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Search Results: 1 - 10 of 14090 matches for " Adel El-Shahat "
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Performance Investigation of Three Combined Airfoils Bladed Small Scale Horizontal Axis wind Turbine by BEM and CFD Analysis  [PDF]
Mehedi Hasan, Adel El-Shahat, Musfequr Rahman
Journal of Power and Energy Engineering (JPEE) , 2017, DOI: 10.4236/jpee.2017.55002
Abstract: The present work is based on the comparative study between “Blade-Element- Momentum” (BEM) analysis and “Computational-Fluid-Dynamics” (CFD) analysis of small-scale horizontal axis wind turbine blade. In this study, the pitch is considered as fixed and rotor speed is variable. Firstly, the aerodynamic characteristics of three different specialized airfoils were analyzed to get optimum design parameters of wind turbine blade. Then BEM was performed with the application of the open source wind turbine design and performance computation software Q-Blade v0.6. After that, CFD simulation was done by Ansys CFX software. Here, k-ω “Shear-Stress-Transport” (SST) model was conducted for three-dimensional visualization of turbine performance. However, the best coefficient of performance was observed at 6o angle of attack. At this angle of attack, in the case of BEM, the highest coefficient of performance was 0.47 whereby CFD analysis, it was 0.43. Both studies showed good performance prediction which was a positive step to accelerate the continuous revolution in wind energy sector.
Numerical and Experimental Investigation of Aerodynamic Performance of Vertical-Axis Wind Turbine Models with Various Blade Designs  [PDF]
Mosfequr Rahman, Travis E. Salyers, Adel El-Shahat, Marcel Ilie, Mahbub Ahmed, Valentin Soloiu
Journal of Power and Energy Engineering (JPEE) , 2018, DOI: 10.4236/jpee.2018.65003
Abstract: Due to the importance and advantages of Vertical-axis wind turbines (VAWTs) over traditional horizontal-axis wind turbines (HAWTs), this paper is implemented. Savonius turbines with drag-based rotors are adopted from the two more extensive arrangements of vertical wind turbines because of their advantages. In this paper, six diverse rotor plans with measure up to cleared regions are analyzed with exploratory wind burrow testing and numerical reenactments. These proposed models incorporate a conventional Savonius with two different edges criteria and 90 degree helical bend models with two, three and four sharp edges. The models were designed using SolidWorks software then the physical models were 3D printed for testing. A subsonic open-sort wind burrow was utilized for Revolution per Minute (RPM) and torque estimation over a scope of wind speeds. ANSYS Fluent reenactments were utilized for dissecting streamlined execution by using moving reference outline and sliding lattice display methods. A 3-dimensional and transient strategy was utilized for precisely tackling torque and power coefficients. The five new rotor geometries have important advantages such as making a focal point of weight advance from the hub of revolution and causing more noteworthy torque on the turbine shaft contrasted with the customary Savonius turbine. Our new models with the names of CC model and QM model display cross-areas lessen the aggregate scope of negative torque on the edges by 20 degrees, contrasted with the customary Savonius demonstrate. Helical plans are better spread the connected torque over a total transformation resulting in positive torque over every single operational point. Moreover, helical models with 2 and 3 cutting edges have the best self-starting ability in low wind speeds. Helical VAWT with 3 edges starts revolution of 35 RPM at only 1.4 m/s wind speed under no generator stacking. The most noteworthy power coefficient is accomplished, both tentatively and numerically, by the helical VAWT with 2 sharp edges.
Study the Entanglement Dynamics of an Anisotropic Two-Qubit Heisenberg XYZ System in a Magnetic Field  [PDF]
A. R. Mohammed, T. M. El-Shahat
Journal of Quantum Information Science (JQIS) , 2017, DOI: 10.4236/jqis.2017.74013
Abstract: We investigate the entanglement dynamics of an anisotropic two-qubit Heisenberg XYZ system with Dzyaloshinskii-Moriya (DM) interaction in the presence of both inhomogeneity of the external magnetic field b and intrinsic decoherence which has been studied. The behavior of quantum correlation and the degree of entanglement between the two subsystems is quantified by using measurement-induced disturbance (MID), negativity (N) and Quantum Discord (QD), respectively. It is shown that in the presence of an inhomogeneity external magnetic field occur the phenomena of long-lived entanglement. It is found that the initial state is the essential role in the time evolution of the entanglement.
Entanglement of Moving and Non-Moving Two-Level Atoms  [PDF]
Mohamad Kh. Ismail, Tarek M. El-Shahat
Journal of Quantum Information Science (JQIS) , 2017, DOI: 10.4236/jqis.2017.74014
Abstract: In this paper we study the dynamics of the atomic inversion, von Neumann entropy and entropy squeezing for moving and non-moving two-level atoms interacting with a Perelomov coherent state. The final state of the system using specific initial conditions is obtained. The effects of Perelomov and detuning parameters are examined in the absence and presence of the atomic motion. Important phenomena such as the collapse and revival are shown to be very sensitive to the variation of the Perelomov parameter in the presence of detuning parameter. The results show that the Perelomov parameter is very useful in generating a high amount of entanglement due to variation of the detuning parameter.
