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Layered Foam/Film Polymer Nanocomposites with Highly Efficient EMI Shielding Properties and Ultralow Reflection

Nano-Micro Letters 2022年第1期14卷 307-324页

作者： Li Ma Mahdi Hamidinejad Biao Zhao Caiyun Liang Chul B.park Department of Mechanical and Industrial Engineering University of Toronto5 King’s College RoadTorontoON M5S 3G8Canada Institute for Manufacturing Department of EngineeringUniversity of CambridgeCambridge CB30FSUK Laboratory of Advanced Materials Department of Materials ScienceCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438People’s Republic of China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhouHenan 450046People’s Republic of China CAS Key Laboratory of High-Performance Synthetic Rubber and Its Composite Materials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022People’s Republic of China

Lightweight,high-efficiency and low reflection electromagnetic interference(EMI)shielding polymer composites are greatly desired for addressing the challenge of ever-increasing electromagnetic *** layered foam/film PVDF nanocomposites with efficient EMI shielding effectiveness and ultralow reflection power were fabricated by physical *** unique layered foam/film structure was composed of PVDF/SiCnw/MXene(Ti_(3)C_(2)Tx)composite foam as absorption layer and highly conductive PVDF/MWCNT/GnPs composite film as a reflection *** foam layer with numerous heterogeneous interfaces developed between the SiC nanowires(SiCnw)and 2D MXene nanosheets imparted superior EM wave attenuation ***,the microcellular structure effectively tuned the impedance matching and prolonged the wave propagating path by internal scattering and multiple ***,the highly conductive PVDF/MWCNT/GnPs composite(~220 S m^(−1))exhibited superior reflectivity(R)of *** tailored structure in the layered foam/film PVDF nanocomposite exhibited an EMI se of 32.6 dB and a low reflection bandwidth of 4 GHz(RseR of 3.1×10^(-4) dB was obtained which corresponds to only 0.0022% reflection *** consequence,this study introduces a feasible approach to develop lightweight,high-efficiency EMI shielding materials with ultralow reflection for emerging applications.

关键词： 2D MXene nanosheets SiC nanowires Layered foam/film polymer nanocomposites Microcellular structure Absorption-dominated EMI shielding

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Low-dose amitriptyline combined with proton pump inhibitor for functional chest pain

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World Journal of Gastroenterology 2013年第30期19卷 4958-4965页

作者： se Woo park Hyuk Lee Hyun Jik Lee Jun Chul park Sung Kwan Shin Sang Kil Lee Yong Chan Lee Ji Eun Kim Department of Internal Medicine Institute of GastroenterologyYonsei University College of Medicine Biostatistics Collaboration Unit Yonsei University College of Medicine

AIM:To investigate the efficacy of amitriptyline with proton pump inhibitor(PPI)for the treatment of functional chest pain(FCP).METHODS:This was a randomized,open-label trial investigating the addition of low dose amitriptyline(10 mg at bedtime)to a conventional dose of rabeprazole(20 mg/d)(group A,n = 20)vs a double-dose of rabeprazole(20 mg twice daily)(group B,n = 20)for patients with FCP whose symptoms were refractory to *** primary efficacy endpoints were assessed by global symptom score assessment and the total number of individuals with > 50% improvement in their symptom ***:The between-group difference in global symptom scores was statistically significant during the last week of treatment(overall mean difference;3.75 ± 0.31 vs 4.35 ± 0.29,the between-group difference;P 50%,whereas only 26.3% of patients in group B had a similar treatment response(70.6% vs 26.3%,P = 0.008).Specifically,patients in group A had a significantly greater improvement in the domains of body pain and general health perception than did patients in group B(52.37 ± 17.00 vs 41.32 ± 12.34,P = 0.031 and 47.95 ± 18.58 vs 31.84 ± 16.84,P = 0.01,respectively).CONCLUSION:Adding amitriptyline to a PPI was more effective than a double-dose of PPI in patients with FCP refractory to a conventional dose of PPI.

