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Electron Acceleration by microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： B. F. mOHAmED A.m. gouda Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （Tm） wave propagating inside a rectangular waveguide is analytically studied. The relativistic m.m.ntum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

A Proposed Design, Implementation and Control of Doubly Fed Switched Reluctance motor

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CES Transactions on Electrical machines and Systems 2019年第1期3卷 101-106页

作者： Eid gouda m.Salah H. the Electrical Engineering Department Faculty of EngineeringMansoura University35516Egypt

In this paper,rotor of switched reluctance motor(SRm)is employed by mounting copper windings on the rotor poles as well as the stator *** and stator windings are excited from DC supply in order to increase the developed electro-magnetic torque;thus enhancing the output power of the drive and keeping the system ***,the proposed SRm offers higher reliability than conventional one,if excitation of rotor windings is lost,the drive will turn into a conventional SRm,the drive will continue running as a conventional *** element method magnetics(FEmm)software is applied to obtain the magnetic characteristics of the proposed SRm.A control strategy for excitation of rotor and stator windings is ***/Simulink modeling of the proposed SRm is given and validated by practical *** Results on a prototype show that the proposed SRm is capable of achieving an increased torque compared with conventional SRm drive.

关键词： Doubly Fed SRm SRm Control Wounded Rotor.

DNA Binding and Antitumor Activity of a New Fluores cent ProbeEu(Ⅲ)-Complex Containing 4-methyl-Coumarin moiety

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光谱学与光谱分析 2018年第11期38卷 3611-3621页

作者： Belal H m Hussein mostafa A gouda Omer Sakin Abdulla Faluji mohamed Gomaa Hassan A Azab Walid Fathalla Sherin Arabi Sa wsan mosa Chemistry Department Faculty of Science&ArtsAl UlaTaibah UniversityAl Madina Al MonawarahKSA Department of Chemistry Faculty of ScienceSuez Canal UniversityIsmailiaEgypt Chemistry Department Faculty of ScienceMansoura UniversityAl MansouEgypt Biotechnology Research Center Suez Canal Universitylsmailia 41522Egypt medicinal Chemistry Department Faculty of PharmacySuez Canal Universitylsmailia 41522Egypt Department of mathematical and Physical Sciences Faculty of EngineeringPort-Said UniversityPort-SaidEgypt Department of mathematical and Physical Sciences Faculty of EngineeringSuez Canal UniversitylsmailiaEgypt Department of Chemistry Faculty of Educationel Arish UniversityEgypt

A new europium(Ⅲ)complex containing(4-methyl-2-oxo-2 H-chromen-7-yloxy)-acetic acid moiety(CmmC)was synthesized,characterized,and confirmed as antitumor agent and fluorescent *** spectroscopic measurements of Eu(Ⅲ)in the presence of CmmC were obtained in different *** results show that the strongest Eu(Ⅲ)emission bands were monitored in iso-propyl alcohol while the weakest Eu(Ⅲ)emission band was observed in *** interaction of Eu(Ⅲ)-(CmmC)2 complex with DNA was monitored using absorption and emission *** fluorescence titration measurements,the binding constants of DNA with Eu(Ⅲ)-(CmmC)_2 complex were found to be 1.04×10~5 L·mol^(-1) in Tris-HCl and 1.17×10~7 L·mol^(-1) in DmSO-Tris-HCl buffer(9∶1 V/V).Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Eu(Ⅲ)-complex between the base pair of *** result further confirmed by fluorescent Ethidium bromide displacement *** fluorescence calibration curve was used for the determination of DNA with LOD of 1.2 ng in DmSO-Tris-HCl buffer(9∶1 V/V)and 5 ng in Tris-HCl *** preliminary antitumor investigation shows promising cytotoxicity against mDA-mB-231,mCF-7(m.m.ary cancer),and PC-3(prostate carcinoma)cell lines with IC50 values of 40.63,25.42 and 30.25μmol·L^(-1),respectively.

