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Bio-inspired Design and Inverse Kinematics Solution of an Omnidirectional Humanoid Robotic Arm with Geometric and Load Capacity Constraints

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Journal of Bionic Engineering 2024年第2期21卷 778-802页

作者： zhichao zhu Zirong Luo Yiming zhu Tao Jiang Minghai Xia Shanjun Chen Boyu Jin College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

Inspired by the driving muscles of the human arm,a 4-Degree of Freedom(DOF)concentrated driving humanoid robotic arm is proposed based on a spatial double parallel four-bar mechanism.The four-bar mechanism design reduces the inertia of the elbow-driving unit and the torque by 76.65%and 57.81%,respectively.Mimicking the human pose regulation strategy that the human arm picks up a heavy object by adjusting its posture naturally without complicated control,the robotic arm features an integrated position-level closed-form inverse solution method considering both geometric and load capacity limitations.This method consists of a geometric constraint model incorporating the arm angle(φ)and the Global Configuration(GC)to avoid joint limits and singularities,and a load capacity model to constrain the feasible domain of the arm angle.Further,trajectory tracking simulations and experiments are conducted to validate the feasibility of the proposed inverse solution method.The simulated maximum output torque,maximum output power and total energy consumption of the robotic arm are reduced by up to 2.0%,13.3%,and 33.3%,respectively.The experimental results demonstrate that the robotic arm can bear heavy loads in a human-like posture,effectively reducing the maximum output torque and energy consumption of the robotic arm by 1.83%and 5.03%,respectively,while avoiding joints beyond geometric and load capacity limitations.The proposed design provides a high payload–weight ratio and an efficient pose control solution for robotic arms,which can potentially broaden the application spectrum of humanoid robots.

关键词： Humanoid robotic arm Bio-inspired design Inverse kinematics solution Load capacity constraint Geometric constraint

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Edge and lithium concentration effects on intercalation kinetics for graphite anodes

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Journal of Energy Chemistry 2024年第3期90卷 337-347,I0009页

作者： Keming zhu Denis Kramer chao Peng School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048ShanxiChina Faculty of Mechanical Engineering Helmut-Schmidt UniversityHamburg 22043Germany School of Engineering University of SouthamptonSouthampton SO171BJUK Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina

Graphite interfaces are an important part of the anode in lithium-ion batteries(LIBs),significantly influencing Li intercalation kinetics.Graphite anodes adopt different stacking sequences depending on the concentration of the intercalated Li ions.In this work,we performed first-principles calculations to comprehensively address the energetics and dynamics of Li intercalation and Li vacancy diffusion near the no n-basal edges of graphite,namely the armchair and zigzag-edges,at high Li concentration.We find that surface effects persist in stage-Ⅱ that bind Li strongly at the edge sites.However,the pronounced effect previously identified at the zigzag edge of pristine graphite is reduced in LiC_(12),penetrating only to the subsurface site,and eventually disappearing in LiC_(6).Consequently,the distinctive surface state at the zigzag edge significantly impacts and restrains the charging rate at the initial lithiation of graphite anodes,whilst diminishes with an increasing degree of lithiation.Longer diffusion time for Li hopping to the bulk site from either the zigzag edge or the armchair edge in LiC_(6) was observed during high state of charge due to charge repulsion.Effectively controlling Li occupation and diffusion kinetics at this stage is also crucial for enhancing the charge rate.

关键词： Graphite anode Edge Interface Lithium-ion batteries Density functional theory

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Clinical analysis of multiple primary gastrointestinal malignant tumors:A 10-year case review of a single-center

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1204-1212页

作者： Cheng-Lou zhu Ling-zhi Peng The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Surgical Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Multiple primary malignant tumors(MPMTs)was first described by Billroth as early as 1889,with the first report published by Warren and Gates in 1932.Since then,numerous cases have been reported.A literature review of 1104269 patients with cancer revealed that the incidence of MPMTs ranged from 0.73 to 11.7%.In recent years,however,there has been a significant upward trend in the incidence of this phenomenon,which may be associated with many different factors,including the advancement of modern diagnostic procedures facilitating the examination and diagnosis of more MPMTs,increased exposure to chemotherapy and radiotherapy that exacerbate the risk of new malignant tumors in patients with cancer,and prolonged survival of patients with cancer allowing sufficient time for the development of new primary cancers.AIM To analyze the incidence,clinical features,treatment factors,prevalence,and prognosis of patients with MPMTs in the gastrointestinal tract treated in a single center.Additionally,we analyzed the different tumor combinations,time interval between the occurrence of tumors,and staging.METHODS This retrospective cohort study analyzed 8059 patients with pathologically confirmed gastrointestinal malignant tumors treated at the Gansu Province Hospital in Lanzhou,Gansu,China between June 2011 and June 2020.Of these,85 patients had MPMTs.The clinical features,treatment factors,prevalence,and prognosis of this latter cohort were analyzed.RESULTS The incidence of MPMTs in patients with gastrointestinal malignant tumors was 1.05%(85/8059),including 83 double primary malignant tumors and two triple primary malignant tumors of which 57(67.06%)were synchronous MPMTs(SMPMTs)and 28(32.94%)were metachronous MPMTs(MMPMTs).The most frequent associations were found between the rectum colon cancers within the SMPMT category and the gastric-colon cancers within the MMPMT category.For the MMPMTs,the median interval was 53 months.The overall 1-,3-and 5-year survival rates from diagnosis of the first primary cancer were 9

