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Journal of Thermal Science 2020年第4期29卷 972-981页

作者： WANG Zhipeng cheng shuhao ZHUO Yuqun Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Beijing Engineering Research Center for Ecological Restoration and Carbon Fixation of Saline–alkaline and Desert Land Tsinghua UniversityBeijing 100084China China Institute of Atomic Energy Beijing 102413China

The flow and heat transfer characteristics of Maxwell fluid in a pipe under pulsating pressure gradient were studied. The governing equations were made dimensionless. The Rubin boundary condition was adopted. The flow field was solved theoretically and the temperature field was obtained using finite volume method. A general model suitable for various fluctuating characteristics and physical parameters was established. The Deborah number(De) was used to characterize the fluidity of the fluid. The influence of De on flow and temperature fields was evaluated. The Nusselt number and start-up process of Maxwell fluid were studied. Results showed that the influence of De on flow field was greater than that on temperature field. The effect of De on Nusselt number was irregular and related to the oscillation parameters. The over-shooting amplitude and oscillation time of axis center velocity in start-up flow grow larger with De.

关键词： Maxwell fluid pulsating flow Hagen-Poiseuille law Deborah number start-up flow

Experimental Study on the Characteristics of Water Vapor Generation from Gas-washing Bottle and Injector

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Journal of Thermal Science 2019年第1期28卷 82-87页

作者： WANG Zhipeng WANG Lang ZHAO Angran cheng shuhao YANG Ruiming ZHUOYuqun TONG Huiling Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power Engineering Tsinghua University

Gas-washing and water injection are two commonly used methods in generating certain moisture content in gas flow stream, but the control accuracy of these methods remains uncertain. The purpose of the study is to investigate the characteristic of water vapor generation of the two methods. The temperature and humidity recorder and FTIR gas analyzer have been adopted to monitor the moisture content in tests. It has been revealed that, in gas-washing process, the moisture content in gas stream is well below saturation, and long time is required before moisture content stabilized after water bath temperature or carrier gas flow rate changed. Water injection pump could directly control the amount of water injected into gas stream. However, the moisture content generated in this way is not stable but oscillates in cycles, whose frequency and magnitude are closely related to water injection amount.

关键词： water vapor FTIR gas-washing bottle injector temperature and humidity recorder

Impacts of different designed microstructures on creep performance of a Ni-based wrought superalloy

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Progress in Natural Science:Materials International 2023年第5期33卷 625-633页

作者： Hao Liu Xinbao Zhao Yuan cheng Jiachen Xu shuhao cheng Quanzhao Yue Yong Yuan Yuefeng Gu Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and Engineering Zhejiang University Polytechnic Institute Zhejiang University State Key Laboratory of Silicon and Advanced Semiconductor Materials Zhejiang University Xi'an Thermal Power Research Institute Co.Ltd.

The creep behavior of a novel Ni-based wrought superalloy with varying aging states, classified as large underaged(UA), little UA, and little over-aged(OA) states, was investigated at a temperature higher than the intragrain/grain-boundary iso-strength temperature(750°C/250 MPa). In the samples before creep test, there are spherical γ’precipitates homogeneously dispersed within the γ matrix and carbides precipitated at grain boundaries(GBs). After creep tests, precipitate-free zones(PFZs) appear on grain boundaries, with a large blocklike γ’phase present between carbides and PFZs, potentially serving as initiation sites for cracks. Little UA state samples exhibit the strongest creep resistance and intergranular fracture. The dominant creep deformation mechanism in the intra-grain is a combination of Orowan process involving slip and climb of matrix dislocations and shearing of γ’precipitates. The results indicate that the optimizing the grain boundary microstructure may be more important than the change of intragranular microstructure when the creep temperature exceeds the isostrength temperature.

关键词： Ni-based wrought superalloy Intragranular microstructure Creep performance

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地铁隧道横断面连续提取

测绘通报 2020年第S1期 45-50页

作者：程书豪邹进贵武汉大学测绘学院湖北武汉430079

地铁隧道变形监测对地铁施工及安全运营有很重要的意义,现阶段广泛利用三维激光扫描技术对地铁隧道进行变形监测。变形分析时需要提取地铁隧道的断面,但目前没有专门的软件实现对地铁隧道断面的连续提取,因此本文对地铁隧道断面连续提... 详细信息

