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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

Dielectric and Magnetic Properties of Nano-Structure BiFeO3Doped with Different Concentrations of Co Ions Prepared by Sol-Gel Method

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New Journal of Glass and Ceramics 2015年第3期5卷 59-73页

作者： Inas Kamal Batttisha Ibrahim Sayed ahmed Farag Mostafa Kamal mohamed ali ahmed Emad Girgis Fawzi el Desouki Hesham Azmi el Meleegi Fawzi el Desouki National Research Centre (NRC) Solid State Physics Department 33 Bohouth St Dokki Giza Egypt Metal Physics Laboratory Physics Department Faculty of Science Mansoura University Mansoura Egypt Materials Science Lab (1) Physics Department Faculty of Science Cairo University Giza Egypt National Research Centre (NRC) Thin Film Lab Electron Microscope Department 33 Bohouth St Dokki Giza Egypt

BiFe1-xCoxO3 (x = 0, 0.03, 0.05 and 0.1) symbolic as (BFO, BF3CO, BF5CO and BF10CO) in powder form has been prepared by sol-gel technique using ethylenediamine tetraacetic acid (EDTA) as a chelating agent. X-ray diffraction (XRD) and FTIR analysis showed rhombohedra distorted BiFeO3 structure with compressive lattice distortion induced by the Co substitution at Fe sites. The transmission electron microscope (TEM) shows irregular particles. The additive of cobalt oxide has led to grains refining giving the following crystallite sizes of 18 nm for BF5Co. The scanning electron microscope (SEM) study reveals that the samples morphology shows relatively uniform grain size distribution. The dielectric properties of BiFeO3 nano-particles in the frequency range of 1 up to 5 MHz at RT revealed that the A.C. conductivity of the prepared samples reaches its maximum value in BF5CO. By decreasing BiFeO3 particle size as a result of doping with different Co ion concentrations, an enhancement in magnetization and a simultaneous suppression in current leakage occurred. The remnant magnetization Mr of BiFe1-xCoxO3 (x = 0, 0.03, 0.05, 0.1) ceramics significantly enhanced, which provides potential applications in information storage.

关键词： Nano-Structure Multiferroic BiFe1-xCoxO3 (x = 0 0.03 0.05 0.1) XRD FTIR TEM Remnant Magnetization

A New Thioamide Derivative for Separation and Preconcentration of Multi elements in Aquatic Environment by Cloud Point Extraction

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American Journal of Analytical Chemistry 2011年第6期2卷 697-709页

作者： mohamed M. Hassanien ali M. Hassan Wael I. Mortada ahmed A. el-Asmy 不详

2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results.

关键词： Heavy Metals Preconcentration Cloud Point Extraction 2-(Pyridine-2-Yl)-N-P-Chlorohydrazinecarbothioamide

Detecting Accuracy of Three Dimensional Power Doppler (3DPD) Vascular Indices for Prenatal Diagnosis of Morbidly Adherent Placenta in Patients with Placenta Previa

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Open Journal of Obstetrics and Gynecology 2020年第1期10卷 49-64页

作者： ahmed Sherif Abdel-Hamid Maged Mahmoud elshourbagy mohamed Sayed Aly Shahira Zakaria mohamed ali Ghaly Department of Obstetrics and Gynecology Faculty of Medicine Ain-Shams University Cairo Egypt Department of Obstetrics and Gynecology in Shoubra General Hospital Cairo Egypt

Objective:?The study’s objective was to assess the accuracy of using prenatal 3-dimensional power Doppler analysis of vascular placental indices to accurately diagnose morbidly adherent placenta objectively. Background:?Traditionally, 2D ultrasound was used for the diagnosis of a suspected morbidly adherent placenta (MAP) previa. More objective techniques like 3D power Doppler haven’t been well studied. Study Design:?A prospective cohort study?is?designed for women with gestational age between 28 and?32 weeks with suspected placenta previa. Patients were examined by 2D ultrasound which was used in management decisions.?3D Power Doppler’s VI, FI and VFI were measured during the same examination after manual tracing of placenta;data were blinded to obstetricians. Histopathology was performed to confirm MAP. Results: Our results showed that the 3D power Doppler VI ≥ 16 predicted the diagnosis of MAP with 100% sensitivity, 100% specificity which is better than those of 2D ultrasound. While VI > 33.1 measured by 3D Doppler predicted severe MAP with a sensitivity of 73.9% and specificity of 86.4%, which was superior to 2D ultrasound. Conclusion:?In patients with placenta previa, the 3D Doppler’s vascular index accurately predicts MAP. Furthermore, vascular and vascular flow indices of 3D Doppler were more predictive of severe cases of MAP compared to 2D ultrasound.

