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A cadmium

Vinyl acetate (ethenyl acetate) is produced in the vapor-phase reaction at 180—200°C of acetylene and acetic acid over a cadmium, 2inc, or mercury acetate catalyst. However, the palladium-cataly2ed reaction of ethylene and acetic acid has displaced most of the commercial acetylene-based units (see Acetylene-DERIVED chemicals Vinyl polymers). Current production is dependent on the use of low cost by-product acetylene from ethylene plants or from low cost hydrocarbon feeds. [Pg.393]

Control of the core is affected by movable control rods which contain neutron absorbers soluble neutron absorbers ia the coolant, called chemical shim fixed burnable neutron absorbers and the intrinsic feature of negative reactivity coefficients. Gross changes ia fission reaction rates, as well as start-up and shutdown of the fission reactions, are effected by the control rods. In a typical PWR, ca 90 control rods are used. These, iaserted from the top of the core, contain strong neutron absorbers such as boron, cadmium, or hafnium, and are made up of a cadmium—iadium—silver alloy, clad ia stainless steel. The movement of the control rods is governed remotely by an operator ia the control room. Safety circuitry automatically iaserts the rods ia the event of an abnormal power or reactivity transient. [Pg.240]

Titanium Dibromide. Titanium dibromide [13873-04-5] a black crystalline soHd, density 4310 kg/m, mp 1025°C, has a cadmium iodide-type stmcture and is readily oxidized to trivalent titanium by water. Spontaneously flammable in air (142), it can be prepared by direct synthesis from the elements, by reaction of the tetrabromide with titanium, or by thermal decomposition of titanium tribromide. This last reaction must be carried out either at or below 400°C, because at higher temperatures the dibromide itself disproportionates. [Pg.131]

Your company receives toluene, a listed toxic chemical, from another facility, reacts the toluene with air to form benzoic acid, and further reacts the benzoic acid with a cadmium catalyst to form terephthallc acid. Cadmium compounds and terephthallc acid are also listed toxic chemicals. Your company processes toluene, and otherwise uses (not processes) the cadmium catalyst (see the definition of "otherwise use" below). Your company manufactures benzoic acid and terephthallc acid. Benzoic acid, however, is not a listed chemical and thus does not trigger reporting requirements. [Pg.26]

Pipette lOmL of a cadmium sulphate solution (1.0gCd2+ L-1) into a 100 mL graduated flask, add 2,5 mL of 0.2 per cent gelatin solution, 50 mL of 2 M potassium chloride solution and dilute to the mark. The resulting solution (A) will contain 0.100gCd2+ L-1 in a base solution (supporting electrolyte) of 1 M potassium chloride with 0.005 per cent gelatin solution as suppressor. [Pg.617]

Anodization is facilitated at alkaline pH by the stability of low oxidation state chalcogen species (e.g., Te ) in this range. Thus, intended corrosion of a cadmium electrode in telluride environment may lead to the formation of CdTe ... [Pg.84]

A cadmium hydroxide complex of composition [TpMe2]Cd0H-H20, obtained as an intractable material from the reactions of both (Et2NCH2CH2NEt2)CdCl2 and (Ph3P)2CdCl2 with K[TpMe2] in acetone, has been reported (89). However, the complex is not well characterized. [Pg.353]

The deposition of cadmium in the form of an amalgam from a cadmium cyanide solution involves the overall reaction... [Pg.261]

The term regulated battery means a rechargeable battery that (a) contains a cadmium or a lead electrode or any combination of cadmium and lead electrodes or (b) contains other electrode... [Pg.1227]

A—Cadmium Cadmium anode Nickel, mercury, and silver Secondary Nickel-cadmium, mercury-cadmium, and silver-cadmium... [Pg.1310]