关键词： Functional chest pain Proton pump inhibitor Amitriptyline

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Study on Approach for Computer-Aided Design and Machining of General Cylindrical Cam Using Relative Velocity and Inverse Kinematics

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厦门大学学报（自然科学版） 2002年第S1期41卷 205-页

作者： se-Hwan park Byong-Kook Gu Joong-Ho Shin Geun-Jong Yoo Department of Mechanical Design and Manufacturing Changwon National UniversityDepartment of Mechanical Design and Manufacturing Changwon National UniversityDepartment of Mechanical Design and Manufacturing Changwon National UniversityDepartment of Mechanical Design and Manufacturing Changwon National University Changwon South KoreaChangwon South KoreaChangwon South KoreaChangwon South Korea

Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa tic transfer equipments. This paper proposes a new approach for the shape design and manufacturing of the cylindrical cam. The design approach uses the relative velocity concept and the manufacturing approach uses the inverse kinematics concept. For the shape desig n, the contact points between the cam and the follower roller are calculated bas ed on relative velocity of which the direction is on the common tangential line, and then the whole shape of cam is determined from transformation of the coordi nate system. For the manufacturing procedures, the location and the orientation of cutter path can be allocated corresponding to the designed shape data. The in tegral NC code for multi-axis CNC machining center is created using the inverse kinematics concept from the data of the location and the orientation of cutter path. As the advantages of the proposed approach, the machine tool is designed t o having an alternative size in fabricating the general cam, while the tool must be fitted to diameter size of the follower in the conventional approach. Finally, CAD/CAM program, "Cylindrical DAM", is developed on C++ lan guage. This program can perform shape design, manufacturing and kinematics simul ation, which can make integral NC code for multi-axis CNC machining center. The proposed method can be applied easily on fields of industries.

关键词： Cylindrical Cam Mechanism(CCM) shape design rel ative velocity method NC Code Multi-axis CNC machining center inverse kinema tics

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《源．茶》中国香港

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世界建筑导报 2019年第4期34卷 22-23页

作者： pill and pillow 无不详 LAAB Architects STYLO VISION 香港环境保护署

2014年,服务香港四十多年的湾仔码头被停用和拆下。LAAB以循环再生为设计概念,把从湾仔码头回收的近百支防撞木重塑成不同特式的餐椅,将承载半世纪香港回忆的码头木,移徏到它的新家T·CAFé《源?茶》,一个位于T?park《源.区》的轻食餐... 详细信息

2014年,服务香港四十多年的湾仔码头被停用和拆下。LAAB以循环再生为设计概念,把从湾仔码头回收的近百支防撞木重塑成不同特式的餐椅,将承载半世纪香港回忆的码头木,移徏到它的新家T·CAFé《源?茶》,一个位于T?park《源.区》的轻食餐厅。整理木材后, LAAB把那些来不及经历海水侵蚀的、面目较为完整的、做成寛阔的桌面、茶几,以及此起彼伏的木头长椅;把那些千疮百孔的、布满岁月痕迹的,用透明树脂封化它的本质和形态,做成方形立体的小凳子。这些满布瑕疵,久经沧桑的码头木,现以另一种姿态展示它独特的历史价值。

关键词：中国香港茶几设计概念循环再生海水侵蚀透明树脂历史价值码头

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祁连山国家公园酒泉片区多年气候变化对生态结构的影响研究

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中国资源综合利用 2024年第5期42卷 78-81页

作者：董众祥色拥军张帆卢书祥宋智军甘肃盐池湾国家级自然保护区管护中心甘肃酒泉736300 宁夏天昱科技有限公司银川750000

祁连山国家公园位于甘肃省与青海省的交界处,地处青藏高原东北部边缘,自然资源丰富。为了明确祁连山国家公园酒泉片区生态结构变化趋势,结合2006—2021年Landsat卫星影像数据,运用归一化植被指数(Normalized Difference Vegetation Inde... 详细信息

祁连山国家公园位于甘肃省与青海省的交界处,地处青藏高原东北部边缘,自然资源丰富。为了明确祁连山国家公园酒泉片区生态结构变化趋势,结合2006—2021年Landsat卫星影像数据,运用归一化植被指数(Normalized Difference Vegetation Index,NDVI)建立解译样本集,应用eCognition软件与ArcGIS软件人机交互的解译方式,研究冰川与积雪、草地、河流水面、内陆滩涂、裸岩、湖泊水面、沙地和建设用地等地类的变化。同时,结合研究区2006—2021年温度、湿度、降雨量和蒸发量等数据,运用偏最小二乘法建立祁连山国家公园酒泉片区生态结构变化回归模型,结合MATLAB软件定量模拟分析16年间气候变化对区域生态结构的影响,从而更好地推进区域生态文明建设,保护祁连山生物多样性,维护自然生态系统原真性与完整性。

