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111.
Silas Arandas Monteiro e Silva Michele Fernanda Costa Valarini Marlus Chorilli Stig E. Friberg 《Journal of Dispersion Science and Technology》2014,35(8):1191-1199
Formulations with lyotropic liquid crystals were prepared from a Brazilian nut vegetable oil, guarana extract and combination of sorbitan monooleate (Span 80) and sorbitan monolaurate ethoxylate EO 20 (Tween 20) in the ratio 1:3 (surfactant component) and their physical–chemical aspects and rheological properties were determined. Compositions with liquid crystals were found in the pseudoternary diagram in a surfactant range of 70–90% and polarized light microscopy, small-angle x-ray scattering (SAXS) showed them to be lamellar. The preparations were furthermore characterized rheologically by shear stress shear rate sweeps finding plastic and pseudoplastic behavior without thixotropy. Electric conductivity and pH measurements demonstrated a potential for future application as dermatological delivery system of the active compounds in the Bertholletia excelsa and Paullinia cupana. 相似文献
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116.
Chen B Park JM Ivanov I Tabacchi G Klein ML Parrinello M 《Journal of the American Chemical Society》2002,124(29):8534-8535
Car-Parrinello molecular dynamics simulations have been carried out for aqueous NaOH and KOH solutions under ambient conditions over a wide range of concentrations. From these simulations, we have observed a continuous change of the water structure with added hydroxide, characterized by a significant shift of the second peak of the OO radial distribution functions to shorter distances. At the highest concentration investigated, the normal tetrahedral coordination of pure water is completely missing, a result that is consistent with a recent neutron diffraction experiment. The added hydroxide also gives rise to some unique spectroscopic features, including a "free" O-H stretch, a broadening of the normal water OH stretching band, and a large blue shift of both the librational band and the low-frequency translation. These results are in good agreement with the experimental data. Finally, it was demonstrated that the structural and dynamical behavior is inextricably linked to the formation of compact hydroxide-water complexes. 相似文献
117.
Dellago C Geissler PL Chandler D Hutter J Parrinello M 《Physical review letters》2002,89(19):199601; author reply 199602
118.
We simulate neutral evolution of proteins imposing conservation of the thermodynamic stability of the native state in the framework of an effective model of folding thermodynamics. This procedure generates evolutionary trajectories in sequence space which share two universal features for all of the examined proteins. First, the number of neutral mutations fluctuates broadly from one sequence to another, leading to a non-Poissonian substitution process. Second, the number of neutral mutations displays strong correlations along the trajectory, thus causing the breakdown of self-averaging of the resulting evolutionary substitution process. 相似文献
119.
We compute tensor products of representations of the holomorphic discrete series of a Lie group G, or restrictions to some subgroup G′. A detailed study is done for the case of the conformal group O(4, 2). 相似文献
120.
Michele Ciarletta 《Annali dell'Universita di Ferrara》1979,25(1):9-15
Riassunto In questo lavoro si affrontano i problemi relativi alle restrizioni termodinamiche, imposte dal principio di entropia nella
formulazione di Müller [1], per fluidi con memoria, mediante il metodo dei moltiplicatori di Lagrange.
Lavoro eseguito nell'ambito del G.N.F.M. del C.N.R. 相似文献
Summary In this work Author deals with the problems pertinent to the thermodynamic restrictions, which are due to principle of entropy in the formulation of Müller [1], for fluids with a memory, through the Lagrange multipliers.
Lavoro eseguito nell'ambito del G.N.F.M. del C.N.R. 相似文献