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Analysis and control of the compaction force in the composite prepreg tape winding process for rocket motor nozzles

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Chinese Journal of Aeronautics 2017年第2期30卷 836-845页

作者： He Xiaodong shi Yaoyao Kang Chao yu tao School of Mechanical Engineering Northwestern Polytechnical University Xi'an 710072 China

In the process of composite prepreg tape winding,the compaction force could influence the quality of winding *** to the analysis and experiments,during the winding process of a rocket motor nozzle aft exit cone with a winding angle,there would be an error between the deposition speed of tape layers and the feeding speed of the compaction roller,which could influence the compaction *** a lack of compaction and overcompaction related to the feeding of the compaction roller could result in defects of winding ***,a flexible winding system has been developed for rocket motor nozzle *** the system,feeding of the compaction roller could be adjusted in real time to achieve an invariable compaction *** to experiments,the force deformation model of the winding tape is a time-varying ***,a forgetting factor recursive least square based parameter estimation proportional-integral-differential（PID）controller has been developed,which could estimate the time-varying parameter and control the compaction force by adjusting the feeding of the compaction roller during the winding *** to the experimental results,a winding nozzle with fewer voids and a smooth surface could be wounded by the invariable compaction force in the flexible winding system.

关键词： Compaction Composite material Rocket nozzles Parameter estimation Voids Winding processes

Application and prospective of 3D printing in rock mechanics: A review

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 1-17页

作者： Yong-tao Gao Tian-hua wu yu Zhou Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

This review aims to discuss the application and development of three-dimensional printing(3DP) technology in the field of rock mechanics and the mechanical behaviors of 3D-printed specimens on the basis of various available printing *** review begins with a brief description of the concepts and principles associated with 3DP, and then systematically elaborates the five major applications of 3DP technology in the field of rock mechanics, namely, the preparation of rock(including pre-flawed rock) specimens, preparation of joints, preparation of geophysical models, reconstruction of complex rock structures, and performance of bridging experimental testing and numerical ***, the mechanical performance of 3D-printed specimens created using six different printing materials, such as polymers, resin,gypsum, sand, ceramics, and rock-like geological materials, is reviewed in ***, some improvements that can make these 3D-printed specimens close to natural rocks and some limitations of 3DP technology in the application of rock mechanics are *** prospects that are required to be investigated in the future are also ***, a brief summary is *** review suggests that 3DP technology, especially when integrated with other advanced technologies, such as computed tomography scanning and 3D scanning, has great potential in rock mechanics field.

关键词： three-dimensional printing(3DP) rock mechanics 3DP material rock analogue 3DP geotechnical model numerical simulation

Tadpole Diagrams and Relativistic Hartree Approximation

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Chinese Physics Letters 1996年第4期13卷 261-264页

作者： wu shi-shu YAO yu-jie Research Center for Theoretical Physics Department of PhysicsJilin UniversityChangchun 130023

It is pointed out that the infinite series of the tadpole contribution to the baryon self-energy can be summed rigorously and expressed in a simple *** latter provides a new way for the calculation and explains more c... 详细信息

关键词： form Hartree Approximation

Application of focused laser differential interferometer to hypersonic boundary-layer instability study

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Chinese Journal of Aeronautics 2021年第5期34卷 17-26页

作者： tao yu Youde XIONG Jiaquan ZHAO Jie wu School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment Wuhan 430074China

Accurate prediction of hypersonic boundary-layer transition plays an important role in thermal protection system design of hypersonic *** by the capability of spatial diagnostics for hypersonic boundary-layer study,quite a lot of problems of hypersonic boundary-layer transition,such as nonlinearity and receptivity,remain *** work reports the application of focused laser differential interferometer to instability wave development across hypersonic boundary-layer on a flared cone *** begin with,the focused laser differential interferometer is designed and set up in a Mach number 6 hypersonic quiet wind tunnel with the focal point in the laminar boundary-layer of a 5 degree half-angle flared cone ***,instability experiments are carried out by traversing the focal point throughout the hypersonic boundary-layer and the density fluctuation along the boundary-layer profile is measured and *** results show that three types of instability waves ranging from 10 k Hz to over 1 MHz are co-existing in the hypersonic boundary-layer,indicating the powerful capability of focused laser differential interferometer in dynamic response resolution for instability wave study in hypersonic flow regime;furthermore,quantitative analyses including spectra and bicoherence analysis of instability waves throughout the hypersonic boundary-layer for both cold and heated cone models are performed.

关键词： Bicoherence analysis Focused laser differential interferometer Hypersonic boundary-layer instability Non-intrusive measurement Wind tunnel experiment

Concept of Excessive Mesons in Nuclei

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Chinese Physics Letters 1996年第5期13卷 347-350页

作者： wu shi-shu YAO yu-jie Research Center for Theoretical Physics Department of PhysicsJilin UniversityChangchun 130023

The concept of excessive mesons in nuclei is *** nucleons are identical particles,it is pointed out that the physical content of a meson distribution around a bound nucleon in nuclei is different from that of a meson clotid around a free nucleon,if the effect of the principle of identity cannot be *** difference is enunciated in detail.

