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Search Results: 1 - 10 of 50735 matches for " Y. Badr "
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Physical Study of Thin Film and Monolithic Nano-Composites [SiO2: 11P2O5: 3 Al2O3: (1.2) Er (1.2, 1.8 and 3) Yb] Prepared by Sol Gel Technique, Planar Waveguide and Co-Operative Up-Conversion  [PDF]
Y. Badr, I. K. Battisha, A. M. S. El Nahrawy, M. Kamal
New Journal of Glass and Ceramics (NJGC) , 2011, DOI: 10.4236/njgc.2011.12012
Abstract: Nano-composite silica-phosphate system (SiO2- P2O5) co-doped with Al2O3 as a host material and prepared by sol gel technique in two forms monolith and thin film using multilayer spin-coating method were activated by Er3+ and Yb3+ ions as in the formula;[SiO2: 11P2O5: 3 Al2O3: (1.2) Er: (1.2, 1.8 and 3) Yb]. The prepared samples have been synthesized using tetra-ethyl-orthosilicate (TEOS) and triethyl-phosphate (TEP) as precursor sources of silica and phospho-rus oxides. The microstructure and crystallinity of the prepared samples will be characterized by using x-ray diffraction (XRD) which, imply that the crystallite sizes of [SiO2: 11P2O5: 3 Al2O3: (1.2) Er: (1.2) Yb] at 500oC for both thin film and monolith forms of the prepared samples were found to be equal to 35 and 33 nm, respectively. The refractive index will be evaluated by measuring the normal transmission and specular reflection of the prepared samples. The photolu-minescence properties have analyzed in the visible wavelength range between 500 and 800 nm as a function of sample composition.
Synthesis and Characterization of Triply Doped Nano-Composite Alumina-Phospho- Silicates SiO2-P2O5-Al2O3 with Er3+, Sm3+ and Yb3+ Ions Prepared by Sol Gel Technique in Two Different Forms Thin Film and Monolith  [PDF]
I. K. Battisha, M. A. Salem, Y. Badr, M. Kamal, A. M. S. El Nahrawy
New Journal of Glass and Ceramics (NJGC) , 2016, DOI: 10.4236/njgc.2016.61001
Abstract: Nano-composite monolith and thin film Alumina-Phospho-Silicates (SiO2-P2O5-Al2O3):Ln (Ln = Sm, Er, Yb) glasses activated by triply doped with three different rare earth ions (REIs) (Er3+:Yb3+:Sm3+) were prepared by modified sol-gel process. The composition of the prepared samples was as follow (SiO2:11P2O5:3Al2O3:1.2Er2O3:(1.2 - 3)Yb2O3:(0.7 - 1.3)Sm2O3). Tetra-ethyl-orthosilicate (TEOS), tri-ethyl-phosphate (TEP), erbium nitrate, ytterbium nitrate and samarium nitrate were used as precursor materials, respectively. The structure of the prepared samples was studied using X-ray diffraction (XRD), which revealed that the crystallite sizes of monolith and thin film samples both sintered at 900℃?at constant Sm3+ concentration at 1.3 mol% (SPAE1.2Y1.8S1.3) have the following values 44 and 31 nm, respectively. Transmission Electron Microscopy (TEM) of the same prepared samples was used to confirm the presence of nano-structure phase. The photo-luminescence study will be evaluated for the prepared.


Computed Tomography Angiography Compared to Catheter Based Angiography in Evaluation of Cerebral Arterial Aneurysm and Arteriovenous Malformation  [PDF]
Sahar M. Badr, Zuber Ahmed, Maway A. Khafaji, Khalid G. H. Alsafi, Hanan Y. Abbas, Saddig D. Jastaniah
Open Journal of Medical Imaging (OJMI) , 2014, DOI: 10.4236/ojmi.2014.43017
Abstract: Both cerebral arterial aneurysm and arteriovenous malformation are cerebrovascular disease, which required immediate diagnosis and urgent treatment. Since the introduction of multislice CT scanners, CT angiography (CTA) has become a powerful tool for imaging the vascular system. The goal of this study is to compare catheter based angiography and CTA in the evaluation of cerebral arterial aneurysm and arteriovenous malformation AVM. A retrospective analysis of 50 patients for exploring the record of patient who underwent both multislice CT angiography (MSCTA) and catheter based angiography before treatment is presented during last one year in the department of Radiology, King Fahd Hospital-Jeddah, Kingdom of Saudi Arabia. The sensitivity of CTA for picking up aneurysm is 86% and the sensitivity of catheter based angiography for picking up aneurysm is 97%. The specificity of CTA for picking up aneurysm is (76%), the false positive cases are (3%) and the false negative cases are 10%. The sensitivity of both CTA and catheter based angiography for picking up arteriovenous malformation is (90%). The specificity of CTA for picking up AVM is (76%), the false positive cases are (10%) and no false negative cases in CTA are found. The sensitivity and specificity of catheter based angiography is 100% in diagnosis and detection of cerebral arterial aneurysm and AVM. The present study concluded that CTA has high sensitivity and specificity in detecting aneurysm and AVM enough to be chosen as the first step. Catheter based angiography, still a gold standard for radiology examination, is the most accurate, sensitive and specific method in diagnosis and detection of cerebral arterial aneurysm and arteriovenous malformation, which can be done as the second step. In addition, catheter based angiography is done for treatment planning, treatment with interventional procedure and for prognosis after treatment.
