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41.
The modified quasi-chemical model in the pair approximation for short-range ordering (SRO) in liquids is extended to solutions with two sublattices. Short-range ordering of nearest-neighbor pairs is treated, and the effect of second-nearest-neighbor (SNN) interactions upon this ordering is taken into account. The model also applies to solid solutions, if the number of lattice sites and coordination numbers are held constant. It may be combined with the compound-energy formalism to treat a wide variety of solution types. A significant computational simplification is achieved by formally treating the nearest-neighbor pairs as the “components” of the solution. The model is applied to an evaluation/optimization of the phase diagram of the Li,Na,K/F,Cl,SO4 system. 相似文献
42.
Kausik Chattopadhyay Pinaki Mandal Patrice Lerouge Azeddine Driouich Pradyot Ghosal Bimalendu Ray 《Food chemistry》2007,104(3):928-935
Heteroglycan and xyloglucan rich fractions were extracted from Indian samples of Enteromorpha compressa in 25% yield by sequential extractions with water and alkali. This heteroglycan is sulfated and has an apparent molecular mass of 55 kDa. Chemical structural analysis of this polysaccharide revealed a branched structure having 1,4- and 1,2,4-linked rhamnose 3-sulphate, 1,4-linked glucose, 1,3- and 1,6- linked galactose, 1,4- and terminally linked glucuronic acid and 1,4-linked xylose partially sulfated on O-2. Chemical and spectroscopic analysis showed that the 4-M KOH extracted hemicellulosic fraction contained an unusual β-(1,4)-linked linear xyloglucan. Enzyme hydrolysis and analysis of the resulting fragments by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) showed that this linear polymer contained partially sulfated Glc3Xyl2 or Glc4Xyl2 as oligomeric building subunits. 相似文献
43.
Carole Marques Ludovic D’auria Patrice D. Cani Chiara Baccelli Raoul Rozenberg Nike L. Ruibal-Mendieta Géraldine Petitjean Dominique L. Delacroix Joëlle Quetin-Leclercq Jean-Louis Habib-Jiwan Marc Meurens Nathalie M. Delzenne 《Food chemistry》2007,100(3):1265-1271
The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt (Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat (Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food. 相似文献
44.
The parallelization of many algorithms can be obtained using space-time transformations which are applied on nested do-loops
or on recurrence equations. In this paper, we analyze systems of linear recurrence equations, a generalization of uniform
recurrence equations. The first part of the paper describes a method for finding automatically whether such a system can be
scheduled by an affine timing function, independent of the size parameter of the algorithm. In the second part, we describe
a powerful method that makes it possible to transform linear recurrences into uniform recurrence equations. Both parts rely
on results on integral convex polyhedra. Our results are illustrated on the Gauss elimination algorithm and on the Gauss-Jordan
diagonalization algorithm.
This work was partially funded by the French Coordinated Research ProgramC
3 and by a Grant from the SOREP company 相似文献
45.
46.
