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L. Gillo S. E. Golbreich T. Nagoshi I. Nakagawa C. S. Piper W. C. Campbell Marion I. Hanna L. Palfray C. Rocchi R. del Monte R. Lechner M. Roß L. A. Ynalvez H. Lecoq Th. A. G. Haanappel Thérèse Jullig J. Barbière A. Lecco L. Lilic und P. M. Heertjes 《Fresenius' Journal of Analytical Chemistry》1943,125(3-4):133-137
Ohne Zusammenfassung 相似文献
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The transformation of chemically bound gold into metallic gold during industrial scale roasting of an arsenical gold ore concentrate from the Fairview Mine, Eastern Transvaal, has been studied quantitatively by197Au Mössbauer spectroscopy. The iron compounds in the concentrate, mainly FeAsS and FeS2 and their transformations during roasting have been studied by57Fe Mössbauer spectroscopy. The bound gold is found to convert into the metal in parallel to the decomposition of FeAsS and the increase in cyanide leachability. this shows that the refractory character of the ore is caused by the chemical bonding of the gold rather than by the physical inclusion of small, discrete metallic particles in the matrix of FeAsS or FeS2. The ratio of thef-factors of gold bound in the FeAsS component of a refractory ore and of metallic gold was determined to bef(Au:FeAsS)/f(Au)=1.48±0.09. 相似文献
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Cyclometalated Iridium(III) and Rhodium(III) Complexes Containing Naphthyridine Ligands: Synthesis,Characterization and Biological Studies 下载免费PDF全文
The synthesis, crystal structure, and biological activity of new bis‐cyclometalated compounds [M(ptpy)2(4‐chloro‐2‐methyl‐1,8‐naphthyridine)]PF6 [M = Rh ( 1 ); M = Ir ( 2 ); ptpy = 2‐(p‐tolyl)pyridinato] and [M(ptpy)2(2‐methyl‐1,8‐naphthyridine)]PF6 [M = Rh ( 3 ); M = Ir ( 4 )] are described. The new compounds were prepared by the reaction of [{M(μ‐Cl)(ptpy)2}2] (M = Rh, Ir) with the corresponding naphthyridine ligands. The molecular structures of compounds 1 , 3 , and 4 were confirmed by single‐crystal X‐ray diffraction studies. 相似文献
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Bernard Riss Marion Garreau Prisca Fricero Patricia Podsiadly Nicolas Berton Sophie Buchter 《Tetrahedron》2017,73(23):3202-3212
The absolute configuration of bisabolangelone has been established by an eleven step total synthesis of the corresponding TMS protected antipode starting from (R)-(+)-pulegone. Comparison of the TMS-derivatives by GC on a chiral column, allowed us to assign the absolute configuration of the synthetic compound and thus of the corresponding natural product. The latter has been confirmed by the Mosher's ester analysis of the known secondary carbinol derivative. 相似文献
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Marion Collinet-Fressancourt Nathalie Azaroual Jean-Marie Aubry Véronique Nardello-Rataj 《Tetrahedron letters》2010,51(50):6531-6534
The kinetic booster effect of dimethylsulfoxide on the chemical generation of singlet oxygen, 1O2, from the disproportionation of hydrogen peroxide catalyzed by molybdate ions in methanol has been evidenced by detection of the IR luminescence of 1O2 at 1270 nm and by 95Mo NMR spectroscopy. DMSO interacts rapidly, through a direct oxygen transfer with the stable tetraperoxomolybdate , leading to DMSO2 and to the unstable triperoxomolybdate , which releases 1O2. The procedure was applied to accelerate the dark singlet oxygenation of β-citronellol and α-terpinene. 相似文献
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