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Journal of Materiomics 2024年第2期10卷 463-470页

作者： Xin pei Wenfei Wei Gang he Xinjiang Institute of Technology Xinjiang843100China Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430074China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXiningQinghai810008China

The rational design of green chemical,low-cost,and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and ultralong cycle life Li-metal ***,a homogeneous composite solid polymer electrolyte(CSPE)is fabricated with water as the ideal dispersion medium,hectorite(Ht)as nanofiller,and poly(ethylene oxide)(PEO)as the matrix,to guide uniform Li plating/*** from the merit of Ht can form uniformly dispersed nanosheets in water,the obtained CSPE inheres to a low melting point,robust mechanical property,and high Li^(+)transference ***,the fabricated Li symmetric battery using PEO-Ht-LiClO_(4)CSPE keeps cycling steadily for 4000 *** well demonstrated water-based CSPE paves the way for developing low-cost,environmentally friendly,and safe solid-state electrolytes for Li-metal batteries.

关键词： Water Solid-state electrolytes Homogeneous hectorite Li-metal battery

Dynamic Analysis and Optimization of Pneumatic Wedge-Shaped Launcher for UAV

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第5期35卷 866-873页

作者： Huang Min he Cheng pei Jinhua College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Key Laboratory of UAV’s Advanced Technology(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information Technology

The constitution,structure,working principle and launching process of the wedge-shaped pneumatic launcher of an unmanned aerial vehicle(UAV)are *** simplifying its physical model,two dynamic models of the UAV launch system are established based on Lagrange equation and ***,*** curves of the acceleration and the velocity of UAV changing with time are *** simulation results are compared with the experimental results to verify the correctness of the ***,the influence of the parameters on the launch is ***,the system is *** maximum overload and the acceleration fluctuation are reduced.

关键词： unmanned aerial vehicle pneumatic launching dynamic simulation system optimization

Multi-objective Optimization Design of Vented Cylindrical Airbag Cushioning System for Unmanned Aerial Vehicle

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第2期33卷 208-214页

作者： Shao Zhijian he Cheng pei Jinhua Research Institute of Pilotless Aircraft Nanjing University of Aeronautics and Astronautics

Multi-objective optimization design of the gas-filled bag cushion landing system is ***,the landing process of airbag is decomposed into a adiabatic compression and a release of landing shock energy,and the differential equation of cylindrical gas-filled bag is presented from a theoretical perspective based on the ideal gas state equation and dynamic ***,the effects of exhaust areas and blasting pressure on buffer characteristics are studied,taking those parameters as design variable for the multiobjective optimization problem,and the solution can be determined by comparing Pareto set,which is gained by NSGA-Ⅱ.Finally,the feasibility of the design scheme is verified by experimental results of the ground test.

关键词： airbag vent orifice soft landing multi-objective optimization unmanned aerial vehicle (UAV)

Investigation of the Short-Time Photodissociation Dynamics of Furfural in S2 State by Resonance Raman and Quantum Chemistry Calculations

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Computers, Materials & Continua 2018年第4期55卷 189-200页

作者： Kemei pei Yueben dong Lei Chen Department of Chemistry Zhejiang Science Techology UniversityHangzhou 310018China

Raman(resonance Raman,FT-Raman),IR and UV-visible spectroscopy and quantum chemistry calculations were used to investigate the photodissociation dynamics of furfural in S2 *** resonance Raman(RR)spectra indicate that the photorelaxation dynamics for the S0→S2 excited state is predominantly along nine motions:C=O stretchν5(1667 cm-1),ring C=C antisymmetric stretchν6(1570 cm-1),ring C=C symmetric stretchν7(1472 cm-1),C2-O6-C5 symmetric stretch/C1-H8 rock in planeν8(1389 cm-1),C3-C4 stretch/C1-H8 rock in planeν9(1370 cm-1),C5-O6 stretch in planeν12(1154 cm-1),ring breathν13(1077 cm-1),C3-C4 stretchν14(1020 cm-1),C3-C2-O6 symmetric stretchν16(928 cm-1).Stable structures of S0,S1,S2,T1 and T2 states with Cs point group were optimized at CASSCF method in Franck-Condon region there are S2/S1 conical intersection was found by state average method and RR spectra.