关键词：祁连山国家公园气候变化生态结构归一化植被指数(NDVI) 气象因子生态因子

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祁连山国家公园酒泉片区生长季植被覆盖的时空变化及其与气候因子的相关性研究

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云南师范大学学报（自然科学版） 2024年第5期44卷 74-78页

作者：宋智军董众祥色拥军张帆卢书祥宁夏天昱科技有限公司宁夏银川750000 甘肃盐池湾国家级自然保护区管护中心甘肃酒泉736300

基于空间分辨率为30 m的Landsat5 TM影像、Landsat7 ETM+影像和Landsat8 OLI影像,通过对影像逐像元信息的提取和分析,结合相应的气象资料,运用均值法、斜率分析法、最小二乘法和相关性分析法,研究了2006-2021年祁连山国家公园酒泉片区... 详细信息

基于空间分辨率为30 m的Landsat5 TM影像、Landsat7 ETM+影像和Landsat8 OLI影像,通过对影像逐像元信息的提取和分析,结合相应的气象资料,运用均值法、斜率分析法、最小二乘法和相关性分析法,研究了2006-2021年祁连山国家公园酒泉片区生长季植被覆盖的时空变化及其与气候因子的相关性.结果表明:(1)气温和降水量等气候因子主导了祁连山国家公园酒泉片区植被生长季的归一化植被指数(Normalized Difference Vegetation Index,NDVI)变化趋势;(2)在长时间序列上,2006-2021年祁连山国家公园酒泉片区植被生长季的NDVI年际变化总体上以0.19%/a的速率增加,其空间特征为南北两侧显著增加、中部轻度增加、其他地区基本不变;(3)在短时间序列上2006-2011年和2016-2021年祁连山国家公园酒泉片区植被生长季NDVI年际变化呈减少趋势,而2011-2016年NDVI年际变化呈增加趋势.

关键词：祁连山国家公园酒泉片区植被覆盖时空变化 NDVI 气候因子

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广州城市湿地水质和土壤特征分析

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湿地科学与管理 2024年第3期20卷 71-74,79页

作者：林妍栏林雯张碧媛代色平李智琦广州市市政工程设计研究总院有限公司广东广州510095 广州市林业和园林科学研究院广东广州城市生态系统国家定位观测研究站广东广州510405

通过了解广州不同类型城市湿地的水质和土壤特征,分析主要污染物的来源,为湿地的养护管理和生态修复提供对策。本研究对海珠湿地公园、天河湿地公园、庄头公园和石井净水厂土壤和水质进行取样,采用元素分析、偏相关分析和变异系数等方... 详细信息

通过了解广州不同类型城市湿地的水质和土壤特征,分析主要污染物的来源,为湿地的养护管理和生态修复提供对策。本研究对海珠湿地公园、天河湿地公园、庄头公园和石井净水厂土壤和水质进行取样,采用元素分析、偏相关分析和变异系数等方法探究河流湿地、人工湿地的水质及土壤养分、重金属含量等特征。结果表明:石井净水厂水质总体较好,DO、BOD_(5)、TP、TN含量等各项指标均达国家Ⅲ类水质以上,海珠湿地公园、天河湿地公园和庄头公园TN含量超标,海珠湿地公园和庄头公园TP超标。海珠湿地公园和庄头公园湿地土壤有机质含量达土壤养分一级水平,天河湿地公园达二级水平,石井净水厂有机质含量为五级水平,湿地土壤中有机质与N、P含量显著相关。海珠湿地公园、天河湿地公园、石井净水厂土壤中重金属含量均未超标,庄头公园土壤中Cu、Zn、Cd、Hg含量均超标。因此,需定期对城市湿地水质和土壤开展监测,利用植物修复、土壤改良等技术加以优化和保护,提升城市湿地水质净化、土壤修复和生态景观效果。

