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ON CRACK-TIP STRAIA ENERGy RELEASE RATE IN NON-PRINCIPAL DIRECTIONS OF ELASTICITy FOR SIMPLE LAyER PLATE OF COMPOSITE MATERIALS

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Applied Mathematics and Mechanics(English Edition) 1993年第8期14卷 745-752页

作者： yang Wei-yang Zhang shao-qin Taiyuan Heavy Machinery Institute Taiyuan

In this paper,the fracture problem in non-principal directions of elasticity for a simple layer plate of linear-elastic orthotropic composite materials is *** formulae of transformation between characteristic roots,coefficients of elastic compliances in non-principal directions of elasticity and corresponding parameters in principal directions of elasticity are ***,the computing formulae of strain energy release rate under skew-symmetric loading in terms of engineering parameters for principal directions of elasticity are obtained by substituting crack-tip stresses and displacements into the basic formula of the strain energy release rate.

关键词： strain energy release rate non-principal directions of elasticity central through crack skew-symmetric loading orthotropic composites.

ON J-INTEGRALS NEAR MODELSⅠ,ⅡCRACK TIPS IN THE PLATE OF ORTHOTROPIC COMPOSITE MATERIAL

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Applied Mathematics and Mechanics(English Edition) 1990年第7期11卷 687-696页

作者： yang Wei-yang Zhang shao-qin Taiyuan Heavy Machinery Institute Taiyuan

In this paper,we prove the independence of the path of the imegrals near model i II track tips in the plate of the orthotropic composite *** we derive the computing formulae of the J-integrals at the cases of and by using a complex variable method and redueing J-imegrals to compley farm The J-integral computational formulae derived this paper have certain reference value for the theoretical researches and the experimental verifications in the plane fracture for composite material.

关键词： Mechanics

The theory and practice in the evolution of trusted computing

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Chinese Science Bulletin 2014年第32期59卷 4173-4189页

作者： Dengguo Feng yu qin Wei Feng Jianxiong shao Trusted Computing and Information Assurance Laboratory Institute of Software Chinese Academy of Sciences State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences

Trusted computing(TC)is an emerging technology to enhance the security of various computing platforms by a dedicated secure chip(TPM/TCM),which is widely accepted by both the industrial and academic *** paper attempts to sketch the evolution of TC from the view of our theoretical and engineering *** theory,we focus on protocol design and security *** have proposed the first ECDAA protocol scheme based on q-SDH assumption,which highlights a new way to design direct anonymous attestation *** technical evolution,we discuss the key technologies of trust chain,trusted network connection and TC testing and *** break through several key technologies such as trusted boot,OS measurement and remote attestation,and implement a TC system from TPM/TCM to *** also design and implement a testing and evaluation system of TC platform,which is the first one put into practical application in ***,with the rapid development of cloud computing and mobile applications,TC is moving toward some new directions,such as the trust in cloud and mobile environments,new TPM standard,and flexible trust execution environment trust establishment method.

关键词：可信计算 TCM 计算平台移动应用 TPM 安全芯片安全分析匿名认证

Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes

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Frontiers of Environmental Science & Engineering 2013年第1期7卷 66-76页

作者： qin WANG Chunmei GENG Sihua LU Wentai CHEN Min shao State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO2, CO, CH4, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC-FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO2. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.

关键词： residential combustion coal crop residue briquette emission factors gaseous carbonaceous species

Research progress of Pt and Pt-based cathode electrocatalysts for proton-exchange membrane fuel cells

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Chinese Physics B 2022年第12期31卷 619-628页

作者： Ni Suo Longsheng Cao Xiaoping qin Zhigang shao Fuel-Cell System and Engineering Laboratory Key Laboratory of Fuel Cells&Hybrid Power SourcesDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Proton-exchange membrane fuel cells(PEMFCs)have been widely used commercially to solve the energy crisis and environmental *** oxygen reduction reaction(ORR)at the cathode is the rate-determining step in ***(Pt)catalysts are used to accelerate the ORR ***’s scarcity,high cost,and instability in an acidic environment at high potentials seriously hinder the commercialization of ***,studies should explore electrocatalysts with high catalytic activity,enhanced stability,and low-Pt *** review briefly introduces the research progress on Pt and Pt-based ORR electrocatalysts for PEMFCs,including anticorrosion catalyst supports,Pt,and Pt-based alloy *** preparation technology and material characterization of Pt-based ORR electrocatalysts are necessary to improve the performance and corresponding reaction mechanisms.

