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Journal of Thermal Science 2021年第1期30卷 191-200页

作者： YANG zheng CHENG Xu zheng xinghua CHEN Haisheng Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China Institute for Applied Thermofluidics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany

Supercritical fluid has been widely applied in many industrial *** traditional Reynolds-averaged Navier-Stokes(RANS)equations are directly applied for turbulent flow and heat transfer of the supercritical fluid,ignoring turbulent effect of the thermal physical properties due to the intense *** paper deduces a set of Reynolds-averaged Navier-Stokes equations for supercritical fluid(SCF-RANS equations)to depict turbulent flow and heat transfer of the supercritical fluid taking all the physical parameters as *** SCF-RANS equations include many new correlation terms due to fluctuation of the thermal physical *** methods for the new correlation term have been discussed for closing the SCF-RANS *** of them have relatively mature models,while others are completely new and need profound physical theoretical analysis for proposing reasonable *** paper provides referable information for these new correlations as far as authors *** SCF-RANS equations not only provide the formulation special for flow and heat transfer of the supercritical fluid,but also represent the most sophisticate form of the RANS equations,for every involved physical property has been considered as variable without any simplification.

关键词： SCF-RANS equations supercritical fluid turbulence Reynolds-averaged Navier-Stokes equations

Study on the Heat Conduction of Phase-Change Material Microcapsules

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Journal of Thermal Science 2013年第3期22卷 257-260页

作者： Gangtao Zhao Xiaohui Xu Lin Qiu xinghua zheng Dawei Tang Dept. of Pharmacology General Hospital of Beijing Military Command Chinese People's Liberation Army CN 95824 Troop of Chinese People's Liberation Army CN Institute of Engineering Thermophysics Chinese Academy of Sciences

The 3ω approach was used to measure the effective thermal conductivity of phase-change material microcapsules (PCMMs) based on urea formaldehyde and sliced paraffin. The effective thermal conductivities of PCMMs with different densities were measured within the phase-change temperature range. The relationships between effective thermal conductivity, density and temperature were analysed. The effective thermal conductivity reached peak values within the phase-change temperature range and the temperature peak value was consistent with the peak value of the phase-change temperature. The effective thermal conductivity increased with increasing density due to the decreased porosity of samples and their increased solid-phase conduction.

关键词： 3ω-method, Effective thermal conductivity, Phase-change material microcapsules

Piezoelectric Properties of(Na0.5K0.5-xLix)NbO3 Ceramics

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Journal of Materials Science & Technology 2007年第6期23卷 833-836页

作者： Peng QI Jinfeng WANG Baoquan MING Juan DU xinghua LIANG Limei zheng School of Physics Shandong University Jinan 250100 China

Lead-free piezoelectric ceramics （Na0.5K0.5-xLix）NbO3 （x=0.057-0.066） were synthesized by an ordinary sin-tering technique. Substituting Li for K can lead to structural distortion, which improves the Curie temperature （To） greatly. By adding appropriate LiNbO3 content, piezoelectric constant d33 values reach 202-212 pC/N. Electromechanical coefficients of the planar mode reach 44.4%-46.8%. The dielectric loss is below 2.6%, which is much lower than reported （about 50%）. The To of （Na0.5K0.5-xLix）NbO3 （x=0.057-0.066） is in the range of 490-510℃, at least 70℃ higher than that of pure （Na0.5K0.5）NbO3 ceramics. The results show that （Na0.5K0.5-xLix）NbO3 ceramic is a kind of good lead-free high-temperature piezoelectric material.

关键词： Lead-free Piezoelectric Dielectric Morphotropic phase boundary

Enhanced ferro-/piezoelectric properties of tape-casting-derived Er^(3+)-doped Ba_(0.85)Ca_(0.15)Ti_(0.9)Zr_(0.1O3) optoelectronic thick films

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Journal of Advanced Ceramics 2020年第6期9卷 693-702页

作者： Jie XU Qiling LU Jinfeng LIN Cong LIN xinghua zheng Tengfei LIN Xiao WU Key Laboratory of Eco-materials Advanced Technology College of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

