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其他元素对Ti或Ti+B细化铝晶粒效果的影响(1)

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轻合金加工技术 1991年第1期19卷 10-15页

作者： Ahmed a.abdel-hamid 张君尧

铝熔体中存在其他元素时,不论是杂质元素还是合金化元素,他们都会对Ti或Ti+B添加剂细化铝晶粒的效果发生影响。有一些元素能提高或改善这种细化效果;而另一些元素则减弱Ti或Ti+B的细化作用,即使细化剂“中毒”。本文评论了很多元素对细... 详细信息

铝熔体中存在其他元素时,不论是杂质元素还是合金化元素,他们都会对Ti或Ti+B添加剂细化铝晶粒的效果发生影响。有一些元素能提高或改善这种细化效果;而另一些元素则减弱Ti或Ti+B的细化作用,即使细化剂“中毒”。本文评论了很多元素对细化效果的影响,论述了对它们的影响作用进行解释的假说。对一些元素例如Zr和Cr的“中毒”作用提出了不同的解释。

关键词：铝铸铁晶粒细化钛硼影响元素

其他元素对Ti或Ti+B细化铝晶粒效果的影响(2)

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轻合金加工技术 1991年第2期19卷 6-12页

作者： Ahmed a.abdel-hamid 张君尧

研究了难熔金属V、Mo、Zr和Ta对常规Al-4％Ti和Al-5％Ti-1％B中间合金细化工业纯铝(99.8％)晶粒效果的影响。每种难熔金属的含量控制在零到0.30％范围内。在添加Al-4％Ti的情况下,熔体中的Ti含量控制在0.15％的水平;在添加Al-5％Ti-1％... 详细信息

研究了难熔金属V、Mo、Zr和Ta对常规Al-4％Ti和Al-5％Ti-1％B中间合金细化工业纯铝(99.8％)晶粒效果的影响。每种难熔金属的含量控制在零到0.30％范围内。在添加Al-4％Ti的情况下,熔体中的Ti含量控制在0.15％的水平;在添加Al-5％Ti-1％B的情况下,将熔体中的Ti含量控制在0.045％的水平。发现V和Mo能提高两种中间合金细化铝晶粒的效果;而Zr则降低它们的效果或使其中毒。Ta含量为0.1％左右时,使中间合金原来的晶粒细化效果减弱至最小,超过这一含量后则使被减弱的晶粒细化效果有所恢复。Al-4％Ti和Al-5％Ti-1％B中间合金原来的晶粒细化效果,分别在Ta含量为0.35％和0.2％左有时得到恢复,Zr和Ta使细化剂中毒的试验结果,可以用形成了替换的金属间化合物来解释。

关键词：铝铸件晶粒细化钛硼影响元素

Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： Ali a.abdel-Aziz Mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

Influence of anodization conditions on deposition of Hydroxyapatite on α/β Ti alloys for Osseointegration: Atomic Force Microscopy Analysis

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Transactions of Nonferrous Metals Society of China 2024年

作者： Rania E.Hammam Engie M.Safwat Soha a.abdel-Gawad Madiha Shoeib Shimaa El-Hadad Faculty of Engineering， Modern University for Technology and Information (MTI) Restorative and Dental Materials Department， National Research Centre Giza Chemistry Department， Faculty of Science， Cairo University Central Metallurgical Research and Development Institute P.O.87

Integrating titanium-based implants with the surrounding bone tissue remains challenging. This study aims to explore the impact of different anodization voltages （20-80V） on the surface topography of two-phase （α/β） Ti alloys and to produce TiO2films with enhanced bone formation abilities. Scanning electron microscopy coupled with energy dispersive spectroscopy （SEM-EDS） and atomic force microscopy （AFM） were applied to investigate the morphological， chemical， and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite （HA） on their surfaces. Results disclosed that the surface roughness of TiO2films formed on Ti-6Al-7Nb alloys was superior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highest yields of HA after immersion in SBF with enhanced HA surface coverage. The developed HA layer had a mean thickness of 128.38 ± 18.13 μm， suggesting its potential use as an orthopedic implantable material due to its promising bone integration and， hence， remarkable stability inside the human body.