关键词： 3D Color Doppler 2D Ultrasound Placental Vascular Indices Morbidly Adherent Placenta Placenta Previa

Protective role of Juniperus phoenicea and Cupressus sempervirens against CCl_4

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2010年第6期1卷 123-131页

作者： Sanaa ahmed ali Maha Zaki Rizk Nabawia ali Ibrahim Mohga Shafik Abdallah Hayat mohamed Sharara Magda mohamed Moustafa Department of Theraputical Chemistry National Research Centre Department of Pharmacognosy National Research Centre Department of Chemistry Faculty of Science Helwan University

AIM: To investigate the role of Cupressus sempervirens (C. sempervirens) and Juniperus phoenicea (J. phoe-nicea) extracts as therapeutic effect against CCl4 with biochemical, histopathological evaluations. METHODS: A single intraperitoneal dose of 10% CCl4 in olive oil (1 mL/kg body weight) was administered to a group of female Wister rats, sacrificed after 24 h (as the injury group). The other groups were given CCl4 as de-scribed above and divided as follows: two groups of ten rats each were orally administered either J. phoenicea extract or C. sempervirens extract three times per week for six weeks and a further group administered CCl4 was left for six weeks to allow self-recovery. At the end of experiment, the rats from all groups were sacrificed for sampling and for biochemical and histological analysis. RESULTS: Remarkable disturbances were observed in the levels of all tested parameters. On the other hand,rats injected with the toxic agent and left for one and a half month to self recover showed moderate improve-ments in the studied parameters while, treatment with both medicinal herbal extracts ameliorated the levels of the disturbed biochemical parameters. The group treated with J. phoenicea extract showed a remarkable improvement in comparison to the CCl4 treated group. The C. sempervirens group revealing an even more re-markable effect showing histopathological liver& kidney profiles close to those of the control ***: C. sempervirens and J. phoenicea leaf extracts show a remarkable effect in enhancing liver and kidney functions and may thus be of therapeutic potential in treatment hepatotoxicity and nephrotoxicity.

关键词： Cupressus sempervirens Juniperus phoeni-cea Carbon tetrachloride Hepatotoxicity Nephrotoxicity

Random Attractors for Stochastic Reaction-Diffusion Equations with Distribution Derivatives on Unbounded Domains

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Applied Mathematics 2015年第10期6卷 1790-1807页

作者： Eshag mohamed ahmed ali Dafallah Abdelmajid Ling Xu Qiaozhen Ma College of Mathematics and Statistics Northwest Normal University Lanzhou China

In this paper, we prove the existence of random attractors for a stochastic reaction-diffusion equation with distribution derivatives on unbounded domains. The nonlinearity is dissipative for large values of the state and the stochastic nature of the equation appears spatially distributed temporal white noise. The stochastic reaction-diffusion equation is recast as a continuous random dynamical system and asymptotic compactness for this demonstrated by using uniform estimates far-field values of solutions. The results are new and appear to be optimal.

关键词： Stochastic Reaction-Diffusion Equation Random Attractors Distribution Derivatives Asymptotic Compactness Unbounded Domain

Existence and Upper Semi-Continuity of Random Attractors for Nonclassical Diffusion Equation with Multiplicative Noise on Rⁿ

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Journal of Applied Mathematics and Physics 2022年第12期10卷 3898-3919页

作者： Fadlallah Mustafa Mosa Abdelmajid ali Dafallah Qiaozhen Ma Eshag mohamed ahmed mohamed Y. A. Bakhet Department of Mathematics and Physics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Al-Fulah Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Faculty of Pure and Applied Sciences International University of Africa Khartoum Sudan School of Mathematics University of Juba Juba South Sudan

This paper is concerned with the existence and upper semi-continuity of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity and multiplicative noise in H1(Rn). First, we study the existence and uniqueness of solutions by a noise arising in a continuous random dynamical system and the asymptotic compactness is established by using uniform tail estimate technique, and then the existence of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity. As a motivation of our results, we prove an existence and upper semi-continuity of random attractors with respect to the nonlinearity that enters the system together with the noise.

