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Two-dimensional piston pump: Principle, design,and testing for aviation fuel pumps

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Chinese Journal of Aeronautics 2020年第4期33卷 1349-1360页

作者： Tong XING Yezhou XU Jian ruan Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education Zhejiang University of TechnologyHangzhou 310018China The State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310027China

Aviation fuel pumps of the future are required to be highly efficient and *** such,this work presents the designs of various mechanisms and structures of advanced twodimensional piston pumps for aero-engines,and their universal kinematic design methods are detailed *** efficiency of various piston pump prototypes was experimentally tested at various speeds in an open *** experimental results indicate that two-dimensional piston pumps have a volumetric efficiency>91%and a higher power–mass ratio than conventional fuel pumps under all the conditions ***,the structural and material problems encountered during testing can provide a blueprint for further improvement of the design and processing of two-dimensional piston fuel pumps.

关键词： Fuel pumps Kinematics–design Mechanical design Structure design Two-dimensional piston pumps

H_(2)-Assistance One-Step Growth of Si Nanowires and Their Growth Mechanism

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Chinese Physics Letters 2011年第10期28卷 173-175页

作者： QIU Ming-Xia ruan Shuang-Chen GAO Biao huo Kai-Fu ZHAI Jian-Pang LI Ling LIAO Hui XU Xin-Tong Shenzhen Key Laboratory of Laser Engineering College of Electronic Science and TechnologyShenzhen UniversityShenzhen 518060 College of Materials and Metallurgy Wuhan University of Science and TechnologyWuhan 430081

Large-scale nanowires are grown on Si wafers by the catalyst-free one-step thermal reaction method in Ar/H_(2) mixture atmosphere at 1000°*** x−ray diffraction and energy dispersive x-ray spectroscopy results reveal that the final nanowires are of silicon *** field emission scanning electron microscopy shows that these self-organized Si nanowires(SiNWs)possess curly crowns with diameters varying from 10 to 300 nm and lengths of up to several hundreds of *** transmission electron microscopy indicates that the nanowires are pure Si with amorphous *** the measurement results show that no silicon oxide is generated in our *** growth mechanism is proposed *** oxide is reduced into Si nanoparticles under the Ar/H_(2) mixture,which is the main reason for the formation of such *** experiments offer a method of preparing Si nanostructures by simply reducing silicon oxide at high temperature.

关键词： nanowires preparing hundreds

Anti-hemorrhoidal activity of Lian-Zhi-San,a traditional Chinese medicine,in an experimental hemorrhoidal model in rats

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Journal of Integrative Medicine 2021年第1期19卷 42-49页

作者： Hua Zhang Xiang-yang Yao Dan-feng Zhang Qi-le Guo jun-jun Yang Bao-guo Zhu Dong-xiao Shen Ke-feng ruan Yuan Wang jun-liang Peng Anorectal Department Shanghai Jinshan TCM-Integrated HospitalShanghai 201501China Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Zhangjiang Engineering Research Center of Modern Preparations of TCM Shanghai 201203China

Objective:Hemorrhoidal disease(HD)is the most common proctological disease,with an estimated prevalence rate of 4.4%,and a peak in individuals between 45 and 65 years of *** study was done to evaluate whether Lian-Zhi-San(LZS),a clinically used anti-hemorrhoidal ointment could alleviate the inflammatory injury,with its associated changes of inflammatory cytokines and morphology of anorectal tissues,in an experimental model of HD in ***:HD was induced by croton oil preparation(COP)applied to the anorectal *** were then treated with cotton swabs soaked in LZS ointment,water or white vaseline,twice a day for 7 *** the end of the experiment,HD was evaluated by measuring hemorrhoidal and biochemical parameters along with histopathological ***:In this study,COP induced a significant increase in the macroscopic severity score,anorectal coefficient and Evans blue extravasation,compared to normal ***,it greatly enhanced the expression and secretion levels of some important inflammation-related cytokines along with marked histological damage,compared to normal *** treated with LZS ointment experienced significantly ameliorated Evans blue extravasation(P<0.05),decreased macroscopic severity score(0.86±0.14 vs.1.65±0.16)and the anorectal coefficient(P<0.01);its use also attenuated tissue damage and inhibited the expression and secretion levels of inflammation-related cytokines(interleukin-1 b,interleukin-6 and tumor necrosis factor-a).Conclusion:This study validates a preliminary understanding of the use of LZS ointment to treat inflammatory factors and tissue damage in an experimental model of HD in rats.

