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Statistical Analyses and Geotechnical Evaluation of Nubia Sandstone, Golden Triangle Area, Egypt

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Journal of Geoscience and Environment Protection 2021年第11期9卷 46-60页

作者： hesham ahmed Hussein Ismaiel Mohamed Mohamed Askalany Ali Ismail Ali Department of Geology Faculty of Science South Valley University Qena Egypt

Great efforts had been made to use indirect non-destructive tests in the geotechnical evaluation of rocks, especially sandstones, employing different empirical equations. However, most of these equations have been derived from hard and compacted sandstones data;therefore, the focus of this research is on weak and weakly compacted sandstones, aiming firstly to obtain empirical equations for estimating their characteristics, secondly to demonstrate and visualize the correlations between the studied variables, and finally to cluster the studied samples based on their characteristics. To attain these aims, twenty oriented block samples were collected from Nubia sandstone, central Eastern Desert, Golden Triangle area, Egypt. These samples were prepared and tested according to standard test methods, including uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), Schmidt rebound number (SRN), porosity (n), bulk density (ρ), and ultrasonic P-wave velocity (UPV). The loss on ignition (LOI) was also employed as a physicochemical test for classifying the studied samples and indicating pores filling materials. The results revealed that these sandstones are characterized mainly by high n, low ρ, and low UPV values and these give an indication of weakly compacted and weakly cemented sandstone with shallow burial diagenetic conditions. Based on UCS and elastic modulus values, these sandstones are mainly classified as very low strength and highly yielding rocks. The results of regression analysis show satisfactory correlations between physical and mechanical characteristics, indicating the suitability of obtained empirical equations to deduce these properties. Principal component analysis revealed that the LOI, BTS, SRN, and US

关键词： Geotechnical Evaluation Empirical Equations Statistical Analyses Nubia Sandstone Non-Destructive Test

Synthesis of Some New Diazo Disperse Dyes and Their Application on Dyeing of Polyester

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Journal of Chemistry and Chemical Engineering 2011年第2期5卷 150-158页

作者： ahmed Zaky Sayed Mahmoud Sayed Aboul-Fetouh hesham Sayed Nassar Chemistry Department University College P.O.Box 2064Umm Al-Qura University Makkah Al-Mokaramah Al-Aziziah 21955 Saudia Arabia Chemistry Department Faculty of Science A l-Azhar University Cairo 11884 Egypt

The synthesis of some new diazo disperse dyes containing a pyrazol-5-one was described. The structures of the new products have been deduced from elemental analysis and spectral dada such as UV-Vis absorption, IR, ^1H NMR, and MS spectroscopy. These dyestuffs gave satisfactory results when applied as disperse dyes to polyester fabric. The dyeing properties such as light fasmess, washing fastness and exhaustion studies have been investigated.

关键词： Pyrazolin-5-one disperse dyes disazo dyes dyeing exhaustion fastness

One Stage Anterior Reconstruction and Posterior Instrumentation in Surgical Management of Thoracolumbar Spine Fractures

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Open Journal of Orthopedics 2015年第1期5卷 6-15页

作者： Khaled Omran hesham Ali ahmed Saleh ahmed Omar Ibrahim Elhawery Ali Zein A. A. Alkhooly Faculty of Medicine El-Minia University El-Minia Egypt

Background: The different methods of anterior reconstruction and posterior instrumentation in surgical management of thoracolumbar spine fractures are PLIF, TLIF, lateral extracaviatary and transpedicular techniques which are increasingly used to perform partial or total corpectomies and anterior reconstructions from a posterior approach. These techniques were being alternative to the standard anterior approach with less morbidity and mortality. Patients and Methods: This study was performed between 2011 and 2014 on 100 patients with acute unstable thoracolumbar spine fractures which were divided into four groups: 30 patients underwent (TLIF), 28 patients underwent (PLIF), 28 patients underwent (PA) and 14 patients underwent (TPA). Neurological outcome, complications, operative times, kyphotic angle, vertebral height loss, spinal canal compromise, pulmonary functions, Denis pain and work scale, VAS score, ODI score, hospital stay, and estimated blood loss (EBL) were evaluated and compared in between the four groups. Results: There was a higher complication rate, increased EBL, and longer operative time with posteroanterior (PA) compared with PLIF, TLIF and (TPA). Patients undergoing PLIF, TLIF and TPA had a greater recovery of neurological function than those in whom PA were performed. Conclusion: TPA appeared to have more favorable results in improving the clinical and radiological outcome and no complications were reported apart from superficial wound infection which healed rapidly. The PLIF, TLIF and TPA appeared to have a comparable morbidity rate to PA. The different methods of anterior reconstruction from posterior approach are more favorable, applicable and convenient than PA approach.