Removal of Cesium on Polyaniline Titanotungstate as Composite Ion Exchanger  [PDF]
I.M. El-Naggar, E. S. Zakaria, I. M. Ali, M. Khalil, M. F. El-Shahat
Advances in Chemical Engineering and Science (ACES) , 2012, DOI: 10.4236/aces.2012.21020
Abstract: Polyaniline titanotungstate (PATiW) was synthesized by the sol-gel method. Adsorption isotherm studies of Cs+ from aqueous solution are described. Elemental Composition, chemical solubility, ion-exchange capacity (IEC) and pH titration are studied. Distribution coefficients (Kd) for ten metal ions have been determined. It was found that the polyaniline titanotungstate has high affinity and high selectivity for Cs+. The material was high separation of Cs+ from other metal ions. The adsorbent capacity was determined using the Freundlich and Langmuir adsorption isotherm models. The Cs+ adsorption isotherm data fit best to the Freundlich isotherm model. The maximum Cs+ uptake of polyaniline titanotungstate was found 217 mg/g. A column tests were performed to determine the breakthrough curves with varying bed depths and flow rates in different solutions. The results show that the half breakthrough time increases proportionally with increasing bed depths. Kinetic studies for removal cesium from milk were investigated.
Suppression Effect of Superoxide Dismutase (SOD)-Like Activity Protein Partially Purified from Raphnus sativus Leaves against Liver Metastasis in Mice Intraperitoneally Infected with Ehrlich Ascites Carcinoma Cell  [PDF]
El-Shahat A. Toson, Fahed M. Almutairi, Amira Ali Elfalal, Salem A. Habib, Rasha F. Zahran, Mohamed Elbakry
Natural Science (NS) , 2016, DOI: 10.4236/ns.2016.87037
Abstract: Liver metastasis is a normal result in Ehrlich Ascites Carcinoma Cell (EAC) infected mice. A partially purified protein with Superoxide Dismutase (SOD)-like activity extracted from leaves of Raphnus sativus was tested for its ability to down regulate liver metastasis of Ehrlich Ascites Carcinoma Cell (EAC) intraperitoneally implanted in albino mice. Sixty albino mice were divided equally into 4 groups. Group I mice (G1 control) were treated with physiologic saline solution for 7 days. Group 2 mice (G2) were injected with the partially purified protein. Group 3 mice (G3) were intraperitoneally inoculated with EAC cells and treated with the partially purified protein. Group 4 mice (G4) were inoculated EAC cells and treated with physiologic saline solution. The results showed a disturbance in liver functions. This disturbance was observed as a reduction in the values of serum albumin, hemoglobin, total counts of erythrocytes and platelets, total lipids in liver tissues, erythrocytes SOD activity, serum glucose, reduced glutathione (GSH) and the trace elements (Fe, Mn, Zn, and Cu) contents in liver and spleen tissues as well as the elevation of serum transaminases activities, the levels of malondialdehyde in blood, DNA and RNA of liver tissues in the infected mice (G4). On the other hand, in G3, after treatment with the partial purified protein all these parameters restored their normal values and became near from the normal group (GI). Moreover, the protein showed no toxicity towards the mice as shown in G2. It could be concluded that a partially purified protein with Superoxide Dismutase (SOD)-like activity extracted from leaves of Raphnus sativus as a nature source has a promised future in controlling liver metastasis.
An Electron Microscopic Study of the Antifertility Potential of Rosemary (Rosmarinus officinalis L.) in Male Albino Rats
El-Din,Rania A. Salah; El-Shahat,Abd El-Rahman; Elmansy,Rasha Ahmed;
International Journal of Morphology , 2012, DOI: 10.4067/S0717-95022012000200051
Abstract: the present work was aimed at studying the antifertility potential of the commonly used herb, rosemary in the male albino rats using electron microscopy as the method of investigation. ethanolic extract of the rosmary prepared and administered orally in two different doses for a period of three months to the animals. at the end of the experiment animals were sacrificed and testes removed. sections for the electrone microscopy prepared and changes were observed. the present results showed evident microscopic changes in the testis of the animals received higher dose of the drug. most of the seminiferous tubules were compressed, having irregular basement membrane and devoid of any spermatogenic cells. the present work revealed a clear morphological evidence of the dose dependent antifertility potential of the rosemary in the male albino rats.
