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131.
The use of new food grade polysaccharides (mucilage) obtained from Hibiscus esculentus and Trigonella foenum graceum,commonly called Okra and Fenugreek,respectively,as flocculants was described.These polysaccharides were used for removal of solids (suspended solids (SS) and total dissolved solids (TDS)) and dyes from real textile effluents and aqueous solutions of different class of synthetic dyes.Influences of varying polysaccharide concentration,contact time and pH on removal of pollutant from the text...  相似文献   
132.
We describe the construction of a model complex of the cellobiohydrolase I (CBH I) cellulase from Trichoderma reesei bound to a cellulose microfibril in an aqueous environment for use in molecular dynamics (MD) simulations. Preliminary characterization from the initial phases of an MD simulation of this complex is also described. The linker sequence between the two globular domains was found to be quite flexible, and the oligosaccharides bound to this linker were found to prefer to be splayed like the spokes in a wheel due to their hydration requirements. The overall conformations of the two globular domains remained stable in the simulations, although both underwent changes in their orientations.  相似文献   
133.
One of the main question faced by the large eddy simulation(LES) users is, why dynamic model works? Many authors have tried to answer this question with little sucess. In the present work we would like to show the insensitiveness of the dynamic model to the externaly introduced variation in the model coefficent, which proves the robustnessof the model. Analytical and physical reasoning for this behaviour is given by simulating the fully developed channel flow case. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
134.
In this paper, the effect of angle inclination at the interface of a viscous fluid and thermoelastic micropolar honeycomb solid due to inclined load is investigated. The inclined load is assumed to be a linear combination of normal load and tangential load. Laplace transform with respect to time variable and Fourier transform with respect to space variable are applied to solve the problem. Expressions of stresses, temperature distribution, and pressures in the transformed domain are obtained by introducing potential functions. The numerical inversion technique is used to obtain the solution in the physical domain. The frequency domain expressions for steady state are also obtained with appropriate change of variables. Graphic representations due to the response of different sources and changes of angle inclination are shown. Some particular cases are also discussed.  相似文献   
135.
136.

Background  

Protein kinase D (PKD) has been implicated in a wide range of cellular processes and pathological conditions including cancer. However, targeting PKD therapeutically and dissecting PKD-mediated cellular responses remains difficult due to lack of a potent and selective inhibitor. Previously, we identified a novel pan-PKD inhibitor, CID755673, with potency in the upper nanomolar range and high selectivity for PKD. In an effort to further enhance its selectivity and potency for potential in vivo application, small molecule analogs of CID755673 were generated by modifying both the core structure and side-chains.  相似文献   
137.
We prove that the 2-category of small abelian categories with exact functors is anti-equivalent to the 2-category of definable additive categories. We define and compare sheaves of localisations associated to the objects of these categories. We investigate the natural image of the free abelian category over a ring in the module category over that ring and use this to describe a basis for the Ziegler topology on injectives; the last can be viewed model-theoretically as an elimination of imaginaries result.  相似文献   
138.
The influence of the alkyl group substituents on the ultrasonic degradation of poly (alkyl methacrylate)s, namely poly (methyl methacrylate) (PMMA), poly (ethyl methacrylate) (PEMA) and poly (butyl methacrylate) (PBMA) was studied. The rate coefficient increased with an increase in the number of carbon atoms in the alkyl group: thus the order of degradation was PBMA>PEMA>PMMA. This was attributed to the scission of the main chain, which increases with the length of the side chain. The ultrasonic degradation of PBMA was investigated in various solvents, at different temperatures and at different ultrasound intensities. The degradation rate coefficients increased logarithmically with the decrease in vapor pressure and increased linearly with an increase in viscosity of the solvent and ultrasound intensity. The effect of three different initiators, benzoyl peroxide (BPO), dicumyl peroxide (DCP) and azo-bisisobutyronitrile (AIBN) on the ultrasonic degradation of PBMA was also studied. The degradation of the polymer decreased in the presence of the initiator. A continuous distribution model was developed for the radical mechanism involved in degradation and was used to determine the degradation rate coefficients of PBMA in presence of initiator. The model indicated that the degradation rate coefficient of the interaction of the PBMA radical with the initiator is independent of the dissociation constant of the initiator.  相似文献   
139.
The synthesis and characterisation are carried on liquid crystalline (LC) p-dodecyloxy benzoic acid (12OBA) with 1 and 2 wt% for PdCl2 nanoparticles dispersion. Further, characterizations are carried out by different spectroscopic techniques like X-ray diffraction spectrometric studies, scanning electron microscopy, Fourier transform infrared and differential scanning calorimetry (DSC). Textural determinations of the synthesised compounds are recorded by using polarising optical microscope (POM) attached with a hot stage and camera. The results show that the dispersion of PdCl2 nanoparticles in 12OBA exhibits Nematic phases as same as the pure 12OBA with reduced clearing temperature as expected. Further, the nematic thermal ranges are quenched and the smectic C thermal range has been increased while performing both DSC and POM with the dispersion of 1 wt% PdCl2 nanoparticles. Size dependence on bonding nature with LC compounds is established.  相似文献   
140.
Cholesteryl oleate present as a neutral lipid in low‐density lipoprotein has been speculated to be a biomarker for atherosclerosis. Methods which are at hand for the quantification of cholesteryl oleate are either costly or entail the use of radioactive compounds. Charring of TLC plates has been used to identify cholesteryl esters for a long time but has never been applied to quantification of cholesteryl esters in biological matrices. Here, we report a novel method based on planar chromatography for the analysis of the products of the acyl CoA–cholesterol acyltransferase (ACAT) assay, viz. cholesteryl esters. Using silica gel 60 F254 as stationary phase, compounds were spotted on the plate and run using a solvent system comprising n‐hexane–diethyl ether–glacial acetic acid (90:10:1, v/v/v). The plates were developed by dipping in anisaldehyde–sulfuric acid reagent and were scanned at 546 nm for quantification. The developed method shows good linear relationship in the concentration range of 100–500 ng/band with a correlation coefficient (r) value of 0.9996. The method was validated for accuracy, precision and robustness. Percentage recovery of the method was found to be in the range 96.88–103.01% with intra‐ and inter‐day precision analysis yielding <2% relative standard deviation at nominal concentrations for analysis. The limits of detection and quantification were found to be 6.45 and 19.54 ng, respectively. The method was validated for robustness by making deliberate changes in mobile phase composition, volume and temperature of analysis, and the standard deviations of peak areas for these intentional changes were found to be 1.07, 1.02 and 1.30 respectively. The method was applied to the estimation of cholesteryl esters in plasma samples from patients diagnosed with hypercholesterolemia. No interferences were found from the biological matrices used in the assay. The proposed method could be of immense potential for estimation of cholesteryl oleate as a marker of ACAT activity, for screening of ACAT inhibitors in drug discovery process and in the prognosis of atherosclerosis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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