关键词： Furfural resonance Raman quantum chemistry calculation excited state structural dynamics

Influence of the inherent properties of drinking water treatment residuals on their phosphorus adsorption capacities

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Journal of Environmental Sciences 2014年第12期26卷 2397-2405页

作者： Leilei Bai Changhui Wang Liansheng he Yuansheng pei The Key Laboratory of Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University Water Environment System Project Laboratory Chinese Research Academy of Environmental Sciences

Batch experiments were conducted to investigate the phosphorus（P） adsorption and desorption on five drinking water treatment residuals（WTRs） collected from different regions in China. The physical and chemical characteristics of the five WTRs were determined. Combined with rotated principal component analysis, multiple regression analysis was used to analyze the relationship between the inherent properties of the WTRs and their P adsorption capacities. The results showed that the maximum P adsorption capacities of the five WTRs calculated using the Langmuir isotherm ranged from 4.17 to8.20 mg/g at a p H of 7 and further increased with a decrease in p H. The statistical analysis revealed that a factor related to Al and 200 mmol/L oxalate-extractable Al（Alox） accounted for 36.5% of the variations in the P adsorption. A similar portion（28.5%） was attributed to an integrated factor related to the p H, Fe, 200 mmol/L oxalate-extractable Fe（Feox）, surface area and organic matter（OM） of the WTRs. However, factors related to other properties（Ca,P and 5 mmol/L oxalate-extractable Fe and Al） were rejected. In addition, the quantity of P desorption was limited and had a significant negative correlation with the（Feox＋ Alox） of the WTRs（p 〈 0.05）. Overall, WTRs with high contents of Alox, Feoxand OM as well as large surface areas were proposed to be the best choice for P adsorption in practical applications.

关键词： Adsorption Desorption Drinking water treatment residuals Phosphorus Principal component analysis

Kinetics of recrystallization for twin-roll casting AZ31 magnesium alloy during homogenization

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 570-575页

作者： Hu Zhao pei-jie Li Liang-ju he National Center of Novel Materials for International Research Tsinghua University Beijing 100084 China

The kinetics of recrystallization for twin-roll casting AZ31 magnesium alloy with different thicknesses during homogenization was *** is shown that fine grains are first formed at the boundaries of deformed bands in the twin-roll casting *** recrystallized grains with no strain are gradually substituted for the deformed microstructure of twin-roll casting AZ31 magnesium *** incubation temperature and time for the recrystallization of a twin-roll casting AZ31 magnesium alloy strip with a thickness of 3 mm are lower and shorter than those of the 6-mm thick strip,*** 3-mm thick twin-roll casting magnesium alloy has finer grains than the 6-mm thick *** activation energies of recrystallization for twin-roll casting AZ31 magnesium alloy slabs with the thickness of 3 and 6 mm are 88 and 69 kJ/mol,*** kinetics curves of recrystallization for twin-roll casting AZ31 magnesium alloy were obtained.

关键词： magnesium alloys twin-roll casting homogenization kinetics grain size

Development of S-Band High Power Klystron

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Chinese Journal of Electronics 2020年第4期29卷 772-778页

作者： WANG Shengchang dong dong pei Shilun ZHOU Zusheng FUKUDA Shigeki ZheNG Kai Institute of High Energy Physics Chinese Academy of Sciences High Energy Accelerator Research Organization Hubei Hanguang Technology Co. Ltd

A 2998 MHz, 60 MW klystron has been developed for future linear accelerators of synchrotron radiation *** order to save development and construction time, the 2998 MHz, 60 MW klystron is a modified version of an existing 2856 MHz klystron used in linear accelerator of Beijing Electron-Positron Collider Ⅱ.Based on the simulations, it was shown that the scaled version klystron was able to produce more than 60 MW at a 350 kV beam voltage.A prototype was built and *** successfully produced 50 MW output power with an RF pulse width of 4.0μs, which exceeded the operating requirement of China’s High Energy Photon *** also produced 62 MW with an RF pulse width of 1.6μs, which proved the validity of new RF circuit *** paper describes the details of the progresses of this klystron and advantages of this tube development.

