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Advances in Mg corrosion and research suggestions

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Journal of Magnesium and Alloys 2013年第3期1卷 177-200页

作者： Andrej Atrens Guang-Ling Song Fuyong Cao Zhiming Shi Patrick k.Bowen The university of Queensland Materials EngineeringBrisbaneQld 4072 Australia bMichigan Technological university Department of Materials Science and EngineeringHoughtonMI49931USA Oak Ridge National Lab Corros Sci&TechnolOak RidgeTN 37831-6156USA

Recent research is summarised with an emphasis on the use of Mg alloys for biodegradable medical *** melt purification using Zr has been shown to provide the opportunity to produce ultra-high-purity Mg alloys,which could lead to stainless ***'s solution may be a good starting model for the study of Mg for biodegradable medical implant applications.A systematic laboratory investigation is needed to elucidate the details of how the corrosion behaviour is controlled by the various constituents of the body *** the evaluation of the Mg corrosion mechanism there is a critical lack of understanding of(i)the amount of hydrogen dissolved in the Mg metal during corrosion,and during anodic polarisation,and(ii)the size film-free area where corrosion occurs,and how to measure this *** the evaluation of the apparent valence of Mg using an applied anodic current density,for reliable values,it is important to apply a sufficiently large applied current *** available data are consistent with the slightly modified uni-positive Mg^(+)ion mechanism,which maintains that(i)the surface of Mg is covered by a partially protective film,and the film-free area increases as the potential becomes more positive(i.e.a catalytic activation process),(ii)corrosion occurs preferentially at breaks in the partial protective film,(iii)corrosion at the breaks in the partially protective film involves the uni-positive Mg ion,(iv)undermining of particles occurs when Mg is severely dissolved,and(v)there may be some self-corrosion not covered by these four processes,which may be associated with crevice-like features on a severely corroded surface or hydride dissolution at relatively negative ***-corrosion might also be possible under condition of essentially uniform ***^(+)has not been experimentally *** existence is postulated as an extremely-short lifetime intermediate in the reaction sequence between metallic Mg and the equilibrium ion Mg^(++).T

关键词： Magnesium Corrosion Stainless Mg uni-positive Mg^(+) Biodegradation Self-corrosion

Wireless Transmission Based Image Quality Analysis Using uni-Level Haar Wavelet Transform

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Circuits and Systems 2016年第8期7卷 1816-1821页

作者： k. Senthamilselvan Lakshmi Dhevi Department of Electronics and Communication Engineering Dhanalakshmi College of Engineering Chennai India Research Scholar Anna University Chennai India

This article deals with picture excellence examination by different parameters utilizing uni-level Haar wavelet transmission in excess of remote channel. The quality is analyzed based on power. The goal is towards reducing absolute power assigned in favour of picture compression and communication, while power in favour of every bit is reserved at prearranged value. Two Power Algorithms were presented. The greatest iterative power control calculation and Minimum Power Adaptation Algorithm (MPAA) are proposed. Those algorithms methodology was utilized for improving the aggregate power dispensed for multimedia such as picture because of input compression and transmission focus towards a settled bit source mutilation. Simulations were performed utilizing Haar wavelet than Additive White Gaussian Ration (AWGN) channel. Different picture excellence parameters, for example, Peak Signal to Noise Ratio (PSNR), M-Normalized Cross-Correla- tion, Average Difference;Structural Content parameters, for example, Maximum Difference, Normalized Absolute Error, Elapsed Time, CPU time, demonstrate a improved presentation with MPAA, Maximum Power Adaptation Algorithms (MAPAA) instead of Conventional Power Adaptation Algorithm (CPAA).