Er^(3+)-doped Ba_(0.85)Ca_(0.15)Ti_(0.9)Zr_(0.1O3)(xEr-BCTZ,x=0,0.005,0.01,0.015)multifunctional thick films were prepared by the tape-casting method,using sol-gel-derived nano-sized powders as the matrix *** surface morphologies,photoluminescence,and electrical properties were *** microstructures with pure perovskite structure were obtained in the thick *** doping an appropriate amount of Er^(3+),the samples exhibit superior up-conversion photoluminescence performance and simultaneously enhanced electrical *** addition,relatively higher texture fractions(with the largest value of 83.5%)were realized through introducing plate-like BaTiO_(3) templates to make the thick film grow by the[001]_(c) *** the ferro-/piezoelectric properties of the thick films were further improved,showing potential in the applications of micro-optoelectronic devices.

关键词： thick films texture ferroelectric piezoelectric photoluminescence

Review on Fiber-Based Thermoelectrics:Materials,Devices,and Textiles

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Advanced Fiber Materials 2023年第4期5卷 1105-1140页

作者： Yanan Shen Xue Han Pengyu Zhang Xinyi Chen Xiao Yang Ding Liu Xiaona Yang xinghua zheng Haisheng Chen Kun Zhang Ting Zhang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China Nanjing Institute of Future Energy System Nanjing 211135China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Textile Science&Technology(Ministry of Education) College of TextilesDonghua UniversityShanghai 201620China Innovation Academy for Light‑Duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Nanjing 211135China

With the development and prosperity of Internet of Things(IoT)technology,wearable electronics have brought fresh changes to our *** demands for low power consumption and mini-type wearable power systems for wearable electronics are more urgent than *** materials can efficiently convert the temperature difference between body and environment into electrical energy without the need for mechanical components,making them one of the ideal candidates for wearable power *** recent years,a variety of high-performance thermoelectric materials and processes for the preparation of large-scale single-fiber devices have emerged,driving the application of flexible fiber-based thermoelectric *** weaving thermoelectric fibers into a textile that conforms to human skin,it can achieve stable operation for long periods even when the human body is in *** this review,the complete process from thermoelectric materials to single-fiber/yarn devices to thermoelectric textiles is introduced *** for enhancing thermoelectric performance,processing techniques for fiber devices,and the wide applications of thermoelectric textiles are *** addition,the challenges of ductile thermoelectric materials,system integration,and specifications are discussed,and the relevant developments in this field are prospected.

关键词： Thermoelectric Fiber Material Device Textile

Thermally drawn multifunctional fibers: Toward the next generation of information technology

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InfoMat 2022年第7期4卷 98-119页

作者： Yanan Shen Zhe Wang hixun Wang Jiajia Wang Xiao Yang xinghua zheng Haisheng Chen Kaiwei Li Lei Wei Ting Zhang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijingChina Nanjing Institute of Future Energy System NanjingChina University of Chinese Academy of Sciences BeijingChina School of Electrical and Electronic Engineering Nanyang Technological UniversitySingaporeSingapore College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyangChina Key Laboratory of Bionic Engineering of Ministry of Education Jilin UniversityChangchunChina Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijingChina

As the fundamental building block of optical fiber communication technology,thermally drawn optical fibers have fueled the development and prosperity of modern information ***,the conventional step-index configured silica optical fibers have scarcely altered since their *** recent years,thermally drawn multifunctional fibers have emerged as a new yet promising route to enable unprecedented development in information *** adopting the well-developed preform-to-fiber manufacturing technique,a broad range of functional materials can be seamlessly integrated into a single fiber on a kilometer length scale to deliver sophisticated *** such as photodetection,imaging,acoustoelectric detection,chemical sensing,tactile sensing,biological probing,energy harvesting and storage,data storage,program operation,and information processing on fiber *** addition to the original light-guiding function,these flexible fibers can be woven into fab-rics to achieve large-scale personal health monitoring and interpersonal *** drawn multifunctional fibers have opened up a new stage for the next generation of information *** review article summarizes an overview of the basic concepts,fabrication processes,and developments of multifunctional *** also highlights the significant pro-gress and future development in information applications.