The photodimerization of simple isolated olefinic bonds is rarely observed because of the absorption of these compounds in the high-energy or vacuum-ultraviolet region. One case reported is that of the photo-dimerization of 2-butene.<2) Irradiation of liquid cw-2-butene with light from a cadmium (A = 229, 227, 214 nm) or zinc (A = 214 nm) lamp was reported to lead to dimers (1) and (2) ... [Pg.219]

Bronson RT, Michaelis DJ, Lamb RD et al (2005) Efficient immobilization of a cadmium chromosensor in a thin film feneration of a cadmium sensor prototype. Org Lett 7 1105-1108... [Pg.261]

Bingham F.T., Page A.L., Mahler R.J., Ganji T.J. Growth and cadmium accumulation of plants grown on a soil treated with a cadmium-enriched sewage sludge. J Environ Qual 1975 4 207-211. [Pg.331]

Hirsh D., Banin A. Cadmium speciation in soil solutions. J Environ Qual 1990 19 366-372. [Pg.339]

Moreno J.L., Hernandez T., Garcia C. Effect of a cadmium-contaminated sewage sludge compost on dynamics of organic matter and microbial activity in an arid soil. Bio Ferti Soils 1999 28 230-237. [Pg.346]

Unusual arene-cadmium 7r-complexes have been recently prepared and structurally characterized. For example, the /w /zz-bcn/i porphyrin complex 194, which can be obtained by reaction of the free base with CdCl2, possesses a cadmium atom that is bound to the Mfez-phcnylcnc unit of the ligand in an apparent /-fashion (Figure 32). The resulting Cd-C distance of 2.71 A is shorter than the sum of the van der Waals radii.252 Despite this relatively short contact, DFT calculations and AIM analysis point to the weakness of the interaction. Comparable weak arene-cadmium 7r-interactions are also observed in the /wra-benziporphyrin cadmium chloride complex 195.253... [Pg.465]

Nitrile rubber can be cured by sulphur, sulphur donor systems and peroxides. However, the solubility of sulphur in nitrile rubber is much lower than in NR, and a magnesium carbonate coated grade (sulphur MC) is normally used this is added as early in the mixing cycle as possible. Less sulphur and more accelerator than is commonly used for curing natural rubber is required. A cadmium oxide/magnesium oxide cure system gives improved heat resistance, but the use of cadmium, a heavy metal, will increasingly be restricted. [Pg.90]

In terms of their chemical behavior, dialkylzinc compounds generally react to transfer alkyl groups to other metals. Dialkyls of cadmium are usually prepared by the reaction of a Grignard reagent with a cadmium halide. [Pg.411]

A modified SILAR system has been used to grow CdSe in CdS/CdSe core shell semiconductor nanocrystals.12 A cadmium precursor solution, with CdO dissolved with oleic acid in octadecane, was injected onto the substrate, and the Se solution (Se powder dissolved with tributylphosphine in octadecane) was similarly injected. The temperature of the reaction solution was 185 °C. A CdS outer layer in the CdS/CdSe/CdS colloidal quantum wells was deposited by alternating injections of cadmium and sulfur both in octadecane solutions at 230-240 °C. These structures showed high PL quantum yields (20-40%), relatively narrow emission bands, and tunable emission colors from about 520 to 650 nm depending on the number of CdSe monolayers. [Pg.258]


See other pages where A cadmium is mentioned: [Pg.435]    [Pg.132]    [Pg.334]    [Pg.426]    [Pg.323]    [Pg.232]    [Pg.95]    [Pg.446]    [Pg.474]    [Pg.22]    [Pg.219]    [Pg.221]    [Pg.47]    [Pg.135]    [Pg.101]    [Pg.267]    [Pg.134]    [Pg.164]    [Pg.349]    [Pg.218]    [Pg.329]    [Pg.417]    [Pg.423]    [Pg.1303]    [Pg.1311]    [Pg.1320]    [Pg.234]    [Pg.234]    [Pg.285]    [Pg.254]    [Pg.334]    [Pg.374]   
See also in sourсe #XX -- [ Pg.432 , Pg.442 ]




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