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Nano Research 2011年第8期4卷 746-758页

作者： randy Jalem Ryosuke Koike Yong Yang Masanobu Nakayama Masayuki Nogami Department of Materials Science and Engineering Nagoya Institute of Technology Showa Nagoya 466-8555 Japan

Porous and single crystalline platinum （Pt） nanoparticles （NPs） have been successfully synthesized by reduction of H2PtC16.6H20 and then investigated by optical spectroscopy and transmission electron microscopy. H2PtCI6-6H20 was reduced using ethylene glycol in the presence of polyvinylpyrrolidone under highly acidic conditions （pH 〈 1） to form single crystalline Pt particles about 5 nm in size. These particles were then stacked via {100} facets, forming 50-nm length porous nanocubes with a mosaic structure. The porous Pt NPs exhibited excellent catalytic properties for methanol oxidation. In particular, the electrochemical surface area was -63 m2/g, five times higher than that for non-porous Pt NPs prepared using a conventional method. We suggest that the high catalytic activity of porous Pt NPs is due to a combination of the crystalline structure having exposed {100} facets and a porous morphology.

关键词： Platinum porous nanoparticles catalyst methanol oxidation cyclic voltammetry

基于GIS栅格数据的城市河网水质综合评价模型构建

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环境与健康杂志 2015年第1期32卷 54-58,F0003页

作者：朱慧敏陈强王振峰任坤何溶 randy a.dahlgren 张明华温州医科大学水环境应用技术研究所浙南水科学研究院浙江温州325035 美国加州大学戴维斯分校陆地大气与水资源系

目的建立基于GIS栅格数据的城市河网水质综合评价模型。方法该文章利用温瑞塘河流域32个水质监测点2008年至2010年水质监测数据,采用一种基于GIS栅格的指数模型对城市河网水质进行多因子综合评价,并根据GB3838—2002《地表水环境质量标... 详细信息

目的建立基于GIS栅格数据的城市河网水质综合评价模型。方法该文章利用温瑞塘河流域32个水质监测点2008年至2010年水质监测数据,采用一种基于GIS栅格的指数模型对城市河网水质进行多因子综合评价,并根据GB3838—2002《地表水环境质量标准》对评价结果进行水质等级分类。通过对比分类结果与实际情况来探讨该种水质评价方法的评价效果以及栅格指数模型在温瑞塘河的适用性。结果温瑞塘河流域温州市区河网部分水质较差,大部分区域属于劣Ⅴ类水质,水质综合整治仍需加强;氨氮、总磷为温瑞塘河的主要污染物;塘河水质综合污染状况呈现城市重于郊区农村、旧城区重于新城区、支流重于干流的空间分布特征;GIS指数模型在温瑞塘河流域水质评价的结果与实际水质状况高度吻合。结论该方法具有可行性,适用于城市河网水质评价。

关键词：水质评价 GIS指数模型温瑞塘河

Approximation Algorithms for Vertex Happiness

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Journal of the Operations Research Society of China 2019年第3期7卷 429-448页

作者： Yao Xu Yong Chen Peng Zhang randy Goebel Department of Computing Science University of AlbertaEdmontonAB T6G 2E8Canada Department of Mathematics Hangzhou Dianzi UniversityHangzhou 310018China School of Computer Science and Technology Shandong UniversityJinan 250101China

We investigate the maximum happy vertices(MHV)problem and its complement,the minimum unhappy vertices(MUHV)*** order to design better approximation algorithms,we introduce the supermodular and submodular multi-labeling(SUP-ML and SUB-ML)problems and show that MHV and MUHV are special cases of SUP-ML and SUB-ML,respectively,by rewriting the objective functions as set *** convex relaxation on the I ovasz extension,originally presented for the submodular multi-partitioning problem,can be extended for the SUB-ML problem,thereby proving that SUB-ML(SUP-ML,respectively)can be approximated within a factorof2-2/k(2/k,respectively),where k is the number of *** general results imply that MHV and MUHV can also be approximated within factors of 2/k and 2-2/k,respectively,using the same approximation *** the MUHV problem,we also show that it is approximation-equivalent to the hypergraph multiway cut problem;thus,MUHV is Unique Games-hard to achieve a(2-2/k-e)-approximation,for anyε>*** the MHV problem,the 2/k-approximation improves the previous best approximation ratio max{1/k,1/(△+1/g(△)},where△is the maximum vertex degree of the input graph and g(△)=(√△+√△+1)2△>4△*** also show that an existing LP relaxation for MHV is the same as the concave relaxation on the Lovasz extension for SUP-ML;we then prove an upper bound of 2/k on the integrality gap of this LP relaxation,which suggests that the 2/k-approximation is the best possible based on this LP ***,we prove that it is Unique Games-hard to approximate the MHV problem within a factor of S2(log2 k/k).

