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Search Results: 1 - 10 of 9190 matches for " Mohamed Fahmy Raslan "
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Mineralogical and geochemical characteristics of uranium-rich fluoriteinEl-Missikat mineralized granite,Central Eastern Desert, Egypt
Mohamed Fahmy Raslan
Geologija , 2009,
Abstract: A unique, highly radioactive variety of fluor it emineral has been recorded in the uranium occurrence of El-Missikat sheared granite pluton. In this occurrence, the uranium assumes different forms, including its presence as discrete, visible, secondary minerals, rare uraninite and its association with the jasperoid and silica veinlets. However,in some other parts of the sheared zone, the uranium was found to be solely incorporated with fluorite crystals,filling veinlet sand fractures with out any other manife station.This paper focuses ont her elevant mineralogical and geochemical characteristics of this unique fluorite variety.In addition to an investigation with binocular and polarizing microscopes, the separated fluorite grains were analyzed usingan environmental scanning electronmicroscope(ESEM) and a field-emission scanning electron microscope.In addition to this,some fluorite crystals were subjected to electron microprobe analyses. While the fluorite accounted for as much as 20% of the sheared granite samples studied, it was found to range from 82 to 96 % in the different size fractions of the separated heavy mineral content. In some parts of the separated fluorite crystals,uranium inquantities of up to 2200 ppm was found to be heterogeneously distributed in the fluoritelattice,regardless of its coloration.
Mineralogy and mineral chemistry of rare-metal pegmatites at Abu Rusheid granitic gneisses, South Eastern Desert, Egypt
Mohamed Fahmy Raslan,Mohamed A. Ali
Geologija , 2011,
Abstract: The Abu Rushied area, situated in the South Eastern Desert of Egypt is a distinctive occurrence of economically important rare-metal mineralization where the host rocks are represented by granitic gneisses. Correspondingly, mineralogical and geochemical investigation of pegmatites pockets scattered within Abu Rusheid granitic gneisses revealed the presence of Hf-zircon, ferrocolumbite and uranyl silicate minerals (uranophane and kasolite). Electronmicroprobe analyses revealed the presence of Nb-Ta multioxide minerals (ishikawaite, uranopyrochlore, and fergusonite), uraninite, thorite and cassiterite as numerous inclusions in the recorded Hf-zircon and ferrocolumbite minerals.Abu Rusheid pegmatites are found as small and large bodies that occur as simple and complex (zoned) pegmatites.Abu Rusheid rare-metal pegmatites occur as steeply dipping bodies of variable size, ranging from 1 to 5 m in width and 10 to 50 m in length. The zoned pegmatites are composed of wall zone of coarser granitic gneisses, intermediated zone of K-feldspar and pocket of mica (muscovite and biotite), and core of quartz and pocket ofmica with lenses of rare metals.The zircon is of bipyramidal to typical octahedral form and short prisms. Because the zircon of the investigated Abu Rushied pegmatite frequently contains hafnium in amounts ranging between 2.31 and 11.11%, the studied zircon was designated as Hf-rich zircon. This zircon commonly exhibits a normal zoning with rims consistentlyhigher in Hf than cores. The bright areas in the crystal either in core or rim showed a remarkable enrichment in hafnium content (8.83–11.11%) with respect to the dark zones (3.19%). The investigated ferroclumbite commonly exhibits zoning; the dark zone is low in the Ta and U but the light zone is enriched in Ta (13%) and U (1%). EMPAanalyses indicate the chemical composition of ishikawaite with U ranging from 0.68 to 0.79 per formula unit.Uranopyrochlore species has dominant uranium in the A-site where it ranges from 12.72 to 16.49% with an average of 14.84%. The calculated formula of the studied fergusonite is A(Y0.303 ΣREE0.014 U0.135 Th0.063 Ca0.013 Pb0.006 Si0.213 Zr0.035 Hf0.048 Fe0.105)Σ0.935 B(Nb0.61 Ta0.084 Ti0.01)Σ0.704 O4.The presence of uraninite (high Th, and REE contents) and thorite, indicates that these minerals magmatic processes and followed by hydrothermal processes which are responsible for the precipitation of Nb-Ta multioxide minerals. Uranophane and kasolite of Abu Rusheid pegmatites are most probably originated from hydrothermalalterations of the primary uraninite. Abu Rushied
Influence of Inhomogeneity and Initial Stress on the Transient Magneto-Thermo-Visco-Elastic Stress Waves in an Anisotropic Solid  [PDF]
Mohamed Abdelsabour Fahmy
World Journal of Mechanics (WJM) , 2011, DOI: 10.4236/wjm.2011.15032
Abstract: The object of the present paper is to study the transient magneto-thermo-visco-elastic stresses in a non-ho- mogeneous anisotropic solid under initial stress. The system of fundamental equations is solved by means of a dual reciprocity boundary element method (DRBEM). In the case of plane deformation, a numerical scheme for the implementation of the method is presented and the numerical computations are presented graphically to show the effects of initial stress and inhomogeneity on the displacement components and thermal stress components.
