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American Journal of Analytical Chemistry 2019年第1期10卷 38-53页

作者： Ahmad Abu Obaid Motasem Al-Masri Abdalhadi Deghles Nagham taha Shehdeh Jodeh Radi Smail An-Najah National University Nablus Palestine Al-Istiqlal University Jericho Palestine University mohamed Premier Oujda Morocco

The present study is based on the investigation of performance of C,N-bipyrazole receptor grafted onto silica surface (SG2P) of adsorption Arsenic (AS) from aqueous solutions. The effects of operating parameters that include pH, contact time, concentration of As and dosage of adsorbent on adsorption were accomplished. The results clearly showed that the removal efficiency of As was decreased with an increasing of As concentration, pH, and temperature, while it was continuously increasing with time and adsorbent dose. Moreover, the removal efficiency of Cr (VI) adsorption was 75% corresponding to pH;temperature (°C), initial concentration (ppm) and weight of dose (g) were 6, 25, and 0.04 respectively at 24 hours. The adsorption capacity of the synthesized sorbent (SG2P) for arsenic at pH Escherichia coli (ATCC25922) and Staphylococcus aureus (ATCC25932) were as a reference strains, while, the SG2P was able to inhibit growth only at high concentration (MIC = 1.5625 mg/ml).

关键词： Antimicrobial Activity Arsenic Adsorption Pseudo Second Order Escherichia coli

Formation and Characterization of Zinc Phosphate Coating on Reinforcing Steel Rebars

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材料科学与工程（中英文A版） 2013年第7期3卷 481-487页

作者： Mosaad Mohamad Sadawy mohamed taha Nooman Eltohamy Rabie Elsharkawy Mining and Petroleum Engineering Department Faculty of Engineering Al-Azhar University Nasr City 11884 Cairo Egypt Civil Engineering Department Faculty of Engineering Al-Azhar University Nasr City 11884 Cairo Egypt Nuclear & Radiological Regulatory Authority. Cairo Egypt

Zinc phosphate coating has been formed on reinforcing steel rebars by immersion in a zinc phosphate bath to enhance the corrosion resistance. The morphology and the coating composition on the electrode surface were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray diffraction. The phosphate films formed are mainly composed of hopeite (Zn3(PO4)2·4H2O) and phosphophyllite (Zn2Fe(PO4)2·4H2O). A mechanism is proposed to explain the formation of these phases. In addition the corrosion protection of the coating was studied by weight loss and electrochemical measurements. The results showed that, the coating layer on the rebar surface can effectively improve the corrosion resistance of steel in marine environment.

关键词：螺纹钢锌涂层钢筋磷酸 X-射线衍射分析扫描电子显微镜表征耐腐蚀性

污泥好氧堆肥中反硝化作用与腐植酸组分稳定化关系研究

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环境卫生工程 2021年第3期29卷 95-95页

作者：史明子赵昕宇朱龙吉吴俊秋 taha Ahmed mohamed 张旭陈晓蒙赵越魏自民史明子(译) 魏自民(审查) 东北农业大学生命科学学院黑龙江哈尔滨150030 中国环境科学研究院环境标准与风险评估国家重点实验室北京100012 农业研究中心土壤、水与环境研究所埃及吉萨东北农业大学

1研究亮点*反硝化作用的增强降低了好氧污泥堆肥中腐植酸组分含量;*反硝化作用的增强刺激了反硝化功能基因丰度;*反硝化芳香族化合物降解微生物是反硝化功能基因的宿主微生物,是影响腐植酸组分的主要因素。2背景腐植酸是堆肥过程中微生... 详细信息

1研究亮点*反硝化作用的增强降低了好氧污泥堆肥中腐植酸组分含量;*反硝化作用的增强刺激了反硝化功能基因丰度;*反硝化芳香族化合物降解微生物是反硝化功能基因的宿主微生物,是影响腐植酸组分的主要因素。2背景腐植酸是堆肥过程中微生物降解有机物转化形成的一种高分子量芳香族化合物,其形成数量、芳构化程度与堆肥稳定性、腐熟程度及产品品质密切相关。

关键词：污泥好氧堆肥反硝化作用腐植酸芳香族化合物降解微生物反硝化功能基因

Evaluation of the Toxicity of Stone Hair Dye ＆ Paraphenylenediamine by MTT Bioassays in Vitro

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Journal of Chemistry and Chemical Engineering 2010年第5期4卷 36-40页

作者： Hatem Abdel Moniem Ahmed Fathy Fahim Abdul Latif Adel mohamed Kamal El-Dean ragaa mohamed Abdel Maaboud Kamal mohamed EI-Shaieb Eugenio Vilanova Carmen Estevan Assiut Lab.of Medico-legal Department Ministry of JusticeAssuit BranchEgypt Chemistry Department Faculty of ScienceMinia UniversityEI-Minia 61519Egypt Chemistry Department Faculty of ScienceAssiut UniversityAssiut 71516Egypt Department of Forensic Medicine&Toxicology Faculty of MedicineAssiut UniversityAssiut 71516Egypt Institute of Bioengineering Unit of Toxicology and Chemical SafetyUniversity Miguel Hernhndez of Elche(Alicante)Spain

Harmonic Distortion Rate Analysis of H-Bridges Multilevel Inverter

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材料科学与工程（中英文B版） 2011年第3期1卷 308-315页

作者： mohamed Nejib Ben Nasr Khammassi Anis Kebir Faouzi Ben Ammar Unite de recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-1008 Universite de Tunis Tunisia Unite de recherche. LSE INSAT Centre Urbain Nord BP 676 1080 Tunisia

This paper represents comparative study on two control techniques applied to H-bridges multilevel inverter. The considered techniques are standard PWM and harmonic elimination control. Their performances are compared in terms of THD and commutation’s losses so that the choice of power switches is optimized. Simulation results indicated that the harmonic elimination technique exhibits better results than the standard PWM technique, which is sustained by the reduce of the commutation losses, and a power rise for the switches ensuring the use of GTOs, IGCTs.

关键词：多电平逆变器 H桥失真率 PWM技术谐波技术标准电源开关控制技术

Cascaded H-Bridges Asymmetrical 11-Levels Optimization

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材料科学与工程（中英文B版） 2011年第4期1卷 496-503页

作者： mohamed Nejib Ben Nasr Khammassi Anis Kebir Faouzi Ben Ammar Unite de Recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-lO08 Universite de Tunis Tunisia Unitd de Recherche.＂ LSE INSA T Centre Urbain Nord BP 676 1080 Tunis

The following dissertation aims at investigating the multilevel topology basis through the analyses of the harmonic elimination control modeling methodology of the asymmetrical inverter. Thus the contribution of this paper can be summarized mainly by the fact that the pre-calculated PWM control used to control the symmetrical structure, as applied to the asymmetrical structure with a reduced number of cells, provides the same performance level resolution and signal strength to the load terminals, which guarantees a constant voltage frequency report. This observation is similar for the three cells, which allows the use of different drivers such as MOSFET, IGBT and GTO. These results have a good performance from the intrinsic proprieties of each semiconductor for each cell.

关键词：水平分辨率不对称非对称结构优化 H桥级联 MOSFET 消谐控制