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基于可调双稳态机构的刚柔耦合多模态抓手

机器人 2025年第1期47卷 22-31页

作者：项升张炜韦中杨扬孙聪刘振南京信息工程大学江苏南京210044 东北大学辽宁沈阳110819 哈尔滨工业大学机器人技术与系统全国重点实验室黑龙江哈尔滨150080

现有双稳态抓手通常只有单一的抓取、锁定和释放目标物体的工作模式,限制了其应用的灵活性。为此,本文提出了一种基于可调双稳态机构的刚柔耦合多模态抓手。抓手的夹持表面为弹性带,通过带的包裹可以被动适应不同外形的抓取物。支持夹... 详细信息

现有双稳态抓手通常只有单一的抓取、锁定和释放目标物体的工作模式,限制了其应用的灵活性。为此,本文提出了一种基于可调双稳态机构的刚柔耦合多模态抓手。抓手的夹持表面为弹性带,通过带的包裹可以被动适应不同外形的抓取物。支持夹持表面的手指骨架为刚性连杆组成的可调双稳态机构,其通过弹性圈进行储能。抓手还具有一根由离合器控制的主动绳索,可对弹性带进行能量调节。通过协调控制双稳态机构和主动绳索可调节抓手的能量,抓手具有触发跳变关闭、可控抓取和物体弹射等不同工作模态。建立了抓手触发力的解析模型,并通过动力学仿真和实验对设计参数进行分析,优化选取了弹性元件的刚度和自由长度。在不同工作模态下进行了样机实验,实验结果表明从初始状态切换到触发状态时触发力的调节范围为0.1~1.1 N,对直径30 mm、质量10 g的圆柱体的水平弹射距离可达3.35 m。

关键词：双稳态机构多模态抓手刚柔混合机构弹射

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Effect of Halogen Chain End Fidelity on the Synthesis of Poly(methyl methacrylate-b-styrene)by ATRP

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Chinese Journal of Polymer Science 2018年第11期36卷 1217-1224页

作者： Guang-Cheng Huang sheng-xiang Ji Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Beijing 100049China

Poly（methyl methacrylate-b-styrene）（PMMA-b-PS） block copolymers are synthesized by two consecutive ATRPs and fractionated into four fractions. The halogen chain end fidelity （CEF） in PMMA-b-PS is quantified based on the analysis of each fraction. Compared to ethyl 2-phenyl-2-bromoacetate/CuBr/2,2＇-bipyridine （EPBA/CuBr/bpy） and CuBr/N,N,N＇,N＂,N＂-pentamethyldiethylene- triamine （CuBr/PMDETA） catalysts, PMMA-b-PS synthesized using p-toluenesulfonyl chloride/CuCl/bpy （TsC1/CuC1/bpy） and CuC1/PMDETA catalysts has a higher halogen CEF and a better control on molecular weight.

关键词： Atom transfer radical polymerization Chain end fidelity Block copolymer

Effect of Ink Molecular Weights and Annealing Conditions on Molecular Transfer Printing

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Chinese Journal of Polymer Science 2018年第6期36卷 697-702页

作者： Yuan-Yuan Pang sheng-xiang Ji Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Beijing 100049China

The molecular transfer printing（MTP） technique has been invented to fabricate chemical patterns with high fidelity using homopolymer inks. In this work, we systematically studied the effects of the molecular weights of homopolymer inks and transfer conditions on the MTP process. We explored a large range of molecular weights（~3.5-56 kg·mol^（-1）） of hydroxyl-terminated polystyrene（PS-OH） and hydroxyl-terminated poly（methyl methacrylate）（PMMA-OH） in the MTP process, and found that the resulting chemical patterns on replicas from all five blends were functional and able to direct the assembly of films of the same blends. The transfer temperature and the film annealing sequences had an impact on the MTP process. MTP was sensitive to the transfer temperature and could only be performed within a certain temperature range, i.e. higher than the glass transition temperature（T_g） of copolymers and lower than the rearrangement temperature of the assembled domains. Pre-organization of the blend films was also necessary for MTP since the preferential wetting of PMMA domains at the replica surface might result in the formation of a PMMA wetting layer to prevent the presentation of underlying chemical patterns to the replica surface.

