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云母钛珠光颜料的研究进展和发展前景

涂料工业 2003年第7期33卷 31-34页

作者：韩德强钟盛文南方冶金学院材料与化工学院江西赣州341000

综述了云母钛珠光颜料的发展概况和技术动态 ,并阐述了云母钛珠光颜料的制备工艺及形成机理。

关键词：云母钛珠光颜料研究进展发展前景制备工艺机理

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利用单摆测重力加速度时的最大摆角的再讨论

物理实验 2003年第7期23卷 44-45,48页

作者：易德文盛忠志中南林学院物理教研室湖南株洲412006

根据误差传递理论和误差合成方法确定了单摆测重力加速度时的最大摆角 .

关键词：单摆重力加速度最大摆角误差传递理论误差合成方法测量简谐振动振动周期

Numerical simulations of propeller cavitation flows based on OpenFOAM

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Journal of Hydrodynamics 2020年第6期32卷 1071-1079页

作者： Min-sheng Zhao Wei-wen Zhao de-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) State Key Laboratory of Ocean EngineeringSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

In order to study the cavitation and hydrodynamic characteristics of propeller under uniform and non-uniform flows,numerical investigations are performed using interPhaseChangeDyMFoam in the open source computational fluid dynamics(CFD)software platform OpenFOAM with Schnerr-Sauer cavitation *** simulation results can be used as a reference to evaluate the working ability of a propeller in case of actual navigation.A new grid encryption method is adopted in the research to better capture the existence of vortex cavitation at the propeller *** method of function input is carried out in the study to simulate the condition of non-uniform flow and reduce the calculation *** unsteady dynamics are predicted by the Reynolds-averaged Navier-Stokes(RANS)method with a modified shear stress transport(SST)k−ωturbulence *** numerical results of the propeller such as cavitation shape and pressure distribution under uniform and non-uniform flow are analyzed and compared with each other.

关键词： OpenFOAM E779A propeller cavitation non uniform flow

Synthesis of 1,7-dimethoxy-2-hydroxyxanthone,a natural product with potential activity on erectile dysfunction

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Chinese Chemical Letters 2013年第6期24卷 515-517页

作者： wen-Jing Liu de-sheng Mei wen-Hu Duan School of Pharmacy East China University of Science and Technology department of Medicinal Chemistry Shanghai Institute of Materia Medica.Chinese Academy of Sciences department of Medicinal Chemistry Shanghai Institute of Materia MedicaChinese Academy of Sciences

The natural product,1,7-dimethoxy-2-hydroxyxanthone（1）,isolated from Securidaca inappendiculate Hassk,has a potential in the treatment of erectile dysfunction due to its significant relaxation activity on rabbit Corpus ***,the isolation of compound 1 is problematic because of its high similarity in structure to its *** this paper,the first synthesis of 1 was reported featuring two key reactions：a copper-catalyzed coupling reaction and an intramolecular cyclization.

关键词： 1 7-Dimethoxy-2-hydroxyxanthone Erectile dysfunction Synthesis Copper-catalyzed coupling reaction

Applications of Liutex-based force field models for cavitation simulation

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Journal of Hydrodynamics 2021年第3期33卷 488-493页

作者： Min-sheng Zhao Wei-wen Zhao de-cheng Wan Yi-qian Wang Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Ocean College Zhejiang UniversityZhoushan316021China School of Mathematical Science Soochow UniversitySuzhou215006China

When studying the flow dynamics and the characteristics of fluid motion,vortex structure with their interactions is the key *** the present work,a vortex control method is investigated based on the vortex identification system of *** numerical study is carried out in OpenFOAM by directly adding a source term to the Navier-Stokes equations,which is called the centripetal force model in Liutex method.A 2-D test case is examined to justify the proposed method in cavitating flow around Clark-Y hydrofoil,the simulation results show that the improved Liutex solver is *** of controlling the rotation strength of vortices are able to change the flow field and suppress the *** applicability of vortex-based control method in 3-D flow field is also *** results show that cavitation surrounded by particular vortex can be effectively influenced.