关键词： uni-Level Haar Wavelet Maximum Minimum Additive White Gaussian Ration (AWGN) Minimum Power Adaptation Algorithm (MPAA) Maximum Power Adaptation Algorithms (MAPAA) Conventional Power Adaptation Algorithm (CPAA)

Contrasting habitat use and conservation status of Chinese-wintering and other Eurasian Greater White-fronted Goose(Anser albifrons)populations

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Avian Research 2021年第4期12卷 600-611页

作者： Xueqin Deng Qingshan Zhao Junjian Zhang Andrea kölzsch Diana Solovyeva Inga Bysykatova-Harmey Zhenggang Xu Helmut kruckenberg Lei Cao Anthony David Fox State key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China university of Chinese Academy of Sciences Beijing 101408China Department of Migration Max Planck Institute of Animal BehaviorRadolfzellGermany Institute for Wetlands and Waterbird Research E.V.(IWWR) Verden(Aller)Germany Institute of Biological Problems of the North MagadanRussia Institute of Biological Problems of Cryolitozone YakutskRussia key Laboratory of National Forestry and Grassland Administration On Manage-ment of Western Forest Bio-Disaster College of ForestryNorthwest A&F Uni-versityYangling 712100China Department of Ecoscience Aarhus UniversityAarhusDenmark

Background:GPS/GSM tracking data were used to contrast use of(i)habitats and(ii)protected areas between three Arctic-nesting Greater White-fronted Geese(Anser albifrons,GWFG)populations throughout the annual *** wished to demonstrate that the East Asian Continental Population(which winters on natural wetlands in the Chinese Yangtze River floodplain and is currently declining)avoids using farmland at multiple wintering *** also gath-ered tracking evidence to support general observations from two increasing population of GWFG,the North Sea-Baltic(which winters in Europe)and the West Pacific(which winter in korea and japan)winter mostly within farmland landscapes,using wetlands only for safe night ***:We tracked 156 GWFG throughout their annual cycle using GPS/GSM transmitters from these three popu-lations to determine migration routes and stopover staging *** used Brownian Bridge Movement Models to generate summer,winter and migration stopover home ranges which we then overlaid in GIS with land cover and protected area boundary at national level to determine habitat use and degree of protection from nature conserva-tion designated ***:Data confirmed that 73%of European wintering GWFG homes ranges were from within farmland,com-pared to 59%in japan and korea,but just 5%in China,confirming the heavy winter use of agricultural landscapes by GWFG away from China,and avoidance of farmland at multiple sites within the Yangtze River *** same GWFG used farmland in northeast China in spring and autumn,confirming their experience of exploiting such habi-tats at other stages of their annual *** wintering birds showed the greatest overlap with protected areas of all three populations,showing current levels of site safeguard are failing to protect this ***:Results confirm the need for strategic planning to protect the East Asian Continental GWFG *** the site protection network in place to p

关键词： Farmland feeding Habitat use Migration National nature reserve Protected areas Staging areas

Structural Aspects of Monomeric Platinum Coordination Complexes

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Materials Sciences and Applications 2014年第8期5卷 512-547页

作者： Milan Melník Peter Mikus Department of Pharmaceutical Analysis and Nuclear Pharmacy Faculty of PharmacyComenius University in BratislavaBratislavaSlovak Republic

This review covers structural parameters of almost two thousand monomeric Pt coordination complexes. The Pt is found in the oxidation states zero, +1, +2, +3 and +4, from which oxidation state +2 by far prevails. There is a wide variety of donor atom ligands from uni-, bi-, ter- and tetradentate with over seventeen types of donor atoms, from which by far prevails P and N donor ligands and chlorine atom. The Pt(0) atoms are two-, three- and four-coordinated;Pt(I) and Pt(III) are only four-coordinated, Pt(II) are four- and five-coordinated, and Pt(IV) are five- and six-coor-dinated. About 10% of these complexes exist as isomers. Included are distortion (65%), cis-trans (30%), mixed isomers and ligand isomerism. The structural parameters are discussed in terms of the coordination about the platinum atom, and correlations are drawn between donor atom, bond length and interbond angles with attention to any trans-effect.

关键词： Structure Platinum Monomeric Isomers Trans-Effect

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能量粒子轰击金刚石的计算机模拟

物理学报 2003年第12期52卷 3135-3141页

作者：李荣斌戴永兵胡晓君沈荷生何贤昶上海交通大学金属基复合材料国家重点实验室上海200030

利用Tersoff势和分子动力学方法研究了初始动能为 5 0 0eV的硼粒子注入金刚石的微观行为 .结果表明 :硼注入后产生温度为 5 0 0 0k的热峰 ,其寿命为 0 18ps;同时产生半径为 0 4 5nm局部非晶化区域 ,三重配位原子数占该区域原子数的 7... 详细信息

利用Tersoff势和分子动力学方法研究了初始动能为 5 0 0eV的硼粒子注入金刚石的微观行为 .结果表明 :硼注入后产生温度为 5 0 0 0k的热峰 ,其寿命为 0 18ps;同时产生半径为 0 4 5nm局部非晶化区域 ,三重配位原子数占该区域原子数的 7% .薄膜表层原子向内弛豫 ,近表层原子向外弛豫 ,表面层与近表层原子的间距减少了15 % ,表面层表现为压应力 .硼原子以B 分裂间隙的形式存在于金刚石结构中 .