关键词： Vertex happiness Multi-labeling Submodular/supermodular set function Approximation algorithm Polynomial-time reduction Integrality gap

基于GIS的平原河网走航在线水质监测方法研究

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浙江农业学报 2012年第3期24卷 503-508页

作者：马小雪纪晓亮李军胡昊梅琨 randy dahlgren 商栩张明华温州医学院水域科学与环境生态研究所浙江温州325035 美国加州大学戴维斯分校土壤、大气与水资源系戴维斯CA95616 浙江省农业科学院数字农业研究所浙江杭州310021

针对常规定点水质监测方法无法完整再现水质指标的时空连续分布特征的问题,将船只搭载的水质实时监测设备与GPS同步形成基于GIS数据支撑的走航在线水质监测手段。通过与常规水质监测方法的对比,走航在线水质监测结果的可靠性得到了验证... 详细信息

针对常规定点水质监测方法无法完整再现水质指标的时空连续分布特征的问题,将船只搭载的水质实时监测设备与GPS同步形成基于GIS数据支撑的走航在线水质监测手段。通过与常规水质监测方法的对比,走航在线水质监测结果的可靠性得到了验证。在温瑞塘河河网选择部分河段进行的实地研究结果表明,走航在线水质监测能够较好地实现对较小尺度范围内水质指标空间分布细节的描绘及对分散点源污染的监测,是对常规定点水质监测的有益补充。

关键词：走航连续水质监测 GIS 分散点源污染

HEAT STROKE IN SPORTS:CAUSES,PREVENTION,AND TREATMENT

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中国运动医学杂志 2006年第1期25卷 123-127页

作者： E.randy Eichner Department of Medicine University of Oklahoma Health Sciences Center

KEY POINTS Heat stroke is always a risk in summer sports, espe- cially football and running. Heat stroke is typically caused by a combination of hot environment, strenuous exercise, clothing that limits evaporation of sweat, inadequate adaptation to the heat, too much body fat, and/or lack of fitness. Early recognition and fast treatment of evolving heat stroke can save lives. Preventing heat stroke hinges on acclimation, hydration, pacing, cooling, and vigilance. Heat stroke is a medical emergency. The life - saving adage is： cool first and transport second.

关键词：运动中署原因预防治疗

3D printing of fine-grained aluminum alloys through extrusion-based additive manufacturing:Microstructure and property characterization

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Journal of Materials Science & Technology 2023年第8期139卷 126-136页

作者： Fengchao Liu Pingsha Dong Abdul Sayeed Khan Yuning Zhang randy Cheng Alan Taub Zongyi Ma Department of Naval Architecture and Marine Engineering University of MichiganAnn ArborMI 48109USA Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA Department of Materials Science and Engineering University of MichiganAnn ArborMI 48109USA

Additive manufacturing(AM)has the potential to transform manufacturing by enabling previously un-thinkable products,digital inventory and delivery,and distributed *** we presented an extrusion-based metal AM method(refer to“SoftTouch”depositionin thefiledpatent)thatis suitablefor making the metal feedstock flowable prior to the deposition through dynamic recrystallization induced grain refinement at elevated *** flowable metal was extruded out of the printer head like a paste for building dense metal parts with fine equiaxed grains and wrought mechanical ***-the-shelf metal rods were used as feedstock and the printing process was completed in an open-air environment,avoiding pricy powders and costly inert or vacuum *** resulting multi-layer de-posited 6061 aluminum alloys yield strength and ductility comparable to wrought 6061 aluminum alloys after the same T6 heat *** extrusion-based metal AM method can also be advanced as green manufacturing technologies for fabricating novel alloys and composites,adding novel features to existing parts,repairing damaged metal parts,and welding advanced metals for supporting sustainable manufac-turing,in addition to being developed into a cost-effective manufacturing process for the fabrication of dense metal of complex structural forms.

