactions especially when the catalysts are working around the stoichiometry (as this is the case under TW conditions). One of the first systematic studies was reported by Yu Yao [53,54], Most results were obtained in 02 excess (0.5% CO + O.5% 02 or 0.1% HC+ 1% 02). Several series of Pt, Pd and Rh/Al203 of various dispersion, as well as metal foils, were investigated in CO, alkane and alkene oxidation. The effect of metal dispersion in CO and the propane oxidation are shown in Figure 8.5. 

In a review of the course and mechanism of the catalytic decomposition of ammonium perchlorate, the considerable effects of metal oxides in reducing the explosion temperature of the salt are described [1], Solymosi s previous work had shown reductions from 440° to about 270° by dichromium trioxide, to 260° by 10 mol% of cadmium oxide and to 200°C by 0.2% of zinc oxide. The effect of various concentrations of copper chromite , copper oxide, iron oxide and potassium permanganate on the catalysed combustion of the propellant salt was studied [2], Similar studies on the effects of compounds of 11 metals and potassium dichromate in particular, have been reported [3], Presence of calcium carbonate or calcium oxide has a stabilising effect on the salt, either alone or in admixture with polystyrene [4],... 

The effect of metal basicity on the mode of reactivity of the metal-carbon bond in carbene complexes toward electrophilic and nucleophilic reagents was emphasized in Section II above. Reactivity studies of alkylidene ligands in d8 and d6 Ru, Os, and Ir complexes reinforce the notion that electrophilic additions to electron-rich compounds and nucleophilic additions to electron-deficient compounds are the expected patterns. Notable exceptions include addition of CO and CNR to the osmium methylene complex 47. These latter reactions can be interpreted in terms of non-innocent participation of the nitrosyl ligand. 

O Nickel and copper are both very important to the Ontario economy. Before they can be refined by electrolysis, they must be extracted from their ores. Both metals can be extracted from a sulfide ore, NiS or CU2S. The sulfide is roasted to form an oxide, and then the oxide is reduced to the metal. Research the extraction processes for both nickel and copper, and write balanced equations for the redox reactions involved. One product of each extraction process is sulfur dioxide. Research the environmental effects of this compound. Describe any steps taken to decrease these effects. 

The effects of various compounds and inhibitors on the enzyme activity were tested. The activity was measured in the presence of 1 -10 mM of various metal ions and compounds. The enzyme activity was inhibited by sulfhydryl reagents (concentration 1 mM) such as PbCl2 (relative activity, 18%), SnCl2 (17%),HgCl2... 

Reish D. 1993. Effects of metals and organic compounds on survival and bioaccumulation in two species of marine gammaridean amphipod, together with a summary of toxicological research on the group. 

Oxidative reactions of organic compounds with molecular oxygen take place with high efficiency and selectivity in the presence of Werner-type metal complexes used as catalysts. The catalytic effects of metal complexes have received attention also as models for metalloenzymes, which are catalysts that possess special high efficiency and high selectivity for oxidative reactions in vivo. 

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