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New Approach to Modeling a Solar Cell in Relation to Its Efficiency—Laplace Transform Technique

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Optics and Photonics Journal 2014年第8期4卷 219-227页

作者： mohamed abdelhady kamel el-adawi Ibtissam Abdelrahman Al-Nuaim Physics Department Faculty of Education Ain Shams University Heliopolis Cairo Egypt Physics Department Faculty of Science for Girls Dammam University Saudi Arabia

Heating a solar cell subjected to incident solar irradiance is studied. Laplace Integral Transform technique is applied to get the temperature field within the cell. The efficiency as a function of the cell temperature is estimated, and its variation with the local day time is thus clarified. Different cooling levels are considered. An illustrative example is given. The results show that the diurnal temperature variation of the cell is significant, while the efficiency is revealed to be a slowly varying function of temperature along the day time. It is revealed that as the temperature of the cell increases the efficiency decreases. Thus shading and cooling conditions may be useful to increase its efficiency.

关键词： Solar Cell Efficiency Temperature Field within a Solar Cell Laplace Transform Technique

Diffusion Equations of the electric Charges and Magnetic Flux

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Journal of electromagnetic Analysis and Applications 2024年第5期16卷 69-83页

作者： Salama abdelhady mohamed S. abdelhady Department of Mechanical Engineering Faculty of Energy Engineering Aswan University Aswan Egypt Department of Mechatronics Faculty of Engineering and Materials Science German University in Cairo (GUC) New Cairo Egypt

Innovative definitions of the electric and magnetic diffusivities through conducting mediums and innovative diffusion equations of the electric charges and magnetic flux are verified in this article. Such innovations depend on the analogy of the governing laws of diffusion of the thermal, electrical, and magnetic energies and newly defined natures of the electric charges and magnetic flux as energy, or as electromagnetic waves, that have electric and magnetic potentials. The introduced diffusion equations of the electric charges and magnetic flux involve Laplacian operator and the introduced diffusivities. Both equations are applied to determine the electric and magnetic fields in conductors as the heat diffusion equation which is applied to determine the thermal field in steady and unsteady heat diffusion conditions. The use of electric networks for experimental modeling of thermal networks represents sufficient proof of similarity of the diffusion equations of both fields. By analysis of the diffusion phenomena of the three considered modes of energy transfer;the rates of flow of these energies are found to be directly proportional to the gradient of their volumetric concentration, or density, and the proportionality constants in such relations are the diffusivity of each energy. Such analysis leads also to find proportionality relations between the potentials of such energies and their volumetric concentrations. Validity of the introduced diffusion equations is verified by correspondence their solutions to the measurement results of the electric and magnetic fields in microwave ovens.

关键词： Diffusion Coefficient Diffusion Equation electric Charge Magnetic Flux electromagnetic Waves electric Field Magnetic Field

Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors

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Computers, Materials & Continua 2023年第3期74卷 5229-5250页

作者： mohamed elnagi Salah kamel abdelhady Ramadan mohamed F.elnaggar Department of electrical Engineering Faculty of EngineeringAl-Azhar UniversityQena83518Egypt Department of electrical Engineering Faculty of EngineeringAswan UniversityAswan81542Egypt Department of electrical Engineering College of EngineeringPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Department of electrical Power and Machines Engineering Faculty of EngineeringHelwan UniversityHelwan11795Egypt

Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy *** is evident in the advancement of scientific research aimed at improving solar cell *** to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this *** a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid *** this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise *** each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local *** INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional *** outcomes of all applications are examined and compared to several recent *** well as the results are evaluated through statistical *** results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms.

关键词： Photovoltaic(PV)modules weIghted meaN oF vectOrs algorithm(INFO) renewable energy static PV models dynamic PV models solar energy

An Entropy Approach to the Natures of the electric Charge and Magnetic Flux

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Journal of electromagnetic Analysis and Applications 2015年第11期7卷 265-275页

作者： Salama abdelhady mohamed S. abdelhady Faculty of Energy Engineering Aswan University Aswan Egypt Department of Mechanical Engineering Beni-Suef University Beni-Suef Egypt

As a result of investigating analytically and experimentally the interchangeability between thermal, electrical and magnetic energies, it is proved in the presented study that the electric and magnetic energies have an equivalent grade and nature as the thermal energy. So, the natural flow of electric charges and magnetic flux is associated also by increase of entropy of universe, similar to the heat, and has the same nature of waves as the electromagnetic heat radiation. Casting the Maxwell’s wave equation into an energy frame of reference that replaces the time in wave equations by entropy, it is possible to represent the electric charges and magnetic flux as electromagnetic waves of electric and magnetic potentials. Such results lead to modify exclusively the definition of the physical nature of the electric charge and magnetic flux which is unavailable in literature.