关键词： Additive friction extrusion deposition Microstructure refinement Solid state additive manufacturing Additive friction stir deposition Friction stir welding

Why use pre-differentiated cells to address complex multi-factorial neurodegenerative diseases?

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Neural Regeneration Research 2021年第7期16卷 1413-1414页

作者： Alex Kopyov Toni L.Uhlendorf randy W.Cohen Celavie Biosciences LLC OxnardCAUSA Department of Biology California State UniversityNorthridgeCAUSA

Past four decades have seen a concerted push to develop regenerative treatments for incurable neurodegenerative diseases such as Parkinson's disease(PD).PD's pathophysiology is primarily characterized by dopamine defi... 详细信息

关键词： diseases degenerative al.

Practical Genetic Algorithms 2nd ed.

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CURRENT COLLOIDAL DISPERSION GELS ARE NOT SUPERIOR TO POLYMER FLOODING

2004年

作者： randy L. Haupt Sue Ellen Haupt

ISBN: (数字)9780471671756

ISBN: (纸本)9780471455653

* This book deals with the fundamentals of genetic algorithms and their applications in a variety of different areas of engineering and science * Most significant update to the second edition is the MATLAB codes that accompany the text * Provides a thorough discussion of hybrid genetic algorithms * Features more examples than first edition

关键词： Genetic algorithms.

来源：畅想之星图书光盘版（南... 评论

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大庆石油地质与开发 2006年第5期25卷 71-80页

作者： Seright randy Han Peihui Wang Dongmei . New Mexico Tech USA Exploration and Development Research Institute of Daqing Oil Field Company Ltd. PetroChina

The suggestion that the colloidal-dispersion-gel (CDG) process is superior to normal polymer flooding is misleading and generally incorrect. Colloidal dispersion gels, in their present state of technological development, should not be advocated as an improvement to, or substitute for, polymer flooding. Gels made from aluminum-citrate crosslinked polyacrylamides can act as conventional gels and provide effective conformance improvement in treating some types of excess water production problems if sound scientific and engineering principles are respected.

关键词： Colloidal-dispersion-gel(CDG) Polymer flooding Controversy

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珊溪水源地净人为氮输入演变及总氮浓度响应

浙江农业科学 2018年第2期59卷 333-337页

作者：刘元元黄宏梅琨陈汉 randy a.dahlgren 温州医科大学浙南水科学研究院浙江温州325035 浙江省流域水环境与健康风险重点实验室浙江温州325035 加州大学戴维斯分校农业与环境科学学院美国戴维斯ca95616

水体氮浓度/通量对流域净人为氮输入(net anthropogenic nitrogen inputs,NANI)的响应非常敏感,但是目前有关水源地氮浓度对NANI的动态响应的研究仍鲜见报道。以浙江省珊溪水源地作为研究对象,以2005—2014年为研究时段,定量分析总氮(TN... 详细信息

水体氮浓度/通量对流域净人为氮输入(net anthropogenic nitrogen inputs,NANI)的响应非常敏感,但是目前有关水源地氮浓度对NANI的动态响应的研究仍鲜见报道。以浙江省珊溪水源地作为研究对象,以2005—2014年为研究时段,定量分析总氮(TN)浓度对流域NANI的动态响应关系。结果表明,珊溪水源地NANI具有增长趋势,10 a间增加了6.7%。NANI多年平均值为85.76 kg·hm^(-2)·a^(-1),是2009年全国平均值的1.7倍。其中,大气沉降氮、化肥施用氮、食物和饲料氮,以及农作物固定氮的平均贡献率分别为40.98%、34.06%、20.25%和4.70%。NANI的空间差异较大,呈现从上游山区向下游增加的趋势,其中瑞安市是该水源地氮污染的关键源区。NANI是TN浓度回归模型的唯一自变量,方差解释率达到55.4%。未来应将降低化肥施用氮、食品和饲料氮输入强度作为主要目标,通过降低流域NANI强度实现水质改善的目标。

关键词：总氮水体污染动态响应回归模型