关键词： Block copolymer Molecular transfer printing Thermal annealing Chemical pattern Directed self-assembly

An Improved Time Domain Approach for Analysis of Floating Bridges Based on Dynamic Finite Element Method and State-Space Model

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China Ocean Engineering 2022年第5期36卷 682-696页

作者： xiang sheng CHENG Bin ZHANG Feng-yu TANG Miao State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Civil Engineering Fuzhou UniversityFuzhou 350108China

The floating bridge bears the dead weight and live load with buoyancy,and has wide application prospect in deep-water transportation *** structural analysis of floating bridge is challenging due to the complicated fluid-solid coupling effects of wind and *** this research,a novel time domain approach combining dynamic finite element method and state-space model(SSM)is established for the refined analysis of floating *** dynamic coupled effects induced by wave excitation load,radiation load and buffeting load are carefully ***-precision fitted SSMs for pontoons are established to enhance the calculation efficiency of hydrodynamic radiation forces in time *** dispersion relation is also introduced in the analysis model to appropriately consider the phase differences of wave loads on *** proposed approach is then employed to simulate the dynamic responses of a scaled floating bridge model which has been tested under real wind and wave loads in *** numerical results are found to agree well with the test data regarding the structural responses of floating bridge under the considered environmental *** proposed time domain approach is considered to be accurate and effective in simulating the structural behaviors of floating bridge under typical environmental conditions.

关键词： floating bridge time domain analysis dynamic analysis state-space model environmental load

Personalized image-based templates for precise acetabular prosthesis placement in total hip arthroplasty:a pilot study

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 673-680页

作者： Bin CHEN sheng-xiang XIAO Peng-cheng GU xiang-jin LIN Department of Orthopaedics the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective：In order to achieve accurate implantation of the acetabular prosthesis in total hip arthroplasty（THA）,we designed individual templates based on a three-dimensional（3D） model generated from computed tomography（CT） ***：Individual templates were designed for 12 patients who underwent THA.A physical template was designed to conform to the contours of the patient＇s acetabulum and to confirm the rotation of the acetabular *** guided the acetabular component ***：The preoperative and postoperative X-ray and CT scans were obtained to assess the location with respect to the accuracy of the acetabular *** all patients,the abduction angle of the acetabular component was 46.7°to 54.3°and the anteversion angle was 11.3°to 18.5°Conclusions：The assessment of postoperative CT scans demonstrated higher accuracy of the acetabular component bore when used with the individual ***,the individual template can be an alternative to the computer-assisted navigation systems,with a good cost-performance ratio.

关键词： Total hip arthroplasty Templates Acetabular prosthesis

Synthesis and Crystal Structure of a New Glycinato Copper Compound

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Chinese Journal of Structural Chemistry 2006年第5期25卷 631-635页

作者： xiang sheng-Chang sheng Tian-Lu FU Rui-Biao HU sheng-Min WU Xin-Tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A glycinato copper compound {Cu（NH2CH2COO）（H2O）ClO4} crystallizes in monoclinic, space group P21/n with a = 7.8299（9）, b = 10.3807（10）, c = 9.4775（12）A, β = 109.659（6）°, V = 725.43（12）A^3, Z = 4, Mr = 255.07, Dc = 2.335 g/cm^3, F（000） = 508,μ = 3.381 mm^-1, R = 0.0270 and wR = 0.0707 for 1677 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The title compound contains a chain in the syn-anti conformation, which is generated by the glide-plane operation. The adjacent layers made up of the chains through the connection of perchlorate are related by inversion center operation, which links with each other through the hydrogen bonds.

关键词： glycinato copper complex chain hydrogen bonds

Assessment of Operational Performance in a Power Generation/Selling Integrated Company Using a Dynamic Proportional Adjustment Coefficient

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Energy Engineering 2024年第11期121卷 3263-3287页

作者： Jingbin Wu Hongming Yang sheng xiang Economics and Management College Changsha University of Science and TechnologyChangsha410114China Electrical and Information Engineering College Changsha University of Science and TechnologyChangsha410114China

Currently,the operational performance assessment system in the power market primarily focuses on power generation and electricity retail companies,lacking a system tailored to the operational characteristics of power generation/selling integrated ***,this article proposes an assessment index system for assessing the operational performance of a power generation/selling integrated company,encompassing three dimensions:basic capacity,development potential,and external environment.A dynamic proportional adjustment coefficient is designed,along with a subjective and objective weighting model for assessment indexes based on a combined ***,the operational performance of an integrated company is assessed using extension *** results in the case study demonstrate the feasibility and effectiveness of the proposed dynamic proportional adjustment coefficient.

关键词： Power generation/selling integrated company dynamic proportional adjustment coefficient combined weighting extension theory assessment of operational performance

Varietal Differences in Plant Growth, Phosphorus Uptake and Yield Formation in Two Maize Inbred Lines Grown Under Field Conditions

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Journal of Integrative Agriculture 2012年第10期11卷 1738-1743页

作者： CHEN Fan-jun LIU xiang-sheng MI Guo-hua Key Laboratory of Plant-Soil Interactions Ministry of Education/Center for Resources Environment and Food Security China Agricultural University

Selection for phosphorus （P）-efficient genotypes and investigation of physiological mechanisms for P-use efficiency in maize has mainly been conducted at the seedling stage under controlled greenhouse conditions. Few studies have analyzed characteristics of plant growth and yield formation in response to low-P stress over the whore growth period under field conditions. In the present study, two maize inbred lines with contrasting yield performances under low-P stress in the field were used to compare plant growth, P uptake and translocation, and yield formation. Phosphorus accumulation in the P-efficient line 154 was similar to that of line 153 under high-P. Under low-P, however, P uptake in line 154 was three times greater than that in line 153. Correspondingly, P-efficient line 154 had a significantly higher yield than P-inefficient line 153 under low-P conditions （Olsen-P=1.60 mg kg-1）, but not under high-P conditions （Olsen-P=14.98 mg kg-1）. The yield difference was mainly due to differences in the number of ears per m2, that is, P-efficient line 154 formed many more ears under low-P conditions than P-inefficient line 153. Ear abortion rate was 53% in the P-inefficient line 153, while in line 154, it was only 30%. Low-P stress reduced leaf appearance, and delayed anthesis and the silking stage, but increased the anthesis-silking interval （ASI） to a similar extent in both lines. The maximum leaf area per plant at silking stage was higher in P-efficient line 154 than in P-inefficient line 153 under both P conditions. It is concluded that low-P stress causes intense intraspecific competition for limited P resources in the field condition which gives rise to plant-to- plant non-uniformity, resulting in a higher proportion of barren plants. As soon as an ear was formed in the plant, P in the plant is efficiently reutilized for kernel development.

关键词： ear abortion leaf growth low phosphorus maize phosphorus uptake

Fabrication and luminescent properties of Eu(BMPPA)3BPy complex and its functionalized silica nanocomposites

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Chinese Chemical Letters 2016年第10期27卷 1602-1606页

作者： Hong-xiang Huang Wen-Li He xiang-Hai sheng wen-Jie wu Department of Macromolecular Science and State Key Laboratory of Molecular Engineering of Polymers Shanghai 200433China Department of Chemistry Fudan UniversityShanghai 200423China

Luminescent silica nanocomposites functionalized with a Eu-complex have been prepared and characterized. The europium complex is composed of 2,2＇-bipyridyl （BPy） and 2-（4-bromomethyl）- phenylpropionic acid （BMPPA）, which contains highly active benzyl bromide substituents and can covalently bind with poly（4-vinylpyridine）（P4VP）-modified silica nanoparticles （nanoSiO2P4VP） to form nanoSiO2P4VPEuBIy composites. Microscopic images revealed that the nanoSiO2P4VPEuBPy composites easily formed aggregates, due to an inter-particle binding caused by the benzyl bromide among the composites. The as-prepared nanocomposites showed the typical emissions of Eu（III） ions at the wavelengths from 580 nm to 750 nm designated to the SDo- 7Fn transitions. Time-resolved fluorescence decay measurements revealed that the emission lifetime was approximately 0.204 ms and 0.5？6 ms for the nanoSiO2EuBPy composites, a little shorter than that in the Eu（BMPPA）3BPy complex.

关键词： Eu-complexNanocompositesSilica nanoparticlesFluorescence