关键词： Klystron Linear accelerator Radio-frequency(RF) source

Enantioselective Chlorocyclization of Olefinic Amides with 1,3-Dichloro-5,5-Dimethylhydantoin（DCDMH） Catalyzed by（DHQD）2PHAL

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Wuhan University Journal of Natural Sciences 2018年第3期23卷 259-264页

作者： ZHOU Qingjun GUO Chao LI Xiwang he pei YANG Guichun dong Chune Hubei Collaborative Innovation Center for Advanced Organochemical Materials & Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Hubei University Wuhan 430062 Hubei China School of Pharmaceutical Sciences Wuhan UniversityWuhan 430071 Hubei China

An efficient catalytic asymmetric chlorocyclization of olefinic amides with 1,3-dichloro-5,5-dimethylhydantoin（DCDMH） using hydroquinidine 1,4-phthalazinediyl diether（（DHQD）_2 PHAL） as organocatalyst has been developed. Series of chiral chloro substituted isobenzofuran-1（3 H）-imine derivatives were obtained in good yields（up to 85%） and enantioselectivities（up to 70% ee）.

关键词： Catalyzed by Dimethylhydantoin Enantioselective Chlorocyclization of Olefinic Amides with 1 3-Dichloro-5 DCDMH

Effect of Air Injector on the Performance of an Air-lift for Conveying River Sand

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 122-128页

作者： TANG Chuanlin HU dong pei Jianghong YANG Lin College of Mechanical Engineering Hunan University of Technology Zhuzhou 412008 China Department of Mechanical Engineering Chongqing Jiaotong University Chongqing 400044 China

An air-lift has been more recently applied in the dredging, deep-seated beach placer mining and underground mining engineering. However, the influence and mechanism of various parameters on the air-lift performance are not quite clear, especially the influence of flow pattern on lifting efficiency. Focusing on the problems mentioned above, the key part of the air-lift （namely, the air injector） was proposed aimed to reduce friction loss in the inner pipe according to improving flow field performance, thus increase the lifting efficiency. The study of relative factors of the performance of an air-lift is performed and the river sand is used as simulation of underground ore bed. The total lifting height of the experimental system is 3 m, the water flux, mass flow of solid particles, concentration of particles and lifting efficiency are measured under the same submergence ratios by changing the air injector, which is divided into nine specifications of air injection in this research. The experimental results indicate that the optimal air flow rate corresponding to excellent performance of the air-lift can be obtained in the range of 35-40 m3/h. The air injection method has a great effect on the performance of the air-lift, the air injector with three nozzles is better than that in the case of one or two nozzles. Further more, the air injection angle and arrangement of air injection pipes also have great effect on the performance of an air-lift. The proposed research results have guiding significance for engineering application.

关键词： air-lift submergence ratio air flow rate air injector lifting efficiency

Wake Vortex Structure Characteristics of a Flexible Oscillating Fin

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Journal of Bionic Engineering 2008年第1期5卷 49-54页

作者： Zhi-dong Wang pei Chen Xiao-qing Zhang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003 P. R.China Det Norske Veritas 1591 Hongqiao Road Shanghai 200336 P. R. China

We compute the wake of a two-dimensional and three-dimensional flexible fin in an unsteady flow field with heaving and pitching motions using FLUENT. Deflexion mode is used for a non-uniform cantilever beam with non-uniformly distributed load. The effect of chordwise deflexion length on the characteristics of propulsion is discussed for two-dimensional flexible fin. The thrust coefficient decreases, propulsive efficiency increases and the intensity of turbulence attenuates gradually as the deflexion length increases. For a three-dimensional flexible fin, the intensity of the vortex in the plane of symmetry is higher than that in the plane at 3/4 span length of the caudal fin. But the propulsive *** achieved is not what we expected with the given deflexion mode.

关键词： flexible fin deflexion length turbulence intensity structure of flow field