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电子心血管数据与流行病学研究现场收集数据的一致性研究

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中华高血压杂志 2017年第8期25卷 799-799页

作者： Ahmad FS Chan C Rosenman MB Post WS Fort DG Greenland P liu kj Kho A Allen NB 刘莉叶鹏

为了评估来自于电子数据研究网络的数据与队列研究中通过标准化研究方法收集的数据的一致程度，芝加哥Feinberg医学院的Ahmad教授及其同事将来自基于社区队列的多种族动脉粥样硬化研究（multi—ethnic study of atherosclerosis，MESA... 详细信息

为了评估来自于电子数据研究网络的数据与队列研究中通过标准化研究方法收集的数据的一致程度，芝加哥Feinberg医学院的Ahmad教授及其同事将来自基于社区队列的多种族动脉粥样硬化研究（multi—ethnic study of atherosclerosis，MESA）的个人数据与HealthLNK联系起来，

关键词：电子数据血管数研究现场流行病学收集一致性动脉粥样硬化队列研究

STABILITY OF MICROSTRUCTURES DURING COOLING PROCESSES OF Al LIQUID METAL

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中国有色金属学会会刊：英文版 1998年第4期8卷 2-7页

作者： liu, RS Li, JY Zhou, Z Dong, kj Peng, P Xie, Q Zheng, CX Hunan Univ Dept Phys Changsha 410012 Peoples R China Hunan Univ Dept Chem Changsha 410012 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｉｓｗｅｌｋｎｏｗｎｔｈａｔｔｈｅｍａｃｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｍｅｔａｌｓａｎｄａｌｏｙｓａｒｅｍａｉｎｌｙｄｅｔｅｒｍｉｎｅｄｂｙｔｈｅｉｒｍｉｃｒｏｓｔｒｕｃｔｕ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｉｓｗｅｌｋｎｏｗｎｔｈａｔｔｈｅｍａｃｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｍｅｔａｌｓａｎｄａｌｏｙｓａｒｅｍａｉｎｌｙｄｅｔｅｒｍｉｎｅｄｂｙｔｈｅｉｒｍｉｃｒｏｓｔｒｕｃｔｕｒｅｓ，ａｎｄｔｈｅｍｉｃｒｏｓｔ...

关键词： stability microstructure liquid metal rapid cooling computer simulation

Nucleation and Oriented Textured Growth of Diamond Films on Si(100) via Electron Emission in Hot Filament Chemical Vapor Deposition

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Journal of Materials Science & Technology 2000年第1期16卷 19-22页

作者： Wang, WL Liao, kj Wang, BB Chongqing Univ Dept Appl Phys Chongqing 400044 Peoples R China

Oriented textured diamond films were obtained on Si(100) substrate via electron emission in hot filament chemical vapor deposition (HFCVD). A de bias voltage relative to the filament was applied to the tungsten electrode between the substrate and the filament. The nucleation and subsequent growth of diamond films were characterized by scanning electron microscopy and Raman spectroscopy. The experimental results showed that the electron emission from the diamond coating on the electrode played a critical role during the nucleation. The maximum value of nucleation density was up to 10(11) cm(-2) on pristine Si surface at emission current of 250 mA. The effect of the electron emission on the reactive gas composition was analyzed by in situ infrared absorption, indicating that the concentration of CH3 and C2H2 near the substrate surface was extremely increased. This may be responsible for the enhanced nucleation by electron emission.

关键词： Diamond films

Treatment of malignant gastric outlet obstruction with endoscopically placed self-expandable metal stents

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World Journal of Gastroenterology 2009年第35期15卷 4365-4371页

作者： Jill kj Gaidos Peter V Draganov Department of Gastroenterology Hepatologyand NutritionUniversity of Florida

Malignant gastroduodenal obstruction can occur in up to 20%of patients with primary pancreatic,gastric or duodenal *** symptoms include nausea,vomiting,abdominal distention,pain and decreased oral intake which can lead to dehydration, malnutrition,and poor quality of *** stent placement has become the primary therapeutic modality because it is safe,minimally invasive,and a cost-effective option for *** can be successfully deployed in the majority of patients. Stent placement appears to lead to a shorter time to symptomatic improvement,shorter time to resumption of an oral diet,and shorter hospital stays as compared with surgical *** of the obstructive symptoms resulting from stent occlusion,due to tumor ingrowth or overgrowth,can be successfully treated with repeat endoscopic stent placement in the majority of the *** endoscopic stenting and surgical bypass are considered palliative treatments and,to date,no improvement in survival with either modality has been demonstrated.A tailored therapeutic approach,taking into consideration patient preferences and involving a multidisciplinary team including the therapeutic endoscopist,surgeon,medical oncologist, radiation therapist,and interventional radiologist, should be considered in all cases.

关键词： Malignant gastric outlet obstruction Endoscopic self-expandable metal stent Palliativetreatment Endoscopy

Asymmetric Meerwein-Ponndorf-Verley reduction catalyzed by a new type of chiral binaphthol-samarium complex

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Chinese Journal of Chemistry 1996年第6期14卷 561-564页

作者： Ding, ZB Cheng, kj Wu, SH FUDAN UNIV DEPT CHEMSHANGHAI 200433PEOPLES R CHINA

A new type of chiral 1,1'-binaphthol(BINOL) derived samarium complex, prepared from (R)- or (S)-BINOL and SmCl3, serves as an enantioselective catalyst for the Meerwein-Ponndorf-Verley (MPV) reduction in the presence of Molecular Sieves 4 Angstrom(MS 4 Angstrom). Moderate enantioselectivity was obtained. Kinetic studies show slight decrease of the enantiomeric excess with the conversion.