An Electron Microscopic Study of the Antifertility Potential of Rosemary (Rosmarinus officinalis L.) in Male Albino Rats Estudio de Microscopía Electrónica del Potencial Antifertilidad del Romero (Rosmarinus officinalis L.) en Ratas Macho Albinas
Rania A. Salah El-Din,Abd El-Rahman El-Shahat,Rasha Ahmed Elmansy
International Journal of Morphology , 2012,
Abstract: The present work was aimed at studying the antifertility potential of the commonly used herb, rosemary in the male albino rats using electron microscopy as the method of investigation. Ethanolic extract of the rosmary prepared and administered orally in two different doses for a period of three months to the animals. At the end of the experiment animals were sacrificed and testes removed. Sections for the electrone microscopy prepared and changes were observed. The present results showed evident microscopic changes in the testis of the animals received higher dose of the drug. Most of the seminiferous tubules were compressed, having irregular basement membrane and devoid of any spermatogenic cells. The present work revealed a clear morphological evidence of the dose dependent antifertility potential of the rosemary in the male albino rats. El trabajo tuvo como objetivo estudiar el potencial anti-fertilidad de la hierba de uso común, el romero, en ratas albinas macho utilizando microscopía electrónica como método de investigación. El extracto etanólico del romero se preparó y administró por vía oral a los animales en dos dosis diferentes durante un período de tres meses. Los animales experimentales se sacrificaron y se retiraron sus testículos. Se prepararon secciones para microscopía electrónica y se observaron los cambios. Los resultados mostraron cambios microscópicos evidentes en los testículos de los animales que recibieron una dosis mayor del medicamento. La mayoría de los túbulos seminíferos se observaron comprimidos, con una membrana basal irregular y carente de células espermatogénicas. El presente trabajo revela una clara evidencia morfológica de una posible anti-fertilidad dependiente de la dosis del romero administrada en las ratas albinas macho.
Helicobacter pylori and Hepatitis C virus coinfection in Egyptian patients
El-Masry Samir,El-Shahat Mohamed,Badra Gamal,Aboel-Nour Mohamed
Journal of Global Infectious Diseases , 2010,
Abstract: Introduction: Chronic hepatitis C virus (HCV) infection is a leading cause of end-stage liver disease worldwide. It has been shown that Helicobacter pylori (H. pylori) plays an important role in chronic gastritis, peptic ulcer disease and gastric malignancies, and its eradication has been advocated. The association between H. pylori infection and liver cirrhosis in patients with hepatitis C virus has been documented in different parts of the world; nevertheless, no conclusive data is available in Egypt. Materials and Methods: In the present study, the status of H. pylori infection was sought in 90 patients with chronic HCV infection and in 66 HCV-free healthy controls. Results: The study showed that the H. pylori positivity was increased significantly (P = 0.03) in the HCV-infected patients when compared to that in healthy controls, where H. pylori infection was found in 50 (55.6%) out of 90 of the HCV-infected patients versus 26 (39.4%) out of 66 of the healthy controls. In HCV-infected patients, the prevalence of H. pylori infection was increased significantly (P = 0.04) from chronic active hepatitis to cirrhosis. H. pylori infection was present in 6/18 (33.3%), 10/21 (47.6%), 16/27 (59.3%), 18/24 (75.0%) patients with chronic active hepatitis, Child-Pugh score A, Child-Pugh score B and Child-Pugh score C, respectively. More importantly, the prevalence of H. pylori infection in HCV-infected patients was increased very significantly (P = 0.003) with increasing Meld (model for end-stage liver disease) score. The prevalence of H. pylori was documented in 9/28 (32.1%) patients with Meld score ≤10 and in 41/62 (66.1%) patients with Meld score> 10. Conclusion: It may be stated that our results collectively reflect a remarkable increase in H. pylori prevalence with advancing hepatic lesions, and the eradication treatment may prove beneficial in those patients with chronic hepatitis C.
Hypertension in UAE Citizens - Preliminary Results of a Prospective Study
El-Shahat Yassin Ibrahim,Bakir Sherif,Farjou Nizar,Hashim Tareq
Saudi Journal of Kidney Diseases and Transplantation , 1999,
Abstract: This report from the National Epidemiological Study of Hypertension in the United Arab Emirates (NESH-UAE) represents the preliminary results of phase I, comprising the prevalence, awareness, treatment and control of hypertension among UAE citizens (adults aged 18-75 years). The data reported in this study represent only the region of the Sharjah district, UAE. There were 3150 individuals enrolled for the study. Hypertension was defined as systolic pressure > 140 mmHg, and/or diastolic pressure> 90 mmHg, and/or reported treatment with one or more antihypertensive medications. The overall prevalence in this screened sample was 36.6%. Most of the study subjects were in the productive age, from 30-50 years. In the hypertensive group there are more females than males (53% vs. 47% respectively). Overall, 26% of hypertensive persons were aware that they had high blood pressure, 41% being treated with antihypertensive medications, and 19 % were under control (systolic pressure < 140 and diastolic pressure < 90 mmHg). We plan to extend the study to other regions in the country in order to attain a representative sample and results about this disease. These preliminary results indicate that hypertension is highly prevalent in the UAE. The rates of awareness, treatment and control are relatively low. Furthermore, they argue for a nation-wide effort to prevent and control high blood pressure in the UAE in order to prevent the related complications.
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