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Water separated from crude oil and wastewater discharge from petroleum oil refineries contains significant quantity of dissolved hydrocarbons. Polycyclic aromatic hydrocarbons (PAHs) are major toxicants in wastewater of refineries. It is difficult to treat wastewater containing PAHs due to their recalcitrant property and low solubility. Conventional techniques for the treatment of wastewater are still a concern of toxicity. Electrochemical oxidation process has been found to be a favorable for treating wastewater. Electrodes with high stability and electrocatalytic activity are important factors for a successful electrochemical oxidation of toxic organics in wastewater. In this study titanium anodes were coated with tin, antimony and iridium oxide mixture from their respective salts by thermal decomposition method. FESEM and XRD used for surface characterization of Ti/SnO2–Sb2O5–IrO2 anode. Quantification of PAHs was done using GC–MS. Results confirm the presence of respective oxides on anode surface. Their electrocatalytic capability was tested for degradation of 16 priority PAHs in aqueous solution. Results reveal the complete degradation of naphthalene, acenaphthylene, acenaphthene and fluorene without using NaCl electrolyte. While in the presence of NaCl naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene were completely removed. About 98% of total PAHs removal was found at all initial pH values 3, 6, and 9 in the presence of electrolyte. Current study will be helpful in improving quality of petroleum industry wastewater containing PAHs. 相似文献
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A mass spectrometric method has been proposed for the determination of the isotopic composition of lithium. It is based upon thermal ionization of LiOH loaded onto a single SiO2-coated Re filament. By this method, stable emissions of Li+ ion have been achieved for an extended period of time. The proposed method is capable of analyzing trace quantities (approximately 40 ng) of Li in the presence of sodium with an uncertainty of +/-0.000 25 (two standard deviations of the mean). 相似文献
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Latent Semantic Kernels 总被引:5,自引:0,他引:5
Nello Cristianini John Shawe-Taylor Huma Lodhi 《Journal of Intelligent Information Systems》2002,18(2-3):127-152
Kernel methods like support vector machines have successfully been used for text categorization. A standard choice of kernel function has been the inner product between the vector-space representation of two documents, in analogy with classical information retrieval (IR) approaches.Latent semantic indexing (LSI) has been successfully used for IR purposes as a technique for capturing semantic relations between terms and inserting them into the similarity measure between two documents. One of its main drawbacks, in IR, is its computational cost.In this paper we describe how the LSI approach can be implemented in a kernel-defined feature space.We provide experimental results demonstrating that the approach can significantly improve performance, and that it does not impair it. 相似文献
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A series of imitation games involving 3-participant (simultaneous comparison of two hidden entities) and 2-participant (direct interrogation of a hidden entity) were conducted at Bletchley Park on the 100th anniversary of Alan Turing’s birth: 23 June 2012. From the ongoing analysis of over 150 games involving (expert and non-expert, males and females, adults and child) judges, machines and hidden humans (foils for the machines), we present six particular conversations that took place between human judges and a hidden entity that produced unexpected results. From this sample we focus on features of Turing’s machine intelligence test that the mathematician/code breaker did not consider in his examination for machine thinking: the subjective nature of attributing intelligence to another mind. 相似文献
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Muhammad Salman Makshoof Athar Umar Farooq Huma Nazir Anam Noor Saba Nazir 《Korean Journal of Chemical Engineering》2013,30(6):1257-1264
The present study concentrated on the use of an agro-waste biodegradable sorghum biomass in its simple and modified forms for the binding of Cr (III) ions. A relatively new method of modification was adopted using urea under microwave irradiation. FTIR analysis showed the presence of oxygen and nitrogen bearing functional groups in unmodified (UMS) and modified (MS) sorghum biomass. The appearance of new bands and shifts in the peaks confirmed the modification. The influence of different process parameters such as the adsorbent dose, solution pH, contact time, agitation speed and initial metal ion concentration was studied thoroughly to evaluate optimum conditions for adsorption. Maximum adsorption for Cr (III) ions occurred at pH 5.0–6.0 using UMS and MS. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models in a non-linear fashion were used to explain the phenomenon. Maximum adsorption capacity was 7.03 and 16.36 mg of Cr (III) per gram of UMS and MS, respectively. Adsorption mechanism was explored by pseudo-first- and pseudo-second-order kinetic models, and it was found that the process followed pseudo-second-order kinetics. Thermodynamic study indicated the process favorability. The study concluded that urea modification under microwave irradiation produces a non-toxic and more effective adsorbent for Cr (III) remediation by inducing new nitrogen bearing functional groups to sorghum biomass. 相似文献
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Empirical evidence suggests that computer self-efficacy plays an important role in one’s acceptance and use of new information technology. Little is however known about the antecedents of computer self-efficacy. This paper reports on a study of 143 non-users of a self-checkout library system available at a large Canadian university which was conducted to investigate the relationships between stable personality traits and gender with computer self-efficacy. Results indicate that four of the five stable personality traits, as measured by the Big-5 factors of personality, contribute to explain computer self-efficacy. Taking gender into account, results show that the traits of neuroticism, extraversion, and agreeableness are significantly related to computer self-efficacy for women but not for men. Implications for research and practice are discussed. 相似文献
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Muhammad K. Khan Weeraya Karnpanit Syed M. Nasar‐Abbas Zill‐e‐ Huma Vijay Jayasena 《International Journal of Food Science & Technology》2015,50(9):2004-2012
Lupin is a nonstarchy grain legume with high protein, dietary fibre and low fat contents. The industrial shift of lupin seed utilisation from feed to food has recently increased the scientific interest to explore its phytochemical composition and biological activities. Lupin seeds contain significant amounts of polyphenols, carotenoids, phytosterols, tocopherols, alkaloids and peptides with antioxidant, antimicrobial, anticarcinogenic and anti‐inflammatory activities. Among polyphenols, genistein and their derivatives (isoflavones) are of great importance because of their phytoestrogenic potential. This comprehensive review will help out the readers in understanding the phytochemicals present in lupin and their benefits. 相似文献
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