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Ultrasonic Vibration Electrical Discharge Machining in Gas

厦门大学学报（自然科学版） 2002年第S1期41卷 10-11页

作者： ZHANG qin-he, ZHANG jian-hua, DENG jian-xin, qin yong, NIU Zong-wei (College of Mechanical Engineering, Shandong University, Jinan 250061, China)

A new method of ultrasonic vibration electrical discharge machining(UEDM) in gas is proposed in this paper. In UEDM in gas, the gap between tool electrode and workpiece is small(about 0.01mm), and the voltage between them is higher than EDM in liquid, so short circuit is easy to take place. It is very important for improving the MRR to avoid short circuit. Therefore, some measures have been taken, a rotation and a planetary motion are superimposed upon the tool electrode. During UEDM in gas, workpiece is vibrating with ultrasonic frequency, which can have the molten workpiece material ejected out from base body of workpiece without being reattached to it again, it is very useful to increase MRR. The electrode is formed to be thin-walled pipe, the high pressure gas is supplied through the internal hole and flow over the machining gap with a high velocity. It can enhance the removal of molten and evaporated workpiece material. The gas with a high velocity also cools and solidifies the removed material and prevents them from adhering onto the surface of the tool electrode. Furthermore, during the pulse interval, the gas with a high velocity blows off the plasma formed by the previous discharge and decreases the temperatures of the discharge spots on the tool electrode and the workpiece due to heat transfer, thus guaranteeing the recovery of the dielectric strength of the gap. The experiments were performed on an electrical discharge small hole machine DK730(made in China, modified by author). The worktable of the machine was especially designed to accept an ultrasonic vibration unit, and the clamp of the machine was designed to accept high pressure gas when it turning. 45# steel and copper were selected as workpiece and tool electrode respectively. Air and oxygen gas were selected as gas mediums. Five sets of experiments were carried out to show the effects of open voltage, pulse duration, wall thickness of pipe electrode, amplitude of ultrasonic vibration and gas medi

关键词： UEDM gas medium MRR tool electrode wear

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Advancing gravitational theory through the tetrahedral constellation gravitational wave observatory

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 197-198页

作者： Yun-yong Wang Zhou-jian Cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing102206China

The Tetrahedral Constellation Gravitational Wave Observatory(TEGO)[1]represents a significant leap forward in gravitational wave detection,advancing our understanding of gravitational *** introducing a fourth spacecraft to form a tetrahedral configuration,TEGO enhances traditional triangular setups,enabling the simultaneous sensitivity to all six gravitational wave polarization modes,including those not predicted by general relativity.

关键词： wave polarization theory

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DKP-SLAM:A Visual SLAM for Dynamic Indoor Scenes Based on Object Detection and Region Probability

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Computers, Materials & Continua 2025年第1期82卷 1329-1347页

作者： Menglin Yin yong qin jiansheng Peng College of Automation Guangxi University of Science and TechnologyLiuzhou545000China Department of Artificial Intelligence and Manufacturing Hechi UniversityHechi546300China Key Laboratory of AI and Information Processing Education Department of Guangxi Zhuang Autonomous RegionHechi546300China Guangxi Key Laboratory of Sericulture Ecology and Applied Intelligent Technology School of Chemistry and BioengineeringHechi UniversityHechi546300China

In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and *** paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic ***,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed ***,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points *** process divides the image into low dynamic,suspicious dynamic,and high dynamic *** the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these *** with geometric methods,it detects and removes the dynamic *** final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments.

关键词： Visual SLAM dynamic scene YOLOX K-means++clustering dynamic probability

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Tunable Thermo-Responsive Shape Memory Materials Enabled by Poly(ε-caprolactone)-Poly(2-vinyl)ethylene Glycol Copolymers via Facile Thiol-Ene Photo-Crosslink

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Chinese Journal of Polymer Science 2025年第2期43卷 278-288页

作者： Ming-Hang Wang Fan Yang yong-jian Zhang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative Moleculesand School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240China Sichuan Research Institute Shanghai Jiao Tong UniversityChengdu610042China

Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical *** this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron *** thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory *** thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of ***,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL *** addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.

关键词： Shape memory polymers Polycaprolactone Thiol-ene photo-crosslink Controlled crosslinking density Tunable response temperature

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Evaluation of detonation performance of explosives ICM-101,ONC,and TNAZ based on improved VHL equation of state

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Defence Technology(防务技术) 2025年第2期44卷 83-97页

作者： yong Han qin Liu Yingliang Duan Yaqi Zhao Xinping Long Institute of Chemical Materials China Academy of Engineering PhysicsYouxian DistrictMianyang621000China China Academy of Engineering Physics Youxian DistrictMianyang621000China

Detonation performance is crucial for evaluating the power of high explosives(HEs),and the equation of state(EOS)that accurately describes the high-temperature,high-pressure,and high-temperature,medium-pressure states of detonation products is key to assessing the damage efficiency of these energetic *** article examines the limitations of the VLW EOS in representing the thermodynamic states of explosive detonation gas products under high-temperature and medium-to high-pressure conditions.A new gas EOS for detonation products,called VHL(Virial-Han-Long),is *** accuracy of VHL in describing gas states under high-temperature and medium-to high-pressure conditions is verified,and its performance in evaluating explosive detonation and working capabilities is *** results demonstrate that VHL exhibits high precision in calculating detonation ***,the detonation performance of three new HEs(ICM-101,ONC,and TNAZ)was calculated and compared to traditional HEs(TATB,CL-20,and HMX).The results indicate that ONC has superior detonation performance compared to the other explosives,while ICM-101 shows a detonation velocity similar to CL-20 but with slightly lower detonation *** detonation characteristics of TNAZ are comparable to those of the standard HE *** the perspective of products,considering the comprehensive work performance(mechanical work and detonation heat),both ONC and ICM-101demonstrate relatively superior performance.

