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Nano Research 2016年第3期9卷 633-643页

作者： Sangbaek Park Hyun-woo Shim Chan woo lee Hee Jo Song Jae-Chan Kim Dong-wan Kim Department of Materials Science and Engineering Seoul National University Seoul 151-744 Republic of Korea School of Civil Environmental and Architectural Engineering Korea University Seou1136-713 Republic of Korea

we report the facile, one-pot synthesis of 3-D urchin-like w18O49 nanostructures （U-wO） via a simple solvothermal approach. An excellent supercapacitive performance was achieved by the U-wO because of its large Brunauer-Emmett- Teller （BET） specific surface area （ca. 123 m2.g-1） and unique morphological and structural features. The U-wO electrodes not only exhibit a high rate-capability with a specific capacitance （Csp） of -235 F·g-1 at a current density of 20 A.g-1, but also superior long-life performance for 1,000 cycles, and even up to 7,000 cycles, showing -176 F·g-1 at a high current density of 40 A.g-1.

关键词： hierarchical structure w18O49 high-power long cycle life supercapacitor

In?uence of Carbon Equivalent Value on the weld Bead Bending Properties of High-Strength Low-Alloy Steel Plates

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Journal of Materials Science & Technology 2017年第4期33卷 321-329页

作者： Ki Hyuk Kim In Jun Moon Ki won Kim Ki Bong Kang Byung Gyu Park Kwang Seok lee R&D Center of Dongkuk Steel Mill Co. Ltd Pohang 790-729 South Korea Korea Institute of Materials Science Implementation Research Division Materials Deformation Department 797 Changwondaero Changwon Gyeongnarn642-831 South Korea

The contribution of chemical compositions in terms of carbon equivalent value（CEV） on impending crack propagation during weld bead bend tests（wBBTs） was studied with five different high-strength lowalloy steel plates that underwent different rolling processes. The test showed that cracks developed at the weld joint, easily passed through the coarse-grain heat-affected zone（CGHAZ）, and finally were arrested within the heat-affected zone（HAZ）. An apparent decrease in the average crack length, which consequently indicated improvement in crack arrestability, was found with decreasing CEV. In addition,the relatively fine microstructure in the HAZ of low-CEV steel plates helped in preventing the crack from further propagation. Special emphasis was placed on the empirical expectation of critical CEV above which wBBT might fail.

关键词： Mechanical characterization Steel welding Fracture Crack arrestability against bending

基于物联网（IoT）的智慧大棚监控系统研究

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基于物联网（IoT）的智慧大棚监控系统研究

作者： NIYIGENA KwIZERA vincent de Paul 兰州理工大学

学位级别：硕士

粮食是人们生活中的必需品。近年来,世界范围内的粮食需求更加彰显了农业部门的重要性。随着农业领域技术的发展,在温室内维持适宜作物生长的气候条件成为可能,大棚作物的产量得以提高。鉴于此,在温室农业中引入和应用物联网技术可以解... 详细信息

粮食是人们生活中的必需品。近年来,世界范围内的粮食需求更加彰显了农业部门的重要性。随着农业领域技术的发展,在温室内维持适宜作物生长的气候条件成为可能,大棚作物的产量得以提高。鉴于此,在温室农业中引入和应用物联网技术可以解决许多问题,同时可以提高作物产量。本文聚焦于物联网(Internet of Things,IoT)系统在温室环境参数实时采集中的应用,提出了基于模糊自校正机制的智能控制方法,以此来调节温室的环境参数。本文的主要研究工作如下:(1)在认识了可用于温室监测系统的各种物联网技术的基础上提出一种模型,该模型基于ESP8266的Node MCU(Node Micro-Controller Unit)将DHT11(Digital Humidity And Temperature)传感器采集到的空气温度和湿度数据发送到云端。首先使用HTTP(Hyper-Text Transfer Protocol)协议将数据发送到Thing Speak云平台,然后使用MQTT(Message Queuing Telemetry Transport)协议将其发送到***。该过程在提出的工作模型中得以完全实现,能够在温室和农户之间进行数据采集和通信。最后进行了MQTT功能测试,测试结果表明消息被成功发布。(2)温室系统是一个具有多个非线性参数的复杂环境,参数变化会影响作物长势。针对这一现象,本文提出了一个基于热力学第一定律和第二定律的动态模型,其中包含了影响温室环境变化的不同参数。所提出的动态模型既代表了温室环境系统,同时也有助于分析和设计高效的温室控制系统。最后,利用MATLABSIMULINK对所建立的大棚温度和湿度的数学模型进行了验证。(3)针对扰动变化过大导致误差变化较大时控制效果变差的问题,提出了一种新的模糊控制器设计方法,设计了一种基于模糊逻辑的智能控制器。该控制器具有自校正特性,它基于自校正的模糊控制方案,通过调节比例因子来减小静态误差,进而提高系统的控制性能。接着,深入讨论了STFLC(自校正模糊逻辑控制系统),并依据实验配置要求对控制器进行了实时仿真,结果表明该控制器结构对动态非线性系统具有良好的控制效果。

