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91.
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
92.
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
93.
94.
95.
Luciano De Vito 《Archive for Rational Mechanics and Analysis》1959,3(1):60-81
Memoria presentata da G. Fichera 相似文献
96.
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
97.
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
98.
99.
Luciano Biasini 《Annali dell'Universita di Ferrara》1971,16(1):115-128
Sommario Sono presentate diverse formule, di ordine elevato, che approssimano l'operatore di Laplace e che sono particolarmente vantaggiose
quando vengono impiegate per la soluzione numerica della equazione di Poisson in due dimensioni.
Lavoro eseguito nell'ambito del Consiglio Nazionale delle Ricetche. 相似文献
In this paper some high-order difference approximations to Poisson's equation in two dimensions are given It is shown that many formulas are available for practical calculations; their appropriate use associated with the process of repeating the solution on a finer mesh is a faster and more accurate method of improving the numerical solution.
Lavoro eseguito nell'ambito del Consiglio Nazionale delle Ricetche. 相似文献
100.