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Description on the female spider of Sinanapis wuyi Jin &Zhang(Araneae:Anapidae)

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动物分类学报 2014年第2期39卷 236-247页

作者： zhe Yuan xian-Jin Peng College of life Sciences Hunan Normal University

The present paper deals with the female supplement of Sinanapis wuyi Jin ＆ Zhang, 2013 from Dawei Mountains, Hunan Province, China. Descriptions and diagnosis of Sinanapis wuyi Jin ＆ Zhang, 2013 are given. Detailed ... 详细信息

关键词： Anapidae taxonomy morphology female supplement China

Application of BP Neural Network in Prediction of Cu-Pb Composite Plates Properties

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Journal of Harbin Institute of Technology(New Series) 2013年第5期20卷 36-40页

作者： Sheng-Gang Zhou li-Da Sun Pei-xian Zhu Jin Zhang zhe Zhang Faculty of Material Science and Engineering Kunming University of Science and Technology College of Science Honghe University

： The artificial neural networks（ANN） , which have broad application, are proposed to develop Cu-Pb composite plates materials. Based on the back propagation（BP） algorithm of the forward muhilayer perceptron, the model to predict the shear stress under different ingredient of the third element and the hot dipping temperature for Cu-Pb composite plates are established. Then the relational model among the third element, hot dipping temperature and shear stress by using the limited data are studied, and the forecast average error is 4%. This model can satisfy the requirements of the precision of forecast in the project experiment process. The results show that the corresponding shear stress is greater when the third element in the element contains more Sn; the most appropriate temperature of hot-dip plating about is 340℃, ＇after predicted with lead/the third element/the best performance of copper composite material element of the third group is the one-element Sn, hot dip plating temperature is 335 ℃ ; two-element is 90% Sn 10% Bi, and hot dip plating temperature is 345 ℃. The prediction results can be used for a reference in instructing the further experimental design.

关键词： BP neural network composite interface the third element shear stress

Influence of a multi-step process on the thickness reduction error of sheet metal in a flexible rolling process

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 76-85页

作者： Yi li Ming-zhe li Kai liu Dieless Forming Technology Center Roll Forging Institute Jilin University College of Materials Science and Engineering Jilin University

Flexible rolling is a forming process based on thickness reduction, and the precision of thickness reduction is the key factor affecting bending deformation. The major purpose of the present work is to solve the problem of bending deformation error caused by insufficient thickness reduction. Under the condition of different rolling reductions with the same sheet thickness and the same thickness reduction with different sheet thicknesses, the thickness reduction error of sheet metal is analyzed. In addition, the bending deformation of sheet metal under the same conditions is discussed and the influence of the multi-step forming process on the thickness reduction error is studied. The results show that, under the condition of the same sheet thickness, the thickness reduction error increases with increasing rolling reduction because of an increase in work hardening. As rolling reduction increases, the longitudinal bending deformation decreases because of the decrease of the maximum thickness difference. Under the condition with the same thickness reduction, the thickness reduction error increases because of the decrease of the rolling force with increasing sheet thickness. As the sheet thickness increases, the longitudinal bending deformation increases because of the increase in the maximum thickness difference. A larger bending deformation is divided into a number of small bending deformations in a multi-step forming process, avoiding a sharp increase in the degree of work hardening; the thickness reduction error is effectively reduced in the multi-step forming process. Numerical simulation results agree with the results of the forming experiments.

关键词： flexible rolling convex surface numerical simulation thickness reduction error multi-step forming process

Ballistic deficit compensation method for a large-volume HPGe detector at high count rates

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Nuclear Science and Techniques 2016年第3期27卷 123-131页

作者： Chuan-Yun Xiong Ming-zhe liu Zhuo Zuo xian-Guo Tuo State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

A large-volume HPGe detector normally has a severe ballistic deficit due to its long rise time of the output *** the trapezoidal shaping algorithm adopted as a remedy to deal with the signals,the algorithm cannot fully eliminate the ballistic deficit in the case of a high counting *** resolve the problem,we propose a ballistic deficit compensation method that is based on the measurement of rise time of the signals before *** find that the ballistic deficit after trapezoidal shaping has little relation to the time constant,but shows a quadratic relationship with the rise time and has a negative correlation with the shaping *** the case of high count rates,the high resolution is handled by fitting the curve to the rise time and the amplitude deficit of the signal after shaping and by compensating for the signal amplitude after trapezoidal *** indicate that when the count rate is about 100 kcps,the resolution of Co-60 improves from traditional 2.32 up to 1.91 keV,thus reaching a higher level.

