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Bionic lightweight design of limb leg units for hydraulic quadruped robots by additive manufacturing and topology optimization

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Bio-Design and Manufacturing 2024年第1期7卷 1-13页

作者： Huaizhi Zong Junhui Zhang lei jiang Kun Zhang Jun Shen Zhenyu Lu Ke Wang Yanli Wang Bing Xu The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China Unmanned Vehicle Research and Development center China North Vehicle Research InstituteBeijing 100072China School of Mechatronic Engineering Nanchang UniversityNanchang 330031China Auclean High-Tech Ltd. Wuxi 214108China

Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped *** various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large *** the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight *** by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an *** propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston *** addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the *** mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah *** mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.

关键词： Additive manufacturing Bionic lightweight design Limb leg unit Quadruped robot Trajectory tracking

HYPERBRANCHED AROMATIC POLYMERS OBTAINED VIA SELF-CONDENSATION

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chinese Journal of Polymer Science 2001年第5期19卷 517-520页

作者： Xi Zhang Yong-ming Chen Dong-yan Wang Jing jiang Hong-wei Liu Chuan-fu Chen Fu Xi center for molecular Science, institute of chemistry chinese academy of sciences, beijing 100080, china The State Key Laboratory of Functional Polymer Materials for Adsorption and Separation, Nankai University Tianjin 300071, china 中科院化学所北京南开大学吸附分离功能高分子材料国家重点实验室天津

Hyperbranched aromatic polymers were prepared by Friedel-Crafts reaction with Lewis acid, AlCl3 and ZnCl2, as the catalysts. In this work, hyperbranched polybenzyl (PB) and poly(methylene)naphthalene (PN) were synthesized and characterized by H-1-NMR and GPC. In addition, their florescence properties were measured with steady-state florescence spectra in THF and ethylene dichloride. The quantum yields of polybenzyl and poly(methylene)naphthalene in ethylene dichloride are much larger than those in THE.

关键词： hyperbranched polymer polybenzyl poly(methylene)naphthalene fluorescent spectra

Synthesis and photophysical properties of Ir~Ⅲ-Ln~Ⅲ(Ln=Nd,Yb,Er) bimetallic complexes containing bipyrimidines as bridging ligands

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Science china chemistry 2009年第11期52卷 1808-1813页

作者： CHEN FangFang,jiang WeiLi,LOU Bin,BIAN ZuQiang & HUANG ChunHui beijing National Laboratory for molecular sciences,State Key Laboratory of Rare Earth Materials chemistry and Applications,College of chemistry and molecular Engineering,Peking University,beijing 100871,china beijing National Laboratory for molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing China

Bipyrimidines have been chosen as(N^N)(N^N) bridging ligands for connecting metal ***Ⅲ-LnⅢ(Ln = Nd,Yb,Er) bimetallic complexes [Ir(dfppy)2(μ-bpm)Ln(TTA)3]Cl were synthesized by using Ir(dfppy)2(bpm)Cl as the ligand coordinating to lanthanide complexes Ln(TTA)3·*** stability constants between Ir(dfppy)2(bpm)Cl and lanthanide ions were measured by fluorescence *** obvious quenching of visible emission from IrⅢ complex in the IrⅢ-LnⅢ(Ln = Nd,Yb,Er) bimetallic complexes indicates that energy transfer occurred from IrⅢ center to *** emissions from NdⅢ,YbⅢ,and ErⅢ were obtained under the excitation of visible light by selective excitation of the IrⅢ-based *** was proven that Ir(dfppy)2(bpm)Cl as the ligand could effectively sensitize NIR emission from NdⅢ,YbⅢ,and ErⅢ.

关键词： bipyrimidine IrⅢ-LnⅢ bimetallic complexes stability constant NIR emission excitation of visible light

Permeability and selectivity synergistically enhanced nanofluidic membrane for osmotic energy harvesting

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Carbon Energy 2024年第8期6卷 14-24页

作者： Jundong Zhong Tingting Xu Hongyan Qi Weibo Sun Shuang Zhao Zhe Zhao Yirong Sun Youliang Zhu Jianxin Mu Haibo Zhang Xuanbo Zhu Zhenhua jiang lei jiang National and Local Joint Engineering Laboratory for Synthetic Technology of High‐Performance Polymer Jilin UniversityChangchunJilinChina State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchunJilinChina Key Laboratory for molecular Enzymology and Engineering of Ministry of Education Jilin UniversityChangchunJilinChina CAS Key Laboratory of Bio‐inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina

For the porous‐membrane‐based osmotic energy generator,the potential synergistic enhancement mechanism of various key parameters is still controversial,especially because optimizing the trade‐off between permeability and selectivity is still a ***,to construct a permeability and selectivity synergistically enhanced osmotic energy generator,the twodimensional porous membranes with tunable charge density are prepared by inserting sulfonated polyether sulfone into graphene *** of charge density and pore size on the ion transport are explored,and the ionic behaviors in the channel are calculated by numerical *** mechanism of ion transport in the process is studied in depth,and the fundamental principles of energy conversion are *** results demonstrate that charge density and pore size should be matched to construct the optimal ion *** collaborative enhancement strategy of permeability and selectivity has significantly improved the output power in osmotic energy generation;compared to the pure graphene oxide membrane,the composite membrane presents almost 20 times improvement.

关键词： blue energy generator charge tunable graphene oxide ion transport layered nanocomposites

Unidirectional movement behavior of underwater bubbles on the wettability gradient mesh via asymmetrical bounce

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Science china chemistry 2024年第8期67卷 2606-2613页

作者： Yuzhen Ning Zhihong Zhao Shuang Ben Qiang Li Cunming Yu Xudong Zhang Huawei Chen Kesong Liu lei jiang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology School of ChemistryBeihang UniversityBeijing 100191China Research institute of Aero-Engine Beihang UniversityBeijing 100191China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Tianmushan Laboratory Hangzhou 310023China The Analysis Testing CenterBeihang UniversityBeijing 100191China

The impact of underwater bubbles on solid surfaces with a gradient wettability is important for fundamental science and technological applications. Despite progress in the translational motion of underwater bubbles on asymmetric surface, a fundamental dynamic understanding of asymmetrical bounce behavior of the underwater bubble needs to be further ***, we investigate asymmetrical bounce of underwater bubbles after impacting the wettability gradient copper mesh *** bounce of the underwater bubble on the wettability gradient mesh(WGM) surface is composed by asymmetrical spread in the spread process and asymmetrical recoil in the recoil process, which induce the unidirectional movement ***, effective bubble-size manipulation can be easily implemented due to different volumes of bubbles remaining at different locations of WGM surface. We envision that this work will provide a new understanding of asymmetrical bounce behavior of the underwater bubble on the wettability gradient surface, and propose a novel and feasible strategy for constructing the underwater bubble manipulation system.

关键词： asymmetrical bounce unidirectional movement behavior gradient wettability

Co/N co-doped flower-like carbon-based phase change materials toward solar energy harvesting

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Aggregate 2024年第1期5卷 321-330页

作者： Xiao Chen lei Wang Yan Gao Yang Li Xiaowei Zhang Yu jiang Ge Wang institute of Advanced Materials Beijing Normal UniversityBeijingChina beijing Advanced Innovation center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule and Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingChina

The photothermal conversion capacity of pristine organic phase change materials(PCMs)is inherently insufficient in solar energy *** upgrade their photothermal conversion capacity,we developed bimetallic zeolitic imidazolate framework(ZIF)derived Co/N co-doped flower-like carbon(Co/N-FLC)-based composite PCMs toward solar energy harvesting.3D interconnected carbon framework with low interfacial thermal resistance,abundant carbon defects and high content of nitrogen doping,excellent localized surface plasmon resonance(LSPR)effect of Co nanoparticles,and light absorber Co_(3)ZnC in Co/N-FLC synergistically upgrade the photothermal capacity of(polyethylene glycol)PEG@Co/N-FLC composite PCMs with an ultrahigh photothermal conversion efficiency of 94.8%under 0.16 W/cm^(2).Uniformly anchored Co and Co_(3)ZnC nanoparticles in carbon framework guarantee excellent photon capture *** carbon nanotubes(CNTs)in 2D carbon nanosheets further accelerate the rapid transport of phonons by constructing cross-connected heat transfer ***,PEG@Co/N-FLC exhibits a thermal energy storage density of 100.69 J/g and excellent thermal stability and durable ***,PEG@Co/N-FLC composite PCMs are promising candidates to accelerate the efficient utilization of solar energy.

