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1.
Some new amphoteric ion exchangers have been synthesized by condensing salicylic acid, p-hydroxybenzoic acid, sulfosalicylic acid, gallic acid, 3-hydroxy-2-naphthoic acid, β-resorcylic acid, and resacetophenone with epichlorohydrin employing ethylenediamine as a crosslinking agent. Some of the physicochemical properties, such as moisture content, true density, apparent density, void volume fraction, concentration of ionogenic groups, exchange capacity, rate of exchange, pH-titration curves, pK values, isoionic point, thermal stability, oxidation resistance, and swelling behavior in different solvents, have been investigated.  相似文献   
2.
A consumer entering a new bookstore can face more than 250,000alternatives. The efficiency of compensatory and noncompensatory decisionrulesfor finding a preferred item depends on the efficiency of their associatedinformation operators. At best, item-by-item information operators lead tolinear computational complexity; set information operators, on the other hand,can lead to constant complexity. We perform an experiment demonstrating thatsubjects are approximately rational in selecting between sublinear and linearrules. Many markets are organized by attributes that enable consumers toemploya set-selection-by-aspect rule using set information operations. In cyberspacedecision rules are encoded as decision aids.  相似文献   
3.
The importance of fundamental understanding of droplet dynamics and the concomitant implications of wall wettability are critical in the emergent science and technology areas including digital microfluidics and clean energy conversion. In this work, mesoscopic illustration, based on the two-phase lattice Boltzmann model, of droplet dynamics in a microchannel is presented in order to unveil the role of superhydrophobicity and mixed wettability. The impact of critical physicochemical determinants, including capillary number and droplet size, is explored in the context of droplet–wettability interactions. Temporal evolution of wetted length and wetted area for a combination of wettability scenarios is furnished in detail in order to elucidate the droplet displacement dynamics. Capillary number plays an important role with disparate droplet behavioral patterns stemming from superhydrophobic and mixed-wet wall characteristics.  相似文献   
4.
对餐厨垃圾、污水厂污泥以及餐厨垃圾与污泥混合甲烷发酵的产气能力与动力学特性进行了实验分析,餐厨垃圾在中温和高温发酵的产甲烷潜能分别是400和426 mL CH4?gVS−1,经过120℃、20 min蒸煮除油后的餐厨垃圾在中温和高温发酵的产甲烷潜能分别是418和531 mL CH4?gVS−1。经Gompertz模型计算,除油后餐厨垃圾的最大产甲烷速率Rmax比除油前提高了49.8%(中温)和19.0%(高温),但餐厨垃圾中固体有机物的产甲烷速率变化不明显。在餐厨垃圾机械破碎匀浆过程中,部分固体有机物被液化,中、高温发酵产气过程的一级动力学呈现两阶段特征,液相有机物在中温发酵的产甲烷速率(速率常数k = 0.1955 d−1)略快于高温(k = 0.1543 d−1);而固体有机物在高温条件下的产甲烷速率(k = 0.0804 d−1)快于中温(k = 0.0388 d−1)。除油后餐厨垃圾中的固体有机物和污泥高温发酵的产甲烷速率也快于中温发酵,表明高温发酵有利于提高固体有机物的产气速率。污泥的产气潜能较低,产气速率慢,与餐厨垃圾共发酵有助于调节碱度和防止发酵体系的酸化。  相似文献   
5.
Most images may not be sharp and clear due to various reasons like noise interference and is said to be in a blurred condition. Image de-blurring is fundamental in making pictures sharp and useful. Normally, along with the input blurred image, Point Spread Function (PSF) of the original image is required for the process of restoration and de-blurring. In this paper, we introduce a technique for image restoration by Richardson–Lucy algorithm where the optimised PSF is generated by the use of Genetic Algorithm (GA). Use of optimised PSF ensures that our proposed technique does not need the original image for the de-blurring purpose and can be greatly beneficial in the real time scenario cases. The dataset used for the evaluation of the proposed technique are real 3D images and the evaluation metrics used are peak signal-to-noise ratio (PSNR), Second-Derivative like Measure of Enhancement (SDME) and mean squared error (MSE). The technique is compared with existing techniques such as de-convolution method, regularisation filter, Wiener filter and Richardson–Lucy algorithm. From the results, we can observe that our proposed technique has achieved higher PSNR and SDME values and lower MSE values when compared with other techniques. We have achieved average PSNR of 70·94, SDME of 71·46 and MSE of 0·0063. The values obtained show the superior performance of the proposed technique.  相似文献   
6.
