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Fabrication and Characterization of Tungsten Heavy Alloys Using Chemical Reduction and Mechanical Alloying Methods

Open Journal of Applied Sciences 2013年第1期3卷 15-27页

作者： zeinab abdel hamid Sayed Farag Moustafa Walid Mohamed Daoush Fatema abdel Mouez Mona Hassan Corrosion Control and Surface Protection Department Central Metallurgical R&D Institute Helwan Cairo Egypt Powder Technology Department Central Metallurgical R&D Institute Helwan Cairo Egypt

A novel reduction technique has been developed to synthesize nano-sized tungsten heavy alloys powders and compared with the same powders processed by mechanical alloying technique. In the first method, nano-sized tungsten heavy alloys powders have been obtained by reduction of precursors obtained by spray drying of several appropriate aqueous solutions, which were made from salts containing tungsten, cobalt, and nickel. By adjusting the stoichiometry of the component of the solutions, it is possible to obtain the desired chemical composition of the tungsten heavy alloys powders. In the second method, highly pure elemental powders of tungsten heavy alloys have been mechanically alloyed in a tumbler ball mill for different milling time. The investigated tungsten heavy alloy powders with the composition (95%W-3.5%Ni-1.5%Fe), (93%W-4.5%Ni-1.0%Fe-1.5%Co), and (90%W-6%Ni-4%Cu) have been prepared using both methods. The prepared powders have been compacted at 70 bar (200 MPa) and sintered in vacuum furnace at 1400℃. Vacuum sintering was carried out to achieve full densification of the produced tungsten heavy alloys. The investigated materials were going to be evaluated the physical and mechanical properties of the sintered parts such as density;electrical conductivity, hardness, and transverse rupture strength. The results reveal that, the grain size of alloys fabricated by chemical reduction technique (53.1 - 63.8 nm) is smaller than that fabricated by mechanical alloying technique (56.4 - 71.4 nm).

关键词： Tungsten Heavy Alloys Mechanical Alloying Chemical Reduction Powder Metallurgy Hardness Transverse Rupture Strength Conductivity

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Fabrication and characterization copper/diamond composites for heat sink application using powder metallurgy

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Natural Science 2011年第11期3卷 936-947页

作者： zeinab abdel hamid Sayed F. Moustafa Fatma A. Morsy Nevien abdel Atty khalifa Fatma abdel Mouez 不详

Copper composites reinforced with diamond particles were fabricated by the powder metallurgical technique. Copper matrix and diamond powders were mixed mechanically, cold com- pacted at 100 bar then sintered at 900?C. The prepared powders and sintered copper/diamond composites were investigated using X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray analysis (SEM/EDS). The effect of diamond contents in the Cu/diamond composite on the different properties of the composite was studied. On fracture surfaces of the Cu/uncoated diamond composites, it was found that there is a very weak bonding between diamonds and pure copper matrix. In order to improve the bonding strength between copper and the reinforcement, diamond particles were electroless coated with NiWB alloy. The results show that coated diamond particles distribute uniformly in copper composite and the interface between diamond particles and Cu matrix is clear and well bonded due to the formation of a thin layer from WB2, Ni3B, and BC2 between Cu and diamond interfaces. The properties of the composites materials using coated powder, such as hardness, transverse rupture strength, thermal conductivity, and coefficient of thermal expansion (CTE) were exhibit greater values than that of the composites using uncoated diamond powder. Additionally, the results reveals that the maximum diamond incorporation was attained at 20 Vf%. Actually, Cu/20 Vf% coated diamond com- posite yields a high thermal conductivity of 430 W/mK along with a low coefficient of thermal expansion (CTE) 6 × 10–6/K.

关键词： Powder Metallurgy Ceramic-Matrix Composites (CMCs) Ceramics Coating Electroless

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A review of concrete bridge surface defect detection based on deep learning

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Optoelectronics Letters 2024年

作者： LIAO Yanna HUANG Chaoyang abdel-hamid Soliman School of Electronic Engineering， Xi'an University of Posts and Telecommunications School of Digital， Technology， Innovation and Business， Staffordshire University

The detection of surface defects in concrete bridges using deep learning is of significant importance for reducing operational risks， saving maintenance costs， and driving the intelligent transformation of bridge defect detection. In contrast to the subjective and inefficient manual visual inspection， deep learning-based algorithms for concrete defect detection exhibit remarkable advantages， emerging as a focal point in recent research. This paper comprehensively analyzes the research progress of deep learning algorithms in the field of surface defect detection in concrete bridges in recent years. It introduces the early detection methods for surface defects in concrete bridges and the development of deep learning. Subsequently， it provides an overview of deep learning-based concrete bridge surface defect detection research from three aspects: image classification， object detection， and semantic segmentation. The paper summarizes the strengths and weaknesses of existing methods and the challenges they face. Additionally， it analyzes and prospects the development trends of surface defect detection in concrete bridges.