地铁隧道变形监测对地铁施工及安全运营有很重要的意义,现阶段广泛利用三维激光扫描技术对地铁隧道进行变形监测。变形分析时需要提取地铁隧道的断面,但目前没有专门的软件实现对地铁隧道断面的连续提取,因此本文对地铁隧道断面连续提取进行了研究,总结了现有隧道断面提取的方法,针对投影法提取隧道断面时受隧道边界噪点影响的问题,提出了利用统计滤波结合迭代去噪的方法,并开发了断面连续提取的软件,并结合武汉地铁隧道三维激光扫描数据进行试验。结果表明,该方法能够精确地提取隧道边界,降低了边界噪点对隧道断面提取结果的影响。

关键词：三维激光扫描地铁隧道变形监测横断面提取统计滤波

High resolution and high signal-to-noise ratio imaging with nearfield high-order optical signals

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Nano Research 2022年第9期15卷 8345-8350页

作者： Fei Wang Shuming Yang Shaobo Li shuhao Zhao Biyao cheng chengsheng Xia State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

The properties of near-field optics have always been the focus of nano-measurement *** 11th order effective nearfield optical signal with an incident laser wavelength of 1,550 nm is obtained using a platinum-coated optical probe(Pt–Si probe).The experimental results show that the local electric field intensity of the Pt–Si probe is nearly 30 times higher than that of silicon probe(Si probe).Therefore,the highest 7th order near-field optical imaging results are obtained with the Pt–Si ***,near-field optical imaging is performed on samples such as gold grids and carbon nanotubes using the Pt–Si *** measurement results show that the high-order signal has the characteristics of less background,higher signal-to-noise ratio,and resolution up to 5.7 nm.

关键词： high-order optical signal local electric field enhancement high resolution optical probe

Fabricating a PVDF skin for PEO-based SPE to stabilize the interface both at cathode and anode for Li-ion batteries

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Journal of Energy Chemistry 2022年第7期31卷 356-362,I0010页

作者： Qi Ye Haoyue Liang shuhao Wang Can Cui cheng Zeng Tianyou Zhai Huiqiao Li State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Poly(ethylene oxide)(PEO)-based solid polymer electrolyte is always the most promising candidate for preparing thinner, lighter and safer lithium-ion batteries. However, the lithium dendrites growth of lithium anode and the high-voltage oxidation of cathode are easy to cause the PEO-based battery *** way to deal with the different challenges on both sides of the anode and cathode is pursued all the time. In this study, we reported a new strategy to construct the PVDF/PEO/PVDF three-layer structure for solid polymer electrolyte(marked as PVDF@PEO) using PVDF as the functional “skin”. The PVDF@PEO electrolyte can effectively prevent from the lithium dendrites, and shows a stable cycling life over1000 h in the Li/PVDF@PEO/Li cell. In addition, the PVDF@PEO electrolyte exhibits higher oxidation resistance and can be matched with high-voltage LiCoO_(2) cathode. The Li/PVDF@PEO/LiCoO_(2) cell delivered a specific capacity of about 150 m Ah g^(-1) over 150 cycles and maintained good cycling stability. Our research provides insights that the polymer electrolytes constructed with PVDF functional “skin” can simultaneously meet the challenges of both anode and cathode in solid-state lithium-ion batteries(SSLIBs).

关键词： PVDF PEO Solid-state lithium-ion batteries Cathode Anode

Directional Electromagnetic Interference Shielding Based on Step-Wise Asymmetric Conductive Networks

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Nano-Micro Letters 2022年第1期14卷 262-277页

作者： Bai Xue Yi Li Ziling cheng Shengdu Yang Lan Xie shuhao Qin Qiang Zheng Department of Polymer Materials and Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang 550025People’s Republic of China National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane ProcessesGuiyang 550014People’s Republic of China College of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024People’s Republic of China

Some precision electronics such as signal transmitters need to not only emit effective signal but also be protected from the external electromagnetic(EM)***,directional electromagnetic interference(EMI)shielding materials(i.e.,when the EM wave is incident from different sides of the sample,the EMI shielding effectiveness(SE)is rather different)are strongly required;unfortunately,no comprehensive literature report is available on this research ***,Nicoated melamine foams(Ni@MF)were obtained by a facile electroless plating process,and multiwalled carbon nanotube(CNT)papers were prepared via a simple vacuum-assisted self-assembly ***,step-wise asymmetric poly(butylene adipate-co-terephthalate)(PBAT)composites consisting of loose Ni@MF layer and compact CNT layer were successfully fabricated via a facile solution encapsulation *** step-wise asymmetric structures and electrical conductivity endow the Ni@MF/CNT/PBAT composites with unprecedented directional EMI shielding *** the EM wave is incident from Ni@MF layer or CNT layer,Ni@MF-5/CNT-75/PBAT exhibits the total EMI SE(SET)of 38.3 and 29.5 dB,respectively,which illustrates theΔSET of 8.8 *** work opens a new research window for directional EMI shielding composites with step-wise asymmetric structures,which has promising applications in portable electronics and next-generation communication technologies.