关键词：城市湿地水质土壤养分土壤重金属

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Thermoelectric characteristics of nanocomposites made of Hgse and Ag nanoparticles for flexible thermoelectric devices

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Nano Research 2017年第2期10卷 683-689页

作者： Junggwon Yun Kyoungah Cho Yoonbeom park seunggen Yang Jinyong Choi Sangsig Kim Department of Electrical Engineering Korea University 145 Anam-ro Seongbuk-gu Seou1136-70 I Republic of Korea

We synthesized thermoelectric nanocomposites by mixing Hgse nanoparticles （NPs） and Ag NPs in a solution and investigated the thermoelectric properties of the nanocomposite thin films on flexible plastic substrates. The X-ray diffraction patterns and the X-ray photoelectron spectra of the nanocomposites demonstrate that cation-exchange reactions occurred spontaneously in the mixed solution of Hgse and Ag NPs and that the Hgse NPs were completely converted to Ag2se when the Ag NP content was 20 vol.%. The maximum power factor and the thermoelectric figure of merit were obtained as 75 pW/mK2 and 0.043 at 300 K, respectively, when the Ag NP content was 10 vol.%, which is 100 times higher than that of Hgse NP thin films. In addition, the mechanical stability of the thermoelectric nanocomposite film was confirmed through repeated bending tests.

关键词： Hgse Ag25e,nanoparticles,nanocomposite,flexible thermoelectric,seebeck

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Optimization of thermoelectric properties of n-type Bi_2(Te,se)_3 with optimizing ball milling time

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Rare Metals 2018年第4期37卷 351-359页

作者： Ji-Hee Son Min-Wook Oh Bong-seo Kim Su-Dong park Thermoelectric Conversion Research Center Korea Electrotechnology Research Institute Department of Materials Science and Engineering Hanbat National University

The thermoelectric properties at elevated temperature were investigated for n-type Bi2（Te,se）3 which is obtained from ball milling processed powder with various milling times. Electrical properties such as electrical resistivity and seebeck coefficient are clearly dependent on milling time, in which the carrier concentration is attributed to the change of the electrical properties. The concentrations of the defects are also varied with the ball milling time, which is the origin of the carrier concentration variation. Even though finer grain sizes are obtained after the long ball milling time, the temperature dependence of the thermal conductivity is not solely understood with the grain size, whereas the electrical contribution to the thermal conductivity should be also considered. The highest figure of merit value of ZT = 0.83 is achieved at 373 K for the optimized samples, in which ball milling time is 10 h. The obtained ZT value is 48% improvement over that of the 0.5-h sample at 373 K.

关键词： Thermoelectric properties Ball milling Bi2Te3 seebeck coefficient Grain size Thermalconductivity

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Effects of Heat Treatment in N2 and se Atmosphere on the Densification of Nanoparticle Derived Cu(In,Ga)se2 Absorber Layer

Effects of Heat Treatment in N2 and Se Atmosphere on the Den...

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第十五届国际光伏科学与工程大会

作者： Ki-Hyun Kim se-Jin Ahn Young-Gab Chun Byung-Ok park Kyung-Hoon Yoon Solar Cells Research Center Korea Institute of Energy Research 71-2 Jang-dong Yuseong-gu Daejeon 305-343 Korea Dept.of Inorganic Materials Engineering Kyungpook National University 1370 Sankyuk-dong Puk-ku Daegu 702-701 Korea

Spray-deposited Cu(In,Ga)se (CIGS) absorber layers were heat-treated in N and se atmosphere, respectively, in order to get a dense CIGS absorber layer for solar cells application. Heat treatment in N gas was designed to facilitate the growth of CIGS nanoparticle only by thermal energy, while that in se vapor by thermal energy and se induced thermo-chemical effects at the same time. A large number of pores existed in the as-sprayed absorber layer were still remained even after heat-treated in N atmosphere at 500℃for 1 h. On the other hand, heat treatment in se vapor led to the formation of large particles up to 1μm, demonstrating that se vapor seems to play a critical role in the growth of CIGS nanoparticles and hence the densification of nanoparticle derived CIGS layer.

关键词： Solar Cell Cu(InGa)se2 Absorber Nanoparticle Densification

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