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Metal ratios

If all these holes were filled, the hydrogen-metal ratio would be a definite and fixed number in practice, this rarely happens, and... [Pg.112]

Bismuth trioxide forms numerous, complex, mixed oxides of varying composition when fused with CaO, SrO, BaO, and PbO. If high purity bismuth, lead, and copper oxides and strontium and calcium carbonates are mixed together with metal ratios Bi Pb Sn Ca Cu = 1.9 0.4 2 2 3 or 1.95 0.6 2 2 3 and calcined at 800—835°C, the resulting materials have the nominal composition Bi PbQ4Sr2Ca2Cu20 and Bi 25PbQgSr2Ca2Cu20 and become superconducting at about 110 K (25). [Pg.130]

As a result of nuclear fission the oxygen/metal ratio increases in the fuel across tire wide range of non-stoichiometry of UO2+J . The oxygen potential of... [Pg.249]

Good rhodium retention results were obtained after several recycles. However, optimized ligand/metal ratios and leaching and decomposition rates, which can result in the formation of inactive catalyst, are not known for these ligands and require testing in continuous mode. As a reference, in the Ruhrchemie-Rhone-Poulenc process, the losses of rhodium are <10 g Rh per kg n-butyraldehyde. [Pg.268]

In the latter function, the reagent behaves as a surfactant and forms a cationic micelle at a concentration above the critical micelle concentration (1 x 10 4M for CTMB). The complexation reactions occurring on the surface of the micelles differ from those in simple aqueous solution and result in the formation of a complex of higher ligand to metal ratio than in the simple aqueous system this effect is usually accompanied by a substantial increase in molar absorptivity of the metal complex. [Pg.172]

Kd = distribution coefficient (as defined above) s/m = salt to metal ratio by weight F = fraction of equilibrium attained B = effects of side reactions... [Pg.386]

Palladium NHC systems for the hydrodehalogenation of aryl chlorides and bromides and polyhalogenated aromatic substrates originate from about the same time as the first reports on Ni chemistry, and show many similarities. Initial efforts showed that the combination of PdCdba) (2 mol%), one equivalent of imidazolium chloride and KOMe produced an effective system for the reduction of 4-chlorotolu-ene, especially upon use of SIMes HCl 2 (96% yield of toluene after 1 h at 100°C) [7]. Interestingly, higher ligand to metal ratios severely inhibited the catalysis with only 7% yield of toluene achieved in the same time in the presence of two equivalents of SIMes HCl 2. Variation of the metal source (Pd(OAc)2, Pd(CjHjCN)jClj), alkoxide (NaOMe, KO Bu, NaOH/ ec-BuOH) or imidazolium salt (IMes HCl 1, IPr HCl 3, lAd HCl, ICy HCl) all failed to give a more active catalyst. [Pg.211]

If the thiomalate ligand is not present in excess, it is completely displaced. When gold binds, the M ions are displaced in the gold metal ratio of 3 2, which suggests bidentate coordination. EXAFS data shows AuS2 coordination with Au—S bond lengths of 229 pm [20, 103]. In the presence of both cadmium and zinc, zinc is preferentially displaced which is possibly a consequence of thermodynamics as Zn7MT and CdyMT react at comparable rates. [Pg.299]

Epithermal vein-type deposits can be divided into four types based on total metal produced and metal ratio base-metal type, precious-metal (Au, Ag) type, Sb-type and Hg-... [Pg.83]

As noted already, epithermal vein-type deposits are classified primarily on the basis of their major ore-metals (Cu, Pb, Zn, Mn, Au and Ag) into the gold-silver-type and the base-metal-type. Major and accessory ore-metals from major vein-type deposits in Japan were examined in order to assess the possible differences in the metal ratios in these two types of deposits (Shikazono and Shimizu, 1992). Characteristic major ore-metals are Au, Ag, Te, Se and Cu for the Au-Ag deposits, and Pb, Zn, Mn, Cu and Ag for the base-metal deposits (Shikazono, 1986). Accessary metals are Cd, Hg, Tl, Sb and As for the Au-Ag deposits and In, Ga, Bi, As, Sb, W and Sn for the base-metal deposits (Table 1.22, Shikazono and Shimizu, 1992). Minerals containing Cu, Ag, Sb and As are common in both types of deposits. They are thus not included in Table 1.22. [Pg.180]

Cathles, L.M. (1986) The geologic solubility of gold from 200-300°C, and its implications for gold-base metal ratios in vein and stratiform deposits. In Clark, L. (ed.). Gold in Western Shield. Can. Inst. Min. Metall. Spec., 38, 187-210. [Pg.269]


See other pages where Metal ratios is mentioned: [Pg.445]    [Pg.92]    [Pg.398]    [Pg.43]    [Pg.436]    [Pg.317]    [Pg.250]    [Pg.251]    [Pg.426]    [Pg.938]    [Pg.127]    [Pg.138]    [Pg.389]    [Pg.431]    [Pg.472]    [Pg.377]    [Pg.159]    [Pg.168]    [Pg.199]    [Pg.201]    [Pg.202]    [Pg.207]    [Pg.207]    [Pg.162]    [Pg.383]    [Pg.117]    [Pg.118]    [Pg.119]    [Pg.125]    [Pg.472]    [Pg.333]    [Pg.430]    [Pg.158]    [Pg.20]    [Pg.88]    [Pg.183]    [Pg.361]    [Pg.385]    [Pg.385]   
See also in sourсe #XX -- [ Pg.83 , Pg.180 , Pg.183 , Pg.385 ]




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