关键词： Europium (4-methyl-2-oxo-2H-chromen-7-yloxy)-acetic acid DNA sensing Spectroscopic properties Antitumor activ ity

Pitting Corrosion Behaviour of monel-400 Alloy in Chloride Solutions

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Journal of materials Science & Technology 1999年第3期15卷 208-212页

作者： V.K.gouda I.Z.Selim A.A.Khedr and A.m.Fathi(Physical Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) Physical Chemistry Dept. National Research Centre Dokki Cairo Egypt

Pitting corrosion behaviour of monel-400 alloy in 3.5 wt pct NaCl sodium chloride solution has been investigated using the cyclic potentiodynamic anodic polarization technique. The effect of chloride ion concentration, pH values and difFerent temperatures on the pitting parameters were determined. The morphology of the pits produced after anodic polarization treatments was inspected by scanning electron microscope (SEm). The results indicated that, the increase in chloride ion concentration shifts Epit and Eprot of the alloy toward negative values and the pitting potential is much more dependent on pH value in the basic region. The breakdown of passivity with increasing temperature may be due to kinetic changes of passivating films and dissolution rate of the alloy in its passive state

关键词： Figure Pitting Corrosion Behaviour of monel-400 Alloy in Chloride Solutions

Lessons from a methanol poisoning outbreak in Egypt: Six case reports

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World Journal of Critical Care medicine 2020年第3期9卷 54-62页

作者： Ahmed S gouda Amr m Khattab Bruno mégarbane National Egyptian Center of Environmental and Toxicological Research Faculty of MedicineCairo UniversityCairo 11562Egypt Department of Forensic medicine and clinical Toxicology Faculty of MedicineCairo UniversityCairo 11562Egypt Department of medical and Toxicological Critical Care Lariboisière HospitalParis 75010France

BACKGROUND mass methanol poisonings are challenging,especially in regions with no preparedness,management guidelines and available *** SUmmARY Six Ukrainian patients were referred to our emergency department in Cairo,Egypt several hours after drinking an alcoholic beverage made of 70%-ethanol disinfectant bought from a local *** patients presented with severe metabolic acidosis and visual *** were *** was based on the clinical features and chemistry tests due to deficient resources for methanol *** antidote was administered due to fomepizole unavailability and the difficulties expected to obtain ethanol and safely administer it without concentration *** patient died from.m.ltiorgan failure,another developed blindness and the four other patients rapidly *** This methanol poisoning outbreak strongly highlights the lack of safety from hazardous pharmaceuticals sold in pharmacies and limitations due to the lack of diagnostic testing,antidote availability and staff training in countries with limited-resources such as Egypt.

关键词： Hemodialysis Limited resources methanol metabolic acidosis Outbreak Poisoning Case report

Evaluation of Biomarkers in Egyptian Patients with Different Grades of Nonalcoholic Fatty Liver Disease

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Journal of Clinical and Translational Hepatology 2017年第2期5卷 109-118页

作者： Ibrahim H.Borai Yehia Shaker maha moustafa Kamal Wafaa m.Ezzat Esmat Ashour mie Afify Weaam gouda maha m.Elbrashy Biochemistry Department Faculty of Science Ain Shams University Cairo Egypt Biochemistry Department National Research Centre Giza Egypt Department of Internal medicine National Research Center Giza Egypt

Background and Aims:Nonalcoholic fatty liver disease (NAFLD) is a silent disease;its spectrum includes simple steatosis,nonalcoholic steatohepatitis and ***-and anti-inflammatory cytokines play roles in the pathogenesis of NAFLD and insulin resistance (IR).moreover,plasma cell antigen-1 (PC-1) is related to IR and associated with NAFLD ***,we aimed to detect biomarkers,ultrasonographic and anthropometric findings capable of differentiating NAFLD grades,since most previous investigators were concerned more with NAFLD patients without classifying them into ***:A total of 87 NAFLD patients (31 with grade 1 (mild NAFLD),26 with grade 2 (moderate NAFLD) and 30 with grade 3 (severe NAFLD) were included in the study,in addition to 47 controls (grade 0).All subjects underwent ultrasonographic examination for NAFLD *** interleukin-10 (IL-10),plasma interleukin-18 (IL-18) and plasma PC-1 levels were determined using enzyme-linked immunosorbent ***:Homoeostasis model assessment (HOmA)-IR was higher in different NAFLD grades than in *** and anthropometric findings and lipid profile indices (except for high-density lipoprotein cholesterol,which was decreased) were increased with NAFLD *** 3 patients showed significant increase in levels of IL-18 and significant decrease in IL-10 and PC-1 levels when compared to grade 1 ***:Anthropometric and ultrasonographic findings were valuable in differentiating NAFLD *** is very important in NAFLD ***-18,HOmA-index and PC-1 levels could be used to differentiate between NAFLD grades,together with other measurements.