Optimization of Renewable Energy Power System for Small Scale Brackish Reverse Osmosis Desalination Unit and a Tourism Motel in Egypt  [PDF]
Faten Hosney Fahmy, Ninet Mohamed Ahmed, Hanaa Mohamed Farghally
Smart Grid and Renewable Energy (SGRE) , 2012, DOI: 10.4236/sgre.2012.31006
Abstract: The main objective of this work is to design an optimal—efficient economic power renewable energy system that feeds the required electric load of a small scale brackish reverse osmosis desalination unit and a tourism motel located in Hurghada, Egypt. Four renewable energy power systems are presented in this paper to select the most optimum one of them. These suggested renewable energy systems are PV-wind hybrid system, stand-alone wind system, stand-alone photovoltaic system and PV-wind-fuel cell hybrid system. The sizing, optimization and economic estimation of the proposed systems were performed using HOMER software. HOMER solves the optimization problem to minimize the global cost and provides the optimum wind turbine, PV, battery and fuel cell ratings. In addition, a comparison between the four different suggested power system configurations is illustrated in details. PV-wind hybrid system realized the lowest net present cost and levelized cost of energy. Also, this system was able to provide energy approximately all the day. The battery state of charge varies between 83% and 99% and it was found that, the PV-wind hybrid system is more suitable than the others for the selected site and the suggested electrical load.
Paraoxonase 2 Gene (Cys311-Ser) Polymorphism and the Risk of Coronary Artery Disease  [PDF]
Mohamed Fahmy Elnoamany, Ashraf Abdelraouf Dawood, Rania Mohamed Azmy
World Journal of Cardiovascular Diseases (WJCD) , 2014, DOI: 10.4236/wjcd.2014.49056
Abstract:

Background: Human paraoxonase-2(PON2) which is exclusively intracellular possesses unique properities that distinguish it from PON1 and PON3. Recently, it was demonstrated that PON2 protects against atherosclerosis by preventing LDL oxidation. Emerging evidences have proposed that genetic variations in the PON2 gene may be associated with coronary artery disease (CAD). Objectives: To investigate the relationship between a common PON2 gene (Cys311-Ser) polymorphism and the presence and extent of CAD. Methods: The study comprised 112 patients recruited from those undergoing coronary angiography for suspected CAD, who were divided according to the presence or absence of CAD into 2 groups Group I including 62 patients with CAD and Group II including 50 patients proved to have normal coronaries. All the subjects included in the study were genotyped for the (Cys311-Ser) polymorphism of PON2 gene using RCR-RFLP. Results: The frequency of Cys allele was significantly higher in group I compared to Group II (77.4% vs. 56% respectively, P < 0.01). Patients with vessel score 3 had significantly higher severity score and higher Cys allele frequency than patients with vessel score 2, the latter group had also significantly higher severity score and Cys allele frequency than patients with vessel score 1. In multivariate logistic regression analysis of different variables for prediction of CAD, age [OR 3.79, CI (1.33 - 12.7), P < 0.01], smoking [OR 0.71, CI (0.23 - 7.81), P < 0.001], and PON2311 Cys allele [OR 5.67, CI (1.99 - 14.77), P < 0.001] were significantly independent predictors of CAD. Conclusion: Cys allele of PON2 311 gene polymorphism is an independent risk factor for CAD and it is associated not only with the presence of CAD but also with its extent and severity.