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Modulation of oxidative damage and genotoxicity of biosynthesized zinc oxide nanoparticles via supplementation with modified cinnamaldehyde-loaded chitosan nanoparticles in mice

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Food Science and Human Wellness 2024年

作者： Mosaad A.abdel-Wahhab Aziza A.El-Nekeety Asmaa S.Salman zeinab K.Hamza Engy M.Akl Soher E.Aly Wenyi Kang Department of Food Toxicology & Contaminants， National Research Centre Dokki， Cairo， Egypt Genetic and Cytology Department， National Research Centre Dokki， Cairo， Egypt Department of Fats and Oils， National Research Centre Dokki， Cairo， Egypt National R & D Center for Edible Fungus Processing Technology， Henan University Joint International Research Laboratory of Food & Medicine Resource Function Functional Food Engineering Technology Research Center Henan

Synthesis of zinc oxide nanoparticles (Zn-NPs) via green method is an outstanding alternative to conventional/regular methods; however， the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored. This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles (Cin@CSNPs) against oxidative damage and genotoxicity of zinc oxide nanoparticles (ZnO-NPs) in mice. ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L. Cin was extracted from cinnamon essential oil， and was loaded into chitosan nanoparticle (Cin@CSNPs). Both ZnO-NPs， Cin@CSNPs and CSNPs were characterized. The in vitro release of Cin@CSNPs was determined. In the biological study， 6 groups of male Balb/c mice were treated by gavage for 3 weeks as follows， control group， the group received ZnO-NPs (25 mg/kg b.w)， the groups received Cin@CSNPs at low dose (50 mg/kg b.w) or high dose (100 mg/kg b.w)， and the groups received ZnO-NPs plus Cin@CSNPs at the two tested doses. Blood and tissue samples were collected for different biochemical， genetical and histological studies. The particle size of ZnO-NPs， CSNPs， and Cin@CSNPs were (20.78 ± 2.6)， (170.0 ± 3.7)， and (218.23 ± 2.9) nm， and ξ-potential were (32.7 ± 4.6)， (8.32 ± 0.27) and (4.8 ± 0.21)， respectively. ZnO-NPs disturbed the biochemical and oxidative stress indices， AFP， CEA， TNF-α， chromosomal aberrations in somatic and germ cells， and sperm abnormality along with severe pathological changes in the hepatic， renal， and testicular tissues. Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent. Therefore， the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity， and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.

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Hematological Alterations in an Eastern Sudanese Chronic Kidney Disease Patient Population

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Open Journal of Urology 2024年第6期14卷 359-367页

作者： Mohammed Omer Abaker Gibreel Sundus Kamal Ibrahim Wijdan abdel Aziz Hassan Manar Yahia Mahjoub Leyla Mohammed Kheir hamid Hibatellah Majzoub Abbas Nuha Fouzi Mohammed Secretariat of Academic Affairs Port Sudan Ahlia University Port Sudan Sudan Department of Hematology and Immunohematology College of Graduate Studies Port Sudan Ahlia University Port Sudan Sudan

Background: Chronic Kidney Disease (CKD), associated with a slow and progressive loss of kidney function over a period of several years, is an important clinical disaster with an increasing rate of morbidity and mortality especially in the least developed countries. Many hematological parameters are thought to alter dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. Methods: We tried, retrospectively, to evaluate the peripheral blood hematological alterations in a group of patients undergoing hemodialysis in an eastern Sudan dialysis center to add local medical information. Results: Anemia (Low hemoglobin and hematocrit) was detected in 94% of the patients’ group. Mean Erythrocyte count (3.32vs.4.76 (×109/L)), Hemoglobin concentration (9.4vs.13 (g/dl)), Hematocrit (28.7vs.38.7 (L/L)) and platelet count (296 vs. 238 (×109/L)) were significantly lower in the patients’ group than in the control group (P-values Conclusion: Five out of eight studied parameters (Red cell count, hemoglobin, hematocrit, mean cell hemoglobin concentration, and platelets count) have shown a significant alteration in CKD patients. As the complete blood count (CBC) test is the most utilized test in clinical laboratory practice, these alterations may be considered as early indicators for CKD. Furthermore, all patients with CKD must be routinely checked for these alterations.