关键词：高计数率补偿方法 HPGe探测器亏损弹道大体积输出信号上升时间

Fast nuclide identification based on a sequential Bayesian method

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Nuclear Science and Techniques 2021年第12期32卷 116-127页

作者： Xiao-zhe li Qing-xian Zhang He-Yi Tan Zhi-Qiang Cheng liang-Quan Ge Guo-Qiang Zeng Wan-Chang Lai Chengdu University of Technology The College of Nuclear Technology and Automation EngineeringChengdu 610059China

The rapid identification of radioactive substances in public areas is ***,traditional nuclide identification methods only consider information regarding the full energy peaks of the gamma-ray spectrum and require long recording times,which lead to long response *** this paper,a novel identification method using the event mode sequence(EMS)information of target radionuclides is *** EMS of a target radionuclide and natural background radiation were established as two different probabilistic models and a decision function based on Bayesian inference and sequential testing was *** proposed detection scheme individually processes each *** a photon is detected and accepted,the corresponding posterior probability distribution parameters are estimated using Bayesian inference and the decision function is ***,value of the decision function is compared to preset detection thresholds to obtain a detection ***ments on different target radionuclides(137Cs and 60Co)were *** count rates of the regions of interest(ROI)in the backgrounds between[651,671],[1154,1186],and[1310,1350]keV were 2.35,5.14,and 0.57 CPS,*** experimental results demonstrate that the average detection time was 6.0 s for 60Co(with an activity of 80400 Bq)at a distance of 60 cm from the *** average detection time was 7 s for 137Cs(with an activity of 131000 Bq)at a distance of 90 cm from the *** results demonstrate that the proposed method can detect radioactive substances with low activity.

关键词： Natural radiation Nuclide identification Sequential testing Nuclear safety

Particles attrition of binary mixtures in the coal-fueled chemical looping system based on fluidized bed

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Particuology 2024年第3期86卷 281-290页

作者： Heyu li zhe Sun Yan Cao Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Bejing 100049China CAS Key Laboratory of Renewable Energy Guangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China College of Chemistry and Chemical Engineering Anhui UniversityHefei230601China

In this work,a reactive air jet attrition device with auto-recording and collection of elutriated fines was *** established insights into the physiochemical interaction and further correlated attrition behaviors between char and oxygen carriers under various operation *** attrition rate increased by over 110% upon the introduced CO_(2),which brought in the significant effect of thermo-chemical stress,similarly in effects of the increased char addition ratio and the decreased sizes of char or hematite in different *** the char-hematite co-attrition process,the elutriated carbon loss of char with poor mechanical strength was found to be over 10%,while the reactive iron loss of hematite was found to be 6.3%,and was enriched in elutriated *** reaction-derived thermochemical stress and the collision-derived mechanical stress jointly controls the particle attrition during the cyclic transformation of oxygen carrier particles in coal-fueled chemical looping fluidization,especially sig-nificant in its reduction stage.

关键词： Attrition Binary species Chemical looping Oxygen carrier CO_(2)capture

Coulomb Screening and Plasmon Excitation in Graphene at Finite Temperature

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Communications in Theoretical Physics 2009年第8期52卷 361-364页

作者： li Zhao-zhe School of Physics Peking University Beijing 100871 China

By using the random phase approximation (RPA) in many-body perturbation theory,we calculate thepolarization function of the electron gas in graphene at finite *** on this,we calculate the temperaturedependent dielectric function ∈(q).The thermal effect on ∈(q) in various q regions is *** temperaturedependence is found to be *** also investigate the plasmon dispersion relation at finite temperature,with thezero-temperature relation as a special *** result is in good agreement with recent experimental data.

