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991.
Vesna Najdanovic-Visak José N. Canongia Lopes Zoran P. Visak J. Trindade Luís P. N. Rebelo 《International journal of molecular sciences》2007,8(8):736-748
The salting-out effect produced by the addition of potassium phosphate, K3PO4 to aqueous solutions of water-miscible ionic liquids, viz. 1-ethyl-3-methylimidazolium ethyl sulfate, 1-butyl-3-methylimidazolium methyl sulfate, or 1-alkyl-3-methylimidazolium chloride (alkyl = butyl, octyl or decyl) is investigated. The effects are analyzed using both the corresponding temperature–composition pseudo-binary and composition ternary phase diagrams. Different regions of liquid-liquid and solid-liquid phase demixing are mapped. The phase behavior is interpreted taking into account the complex and competing nature of the interactions between the ionic liquid, the inorganic salt and water. In the case of solutions containing 1-octyl- or 1-decyl-3-methylimidazolium chloride, the smaller magnitude of the salting-out effects is explained in terms of the possibility of self-aggregation of the ionic liquid. 相似文献
992.
Comments on K. J. Gergen's (see record 1986-00014-001) rejection of the empiricist claim that observation can or should determine whether statements about the world are accepted by science and his postulation that science is a social activity that can be analyzed in terms of social concepts. The present author delineates several theoretical options that are available to anti-empiricists and sociologs and discusses difficulties associated with less plausible options. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Jorge Laine Joaquin Brito Francisco Severino Germán Castro Patricia Tacconi Simón Yunes José Cruz 《Catalysis Letters》1990,5(1):45-54
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst. 相似文献
994.
995.
Shapes provide a rich set of clues on the identity and topological properties of an object. In many imaging environments, however, the same object appears to have different shapes due to distortions such as translation, rotation, reflection, scaling, or skewing. Further, the order by which the object's feature points are scanned changes, i.e., the order of the pixels may be permuted. Relating two-dimensional shapes of the same object distorted by different affine and permutation transformations is a challenge. We introduce a shape invariant that we refer to as the intrinsic shape of an object and describe an algorithm, BLAISER, to recover it. The intrinsic shape is invariant to affine-permutation distortions. It is a uniquely defined representative of the equivalence class of all affine-permutation distortions of the same object. BLAISER computes the intrinsic shape from any arbitrarily affine-permutation distorted image of the object, without prior knowledge regarding the distortions or the undistorted shape of the object. The critical step of BLAISER is the determination of the shape orientation and we provide a detailed discussion on this topic. The operations of BLAISER are based on low-order moments of the input shape and, thus, robust to error and noise. Examples illustrate the performance of the algorithm. 相似文献
996.
G. Delaplace R. K. Thakur L. Bouvier C. Leprêtre C. Ilnyzckyj C. André C. Nouar 《化学工程与技术》2008,31(2):231-236
In an effort to better understand the homogeneity of heat treatment of foodstuffs in holding tubes, the cumulative residence time distribution function is derived for a Herschel‐Bulkley fluid from fully developed laminar flow in a straight circular tube under isothermal conditions when diffusional effects are negligible. The proposed analytical solution can be reduced to solutions for Newtonian, shear‐thinning, dilatant, Bingham fluids by setting particular rheological parameters, and consequently, it is possible to successfully explain the dependence of residence time distribution on fluid properties for almost all of the rheological models used for time‐independent purely viscous fluids. 相似文献
997.
Jacques Demongeot Nicolas Glade Andr��s Moreira Laurent Vial 《International journal of molecular sciences》2009,10(8):3420-3441
A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial) origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences) that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes) and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells. 相似文献
998.
Ana Júlia C. da Silva Fred A.R. Nogueira Odilon A.S. Araújo José Ginaldo da Silva Junior Marcelo Navarro Josealdo Tonholo Adriana S. Ribeiro 《Synthetic Metals》2009,159(21-22):2269-2272
12-Pyrrol-1′-yl dodecanoic acid was prepared and electrochemically polymerized on ITO electrodes by three different methods. The electrochemical and morphological properties of poly(12-pyrrol-1′-yl dodecanoic acid) films were investigated by cyclic voltammetry, galvanostatic charge–discharge curves and AFM, which characteristics varied as function of deposition method. Films deposited by potentiodynamic and galvanostatic methods showed capacitive properties and are promising for application in polymeric capacitors. 相似文献
999.
Rodrigo S. da Silveira Andréa M. de Oliveira Sibele B. C. Pergher Victor Teixeira da Silva Ione M. Baibich 《Catalysis Letters》2009,129(3-4):259-265
Palladium and/or molybdenum catalysts supported on mordenite were prepared and characterized by XRD, UV–vis, DRS, textural properties analysis, TPR, TPD and chemical analysis. The Mo-catalyst rapidly deactivated after the first minutes reaction. The Pd-catalysts were active in the NO decomposition reactions. The incorporation of Mo in the Pd-catalysts improved their catalytic properties. 相似文献
1000.