A.c. impedance behaviour of MnO2 and doped -MnO2 electrodes in H2SO4 medium was assessed with a view to explaining the mechanism of the discharge behaviour of MnO2 electrodes in 4m H2SO4 electrolyte. The electrodes used in this work appear to be intermediate cases of planar and porous electrodes as the angles, , made by the low frequency part with the real axis are found to be in the range (30–60°). The Nyquist plots and the Randle plots tend to reinforce the observation made by Tye that the capacity yield is essentially diffusion controlled. The depression and flattening of semi-circles observed reveals a link with the heterogeneity of the planar electrode and with the porosity of the pitted electrode. The deviation from a 45° angle made by the low frequency part with the real axis may either be explained by the roughness of the electrode surface or the shallow pores on the surface of the electrodes; in other words due to the difference between the apparent and true surface areas. The double layer capacitance values of the electrodes seem to subsume adsorption capacitances and diffusion factors. Hence, the relative increase in magnitude. The electrodes appear to behave like planar electrodes when 10 µF is introduced into the circuit as a parallel capacitance since angles 0 vary between 40–58°. The undoped -MnO2 electrode, as well as those prepared from Li-MnO2, Ag-MnO2, and I.C.8, appear to be planar electrodes.  相似文献   
7.
This study represents a comprehensive analysis and scientific validation of our ancient knowledge about the ethnopharmacological aspects of cow urine by measuring the lipid peroxidation, radical scavenging, and level of reduced glutathione and catalase activity. Graded doses of cow urine were administered orally to experimentally treated rats. Results of liver and plasma from experimentally treated rats indicated that cow urine reduced the levels of thiobarbituric acid reactive substance significantly in all the treatments (P < 0.01). In vitro experiments with the liver of control and experimentally treated rats were also carried out against cumene hydroperoxide-induced lipid peroxidation. On LCMS analysis, the antioxidant component of cow urine was identified as uric acid (m/z 169.07). The results demonstrate that the cow urine-mediated induction of antioxidant level controls oxidative damage, even after minimal processing, and thus is indicative of its potential as a viable substitute of synthetic antioxidants.  相似文献   
8.
This study focuses on efforts to characterize aging occurring in 15 kV distribution cables in a dry climate. It has been shown that similar changes can be produced by a suitably planned accelerated thermal aging testing in the laboratory. The Arrhenius equation is used for establishing the accelerated aging test parameters. Different modes of statistical analysis namely analysis of variance (ANOVA), Andersen-Darling test for normality, F-test, t-test are performed to validate results from accelerated aging tests with field aging  相似文献   
9.
Proton nuclear magnetic resonance (1H NMR) was used to study the in vivo metabolism of Trypanosoma cruzi, the pathogen causing American trypanosomiasis (Chagas' disease). Three clones were isolated from a strain of T. cruzi (Bolivia strain), The clones I, II and III and the original strain were characterized according to the spectra of their metabolic pathways to test the hypothesis that clonal evolution of T. cruzi has a major impact on biologically relevant properties of this parasite. T. cruzi (Bolivia strain) excreted acetate, alanine, glycerol, and succinate as major end products, in the proportion 6:4:2:2. Comparing the spectra of T. cruzi clones with the original Bolivia strain revealed both quantitative, as well as qualitative differences in the metabolites excreted: the clones I and II, as opposed to the Bolivia strain and clone III, excreted significant quantities of ethanol.  相似文献   
10.
Antecedents of interpersonally directed forms of citizenship and counterproductive behaviors (i.e., interpersonal helping and harming, respectively) have been studied most often under the broad categories of individual differences and job attitudes. Although these behaviors often are exhibited within the confines of interpersonal relationships, the impact of relationship quality and context on such behaviors has been understudied. The present study uses a social networks framework to examine the relational antecedents of interpersonal helping and harming in a sample of 62 members of a college sorority house. Results indicate that relational variables--direct, third-party, and structural or positional characteristics of positive and negative affective networks, and the frequency of voluntary interaction--explain substantial incremental variance (beyond traditional predictors) in helping and harming. Moreover, helping and harming were themselves weakly positively interrelated. Implications for theory and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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