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Electrochemical anodization of cast titanium alloys in oxalic acid for biomedical applications

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 13-24页

作者： Engie M.Safwat Soha a.abdel-Gawad Madiha A.Shoeib Shimaa El-Hadad Restorative and Dental Materials Department National Research CentreGiza 12622Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central Metallurgical Research and Development Institute Helwan 11421Egypt

Titanium and its alloys have numerous biomedical applications thanks to the composition and morphology of their oxide *** this study,the colorful oxide films were formed by anodizing cast Ti-6Al-4V and Ti-6Al-7Nb alloys in a 10%oxalic acid solution for 30 s at different voltages(20–80 V)of a direct current power *** force microscopy was used as an accurate tool to measure the surface roughness of thin films on the nanometer *** electron microscopy and X-ray diffraction were performed to analyze surface morphology and phase *** to the results,the produced titanium oxide layer showed high surface roughness,which increased with increasing anodizing *** impact of anodizing voltages on the color and roughness of anodized layers was *** corrosion resistance of the anodized samples was studied in simulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance spectroscopy and the potentiodynamic polarization *** anodized samples for both alloys at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the best compromise between oxide thickness and corrosion ***,findings showed that TiO_(2) films produced on Ti-6Al-7Nb alloys had superior surface roughness properties compared to those of Ti-6Al-4V alloys,making them more appropriate for orthopedic *** the obtained data and the fruitful discussion,it was found that the utilized procedure is simple,low-cost,and ***,anodization in 10%oxalic acid proved a viable alternative for the surface finishing of titanium alloys for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corrosion

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电子医疗数据云服务安全

电子世界 2013年第17期 84-88页

作者： Asmaa S.Radwan Ayman a.abdel-hamid Yasser Hanafy 尹捍东亚历山大大学医学院医学教育系电子学问组亚历山大阿拉伯科技与海运学院计算机与信息技术系重庆市医疗设备质量检测管理所

医疗信息技术的重要性最近几年得到了戏剧性的提升。研究者、开发者以及公司已经开始努力发展手机、网络、桌面以及企业E健康应用。这些发展又提升了E健康应用和健康信息系统(HIS)之间的互通和数据交换的重要性,进而导致了对敏感数据和... 详细信息

医疗信息技术的重要性最近几年得到了戏剧性的提升。研究者、开发者以及公司已经开始努力发展手机、网络、桌面以及企业E健康应用。这些发展又提升了E健康应用和健康信息系统(HIS)之间的互通和数据交换的重要性,进而导致了对敏感数据和数据交换的安全性的担忧。这篇文章强调了基于云计算服务的HISs和E健康应用之间的标准化数据交换机制和互通性。这项服务在包含有大量的病人记录的HISs上提供一个单一的检索电子医疗记录和搜索此类信息的E健康应用的入口。再者,这项研究提出一个统一的安全平台提供给开发者、安全医疗提供者和组织者一个连接框架的渠道去检索和管理医疗记录,以及提供给大量注册者个人一个连接通道到自己的医疗记录(PHR)。此项服务和平台已经在埃及亚历山大大学医学院示范的医生、病人和医院管理者之间进行了定性的评估。评估结果比较乐观,不过原型的实现还需要更多的研究。

关键词： E-健康医院信息系统(HIS) 电子病例(EMR) 个人信息记录(PHR) 云计算互通性 HL7

Calculation of ship motions in steep waves with restoring and Froude-Krylov forces on an adaptive panel mesh with Gauss and analytic integration methods

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Journal of Hydrodynamics 2024年第2期36卷 275-289页

作者： Malwin Wermbter Moustafa.abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of TechnologyHamburgGermany

The impulse response method is a frequently used method to calculate ship seakeeping *** this paper,the restoring and Froude-Krylov calculation is conducted with constant evaluation of panel pressures as well as Gauss quadrature and an analytical *** applied panel grid is coarsened by an adaptive algorithm which is based on a normal vector *** comparison of methods is based on grid convergence studies which are followed by a verification of forces with computational fluid dynamics(CFD)results on the fixed duisburg test case in *** with experimental results in head,oblique and following waves show that all integration methods are *** exact integration is numerically sensitive in some *** quadrature is highly accurate;however,the additional effort is not beneficial since the geometrical accuracy has-stronger influence on the force amplitudes than the integration *** grid coarsening reduces the simulation time and is accurate up to a level,where the panel length comes close the *** added resistance at the investigated Froude number of 0.05 shows higher uncertainty levels,this applies to the results of both the numerical methods and model tests.

关键词： Ship hydrodynamics seakeeping impulse response method added resistance wave loads

Spatiotemporal landscape pattern changes and their effects on land surface temperature in greenbelt with semi-arid climate:A case study of the Erbil City,Iraq

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Journal of Arid Land 2024年第9期16卷 1214-1231页

作者： Suzan ISMAIL hamid MALIKI Department of Architecture College of EngineeringSalahaddin UniversityErbil 44002Iraq

Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape *** alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban *** are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation *** they are regarded as a powerful measure for enhancing urban environmental *** the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both ***,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern *** study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study *** results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study *** Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any ***,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and ***,for BU,only aggregation index metric affected LST,while none of VL metrics had a *** study provides insights for landscape pla

关键词： land use and land cover change landscape pattern land surface temperature greenbelt remote sensing

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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