关键词： bimetallic ZIF Co/N co-doped carbon phase change materials photothermal conversion thermal energy storage

Fast prototype and rapid construction of three-dimensional and multi-scaled pitcher for controlled drainage by systematic biomimicry

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International Journal of Extreme Manufacturing 2024年第3期6卷 489-503页

作者： Tao Shen Ning Li Shijie Liu Cunlong Yu Chengqi Zhang Kang Yang Xingfei Li Ruochen Fang lei jiang Zhichao Dong Research institute for Frontier Science Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education BeijingSchool of ChemistryBeihang UniversityBeijing 100191People’s Republic of China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China CAS center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083People’s Republic of China School of Future Technology&School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 101407People’s Republic of China School of chemistry and Materials Science University of Science and Technology of China230026 HefeiAnhuiPeople’s Republic of China Suzhou institute for Advanced Research University of Science and Technology of China215123 SuzhouJiangsuPeople’s Republic of China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University300072 TianjinPeople’s Republic of China

Biomimetic materials that use natural wisdom to solve practical problems are developing *** trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial ***,rapid reconstruction of digital twin models with the same complex features as the prototype is ***,it faces bottlenecks and limits in fast characterization and fabrication,precise parameter optimization,geometricdeviations control,and quality *** solve these challenges,here,we demonstrate astate-of-the-art method taking advantage of micro-computed tomography and three-dimensional printing for the fast characterization of the pitcher plant Nepenthes x ventrata and fabrication of its biomimetic model to obtain a superior drainage controller with multiscale structures withprecise surface morphology optimization and geometric deviation ***-rupture-based drainage dynamic and mechanisms are characterized by x-ray and high-speed videography,which determines the crucial structures for unique *** the optimized artificial pitchers are further developed into sustained drainage devices with novel applications,such as detection,reaction,and smoke control.

关键词： systematic biomimicry biomimetic materials Micro-CT drainage digital twin

Allelic reprogramming of chromatin states in human early embryos

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National Science Review 2024年第3期11卷 58-71页

作者： Shenli Yuan lei Gao Wenrong Tao Jianhong Zhan Gang Lu Jingye Zhang Chuanxin Zhang Lizhi Yi Zhenbo Liu Zhenzhen Hou Min Dai Han Zhao Zi-jiang Chen jiang Liu Keliang Wu center for Reproductive Medicine Shandong University CAS Key Laboratory of Genome sciences and Information Collaborative Innovation Center of Genetics and Development Beijing Institute of Genomicsand China National Center for BioinformationChinese Academy of Sciences University of chinese academy of sciences CUHK-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciences the Chinese University of Hong Kong Key Laboratory of Reproductive Endocrinology of the Ministry of Education Shandong University center for Reproductive Medicine Ren Ji Hospital School of Medicine Shanghai Jiao Tong University CAS center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here,we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse *** allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early ***, allele-specific epigenomic reprogramming is different in humans and mice.

关键词： human embryo epigenetics reprogramming DNA methylation H3K27me3 chromatin accessibility

Hydrothermal synthesis of polyimide-linked covalent organic frameworks towards ultrafast and stable cathodic sodium storage

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Science china chemistry 2024年第4期67卷 1300-1310页

作者： Xiya Yang lei Gong Zhixin Liu Qianjun Zhi Baoqiu Yu Xin Chen Kang Wang Xiaofeng Li Dongdong Qi Jianzhuang jiang beijing Advanced Innovation center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Redox-active organic materials are capturing growing attention as cathode materials for sustainable alkaline metal ion ***,the storage of Na+in most organic materials-based cathodes is plagued by low capacity and unsatisfying rate performance due to their low active site densities and limited exposed active ***,two polyimide-linked covalent organic frameworks(COFs),namely HATN-PD-COF and HATN-TAB-COF,were fabricated from hydrothermal synthesis with redoxactive triphenylene-2,3,6,7,10,11-hexacarboxylic acid and aromatic amines as starting *** X-ray diffraction and electron microscopy analysis indicate the high crystalline nature of these COFs with AA stacking configuration and orderly mesoporous tunnel.N_(2) sorption measurement discloses the permanent porosity of these two COFs with a Brunauer-EmmettTeller surface area of 1,065-1,200 m^(2)g^(-1)and a large pore size of 2.0-3.1 *** intermittent titration technique and density functional theory calculations reveal the facile Na+ion diffusion along the mesoporous tunnel of these COFs with a small energy barrier of 0.13-0.40 e *** particular,the as-prepared COFs based-cathodes show ultrafast and stable Na+storage associated with their conjugated electronic structure,highly ordered mesoporous tunnel,robust structure,and redox-active C=N/C=O-rich framework as exemplified by the high reversible capacity of 210 m A h g^(-1)at 200 m A g^(-1),record-high rate performance(195 m A h g^(-1)at a high current density of 10,000 m A g^(-1))among organic electrodes and the capacity retention of nearly 91%at 10,000 m A g^(-1)after 7,000 cycles for HATN-PD-COF.

关键词： covalent organic framework sodium ion battery cathode high rate organic electrode