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Thin Layer Chromatographic Study of Bauxite and Quantitative Estimation of Co-Existing Al^(3+), Fe^(2+) and Ti^(4+)

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色谱 2005年第5期23卷 555-561页

作者： MOhAMED NAjAR P A jEURKAR j U RAMANA RAO K V jawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 IndiaJawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 IndiaJawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 India

Thin layer chromatography in combination with spectrophotometry and titrimetry has been used to evaluate chromatographic characteristics of bauxite constituents. The retention behaviors of four major constituents (Al 3+ , Fe 2+ , Ti 4+ , Si 4+ ) in bauxite mineral have been examined on plain and modified layers of silica gel G, silica gel h and cellulose with mobile phases containing aqueous sodium chloride, formic acid and hydrochloric acid. Ternary separation of Al-Fe-Ti was achieved on chromatographic plates made of silica gel h. The ph effect and presence of impurity elements in samples, nature of stationary phases on the ternary separation and detection limits of bauxite constituents were studied. Silicon in bauxite was detected on cellulose plates. Quantitative determinations of Al 3+ , Fe 2+ and Ti 4+ on silica gel h impregnated with sodium formate layers were achieved by titrimetry and spectrophotometry.

关键词：铝土矿主成分共存离子 Ti^4+ Al^3+ Fe^2+ 薄层色谱法

helicobacter pylori infection and endocrine disorders:Is there a link?

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World journal of Gastroenterology 2009年第22期15卷 2701-2707页

作者： Konstantinos X Papamichael Garyphallia Papaioannou helen Karga Anastasios Roussos Gerassimos j Mantzaris First Department of Gastroenterology Evaggelismos Hospital B'Department of Endocrinology Alexandra Hospital

helicobacter pylori(h pylori) infection is a leading world-wide infectious disease as it affects more than half of the world population and causes chronic gastritis,peptic ulcer disease and gastric *** infection elicits a chronic cellular inflammatory response in the gastric ***,the effects of this local inflammation may not be confi ned solely to the digestive tract but may spread to involve extraintestinal tissues and/or ***,h pylori infection has been epidemiologically linked to extra-digestive conditions and *** this context,it has been speculated that h pylori infection may be responsible for various endocrine disorders,such as autoimmune thyroid diseases,diabetes mellitus,dyslipidemia,obesity,osteoporosis and primary *** is a review of the relationship between h pylori infection and these endocrine disorders.

关键词： helicobacter pylori hormones Thyroid Osteoporosis Diabetes Dyslipidemia

基于乳腺MR和US预测乳腺癌腋窝淋巴结阳性病人对新辅助化疗的反应

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国际医学放射学杂志 2019年第6期 734-734页

作者： R Kim j.M.Chang hB lee S.h.lee SY Kim E.S.Kim 徐文达 Departments of Radiology and Breast Surgery Seoul National University Hospital

摘要对于新辅助化疗(NAC)后有望达到腋窝淋巴结病理完全缓解(p CR)的病人,不采取腋窝淋巴结(LN)的清扫可以减少并发症。目的应用MR和US技术建立临床模型预测

关键词：淋巴结阳性新辅助化疗乳腺癌 US MR

Vagal Nerve Stimulation May Be a Potentially Beneficial Treatment for Acute Myocardial Ischemia

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麻醉与监护论坛 2010年第5期17卷 332-334页

作者： j. Xiong F. S. Xue Y. j. Yuan Q. Wang S. Li j. h. Liu X. Liao Y. M. Zhang Department of Anesthesiology Plastic Surgery Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100144 China

Myocardial ischcmia reperfusion injury is an inflammatory process which is characterized with augmenting production and release of proinflammatory cytokines. Although ischemia pre-and postconditioniug can protect myocardium against iscbemia reperfusion injury, existence of some limitations restricts their clinical application widely. Vagus nerve stimulation has been identified with ability to inhibit release of proinflammatory cytokines and to provide other benefits to myocardial ischemia reperfusion injury. Moreover, vagus nerve stimulation has been already used clinically in patients with neuropsychiatric disorders and chronic advanced heart failure. Thus we consider that vagus nerve stimulation may be an effective adjunct treatment attenuating myocardial ischemia reperfusion injury prior to hospital arrival or percutaneous coronary intervention.

关键词：麻醉学原理局部麻醉全身麻醉监护

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纳米胶体硅分散体在水性木器漆中的应用

上海涂料 2005年第6期43卷 35-37页

作者：蒋劼 P.h.j.Greenwood 阿克苏诺贝尔集团依卡化学品公司工业特殊品事业部上海200065

简介了纳米胶体硅产品的种类、特性及影响因素,例举了其在水性木器漆中的应用。

关键词：水性木器漆胶体硅应用纳米分散体

Glyphosate-Resistant Giant Ragweed(Ambrosia trifida L.):2,4-D Dose Response and Control with Postemergence herbicides in Soybean

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American journal of Plant Sciences 2013年第9期4卷 1790-1798页