关键词： Solution encapsulation Step-wise asymmetry Directional electromagnetic interference shielding Electrical conductivity Vacuum-assisted self-assembly

Thermoelectric characteristics of semiconductor minerals in earth's deep crust and their seismogenic significance

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Geoscience Frontiers 2022年第2期13卷 159-164页

作者： shuhao Wang Junfeng Shen M.Santosh Yuanyuan Li cheng-Xue Yang Liangkun Ma School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia

Geo-electric anomalies are generated during the process of stress accumulation and release associated with ***,the mechanism of these anomalies remains *** on the analysis of thermoelectric characteristics of semiconductor minerals of the earth’s deep crust such as graphite,ferrosilicon alloy,magnetite etc.,we perform finite element analysis to evaluate the principles governing the thermoelectric power generated by minerals and *** results show that graphite,ferrosilicon alloy and magnetite all exhibit Seebeck effect and can be *** the thermo-electric field can be enhanced with the activation temperature increases,the content of thermoelectric minerals increases,the size of aggregates increases,and the spacing of thermoelectric minerals grains *** processes would generate a similar thermal *** natural semiconductor minerals in this thermal field show a thermoelectric effect,forming a thermoelectric field that interferes with the background electric *** study indicates that thermoelectric effect may have an important influence on the formation of geoelectric field.

关键词： Natural semiconductor minerals Seebeck effects Geoelectric anomalies Earthquakes Deep crust

A flat-based plasmonic fiber probe for nanoimaging

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Nano Research 2023年第5期16卷 7545-7549页

作者： Fei Wang Shaobo Li shuhao Zhao Ze Zhang Peirui Ji chengsheng Xia Biyao cheng Guofeng Zhang Shuming Yang State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong UniversityXi’an 710049China

The difficulty of obtaining high-intensity localized light spots for optical probes leads to their lack of good applications in *** we demonstrate a Fabry–Pérot resonance flat-based plasmonic fiber probe(FPFP).The simulation results show that the probe can obtain a nanofocusing spot at the tip with the radially polarized *** Fabry–Pérot interference structure is used to control the plasmon propagation on the surface of the probe,it effectively improves the local spot intensity at the ***,the experimental results verify that the FPFP(tip curvature radius is 20 nm)prepared by chemical etching method can obtain a nanofocusing spot at the *** nanoimaging of the gold slit structure demonstrates the nanoimaging capability of the FPFP,the 36.9 nm slit width is clearly identified by the FPFP.

关键词： optical probe nanoimaging controlling plasmon propagation nanofocusing local electric field enhancement

High-performance broadband flexible photodetector based on Gd_(3)Fe_(5)O_(12)-assisted double van der Waals heterojunctions

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Microsystems & Nanoengineering 2023年第4期9卷 157-165页

作者： Ze Zhang Peirui Ji Shaobo Li Fei Wang Shengmei He Yiwei cheng shuhao Zhao Kaili Li Xiaomin Wang Yu Wang Shuming Yang State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’anShaanxiChina MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi’an Jiaotong UniversityXi’anShaanxiChina

Flexible photodetectors are fundamental components for developing wearable systems,which can be widely used for medical detection,environmental monitoring and flexible ***,compared with 3D materials,lowdimensional materials have degraded performance,a key challenge for current flexible ***,a highperformance broadband photodetector has been proposed and *** combining the high mobility of graphene(Gr)with the strong light–matter interactions of single-walled carbon nanotubes(SWCNTs)and molybdenum disulfide(MoS2),the flexible photodetector exhibits a greatly improved photoresponse covering the visible to near-infrared ***,a thin layer of gadolinium iron garnet(Gd_(3)Fe_(5)O_(12),GdlG)film is introduced to improve the interface of the double van der Waals heterojunctions to reduce the dark *** SWCNT/GdIG/Gr/GdIG/MoS2 flexible photodetector exhibits a high photoresponsivity of 47.375 A/W and a high detectivity of 1.952×1012 Jones at 450 nm,a high photoresponsivity of 109.311 A/W and a high detectivity of 4.504×10^(12) Jones at 1080 nm,and good mechanical stability at room *** work demonstrates the good capacity of GdIGassisted double van der Waals heterojunctions on flexible substrates and provides a new solution for constructing high-performance flexible photodetectors.

关键词： performance double constructing