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Stress analysis of full-length grouted bolt under shear deformation of anchor interface

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Journal of Mountain Science 2022年第11期19卷 3286-3301页

作者： ZHU zheng-de SHU Xiao-yun li zhe TIAN Hong-ming TIAN Yun College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Civil Engineering Shaoxing UniversityShaoxing 312000China China Railway Design Corporation Tianjin 300251China

The bolt anchoring force is closely related to the shear properties of the anchor interface. The shear stress distribution of full-length grouted bolts is analyzed based on the stress-strain relationship among the bolt, grout, rock mass and bond interface,considering the shear properties of the grout and contact interface bonding behavior. In this case, the interfacial shear stress of the grout and rock mass and the bolt axial force are obtained under pull-out and normal working conditions. The results show that the peak shear stress of the interface with the shear deformation of the bond interface is significantly lower than that without it when the pull-out force is applied. When designing bolt parameters of grade IV and V rock mass, the relative deformation between the rock mass and anchor should be considered, with a “unimodal” to “bimodal” shear stress *** the case of a low elastic modulus of rock masses,both the shear stress concentration and distribution range are obvious, and the neutral point is near the bolt head. As the elastic modulus increases, the shear stress concentration and distribution range are reduced, and the neutral point moves towards the distal end. As a result, the optimum length of fulllength grouted bolts can be determined by in-situ pull-out tests and decreases with the increased elastic modulus of the rock mass.

关键词： Full length grouted bolt Neutral point Interfacial shear stress Bolt pull out condition Normal working condition

Effect of Tai Chi on Cardiac and Static Pulmonary Function in Older Community-Dwelling Adults at Risk of Ischemic Stroke: A Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2019年第8期25卷 582-589页

作者： zheNG Guo-hua zheNG Xin li Jun-zhe DUAN Ting-jin TAO Jing CHEN li-dian College of Nursing and Health Management Shanghai University of Medicine and Health Sciences Shanghai (201318) China College of Rehabilitation Medicine Fujian University of Traditional Chinese Medicine Fuzhou (350122)China Department of Physical Education Fujian University of Traditional Chinese Medicine Fuzhou (350122)China Fujian Key Laboratory of Rehabilitati on Tech no logy Fujia n Un iversity of Traditional Chinese Medicine Fuzhou (350122)China Collaborative Inno vation Cen ter for Rehabilitati on Tech no logy Fujian University of Traditional Chinese Medicine Fuzhou (350122)China

Objective: To evaluate the effect of tai chi exercise on cardiac and static lung function for older community-dwelling adults at risk of ischemic stroke. Methods: A total of 170 older community-dwelling adults (aged 55–75 years old) at risk of ischemic stroke were allocated to either tai chi training group (85 cases, five 60-min sessions of tai chi training per week for 12 weeks) or control group (85 cases, usual pbysical activity for 12 weeks) using a computer-generated randomization. The echocardiographic parameters of cardiac structure, cardiac function and static lung function were measured at baseline, after 12 weeks of intervention and additional 12-week follow-up period by a blinded professional staff member using a color Doppler ultrasound imaging device or a cardiopulmonary function instrument. The t test and linear mixed model based on the intention-to-treat analysis principle was used to calculate the effect. The adverse effect was observed. Results: Most of echocardiographic parameters on the cardiac structure, cardiac function and static lung function between the tai chi group and control group did not have a significant difference either post 12-week intervention or additional 12-week follow-up period. Only three parameters involving in right ventricular diameter (P=0.024), main pulmonary artery diameter (P=0.002) and vital capacity maximum (P=0.036) were beneficial to be improved in the tai chi group compared to the control group by the analysis of mixed linear model. No adverse effects were found during the intervention period. Conclusions: The 12-week tai chi exercise did not have an obvious beneficial effect on cardiac structure, cardiac function and static lung function in older community-dwelling adults at risk of ischemic stroke.(Trial registration No. ChiCTR-TRC-13003601)

关键词： tai chi cardiac structure and function static lung function ischemic stroke randomized controlled trial

Ultrasensitive Indium Phosphide Nanomembrane Wearable Gas Sensors

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Energy & Environmental Materials 2024年第6期7卷 209-217页

作者： Shiyu Wei Tuomas Haggren zhe li Hark Hoe Tan Chennupati Jagadish Antonio Tricoli Lan Fu Department of Electronic Materials Engineering Australian Research Council Centre of Excellence for Transformative Meta-Optical SystemsResearch School of PhysicsThe Australian National UniversityCanberraACT 2600Australia Nanotechnology Research Laboratory Research School of ChemistryCollege of ScienceThe Australian National UniversityCanberraACT 2600Australia Nanotechnology Research Laboratory Faculty of EngineeringThe University of SydneyCamperdownNSW 2006Australia