关键词： Transpedicular Approach (TPA) Postero-Anterior Approach (PA) Posterior Lumbar Interbody Fusion (PLIF) Transforminal Lumbar Interbody Fusion (TLIF)

Performance Enhancement for Adaptive Beam-Forming Application Based Hybrid PSOGSA Algorithm

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Journal of Electromagnetic Analysis and Applications 2015年第4期7卷 126-133页

作者： ahmed Magdy Osama M. EL-Ghandour hesham F. A. Hamed Department of Electrical Engineering Minia University Minia Egypt Department of Electronics Communications and Computer Engineering Helwan University Cairo Egypt

Recently researchers were interested in hybrid algorithms for optimization problems for several communication systems. In this paper, a novel algorithm based on hybrid PSOGSA technique (combination of Gravitational Search Algorithm and Particle Swarm Optimization) is presented to enhance the performance analysis of beam-forming for smart antennas systems using N elements for Uniform Circular Array (UCA) geometry. Complex excitations (phases) of the array radiation pattern are optimized using hybrid PSOGSA technique for a set of simultaneously incident signals. Our results have shown tremendous improvement over the previous work was done using Uniform Linear Array (ULA) geometry and standard GSA in terms of normalized array factor and computational speed for normalized fitness values.

关键词： Smart Antennas UCA Optimization Techniques Beam-Forming

Performance Analysis on a Dual External Cavity Tunable Laser ECTL Source

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Journal of Electromagnetic Analysis and Applications 2015年第4期7卷 134-139页

作者： ahmed Fawzy Osama M. El-Ghandour hesham F. A. Hamed Department of Electrical Engineering Minia University Minia Egypt Department of Electronics Communications and Computer Engineering Helwan University Cairo Egypt

This paper presents the diffraction effects on the performance of a dual external cavity tunable laser source, whose external cavities are constructed by micro electro mechanical systems (MEMS). One of the main problems in these structures is the optical diffraction as the emitting surface of the laser diode is usually quite limited in the transverse directions. The emitted beam diffracts rapidly in the air and only a small amount of light is coupled back to the source that usually limits the tuning range of the source. Device characteristics such as tuning range, wavelength shift and sensitivity are evaluated. New expression is used and multiple reflections inside external cavities are considered. The simulation results have shown that single external cavity has limited tuning range. It is shown that multiple reflections have significant effect in our model. To get a better engineering for the dual ECTL dimensions, diffraction effects must be taken into account.

关键词： External Cavity Laser Tunable Laser MEMS Optical Diffraction

Fabrication of Congo Red/Oxidized Porous Silicon (CR/OPS) pH-Sensors

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Materials Sciences and Applications 2013年第8期4卷 79-87页

作者： Abdel-Hady Kashyout hesham M. A. Soliman Marwa Nabil ahmed A. Bishara Advanced Technology and New Materials Research Institute City for Scientific Research and Technology Applications New Borg El-Arab City Alexandria Egypt Physics Department Faculty of Science Alexandria University Alexandria Egypt

The fabrication of nano porous silicon, nPSi, using alkali etching process has been studied and carried out. The surface chemistry of anisotropic etching of n-type Si-wafer is reviewed and the anisotropic chemical etching of silicon in alkaline solution using wetting agents is discussed. Transformation of crystallographic plane of n-Si (211) to nPSi (100) has occurred on using n-propanol as wetting agent. The rate of pore formation was 0.02478 - 0.02827 μm/min, which was heavily dependent upon the concentration of the etchant containing wetting agents, allowing patterned porous silicon formation through selective doping of the substrate. A particle size of 15 nm for porous nano-silicon was calculated from the XRD data. Porosity of PS layers is about 10%. Pore diameter and porous layer thickness are 0.0614 nm and 16 μm, respectively. The energy gap of the produced porous silicon is 3.3 eV. Furthermore, the combination of PS with Congo Red, which are nanostructured due to their deposition within the porous matrix is discussed. Such nano compounds offer broad avenue of new and interesting properties depending on the involved materials as well as on their morphology. Chemical route was utilized as the host material to achieve pores filling. They were impregnated with Congo Red, which gave good results for the porous silicon as a promising pH sensor.