关键词： graphene polarization function dielectric function plasmon

Nanodiamond/Ti_(3)C_(2) MXene-coated quartz crystal microbalance humidity sensor with high sensitivity and high quality factor

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Rare Metals 2024年第6期43卷 2719-2729页

作者： Yao Yao Qiao Chen Yan-Qi li xian-He Huang Wei-Wei ling zhe-MiaoXie Jia-QiWang Chang-Ming Chen College of Communication Engineering Chengdu University of Information TechnologyChengdu 610225China School of Automation Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Advanced Micro-/Nano-Devices Lab Department of Systems Design EngineeringUniversity of WaterlooWaterlooON N2L 3GlCanada

To address the challenge of achieving both high sensitivity and a high quality factor in quartz crystal microbalance(QCM)humidity sensors,a nanodiamond(ND)/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor was *** material characteristics of ND,Ti_(3)C_(2)MXene,and ND/Ti_(3)C_(2)MXene composite were analyzed by transmission electron microscopy(TEM)and Fourier transform infrared(FTIR)*** experimental results demonstrated that the hydrophilic ND nanoparticles coated on Ti_(3)C_(2) MXene nanosheet prevented the self-stacking of Ti_(3)C_(2)MXene and enhanced the sensitivity of Ti_(3)C_(2) MXene-based QCM humidity ***,the high mechanical modulus of Ti_(3)C_(2) MXene material helped ND/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor to achieve a high quality factor(>20,000).ND/Ti_(3)C_(2)MXene compositecoated QCM humidity sensor exhibited a sensitivity of 82.45 Hz/%RH,a humidity hysteresis of 1.1%RH,fast response/recovery times,acceptable repeatability,and good stability from 11.3%RH to 97.3%*** response mechanism of ND/Ti_(3)C_(2) MXene composite-coated QCM humidity sensor was analyzed in combination with a bi-exponential kinetic adsorption ***,the potential application of ND/Ti_(3)C_(2)MXene composite-coated QCM humidity sensor was demonstrated through its frequency response to wooden blocks with different moisture contents.

关键词： Humidity sensor Quartz crystal microbalance Nanodiamond Ti_(3)C_(2)MXene High quality factor

Enhanced thermal- and impact-initiated reactions of PTFE/Al energetic materials through ultrasonic-assisted core-shell construction

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Defence Technology（防务技术） 2022年第8期18卷 1362-1368页

作者： Zhou-yang Wu Jin-xu liu Song Zhang xian-qing liu Xiao Xu Wei-zhe Ma Shu-kui li Chuan He School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Science and Technology on Transient Impact Laboratory No.208 Research Institute of China Ordnance Industries102202China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen518172China

A facile and economical approach was developed for the large-scale production of powdered core-shell structured PTFE/Al (CS-PA) energetic materials through ultrasonic-assisted mixing. The low-cost micrometer-sized PTFE and Al particles were used as starting materials. Under high-power ultrasonic waves, the PTFE powder was dispersed into nano-to sub-micrometer-sized particles and then encapsulated the Al microparticles to form the core-shell structure. The heat of combustion, burning rate, and pressurization rate of the powdered CS-PA were measured. The thermal-initiated reaction behavior was further evaluated using thermogravimetry-differential scanning calorimetry. Subsequently, the bulk CS-PA with a uniform microstructure was obtained via cold isostatic pressing of the powdered CS-PA followed by vacuum sintering. For the bulk CS-PA, the quasi-static compression behavior was characterized, and the impact-initiated reaction processes were conducted using the Split Hopkinson Pressure Bar (SHPB) and evaluated by a high-speed camera. Compared to physically mixed PTFE/Al materials, the powdered and bulk CS-PA demonstrated enhanced thermal- and impact-initiated reaction characteristics respectively, proving the effectiveness of our approach for constructing core-shell structures.

关键词： PTFE/Al Core-shell structure Energetic materials Ultrasonic-assisted mixing