Acceptance and Adverse Effects of H1N1 Vaccinations Among a Cohort of National Guard Health Care Workers during the 2009 Hajj Season
Gasmelseed Y Ahmed, Hanan H Balkhy, Saleh Bafaqeer, Badr Al-Jasir, Abdulhakeem Althaqafi
BMC Research Notes , 2011, DOI: 10.1186/1756-0500-4-61
Abstract: We conducted a prospective cohort study of National Guard employees during the 1430 (2009) Hajj season. A survey was used as the primary method for data collection. Participants were vaccinated one to two weeks prior to their trip to Mona, and any side effects reported at the time of injection and three weeks post vaccination were recorded.There were 100 male and 26 female participants in the study. In total, 66.7% (n = 84) of the participants were health care workers (HCWs) and 33.3% (n = 42) were non-health care workers (non-HCWs). Less than half of the respondents (46.8%, n = 59) accepted the vaccination. The vaccination acceptance rate was higher among non-HCWs, at a rate of 71.4% (n = 30); HCWs only accepted at a rate of 34.5% (n = 29) (OR 1.103, 95% CI [0.488-2.496]). The most common reason for vaccine refusal was the impression that the disease was not fatal (25.4%, n = 32). Finally, all participants reported pain at the injection site and 18.3% (n = 11) reported swelling. All other side effects were reported in less than 15% of the participants.Despite fears of the new H1N1 vaccine, there was a reasonable rate of vaccine acceptance among our study participants. Early health education may increase the rate of acceptance of the H1N1 vaccine. Furthermore, additional research is needed on long-term adverse effects of the H1N1 vaccine.The Hajj is an annual Muslim pilgrimage that begins on the first day of Dul-Hajja (12th lunar month) and continues for 13 days. The Hajj occurs at the holy city of Mecca in the Kingdom of Saudi Arabia (KSA). The two- to three-million people who gather in the small, confined holy sites of the city come from multiethnic Muslim communities around the world [1-3].The Saudi National Guard is a military and security force that includes several sub-administrations, of which one is the National Guard Health Affairs. This group is charged with providing health care services to National Guard personnel and their dependents. The group also off
Static Security Enhancement and Loss Minimization Using Simulated Annealing
A.Y. Abdelaziz,S. F. Mekhamer,M. A. L. Badr,H. M. Khattab
International Journal of Intelligent Systems and Applications , 2013,
Abstract: This paper presents a developed algorithm for optimal placement of thyristor controlled series capacitors (TCSC’s) for enhancing the power system static security and minimizing the system overall power loss. Placing TCSC’s at selected branches requires analysis of the system behavior under all possible contingencies. A selective procedure to determine the locations and settings of the thyristor controlled series capacitors is presented. The locations are determined by evaluating contingency sensitivity index (CSI) for a given power system branch for a given number of contingencies. This criterion is then used to develop branches prioritizing index in order to rank the system branches possible for placement of the thyristor controlled series capacitors. Optimal settings of TCSC’s are determined by the optimization technique of simulated annealing (SA), where settings are chosen to minimize the overall power system losses. The goal of the developed methodology is to enhance power system static security by alleviating/eliminating overloads on the transmission lines and maintaining the voltages at all load buses within their specified limits through the optimal placement and setting of TCSC’s under single and double line outage network contingencies. The proposed algorithm is examined using different IEEE standard test systems to shown its superiority in enhancing the system static security and minimizing the system losses.
Photocatalytic degradation of methyl red dye
M.A. Mahmoud,A. Poncheri,Y. Badr,M.G. Abd El Wahed
South African Journal of Science , 2010, DOI: 10.4102/sajs.v105i7/8.86
Abstract: Silica nanoparticles (SiO2 NPs) are active in the photocatalytic degradation of methyl red dye (MR). Si2 NPs and Si2 NPs that have been doped with either silver (Ag NPs) and/or gold nanoparticles (Au NPs) were prepared. The particle size and morphology of the catalysts were assessed by transmission electron microscopy (TEM) imaging. The rate of photocatalytic degradation of MR was found to increase from SiO2 NPs, SiO2 NPs coated with both Au NPs and Ag NPs, SiO2 NPs coated with Ag NPs, SiO2 NPs coated with Au NPs, Ag+-doped SiO2 NPs to Au3+-doped SiO2 NPs.