关键词： acoustoelectric fiber biological probe energy fiber integrated circuit fiber multifunctional fiber optoelectronic fiber

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三门峡黄河医院病房楼空调通风设计探讨

暖通空调 2011年第10期41卷 61-64页

作者：郑兴华中国水电十一局郑州科研设计有限公司

针对三门峡黄河医院新医院病房楼空调通风设计实例,详细介绍了医院诊疗部和住院部的通风空调设计,总结了一些特别的工程做法和设计方法,包括阻止放疗机房的射线通过管道传至室外的措施,住院部卫生间的排风处理等。

关键词：影像机房放疗机房舒适性空调

富钛BaO-TiO_2(Ti/Ba=4～4.5)系微波介质陶瓷

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稀有金属材料与工程 2007年第A1期36卷 484-486页

作者：林清平汤德平郑兴华福州大学材料科学与工程学院福建福州350002

采用固相反应法制备了富钛BaTi4+xO9+2x(x=0.0-0.50)微波介质陶瓷,探讨了TiO2含量以及烧结温度对物相组成和介电性能的影响。在1300～1350℃烧结BaTi4+xO9+h陶瓷即可达到约98%的相对密度。当x≤0.28时,BaTi4+xO9+2x陶瓷为BaTi4O9单相。... 详细信息

采用固相反应法制备了富钛BaTi4+xO9+2x(x=0.0-0.50)微波介质陶瓷,探讨了TiO2含量以及烧结温度对物相组成和介电性能的影响。在1300～1350℃烧结BaTi4+xO9+h陶瓷即可达到约98%的相对密度。当x≤0.28时,BaTi4+xO9+2x陶瓷为BaTi4O9单相。随TiO2含量的增加,BaTi4+xO9+2x陶瓷从BaTi4O9单相逐渐转变成以BaTi4O9为主相,同时出现TiO2和Ba2TigO20相,并且随烧结温度提高,TiO2含量较多的试样中出现更多的Ba2Ti9O20相。随TiO2含量的增加介电常数逐渐增大,而Qf值呈下降趋势。Qf值从x=0.0时的约40000GHz逐渐降低至x=0.50时的15000GHz。

关键词：微波介质陶瓷 BaTi4O9 介电性能物相分析

(1-x)Ba_4Sm_(9.33)Ti_(18)O_(54)-xCa_(0.61)Nd_(0.26)TiO_3系微波介质陶瓷

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硅酸盐学报 2006年第12期34卷 1437-1441页

作者：梁炳亮郑兴华倪维庆周小红福州大学材料学院福州350002 福州大学物理与信息工程学院福州350002

采用固相合成法制备了(1–x)Ba4Sm9.33Ti18O54–xCa0.61Nd0.26TiO3[(1–x)BST–xCNT]系微波介质陶瓷。探讨了组成、烧结温度对微波介质陶瓷结构、介电性能的影响。x<0.6时,(1–x)BST–xCNT陶瓷为正交结构的新型钨青铜单相。x≥0.6时,相... 详细信息

采用固相合成法制备了(1–x)Ba4Sm9.33Ti18O54–xCa0.61Nd0.26TiO3[(1–x)BST–xCNT]系微波介质陶瓷。探讨了组成、烧结温度对微波介质陶瓷结构、介电性能的影响。x<0.6时,(1–x)BST–xCNT陶瓷为正交结构的新型钨青铜单相。x≥0.6时,相继出现了第二相Sm2Ti2O7和钙钛矿相,最终形成钙钛矿单相。微波介质陶瓷的介电常数ε随x的增大持续升高,品质因子Qf值则先增大后迅速减小再急剧增大。1325～1350℃烧结样品的微波介电性能达到最佳:x=0时,ε=75,Qf=8985GHz,谐振频率温度系数τf=–8.2×10–6/℃;x=0.2时,ε=75,Qf=9552GHz,τf=–14.4×10–6/℃;x=1时,ε=108.9,Qf=14919GHz,τf=236.2×10–6/℃。

关键词：微波介质陶瓷新型钨青铜钙钛矿微波介电性能

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等离子熔射成形件的孔隙率测定

机械工艺师 2001年第2期 41-42页

作者：郑兴华高媛大连轻工业学校 116023 大连理工大学 116023

介绍一种等离子熔射法成形件的孔隙率测定方法、原理与步骤 ,并讨论与之相关的问题。

关键词：孔隙率测量等离子弧熔射成形孔隙率 PSFP