关键词： Tersoff势分子动力学粒子轰击金刚石硼粒子粒子注入原子弛豫分裂间隙掺杂

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男性高血压发生情况与健康保护因素的关系

中华高血压杂志 2010年第8期18卷 797-797页

作者： Banda ja Clouston k Sui X Hooker SP Lee CD Blair SN 黄晓斌

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钢管混凝土拱桥徐变影响分析

铁道学报 2011年第3期33卷 100-107页

作者：李生勇李凤芹陈宝春 k M SHRESTHA 福州大学土木工程学院福建福州350108 铁道第三勘察设计院集团有限公司桥梁设计处天津300142

基于龄期调整有效模量法推导出钢管混凝土轴心受压构件徐变系数公式,采用该公式对钢管混凝土轴心受压构件进行徐变分析。由徐变预测结果与试验数据比较可知,在CEB-FIP 78、CEB-FIP 90及ACI 209R等3种典型徐变系数模式中,ACI 209R模式较... 详细信息

基于龄期调整有效模量法推导出钢管混凝土轴心受压构件徐变系数公式,采用该公式对钢管混凝土轴心受压构件进行徐变分析。由徐变预测结果与试验数据比较可知,在CEB-FIP 78、CEB-FIP 90及ACI 209R等3种典型徐变系数模式中,ACI 209R模式较其它两种徐变系数模式更为合理。采用ACI 209R徐变系数模式对1座跨径380 m的大跨钢管混凝土铁路拱桥进行徐变分析,并与CEB-FIP 78模式计算结果进行比较,结论可为其它钢管混凝土拱桥的徐变分析提供参考。

关键词：钢管混凝土徐变轴心受压构件拱桥龄期调整有效模量法徐变系数模式

环境铅暴露与血压的关系:2003-2010美国健康和营养调查

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中华高血压杂志 2014年第10期22卷 999-999页

作者： Hara A Thijs L Asayama k Gu YM jacobs L Zhang ZY Liu YP Nawrot TS Staessen ja 刘莉叶鹏

在铅暴露逐渐降低的环境下,该文通过分析2003-2010美国健康和营养调查资料,旨在研究血铅与血压、高血压的关系。纳入研究对象12 725人,其中非洲裔21.1%,西语裔20.5%,白人58.4%,女性48.7%。与非非洲裔比较,非洲裔的血压[126.5/71.9比123.... 详细信息

在铅暴露逐渐降低的环境下,该文通过分析2003-2010美国健康和营养调查资料,旨在研究血铅与血压、高血压的关系。纳入研究对象12 725人,其中非洲裔21.1%,西语裔20.5%,白人58.4%,女性48.7%。与非非洲裔比较,非洲裔的血压[126.5/71.9比123.9/69.6mm Hg（1mm Hg=0.

关键词：环境铅暴露营养调查高血压健康美国调查资料非洲

High-quality single-crystal CdSe nanoribbons and their optical properties

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Optoelectronics Letters 2008年第3期4卷 161-164页

作者： HOU D.D LIU Y. k ZAPIEN J. A SHAN Y. Y LEE S. T Department of Physics Yunnan Normal University Kunming 650092 China Center of Super-Diamond and Advanced Films （COSDAF） and Department of Physics and Material Science City University of Hong Kong Hong Kong SAR China

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method,in which two-step-thermal-evaporation is used to control CdSe sources' evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width,50 nm in thickness,and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photoluminescence indicates that the lasing emission at 710 nm has been observed under optical pumping(266 nm) at power densities of 25-153 kW/cm2. The full width half maximum(FWHM) of the lasing mode is 0.67

关键词：晶体纳米材料光学性能物理性能