关键词： Multiple primary malignant tumors Clinical characteristics Gastrointestinal tract Prognosis Epidemiology

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Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

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Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： zhi-Kang Chen Wu-chao Zhao Yi-Ling Zhao Cong-Lei Liu Liu-Yin Jiang Yue-Tao Zhang Hong-Ping zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

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Investigation on bonding interfaces of an SA508 steel billet manufactured by additive forging

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Journal of Iron and Steel Research(International) 2022年第12期29卷 2016-2023页

作者： Xin-jin Zhang Tian-sheng Wang zhi-chao zhu Lin zhu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina China First Heavy Industries Co. Ltd.Qiqihaer 161042HeilongjiangChina

An experimental steel billet of SA508 reactor pressure vessel material was manufactured by the additive forging method,and microstructure and mechanical properties of the hot-compression bonding interface were systematically investigated.The result indicated that oxidation levels of bonding interfaces were well controlled using vacuum electron beam welding.It was easy to discriminate interfaces from base materials during the optical microstructure observation,since interfaces were characterized by grain or phase boundaries in a straight line.Test results of uniaxial tensile experiments(at 20 and 350°C)and Charpy V-notched impact tests(at 0 and 20°C)showed that fracture behaviour of all those samples appeared at the base material,and bonding interfaces showed advantage of strength and toughness at the forge bonding state.

关键词： Reactor pressure vessel Additive forging Interfacial microstructure Mechanical property

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Reinforcing oxygen electrocatalytic activity via selective dualphase heterointerface engineering for rechargeable Zn-air batteries

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Rare Metals 2024年第4期43卷 1524-1536页

作者： chao Cheng Chuang zhi Zhong-Ti Sun Yong-Qiang Ming Ting-Ting Xiang Qing-chao zhu Zi-Rui Wu Bing Li Yi Li Cheng Jin Yong Cao Juan Yang School of Materials Science and Engineering Jiangsu University Faculty of Material Science and Engineering Kunming University of Science and Technology

Dual-phase heterointerface electrocatalysts（DPHE） constructed by oxygen reduction reaction（ORR）-and oxygen evolution reaction（OER）-active elements exhibit excellent bifunctional activity and long-term durability due to the abundant interface exposure and synergistic catalytic effect.Herein,low-dimensional N-doped graphene nanoribbons（N-GNRs） coupling with ultrathin CoO nanocomposites（N-GNRs/CoO） were controllably fabricated through a facile two-step approach using synthesized Co（OH）2nanosheet as CoO precursor.Density functional theory（DFT） calculations and experimental characterizations prove that the formation of interface between N-GNRs and CoO can induce local charge redistribution,contributing to the improvement of catalytic activity and stability.The optimal N-GNRs/CoO DPHE possesses hierarchically porous architectures and presents outstanding bifunctional activities with a small potential gap of 0.729 V between the potential at 10 mA·cm-2for OER and the halfwave potential for ORR,which outperforms Pt/C+IrO2and the majority of noble-metal-free bifunctional catalysts.Liquid-and solid-state rechargeable Zn-air batteries assembled with N-GNRs/CoO as the cathode also display high peak power density and fantastic cycle stability,superior to that of benchmark Pt/C +IrO2catalyst.It is anticipated to offer significant benefits toward high activity,stability and mechanical flexibility bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries.

关键词： Interface engineering Graphene nanoribbons CoO Bifunctional electrocatalyst Zn–air batteries

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Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-zhi Lin Lu-Kun Feng Ya-Dong Li chao-Fan Chang Cai-Zhen zhu Ming-Liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of polymers.Our approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric constant.We validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric constants.Furthermore,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and polarizability.The resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in experiments.Our findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

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Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang Zu-chao zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental validation.The experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly analyzed.The cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation formed.The formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of cavitation.In addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid change.This phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

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Endovascular treatment of ruptured lobulated anterior communicating artery aneurysms:A retrospective study of 24 patients

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World Journal of Clinical Cases 2024年第15期12卷 2529-2541页

作者： Sheng-Xuan Huang Xun-Ping Ai Ze-Hui Kang zhi-Yong Chen Ren-Man Li Zu-chao Wu Feng zhu Department of Neurosurgery Sanming First Hospital Affiliated to Fujian Medical UniversitySanming 365000Fujian ProvinceChina