Mineral chemistry of polymetallic mineralization associated with altered granite, Hangaliya area, South Eastern Desert, Egypt
Mohamed F. Raslan,Mohamed A. Ali
Geologija , 2010,
Abstract: The Hangaliya gold deposit, located in the South Eastern Desert of Egypt, comprises a series of milky quartzveins along NW-trending Hangaliya shear zone, cutting through granitic rocks of Gabal Nugrus monzogranite. Thisshear zone, along with a system of discrete shear and fault zones, formed in the late deformation history of the area.The quartz vein emplacement took place under a brittle-ductile shear regime. Auriferous quartz veins are slightlysheared and boudinaged within the shear zone, especially in the hematized granite. Hydrothermal alteration ispervasive in the granitic wall rocks including sericitization, chloritization, fluoritization, sulphidization and minorcarbonatization. The altered zones and associating quartz veins contain sulphides, gold, silver, cobalt, bismuth, anduraninite minerals.The Hangaliya gold veins include gold, silver, cobaltite, native bismuth, chalcopyrite, pyrite, galena, ferrocolumbite,fergusonite and uraninite. The Au-ore occurs in the quartz veins and adjacent wall rocks as disseminationin chalcopyrite and pyrite. Presence of refractory native silver, bismuth and cobalt in chalcopyrite is inferredfrom microprobe analyses. Wall rock sulphidization also likely contributed to destabilising the gold-silver, cobalt,bismuth assemblages and precipitation of the minerals in the hydrothermal alteration zone adjacent to the quartzveins. Gold occurs in two main modes: “invisible gold” in sulphides and native gold. Most of the “invisible gold”occurs in chalcopyrite and bismuth. The altered granites in the Hangaliya shear zone are enriched in Au, Ag, Bi, Co,and Ni with chalcopyrite, which suggests derivation of these metals from serpentinites due to interaction with thefelsic Nugrus granite.
A New Fast Iterative Blind Deconvolution Algorithm  [PDF]
Mamdouh F. Fahmy, Gamal M. Abdel Raheem, Usama S. Mohamed, Omar F. Fahmy
Journal of Signal and Information Processing (JSIP) , 2012, DOI: 10.4236/jsip.2012.31013
Abstract: Successful blind image deconvolution algorithms require the exact estimation of the Point Spread Function size, PSF. In the absence of any priori information about the imagery system and the true image, this estimation is normally done by trial and error experimentation, until an acceptable restored image quality is obtained. This paper, presents an exact estimation of the PSF size, which yields the optimum restored image quality for both noisy and noiseless images. It is based on evaluating the detail energy of the wave packet decomposition of the blurred image. The minimum detail energies occur at the optimum PSF size. Having accurately estimated the PSF, the paper also proposes a fast double updating algorithm for improving the quality of the restored image. This is achieved by the least squares minimization of a system of linear equations that minimizes some error functions derived from the blurred image. Moreover, a technique is also proposed to improve the sharpness of the deconvolved images, by constrained maximization of some of the detail wavelet packet energies. Simulation results of several examples have verified that the proposed technique manages to yield a sharper image with higher PSNR than classical approaches.
Heavy Metals in Some Fish Species and Bivalves from the Mediterranean Coast of Egypt  [PDF]
Mohamed A. Shreadah, Laila M. Abdel Fattah, Mamdouh A. Fahmy
Journal of Environmental Protection (JEP) , 2015, DOI: 10.4236/jep.2015.61001
Abstract: Biota samples were collected seasonally during three consecutive years from the Egyptian costal region along the Mediterranean Sea for analysis of Zn, Cu, Cd, Pb and Hg. In addition to bivalve Donax, seven commercially important species of fish were examined to provide a comprehensive assessment for the concentrations of these metals in the Mediterranean coastal region of Egypt. Despite of the presence of several land-based sources of contamination, particularly at El-Mex Bay and El-Maadiya, the results showed very weak increase in the concentration of copper, lead and mercury revealing no accumulation of these metals in the biological material, even in non-migrant bivalve species such as Donax. However, an increase in the concentration of zinc and cadmium in fish tissues was measured from 1993 to 1995. Regardless of the fish species, no significant differences were observed in concentrations of most metals between different locations and from season to season. Regarding concentrations of most metals, no interspecies differences could be also measured in either fish tissues or in bivalve Donax. The study indicated that the concentration of these heavy metals were well below the documented toxic levels for human consumption and represent baseline levels against which possible future heavy-metal contamination can be measured.
Paraoxonase 1 gene (Gln192-Arg) polymorphism and the risk of coronary artery disease in type 2 diabetes mellitus  [PDF]
Mohamed Fahmy Elnoamany, Ashraf Abdelraouf Dawood, Rania Mohamed Azmy, Mostafa Mohamed Elnajjar
World Journal of Cardiovascular Diseases (WJCD) , 2012, DOI: 10.4236/wjcd.2012.21006
Abstract: Background: Paraoxonase 1 (PON1) is reported to have an antioxidant and cardioprotective properties. Recently, an association of glutamine (Gln) or (type A)/arginine (Arg) or (type B) polymorphism at position 192 of PON1 gene has been suggested with coronary artery disease (CAD) among patients with diabetes mellitus (DM). However, conflicting results have also been reported. Objectives: To investigate the relationship between PON1 gene (Gln192-Arg) poly-morphism and the presence, extent and severity of CAD in type 2 DM. Methods: The study comprised 180 patients recruited from those undergoing coronary angiography for suspected CAD, who were divided according to the presence or absence of CAD and DM into 4 groups; Group I (n = 40 patients) nondiabetic subjects without CAD, Group II (n = 45 patients) diabetic patients without CAD, Group III (n = 47 patients) non diabetic patients with CAD and Group IV (n = 48 patients) diabetic patients with CAD. PON1 (Gln192-Arg) genotype was assessed using polymerase chain reaction (PCR) followed by AlwI digestion. Results: The frequency of Gln allele (Type A) was significantly higher in group I and group II compared to group III and group IV (62.5%, 60% vs 38.3%, 31.25% respectively, p < 0.001) while the frequency of Arg allele (Type B + Type AB) was significantly higher in ischemic groups (III, IV) compared to non ischemic groups (I,II) (61.7%, 68.75% vs 37.5%, 40% respec-tively, p < 0.001). Patients with CAD and DM (group IV) have significantly higher severity score and vessel score than those with CAD only (group III) (9.7 ± 2.97, 2.44 ± 0.56 vs 6.99 ± 3.71, 1.67 ± 0.89 respectively, p < 0.001) Patients with vessel score 3 had significantly higher severity score and higher Arg allele frequency than patients with vessel score 2, the latter group had also significantly higher severity score and Arg allele frequency than patients with vessel score 1 (8.9 ± 2.79 vs 5.21 ± 2.13 and 80.49% vs 67.86%), (5.21 ± 2.13 vs 3.11 ± 0.89 and 67.86% vs 53.85%), p < 0.001 for all. In multivariate logistic regression analysis of different variables for prediction of CAD, age [OR 2.99, CI (1.11 - 10.5), P < 0.01], smoking [OR 4.13, CI (1.37 - 11.7), P < 0.001], low density lipoprotein (LDL) cholesterol > 100 mg/dL [OR 4.31, CI (1.25 - 12.5), P < 0.001], high density lipoprotein (HDL) cholesterol <40 mg/dL [OR 5.11, CI (1.79 - 16.33), P < 0.001] and PON1 192 Arg allele [OR 4.62, CI (1.67 - 13.57), P < 0.001] were significantly independent predictors of CAD. Conclusion: Arg allele of PON1 192 gene
Applicability of Sigmoid Colon Graft for Vaginal Replacement (Colovaginoplasty) at Young Age  [PDF]
Mohamed A. Baky Fahmy, Hanaa Abdel Hamid M. Al Abeissy, Mohamed M. Abdalla
Surgical Science (SS) , 2011, DOI: 10.4236/ss.2011.28092
Abstract: Objective: - To evaluate the applicability, feasibility, complications, short and long term results of vaginoplasty by using sigmoid colon graft with stapler assistance for resuming colonic continuity in children with absent vagina. Patients and Methods: - Records of 15 patients 8 of them had Androgen Insensitivity Syndrome, 4 had congenital vaginal atresia, and 3 had Congenital Adrenal Hyperplasia, underwent sigmoid graft vaginal reconstruction with the aid of circular stapler during the period from 2005 to 2010 were reviewed retrospectively. Results: A neovagina was constructed in those patients who aged from 3 to 9 years (mean 4 years), where sigmoid colon was used in all patients. Hospital stay ranged from 5 to 12 days (mean 7), operative time ranged from 60 to 120 min (mean 75 min). All patients were followed up 6 monthly in the first year and then yearly, complications occurred in 4 patients: introital stenosis in 2, and another 2 cases had minor wound infection. The need for neovaginal dilation was indicated in 5 out of 15 patients. There was no complications related to bowel anastomosis, No mortality in this group and the cosmetic results were excellent in all cases. Conclusion: Sigmoid colovaginoplasty appears to be applicable for remedy of vaginal atresia at any age. It is associated with a less complication rate, the long term results is satisfactory and it seems a better technique, especially in girls who doesn’t expect sexual activity shortly after surgery.
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