作者： joanna Follings Nader Soltani Darren E.Robinson Francois j.Tardif Mark B.Lawton Peter h.Sikkema University of Guelph Ridgetown Campus RidgetownCanada University of Guelph GuelphCanada Monsanto Canada GuelphCanada

Glyphosate resistant giant ragweed is an increasing problem in glyphosate resistant cropping systems in southwestern Ontario. The postemergence herbicides registered for use in soybean in Ontario do not provide consistent control of glyphosate resistant giant ragweed. There is limited research on the lowest effective rate of 2,4-D for the control of glyphosate resistant giant ragweed. Consequently, the objectives of this study were a) to determine the efficacy of herbicides applied postemergence for the control of glyphosate resistant giant ragweed in glyphosate resistant soybean, and b) to determine the lowest effective rate of 2,4-D for the control of glyphosate-resistant giant ragweed. Ten postemergence herbicide combinations and seven rates of 2,4-D were evaluated in field studies conducted in 2011 and 2012 at six locations confirmed with glyphosate-resistant giant ragweed. The post emergence herbicides evaluated did not provide acceptable/consistent control. Of the herbicides evaluated, glyphosate plus cloransulam-methyl provided 26% to 70% control 8 WAA of glyphosate resistant giant ragweed, which was the best of the herbicides combinations evaluated. The doses of 2,4-D required to reduce giant ragweed shoot dry weight by 50, 80 and 95% were 142, 310 and 1048 g a.e. ha-1, respectively.

关键词： Glyphosate Resistance Multiple herbicide-Resistant Crops Preplant herbicides Postemergence herbicides

质子数Z分别位于Ru之上和之下的A～(100～126)丰中子原子核三轴形变在原子核形状变迁和共存中的重要作用(英文)

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原子核物理评论 2015年第1期32卷 1-23页

作者：罗亦孝 j.h.hamilton j.O.Rasmussen A.V.Ramayya S.Frauendorf 王恩宏 j.K.hwang 王建国李红洁杨韵颐朱胜江刘艳鑫焦长峰梁午阳石跃许甫荣孙扬刘少华 N.T.Brewer I.Y.lee G.M.Ter-Akopian A.V.Daniel Yu.Oganessian M.A.Stoyer R.Donangelo 马文超 Physics Department Vanderbilt University Lawrence Berkeley National Laboratory Department of Chemistry U.C.Berkeley Department of Physics University of Notre Dame Institut für Strahlenphysik FZD-Rossendorf Department of Physics Tsinghua University School of Science Huzhou Teachers College School of Physics Peking University Department of Physics and Astronomy Shanghai Jiao Tong University Institute of Modern Physics Chinese Academy of Sciences Chemistry Department University of Kentucky Physics Division Oak Ridge National Laboratory Flerov Laboratory for Nuclear Reactions JINR Lawrence Livermore National Laboratory Instituto de Fisica Facultad de Ingenieria Physics Department Mississippi State University