关键词： electrocatalysts oxygen reduction reaction activity stability

Study of a ceramic burner for shaftless stoves

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 149-153页

作者： Fang-qin Dai Su-yi Huang shao-hua Li Ke Liu School of Energy ＆ Power Engineering Huazhong University of Science and Technology Wuhan 430074 China Thermal Engineering Research Institute Wuhan Research Institute of Metallurgical Construction Wuhan 430081 China

A multi-burner-port annular flameless ceramic burner （MAFCB） of the shaftless stove for blast furnaces was designed. The characteristics of pressure drop, homogeneousness of the flows at burner ports, and distribution of the flows in the chambers and joint were studied by cold model experiments. This type of ceramic burner was successfully applied in 6# blast furnace at Liuzhou Iron ＆ Steel Co. Ltd. （LISC） and this practice proved that it could be used in the hot blast stove and other stoves with a higher efficiency and a higher steadiness of hot blast temperature at 1200℃. With the combustion of blast furnace gas alone, the thermal efficiency was up to 78.95%, saving energy remarkably.

关键词： ceramic burner blast furnace cold model experiments ironmaking

Combustion of Hydrogen in an Experimental Trapped Vortex Combustor

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Journal of Thermal Science 2009年第3期18卷 256-261页

作者： Hui Wu qin Chen Weiwei shao yongliang Zhang yue Wang yunhan Xiao Graduate University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Advanced Energy and Power IET CAS Beijing 100190 China

Combustion performances of pure hydrogen in an experimental trapped vortex combustor have been tested underdifferent operating conditions. Pressure fluctuations, NOx emissions, OH distributions, and LBO (Lean Blow Out)were measured in the tests. Results indicate that the TVC test rig has successfully realized a double vortex constructionin the cavity zone in a wide range of flow conditions. Hydrogen combustion in the test rig has achievedan excellent LBO performance and relatively low NOx emissions. Through comparison of dynamic pressure data,OH fluctuation images, and NOx emissions, the optimal operating condition has been found out to be Φp=0.4,fuel split=0.4, and primary air/fuel premixed.

关键词： trapped vortex combustor hydrogen combustion

One-pot synthesis of Li_3VO_4@C nanofibers by electrospinning with enhanced electrochemical performance for lithium-ion batteries

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Science Bulletin 2017年第15期62卷 1081-1088页

作者： Ruihuan qin Gaoqi shao Junxian Hou Zhi Zheng Tianyou Zhai Huiqiao Li State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology (HUST) Department of Composite Materials and Engineering College of Materials Science and Engineering Hebei University of Engineering

Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphology is still successfully obtained through adjusting different heat treatment processes and different vanadium sources. The prepared Li3VO4@C nanofibers exhibit a unique structure in which nanosized Li3VO4 particles are uniformly embedded in amorphous carbon matrix. Compared with LiBVO4/C powder, Li3VO4@C nanofibers display enhanced reversible capacity of 451 mAhg^-1 at 40mAg^-1 with an increased initial coulombic efficiency of 82.3%, and the capacity can remain at 394 mAh g ^-1 after 100 cycles. This superior electrochemical performance can be attributed to its unique structure which ensures a high reactivity by nanosized Li3VO4, more stable electrode/electrolyte interface by carbon encapsulation, improved electronic conductivity and buffered volume changes by flexible carbon matrix. The electrospinning technology provides an effective method to obtain high performance Li3VO4 as a promising anode material for lithium-ion batteries.

关键词： Lithium vanadium oxide Electrospinning Lithium-ion batteries Anode Carbon nanocomposite

On the solution of Stokes equations for plane boundaries

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Acta Mechanica Sinica 2017年第1期33卷 62-64页

作者： y. qin R. Sun Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

In a recent paper (Li et al., Acta Mech. Sin. 31, 32-44, 2015), the authors claimed that the general solution of steady Stokes flows can be compactly expressed using only two harmonic functions. They present two cases of a flat plate translating through a viscous fluid. The present paper shows that such a two-harmonic solution does not describe the rotation of a circular plate in an unbounded fluid and thus confirms that at least three independent harmonics are required to express the general solution of Stokes equations.

关键词： Stokes flow General solution Harmonics