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Impact of Bubbles on Mechanical Performances in a Borosilicate Glass

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 25-29页

作者： li Chengxing li Dongfeng MA Shilong QIAO Ang zheng Qingshuang China Helicopter Research and Development Institute Jingdezhen 333001China State Key Laboratory of Silicate Materials for Ar-chitectures Wuhan University of TechnologyWuhan 430070China

To analyze the impact of bubbles on the mechanical behavior of glasses,by controlling the refining time,we prepared three borosilicate glasses with the same composition and different *** the analysis software integrated within the optical microscope,the diameter and number of the bubbles on the surface of three borosilicate glasses were *** the hardness and crack initiation resistance(CR),we built the relationship between the porosity and the mechanical performance of these borosilicate glasses.

关键词： bubbles oxide glass hardness creak initiation resistance

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全自动装盒机软袋下袋机构总成的设计

食品与机械 2008年第3期24卷 84-86页

作者：刘恒珍李正瑞上海龙腾机械制造有限公司上海201314

为克服现有软袋包装设备中软袋下袋机构所存在的缺陷,提高软袋包装产品装盒的效率,在软袋输送带总成下袋口位置上方设置计数器,通过控制装置和驱动机构驱动每层可调节料仓沿着导轨滑块的方向开合,完成数袋下袋动作,从而达到软袋下袋经... 详细信息

为克服现有软袋包装设备中软袋下袋机构所存在的缺陷,提高软袋包装产品装盒的效率,在软袋输送带总成下袋口位置上方设置计数器,通过控制装置和驱动机构驱动每层可调节料仓沿着导轨滑块的方向开合,完成数袋下袋动作,从而达到软袋下袋经济简单、动作平稳可靠、高速自动、下袋数量准确并可任意调整,使之更具有经济性和适用性。

关键词：装盒机软袋下袋机构驱动机构料仓

Integrating XML with CORBA-Based Multidatabase Systems

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 676-680页

作者： lirui-xuan LUzheng-ding WUWei XIAOWei-jun CollegeofComputerScienceandTechnology HuazhongUniversityofScienceandTechnology.Wuhan430074Hubei.China

In this paper, we first introduce the architecture for a CORBA-based multidatabase system and then give an approach of schema mapping between XML and relational database system. Finally, we investigate the ability to apply the integration of XML with CORBA-based multidatabase systems. This integration extends the ability of a CORBA-based multidatabase system to implement data sharing and interoperability. Key words heterogeneity - XML - schema mapping - multidatabase systems CLC number TP311. 13 Foundation item: Supported by the National Key Technologies R&D Program of China(2002BA103A04)Biography: li rui-xuan(1974-), male, Ph. D candidate, research interests: heterogeneous information integration.

关键词： heterogeneity XML schema mapping multidatabase systems

Leader-follower: Human-centered intention-guided controller for novel Superlimb with application to load-carrying scenarios

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Science China Technological Sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong li Hongwei JING Kerui SUN Yuancheng li Sikai ZHAO Lele li Haotian JU Ziqi WANG rui WU Tianjiao zheng Jie ZHAO Yanhe ZHU The State Key Laboratory of Robotics and System Harbin Institute of Technology The Learning Algorithms and Systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

Supernumerary robotic arms(Superlimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–Superlimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of Superlimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the Superlimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between Superlimb, humans, and the environment under human safety assurance. First, the human–Superlimb dynamic system is modeled to achieve force interaction with the environment and wearer. Second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed Swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–Superlimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the Superlimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and Superlimb could well understand the wearer's intentions to switch different Superlimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong zheng Jialin Chen Jinghong Xu Bin Jiang Lei li Yawei li Yuliang Dai Bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

Small extracellular vesicles derived from cerebral endothelial cells with elevated microRNA 27a promote ischemic stroke recovery

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Neural Regeneration Research 2025年第1期20卷 224-233页

作者： Yi Zhang Zhongwu liu Michael Chopp Michael Millman Yanfeng li Pasquale Cepparulo Amy Kemper Chao li li Zhang zheng Gang Zhang Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA Department of Pathology Henry Ford HospitalDetroitMIUSA Division of Pharmacology Department of NeuroscienceReproductive and Dentistry SciencesSchool of MedicineUniversity of Naples“Federico Ⅱ”NaplesItaly

Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional *** previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endothelial cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic *** the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression *** EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a *** male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or *** array of behavior assays was used to measure neurological *** with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological *** vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal *** analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct *** of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of *** data provide evidence that 27a-sEVs have

关键词： axonal remodeling cerebral endothelial cells exosomes miR-27a mitochondria Semaphorin 6A small extracellular vesicles stroke

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全自动装盒机灯泡下泡机构的设计

包装工程 2008年第6期29卷 81-83页

作者：刘恒珍李正瑞上海龙腾机械制造有限公司上海201314

设计开发装盒机的灯泡下泡机构,使目前国内普通灯泡手工装盒改为全自动的机械装盒,克服灯泡排成一排,快速准确的落入装盒机船舱的问题。应用两导轨与压条形成的储存腔倾斜一定角度,把灯泡排成一排,便于自动下落,高速步进电机带动曲柄连... 详细信息

设计开发装盒机的灯泡下泡机构,使目前国内普通灯泡手工装盒改为全自动的机械装盒,克服灯泡排成一排,快速准确的落入装盒机船舱的问题。应用两导轨与压条形成的储存腔倾斜一定角度,把灯泡排成一排,便于自动下落,高速步进电机带动曲柄连杆驱动灯泡挡板摆动,通过装盒机的编码器使其摆动频率与装盒机的运动船舱同步,从而达到灯泡下泡经济简单、动作可靠、效率高、下泡准确并可任意调整的灯泡下泡机构,使之更具有经济性和适用性。

关键词：装盒机灯泡下泡机构曲柄连杆导轨

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong li Peng Ai Wanrong Guo Tuo zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie li Wenbo Yu Zhenyu Sun Weichen zheng liangwei Zhang Yanling Xue Wenning liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment