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Search Results: 1 - 10 of 881455 matches for " A. M. S. El Nahrawy "
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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.


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.
On the Real Einstein Beauty E = Kmc2  [PDF]
A. J. Babchin, M. S. El Naschie
World Journal of Condensed Matter Physics (WJCMP) , 2016, DOI: 10.4236/wjcmp.2016.61001
Abstract: The paper suggests that E = mc2 may be open to misinterpretation and that in this form it is not what Einstein advanced first. It is further suggested to return to the slightly less compact formula E = Kmc2 where a < K < 1 which has the merit of accounting for the measured ordinary energy density of the cosmos (K = 1/22) and the conjectured missing dark energy density of the universe (K = 21/22) from the view point of economical notation.
Physical Properties of Nano-Composite Silica-Phosphate Thin Film Prepared by Sol Gel Technique  [PDF]
Amany El Nahrawy, Inas Battisha
New Journal of Glass and Ceramics (NJGC) , 2012, DOI: 10.4236/njgc.2012.21004
Abstract: A series of silica-phosphate nano-composites prepared as a host thin films Physical Properties of Nano-Composite Silica-Phosphate Thin Film Prepared by Sol Gel Technique and doped with different concentrations of Er3+ ions have been synthesized using tetraesoxysilane TEOS, triethylphosphate TEP and erbium nitrate as precursor sources of silica, phosphorus and erbium oxides. The structural properties of pure silica-phosphate thin films and doped with different concentrations of Er3+ ions were studied, using x-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). The morphology of silica-phosphate was characterized by Scanning electron microscope (SEM).
Toluidine Blue O-Gelatin Gel Dosimeter for Radiation Processing  [PDF]
S. M. Gafar, M. A. El-Kelany, M. A. El-Ahdal, S. R. El-Shawadfy
Open Journal of Polymer Chemistry (OJPChem) , 2014, DOI: 10.4236/ojpchem.2014.43007
Abstract:

In this study the spectrophotometric response of the Toluidine Blue O (TBO)-gelatin gel dosimeter irradiated with gamma rays was characterized. Preparation of dyed-gelatin gel takes place in neutral medium; to give eventually gel dosimeter has a sharp absorbance peak at 635 nm that bleaches quantitatively upon irradiation and the colour change can be measured with UV-VIS spectrophotometer. The useful dose range was 1 - 150 Gy. The radiation chemical yield (G-value) of gel dosimeter was calculated and found to increase by increasing concentration of dye. Post-irradiation storage on the response of gel is discussed. The dose response function, radiation sensitivity, and dependences of the response on environmental factors were studied.

