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231.
Elsayed Abd El-Rahman Shilkamy Hoda A. El-Shafy Elrouby Mahmoud 《Journal of Solid State Electrochemistry》2021,25(8):2161-2174
Journal of Solid State Electrochemistry - Zinc metal is an important element that can be used for long-life alkaline batteries. In this work, it is found that the addition of minor amounts of... 相似文献
232.
Novel Schiff base ligand based on the condensation of 4,6-diacetyl resorcinol with 2-amino-4-methylthiazole in addition to its metal complexes with Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II) and Cd (II) ions have been synthesized. The structure, electronic properties, and thermal behaviour of Schiff base and its metal complexes have been studied by elemental analysis, mass, 1H NMR, IR spectra, thermal analysis, and theoretically by density function theory. The ligand acted as mononegative bidentate (NO) ligand and all complexes showed octahedral geometry except Cu (II) showed tetrahedral geometry as indicated from the spectral and magnetic studies. The Cu (II), Zn (II) and Cd (II) complexes were non electrolytes while the rest of the complexes were electrolytes. The antibacterial plus anticancer activities of the parent Schiff base and its metal complexes were screened. In addition, the molecular docking study was performed to explore the possible ways for binding to Crystal Structure of Human Astrovirus capsid protein (5ibv) receptor. 相似文献
233.
Aliyari Elnaz Fathi Ali Akbar Alvand Mahrouz Jamshidi Parastoo Shemirani Farzaneh Mozaffari Shahla Neyestani Mahmoud Reza 《Research on Chemical Intermediates》2021,47(5):1905-1918
Research on Chemical Intermediates - This article presents an ultrasound-assisted dispersive magnetic solid-phase extraction method (USA-DMSPE) to preconcentration Cd(II) and Pb(II) simultaneously.... 相似文献
234.
235.
Nafiseh Mansouriieh Mahmoud Reza Sohrabi Morteza Khosravi 《Arabian Journal of Chemistry》2019,12(8):2524-2532
This study synthesized bimetallic Fe/Ni nanoparticles and used them for catalytic degradation of profenofos, an organophosphorus pesticide. This novel bimetallic catalyst (Fe/Ni) was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray analysis spectroscopy (EDAX) and X-ray diffraction (XRD). The bimetallic nano-catalyst was prepared at diameters of 20–50 nm and was shown to effectively degrade profenofos. A three-factor central composite design combined with response surface methodology was used to maximize profenofos removal using the bimetallic system. A quadratic model was built to predict degradation efficiency. ANOVA was used to determine the significance of the variables and interactions between them. Good correlation between the experimental and predicted values was confirmed by the high F-value (16.38), very low P-value (<0.0001), non-significant lack of fit, an appropriate coefficient of determination (R2 = 0.936) and adequate precision (14.75). The highest removal rate attained was 94.51%. 相似文献
236.
Mustafa A. S. Gouda Mounir A. I. Salem Naglaa F. H. Mahmoud 《Journal of heterocyclic chemistry》2020,57(11):3988-4006
Some poly functionalized heterocyclic-compounds containing pyridine-moieties were readily assembled by combining differently functionalized pyridopyrimidine-6-carbonitrile derivatives 1a,b with different electrophilic and nucleophilic reagents via short synthetic routes. The structures of the prepared derivatives were ascertained from their-spectral-and elemental analyses. Some of the synthesized compounds were tested as plausible antitumor agents. Most of those tested compounds likes 7 , 9 , 10 , 11a showed cytotoxic potencies against different tumor cell lines. In addition, the assessments for their antioxidant activities have also been done and compound 9 exhibited the highest antioxidant activity while compounds 7 and 10 showed moderate activities. Finally, molecular docking studies were carried out which favorably indicated a high support for the experimental-results. 相似文献
237.