Electrochemical oxidation of sulfide ions on platinum electrodes
Ibrahim Mohamed Ghayad,Faiza M Al Kharafi,Ayman Y Saad,Badr G Ateya
Modern Applied Science , 2010, DOI: 10.5539/mas.v4n3p2
Abstract: This paper treats the electrochemical oxidation of sulfide ions on platinum using cyclic voltametry. An electrolyte of 3.5% NaCl containing sulfide ions was used as the testing medium. The effects of scan rate, concentration of sulfide ions and temperature on the cyclic voltamograms were investigated. Cyclic voltamograms show small currents in the absence of sulfide ions. In the presence of sulfide ions, the magnitude of the anodic currents in the forward sweep is much more than these in the reverse sweep. Cyclic voltamograms show three features appear in the forward sweep at potentials of -0.1, 0.475 and 1.0 V vs Ag/AgCl, respectively. Peaks currents are increased upon the increase of either the scan rate or temperature. These peaks are explained to show the possible formed species and the possible electrochemical oxidation reactions at the electrode surface.
Diagnostic Value of Exhaled Carbon Monoxide as an Early Marker of Exacerbation in Children with Chronic Lung Diseases
Karima A. Abd EL Khalek,Magda Y. EL Seify,Omneya I. Youssef,Mona M. Badr
ISRN Pediatrics , 2012, DOI: 10.5402/2012/859873
Abstract:
Epidemiological Characteristics and Survival Studies of Rhabdomyosarcoma in East Egypt: A Five-Year Multicenter Study
M. A. Badr,Y. A. Al-Tonbary,A. K. Mansour,T. H. Hassan
ISRN Oncology , 2012, DOI: 10.5402/2012/674523
Abstract:
Sequential Spectrophotometric Method for the Simultaneous Determination of Amlodipine, Valsartan, and Hydrochlorothiazide in Coformulated Tablets
Hany W. Darwish,Said A. Hassan,Maissa Y. Salem,Badr A. El-Zeany
International Journal of Spectroscopy , 2013, DOI: 10.1155/2013/273102
Abstract: A new, simple and specific spectrophotometric method was developed and validated in accordance with ICH guidelines for the simultaneous estimation of Amlodipine (AML), Valsartan (VAL), and Hydrochlorothiazide (HCT) in their ternary mixture. In this method three techniques were used, namely, direct spectrophotometry, ratio subtraction, and isoabsorptive point. Amlodipine (AML) was first determined by direct spectrophotometry and then ratio subtraction was applied to remove the AML spectrum from the mixture spectrum. Hydrochlorothiazide (HCT) could then be determined directly without interference from Valsartan (VAL) which could be determined using the isoabsorptive point theory. The calibration curve is linear over the concentration ranges of 4–32, 4–44 and 6–20?μg/mL for AML, VAL, and HCT, respectively. This method was tested by analyzing synthetic mixtures of the above drugs and was successfully applied to commercial pharmaceutical preparation of the drugs, where the standard deviation is <2 in the assay of raw materials and tablets. The method was validated according to the ICH guidelines and accuracy, precision, repeatability, and robustness were found to be within the acceptable limits. 1. Introduction Many analytical methods have been introduced for the analysis of mixtures among which the molecular absorption spectroscopy was the most simple, fast, and applicable in laboratories. Molecular absorption spectroscopy has been extensively used for the determination of drugs in pharmaceutical preparations with a view to the development of analytical methods. The use of this technique for pharmaceutical analyses has the inherent constraint that most active drugs absorb in the UV region and exhibit strongly overlapped spectra that impede their simultaneous determination. Direct spectrophotometry cannot resolve the drugs in their mixtures with impurities or other drugs, so several manipulations were performed to enable resolution of binary and ternary mixtures. Binary mixtures can be determined using different order derivatives [1], methods manipulating ratio spectra [2, 3] or dual wavelength [4–6], and isoabsorptive method [7]. For ternary mixtures, few spectrophotometric methods could resolve the overlap in their spectra, namely, Derivative Ratio Zero Crossing [8] and Double Divisor Ratio Spectra-Derivative Spectrophotometry [9] methods. This paper describes the development and subsequent validation of a novel, simple, and rapid spectrophotometric method “Sequential Spectrophotometry” for simultaneous quantitation of ternary mixtures. The method was
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