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modelling and Optimal Design of Hybrid Power System Photovoltaic/Solid Oxide Fuel Cell for a mediterranean City

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Energy Engineering 2021年第6期118卷 1767-1781页

作者： Bachir melzi Nesrine Kefif mamdouh el Haj Assad Haleh Delnava Abdulkadir hamid School of materials Sciences and Engineering Wuhan University of TechnologyWuhanChina Power and Control Department Electronic and Electrical Engineering InstituteM’hamed Bougara UniversityBoumerdesAlgeria Sustainable and Renewable Energy Engineering Department University of SharjahSharjahUnited Arab Emirates Institute of manufacturing Information and Systems National Cheng Kung UniversityTainanTaiwan electrical Engineering Department University of SharjahSharjahUnited Arab Emirates

This work presents a hybrid power system consisting of photovoltaic and solid oxide fuel cell(PV-SOFC)for electricity production and hydrogen *** simulation of this hybrid system is adjusted for Bou-Zedjar city in north *** software was used for this simulation to calculate the power output and the total net present *** method used depends on the annual average monthly values of clearness index and radiation for which the energy contributions are determined for each component of PV/SOFC hybrid *** economic study is more important criterion in the proposed hybrid system,and the results show that the cost is very suitable for the use of this hybrid system,which ensures that the area is fed continuously with the sufficient energy for the load which assumed to be 500 kW in the peak *** optimized results of the present study show that the photovoltaic is capable of generating 8733 kW electricity while the SOFC produces 500 kW *** electrolyzer is capable of producing 238750 kg of hydrogen which is used as fuel in the SOFC to compensate the energy lack in nights and during peak season.

关键词： Energy storage PV/SOFC hybrid systems hydrogen production energy and economic optimization

Geochemistry of lamprophyres associated with uranium mineralization, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2007年第4期26卷 356-365页

作者： mohamed E. Ibrahim mohamed m. el-Tokhi Gehad m. Saleh mamdouh A. Hassan mohamed A. Rashed Nuclear materials Authority P. O. Box 530 El Maadi Cairo Egypt Geology Deprtment Faculty of Science United Arab Emirates University United Arab Emirates

Two brecciated shear zones (NNW-SSE) are found crosscutting cataclastic rocks. The cataclastic rocks (3.0 km2) occupy the core of the granitic pluton and enclose a roof pendant of mafic-ultramafic rocks. The NNW-SSE-extending lamprophyre dykes vary in thickness from 0.5 m to 1 m and up to 800 m long, cutting the cataclastic rocks and are composed mainly of plagioclases, amphiboles, relics of pyroxenes and K-feldspar phenocrysts embedded in fine-grained groundmass. They are characterized as being peraluminous, calc-alkaline in composition (chemical trap) and enriched in calcite, sulfide and P2O5. The lamprophyres were affected by hydrothermal alteration (chlorite-carbonate alteration) while the cataclastic rocks were affected by diagenetic alteration (K-feldspar-albite alteration). Uranium mineralization is the product of hydrothermal events and has been investigated by X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEm), involving primary uranium minerals (U3O8) and secondary uranium minerals (uranophane and beta-uranophane, kasolite, torbernite, autonite and meta-autonite) in addition to U- bearing minerals (astrocyanite, betafite and fergusonite). The presence of different mineral parageneses associated with clay minerals indicates that the lamprophyres were subjected to acidic and alkaline mineralizing solutions. moreover, the U-Zr/U, U-Ce/U values show negative correlations, confirming U-enrichment in both cataclastic rocks and shear zones while the Th-eU/eTh, Th-Zr/Th and Th-Ce/Th values show negative correlations, indicating that the U-bearing solutions are rich in Th in the cataclastic rocks only.