关键词：大棚物联网(IoT) MQTT 监控系统自校正模糊逻辑控制

Concomitant therapy achieved the best eradication rate for Helicobacter pylori among various treatment strategies

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world Journal of Gastroenterology 2015年第1期21卷 351-359页

作者： Hyun Jeong lee Jin Il Kim Jin Soo lee Eun Jung Jun Jung-Hwan Oh Dae Young Cheung woo Chul Chung Byung-wook Kim Sung Soo Kim Division of Gastroenterology Department of Internal MedicineCollege of MedicineThe Catholic University of KoreaSeoul 150-713South Korea

AIM: To compare the Helicobacter pylori(***) eradication rate of clarithromycin-based triple therapy,metronidazole-based triple therapy,sequential therapy and concomitant ***: A total of 680 patients infected with *** were divided into 4 groups and each group was treated with a different eradication ***-based triple therapy was applied to the first group [rabeprazole,amoxicillin and clarithromycin(PAC) group: proton pump inhibitor(PPI),amoxicillin,clarithromycin],whereas the second group was treated with metronidazole-based triple therapy [rabeprazole,amoxicillin and metronidazole(PAM) group: PPI,amoxicillin,metronidazole].The third group was treated with rabeprazole and amoxicillin,followed by rabeprazole,clarithromycin and metronidazole(sequential group).The final group was simultaneously treated with rabeprazole,amoxicillin clarithromycin and metronidazole(concomitant therapy group).In the case of a failure to eradicate ***,second-line quadruple and third-line eradication therapies were ***: The per protocol(PP) analysis was performed on 143,139,141 and 143 patients in the PAC,PAM,sequential and concomitant groups,*** excluded patients who did not receive a C13-urea breath test(22,20,23 and 22 patients,respectively) and patients with less than an 80% compliance level(5,11,6 and 5 patients,respectively).The eradication rates were 76.2%(109/143) in the PAC group,84.2%(117/139) in the PAM group,84.4%(119/141) in the sequential group and 94.4%(135/143) in the concomitant group(P = 0.0002).All 14 patients who failed second-line therapy were treated with thirdline eradication *** these 14 patients,6 infections were successfully eradicated with the thirdline *** PP and intention-to-treat analysis showed an eradication rate of 42.9%(6/14).In the PAC group,3 of 4 patients were successfully cured(3/4,75%); 2 of 2 patients in the PAM group(2/2,100%) and 1 of 5 patients in the seque

关键词： Helicobacter pylori Eradication Drug resistance Co

Numerical Simulation of Duct Flow with Fog Droplets

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Journal of Thermal Science 2010年第6期19卷 533-539页

作者： Abhilash Suryan J. K. lee D. S. Kim H. D. Kim Department of Mechanical Engineering Andong National University FMTRC Daejoo Machinery Co.

Evaporative cooling is a widely used air cooling technique. In this method, evaporation of a liquid in the surrounding air cools the air in contact with it. In the current investigation, numerical simulations are carded out to visualize the evaporation and dynamics of tiny water droplets of different diameters in a long air duct. The effect of initial droplet size on the temperature and relative humidity distribution of the air stream in the duct is investigated. Three different initial conditions of air are considered to verify the influence of ambient conditions. Droplet spray patterns are also analyzed to identify the suitable locations for the spray nozzles within the duct. The resuits obtained are displayed in a series of plots to provide a clear understanding of the evaporative cooling process as well as the droplet dynamics within the ducts.

关键词： Evaporative cooling Fog droplet Two-phase flow Relative humidity

Systematic Review of Case Reports on Polygoni Multiflori Radix Induced Liver Injury

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Systematic Review of Case Reports on Polygoni Multiflori Rad...

Microfluidic dual loops reactor for conducting a multistep reaction

第十四届全国中药和天然药物学术研讨会

作者： vincent Kan Fion Ying Dawn Au Hospital Authority

＜正＞Background Polygoni Multiflori Radix（PMR,何首乌）are commonly used Chinese medicines for premature graying,soreness and weakness in the low back and ***,the adverse drug reactions（ADR）concerning PMR induced liver injury have been reported occasionally with unclear *** China,six pCms containing PMR should be prescribed under the

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 239-246页

作者： Si Hyung Jin Jae-Hoon Jung Seong-Geun Jeong Jongmin Kim Tae Jung Park Chang-Soo lee Department of Chemical Engineering Chungnam National University Daejeon 34134 Korea Lotte Chemical R&D Center Daejeon 34110 Korea Department of Chemistry Chung-Ang University Seoul 06974 Korea