关键词： Chronic Kidney Disease Chronic Renal Failure Hematological Alterations CBC Eastern Sudan Hemodialysis

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Fabrication and characterization copper/diamond composites for heat sink application using powder metallurgy

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Natural Science（自然科学期刊） 2011年第11期

作者： zeinab abdel hamid Sayed F. Moustafa Fatma A. Morsy Nevien abdel Atty khalifa Fatma abdel Mouez

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Practical approach to linear endoscopic ultrasound examination of the gallbladder

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World Journal of Radiology 2024年第6期16卷 184-195页

作者： Hussein Hassan Okasha Eyad Gadour Hassan Atalla Omar AbdAllah abdel-Hameed Reem Ezzat Ahmed Elsayed Alzamzamy Elsayed Ghoneem Rasha Ahmad Matar zeinab Hassan Bogdan Miutescu Ayman Qawasmi Katarzyna M Pawlak Ahmed Elmeligui Department of Internal Medicine Division of Gastroenterology and HepatologyKasr Al-Aini School of MedicineCairo UniversityCairo 11562Egypt Department of Gastroenterology and Hepatology King Abdulaziz Hospital-National GuardAhsa 31982Saudi Arabia Department of Medicine School of MedicineZamzam University CollegeKhartoum 11113Sudan Department of Internal Medicine Hepatology and Gastroenterology UnitFaculty of MedicineMansoura UniversityMansoura 35516Egypt Department of Internal Medicine Faculty of MedicineAssiut UniversityAssiut 71511Egypt Department of Gastroenterology and Heptology Maadi Armed Forces Medical ComplexMilitary Medical AcademyCairo 11728Egypt Department of Gastroenterology and Advance Endoscopy Sultant Qaboos Comprehensive Cancer Care and Research CentreMuscat 0961Oman Department of Internal Medicine Stockport Hospitals NHS Foundation TrustManchester SK27JEUnited Kingdom Department of Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 300041Romania Advanced Regional Research Centre in Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 30041Romania Department of Gastroenterology Al-Makassed Islamic Charitable Society HospitalCairo 11124Egypt Division of Gastroenterology St.Michael’s HospitalUniversity of TorontoToronto M5B 1W8Canada Department of Gastroenterology Southend University HospitalEssex SS26XTUnited Kingdom

The gallbladder(GB)is a susceptible organ,prone to various pathologies that can be identified using different imaging *** ultrasound(TUS)is typically the initial diagnostic method due to its numerous well-established ***,in cases of uncertainty or when a definitive diagnosis cannot be established,computed tomography(CT)or magnetic resonance imaging may be employed to provide more detailed ***,CT scans may sometimes offer inadequate spatial resolution,which can limit the differentiation of GB lesions,particularly when smaller yet clinically relevant abnormalities are ***,endoscopic ultrasound(EUS)provides higher frequency compared to TUS,superior spatial resolution,and the option for contrast-enhanced harmonic imaging,enabling a more comprehensive ***,EUS can serve as a supplementary tool when conventional imaging methods are *** review will describe the standard EUS examination of the GB,focusing on its endosonographic characteristics in various GB path-ologies.

关键词： Endoscopic ultrasound Linear endoscopic ultrasound Gallbladder anatomy Gallbladder pathologies Therapeutic endoscopic ultrasound

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A convenient one-step preparation of diaminonitrile compounds

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Chinese Chemical Letters 2009年第3期20卷 261-264页

作者： hamid Golchoubian zeinab Ebrahimzadeh Department of Physical-Inorganic Chemistry University of MazandaranP.O.Box 453Babolsar 47416-95447Iran

A new method for preparation of diaminonitrile compounds is reported. In this method primary aliphatic diamine compounds were condensed with two equivalents of benzaldehyde and sodium cyanide in presence of an aqueous solution of sodium hydrogensulfite under mild conditions. This method provides an efficient, convenient and practical method for the syntheses of diaminonitrile compounds and the products are easily isolated. The prepared new compounds were characterized by elemental analysis, IR, NMR spectroscopies and mass spectrometry.

