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41.
Guido Barone Giuseppina Castronuouvo Vittorio Elia Maria Teresa Tosto 《Journal of solution chemistry》1986,15(2):199-210
The excess enthalpies of twelve ternary aqueous solutions of alcohols or monosaccharides containing thiourea have been determined by flow microcalorimetry at 25°C. The coefficients of the virial expansion of the excess enthalpies are compared with those reported in the literature for the same ternary solutions containing urea in place of thiourea. The cross-interaction coefficients are positive for the thiourea-alcohol systems and depend on the length and branching of the alkyl chain of the alcohols. On the other hand, they are negative for the thiourea-monosaccharide systems. Thus, thiourea, as urea, can be used as a probe to reveal differences in the behavior of families of solutes characterized by the same functional groups. The results can be interpreted in terms of the relative stabilities of hydration cospheres of hydrophobic or hydrophilic solutes toward a chaotropic agent such as thiourea.Presented at the sixth Italian meeting on Calorimetry and Thermal Analysis (AICAT) held in Naples, December 4–7, 1984. 相似文献
42.
Guido Barone Giuseppina Castronuovo Pompea Del Vecchio Vittorio Elia Maria Teresa Tosto 《Journal of solution chemistry》1988,17(10):925-936
The excess enthalpies of ternary aqueous solutions of biuret with four aliphatic alcohols or four isomeric pentoses have been determined by flow microcalorimetry at 25°C. The coefficients of the virial expansion of the excess enthalpies have been evaluated and compared with those already reported for urea and thiourea with the same alcohols and pentoses used here. For biuret-alcohol systems, the cross coefficients are positive and depend on the length and branching of the alkyl chain of the alcohols. On the contrary, they are negative for biuret-pentose systems. Hence, biuret, as urea and thioura, is able to differentiate the behavior of families of solutes characterized by the same functional groups. The results are interpreted in terms of the relative stabilities of the hydration cospheres of predominantly hydrophobic or predominantly hydrophilic cosolutes. However, hypotheses about the hydration cospheres of the saccharides, which are more complex than those used previously, seem to be necessary to rationalize their complete behavior in water. 相似文献
43.
María D. Hernández-Alonso Juan M. Coronado Javier Soria José Carlos Conesa Vittorio Loddo Maurizio Addamo Vincenzo Augugliaro 《Research on Chemical Intermediates》2007,33(3-5):205-224
Oxidation of free cyanide in aqueous suspensions of three commercial TiO2 specimens, with different anatase crystal size, has been carried out in a batch photoreactor by simultaneously applying ozonation and photocatalysis. Dissolved ozone participates both in homogeneous and catalytic reactions with cyanide; the extents of these two processes are comparable to that of the photodegradation with oxygen. The reactivity results are well described by the Langmuir-Hinshelwood kinetic model, providing the values of the kinetic and equilibrium adsorption constants for the catalytic and photocatalytic reactions contributing to cyanide oxidation. The cyanide concentration decreases faster with time for catalysts with increasing anatase crystal size, being more marked under UV irradiation. EPR studies on gaseous ozone adsorption on the three samples in the dark have shown stronger ozone interactions with Ti4+ and O2? ions of the samples with largest anatase crystal size, leading to the formation of significant signals of Ti3+ and s O??O2 radicals than with the anatase with the lowest crystal size, where ozone was mainly adsorbed on water molecular arrangements covering its surface. The hampering of the ozone and/or cyanide adsorption by the water molecular arrangements covering the surface of the catalyst with the lowest crystal size would justify the low cyanide degradation rate observed for this sample. 相似文献
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This paper concerns with a state of bending for a linear transversely isotropic plate model based on the Mindlin assumption on the displacement. By using appropriate families of line-integral measures, we are able to establish results about the spatial behaviour of transient and steady-state solutions. All the results are obtained under relaxed hypotheses on the positive definiteness of the elasticity tensor. 相似文献
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Frank Roschangar Jianxiu Liu Marine Dufour Vittorio Farina Azad Hossain Heewon Lee Richard Varsolona Pierre Beaulieu Chris H. Senanayake 《Tetrahedron letters》2008,49(2):363-366
A regioselective Larock approach to 3-substituted-2-pyridin-2-ylindoles from 2-alkynylpyridines and 2-iodoanilines is described herein. The unexpectedly high regioselectivity can be rationalized by a combination of steric, coordinative and electronic effects. 相似文献
50.
A variable neighborhood search for the capacitated arc routing problem with intermediate facilities 总被引:2,自引:0,他引:2
Michael Polacek Karl F. Doerner Richard F. Hartl Vittorio Maniezzo 《Journal of Heuristics》2008,14(5):405-423
The capacitated arc routing problem (CARP) focuses on servicing edges of an undirected network graph. A wide spectrum of applications
like mail delivery, waste collection or street maintenance outlines the relevance of this problem. A realistic variant of
the CARP arises from the need of intermediate facilities (IFs) to load up or unload the service vehicle and from tour length
restrictions. The proposed Variable Neighborhood Search (VNS) is a simple and robust solution technique which tackles the
basic problem as well as its extensions. The VNS shows excellent results on four different benchmark sets. Particularly, for
all 120 instances the best known solution could be found and in 71 cases a new best solution was achieved. 相似文献