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Advances in Materials Physics and Chemistry 2014年第5期4卷 93-104页

作者： Chewki Zegadi Khalil Abdelkebir Denis Chaumont mohamed Adnane saad Hamzaoui Laboratory of Electron Microscopy and Materials Sciences University of Science and Technology of Oran El-Mnaouer Oran Algeria Nanoform—ICB Université de Bourgogne Dijon France

In this work, Undoped Zinc Oxide (ZnO) and Sndoped Zinc Oxide (ZnO:Sn) films have been deposited by sol-gel dip coating method, where the Sn/Zn atomic ratio was 3% and 5% in the solution. The effects of Sn incorporation on morphological, structural and optical properties of ZnO films were investigated. The Scanning Electron Microscopy (SEM) showed that the morphological surface of the films was affected by Sn low doping. The X-Ray Diffraction (XRD) patterns showed that all films have polycrystalline structures, and the doping incorporation has not lead to substantial changes in the structural characteristics of ZnO films. The crystallite size was calculated using the well-known Scherrer’s formula and found to be in the range of 23 - 40 nm. The measurements from UV-Visible Spectrophotometer (U-Vis) indicated that the highest average optical transmittance in the visible region was related to Undoped ZnO film, then the optical band gap and Urbach energy values of thin films were calculated. The X-Ray Photoelectron Spectroscopy (XPS) has demonstrated that Sn is incorporated in ZnO lattice.

关键词： Sol-Gel Dip-Coating ZnO Films Sn Low Doping SEM Micrographs X-Rays Patterns Optical Properties XPS Spectrum

Determination of Photon and Elementary Particles Rest Masses Using Maxwell’s Equations and Generalized Potential Dependent Special Relativity

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Natural Science 2020年第8期12卷 588-598页

作者： Abeer Mohammed Khairy Ahmed Mashair Ahmed Mohammed Yousif Zainab Mustapha Kurawa Zoalnoon Ahmed Abeid Allah saad Suhair Salih Makawy Mohammed Idriss Mohammed Mubarak Dirar Abd-Alla Sami abdalla Elbadawi mohamed Departmentof Physics Faculty of Art and Science at AL Muznab AL Qassim University AL Muznab Kingdom of Saudi Arabia Department of Physics Faculty of Science and Education at Alkhurma Taif University Alkhurma Kingdom of Saudi Arabia Department of Physics School of Science Education Saadatu Rimi College of Education Kumbosto Kano Nigeria Departmentof Physics Faculty of Arts and Sciences Dhahran Aljanoub King Khalid University Dahran Kingdom of Saudi Arabia Department of Physics Faculty of Science Taif University Taif Kingdom of Saudi Arabia Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan Department of Physics Faculty of Education Gadarif University Gadarif Sudan

The nature and origin of the photon and elementary rest masses are some of the challeng-ing problems that physics face. The approaches used to solve these problems are complex and time-consuming. Specifically, the photon rest mass pays attention to theoretical physi-cists. Many experimental works show that the photon rest mass is non zero. This problem can be solved using generalized potential dependent special relativity, which has been de-rived using simple arguments, and Maxwell’s equations, besides the conventional Einstein energy-momentum relation. The results obtained show that the rest mass of photons and elementary particles are strongly dependent on the vacuum energy and a universal con-stant. This result conforms with the models that predict time decaying vacuum energy as-sociated with production of smaller rest mass particles followed by larger masses. The two potential dependent mass expressions conform with the cosmological models that suggest the photon is generated first by assuming the universe consisting of total constant vacuum with decaying cosmological part and mass generating part. Using Maxwell’s equations, beside plank and De Broglie hypothesis together with special relativity energy-momentum relation the photon rest mass is estimated. It was shown that the photon rest mass is ex-tremely small compared to the electron mass.

关键词： Photon Elementary Particles Maxwell’s Equations Potential Dependent Special Relativity Vacuum Energy

Correlation of Magnetoresistance and Thermoelectric Power in La1-xLixMnOy Compounds

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Journal of Electromagnetic Analysis and Applications 2011年第1期3卷 27-32页

作者： Ahmed mohamed Ahmed Abed El Rahman Ahmed saad Mahrous Rashad Ahmed 不详

The temperature dependences of the thermoelectric power, TEP, (S) and magnetoresistance (MR) effect of La1-xLixMnOy (x = 0.05, 0.1, 0.15, 0.2 & 0.25 at %) fixed valence doped compounds were studied between 80K and 320K. X-ray powder diffraction (XRD) showed that the samples are single phase. We found the correlation of structures to the mag-netoresistance (MR) and the thermoelectric power (S) which we assigned to change the specific branches of the magnon /phonon spectra with x. We also observed a splitting of the Curie and the metal insulating temperature TC > Tms.