关键词： asymmetric synthesis reduction samarium reagent

Progress in regulating electronic structure strategies on Cu-based bimetallic catalysts for CO_(2)reduction reaction

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Advanced Powder Materials

Advanced Powder Materials 2022年第4期1卷 76-87页

作者： Chunyang Yin Qing Li Jun Zheng Yaqiong Ni Huiqiong Wu Anna-Lena kjøniksen Chuntai liu Yongpeng Lei Yi Zhang Hunan Provincial Key Laboratory of Micro&Nano Materials Interface Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha410083China Hanshan Normal University Chaozhou521041GuangdongChina College of Chemistry and Environmental Engineering&College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518071China Faculty of Engineering Østfold University CollegeP.O.Box 7001757HaldenNorway Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou450002China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

To address the ever-increasing CO_(2)concentration problem in the atmospheric air arisen by massive consumption of fossil fuels,electrocatalytic technologies that reduce CO_(2)to generate high value-added products have been gaining increasing ***-based CO_(2)reduction catalysts have attracted widespread attention owing to their capability of generating C1 and C_(2+)***,Cu-based catalysts are highly challenged by their low product ***,Cu-based bimetallic catalysts have been found the unique catalytical activity and selectivity in CO_(2)reduction reactions(CO_(2)RR).The incorporation of other metals can change the electronic circumstance of Cu-based catalysts,promoting the adsorption ability of the intermediate products and consequently leading to high *** this minireview,we intend to summarize recent advances of Cu-based bimetallic catalysts in producing C1 and C_(2+)products,involving designing heterostructure,alloy,defects and surface modification *** pay special attention to the regulation of electronic structure of the composite catalysts,as well as insights into the relationship between electronic property and catalytical performance for Cu-based bimetallic catalysts.

关键词： Cu-based catalyst CO_(2) RRC_(2+)products Electronic structure regulation Intermetallic synergy

The Legacy and Future of Saussurean Semiology in the Study of Art and Visual Communication

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Language and Semiotic Studies 2022年第1期8卷 123-132页

作者： Maja Rudloff Rasmus kjærboe Roskilde University Denmark The Hirschsprung Collection Denmark

The present study discusses how the emergence of semiology has outlined a new trajectory for visual and pictorial ***,we outline how Ferdinand de Saussure’s thoughts on the sign and its relation to visual communication has ***,we interrogate its impact on art history,an already established science of visuality,throughout the 20th and 21st ***,we briefly discuss whether art history’s answer to reading Saussure is a denial or a positive affirmation of political responsibility shared by visual studies in *** study highlights some of the most pertinent parts of the Saussurean legacy for the study of visual communication as a system,and some of the challenges and opportunities this legacy has created.

关键词： visual communication semiology images art art history

Voltage regulation in LV grids by coordinated volt-var control strategies

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Journal of Modern Power Systems and Clean Energy 2014年第4期2卷 319-328页

作者： Miguel JUAMPEREZ Guangya YANG Søren Bækhøj kjÆR Center for Electric Power and Energy Department of Electrical EngineeringTechnical University of DenmarkElektrovej Building 3252800 Kgs.LyngbyDenmark Danfoss Solar Inverters A/S Ulsnæs 16300 Gra°stenDenmark

The increasing penetration level of photovoltaic(PV)power generation in low voltage(LV)networks results in voltage rise issues,particularly at the end of the *** order to mitigate this problem,several strategies,such as grid reinforcement,transformer tap change,demand-side management,active power curtailment,and reactive power optimization methods,show their contribution to voltage support,yet still *** paper proposes a coordinated volt-var control architecture between the LV distribution transformer and solar inverters to optimize the PV power penetration level in a representative LV network in Bornholm Island using a multi-objective genetic *** approach is to increase the reactive power contribution of the inverters closest to the transformer during overvoltage *** standard reactive power control concepts,cosu(P)and Q(U),are simulated and compared in terms of network power losses and voltage level along the *** a practical implementation,a reconfigurable hardware is used for developing a testing platform based on real-time measurements to regulate the reactive power *** proposed testing platform has been developed within *** project,which targets to study the approaches for large PV power integration into the network,without the need of reinforcement.

关键词： Voltage regulation Reactive power optimization Genetic algorithm

Developing a Pedagogy of Education for Sustainable Futures:Experiences and Observations from Danish Preschools

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ECNU Review of Education 2019年第4期2卷 475-496页

作者： Stig Brostrom Thorleif Frøkjær Danish School of Education Aarhus UniversityTuborgvej 164Building D1062400 København NVDenmark University College Copenhagen

Purpose:This article aims to outline an approach to education for sustainability based on play and science ***/Approach/Methods:While deviated from traditional academic articles,this article has combined knowledge drawn from various action research projects and personal observations from a number of preschool ***:The article results in the development of an educational method:a scientific playworld to support emergent science and ***/Value:The constructed educational approach is value-oriented and challenges children to strike a balance between pessimism and optimism in addressing major societal themes.

关键词： Action research play playworld science sustainable development