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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： Yan-jiang Li Meng-Long Hu Jun-Wen Zhang qiang fu Jie Zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-Hao Yang Tong Wu qiang fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Gelfand-Kirillov Dimension and Reducibility of Scalar Generalized Verma Modules for Classical Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 658-706页

作者： Zhan qiang BAI Jing jiang School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China E-mail:zqbai@*** jjsd6514@***

Let g be a classical complex simple Lie algebra and q be a parabolic *** M be a generalized Verma module induced from a one dimensional representation of *** M is called a scalar generalized Verma *** this paper,we will determine the reducibility of scalar generalized Verma modules associated to maximal parabolic subalgebras by computing explicitly the Gelfand-Kirillov dimension of the corresponding highest weight modules.

关键词： Generalized Verma module Gelfand-Kirillov dimension Young tableau

MADDPG-D2: An Intelligent Dynamic Task Allocation Algorithm Based on Multi-Agent Architecture Driven by Prior Knowledge

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2559-2586页

作者： Tengda Li Gang Wang qiang fu College of Air and Missile Defense Air Force Engineering UniversityXi’an710051China

Aiming at the problems of low solution accuracy and high decision pressure when facing large-scale dynamic task allocation(DTA)and high-dimensional decision space with single agent,this paper combines the deep reinforce-ment learning(DRL)theory and an improved Multi-Agent Deep Deterministic Policy Gradient(MADDPG-D2)algorithm with a dual experience replay pool and a dual noise based on multi-agent architecture is proposed to improve the efficiency of *** algorithm is based on the traditional Multi-Agent Deep Deterministic Policy Gradient(MADDPG)algorithm,and considers the introduction of a double noise mechanism to increase the action exploration space in the early stage of the algorithm,and the introduction of a double experience pool to improve the data utilization rate;at the same time,in order to accelerate the training speed and efficiency of the agents,and to solve the cold-start problem of the training,the a priori knowledge technology is applied to the training of the ***,the MADDPG-D2 algorithm is compared and analyzed based on the digital battlefield of ground and air *** experimental results show that the agents trained by the MADDPG-D2 algorithm have higher win rates and average rewards,can utilize the resources more reasonably,and better solve the problem of the traditional single agent algorithms facing the difficulty of solving the problem in the high-dimensional decision *** MADDPG-D2 algorithm based on multi-agent architecture proposed in this paper has certain superiority and rationality in DTA.

关键词： Deep reinforcement learning dynamic task allocation intelligent decision-making multi-agent system MADDPG-D2 algorithm

Ultrafast optical investigation of carrier and spin dynamics in low-dimensional perovskites

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Science China(Technological Sciences) 2024年第1期67卷 2-18页

作者： fu JinYue jiang Ying FANG HongHua Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410012China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Low-dimensional perovskite(PVK)materials have attracted significant research interest,because of their quantum-confined effect,tunable band gap structures,and higher stability than that of three-dimensional(3D)*** semiconductor optoelectronic devices,high speed and small size are closely *** development of high-speed devices requires researchers to fully understand the properties of materials,especially the dynamic processes such as carrier recombination,separation,and transport,which often play a crucial role in the performance of *** an indispensable part of dynamic research,spin relaxation is also of great significance in studying the properties of materials and explore possible *** halide PVK materials have strong spin-orbit coupling(SOC),which provides a basis for information storage and processing by using spin degrees of ***,studying the carrier and spin dynamics of low-dimensional PVKs is an effective way to understand the internal properties of low-dimensional PVKs *** paper summarizes the latest research progress on the ultrafast carrier and spin dynamics in low-dimensional PVKs,to comprehensively understand their carrier and spin behaviors and present an outlook for relevant studies in this area.

关键词： low-dimensional perovskites carrier dynamics spin dynamics optoelectronic devices

Impact of initial fluctuations and nuclear deformations in isobar collisions

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Nuclear Science and Techniques 2024年第6期35卷 155-162页

作者： Jian-Fei Wang Hao-Jie Xu fu-qiang Wang Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Science Huzhou UniversityHuzhou 313000China Strong-Coupling Physics International Research Laboratory(SPiRL) Huzhou UniversityHuzhou 313000China Department of Physics and Astronomy Purdue UniversityWest LafayetteIN 47907USA

Relativistic isobar^(96)_(44)Ru+^(96)_(44)Ru and^(96)_(40)Zr+^(96)_(40)Zrcollisions have revealed intricate differences in their nuclear size and shape,inspiring unconventional studies of nuclear structure using relativistic heavy ion *** this study,we investigate the relative differences in the mean multiplicityR_()and the secondR_(ε2)and third-order eccentricityR_(ε3)between isobar collisions using initial state Glauber *** is found that initial fluctuations and nuclear deformations have negligible effects on R_()in most central collisions,while both are important for the R_(ε2)and R_(ε3),the degree of which is sensitive to the underlying nucleonic or sub-nucleonic degree of *** features,compared to real data,may probe the particle production mechanism and the physics underlying nuclear structure.