关键词： Heat electric Current Magnetic Flux Entropy electromagnetic Waves Maxwell’s Wave Equation

Nano-copper Oxide as Catalyst for Click Reactions

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Journal of Chemistry and Chemical Engineering 2016年第7期10卷 341-346页

作者： Reda abdelhady Mustafa elKhashab Abdelaziz Ahmed Nayl elsayed mohamed Badawy TamerAbdelmoemen el Malah Chemistry Department College of Science Aljouf University Sakaka Kingdom of Saudi Arabia National Center for Clinical and Environmental Toxicology Faculty of Medicine Cairo University Cairo Egypt Hot Laboratories Centre Atomic Energy Authority Cairo P.O. 13 759 Egypt Photochemistry Department National Research Centre 33 E1Buhouth Street PO 12622 Dokki Giza Egypt

Click reactions are not specific reactions, but they are a way of generating products that follow examples in nature by joining small moieties, with each other producing a huge molecule in a good yield. The mind of that reaction is used in biomolecules synthesis, pharmacological and various biometric applications. The first Click reaction is the Copper compounds-catalyzed reaction of an azide with an alkyne （CuAAC）, this copper-catalyzed ＂click＂ does not require legands on the metal but the metal oxides also can accelerate the reactions. For enhancement the products of Click reactions we were replacing the copper compounds in a classical reaction by the prepared nanocopper compound （NPs）. And measure the consumption of starting material. Behind the evolution is the catalytic effect of nanocopper compounding （NPs） on （H2O2）. Owing to the huge surface area of nanocopper compound （NPs）, it was found that： the （NPs） can speed up decomposition of H2O2, also can accelerate the classical click reaction.

关键词： Nanocopper oxide click reactions catalysis hydrogen peroxide.

Forced Convection Flow of Nanofluids Past Power Law Stretching Horizontal Plates

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Applied Mathematics 2012年第2期3卷 121-126页

作者： Fekry mohamed Hady Fouad Sayed Ibrahim Hassan Mohammed Hassan el-Hawary Ahmed Mostafa abdelhady Department of Mathematics Faculty of Science Assiut University Assiut Egypt

In the present work, we studied a nonsimilar solution of steady forced convection boundary layer flow and heat transfer of a nanofluid past a stretching horizontal plate. One-phase model has been used for this study. The nonsimilarity equations are solved numerically. We considered a nanofluid consists of AL2O3 as a nanoparticles and water as a base fluid. The volume fraction of nanoparticles is considered in the range 0 ≤ ? ≤ 0.2. with prandtl number pr = 6.2 for the water working as a regular fluid. The parameters which governing the solution are volume fraction of nanoparticles , stretching plate parameter ξ and power law index N. We investigated the effect of these parameters on the skin friction coefficient, Nusselt number, velocity and temperature profiles. We found that heat transfer rate and skin fraction increased when ? increased. On the other hand, we concluded that the increase in ξ and N made heat transfer rate increases and skin fraction decreases.

关键词： Forced Convection Nanofluid Nonsimilar Solution Heat Transfer Component

Assessment of Heavy Metals Pollution of Some Water Resources (Kafr el-Dawar—Egypt)

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Natural Resources 2017年第4期8卷 306-319页

作者： Abdrabelnabi mohamed abdelhady el-Hady E. F. Abdelaty, A. E. Boder Department of Natural Resources & Agricultural Engineering Agriculture Faculty Damanhour University Damanhour Egypt