基于Ru(Z=44)丰中子同位素中存在最大三轴形变的理论预言和实验证据,综述了近年来Rh(Z=45),Pd(Z=46),Ag(Z=47),Cd(Z=48)(质子数Z位于Ru,Z=44之上)及Zr(Z=40),Nb(Z=41),Mo(Z=42),Tc(Z=43)(质子数Z位于Ru,Z=44之下)的A～(100～126)丰中子同位素中关于三轴形变的形状变迁和形状共存系统性研究的重要进展。252Cf自发裂变瞬发γ射线γ-γ-γ三重符合、特别是新建立的γ-γ-γ-γ四重符合数据的系统观测和研究,在Ru,Pd,Cd和Nb丰中子同位素中显著扩展或首次观测到了一系列能带,为这个核区原子核形状的研究提供了新的、重要的实验数据。联系此前报道的有关进展,使用PES,TRS,PSM,CCCSM和SCTAC理论模型计算拟合新的实验数据,在该核区沿同中素和同位素链,并随自旋和激发能变化各自由度,跟踪原子核形状渐进变化,获得了新的系统性研究成果,显著扩展和深化了人们对原子核形状变迁和形状共存的认知。对于Ru及其上的Rh(Z=45),Pd(Z=46),Ag(Z=47)和Cd(Z=48)丰中子同位素的研究表明:Rh丰中子核具有比最大值稍小的三轴形变,γ=-28°,并在103–106Rh同位素链上鉴别出了手征对称破缺;在三轴形变核112Ru和114Pd(N=68)中发现了三轴原子核的摆动运动,该摆动运动也可能在114Ru(N=70)中存在;观察到了从具有最大三轴形变的110,112Ru中手征破缺到稍小三轴形变的112,114,116Pd中扰动的手征破缺的过渡;在较软的Ag核中观察到了丰富的谱学结构,在104,105Ag中鉴别出了可能的手征对称破缺,在较重的115,117Ag中提出了趋于三轴形变的γ软度;具有小形变的Cd核的能级结构被解释为准粒子耦合、准转动和软三轴形变;最近的库伦激发的研究提供了Z=50,N=82满壳附近122,124,126Cd核中出现核集体性的实验和理论证据;上述研究成果展现出从Ru中的最大三轴形变(γ=-30°,三轴形变极小增益为0.67 Me V),经具有大三轴形变的Rh核(γ=-28°),到Pd核中的稍小、但稳定于中等自旋到高自旋区的三轴形变(γ～-41°,三轴形变极小增益为0.32 Me V),再经Ag核中的γ软度,最后到具有很小形变、但仍出现集体性质、包括软三轴形变的Cd核的过渡。对于Pd核转动带交叉系统性的研究揭示了其第一带交叉(νh11/2)2中子转动顺排的上行γ驱动,和第二带交叉(πg9/2)2质子转动顺排的下行γ驱动效应,成功地解释了114Pd中的三轴摆动运动,并给出了110-118Pd同位素链中理论早已预言、而比早期理论预言更为完整准确的形状渐进变迁和形状共存的图像。根据该核区的系统研究,发现最大三轴形变出现在112Ru,而在相邻的偶Z(Pd)同位素链,三轴形变极小的中心在114Pd,两者均为N=68。上述系统性研究沿相邻的Ru和Pd偶Z同位素链,在N=68同中素中鉴别出最大三轴形变,均比理论预言的108Ru和110Pd多4个中子。在Z值位于Ru(Z=44)之下的Zr(Z=40),Nb(Z=41),Mo(Z=42)and Tc(Z=43)丰中子同位素中,Y和Zr核具有很强的轴对称四极形变,而在较重的Zr同位素中出现了γ自由度;较重的Nb核(A=104～106)基态具有中等程度的软三轴形变和强四极形变,随着自旋和激发能的增加,过渡到接近于轴对称的强四极形变;而较轻的Nb核(A 103)基态均接近轴对称形状;在Nb同位素链上基态由球形到强四极形变的形状突变发生在100Nb(N=59),在100–106Nb同位素链中基态的软三轴形变随中子数增加而增加;在Nb核中还观察到关于软三轴形变的形状共存;Mo核具有大的三轴形变,观察到了γ振动和手征对称破缺;Tc核具有比最大值稍小的三轴形变,γ=-26°,并观察到了手征对称破缺。质子数Z从41到48的A～(100～126)丰中子同位素,特别是Pd和Nb同位素,呈现出关于三轴形变的过渡特征。

关键词：质子数从41到48范围的丰中子核原子核形状变迁和共存长椭球到扁椭球形状变迁三轴形变三轴形变原子核摆动运动原子核手征对称破缺扰动手征态 γ振动能带高自旋态带交叉 γ驱动效应准转动 Z=50和N=82闭壳附近集体性和软三轴形变的出现能级纲图原子核能级自旋/宇称/组态指定位能面(PES) 投影壳模型(PSM) 总Routhian面(TRS) 推转和组态限制壳模型(CCCSM)和壳修正斜轴推转模型(SCTAC)理论计算自发裂变瞬发γ谱学 γ射线三重和四重符合及角关联测量锎-252 Gammasphere多探测器系统

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东亚夏季风的气候北界指标及其年际变化研究

中国科学：地球科学 2018年第1期48卷 93-101页

作者：陈婕黄伟靳立亚陈建徽陈圣乾陈发虎兰州大学资源环境学院西部环境教育部重点实验室兰州730000 成都信息工程大学大气科学学院成都610225 中国科学院青藏高原研究所高寒生态与生物多样性重点实验室北京100101

长时间尺度东亚夏季风北界的时空变化及其物理机制的研究对理解过去、预测未来气候变化有重要意义,但目前主要基于气象定义的各东亚夏季风北界指标与地理环境缺少对应,也很难应用于古气候研究.本文参照全球季风的概念定义,使用CMAP和GPC... 详细信息

长时间尺度东亚夏季风北界的时空变化及其物理机制的研究对理解过去、预测未来气候变化有重要意义,但目前主要基于气象定义的各东亚夏季风北界指标与地理环境缺少对应,也很难应用于古气候研究.本文参照全球季风的概念定义,使用CMAP和GPCP等月分辨率降水资料,结果发现夏季(5~9月)2mm day^(-1)的等降水线(即300mm降水量)变化范围与中国现代土地覆被类型、气候转换带以及潜在自然植被类型的空间分布存在很好的对应关系,也与风场突变位置一致,具有明确的气候-生态-地理界线意义,可作为东亚夏季风的北界指标(称为气候北界指标).该指标刻画的中国气候态(1981~2010年)东亚夏季风北界整体呈东北-西南走向,在中国北方地区从西到东大致沿中国祁连山东段-贺兰山南麓-大青山-大兴安岭西侧一线.东亚夏季风气候北界在1980~2015年间的年际空间波动范围覆盖了甘肃中部、宁夏北部、内蒙古中东部以及东北地区,北可深入到中蒙边界,南可退缩到山东-河南中部一线,围绕气候态北界在200~700km范围内波动,空间波动幅度从西到东逐渐增大,但不同区域随时间的南北波动趋势大体一致.

关键词：东亚夏季风气候北界指标年际变化空间波动

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