Precise control of each individual reaction that constitutes a multistep reaction must be performed to obtain the desired reaction product efficiently. In this work, we present a microfluidic dual loops reactor that enables multistep reaction by integrating two identical loop reactors. Specifically, reactants A and B are synthesized in the first loop reactor and transferred to the second loop reactor to synthesize with reactant C to form the final product. These individual reactions have nano-liter volumes and are carded out in a stepwise manner in each reactor without any cross-contamination issue. To pre- cisely control the mixing efficiency in each loop reactor, we investigate the operating pressure and the operating frequency on the mixing valves for rotary mixing. This microfluidic dual loops reactor is integrated with several valves to realize the fully automated unit operation of a multistep reaction, such as metering the reactants, rotary mixing, transportation, and collecting the product. For proof of concept, CdSeZn nanopartieles are successfully synthesized in a microfluidic dual loops reactor through a fully automated mukistep reaction. Taking all of these features together, this microfluidic dual loops reactor is a general microfluidic screening platform that can synthesize various materials through a multistep reaction.

关键词： microfluidics multistep reaction rotary mixing nanoparticle

Spectroscopic and structural properties of MgAl_2O_4:Nd^(3+) nanopowders and ceramics

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Journal of Rare Earths 2014年第3期32卷 265-268页

作者： K.Lemański P.J.Dereń w.walerczyk w.Strekv R.Boulesteix R.Epherre A.Matre Institute of Low Temperature and Structure Research Polish Academy of Science ul.Okólna 2 50-422 Wroc?aw Poland University of Limoges SPCTS UMR CNRS 7315 12 Rue Atlantis 87068 Limoges Cedex France

The structural and spectroscopic properties of MgAl2O4：1%Nd3＋ spinel nanocrystals and ceramics were measured and ana-lyzed. Ceramics were prepared from the above mentioned spinel nanocrystals and undoped commercial spinel powder, using the spark plasma sintering （SPS） method. Properties of the obtained ceramics strongly depended on the SPS conditions. The samples were not homogeneous and possessed defects and pores. The most transparent ceramics had 60% transparency at 1000 nm.

关键词： SPS spinel spectroscopy neodymium ceramic rare earths

Cultivation of microalgae for biodiesel production:A review on upstream and downstream processing

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Chinese Journal of Chemical Engineering 2018年第1期26卷 17-30页

作者： Xin Bei Tan Man Kee Lam Yoshimitsu Uemura Jun wei Lim Chung Yiin wong Keat Teong lee Chemical Engineering Department Universiti Teknologi PETRONAS Centre for Biofuel and Biochemical Research Universiti Teknologi PETRONAS Fundamental and Applied Science Department Universiti Teknologi PETRONAS School of Chemical Engineering Universiti Sains MalaysiaEngineering Campus

Fluctuating market price of fossil fuel and overwhelming emission of greenhouse gases to the atmosphere have resulted in climate change and have been a global concern in this decade. Hence, biodiesel has become an alternative option to fossil diesel as it is renewable and environmentally friendly. Nevertheless, this alternative fuel that is usually derived from terrestrial oil crops will cause shortage in food supply and deforestation if mass production is realized. In recent years, cultivation of aquatic microorganism(particularly microalgae) to produce biodiesel is considered as a practical solution due to their high growth rate and ability to synthesize large quantity of lipid within their cell. However, the development of energy and cost-efficiency of microalgae cultivation system are the main issues in producing renewable microalgae biodiesel. Of late, wastewater or organic compost has been used as the cultivation medium as it can provide sufficient nutrients to sustain microalgae *** cultivation method and system are vitally important as these factors undoubtedly affect the final microalgae biomass and lipid yield. In this review, the cultivation system of microalgae, nutrients demanded for microalgae production, cell harvesting and drying, microalgae oil extraction, and utilization of microalgae biomass for biodiesel production are introduced and discussed. It is anticipated to convey clearer perspectives in upstream and downstream processes in microalgae-derived biodiesel production.

关键词： Microalgae Cultivation Lipid Biodiesel Harvesting

Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency

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Carbon Energy 2024年第3期6卷 36-52页

作者： Dae-Ho Son Ha Kyung Park Dae-Hwan Kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue Hwang Jaebaek lee Dong-Hwan Jeon Yunae Cho william Jo Taeseon lee JunHo Kim Sang-Hoon Nam Kee-Jeong Yang Division of Energy Technology DGISTDaeguRepublic of Korea Research Center for Thin Film Solar Cells DGISTDaeguRepublic of Korea Department of Physics Ewha Womans UniversitySeoulRepublic of Korea Department of Physics Incheon National UniversityIncheonRepublic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic *** main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and *** overcome this,it is important to understand their electron-hole behavior *** determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber *** elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)*** the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was *** the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was *** improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.

关键词： carrier separation CZTSSe flexible solar cell local current surface potential