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71.
Amanda Broska da Cruz Deniz Renata Bachmann Guimarães Valt Maria José Jerônimo de Santana Ponte Haroldo de Araújo Ponte 《化学工程与技术》2020,43(7):1393-1401
Transport phenomena are investigated which are involved in the electrokinetic remediation process used for removing vanadium from deactivated catalysts from oil catalytic cracking that are currently allotted to cement plants and class-I landfills. Variables such as the concentration of electrolyte, electric potential, and applied electric current were evaluated in order to determine the effects produced by electroosmosis, diffusion, hydraulic gradient, and electromigration on the removal of vanadium from the catalyst. It was observed that migration is the most relevant phenomenon in the remediation tests, and for the best remediation condition, the migratory flow accounted for about 87 % of the vanadium removal. 相似文献
72.
Journal of Applied Electrochemistry - In this study, within the defined orthogonal array of Taguchi design, the hydrothermal process parameters have been optimized for fabricating the smallest... 相似文献
73.
Sibel Uzuner Deniz Cekmecelioglu 《International Journal of Food Science & Technology》2015,50(12):2707-2712
This study was undertaken to search for potential use of crude bacterial pectinase enzyme produced from Bacillus subtilis grown on hazelnut shell hydrolysate in clarification of carrot juice and to optimize the enzyme load, pH and time using the Box–Behnken response surface methodology (RSM). The carrot juice was treated with the crude pectinase enzyme (5.60 U mL?1) at different concentrations (0.1–0.5%), pH (4–7), and time (2–6 h). The obtained enzyme was also compared with commercial fungal pectinase at identical conditions. RSM provided optimal clarification conditions of 0.5% (w/v) enzyme load, 7.0 pH, and 6 h of time estimating 100% clarity, whose experimental counterpart was 94.47 ± 0.01%. High values of coefficient of determination (R2 = 0.9631), predicted R2 (0.8989) and insignificant lack‐of‐fit (0.12) also showed that the model was successful in predicting % clarity for various combinations. This study also indicated that crude bacterial pectinase providing about 95% clarity is superior to commercial fungal pectinase, which gave 78% clarity under tested conditions, in terms of clarification ability for carrot juice. 相似文献
74.
Food Science and Biotechnology - In the present study, variety of fruit vinegars were investigated in terms of their physicochemical, microbiological and bioactive properties. Total phenolic and... 相似文献
75.
Deniz Ali Rıza Çaldıran Zakir 《Journal of Materials Science: Materials in Electronics》2022,33(8):5233-5243
Journal of Materials Science: Materials in Electronics - In this study, the Cr/Y3Fe5O12/p-Si/Al heterojunction diode was fabricated with coating the Y3Fe5O12 interface material on p-Si using spin... 相似文献
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In this work, sulfur-doped graphene-coated electrodes are prepared by cyclic voltammetry in different potential ranges and different cycles (from 10 to 50) for selective modification of electrodes by different functional groups. The prepared electrodes are characterized by spectroscopic, microscopic and electrochemical methods. In scanning electron microscopic analysis, formation of graphene layers and their porous structure have been determined. Electrochemical impedance spectroscopic and cyclic voltammetric analyses are also used in electrochemical characterization of the electrodes. Then, the prepared sulfur-doped graphene-coated electrodes by using cyclic voltammetry in one-step and low cost are used as electrode materials of supercapacitor for the first time in the literature. Since the mesoporous structure of the electrodes prepared in lower potential ranges increases, specific capacitance of the electrodes increases from 74 to 1833 mF cm−2 with 10 mA cm−2 current density. This result shows that specific capacitances of prepared electrodes are higher than those of the electrodes prepared with metal-doped in the literature. 相似文献
79.
A. Emre Onuk Murat Akcakaya Jaydeep Bardhan Deniz Erdogmus Dana H. Brooks Lee Makowski 《Journal of Signal Processing Systems》2018,90(2):167-174
Estimation of mixture coefficients of protein conformations in solution find applications in understanding protein behavior. We describe a method for maximum a posteriori (MAP) estimation of the mixture coefficients of ensemble of conformations in a protein mixture solution using measured small angle X-ray scattering (SAXS) intensities. The proposed method builds upon a model for the measurements of crystallographically determined conformations. Assuming that a priori information on the protein mixture is available, and that priori information follows a Dirichlet distribution, we develop a method to estimate the relative abundances with MAP estimator. The Dirichlet distribution depends on concentration parameters which may not be known in practice and thus need to be estimated. To estimate these unknown concentration parameters we developed an expectation-maximization (EM) method. Adenylate kinase (ADK) protein was selected as the test bed due to its known conformations Beckstein et al. (Journal of Molecular Biology, 394(1), 160 1). Known conformations are assumed to form the full vector bases that span the measurement space. In Monte Carlo simulations, mixture coefficient estimation performances of MAP and maximum likelihood (ML) (which assumes a uniform prior on the mixture coefficients) estimators are compared. MAP estimators using known and unknown concentration parameters are also compared in terms of estimation performances. The results show that prior knowledge improves estimation accuracy, but performance is sensitive to perturbations in the Dirichlet distribution’s concentration parameters. Moreover, the estimation method based on EM algorithm shows comparable results to approximately known prior parameters. 相似文献
80.
Electrochemical and optical properties of dicyclohexylmethyl substituted poly(3,4‐propylenedioxythiophene) analogue 下载免费PDF全文
An analogue of disubstituted 3,4‐propylenedioxythiophenes, namely 3,3‐bis(cyclohexylmethyl)‐3,4‐dihydro‐2H‐thieno[3,4‐b][1,4]dioxepin (ProDOT‐CycHex2), was synthesized and its electrochemical polymerization was carried out successfully in an electrolyte solution of 0.1 M tetrabutylammonium hexafluorophosphate dissolved in a mixture of acetonitrile and dichloromethane (3/1: v/v). The corresponding polymer called PProDOT‐CycHex2 has a reduced band gap of 1.85 eV and an electrochromic property: blue/violet when neutralized and highly transparent when oxidized. Also, PProDOT‐CycHex2 film exhibited faster response time (0.7 s) and higher coloration efficiency (769 cm2/C) during oxidation when compared to its benzyl substituted analogue. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46214. 相似文献