Shariq Ali Norah Albekairi Xiao-Ming Wang Svetlana Patrikeeva Tatiana N. Nanovskaya Mahmoud S. Ahmed 《液相色谱法及相关技术杂志》2018,41(5):232-238
Ex vivo placental perfusion experiments are important in understanding the quantity and mechanisms of xenobiotic transport to the fetus during pregnancy. Our study demonstrates that paclitaxel and antipyrine concentrations in placental perfusion medium containing physiological concentrations of human serum albumin during pregnancy (30?mg/mL) can be quantified by RP-HPLC and UV detection. A liquid-liquid extraction method was developed for the quantification of paclitaxel and celecoxib (internal standard) from perfusion medium. Antipyrine, which is a necessary marker in placental perfusions for determining the validity of experiments and calculating the clearance index of xenobiotics, was also analyzed by HPLC and UV detection. Antipyrine concentrations were determined by HPLC after precipitating the perfusion medium in acetonitrile and separating the precipitated proteins by centrifugation. Concentrations were fitted to linear regressions with R2 values approaching 1. Lower limits of detection for paclitaxel and antipyrine were 100?ng/mL and 200?ng/mL, respectively. Both methods demonstrated high intra-day and inter-day precision and trueness. Additionally, the use of these methods was demonstrated in a placental perfusion experiment using Taxol® (paclitaxel dissolved in Cremophor-EL). The fetal transfer rate of Taxol was 6.6% after 1 hour. 相似文献
238.
Mahdi Ghorbani Mahmoud Chamsaz Gholam Hossein Rounaghi 《Analytical and bioanalytical chemistry》2016,408(16):4247-4256
239.
In this work, low‐moisture glycidyl azide polymer (GAP) was successfully prepared using a modified two‐step method. The modified method resembles the structure of the classical two‐step method, which is widely used to prepare the GAP. Firstly, epichlorohydrin (ECH) is polymerized into polyepicholorohydrin (PECH), which is subjected afterward to azidation step using sodium azide (NaN3). Interestingly, minimizing the water content in the final GAP product, which is a challenging when dealing with GAP as a rocket propellant binder, was effectively achieved by utilizing low boiling point solvents instead of the relatively high boiling point Dimethyl formamide (DMF), monitoring the volatility of ECH and controlling the exothermicity of the reaction. Prepared GAP samples were investigated using Fourier transformer infra‐red (FT‐IR), gel‐permeation chromatography (GPC) and elemental analysis apparatus (CHNS) were used to characterize the product. The moisture % in the final product was examined using the Karl‐Fisher Technique. Results showed the successful preparation of GAP with low water content (<0.01 %), high average molecular weight (> 2000 g · mol–1), 42.82 % nitrogen, a viscosity of 3484 cP at 20 °C, yield ranges between 95–98 % and a polydispersity index of 1.2. The prepared GAP is promising for replacement of the classical GAPs in the energetic materials applications. 相似文献
240.
Amira Mahmoud Mosaab Echabaane Karim Omri Julien Boudon Lucien Saviot Nadine Millot Rafik Ben Chaabane 《Molecules (Basel, Switzerland)》2021,26(4)
Copper-doped zinc oxide nanoparticles (NPs) CuxZn1−xO (x = 0, 0.01, 0.02, 0.03, and 0.04) were synthesized via a sol-gel process and used as an active electrode material to fabricate a non-enzymatic electrochemical sensor for the detection of glucose. Their structure, composition, and chemical properties were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) and Raman spectroscopies, and zeta potential measurements. The electrochemical characterization of the sensors was studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). Cu doping was shown to improve the electrocatalytic activity for the oxidation of glucose, which resulted from the accelerated electron transfer and greatly improved electrochemical conductivity. The experimental conditions for the detection of glucose were optimized: a linear dependence between the glucose concentration and current intensity was established in the range from 1 nM to 100 μM with a limit of detection of 0.7 nM. The proposed sensor exhibited high selectivity for glucose in the presence of various interfering species. The developed sensor was also successfully tested for the detection of glucose in human serum samples. 相似文献