关键词： Equation of state Detonation performance Working capability Thermodynamics High explosive

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Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： Tian qin Yuxin Jin Yiming qin Feifei Yuan Hongbin Lu jianzhong Hu yong Cao Chengjun Li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2

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Effect of lanthanum on microstructure of a nickel-based single crystal superalloy

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China Foundry 2025年第1期22卷 55-64页

作者： Hong Gao Kai Guan Ren-jie Cui jian-chao qin Zi-han Zhao Zhao-hui Huang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China

To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.

关键词： single crystal superalloy lanthanum microstructure heat-treatment precipitate phase

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Porous framework materials for CO2 capture

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Journal of Energy Chemistry 2025年第2期101卷 278-297页

作者： Ziying Zhang Yu Dai Shiyi Zhang Liyi Chen jian Gu yong Wang Weiwei Sun School of Environmental and Chemical Engineering Shanghai University

Due to the significant impact of carbon dioxide on global ecology,more efforts have been put into the exploration on CO2capture and *** organic framework materials,as a kind of materials with high porosity and designable structure,have been considered as effective host materials for adsorbing carbon dioxide or separating it from other *** review gives a deep insight into the applications of metal-organic frameworks,covalent-organic frameworks,and other porous frameworks on CO2capture,focusing on the enhanced capture performances originated from their high surface area with abundant porous structure,functional groups with specific heteroatoms modification,or other building unit ***,the main challenges associated with porous frameworks for CO2capture and proposed strategies to address these obstacles,including the structural design strategy or the capture mechanism exploration,have been demonstrated and *** review can contribute to further investigation on porous frameworks for gas capture and separation with enhanced performance and efficiency.

关键词： Adsorption mechanism CO2 capture Modification Organic frameworks

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Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie Zhang jian Yang Jia Ran Jiqiang Ning Haiyan Wang yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal UniversityJinhua 321004ZhejiangChina Jinhua Advanced Research Institute Jinhua 321019ZhejiangChina Department of Optical Science and Engineering Fudan UniversityShanghai 200438China College of Chemistry and Materials Engineering Zhejiang A&F UniversityHangzhou 311300ZhejiangChina

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF)has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA),but there still remain problems such as limited yield,short cycle life,and ambiguous reaction *** many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF,a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still *** herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA,particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts,including heterointerface construction,defect engineering,single-atom engineering,and in situ *** characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated,and challenges and future directions of electrochemical oxidation of HMF are also *** review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Electrochemical oxidation of 5- hydroxymethylfurfural 2,5-Furan dicarboxylic acid Structural design Mechanism Electrocatalysts

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Potential preservative mechanisms of cardiac rehabilitation pathways on endothelial function in coronary heart disease

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Science China(Life Sciences) 2025年第1期68卷 158-175页

作者： Wen-Tao Sun jian-yong Du Jia Wang Yi-Long Wang Er-Dan Dong Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital(Qingdao Municipal Hospital)Schoolof Health and Life SciencesUniversityof Health and Rehabilitation SciencesQingdao 266071China Department of Cardiology and Instituteof Vascular Medicine Peking University Third HospitalTheInstituteofCardiovascular SciencesPeking UniversityState Key Laboratoryof Vascular Homeostasisand RemodelingPeking UniversityBeijing 100191China

Cardiac rehabilitation,a comprehensive exercise-based lifestyle and medical management,is effective in decreasing morbidity and improving life quality in patients with coronary heart *** function,an irreplaceable indicator in coronary heart disease progression,is measured by various methods in traditional cardiac rehabilitation pathways,including medicinal treatment,aerobic training,and smoking ***,studies on the effect of some emerging cardiac rehabilitation programs on endothelial function are *** article briefly reviewed the endothelium-beneficial effects of different cardiac rehabilitation pathways,including exercise training,lifestyle modification and psychological intervention in patients with coronary heart disease,and related experimental models,and summarized both uncovered and potential cellular and molecular mechanisms of the beneficial roles of various cardiac rehabilitation pathways on endothelial *** exercise training and some lifestyle interventions,the enhanced bioavailability of nitric oxide,increased circulating endothelial progenitor cells(EPCs),and decreased oxidative stress are major contributors to preventing endothelial dysfunction in coronary heart ***,the preservation of endothelial-dependent hyperpolarizing factors and inflammatory suppression play *** the one hand,to develop more endothelium-protective rehabilitation methods in coronary heart disease,adequately designed and sized randomized multicenter clinical trials should be advanced using standardized cardiac rehabilitation programs and existing assessment *** the other hand,additional studies using suitable experimental models are warranted to elucidate the relationship between some new interventions and endothelial protection in both macro-and microvasculature.

关键词： cardiac rehabilitation coronary heart disease endothelial function

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