关键词： Lian-Zhi-San Hemorrhoidal disease Anti-hemorrhoidal effect Croton oil preparation Berberine hydrochloride

Quasi-Newton-type optimized iterative learning control for discrete linear time invariant systems

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Control Theory and Technology 2015年第3期13卷 256-265页

作者： Yan GENG Xiaoe ruan School of Mathematics and Statistics Xi'an Jiaotong University

In this paper, a quasi-Newton-type optimized iterative learning control （ILC） algorithm is investigated for a class of discrete linear time-invariant systems. The proposed learning algorithm is to update the learning gain matrix by a quasi-Newton-type matrix instead of the inversion of the plant. By means of the mathematical inductive method, the monotone convergence of the proposed algorithm is analyzed, which shows that the tracking error monotonously converges to zero after a finite number of iterations. Compared with the existing optimized ILC algorithms, due to the superlinear convergence of quasi-Newton method, the proposed learning law operates with a faster convergent rate and is robust to the ill-condition of the system model, and thus owns a wide range of applications. Numerical simulations demonstrate the validity and effectiveness.

关键词： Iterative learning control optimization quasi-Newton method inverse plant

Performance-based global reliability assessment of a high-rise frame-core tube structure subjected to multi-dimensional stochastic earthquakes

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 395-415页

作者： Liu Zhangjun ruan Xinxin Liu Zixin School of Civil Engineering and Architecture Wuhan Institute of TechnologyWuhan 430074China Key Laboratory of Building Collapse Mechanism and Disaster Prevention Institute of Disaster PreventionChina Earthquake AdministrationSanhe 065201China

When evaluating the seismic safety and reliability of complex engineering structures,it is a critical problem to reasonably consider the randomness and multi-dimensional nature of ground *** this end,a proposed modeling strategy of multi-dimensional stochastic earthquakes is addressed in this *** improved seismic model has several merits that enable it to better provide seismic analyses of ***,at first,the ground motion model is compatible with the design response ***,the evolutionary power spectrum involved in the model and the design response spectrum are constructed accordingly with sufficient consideration of the correlation between different seismic ***,the random function-based dimension-reduction representation is applied,by which seismic modeling is established,with three elementary random *** simulations of multi-dimensional stochastic ground motions in a specific design scenario indicate the effectiveness of the proposed modeling ***,the multi-dimensional seismic response and the global reliability of a high-rise frame-core tube structure is discussed in detail to further illustrate the engineering applicability of the proposed *** analytical investigations demonstrate that the suggested stochastic model of multi-dimensional ground motion is available for accurate seismic response analysis and dynamic reliability assessment of complex engineering structures for performance-based seismic resistance design.

关键词： multi-dimensional stochastic ground motion dimension-reduction representation frame-core tube structure global dynamic reliability performance-based seismic design

Seeking magneto-structural correlations in easily tailored pentagonal bipyramid Dy (Ⅲ) single-ion magnets

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Science China Chemistry 2020年第8期63卷 1066-1074页

作者： Guo-Zhang Huang Ze-Yu ruan Jie-Yu Zheng Yan-Cong Chen Si-Guo Wu jun-Liang Liu Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510275China

Controlling molecular magnetic anisotropy via structural engineering is delicate and fascinating,especially for single-molecule magnets(SMMs).Herein a family of dysprosium single-ion magnets(SIMs)sitting in pentagonal bipyramid geometry have been synthesized with the variable-size terminal ligands and counter anions,through which the subtle coordination geometry of Dy(Ⅲ)can be finely tuned based on the size *** effective energy barrier(Ueff)successfully increases from 439 to 632 K and the magnetic hysteresis temperature(under a 200 Oe/s sweep rate)raises from 11 to 24 *** on the crystal-field theory,a semi-quantitative magneto-structural correlation deduced experimentally for the first time is revealed that the Ueff is linearly proportional to the structural-related value S20 corresponding to the axial coordination bond lengths and the bond *** the evaluation of the remanent magnetization from hysteresis,quantum tunneling of magnetization(QTM)is found to exhibit negative correlation with the structural-related value Stun corresponding to the axial coordination bond angles.