Air quality is deteriorating due to continuing urbanization and *** particular,nitrogen dioxide(NO_(2))is a biologically and environmentally hazardous byproduct from fuel combustion that is ubiquitous in urban *** address this issue,we report a high-performance flexible indium phosphide nanomembrane NO_(2)sensor for real-time air quality *** ultralow limit of detection of~200 ppt and a fast response have been achieved with this device by optimizing the film thickness and doping concentration during indium phosphide *** varying the film thickness,a dynamic range of values for NO_(2)detection from parts per trillion(ppt)to parts per million(ppm)level have also been demonstrated under low bias voltage and at room temperature without additional light *** measurements show an adequately stable response after repeated ***-site testing of the sensor in a residential kitchen shows that NO_(2)concentration from the gas stove emission could exceed the NO_(2)Time Weighted Average limit,i.e.,200 ppb,highlighting the significance of real-time ***,the indium phosphide nanomembrane sensor element cost is estimated atlicability,our indium phosphide nanomembrane sensors offer a promising solution for a variety of air quality monitoring applications.

关键词： air quality monitoring flexible III-V semiconductors nanofilm ultrathin

A Comparative Study of Charging Voltage Curve Analysis and State of Health Estimation of lithium-ion Batteries in Electric Vehicle

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Automotive Innovation 2019年第4期2卷 263-275页

作者： Xuebing Han Xuning Feng Minggao Ouyang Languang Lu Jianqiu li Yuejiu zheng zhe li School of Vehicle and Mobility State Key Laboratory of Automotive Safety and EnergyTsinghua UniversityBeijing 100084China College of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China

lithium-ion(li-ion)cells degrade after repeated cycling and the cell capacity fades while its resistance ***-dation of li-ion cells is caused by a variety of physical and chemical mechanisms and it is strongly influenced by factors including the electrode materials used,the working conditions and the battery *** present,charging voltage curve analysis methods are widely used in studies of battery characteristics and the constant current charging voltage curves can be used to analyze battery aging mechanisms and estimate a battery’s state of health(SOH)via methods such as incremental capacity(IC)*** this paper,a method to fit and analyze the charging voltage curve based on a neural network is proposed and is compared to the existing point counting method and the polynomial curve fitting *** neuron parameters of the trained neural network model are used to analyze the battery capacity relative to the phase change reactions that occur inside the *** method is suitable for different types of batteries and could be used in battery management systems for online battery modeling,analysis and diagnosis.

关键词： lithium-ion battery Capacity fade Charging voltage curve Neural networks Electric vehicle

Defect Passivation on Lead-Free CsSnI_(3) Perovskite Nanowires Enables High-Performance Photodetectors with Ultra-High Stability

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Nano-Micro Letters 2022年第12期14卷 481-490页

作者： zheng Gao Hai Zhou Kailian Dong Chen Wang Jiayun Wei zhe li Jiashuai li Yongjie liu Jiang Zhao Guojia Fang International School of Microelectronics Dongguan University of TechnologyDongguan 523808GuangdongPeople’s Republic of China Key Lab of Artificial Micro-and Nano-Structures of Ministry of Education of China School of Physics and TechnologyWuhan UniversityWuhan 430072People’s Republic of China Faculty of Physics and Electronic Science Hubei UniversityWuhan 430062People’s Republic of China

In recent years,Pb-free CsSnI_(3) perovskite materials with excellent photoelectric properties as well as low toxicity are attracting much atten-tion in photoelectric ***,deep level defects in CsSnI_(3),such as high density of tin vacancies,structural deformation of SnI_(6)−octahedra and oxidation of Sn^(2+)states,are the major challenge to achieve high-performance CsSnI_(3)-based photoelectric devices with good *** this work,defect passivation method is adopted to solve the above issues,and the ultra-stable and high-performance CsSnI_(3) nanowires(NWs)photodetectors(PDs)are fabricated via incorporating 1-butyl-2,3-dimethylimidazolium chloride salt(BMIMCl)into *** materials analysis and theoretical calculations,BMIM+ions can effectively passivate the Sn-related defects and reduce the dark current of CsSnI_(3) NW *** further reduce the dark current of the devices,the polymethyl methacrylate is introduced,and finally,the dual passivated CsSnI_(3) NWPDs show ultra-high performance with an ultra-low dark current of 2×10^(-11) A,a responsivity of up to 0.237 A W^(−1),a high detectivity of 1.18×10^(12) Jones and a linear dynamic range of 180 ***,the unpackaged devices exhibit ultra-high stability in device performance after 60 days of storage in air(25℃,50% humidity),with the device performance remaining above 90%.