关键词：碎裂岩石剪切区域煌斑岩热液蚀变埃及西南地区沙漠地带

measuring Impact of Lean manufacturing Tools for Continuous Improvement on Economic Sustainability

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 452-474页

作者： Luis Javier márquez Figueroa Jorge Luis García-Alcaraz Ahmed I.Osman Alfonso Jesús Gil López Yashar Aryanfar mika Sillanpää mamdouh el Haj Assad Department of electrical Engineering and Computer Science Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico Department of Industrial Engineering and manufacturing Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico School of Chemistry and Chemical Engineering Queens UniversityBelfastNorthern IrelandUK Department of Economic and managerial Sciences University of La RiojaLa RiojaSpain Department of Chemical Engineering University of JohannesburgJohannesburgSouth Africa Department of Sustainable and Renewable Energy Engineering University of SharjahSharjahUAE

Using Lean manufacturing(Lm)tools in production processes is crucial for companies’economic,environmental,and social sustainability *** study shows a structural equation model(SEm)that shows the relationship between Lm Tools like Kaizen(KAI),Gemba(GEm),Value Stream mapping(VSm)and Key Performance Indicator(KPI)with Economic Sustainability(ECS).Seven hypotheses were evaluated with data from 179 responses to a questionnaire about the mexican maquiladora industry,showing that these variables are *** a 95%confidence level,the model was evaluated using the partial least squares *** findings indicate that the relationships between KAI and GEm and KAI and VSm have the strongest relationship,followed by VSm and ECS;however,VSm has the strongest effect on *** on these findings,it is recommended that managers adopt a continuous improvement(KAI)approach based on working directly on the shop floor(GEm and VSm)to support their decisions regarding economic growth(ECS).

关键词： Lean manufacturing economic sustainability structural equation model quality improvement

Functional and anatomical evaluation of the effect of nepafenac in prevention of macular edema after phacoemulsification in diabetic patients

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International Journal of Ophthalmology(English edition) 2019年第3期12卷 387-392页

作者： Tharwat mokbel Sameh Saleh mona Abdelkader Sherief E.el-khouly Waleed Abou Samra mohamed mamdouh mansoura Ophthlmic Center Faculty of Medicine Mansoura University

AIm: To evaluate the effect of prophylactic administration of nepafenac in prevention of macular edema occurring in diabetic patients after phacoemulsification and to investigate the correlation between optical coherence tomography(OCT) foveal thickness and multifocal electroretinogram(mF-ERG) ***: The study included two groups. Group 1 included 50 diabetic patients with senile cataract(50 eyes, 30 females, 20 males, aged 55±7 y) received nepafenac 0.1% eye drop. Group 2 included another 50 diabetic patients with senile cataract(50 eyes, 22 female, 28 males, aged 53.8±8 y) did not receive nepafenac. All patients were followed up for 3 mo postoperatively. OCT and mF-ERG were done preoperative and at 1 wk, 1, 2 and 3 ***: The mean foveal thickness was statistically significantly lower in Group 1. Five eyes in Group 2 developed clinical cystoid macular oedema(CmO)(10%), and no patients in Group 1 developed central macular thickening more than 50 μm. There were insignificant differences in mF-ERG amplitudes and latencies between the two groups except in the five eyes that developed CmO, there statistically significant reduction of mF-ERG amplitude with increase in foveal thickness. CONCLUSION: Perioperative nepafenac reduces the incidence of CmO following uncomplicated phacoemulsification significantly. Nepafenac has no side effects.

关键词： nepafenac macular edema cataract surgery diabetes optical coherence tomography multifocal electroretinogram

Hypoglycemic and antioxidant activities of Caesalpinia ferrea martius leaf extract in streptozotocininduced diabetic rats

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Asian Pacific Journal of Tropical Biomedicine 2015年第6期5卷 460-470页

作者： Sherien Kamal Hassan Nermin mohammed el-Sammad Amria mamdouh mousa maha Hashim mohammed Abd el Razik Hussein Farrag Amani Nassir eldin Hashim Victoria Werner Ulrike Lindequist mahmoud Abd el-moein Nawwar Departement of Biochemistry National Research CentreCairo Egypt Departement of Pathology National Research CentreCairo Egypt Departement of Phytochemistry and Plant Systematics National Research CentreCairo Egypt Institute of Pharmacy Pharmaceutical Biology Ernst-Moritz-Arndt-Universitt GreifswaldD-17487 Greifswald Germany