关键词： Thermoelectric Power Magnetoresistance the Curie Temperature

The Impact of Pretransplant Disease Characteristics on the Outcome of Autologous Stem Cell Transplantation for Neuroblastoma with High-Risk Features: A Retrospective Model from a Limited Resources Country

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Journal of Cancer Therapy 2019年第6期10卷 422-432页

作者： Ahmed Elhemaly Mahmoud Hammad mohamed saad Zaghloul Maged Elshafie Naglaa Elkinaae mohamed Khaled Alaa El-Haddad Department of Pediatric Oncology National Cancer InstituteCairo UniversityCairoEgypt Department of Pediatric Oncology Children’s Cancer Hospital EgyptCairoEgypt Department of Radiation Oncology National Cancer InstituteCairo UniversityCairoEgypt Department of Radiation Oncology Children’s Cancer Hospital EgyptCairo UniversityCairoEgypt Department of Surgical Oncology National Cancer InstituteCairo UniversityCairoEgypt Department of Surgical Oncology Children’s Cancer Hospital EgyptCairoEgypt Department of Pathology National Cancer InstituteCairo UniversityCairoEgypt Department of Pathology Children’s Cancer Hospital EgyptCairoEgypt Department of Research Children’s Cancer Hospital EgyptCairoEgypt

High-risk neuroblastoma still has poor survival outcome. Improvement of outcome is attributed to the consolidation of chemotherapy by autologous bone marrow transplant. Further improvement of the outcome by tandem autologous transplant is followed by immune therapy. We aimed with this study to correlate initial disease characteristics with the outcome of transplanted high-risk neuroblastoma. A retrospective analysis was done for 73 transplanted patients. Patients were treated in Children’s Cancer Hospital Egypt from July 2012 to July 2015. Seventy patients received Busulphan/Melphalan conditioning. The 3-year overall survival (OS) and event-free survival (EFS) was 63.3% and 51.3%, respectively. Disease stage did not impact the OS and EFS, P = 0.54 and 0.62 respectively. Status of MYCN did not reflect statistically on outcome for tumors with amplified compared to nonamplified (EFS, 49% and 63.1%, respectively). Response after induction chemotherapy pointed that patients who had objective response (complete response, very good partial response and partial response) were better compared to those with less response with EFS and OS of 53.3% and 64.2% compared to 49.3% and 63.5%, respectively, which may indicate that chemo-sensitive tumors have better outcome. By the end of the study, twenty-seven patients relapsed, out of them 25 patients died. Pretransplant risk features for neuroblastoma was nullified by autologous stem cell transplant. The modest outcome observed, highlights some limitations that need to be sorted out in countries with limited resources. The introduction of immune therapy and tandem transplant is needed to achieve a better outcome, yet it adds to more financial burden.

关键词： Neuroblastoma Limited-Resource Autologous Bone Marrow Transplant Busulphan Melphalan

Assessment on Excavatability in Weathered Sedimentary Rock Mass Using Seismic Velocity Method

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材料科学与工程（中英文A版） 2011年第2X期1卷 258-263页

作者： Mohamad Edy Tonnizam saad Rosli Md Noor Muhazian Md Isa mohamed Fauzi Department of Geotechnics and Transportation Faculty of Civil Engineering Universiti Teknologi Malaysia 81310 UTM Skudai.Johor Malaysia Universiti Sains Malaysia Penang Malaysia

Seismic refraction method is one of the most popular methods in assessing surface excavation. The main objective of the seismic data acquisition is to delineate the subsurface into velocity profiles as different velocity can be correlated to identify different materials. The physical principal used for the determination of excavatability is that seismic waves travel faster through denser material as compared to less consolidated material. In general, a lower velocity indicates material that is soft and a higher velocity indicates more difficult to be excavated. However, a few researchers have noted that seismic velocity method alone does not correlate well with the excavatability of the material. In this study, a seismic velocity method was used in Nusajaya, Johor to assess the accuracy of this seismic velocity method with excavatability of the weathered sedimentary rock mass. A direct ripping run by monitoring the actual production of ripping has been employed at later stage and compared to the ripper manufacturer’s recommendation. This paper presents the findings of the seismic velocity tests in weathered sedimentary area. The reliability of using this method with the actual rippability trials is also presented.