关键词： meson neglected identical

Probabilistic Teleportation of Three-Atom State via Five-Atom Cluster State

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Communications in Theoretical Physics 2013年第6期59卷 700-702页

作者： yu Li-Zhi wu tao Department of Physics Fuyang Teachers College Fuyang 236041 China Department of Physics Anhui University Hefei 23000 China

A scheme for probabilistic teleportation of an unknown three-atom entangled state via a five-atom non- maximally entangled cluster state as quantum channel is proposed. In this scheme, the sender performs two Bell state and a single-atom measurements on the atoms, the receiver can reconstruct the original state with a certain probability by introducing an auxiliary atom and operating appropriate unitary transformations and controlled-not （C-not） operations according to the sender Alice＇s measurement results. As a result, the probability of successful teleportation is determined by the smallest two of the coefficients＇ absolute values of the cluster state. The considerable advantage of our scheme is that we employ a non-maximally entangled cluster state as quantum channel in the scheme, which can greatly reduce the amount of entanglement resources and need less classical bits. If we employ a maximally entangled cluster state as quantum channel, the probabilistic teleportation scheme becomes usual teleportation, the successful probability being 100%.

关键词： quantum teleportation five-atom cluster state Bell state measurement unitary transformation C-not operation

Porous core–shell CoMn_2O_4 microspheres as anode of lithium ion battery with excellent performances and their conversion reaction mechanism investigated by XAFS

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Journal of Energy Chemistry 2018年第6期27卷 1637-1643页

作者： Hang Su yue-Feng Xu Shou-yu Shen Jian-Oiang wang Jun-tao Li Ling Huang shi-Gang Sun College of Energy School of Energy Research Xiamen UniversityXiamen 361005FujianChina College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005FujianChina Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China

Porous core-shell CoMn204 microspheres of ca. 3-5μm in diameter were synthesized and served as an-ode of lithium ion battery. Results demonstrate that the as-synthesized CoMn204 materials exhibit excel-lent electrochemical properties. The CoMn204 anode can deliver a large capacity of 1070 mAh g-1 in thefirst discharge, a reversible capacity of 500 mAh g^-1 after 100 cycles with a coulombic efficiency of 98.5% at a charge-discharge current density of 200 mA g^-l, and a specific capacity of 385 mAh g^-1 at a muchhigher charge-discharge current density of 1600mA g^-1. Synchrotron X-ray absorption fine structure（XAFS） techniques were applied to investigate the conversion reaction mechanism of the CoMn204 *** X-ray absorption near edge structure （XANES） spectra revealed that, in the first discharge-charge cy-cle, Co and Mn in CoMn204 were reduced to metallic Co and Mn when the electrode was discharged to0.01 V, while they were oxidized respectively to CoO and MnO when the electrode was charged to *** of both XANE5 and extended X-ray absorption fine structure （EXAFS） revealed that neithervalence evolution nor phase transition of the porous core-shell CoMn204 microspheres could happen inthe discharge plateau from 0.8 to 0.6V, which demonstrates the formation of solid electrolyte interface（SEI） on the anode.

关键词： Lithium ion battery Porous core-shell CoMn2O4 anode Conversion reaction mechanism XAFS

Effect of modified elastomeric binders on the electrochemical properties of silicon anodes for lithium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 752-756页

作者： tao Li Juan-yu Yang shi-gang Lu General Research Institute for Nonferrous Metals Beijing 100088China

Silicon has been investigated intensively as a promising anode material for rechargeable lithium-ion batteries. The choice of a binder is very important to solve the problem of the large capacity fade observed along cycling. The effect of modified elastomeric binders on the electrochemical performance of crystalline nano-silicon powders was studied. Compared with the conventional binder （polyvinylidene fluoride （PVDF））, Si electrodes using the elastomeric styrene butadiene rubber （SBR） and sodium carboxymethyl cellulose （SCMC） com- bined binder show an improved cycling performance. The reversible capacity of the Si electrode with the SCMC/SBR binder is as high as 2221 mA.h/g for 30 cycles in a voltage window between 0.005 and 2 V. The structure changes from SEM images of the silicon electrodes with different binders were used to explore the property improvement.

关键词： lithium batteries silicon anodes electrochemical properties

Analysis of the Electrophoretic Profiles of Prion Protein in Carcinous and Pericarcinous Lysates of Six Different Types of Cancers

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Biomedical and Environmental Sciences 2021年第9期34卷 683-692页

作者： WEI Wei wu yue Zhang XIAO Kang XU Guo Hui SONG yun tao shi Qi DONG Xiao Ping Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education) Head and Neck Surgery DepartmentPeking University Cancer Hospital&InstituteBeijing 100142China State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases(Zhejiang University)National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Center for Global Public Health Chinese Center for Disease Control and PreventionBeijing 102206China wuhan Institute of Virology Chinese Academy of ScienceWuhan 430071Hubei China China Academy of Chinese Medical Sciences Beijing 100700China

Objective To find the different electrophoretic profiles of prion protein in carcinous and individual pericarcinous tissues in lysates of gastric,colon,liver,lung,thyroid,and laryngeal *** Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)and Western blot were used to test the amounts and electrophoretic patterns of total Pr P and the tolerance of PK(protease K)digestion among six various cancer tissue *** A mass of Pr P signals with a large molecular weight were identified in the homogenates of peripheral *** amounts and electrophoretic patterns of total Pr P did not differ significantly between carcinous and pericarcinous *** Ps in all types of the tested cancer samples were PK sensitive but showed diversity in the tolerance of PK digestion among various tissue *** The study revealed that the included electrophoretic patterns of carcinous and pericarcinous tissues were almost *** Pr P-specific immunohistochemical assay,evaluation of Pr P electrophoretic patterns in the peripheral organs and tissues by Western blot does not reflect tumor malignancy.

关键词： Prion protein Cancer Electrophoretic profiles