关键词： NAFLD Interleukin-18(IL-18) Interleukin-10(IL-10) Plasma cell antigen-1(PC-1)

Synthesis and Biological Activity of Drug Delivery System Based on Chitosan Nanocapsules

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Advances in Nanoparticles 2014年第4期3卷 148-158页

作者： mohamed gouda Usama Elayaan magdy m. Youssef Department of Chemistry College of Science King Faisal University Hofuf Kingdom of Saudi Arabia Textile Research Division National Research Center Cairo Egypt Department of Chemistry Faculty of Science Mansoura University Mansoura Egypt

Chitosan nanocapsules containing naproxen as an active ingredient were synthesized by ionic gelation method in presence of polyanion tripolyphosphate as a crosslinker. The morphology and diameter of the prepared chitosan nanoparticles was characterized using scanning electron microscopy and transition electron microscopy. Different factors affecting on the size diameter of chitosan nanoparticles such as stirring time and temperature, pH values as well as chitosan concentration were studied. Different factors affecting on the immobilization of naproxen into chitosan nanoparticles such as time, temperature and pH values were optimized. Synthesized naproxen/chitosan nanocapsules were assessed against both Gram positive bacterial strain such as Bacillus subtilis and Staphylococcus aureus and Gram negative bacterial strain such as Pseudomonas aeruginosa and Escherichia coli. Also, the antifungal activity of the naproxen/chitosan nanocapsules against Saccharomyces cerevisiae was demonstrated. Super oxide dismutase like activity of naproxen/chitosan nanocapsules will be determined.

关键词： Chitosan Naproxen Nanocapsules Drug Delivery Systems Antimicrobial Antioxidant DNA Degradation

The Effect of Using Cokriging against Ordinary Kriging When Estimating Phosphate Deposits at Elsebaiya Area, Egypt

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World Journal of Engineering and Technology 2020年第4期8卷 700-711页

作者： H. A. Farag m. A. gouda m. A. Yassin mining and Petroleum Engineering Department Faculty of Engineering Al-Azhar University Cairo Egypt mining Engineering Mining and Petroleum Engineering Department Faculty of Engineering Al-Azhar University Cairo Egypt

Application of geostatistical techniques when evaluating mineral deposits could reflect some geological characteristics which help through the stage of planning and production. In the present study, an attempt has been done on two phosphate deposits at Elsebaiya area on both sides of the River Nile namely: Um Tondoba mine at Elsebaiya East area and Western River Nile mine in Elsebaiya West area. Depending on the available data, statistical analysis illustrated differences in the distribution of P2O5 % and ore thickness within the studied areas. Geostatistics used to start with constructing variograms for P2O5 % and thickness for the two phosphate deposits to be used with ordinary kriging models, also constructing cross variograms between P2O5 % and thickness to be used with cokriging models where the difference in the variogram parameters reflected a specific variation for each deposit horizontally and vertically. The ordinary kriging models and cokriging models illustrated different distribution behavior through both the two kriging techniques.

关键词： Ordinary Kriging Cross Variogram Cokriging Elsebaiya

Computational Aspects of Electromagnetic Fields near H.V. Transmission Lines

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Energy and Power Engineering 2009年第2期1卷 65-71页

作者： Ossama E. gouda Ghada m. AmER Waleed A. SALEm 不详

Biological effects of electromagnetic fields on the human body, animals and plants have been a subject of scientific interest and public concern for their risk on the living organisms such as blood leukemia and others. The high voltage transmission and distribution lines, which pass beside some houses, factories and schools are source of electromagnetic fields. This paper presents the field calculations around and near of high voltage transmission lines 220 kV and 500kV. To calculate the induced current, the power density, the electric field and the magnetic field of grounded and ungrounded human body cylindrical model are used. mATLAB program package is used for mathematical calculation of the distribution of the EmF in human body under high voltage power transmission lines.

关键词： computational aspects EmF H. V. transmission lines