关键词： Random Attractors Nonclassical Diffusion Equations Asymptotic Compactness Upper Semi-Continuity

Double J Fixation after Craniotomy: Technical Description of a Modification Method for Bone Flap Fixation (Hiederov Method)

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Open Journal of Modern Neurosurgery 2020年第3期10卷 318-324页

作者： Hieder Al-Shami ahmed M. Salah mohamed Fathy Adel ali Al-Ahly Bank Hospital Cairo Egypt Department of Neurosurgery Faculty of Medicine Kasr-Alainy Medical School Cairo Egypt

Background: Fixation of bone flap following craniotomy is usually achieved by synthetic materials. In rural and poor funding areas, innovation for cheap, safe and applicable material is needed. Purpose: The aim is to assess our new innovative technique in bone flap fixation against traditional techniques. Patients and Methods: The study was a prospective randomized controlled study enrolled at Al-Amal Hospital and Al-Ahly Bank Hospital from 2014-2019. Forty-eight patients were randomized in the study. Group A (24 patients) underwent titanium miniplate fixation while group B (24 patients) underwent our new technique. The new technique is double J tunnels performed by craniotome on either side of the bone (flap and skull sides), then a Prolene suture is passed through the shared stem of J’ holes and secured in the wrapped side of J’s holes and tying it tightly. Both techniques were examined against fixation time, rigidity, offset and final judgment postoperatively. Result: There was no statistically significant difference in using both techniques as regard fixation time. Our new technique was not inferior to the traditional one in achieving rigidity (p > 0.05). The final postoperative assessment was as equal as that seen in miniplate fixation. Conclusion: This technique is a simple, easy, cheap and effective method of fixing craniotomy bone flap.

关键词： Craniotomy Bone Flap Fixation Miniplate Fixation

Prostaglandin E1 administration post liver transplantation and renal outcomes:A retrospective single center experience

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World Journal of Transplantation 2024年第4期14卷 101-109页

作者： Vinay Jahagirdar mohamed ahmed Ifrah Fatima Hassam ali Laura Alba John H Helzberg Lee S Cummings Matthew Wilkinson Jameson Forster alisa Likhitsup Department of Internal Medicine Saint Luke’s Health System of Kansas City and the University of Missouri-Kansas CityKansas CityMO 64111United States Department of Gastroenterology and Hepatology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Division of Internal Medicine Department of Gastroenterology and HepatologySaint Luke’s Health System of Kansas City and University of Missouri-Kansas CityKansas CityMO 64111United States Department of Surgery University of Missouri-Kansas City and Transplant SurgerySaint Luke’s Hospital of Kansas CityKansas CityMO 64111United States Department of Gastroenterology and Hepatology University of MichiganAnn ArborMI 48109United States

BACKGROUND Prostaglandin E1(PGE1),or alprostadil,is a potent vasodilator that improves hepatic blood flow and reduces ischemia-reperfusion injury post-liver transplantation(LT).However,the benefits of PGE1 on renal function after LT have not yet been well *** To assess the impact of PGE1 administration on renal function in patients who underwent liver or liver-kidney *** This retrospective study included all patients who underwent liver or liverkidney transplant at our institution from January,2011 to December,*** were classified based on whether they received ***1 was administered post-LT to those with transaminases>1000 U/L in the immediate postoperative ***,post-LT treatments and/or complications,renal function,and survival were *** logistic regression analysis was performed,and a two-tailed P valuealized ratio on post-LT day 1(2±0.74 vs 1.8±0.4,P=0.03),a longer intensive care unit stay(8.1 days±11.8 days vs 3.8 days±4.6 days,P=0.003),more vasopressor use(55.53 hours±111 hours vs 16.33 hours±26.3 hours,P=0.002),and higher immediate postoperative complications(18.6%vs 4.9%,P=0.04).The PGE1 group also had a significantly higher 90-day readmission rate(29.6%vs 13.1%,P=0.02)and lower 1-year liver graft survival(87.5%vs 98.9%,P=0.005).However,30-day readmission(31.6%vs 27.4%,P=0.64),LT complications(hepatic artery thrombosis,biliary complications,rejection of liver graft,cardiomyopathy),1-year patient survival(96.9%vs 97.8%,P=0.77),overall liver graft survival,and overall patient survival were similar between t

关键词： Liver transplantation Alprostadil Protective agents Transplant Prostaglandin E1