关键词： Nano Porous Silicon Anisotropic Etching Process Alkali Etching Congo Red PH Sensor

Hydro Matrix Power Wheels Generate More than 5 GW/h from Main Branch Canals (River Nile) in Egypt

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Journal of Power and Energy Engineering 2016年第3期4卷 71-78页

作者： hesham F. A. Hamed ahmed M. Kassem Medhat E. M. Ali Faculty of Engineering Elminia University Minya Egypt Faculty of Engineering Sohag University Sohag Egypt

In this paper, a new hydromatrix power wheels generation unit is presented. This presented hydromatrix power unit is aimed to convert the water movement in the main river branches into electrical power. It is found that the generated power based on the proposed hydromatrix power can be generated about 5 GW/h in Egypt. The proposed hydromatrix power unit based on the under shot water wheel type and the generated electrical power using this proposed unit is calculated at head;difference equal to 1 meter is presented.

关键词： Hydromatrix Scheme Electrical Energy Development Electricity Renewable Energy Project Financing Egypt

Transabdominal Pre-Peritoneal Mesh for Inguinal Hernia Repair with External Fixation versus Mesh Stapling

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Surgical Science 2013年第11期4卷 516-519页

作者： Mohamed Abdelhamid ahmed Mohamed Sadat Ayman Refaat Abdelhaseeb Tamer Mohamed Nabil Mohamed Salah Abdelbasset Amro Mohamed Ali Bechet hesham ahmed Nafady Kalid ahmed Shawky Faculty of Medicine Bani Swif University Bani Swif Egypt

Background: It is unknown whether stapling the mesh affects recurrence rate, incidence of neuralgia, and port-site hernia. We chose to fix it to the exterior reducing port size, cost and pain, at the same comparing this with traditional mesh stapling. Methods: We conducted a prospective trial for laparoscopic TAPP inguinal hernia repair on 120 patients in which we fixed the mesh to the anterior abdominal wall using either two prolene threads that passed to the exterior and tied in place or traditional mesh stapling. Results: The operative time is ranged from 35 to 70 minutes for external fixation, 30 to 60 minutes for mesh stapling, and 4 to 51 months for follow-up, and no recurrence occurred in both groups during the procedure. Two cases with post TAPP pain in mesh stapling patients are discussed with reduction of the cost and port size in external fixation patients. Conclusion: It is not necessary to secure the mesh during laparoscopic TAPP inguinal hernia repair from the interior and it is fixed only to the exterior allowing a reduction in size of the ports and considerable reduction in cost with elimination of TAPP associated post operative pain.

关键词： Laparoscopic Transabdominal Preperitoneal Inguinal Hernia Repair Mesh Prosthesis Fixation Cost-Stapling

Structural, Magnetic and Dielectric Properties of Fe-Co Co-Doped Ba0.9Sr0.1TiO3Prepared by Sol Gel Technique

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New Journal of Glass and Ceramics 2014年第2期4卷 19-28页

作者： Inas Kamal Batttisha Ibrahim Sayed ahmed Farag Mostafa Kamal Mohamed Ali ahmed Emad Girgis hesham Azmi El Meleegi Fawzi Gooda El Desouky Materials Science Lab (1) Physics Department Faculty of Science Cairo University Giza Egypt Metal Physics Laboratory Physics Department Faculty of Science Mansoura University Mansoura Egypt National Research Center (NRC) Solid State Physics Department Dokki Giza Egypt National Research Centre (NRC) Thin Film Lab Electron Microscope Department Dokki Giza Egypt

The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x = 0.5, y = 0.5) in powder form, abbreviated as (BST) and (BST10FO), (BST10CO) and (BST5F5CO), respectively were prepared by a modified sol gel technique. Crystallization, surface morphology and electrical behavior of BST are improved by Fe3+ and Co2+ ions with optimized grain size. Phase identification by using X-ray diffraction and surface morphology will be studied by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM). Phase identification by using X-ray diffraction and surface morphology evaluation by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM) will be studied. The nano-scale presence and the formation of the tetragonal perovskite phase as well as the crystallinity were detected using the mentioned techniques. The dielectric properties of the prepared samples have been investigated as a function of temperature and frequency. The dielectric measurements are carried out in the frequency range of 42 Hz - 1 MHz, at temperature ranging between 25°C and 250°C. The results showed an abrupt decrease in the dielectric permittivity by increasing the frequency range. The magnetic hysteresis loop confirmed enhancement in the magnetization properties by co-doping with Fe3+-Co2+ ions. An increase in the saturation of the magnetization at room temperature was detected by decreasing the crystallite sizes of the prepared samples.

关键词： Sol Gel Nano-Structure Magnetic Hysteresis Loop Dielectric Permittivity Nano-Composite BaSrTiO3 (BST) TEM XRD SEM