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排序方式: 共有191条查询结果,搜索用时 31 毫秒
1.
Caillau Jean-Baptiste Djema Walid Gouzé Jean-Luc Maslovskaya Sofya Pomet Jean-Baptiste 《Journal of Optimization Theory and Applications》2022,194(2):375-407
Journal of Optimization Theory and Applications - We consider the problem of maximization of metabolite production in bacterial cells formulated as a dynamical optimal control problem (DOCP).... 相似文献
2.
Walid Mabrouk Ridha Lafi Jean Franois Fauvarque Amor Hafiane Cyrille Sollogoub 《先进技术聚合物》2021,32(1):304-314
The purpose of this work is to study the desalination of brackish water using a new ion exchange membrane, made from sulfochlorated polyethersulfone (Cl‐PES), and crosslinked using aminated polyethersulfone (NH2‐PES) as a crosslinking reagent. This membrane, named ClNH2 membrane, has been obtained by reaction between Cl‐PES with 1.3 SO2Cl groups per monomer unit and 0.2 equivalent amount of NH2‐PES. ClNH2 membrane has been characterized in terms of contact angle, transport number, intrinsic conductivity, and water uptake (as a function of temperature). Electrodialysis performances of the newly synthetized membranes have been measured using an electrodialysis cell at a laboratory scale and compared to commercial membranes. All the experiments have been performed using synthetic brackish water solutions prepared from sodium chloride salts with different concentrations (varying from 0.5 to 5.0 g/L). The concentration of different water samples obtained has been found to be below the amount recommended by the World Health Organization (WHO) for drinking water. 相似文献
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W. A. Farooq S. M. Ali Walid Tawfik Amanullah Fatehmulla M. Aslam A. S. Al-Dwayyan M. S. AlSalhi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(13):2446-2450
ZnO Nano powders were prepared by co-precipitation method which includes post-oxidation and annealing in air. Influence of laser irradiation was carried out using 355 nm laser on the physical properties of ZnO nanoparticles. SEM studies reveal agglomeration of grains resulting into enlargement and deformation of the nanoparticles. XRD pattern exhibited decrease in FWHM which is a clear evidence of the increase in crystallite size due to laser irradiation. Optical properties showed decrease in the band gap of the laser irradiated Nano powders. The observed results indicated the UV laser irradiation increases the ZnO nanoparticles crystallinity that affects the optical properties of the ZnO. 相似文献
5.
Synthesis,spectroscopic characterization,thermal behaviour,in vitro antimicrobial and anticancer activities of novel ruthenium tricarbonyl complexes containing monodentate V‐shaped Schiff bases 下载免费PDF全文
The interaction of Ru3(CO)12 with a novel family of monodentate V‐shaped Schiff base ligands (L1–4; L1: (E)‐1‐(4‐((4‐bromobenzylidene)amino)phenyl)ethanone, L2: (E)‐1‐(3‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L3: (E)‐1‐(4‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L4: (E)‐1‐(3‐(3,4‐dimethoxybenzylideneamino)phenyl)ethanone) in air under atmospheric pressure afforded the novel complexes [Ru(CO)3(L1–4)2]. The parent ligands and their complexes were characterized using elemental analyses and spectroscopic techniques. In addition, the structure of the representative ligand L1 was determined using single‐crystal X‐ray analysis. The stereochemistry and theoretical optimization of the three‐dimensional geometry of the ligands and their complexes were justified. In vitro antimicrobial screening against bacterial stains Escherichia coli and Staphylococcus aureus and fungus Candida albicans was conducted. Cytotoxicity of the compounds as anti‐tumour agents was evaluated against liver carcinoma (HepG2), breast carcinoma (MCF7) and colon carcinoma (HCT‐116) cell lines relative to cisplatin and doxorubicin. The complexes showed variable in vitro cytotoxic activities against the three studied cell lines, with IC50 values less than those of cis‐platin, and thus appear to be building blocks for promising anti‐tumour agents. 相似文献
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Youssef Walid Mohamed El Sheikh Ahmed Said Ahmed Sherien Hussien Morsy Ahmed Morsy Ahmed 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):87-96
Journal of Radioanalytical and Nuclear Chemistry - Polyacrylic acid/polyaniline composite (a three-dimensional cross-linked hydrophilic chelating polymeric sorbent) was improved for promoted... 相似文献
8.
Mohamed M. Ibrahim Gaber A.M. Mersal Nagi El-Shafai Mohamed M. Youssef Hanaa Shokry 《Comptes Rendus Chimie》2014,17(10):1013-1022
A dithiolate-containing a carbamate mononuclear cobalt(II) complex namely, [Co(Boc-S)2] (1), was obtained by the reaction of a methanolic solution of cobalt(II) nitrate hexahydrate with two equimolar amounts of the deprotonated form of tert-butyl N-(2-mercaptoethyl)carbamate (Boc-SH). The cobalt(II) complex (1) was characterized in the solid state and in solution by using FT–IR, Raman, UV–visible, and EI–mass spectroscopies, as well as thermal and X-ray diffraction studies. Spectral data showed that the carbamate (Boc-SH) acts as a mono-anionic bidentate ligand coordinating the cobalt(II) ion through two imine nitrogen and two deprotonated thiolate sulfur donor atoms in a distorted tetrahedral geometry. The thermoanalytical data evidence that the complex is stable up to 165 °C and undergoes complete decomposition, resulting in CoO. TEM imaging of the oxide residue shows its nano size clusters, suggesting that the complex (1) may be used as a precursor for nano-oxides. X-ray powder diffraction patterns evidence an isomorphism among the complex. The redox behavior of the cobalt(II) complex was also investigated by cyclic voltammetry. The reaction of the dithiolate cobalt(II) complex (1) with methyl iodide appears to occur intramolecularly with the cobalt-bound dithiolate, forming the cobalt(II)-bound dithioether complex [Co(Boc–SCH3)2]I2 (2), as a dication complex with a clean second-order reaction of 13.24 × 10−2 M−1·s−1. 相似文献
9.
Ramzia I. El-Bagary Gabor Patonay Asmaa A. Elzahr Ehab F. Elkady Walid A. Ebeid 《Chromatographia》2014,77(3-4):257-264
A rapid and precise LC method was developed for the simultaneous determination of aliskiren hemifumarate (ALS), amlodipine besylate (AML) and hydrochlorothiazide (HCZ) using acetonitrile:25 mM octane sulfonic acid sodium salt monohydrate in water (60:40 v/v) as the mobile phase. The flow rate was maintained at 1.2 mL min?1 on a stationary phase composed of Supelco, Discovery® HS (C18) column (25 cm × 4.6 mm, 5 μm). Isocratic elution was applied throughout the analysis. Detection was carried out at λ max (232 nm) at ambient temperature. The method was validated according to ICH guidelines. Linearity, accuracy and precision were satisfactory over the concentration ranges of 32–320, 2–44 and 4–64 μg mL?1 for ALS, AML and HCZ, respectively. LOD and LOQ were estimated and found to be 0.855 and 2.951 μg mL?1, respectively, for ALS, 0.061 and 0.202 μg mL?1, respectively, for AML as well as 0.052 and 0.174 μg mL?1, respectively, for HCZ. The method was successfully applied for the determination of the three drugs in their co-formulated tablets. The results were compared statistically with reference methods and no significant difference was found. The developed method is specific and accurate for the quality control and routine analysis of the cited drugs in pharmaceutical preparations. 相似文献
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