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961.
962.
Solubilization of water and aqueous NaCl in mixed reverse micelles (RMs) comprising sodium bis(2‐ethylhexyl) sulfosuccinate (AOT), and polyoxyethylene (20) sorbitan trioleate or polyoxyethylene (20) sorbitan monooleate has been studied at different compositions (Xnonionic = 0–1.0) at a total surfactant concentration, ST = 0.10 × 103 mol m?3 in biocompatible oils of different chemical structures; viz., ethyl oleate (EO), isopropyl myristate (IPM) and isopropyl palmitate (IPP) at 303 K. The enhancement in water solubilization (i.e., synergism) has been evidenced by the addition of nonionic surfactant to dioctyl sulfosuccinate/oil(s)/water systems. Addition of NaCl in these systems at different Xnonionic enhances their solubilization capacities further until a maximum, ωNaCl,max is reached. ωNaCl,max and [NaCl]max (concentration at which maximization of NaCl solubilization occurs) depend on type of nonionic surfactant, its content (Xnonionic) and oil. A new solubilization efficiency parameter (SP*water or SP*NaCl) has been proposed to compare solubilization phenomena in these oils. The energetic parameters of the desolubilization process of water or aqueous NaCl in single and mixed RMs have been estimated. Energetically, the water dissolution process in oil has been found to be more exothermic as well as more organized in IPP. Overall, the dissolution of water and aqueous NaCl in mixed RMs is entropically driven process. Conductance behavior of these systems in the presence of NaCl has been investigated under different [NaCl] at 303 K. An attempt has been made to give an insight to the mechanism of solubilization phenomena, percolation in conductance and microstructures vis‐à‐vis role of biocompatible oils in these systems. 相似文献
963.
S. Cecchi T. Etzelstorfer E. Müller A. Samarelli L. Ferre Llin D. Chrastina G. Isella J. Stangl J. M. R. Weaver P. Dobson D. J. Paul 《Journal of Electronic Materials》2013,42(7):2030-2034
Ge/SiGe multiple quantum wells are presented as efficient material for room-temperature thermoelectric generators monolithically integrated onto silicon. We have deposited and characterized 10-μm-thick heterostructures engineered for lateral devices, in which both heat and current flow parallel to the multilayer. In this paper we investigate in detail the structural and interface quality by means of x-ray diffraction and transmission electron microscopy. Thermoelectric measurements, giving a figure of merit of 0.04 to 0.08, together with mobility spectra and defect analysis suggest possibilities of even higher efficiency. Nevertheless, the high power factor of 2 mW/K2m to 6 mW/K2m is promising for applications. 相似文献
964.
Transition zones between structures as bridges or box culverts frequently present higher degradation rates compared to the remaining railway. This paper presents a numerical model for the dynamic loads on the ballast caused by trains passing a transition. The model was validated with field data obtained from an extensive field survey conducted in two transition zones in the Netherlands. Results show that the forces on the ballast vary significantly both in time and space on a transition, especially with the appearance of voids under the sleepers. Implications of the results on the long-term behaviour of transition zones are presented. 相似文献
965.
966.
Wasylyshyn Christina; Verhaeghen Paul; Sliwinski Martin J. 《Canadian Metallurgical Quarterly》2011,26(1):15
A meta-analysis of 26 published articles (with 36 independent participant groups) was conducted to analyze the relationship between task-switching effects and aging. Latency served as the dependent measure. Multilevel modeling was used to test for additive and multiplicative complexity effects in local and global switch costs. Global task switching was found to add 1 or more stages to processing and resulted in a marked age deficit. Local task-switching costs, on the other hand, showed a multiplicative complexity effect but no specific attention-related age deficits. Cueing or switch predictability did not affect age differences. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
967.
968.
Image acquisition technology is improving very fast from a performance point of view. However, there are physical restrictions that can only be solved using software processing strategies. This is particularly true in the case of super resolution (SR) methodologies. SR techniques have found a fertile application field in airborne and space optical acquisition platforms. Single-frame SR methods may be advantageous for some remote-sensing platforms and acquisition time conditions. The contributions of this article are basically two: (1) to present an overview of single-frame SR methods, making a comparative analysis of their performance in different and challenging remote-sensing scenarios, and (2) to propose a new single-frame SR taxonomy, and a common validation strategy. Finally, we should emphasize that, on the one hand, this is the first time, to the best of our knowledge, that such a review and analysis of single SR methods is made in the framework of remote sensing, and, on the other hand, that the new single-frame SR taxonomy is aimed at shedding some light when classifying some types of single-frame SR methods. 相似文献
969.
970.
Christian J. Cyron Jean-Jacques Marigo Paul Sicsic 《International Journal of Fracture》2014,187(1):51-75
This paper studies the initiation of cohesive cracks in the thermal shock problem through a variational analysis. A two-dimensional semi-infinite slab with an imposed temperature drop on its free surface is considered. Assuming that cracks are periodically distributed and orthogonal to the surface, at short times we show that the optimum is a distribution of infinitely close cohesive cracks. This leads us to introduce a homogenized effective behavior which reveals to be stable for small times, thanks to the irreversibility. At a given loading cracks with a non-cohesive part nucleate. We characterize the periodic array of these macro-cracks between which the micro-cracks remain. Finally, for longer times, the cohesive behavior converges towards that from Griffith’s evolution law. Numerical investigations complete and quantify the analytical results. 相似文献