Objective: To evaluate the antidiabetic and antioxidant ef ects of aqueous ethanolic extract of Caesalpinia ferrea(C. ferrea) leaf in normal and streptozotocin(STZ) induced diabetic ***: male Sprague-Dawley rats divided into 6 groups of 6 rats each were assigned into diabetic and non-diabetic groups. Diabetes was induced in rats by single intraperitoneal administration of STZ(65 mg/kg body weight). C. ferrea extract at the doses of 250 and 500 mg/kg body weight was orally administered to both diabetic and non-diabetic animals for a period of 30 days. After completion of experimental duration serum, liver and pancreas were used for evaluating biochemical and histopathological ***: Oral administration of C. ferrea leaf extract significantly reduced elevated serum glucose, α-amylase, liver function levels and signii cantly increased serum insulin, total protein and body weight as well as improved lipid proi le due to diabetes. Furthermore, the treatment resulted in a marked increase in glutathione peroxidase, superoxide dismutase, catalase and reduced glutathione, and diminished levels of lipid peroxidation in liver and pancreas of diabetic rats. Histopathological studies demonstrated the reduction in the pancreas and liver damage and coni rmed the biochemical i ***: From the present study, it can be concluded that the C. ferrea leaf extract ef ectively improved hyperglycaemia while inhibiting the progression of oxidative stress in STZ-induced diabetic rats. Hence, it can be used in the management of diabetes mellitus.

关键词： Caesalpinia ferrea Diabetes Streptozotocin Hypoglycemia Antioxidant markers Histopathology

Influence of Boron additions on mechanical Properties of Carbon Steel

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Journal of minerals and materials Characterization and Engineering 2012年第10期11卷 995-999页

作者： Saeed N. Ghali Hoda S. el-Faramawy mamdouh m. Eissa Steel Technology Department Central Metallurgical Research & Development Institute (CMRDI) Helwan Cairo Egypt

This work aims at the development of carbon steel AISI 1536 through the microalloying addition of boron. Three grades of this steel with different content of boron up to 0.0055% were melted in 100 kg induction furnace. The pro- duced steels were hardened at 960°C for 30 min., followed by tempering at different temperatures and durations. All hardened steels have martensite phase as illustrated with microstructures and X-ray diffraction. Hardness of all tem- pered steel samples was measured to calculate the activation energies of carbon migration through martensite phase. The results indicated that the activation energies of carbon migration through martensite phase decreases with the in- crease of boron content due to its positive effect on the crystallinity of martensite phase. Also, the results showed that the addition of boron up to 0.0023% can improve the steel properties at the lowest temperature and tempered time.

关键词： Boron Steel microalloy Activation Energy Carbon migration martensite

Postoperative Radiotherapy in Bladder Cancer Patients: 5-Year Institutional Experience of National Cancer Institute, Cairo University

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Journal of Cancer Therapy 2015年第7期6卷 579-593页

作者： Azza m. Nasr magda el mongi mamdouh Hagag manar m. moneer Hisham el Hossieny Azza Taher Sherif magdy Radiation Oncology Department National Cancer Institute Cairo University Giza Egypt Clinical Oncology Department Faculty of Medicine Cairo University Giza Egypt Cancer Epidemiology and Biostatistics Department National Cancer Institute Cairo University Giza Egypt