Use of the Newly Synthesized Aqueous Polyurethane Acrylate Binders for Printing Cotton and Polyester Fabrics  [PDF]
Mohamed M. El-Molla, Hanan S. El-Sayad, Madiha A. El-Kashouti, Rasha S. El-Khawaga
Advances in Chemical Engineering and Science (ACES) , 2012, DOI: 10.4236/aces.2012.22027
Abstract: The use of the four new synthesized polyurethane acrylate binders in the pigment print paste for screen printing cotton and polyester fabrics and pigment fixation through the polymerization process of the binder by using the thermofixation technique as well as the UV curing technique was studied. The effect of changing time and temperature of thermofixation, and the time of UV curing on the color strength, and prints fastness properties were also studied. The results showed that, the newly synthesized polyurethane acrylate binders could be successfully used for pigment fixation on cotton and polyester using the two fixation techniques and in general their prints possessed better color strength values as compared to those obtained upon using the selected commercial binders.
Ultra-Pro Hernia System for Repair of Primary Complex Inguinal Hernia: Should It Be the Technique of Choice?  [PDF]
Tamer A. El-Bakary, Nizar M. Bouchiba, Mohamed S. El-Akkad, Ahmed S. El-Faki
Surgical Science (SS) , 2017, DOI: 10.4236/ss.2017.82012
Abstract: Purpose: The introduction of light weight three-dimension meshes into the field of inguinal hernia repair showed excellent outcomes. Ultrapro Hernia System (UHS) is one of these three-dimension meshes that allow reinforcing the pre-peritoneal space with minimal fixation. It improves the patient quality of life with rapid resumption of the daily activities. The aim of this study is to evaluate the short-term outcomes of open mesh repair of primary complex inguinal hernia using UHS mesh. Methods: Between November 2013 and November 2015, seventy five male patients with complex primary inguinal hernia were submitted to open inguinal hernia mesh repair using the UHS. Results: The mean age was 46.1 years. Thirty three patients had inguinoscrotal hernias, 14 with Nyhus type IIIA, 22 with Nyhus type IIIB, & 6 patients had strangulated hernias. The mean operative time was 48 minutes. No operative complications were recorded. Post-operatively, the mean VAS scale on 1 day, 1 week, & 1 month was 3.22, 1.2, & 0.3 respectively. The mean duration of oral analgesics use was 2.1 days. None of the patients reported any chronic pain at 12 months post-operatively. Two cases of superficial wound infection were recorded that were treated by oral antibiotics. No recurrence was reported during a mean follow-up period of 26 months. Conclusion: Inguinal hernia repair using UHS is an effective technique that combines the advantages of the anterior and the pre-peritoneal approaches. It improves the patient’s quality of life with minimal recurrence rates. A larger number of patients with longer follow up periods are needed to increase the validity of our results.
The Odd Generalized Exponential Gompertz Distribution  [PDF]
M. A. El-Damcese, Abdelfattah Mustafa, B. S. El-Desouky, M. E. Mustafa
Applied Mathematics (AM) , 2015, DOI: 10.4236/am.2015.614206
Abstract: In this paper we propose a new lifetime model, called the odd generalized exponential gompertz distribution. We obtained some of its mathematical properties. Some structural properties of the new distribution are studied. The method of maximum likelihood is used for estimating the model parameters and the observed Fisher’s information matrix is derived. We illustrate the usefulness of the proposed model by applications to real data.
Accuracy of Fine Needle Aspiration Cytology of Solitary Thyroid Nodules in Tertiary versus Community Hospital  [PDF]
H. M. El Hennawy, H. O. Abu Zaid, Imaad Bin Mujeeb, Eihab A. El Kahlout, El S. M. Bedair
Surgical Science (SS) , 2013, DOI: 10.4236/ss.2013.411096
Abstract:

Background: Fine needle aspiration cytology (FNAC) is considered as the gold standard diagnostic test for the diagnosis of solitary thyroidnodules (STN). Aim: To compare the accuracy of FNAC in diagnosis of thyroid nodules in Al Khor community hospital versus that of tertiary hospital (Hamad General Hospital) in Qatar. Methods: Retrospective, descriptive and comparative study of 320 patients of any age group and both sexes who have thyroid nodules and are subjected to surgical treatment [160 patients from Al Khor community hospital (group A) and 160 patients from Hamad General Hospital (group B)] during the period from May 2005 to Dec 2012. Each group was subdivided into free hand FNAC (done by physicians) and ultrasonography guided FNAC. All samples were prepared in the same histopathology laboratory and interpreted by the same histopathology team. Results: Free hand FNAC in group A and group B achieved a sensitivity of (10% vs. 50%), specificity of 93% in both groups, positive predictive value of (25% vs. 17%), negative predictive value of (82% vs. 98%), and a total accuracy of (82% vs. 94%) respectively, while

Acute Hydrocephalus Revealing Unusual Cerebellar Mass: Dysplastic Cerebellar Gangliocytoma or Lhermitte-Duclos Disease (LDD)  [PDF]
C. Karekezi, M. Boutarbouch, O. Coulibaly, S. Derraz, A. El Ouahabi, A. El Khamlichi
Neuroscience & Medicine (NM) , 2013, DOI: 10.4236/nm.2013.43026
Abstract:

Lhermitte-Duclos disease (LDD) or dysplastic gangliocytoma of the cerebellum is a rare benign lesion of uncertain pathogenesis characterized by overgrowth of cerebellar ganglion cells which replace granular cells and Purkinje cells; this results in gross thickening of the cerebellar folia. It is revealed by symptoms of raised intracranial pressure, cerebellar impairment and obstructive hydrocephalus. We reported the case of a 41-year-old male who presented with symptoms of acute raised intracranial pressure. Brain computed tomography (CT) scan revealed hydrocephalus due to compression of the 4th ventricle by a large non-enhancing left cerebellar mass. Magnetic resonance imaging (MRI) showed a space-occupying lesion within the left cerebellar hemisphere with unusual striation. Radical surgery was retained though the margins with normal cerebellar tissue were not distinct. Clinical complications after gross total or partial removal of Lhermitte-Duclos lesions have been rarely reported in the literature; herein we stress the importance of extreme caution in removing these lesions in cerebellar areas that have no distinct margins between the lesion and normal tissue.

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