Tischenkel Nancy J.; Saab Patrice G.; Schneiderman Neil; Nelesen Richard A.; Pasin Rosemary DeCarlo; Goldstein David A.; Spitzer Susan B.; Woo-Ming Rex; Weidler Donald J. 《Canadian Metallurgical Quarterly》1989,8(5):503
Cardiovascular and hormonal responses to a structured interview, an electronic video game, a cold pressor test, and exercise on a bicycle ergometer were assessed in 83 normotensive Black and White men and women (aged 25–44 yrs). Black Ss showed significantly greater diastolic blood pressure (DBP) responses than White Ss during the cold pressor test, which were not accounted for by an increase in plasma catecholamines. Exercise produced reliably greater systolic blood pressure (SBP) increases in Black women than in Black men or White women. Men showed significantly greater SBP and DBP changes than women during the video game. The pattern of physiological reactivity elicited by challenge may be related to the Ss' race and sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Marcin Idczak Dominique Groleau Patrice Mestayer Jean-Michel Rosant Jean-François Sini 《Building and Environment》2010
This paper presents a validation of the thermo-radiative model SOLENE and its application for analysing the street canyon energy balance. The validation data were selected from the temperature and radiation measurements obtained during the JAPEX campaign, previously described by Idczak et al. [16]: a set of four lines of steel containers buildings composing three parallel street canyons at an approximate 1:5 scale. Reference weather data and micrometeorological conditions within the canyon were measured. Numerical simulations were carried out using the meteorological measurements as model inputs. The simulated surface temperatures and radiation fluxes are compared with the measurements for a full week period, with a focus on a day with clear sky conditions. The street canyon energy balance analysis demonstrates that the most energetic surface was the street ground due to its thick surface layer of tar-coated gravels while the walls had a low heat capacity. The thermal radiation balance was negative for all canyon surfaces. The sensible heat was transferred mainly from the canyon surfaces to the ambient air, but also from the air to the ground in the morning. The effective albedo of the canyon had a diurnal value of 0.20–0.25, but dropped to 0.10 in the afternoon when the ground strongly transformed the direct and reflected solar radiation into sensible heat. This narrow street configuration enhanced solar radiation absorption and longwave radiation trapping. 相似文献
48.
Jian Wang Pierre Hudon Dmytro Kevorkov Patrice Chartrand In-Ho Jung Mamoun Medraj 《Journal of Phase Equilibria and Diffusion》2014,35(3):284-313
Phase equilibria in the Mg-rich region of the Mg-Sn-Ag ternary system were determined by quenching experiments, differential scanning calorimetry, electron probe micro-analysis, and X-ray diffraction techniques. No ternary compounds were found in the studied isothermal sections. A critical evaluation of the available experimental data and a thermodynamic optimization of the Mg-Sn-Ag-In quaternary system were carried out using the calculation of phase diagrams method. The modified quasichemical model in the pair approximation was used for the liquid solution, which exhibits a high degree of short-range order. The solid phases were modeled with the compound energy formalism. All available and reliable experimental data were reproduced within experimental error limits. A self-consistent thermodynamic database was constructed for the Mg-Sn-Ag-In quaternary system, which can be used as a guide for Mg-based alloys development. 相似文献
49.
A fast and exact procedure for the numerical synthesis of stationary multivariate Gaussian time series with a priori prescribed and well controlled auto- and cross-covariance functions is proposed. It is based on extending the circulant embedding technique to the multivariate case and can be viewed as a modification and variation around the Chan and Wood algorithm proposed earlier to solve the same problem. The procedure is shown to yield time series possessing exactly the desired covariance structure, when sufficient conditions are satisfied. Such conditions are discussed theoretically and examined on several examples of multivariate time series models. Issues related to prescribing a priori the spectral structure rather than the covariance one are also discussed. Matlab routines implementing this procedure are publicly available at http://www.hermir.org. 相似文献
50.
Sandrine Duluard Aude Paillassa Laurent Puech Philippe Vinatier Viviane Turq Patrick Rozier Pascal Lenormand Pierre-Louis Taberna Patrice Simon Florence Ansart 《Journal of the European Ceramic Society》2013,33(6):1145-1153
NaSICON-type lithium conductor Li1.3Al0.3Ti1.7(PO4)3 (LATP) is synthesized with controlled grain size and composition using solution chemistry. After thermal treatment at 850 °C, sub-micronic crystallized powders with high purity are obtained. They are converted into ceramic through Spark Plasma Sintering at 850–1000 °C. By varying the processing parameters, pellet with conductivities up to 1.6 × 10?4 S/cm with density of 97% of the theoretical density have been obtained. XRD, FEG-SEM, ac-impedance and Vickers indentation were used to characterize the products. The influence of sintering parameters on pellet composition, microstructure and conductivity is discussed in addition to the analysis of the mechanical behavior of the grains interfaces. 相似文献