Kafr el-Dawar is a major industrial city and a municipality on the Nile Delta in northern Egypt. Kafr el-Dawar area is unfortunately suffering from many factories that let out their waste water into the irrigation canal and agricultural drains. Twenty five water samples were collected from five water resources to assess their heavy pollution. The determination of heavy metals (HV) water resources content conducted to compose the following increasing HV concentration sequences;Drain Abu Qir (DA): Min (Cu)_Max (Zn), Canal Dbora Deufsho (CD): Min (Cu)_Max (Zn), Drain Dbora Abu Qir (DD): Min (Cu)_Max (Fe), Drain Kafr Dawar Deufsho (DK) : Min (Cu)_Max (Mn) and Drain Yarn and Fabric (DY) Min (Cu)_Max (Zn). Distribution patterns of HV concentration of water resources were (a) wide spread-distribution (Cr, Co, Mn), (b) moderately spread distribution pattern (Cu, Ni, Pb),and (c) narrow spread distribution pattern (Fe, Cd, Li and Zn) . The association study conducted to classify the HV concentration into three groups;positively highly correlated HV: (Pb_Cd), (Pb_Co), (Pb_Cr), (Cd_Co), (Zn_Fe), (Cr_Co), (Ni_Co) and (Ni_Fe), negatively highly correlated HV: (Pb_Mn), (Cd_Mn), (Mn_Cu) and (Co_Li) and intermediate cases (non-significant positive and negative intercorrelation) that was represented by the other cases. The low values of contamination factor, of short term use (CfiST), showed that the majority of HV concentration, of the studied water resources was at safe use level. This certainly with exception of the cases of cadmium that classified the water resources DA and CD, and DD into polluted and risky levels, respectively. The high values of contamination factor, of long term use (CfiLT), indicated that the studied water resources were mainly contaminated by Cd, Co and Cr heavy metals. Contrary, the low values of (CfiLT) of Zn, Fe, Li, Ni, Pb and Cu, all studied water resources are safe. Contamination degree index (Cd) indicated the safe use at short term of water resource

关键词： Heavy Metals Water Pollution Increasing Concentration Sequence Contamination Factor Kafr el-Dawar

Total Phenolic Content and Antioxidant Activity of Standardized Extracts from Leaves and Cell Cultures of Three Callistemon Species

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American Journal of Plant Sciences 2011年第6期2卷 847-850页

作者： mohamed I. S. abdelhady Amira Abdel Motaal Ludger Beerhues 不详

A comparative study was carried out with ethanolic (80%) extracts from leaves and cell cultures of three Callistemon species, namely C. lanceolatus (CL), C. viridiflorous (CV), and C. comboynensis (CC). Cell suspensions of the three species were grown in liquid Murashige and Skoog (MS) medium (100 ml) supplemented with 0.9 mg·g-1 kinetin in combination with 1.1 mg·g-1 NAA. The CL leaf extract was standardized to contain the highest amount of phenolics (104 ± 2.0 mg·g-1), followed by CC (95.8 ± 1.2 mg·g-1) and CV (79.8 ± 4.6 mg·g-1). On the other hand, cell cultures of CV contained more phenolics (14.9 ± 0.6 mg·g-1) than those of the other two species, CL and CC, which contained 12.2 ± 0.16 and 9.12 ± 0.16 mg·g-1, respectively. Nevertheless, CV leaf extract exhibited the highest antioxidant activity (91.4% ± 0.4%) at a concentration of 1000 μg·ml-1, comparable to 100 μg·ml-1 gallic acid (90.8% ± 1.5%).

关键词： Callistemon Phenolic Content Antioxidant Activity Callus Cell Cultures

Outcome of Laparoscopic Resection for Left Sided Colon and Rectal Cancer

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Journal of Cancer Therapy 2017年第1期8卷 51-63页

作者： Hamdy abdelhady Taha A. Esmail mohamed A. Hablus Osama Hassan Mahmoud elsherif mohamed M. elshheikh General Surgery Department Tanta Faculty of Medicine Tanta Egypt

Background: For many years, traditional surgery for left colon and rectal cancers had developed with variable degrees of morbidity. With the evolution of laparoscopy and by the aid of better visualization and magnification, laparoscopic colorectal surgery had appeared, but technically challenging as it involves almost all advanced laparoscopic techniques, with the benefits of minimal morbidity, less pain, earlier recovery, shorter hospital stay, without compromising oncological results. Aim: The aim of this work was to evaluate laparoscopic resection for left sided colon and rectal cancer as regard feasibility, safety and outcomes. Patients and Methods: This prospective study was conducted on 40 patients having left sided colon and rectal cancer, including 29 patients with rectal cancer and 11 patients with left sided colon cancer within the inclusion criteria are evaluated by clinical examination, radiological and colonoscopic study and biopsy and treated by laparoscopic resection and followed ranged from 6 months to 2 years with mean of 20 months. Results: Twenty seven patients (67.5%) underwent laparoscopic anterior resection, 11 patients (27.5%) underwent laparoscopic left hemicolectomy and only 2 patients (5%) underwent laparoscopic abdominoperineal resection, minimal morbidity, no cancer related mortality and no recurrence during the period of follow up either local or systemic. Conclusion: Laparoscopic resection for left sided colon and rectal cancer is technically feasible, oncologically safe and has more benefits on postoperative recovery.

关键词： Laparoscopic Colorectal Surgery