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991.
Using a conduction calorimeter the specific heat critical behaviour of a TGS crystal has been measured. The ranges of the deviations from the classical behaviour below and above the transition point are 1 and 20 K respectively. These deviations seem to be well related to LK theory predictions. In a range of 0.1 K below the transition point thermal hysteresis appears which does not depend on the measuring temperature rate. The same behaviour is obtained with the sample at atmospheric pressure and under a high vacuum. 相似文献
992.
High pressure treatment is a mild treatment concerning the nutritional characteristics: for instance vitamins content is very few affected by high-pressure treatment. But the impact of high-pressure on protein digestibility remains poorly understood. This work presents effect of high-pressure treatment on in vitro digestibility of meat and lupin proteins. Two high-pressure conditions (200 and 500 MPa 10 min.) and a heat treatment of 95 °C, 30 min were studied. In vitro digestibility was evaluated with a pepsin reaction. Results show than for both type of proteins, samples pressurised at 500 MPa were the most hydrolysed. Meat proteins were less hydrolysed than control either after heat or 200 MPa treatment. Lupin proteins where more hydrolysed than control after heat or 200 MPa treatment. Thus we revealed that high-pressure treatment presents an effect on the in vitro digestibility of proteins, opening a new perspective of investigations. 相似文献
993.
994.
P. Del Moral 《随机分析与应用》2013,31(3):519-575
Abstract This article is concerned with strong propagations of chaos properties in Moran's type particle interpretations of continuous time Feynman–Kac formulae. These particle schemes can also be seen as approximating models of simple generalized spatially homogeneous Boltzmann equations. We provide a simple and original semigroup analysis based on empirical tensor measures combinatorics properties, martingales techniques, and coupling arguments. We also design a general and abstract framework without any topological assumption on the state space. This yields a natural way to analyze the propagations of chaos properties for interacting particle models on path space. Applications to genealogical type particle algorithms for the nonlinear filtering and smoothing problem are also discussed. 相似文献
995.
We propose deformations of inherent structures as a suitable tool for detecting structural changes underlying the onset of cooperativity in supercooled liquids. The non-affine displacement (NAD) field resulting from the applied deformation shows characteristic differences between the high temperature liquid and supercooled state, which are typically observed in dynamic quantities. The average magnitude of the NAD is very sensitive to temperature changes in the supercooled regime and is found to be strongly correlated with the inherent structure energy. In addition, the NAD field is characterized by a correlation length that increases upon lowering the temperature towards the supercooled regime. 相似文献
996.
Lima-Neto RG Cavalcante NN Srivastava RM Mendonça Junior FJ Wanderley AG Neves RP dos Anjos JV 《Molecules (Basel, Switzerland)》2012,17(5):5882-5892
1,2,3-Triazoles have been extensively studied as compounds possessing important biological activities. In this work, we describe the synthesis of ten 2-(1-aryl-1H-1,2,3-triazol-4-yl)propan-2-ols via copper catalyzed azide alkyne cycloaddition (CuAAc or click chemistry). Next the in vitro antifungal activity of these ten compounds was evaluated using the microdilution broth method against 42 isolates of four different Candida species. Among all tested compounds, the halogen substituted triazole 2-[1-(4-chlorophenyl)-1H-(1,2,3)triazol-4-yl]propan-2-ol, revealed the best antifungal profile, showing that further modifications could be done in the structure to obtain a better drug candidate in the future. 相似文献
997.
Landau a défini g(n) comme l’ordre maximal d’un élément du groupe symétrique
\mathfrakSn\mathfrak{S}_{n}. Nous donnons plusieurs estimations du plus grand facteur premier P
+(g(n)) de g(n). 相似文献
998.
Del Rosal I Poteau R Maron L 《Dalton transactions (Cambridge, England : 2003)》2011,40(42):11211-11227
The influence of the grafting mode of a borohydride lanthanum complex on a silica surface on the energetic (kinetic and thermodynamic parameters) of the Ring Opening Polymerization (ROP) reaction of ε-caprolactone has been studied in the framework of density functional theory (DFT). For all considered grafted catalysts (monografted, bigrafted, or bigrafted after breaking of a Si-O-Si bridge), it is shown that lanthanum borohydride grafted complexes are efficient in lactone polymerization. Moreover, the reaction pathways (leading to a -CH(2) OBH(2) chain end) are predicted to be energetically similar for the three grafting modes, indicating that all grafted modes can account for the activity for silica treated at 700 °C. The catalytic activity of the grafted complexes is also very similar to that of the homogeneous complexes. 相似文献
999.
A synthetic approach to the C17-benzene ansamycins via metal catalyzed C-C coupling is described. Key bond formations include direct iridium catalyzed carbonyl crotylation from the alcohol oxidation level followed by chelation-controlled Sakurai-Seyferth dienylation to form the stereotriad, which is attached to the arene via Suzuki cross-coupling. The diene-containing carboxylic acid is prepared using rhodium catalyzed acetylene-aldehyde reductive C-C coupling mediated by gaseous hydrogen. Finally, ring-closing metathesis delivers the cytotrienin core. 相似文献
1000.
Vasapollo G Mele G Sole RD Pio I Li J Mazzetto SE 《Molecules (Basel, Switzerland)》2011,16(7):5769-5784
Cardanol, a well known hazardous byproduct of the cashew industry, has been used as starting material for the synthesis of useful differently substituted "cardanol-based" porphyrins and their zinc(II), copper(II), cobalt(II) and Fe(III) complexes. Novel composites prepared by impregnation of polycrystalline TiO? powder with an opportune amount of "cardanol-based" porphyrins, which act as sensitizers for the improvement of the photo-catalytic activity of the bare TiO?, have been used in the photodegradation in water of 4-nitrophenol (4-NP), which is a toxic and bio-refractory pollutant, dangerous for ecosystems and human health. 相似文献