关键词：地震折射法岩体风化质量评估速度法沉积岩地震波速度地震数据采集合材料

Experimental Study of Heat Transfer to Flowing Air inside a Circular Tube with Longitudinal Continuous and Interrupted Fins

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Journal of Electronics Cooling and Thermal Control 2012年第1期2卷 1-16页

作者： saad A. El-Sayed Sayed A. EL-Sayed mohamed M. saadoun Department of Mechanical Power Engineering Zagazig University El-Sharkia Egypt

Experimental investigations have been performed to determine the detailed module-by-module pressure drop and heat transfer coefficient of turbulent flow inside a circular finned tube. The tubes are provided with longitudinal fins continuous or interrupted in the stream wise direction by arranging them both in a staggered and in-line manner. Experiments are carried out for two different fin geometries, with two numbers of fins (N = 6 and 12). All tested finned tubes have 16 modules each with length equal to the tube diameter (L = D = 30 mm). The thermal boundary condition considered here, is a uniform heat flux. The module-by-module heat transfer coefficient is found to vary only in the first modules, and then attained a constant thermally periodic fully developed value after eight to twelve modules. The results also showed that in the periodic hydrodynamic fully developed region, the value of the pressure drop along the tube with continuous fins is greater than that of the in-line arrangement, and lower than that of the staggered arrangement. Furthermore, the results showed that in the periodic fully developed region, the tube with continuous fins produces a greater value of the heat transfer coefficients than that the tube with interrupted fins, especially through a high range of Reynolds number (5 × 104 > Re > 2 × 104). The tube with Staggered arrangement of fins produces a greater value of the heat transfer coefficient than the tube with continuous fins and the in-line arrangement finned tube at low Reynolds number (Re < 1.2 × 104).). It was found that the fins efficiency is greater than 90 percent;in the worst case (maximum Reynolds number with continuous fins tube).

关键词： Internal Flow Turbulent Flow Heat Transfer Interrupted and Continuous Fins Fin Analysis

Impact of Gender Difference on Characteristics and Outcome of Chronic Hepatitis C

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Open Journal of Gastroenterology 2020年第11期10卷 281-294页

作者： Mahmoud Saif-Al-Islam Hamdy saad mohamed Mustafa Adel Younis Mahmoud Yosef Abdelhamid Magda mohamed Ali Safaa Khalaf Departments of Tropical Medicine and Gastroenterology Sohag University Hospital Sohag Egypt Departments of Internal Medicine Sohag University Hospital Sohag Egypt Departments of Clinical Pathology Sohag University Hospital Sohag Egypt Departments of Radiology Sohag University Hospital Sohag Egypt Departments of Community Medicine Sohag University Hospital Sohag Egypt

Gender difference in chronic hepatitis C (CHC) infection is not previously well studied. We aimed to analyze the effect of gender difference on the risk factors of CHC, disease progression, and outcome after oral direct acting antiviral (DAA) therapy. The study was conducted at Tropical Medicine and Gastroenterology Department, Sohag University, Egypt, in the period between 2018 and 2020. 775 patients were evaluated for hepatitis C virus (HCV) risk factors. Laboratory investigations, abdominal ultrasound and liver Shear wave elastography (SWE) were done. The patients were given antiviral therapy and followed up to assess the response and side effects of DAA therapy. 434 (56%) of study patients were males and 341 (44%) were females. Catching infection from blood transfusion and intravenous (IV) injection of tarter emetic was significantly higher in males, while catching infection from surgical operation was significantly higher in females. Hepatic fibrosis was significantly more extensive in males. Side effects were reported more in females. Sustained virological response (SVR) 12 was reported in 98.6%. Females had a slightly better SVR12 than males (99.4% versus 97.9%). In conclusion males were different from females in exposure to HCV risk factors. After introduction of blood screening and

关键词： Chronic HCV Risk Factors Gender Difference DAA Therapy

Corrosion Resistance of API5L X52 Carbon Steel in Sulfide Polluted Environments

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Materials Sciences and Applications 2016年第1期7卷 39-50页

作者： Randa Abdel-Karim mohamed Ali Farag Hafiz Abdel-Azim Ahmed saad El-Raghy Department of Metallurgy Faculty of Engineering Cairo University Giza Egypt

In the present work, the corrosion behavior of base and welded API5L X-52 carbon steel coupons in synthetic ground water solution NS-4 was studied. Subsequently, the morphology and composition of the corrosion product deposits were determined using scanning electron microscopy (SEM). Based on weight loss as well as Tafel’s measurements, increasing the sulfide ions content above 0.4 mM, had an inhibition effect on the corrosion behavior of carbon steel. According to EDAX analyses, increasing of sulfide concentration from 0.4 to 4 mM Na2S, the Fe/S ratio decreased from 12.02 at 0.4 mM to 2.6 at 4 mM Na2S.