Purpose: adjuvant radiation therapy could reduce loco regional failure, but currently has no defined role because of previously reported morbidity. NCI-Cairo routine work is to give adjuvant PORT for locally advanced bladder carcinoma patients. The aim of this work is to re-evaluate this protocol regarding its effect on prognosis and complications. Patients and method: A retrospective study included 208 patients with pathologically proven bladder cancer who presented to the NCI, Cairo University from 2007-2011. All of them underwent RC with bilateral PLND followed by conventional post-operative radiotherapy in 2 - 6 weeks after surgery for 5000 cGy in 25 fractions, over 5 weeks using 2D technique. Analysis of data from their files was done for the treatment results, prognostic factors and complications. Results: Three years overall survival (OS) and disease free survival (DFS) for the whole group was ~60%, and 54% respectively in favour of the female gender, non-smokers, Squamous cell carcinoma patients, low grade tumours (grade 1 and 2) negative margins, N0, pT2b and early stage group showed the best prognoses. The 3 years metastases free survival (mFS) was ~71%. Only four factors showed a significant relation with the mFS which were the grade, LN status, T-stage and group staging. The local recurrence rate (LRC) at 2 years for the whole group was ~95% and 94% at 3 years. Only surgical margin status and extent of LN dissection had a significant impact on the LRC. Conclusions: adjuvant radiotherapy shows sustained improvement in the loco regional control, and should be recommended for patients with locally advanced disease especially those with less than 10 dissected lymph nodes and those with positive margins.

关键词： Bladder Cancer Radiotherapy Pelvic Irradiation

Effect of Titanium addition on Behavior of medium Carbon Steel

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Journal of minerals and materials Characterization and Engineering 2012年第11期11卷 1108-1112页

作者： Hoda S. el-Faramawy Saeed N. Ghali mamdouh m. Eissa Steel Technology Department Central Metallurgical R & D Institute (CMRDI) Cairo Egypt

This work aims at investigating the influence of titanium addition on behavior of medium carbon steel. Three types of medium carbon steel with different titanium content and one reference steel titanium free were produced in 100 kg induction furnace. Titanium addition was increased up to 0.230%. The produced steels were forged at start temperature 1150°C. Forging process was finished at temperatures 900°C, 975°C, and 1050°C. microstructure examination and hardness measurement were carried out for forged steels. mechanical properties and impact measurements were carried out for quenched tempered steels. Ti addition was found to have significant influence on refinement of grains and increase of ferrite/pearlite ratio. It was also, observed that grain size decreases as finishing temperature of forging process decreases. Both Ti addition and lowering finishing forging temperature have positive effect on hardness. In addition, results indicated that addition of titanium has significant effect on the mechanical properties and toughness.

关键词： Titanium Refinement Ferrite Pearlite Forging

electroslag Refining of CrNimoWmnV Ultrahigh-Strength Steel

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Journal of minerals and materials Characterization and Engineering 2017年第6期5卷 385-407页

作者： mohammed Ali mamdouh Eissa Hoda el Faramawy David Porter Jukka K&ouml mi m. F. el-Shahat Taha mattar materials Engineering and Production Technology University of Oulu Oulu Finland Steel Technology Department Central Metallurgical Research and Development Institute Cairo Egypt Chemistry Department Ain Shams University Cairo Egypt

Increasing demands for ultrahigh-strength steels in commercial as well as military applications have raised interest in finding alternatives to the high-cost high-alloyed steel and super-alloys currently used, e.g. the use of economic low-alloy compositions processed via low-cost air induction melting and electroslag refining (ESR). In this work the yield of alloying elements and the removal of the impurities nitrogen, sulphur and phosphorus as a result of electroslag refining (ESR) in a newly developed CrNimoWmnV ultrahigh-strength steel (UHSS) have been studied in relation to their activities in the molten metal pool. Six experimental heats of CrNimoWmnV UHSS with different chemical compositions were designed, melted in an induction furnace (IF) and refined using ESR. This was followed by hot forging of the ingots at 1100°C to 950°C. ESR using a CaF2-CaO-Al2O3 slag system led to a high yield in Cr, Ni, mo, W, mn and V, while the yield of Si is low. The desulphurization of all six UHSS grades was pronounced with most of the sulphur removed either to the slag or by gas reactions. The degree of dephosphorization was only 5% irrespective of the steel composition. On the other hand, denitrification (removal of nitrogen) was achieved. It ranged from 8% to 63% depending on the steel composition. The yield of the alloying elements and removal of impurities from the steel during ESR depends on the chemical and physical properties of the ESR slag and the activity of the elements in the molten state, taking into account elemental interactions.

关键词： Ultrahigh-Strength Steel electroslag Refining Alloying elements Impurities Activity