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91.
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93.
Giorgio Gurato Luciano Cavalli G. Giorgio Troilo 《Magnetic resonance in chemistry : MRC》1975,7(11):532-539
From the electrochemical fluorination of the chloride and the fluoride of benzenesulphonic acid, in addition to the main product C6F11SO2F, the side products C5F8(CF3)SO2F, a structural isomer of the main product and C6F10Cl? SO2F are also obtained. The NMR analysis of these products was performed. Chemical shift and coupling constant values were obtained for all the compounds. The NMR parameters of the main product are compared with those of perfluoromethylcyclohexane according to the data of Jolley, Sutcliffe and Walker. From the NMR parameters of C5F8(CF3)SO2F it was possible to demonstrate that substitution on the ring for —SO2F and CF3— is of the 1,3 and not the 1,2 type. 相似文献
94.
We give a lower and an upper estimate for the level of a fluid filtrating through a porous, homogeneous and three-dimensional dam with variable cross-section. 相似文献
95.
Giampaolo Giacomelli Luciano Lardicci Carlo Bertucci Anna Maria Caporusso 《Tetrahedron》1978,34(13):2015-2020
The synthesis and the physical properties of some optically active 1,4-dialkylbuta-1,3-dienes are reported. The synthetic processes employed were essentially stereospecific. NMR, UV and CD spectra of these compounds provide information on the main conformation of the conjugated diene system, which was shown to be s-trans planar. 相似文献
96.
Luciano Lombardo 《Tetrahedron letters》1984,25(2):227-228
The rapid reaction of t-butyldimethylchlorosilane with alcohols catalysed by diisopropylethylamine at room temperature gave high isolated yields of the t-butyldimethylsilyl ethers. 相似文献
97.
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99.
Silvio Aime Luciano Milone Rosanna Rossetti Pier Luigi Stanghellini 《Transition Metal Chemistry》1979,4(5):322-325
Summary
13C-n.m.r. spectra of (-SR)2Fe2(CO)6, (-SR)2Fe2(CO)5P(n-Bu)3 and (-X)2Fe2(CO)6 (X=S or Se) show that the solid state structure is maintained in solution. N.m.r. evidence indicates that two isomeric species, not separable by means of the usual physicochemical methods, are present for (-SPh)2Fe2(CO)6 with an overwhelming predominance of theanti form. The phosphine substitutes a COtrans to the iron-iron bond. For any of the iron chalcogen derivatives examined, variable temperature13C-n.m.r. spectra show that carbonyl exchange occur in one step. The energy barrier for the exchange of carbon monoxide in the phosphine derivative is lower than that in the unsubstituted complex. 相似文献
100.
Toxic metal release in simple leaching tests has been studied in this paper to assess waste behaviour in realistic landfilling scenarios. The waste is a galvanic sludge, raw or cement stabilized. Six different leachants were taken into account: distilled water, CO2-saturated solution, Olsen solution, Mehlich No. 3 solution, acid or alkaline soil circulating solution. Dynamic leaching tests of different duration were used for raw and stabilized waste. The results have shown that, with the exception of Mehlich No. 3 solution, when the waste comes into contact with waters of composition similar to that of the solutions studied, the potential environmental contamination should not be of concern. 相似文献