关键词： Carbon Steel Sulfides Weight Loss Anodic Dissolution Polarization

Impact of Pre-Radiotherapy and/or Chemoradiotherapy Hemoglobin Level on Response to Treatment in Laryngeal and Hypophayrngeal Squamous Cell Carcinoma

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Journal of Cancer Therapy 2018年第4期9卷 362-381页

作者： Dina Ragab Diab Ibrahim mohamed saad Hasaballah Marwa mohamed El-Begermy Ahmed Abdel Aziz Ahmed Soha Ahmed Abuelela Clinical Oncology Department Faculty of Medicine Ain-Shams University Cairo Egypt Ear Nose Throat ENT Department Faculty of Medicine Ain-Shams University Cairo Egypt Clinical Pathology Department Ain-Shams University Cairo Egypt

Background: Anemia is reported by many studies as an important risk factor for poor locoregional disease control and survival in head and neck carcinoma. We aimed to study the frequency and prognostic effect of low hemoglobin (Hb) level in head and neck squamous cell carcinoma (HNSCC) before radiotherapy (RT) and/or chemoradiotherapy (CRT). Material and Methods: We retrospectively studied the charts of 86 patients diagnosed with laryngeal and hypopharyngeal SCC in a university hospital in Cairo, Egypt. Based on the World Health Organization (WHO), anemia was diagnosed in males at Hb levels 13 g/dl in 44/75 (58.7%). Tumor sites were larynx in 77 (89.5%) and hypopharynx in 9 (10.5%) patients. Disease stage 3, 4 was common in 59/86 (68.6%) patients. Thirty-six (41.8%) patients had surgery. 13/86 (15.1%) patients received induction chemotherapy, while 31/86 (36.0%) had concomitant chemoradiotherapy. Radiotherapy was given in 65/86 (75.58%) patients. The mean RT dose was 66 Gy. Non-anemic patients had significant higher inci-dence of complete response (CR) to treatment (p = 0.034). 25.8% of male pa-tients with Hb 13 g/dl (p = 0.403). Female patients whether anemic or non-anemic had no recurrence (p = 0.036 and p = 0.403 respectively). The median duration of DFS and OS was 6.52 and 9.33 months respectively. Pretreatment Hb level had statistical significant effect on respons

关键词： Hemoglobin Radiotherapy Chemotherapy Tumor Hypoxia Local Control Survival

Microbiologically influenced corrosion of 304L stainless steel caused by an alga associated bacterium Halomonas titanicae

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Journal of Materials Science & Technology 2020年第2期37卷 200-206页

作者： Yuqiao Dong Yassir Lekbach Zhong Li Dake Xu Soumya El Abed saad Ibnsouda Koraichi Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China Center for Marine Materials Corrosion and Protection College of MaterialsXiamen UniversityXiamen 361005China Laboratory of Microbial Biotechnology Faculty of Science and TechnologySidi Mohamed Ben Abdellah UniversityB.P.2202FezMorocco

Algae are reported to be corrosive,while little is known about the role of the algae associated bacteria in the corrosion *** the present study,Halomonas titanicae was isolated from a culture of an alga strain,Spirulina platensis,and identified through 16 S rRNA gene *** behavior of 304L stainless steel(SS)coupons in the presence and absence of *** was characterized by using electrochemical measurements and surface *** results showed that *** significantly accelerated the corrosion rate and decreased the pitting potential of 304L SS in the biotic *** removal of the corrosion products and biofilms,severe pitting corrosion caused by *** was *** largest pit depth after 14 d reached 6.6μm,which was 5.5 times higher than that of the sterile control(1.2μm).This is the first report revealing that an alga associated bacterium can induce microbiologically influenced corrosion(MIC),and a further concern is raised that whether algae play a role in the MIC process.

关键词： Microbiologically influenced corrosion Halomonas titanicae Pitting corrosion