关键词： single-molecule magnets magnetic anisotropy crystal field magneto-structural correlation

Thermal hazard assessment of TKX-50-based melt-cast explosive

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Defence Technology（防务技术） 2022年第9期18卷 1546-1551页

作者： jun-feng Wang Shu-sen Chen Shao-hua Jin Qing-hai Shu Feng-lei Huang Jian ruan Xiao Ma Kun Chen School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijingChina Gansu Yinguang Chemical Industry Group Co.Ltd BaiyinChina

In the present study, thermal hazards of TNT and DNAN used as the molten binder in TKX-50-based meltcast explosives were comparatively studied through accelerating rate calorimeter(ARC) and Cook-off experiments. Two kinds of ARC operation modes were performed to investigate the thermal safety performance under adiabatic conditions(HWS mode) and constant heating(CHR mode). The obtained results demonstrated that at both heating modes, DNAN/TKX-50 outperformed TNT/TKX-50 from the thermal safety point of view. However, the sensitivity to heat of the samples was reverse because of the different heating modes. In addition, the results of thermal hazard assessment obtained from the cookoff experiment complied with ARC analysis which indicated the molten binder TNT replaced by DNAN would reduce the hazard of the TKX-50 melt cast explosive. Furthermore, the results of cook-off experiments also showed that DNAN/TKX-50 outperformed TNT/TKX-50 from the aspect of thermal stability, which was consistent with the result of CHR mode because of the similar heating process.

关键词： Dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50) 2,4-Dinitroanisole(DNAN) Thermal safety performance Accelerating rate calorimeter(ARC) Cook-off

Cavity length below chute aerators

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Science China(Technological Sciences) 2008年第2期51卷 170-178页

作者： WU JianHua ruan ShiPing College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

It is proved that air entrainment is one of the efficient measures dealing with cavi-tation control for the release works of hydropower projects. There are many factors to be considered in designing a chute aerator. One of the most important factors concerns the cavity length below the aerator,which has outstanding effects on air entrainment against cavitation damage. It is crucial to determine reasonable emergence angle for the calculation of the cavity length. In the present paper the overall effects of structural and hydraulic parameters on the emergence angle of the flow from the aerator were analyzed. Four improved expressions of the emer-gence angle with weight coefficient were investigated through experimental data of 68 points observed from 12 aerators of 6 hydropower projects,of both model and prototype,on the basis of error theory. A method to calculate the cavity length be-low aerators was suggested,which considers overall effects of the above men-tioned parameters. Comparison between the method in this paper and the other five methods of calculating the cavity length showed that the present method is much more reliable than the existing methods while the mean error of the method is less than others.

关键词： aerator air entrainment cavitation damage cavity length emergence angle flow depth transverse fluctua-ting velocity

Janus(BNNS/ANF)-(AgNWs/ANF)thermal conductivity composite films with superior electromagnetic interference shielding and Joule heating performances

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Nano Research 2022年第5期15卷 4747-4755页

作者： Yixin Han Kunpeng ruan junwei Gu Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Highly thermal conductivity materials with excellent electromagnetic interference shielding and Joule heating performances are ideal for thermal management in the next generation of communication industry,artificial intelligence and wearable *** this work,silver nanowires(AgNWs)are prepared using silver nitrate as the silver source and ethylene glycol as the solvent and reducing agent,and boron nitride(BN)is performed to prepare BN nanosheets(BNNS)with the help of isopropyl alcohol and ultrasonication-assisted peeling method,which are compounded with aramid nanofibers(ANF)prepared by chemical dissociation,respectively,and the(BNNS/ANF)-(AgNWs/ANF)thermal conductivity and electromagnetic interference shielding composite films with Janus structures are prepared by the"vacuum-assisted filtration and hot-pressing"***(BNNS/ANF)-(AgNWs/ANF)composite films exhibit"one side insulating,one side conducting"performance,the surface resistivity of the BNNS/ANF surface is 4.7×10^(13) Ω,while the conductivity of the AgNWs/ANF surface is 5,275 S/*** Janus(BNNS/ANF)-(AgNWs/ANF)composite film with thickness of 95 pm has a high in-plane thermal conductivity coefficient of 8.12 W/(m·K)and superior electromagnetic interference shielding effectiveness of 70 *** obtained composite film also has excellent tensile strength of 122.9 MPa and tensile modulus and 2.7 *** also has good temperature-voltage response characteristics(high Joule heating temperature at low supply voltage(5 V,215.0℃),fast response time(10 s)),excellent electrical stability and reliability(stable and constant real-time relative resistance under up to 300 cycles and 1,500 s of tensile-bending fatigue work tests).

关键词： thermal conductivity composite film Janus structure aramid nanofibers electromagnetic interference shielding performance Joule heating