BACKGROUND Lobulated intracranial aneurysm is a special type of aneurysm with at least one additional cyst in the neck or body of the aneurysm.Lobulated intracranial aneurysm is a complex aneurysm with complex morphology and structure and weak tumor wall,which is an independent risk factor for rupture and hemorrhage.Lobular aneurysms located in the anterior communicating artery complex account for 36.9%of all intracranial lobular aneurysms.Due to its special anatomical structure,both craniotomy and endovascular treatment are more difficult.Compared with single-capsule aneurysms,craniotomy for lobular intracranial aneurysms has a higher risk and complication rate.AIM To investigate the efficacy and safety of endovascular treatment for ruptured lobulated anterior communicating artery aneurysm(ACoAA).METHODS Patients with ruptured lobulated ACoAA received endovascular treatment in Sanming First Hospital Affiliated to Fujian Medical University from June 2020 to June 2022 were retrospectively included.Their demographic,clinical and imaging characteristics,endovascular treatment methods and follow-up results were collected.RESULTS A total of 24 patients with ruptured lobulated ACoAA were included,including 9 males(37.5%)and 15 females(62.5%).Their age was 56.2±8.9 years old(range 39-74).The time from rupture to endovascular treatment was 10.9±12.5 h.The maximum diameter of the aneurysms was 5.1±1.0 mm and neck width were 3.0±0.7 mm.Nineteen patients(79.2%)were double-lobed and 5(20.8%)were multilobed.Fisher's grade:Grade 2 in 16 cases(66.7%),grade 3 in 6 cases(25%),and grade 4 in 2 cases(8.3%).Hunt-Hess grade:Grade 0-2 in 5 cases(20.8%),grade 3-5 in 19 cases(79.2%).Glasgow Coma Scale score:9-12 in 14 cases(58.3%),13-15 in 10 cases(41.7%).Immediately postprocedural Raymond-Roy grade:grade 1 in 23 cases(95.8%),grade 2 in 1 case(4.2%).Raymond-Roy grade in imaging follow-up for 2 wk to 3 months:grade 1 in 23 cases(95.8%),grade 2 in 1 case(4.2%).Followup for 2 to 12 months showed that 21 patients(87.5%)had good functional o

关键词： Intracranial aneurysm Anterior cerebral artery Endovascular surgery Embolism Treatment outcome

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High-resolution tsunami hazard assessment for the Guangdong-Hong Kong-Macao Greater Bay Area based on a non-hydrostatic tsunami model

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Science China Earth Sciences 2024年第7期67卷 2326-2351页

作者： Yifan zhu chao AN Houyun YU Wei ZHANG Xiaofei CHEN Key Laboratory of Hydrodynamics(Ministry of Education) School of Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Earth and Space Sciences Southern University of Science and Technology Shenzhen 518055China

The Guangdong-Hong Kong-Macao Greater Bay Area(GBA)is threatened by potential tsunami hazards from the Littoral Fault Zone(LFZ)and the Manila subduction zone(MSZ),and may suffer huge damage because of its dense population,concentrated infrastructure,and low-lying coasts.Previous tsunami studies for the GBA made simple assumptions on the mechanisms of LFZ earthquakes,and used coarse bathymetry data in tsunami simulation,which limited the prediction of detailed tsunami hazard characteristics.In this paper,we develop a parallel dispersive tsunami model PCOMCOT to efficiently simulate dispersive,nonlinear,and breaking tsunami waves.We also construct large-scale and high-resolution bathymetry models for the GBA by correcting and integrating various data sources.Dynamic rupture simulation is performed for the LFZ to obtain a more reliable earthquake source model.We propose several representative earthquake scenarios for the LFZ and MSZ,and use PCOMCOT to calculate the resulting tsunami waves,currents,and inundation in the GBA.Our results indicate that if an M_(w)7.5 oblique-slip earthquake occurs in the LFZ off the Pearl River Estuary(PRE),the subsequent tsunami will primarily impact Hong Kong,causing maximum positive and negative waves of around 1 m and -2 m,respectively,along with slightly destructive currents(≥1.5 m/s).An M_(w)9.0 MSZ megathrust earthquake can lead to widespread inundation with>1 m depth on the outlying islands of Macao and in the urban areas of Hong Kong around the Victoria Harbour.Besides,it will also cause catastrophic tsunami currents along the narrow waterways in Hong Kong and Macao,and the spatial distribution of strong currents(≥3 m/s)shows a considerable discrepancy from the areas of serious inundation.Thus,more attention should be paid to the potential impacts of tsunami currents on the GBA.

关键词： Tsunami hazards Inundation Tsunami currents Non-hydrostatic model Guangdong-Hong Kong-Macao Greater Bay Area

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