关键词： Strecker reaction Diaminonitdle Synthesis Cyanide One-step preparation Aliphatic diamine

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Formation and Biomimetic Deposition of Bone-like Hydroxyapatite on Wollastonite-gypsum Composites

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Journal of Bionic Engineering 2018年第5期15卷 894-906页

作者： Yaser Greish Nuha Attia abdel-hamid Mourad Department of Chemistry College of Science United Arab Emirates University AI Ain UAE Department of Ceramics National Research Centre Cairo Egypt Department of Mechanical Engineering College of Engineering United Arab Emirates University Al Ain UAE Mechanical Design Department Faculty of Engineering at Mataria Helwan University Cairo Egypt

Bone cements are often used for bone repair and fixation. The main objective of formulating a bone cement is to achieve structure and properties similarity to bone. In addition, bioactivity of a bone cement provides a major advantage that helps achieving better binding and interaction with the surrounding tissues. In the current study, gypsum was used as a matrix for a composite that comprises highly crys- talline prestine and acid-treated wollastonite （CaSiO3） fibers. Composites made by mixing their powder precursors with deionized water at room temperature, were investigated for their composition using X-ray diffraction （XRD） and Thermogravimetric Analysis （TGA）, for their microstructure using Scanning Electron Microscopy （SEM）, for their compressive strengths and modulus of elasticity, and for setting time measurements. In addition, cement composites were evaluated for their preliminary bioactivity in a protein-free Simulated Body Fluid （SBF） for up to 14 days. Results show the improvement of mechanical properties and bioactivity of the composites using acid-treated wollastonite fibers. This was attributed to the formation of hydrated silica layer on the surface of the acid-treated fibers which improved the binding with the gypsum matrix and provided nucleating sites for the deposition of bone-like apatite spherolites from SBF media.

关键词： gypsum wollastonite bone cement biomimetic SBF microstructure

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The effect of time and type of stress moderators on yield and yield components of cotton on conventional and double‑cropping systems under saline conditions

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Journal of Cotton Research 2021年第4期4卷 322-336页

作者： BORZOUYI zeinab ARMIN Mohammad MARVI hamid Department of Agronomy and Plant Breeding Sabzevar BranchIslamic Azad UniversitySabzevarIran

Background:Today,stress moderators are employed to mitigate crop loss due to the adverse effects of environmental *** current research aimed to investigate the impacts of time and stress moderator types on agro-physiological responses of cotton on conventional and double-cropping systems during 2017 and 2018 under saline conditions.A split-plot factorial experiment was carried out in a randomized complete block design with three *** system[conventional(recommended planting date)and double-cropping systems(sowing after harvest of wheat)]were considered as the main plots,and stress moderator type at four levels[water control,2 mmol·L^(-1) Salicylic acid(SA),100 mmol·L^(-1) Glycine betaine(GB),and 100μmol·L^(-1) sodium nitroprusside(SNP)]and application time(flowering and flowering+bolling stages)were regarded as ***:Plant height,reproductive branch number,the number of bolls,10-boll weight,1000-seed weight,biological yield,seed cotton yield,lint yield,chlorophyll a,chlorophyll b,carotenoids,total chlorophyll,sodium,potassium,and proline content were less in double-cropping system comparing with conventional *** with the stress moderators alleviated soil salinity effects on yield,yield components,and biochemical traits of *** spraying led to maximum plant height,branch number,the number of bolls per plant,10-boll weight and seed cotton *** spraying yielded the highest 1000-seed weight,biological yield,lint percentage and lint *** highest chlorophyll a,chlorophyll b,carotenoids,and total chlorophyll content resulted from SNP ***,yield components,and biochemical traits did not respond to the stress moderator types in double-cropping ***,the highest chlorophyll a,carotenoids,proline content,the number of bolls per plant,and seed cotton yield resulted from SNP spraying in conventional *** statistically significant differences were observed between spraying with SNP and SA in

关键词： Cotton Glycine betaine Salicylic acid Salinity Sodium nitroprusside Sowing date

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