关键词： Pb-free Perovskite CsSnI_(3) Photodetector Nanowire

Epitaxial Growth of 4H-SiC on 4° Off-Axis Substrate for Power Devices

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Chinese Physics Letters 2011年第9期28卷 257-259页

作者： li zhe-Yang HAN Ping li Yun NI Wei-Jiang BAO Hui-Qiang li Yu-Zhu Jiangsu Provincial Key Lab of Advance Photonic and Electronic Materials Department of PhysicsNanjing UniversityNanjing 210093 National Key Laboratory of Monolithic Integrated Circuits and Modules Nanjing Electronic Devices InstituteNanjing 210016 TanKeBlue Semiconductor CO. Ltd.Beijing 100190

Homo-epitaxial layers are successfully grown on Si-face 4°off−axis 4H-SiC substrates using the horizontal hot-wall chemical vapor deposition *** smooth surface without morphological defects is obtained by the optimized in situ etching process and growth *** diodes fabricated on the epilayer present a typical I–V *** is the first report of Schottky diodes fabricated on 4°off-axis 4H-SiC substrates made in China.

关键词： temperature Schottky diodes

Ternary solvent-processed efficient organic solar cells based on a new A-DA'D-A acceptor derivative employing the 3^(rd)-position branching side chains on pyrroles

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Chinese Chemical Letters 2021年第1期32卷 229-233页

作者： Yu Chen Honggang Chen Huilan Guan Wei liu zhe li Hui liu Yongfang li Yingping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

Recent advances in non-fullerene acceptors(NFAs),typically Y6,have driven power conversion efficiency(PCE) of single-junction orga nic solar cells(OSCs) over 16%.Mea nwhile,it becomes essential to know how to adopt simple strategies to further improve device *** this work,a new A-DA'D-A acceptor derivative,Y19-N3 employing 3-ethylheptyl branched at the 3^(rd)-position instead of 2-ethylhexyl on the pyrroles of Y19 is *** selection of an appropriate solvent in casting device is implemented to maximize the photovoltaic ***-T:Y19-N3-based OSCs treated with a ternary solvent of CF/CB(1:3,v/v) and 0.8% DIO exhibit the optimal PCE of 13.77% here,with the significantly improved V_(oc)(0.78 V) and FF(0.72) as well as the high J_(sc)(24.46 mA/cm^(2)).Further characterizations indicate that this ternary solvent-treated PBDB-T/Y19-N3 film exhibits the more appropriate morphological features with the highly efficient charge generation and collection as well as the more balanced electron and hole *** work combines molecular design and device engineering to improve the photovoltaic properties,which is important to the development of OSCs.

关键词： Organic solar cells Side chain engineering Ternary solvent Increased efficiency Balanced mobilities

Improved electrochemical hydrogen storage capacity of Ti45Zr38Ni17 quasicrystal by addition of ZrH2

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Journal of Materials Science & Technology 2018年第6期34卷 995-998页

作者： Jianxun Zhao Xiaojie Zhai Xing Tao zhe li Qingshuang Wang Wanqiang liu limin Wang School of Materials Science and Engineering Changchun University of Science and Technology Changchun 130022 China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry CAS Changchun 130022 China

Ti45Zr38Ni37 ＋ xZrH2 （x = 5,10, 15 and 20 wt%） composite materials are produced by ball milling for 20 rain. The results of XRD measurement show that the composite materials contain icosahedral quasicrystal phase （I-phase）, FCC phase with a Ti2Ni type crystal and C14 Laves phase. After adding ZrH2, the composite materials include not only the individual phases mentioned above, but also the ZrH phase. These composite materials are used as the negative electrode material of the nickel-metal hydride batteries. The electrochemical hydrogen storage characteristics of the material after adding ZrH is investigated. The TiasZr38Ni17 ＋xZrH2 （x=5, 10, 15 and 20wt%） composite material has reached the maximum discharge capacity （83.2 mA h/g） when x equals 10. This maximum discharge capacity is much higher than that of Ti45Zr38Ni17 alloy without ZrH. After adding ZrH2. the high-rate discharge ability and the cycling stability are enhanced simultaneously. The improvement of the electrochemical properties can be attributed to the synergistic effects of ZrH2, and the synergistic effects in the composite electrodes are probably attributed to the entry of most of hydrogen atoms from weakly bond strength of the Zr-H to the l-phase structure in electrochemical reaction.

关键词： Quasicrystals Electrochemical measurements Electrochemical properties Energy storage

Primary biliary cirrhosis:What do autoantibodies tell us?

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World Journal of Gastroenterology 2010年第29期16卷 3616-3629页

作者： Chao-Jun Hu Feng-Chun Zhang Yong-zhe li Xuan Zhang Department of Rheumatology and Clinical Immunology Peking Union Medical College Hospital Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100032China

Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown *** predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruction of small-and medium-size intrahepatic bile ducts,portal inflammation and progressive scarring,which without proper treatment can ultimately lead to fibrosis and hepatic *** autoantibodies are crucial tools for differential diagnosis of *** it is currently accepted that antimitochondrial antibodies are the most important serological markers of PBC,during the last five decades more than sixty autoantibodies have been explored in these patients,some of which had previously been thought to be specific for other autoimmune diseases.

关键词： Primary biliary cirrhosis Autoimmune disease Autoantibody Anti-mitochondrial antibody Antigp210 antibody Anti-sp100 antibody Anti-centromere antibodies