关键词： Liutex force model cavitation vortex control

Asymptotic Distributions for Power Variation of the Solution to a Stochastic Heat Equation

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Acta Mathematica Sinica,English Series 2021年第9期37卷 1367-1383页

作者： wen sheng WANG School of Economics Hangzhou Dianzi UniversityHangzhou 310018P.R.China

Let u={u(t,x),t∈[0,T],x∈R}be a solution to a stochastic heat equation driven by a space-time white *** study that the realized power variation of the process u with respect to the time,properly normalized,has Gaussian asymptotic *** particular,we study the realized power variation of the process u with respect to the time converges weakly to Brownian motion.

关键词： Quadratic variation power variation stochastic heat equation weak convergence

Position/Force Hybrid Control System for High Precision Aligning of Small Gripper to Ring Object

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International Journal of Automation and computing 2013年第4期10卷 360-367页

作者： Juan Zhang de Xu Zheng-Tao Zhang wen-sheng Zhang Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences

A position/force hybrid control system based on impedance control scheme is designed to align a small gripper to a special ring object. The vision information provided by microscope vision system is used as the feedback to indicate the position relationship between the gripper and the ring object. Multiple image features of the gripper and the ring object are extracted to estimate the relative positions between them. The end-effector of the gripper is tracked using the extracted features to keep the gripper moving in the field of view. The force information from the force sensor serves as the feedback to ensure that the contact force between the gripper and the ring object is limited in a small safe range. Experimental results verify the effectiveness of the proposed control strategy.

关键词： Feature extraction position/force hybrid control movement control microscope vision micro-assembly.

High-gain and low-distortion Brillouin amplification based on pump multi-frequency intensity modulation

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Chinese Physics B 2019年第2期28卷 277-282页

作者： Li-wen sheng de-Xin Ba Zhi-Wei Lv National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of Technology

Using a pump with a multi-line spectrum to broaden the Brillouin gain bandwidth is an effective way to achieve lowdistortion amplification with high gain. Here, we theoretically and experimentally investigate the generation of a broadband Brillouin gain spectrum based on multi-frequency intensity modulation in an optical fiber. The arbitrary bandwidth of the Brillouin gain spectrum of stimulated Brillouin scattering(SBS) can be obtained as expected. In our experiment, a broadband Brillouin gain spectrum with a bandwidth of about 200 MHz is demonstrated. We also achieve a low-distortion amplification of a weak signal, whose maximum magnification is 65 d B for a-68-dBm input power signal.

关键词： Brillouin gain spectrum bandwidth intensity modulation low distortion amplification

Electronic Properties of a Phenylacetylene Molecular Junction with Dithiocarboxylate Anchoring Group

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Chinese Physics Letters 2013年第1期30卷 172-175页

作者： LIU wen XIA Cai-Juan LIU de-sheng Physics and Information Engineering department Jining UniversityQufu 273155 School of Science Xi'an Polytechnic UniversityXi'an 710048 School of Physics Shandong UniversityJinan 250100

The electronic transport properties of a kind of phenylacetylene compound(4-mercaptophenyl)-phenylacetylene(MPPA)are studied by the first-principles method.A dithiocarboxylate conjugated linker(–CS_(2))is used to anchor the molecule to one gold *** behavior is observed,which is mainly brought about by the asymmetrical coupling of electrodes to the *** is a drastic increase in current as the electrode-electrode distance is reduced,and the rectification ratio increases by 40%as the electrode-electrode distance is diminished from 16Åto 15.7Å.For comparison,we also perform simulations with the–CS_(2) linker replaced by thiol *** shows an obvious reduction in *** find that the stronger interface coupling induced by the–CS_(2) linker broadens transmission resonances near the Fermi energy,which leads to the current enhancement of the molecular junction with–CS_(2) linker.

关键词： method. electrode acetylene