关键词： Relativistic isobar collisions Initial fluctuations Nuclear deformation

The Effect of Key Nodes on theMalware Dynamics in the Industrial Control Network

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Computers, Materials & Continua 2024年第4期79卷 329-349页

作者： qiang fu JunWang Changfu Si Jiawei Liu College of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China College of Computer Science and Engineering Northeastern UniversityShenyang110169China

As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of *** connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security *** paper proposes a model for the industrial control *** includes a malware containment strategy that integrates intrusion detection,quarantine,and ***,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment *** addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction ***,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is *** otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control *** earlier the immunization of key nodes,the *** the time exceeds the threshold,immunizing key nodes is almost *** analysis provides a better way to contain the malware in the industrial control network.

关键词： Key nodes dynamic model industrial control network simulation

Circadian disturbance induces erectile dysfunction by impairing endothelial function

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Asian Journal of Andrology 2024年第2期26卷 205-211页

作者： Tao Li Yi-Ting jiang Xin-Zhu Qi Peng Chen Jun-Hao Zhang fu Luo Jun Qiao jiang Gu Guang-Shi Du qiang Wang Department of Urology Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Urology Guizhou Provincial People's HospitalGuiyang 550002China Department of Otorhinolaryngology Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004China Guizhou Institute for Food and Drug Control Guiyang 550004China Department of Reproductive Center Guizhou Provincial People's HospitalGuiyang 550002China Translational Medicine Research Center of Guizhou Medical University Guiyang 550025China

In order to explore the impact of circadian disturbance on erectile function,we randomly divided 24 adult male rats into groups of control(light on at 8:00 *** off at 8:00 p.m.),dark/dark(DD;constant dark),light/light(LL;constant light),and shift dark/light(DL;light off at 8:00 *** on at 8:0o p.m.).Four weeks later,erectile function was measured and corpora cavernosa were harvested for *** maximum intracavernous pressure(mlcP)and mCP/mean arterial pressure(MAP)ratio in the DD,LL,and DL groups were significantly lower than that in the control *** LL and DL groups showed significantly attenuated endothelial nitric oxide synthase(eNOS),while DD,LL,and DL showed reduced neuronal nitric oxide synthase(nNOS)at both mRNA and protein *** production of nitric oxide(NO)and cyclic guanosinemonophosphate(cGMP)was inhibited by altered light/dark cycles to varying *** disturbance impaired endothelial function and contributed to erectile *** the core circadian elements,mRNA expression of circadian locomotor output cycles kaput(Clock)and brain/muscle aryl-hydrocarbon receptor nuclear translocator-like protein 1(Bmal1)was elevated in the DL group,but their protein expression was not significantly ***,LL,and DL increased period 1(Per1)and Per3 levels,while LL and DL increased PER1 *** significant difference was found for Per2levels,and PER2 and PER3 concentrations were not significantly ***,LL and DL significantly increased cryptochrome-1(CRY1)and CRY2 at both mRNA and protein *** altered light/dark rat model showed that circadian disturbance contributed to erectile dysfunction probably by impairing endothelial ***,the core circadian elements were detected in the corpora cavernosa,but these were ***,which circadian element regulates erectile function and how it works need further analysis.

关键词： circadian disturbance endothelial function erectile function light/dark cycle NO/cGMP

Metal reflector-enhanced thermoacoustic imaging as a guidance for puncture biopsy

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Journal of Innovative Optical Health Sciences 2024年第6期17卷 83-96页

作者： Shuang Du Tao qiang Zihui Chi Huabei jiang School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065P.R.China Department of Medical Engineering University of South FloridaTampaFL 33620USA

Puncture biopsy is an important clinical technique to obtain diseased tissue for pathological diagnosis,where imaging guidance is *** this paper,we describe a metal reflector-enhanced microwave-induced thermoacoustic imaging(TAI)approach capable of guiding puncture biopsy for detection of breast cancer and joint *** experimentations simulating puncture guidance in breast cancer and knee gout models werefirst conducted using(CST STUDIO SUITE)(CST)software,and then ex-vivo experiments were performed followed by qualitative observations and semi-quantitative *** results of both the simulations and ex-vivo experiments showed that our reflector-enhanced TAI could image the puncture needle in high resolution with a large depth of>12 cm.

关键词： Microwave-induced thermoacoustic imaging puncture guidance reflector

Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin Xue Chao Zheng fu-qiang Lai Xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping