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Chinese Journal of Polymer Science 2024年第8期42卷 1185-1197页

作者： Zhi-Ying Zhao Hao Jiang Xiao-Dong li Xu-Dong Zhang xing Su Mei-Shuai zou School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The packaging materials with cushioning performance are used to prevent the internal contents from being damaged by the impact and vibration of external *** polyurethane microcellular elastomers(PUMEs)can absorb energy through cell collapse and molecular chain *** this study,PUMEs with different densities were investigated by scanning electron microscopy,dynamic mechanical analysis and dynamic compression *** exhibited significant im pact resistance and the maximum peak stress attenuation ratio reached 73.33%.The protective equipment was made by PUME with the optimal density of 600 kg/m^(3),and then the acceleration sensing device installed with the same protective equipment fell from a height of 3,5 and 10 m to evaluate the energy-absorbing property and reusability of *** results showed that PUMEs equipment reduced the peak acceleration of the device by 93.84%,with a maximum deviation of 9%between actual test and simulation,and shortened the impact time of first landing by 57.39%.In addition,the equipment PUMEs equipment could effectively reduce the stress on the protected items.

关键词： Polyurethane microcellular elastomer Impact velocity Stress attenuation ratio Impact resistance

Security-Reliability Tradeoff Analysis for Jamming Aided Decode-and-Forward Relay Networks

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China Communications 2024年第5期21卷 218-228页

作者： zou Ronggui zou Yulong Zhu Jia li Bin School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

In this paper,we explore a cooperative decode-and-forward(DF)relay network comprised of a source,a relay,and a destination in the presence of an *** improve physical-layer security of the relay system,we propose a jamming aided decodeand-forward relay(JDFR)scheme combining the use of artificial noise and DF relaying which requires two stages to transmit a ***,in stage one,the source sends confidential message to the relay while the destination acts as a friendly jammer and transmits artificial noise to confound the *** stage two,the relay forwards its re-encoded message to the destination while the source emits artificial noise to confuse the *** addition,we analyze the security-reliability tradeoff(SRT)performance of the proposed JDFR scheme,where security and reliability are evaluated by deriving intercept probability(IP)and outage probability(OP),*** the purpose of comparison,SRT of the traditional decode-and-forward relay(TDFR)scheme is also *** results show that the SRT performance of the proposed JDFR scheme is better than that of the TDFR ***,it is shown that for the JDFR scheme,a better SRT performance can be obtained by the optimal power allocation(OPA)between the friendly jammer and user.

关键词： decode-and-forward relay friendly jammer physical layer security power allocation security-reliability tradeoff

Multiple gaseous reduction of ilmenite: thermodynamic and experimental study

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Rare Metals 2015年第12期34卷 888-894页

作者： Wei Xiao Xiong-Gang Lu xing-li zou Chong-He li Wei-Zhong Ding Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University

In this paper, the thermodynamics of the reduction of ilmenite using multiple gases (H2/CO) was calculated. It is found that the metallization rate of 20.1%–98.8%, H2 consumption rate of 43.0%–99.1%, and carbon deposition amount of 5.7×10?7?0.49mol can be obtained based on the conditions of hydrogen volume fraction of 10%–90% and temperature of 450–1200°C. Experimental study was also carried out using synthetic ilmenite as initial materials and reduced in a static bed reactor at 1100°C. The metallization rate reaches 97% when the multiple gas (70% H2/10% CO/20% Ar) flow rate is 120ml·min?1. A thermogravimetric analyzer was used to measure the variation of sample weight caused by the deposition of solid carbon. The amount of carbon deposited during experiments reaches its maximum while the original hydrogen volume content is 20%. The experimental results are well consistent with the thermodynamic analysis.

关键词： Multiple gases Hydrogen Thermodynamic analysis Direct reduction

Vertical two-dimensional WS_(2)flakes grown on flexible CNT film for excellent electrochemical performance

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Rare Metals 2024年第1期43卷 164-174页

作者： Qian Gong Jing-Yun zou Ming Ren Si-Qi Zhu Yu-Rong Zhou li-Ming Zhao Jian Chen Yu-Long Wu Jiang-Tao Di li-xing Kang Qing-Wen li School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Multifunctional Nanomaterials and Smart Systems Division of Advanced MaterialsSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009China

Soft electrochemical actuators that can generate mechanical motions in response to electrical stimuli can be used as artificial muscles in microscale *** electrode materials are the key component of the electrochemical actuator because they limit the ion diffusion and accumulation processes and thus affect the deformation in fast response-time and potential engineering ***-dimensional materials,such as one-dimensional(1D)CNT and two-dimensional(2D)vertically stood WS_(2),are great electrode due to their good electrochemical stability and high surface-to-volume ratios,but show limited performances when being used on their own in the actuators because of low reconstruction or low conductivity.A combination of 1D CNT and 2D WS_(2)could form a heterojunction with both high electrochemical activity and great mechanical ***,by depositing highly disordered graphene nanosheets(HDGNs)on CNT films and then WS_(2)on the formed low-dimensional nanocarbon film,a hybrid WS_(2)/HDGN/CNT film was synthesized through a multistep CVD *** grown WS_(2)nanosheets were achieved by taking advantage of HDGNs which limits CNTs ***,the volume expansion caused by the transition from WO_(3)to WS-2can force the vertical growth of WS_(2).This hybrid film shows excellent electrochemical properties,such as high specific capacitance and high rate *** actuators based on the WS_(2)/HDGN/CNT films show good actuating performance,including stability and reconfigurability.

关键词： CNT Graphene Vertically growth WS_(2) Electrochemical actuators

Syntheses of new di-nuclear and tetra-nuclear lanthanide 9-anthracenecarboxylates:Magnetocaloric effect,slow magnetic relaxation and luminescent properties

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Journal of Rare Earths 2024年第6期42卷 1101-1109,I0004页

作者： xing liu Ruonan Yang Lu Zhang Jian Zhou Chunmei Huang Huahong zou Zunhong Xiao Chongqing Key Laboratory of Inorganic Functional Materials College of ChemistryChongqing Normal UniversityChongqing401331China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China) School of Chemistry and Chemical Engineering of Guangxi Normal UniversityGuilin541004China School of Chemistry and Materials Guizhou Normal UniversityGuiyang550025China

Lanthanide complex-based materials with magnetic and luminescent properties have received a great deal of attention,owing to their importantly potential applications in diverse *** this work,the 9-anthracenecarboxylic acid(9-Haca)as bridging ligand was applied in combination with optically activeπ-conjugated 2,4,6-tri(2-pyridyl)-1,3,5-triazine(tptz)to construct a series of new di-nuclear and tetranuclear lanthanide 9-anthracenecarboxylates[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]·0.25H_(2)O(1),[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]·0.5AQ·CH_(3)COOH_(2)H_(2)O[Ln=Sm(2a),Eu(2b),Gd(2c),Tb(2d),Dy(2e),Tm(2f);AQ=9,10-anthracenedione]and[Ln_(4)(9-aca)_(10)(tptz)_(2)(CH3COO)2]·H_(2)O[Ln=Eu(3a),Gd(3b),Dy(3c)].1 displays a di-nuclear centrosymmetric moiety[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]built up from two complex[La(9-aca)_(2)(tptz)]groups bridged by one H_(2)O molecule and two syn-syn-μ2-η1:η1-9-aca-bridging ligands,while 2a-2f are isostructural and co mprise another di-nuclear centrosymmetric moieties[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]based on two complex[Ln(9-aca)_(2)(tptz)(H_(2)O)]groups connected by two syn-syn-μ2-η1:η1-9-aca-bridging ligands,3a-3c are isostructural and show tetra-nuclear centro symmetric moieties[Ln4(9-aca)10(tptz)2(CH3COO)2]containing three types of coordination modes of *** present compounds offer the only examples of lanthanide 9-anthracenecarboxylates decorated by optically active *** investigations of 2a,2c-2f,and 3b-3c indicate that 3c is typical of slow relaxation of the magnetization,while 2c and 3b show significant magnetocaloric effect(MCE)with the value of-ΔSm of 5.26 J/(kg·K)at 4 K and 15.65 J/(kg·K)at 2 K(ΔH=7 T),*** luminescent properties were also studied and reveal that the characteristic luminescent properties of the 7r-conjugated aromatic ligands are introduced into magnetic lanthanide 9-anthracenecarboxylates,simultaneously exhibiting slow magnetic relaxation(or MCE)and luminescen

关键词： Lanthanide complexes Luminescence Magnetic properties Magnetocaloric effect Slow magnetic relaxation Rare earths

Vibration harmonic suppression technology for electromagnetic vibrators based on an improved sensorless feedback control method

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 472-483页

作者： Wei li Junning CUI xingyuan BIAN limin zou Centerof Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of TechnoogyHarbin 0080China Key Lab of Ultra-precision Intlligent Instrumentation(Harbin Institute of Technology).Ministry of Industry and Information Technology Harbin 150080China

To realize low harmonic distortion of the vibration waveform output from electromagnetic vibrators,we propose a vibration harmonic suppression technology based on an improved sensorless feedback control *** changing the original driving circuit,the alternating current(AC)equivalent resistance of the driving coil is used to obtain high-precision vibration velocity information,and then a simple and reliable velocity feedback control system is *** the study of the effect of different values of key parameters on the system,we have achieved an effective expansion of the velocity characteristic frequency band of low-frequency vibration,resulting in an enhanced harmonic suppression capability of velocity feedback *** present extensive experiments to prove the effectiveness of the proposed method and make comparisons with conventional control *** the frequency range of 0.01-1.00 Hz,without using any sensors,the method proposed in this study can reduce the harmonic distortion of the vibration waveform by about 40%compared to open-loop control and by about 20%compared to a conventional sensorless feedback control method.

关键词： Vibration calibration Electromagnetic vibrators Harmonic suppression Sensorless control method Velocity feedback control

Molecular analyses display the increasing diversity of Podostemaceae in China

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Plant Diversity 2024年第3期46卷 421-424页

作者： Zhi-Zhong li Zhun Xu Shuang Wu Lang-xing Yuan Chun-Yu zou Yan liu Jian-Yong lin Shi-Chu liang Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541006China Wuhan Botanical Garden Chinese Academy of SciencesWuhan 430074China Sino-Africa Joint Research Center Chinese Academy of SciencesWuhan 430074China Guangxi Association for Science and Technology Nanning 530023China Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural SciencesHaikou 571101China Guangxi Institute of Botany Chinese Academy of SciencesGuilin 541006China Guangxi Forestry Research Institute Nanning 530028China

Podostemaceae(riverweed family),one of the largest aquatic plant families in the world,comprises about 350 species in 51 genera placed in three subfamilies,Podostemoideae,Weddellinoideae,and Tristichoideae(Koi et al.,2022).Most Podostemaceae genera(~38)are monotypic or oligotypic,with a high level of endemism(Koi et al.,2018,2022).Members of Podostemaceae adhere to rocks in fast-flowing rivers,streams,or waterfalls in the subtropics and tropics(Koi et al.,2018).As an adaptation to fastrunning currents,the morphological structure of river-weeds tends to be extremely reduced,including a loss or reduction of primary shoots or roots(Koi and Kato,2007).The vegetative mass of these plants resembles lichens or bryophytes,and are thus known commonly as“dream bryophytes”(Philbrick and Retana,1998).Podostemaceae plants flower when the water level drops during the dry *** recent years,anthropogenic factors and climate change have severely affected river weed habitats,decreasing populations of these plants.

关键词： roots season habitat

Real-time Energy Management Method for Electric-hydrogen Hybrid Energy Storage Microgrids Based on DP-MPC

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 324-336页

作者： Qi li Xueli zou Yuchen Pu Weirong Chen School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China

With the increasing presence of intermittent energy resources in microgrids,it is difficult to precisely predict the output of renewable resources and their load *** order to realize the economical operations of the system,an energy management method based on a model predictive control(MPC)and dynamic programming(DP)algorithm is *** method can reasonably distribute the energy of the battery,fuel cell,electrolyzer and external grid,and maximize the output of the distributed power supply while ensuring the power balance and cost optimization of the *** on an ultra-shortterm forecast,the output power of the photovoltaic array and the demand power of the system load are *** offline global optimization of traditional dynamic programming is replaced by the repeated rolling optimization in a limited period of time to obtain power values of each unit in the energy storage *** with the traditional DP,MILP-MPC and the logic based real-time management method,the proposed energy management method is proved to be feasible and effective.

关键词： Electric-hydrogen hybrid energy economic energy management improved dynamic programming microgrid model predictive control

Distributed Predefined-Time Control for Cooperative Tracking of Multiple Quadrotor UAVs

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2179-2181页

作者： Kewei Xia Xinyi li Kaidan li Yao zou Advanced Research Institute of Multidisciplinary Sciences Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering and also with the Advanced Research Institute of Multidisciplinary SciencesBeijing Institute of TechnologyBeijing 100081China the School of Automation Beijing Institute of TechnologyBeijing 100081China the School of Intelligence Science and Technology and also with the Key Laboratory of Intelligent Bionic Unmanned SystemsMinistry of EducationUniversity of Science and Technology BeijingBeijing 100083China

Dear Editor,This letter addresses the predefined-time control for cooperative tracking of multiple quadrotor unmanned aerial vehicles(UAVs)under a directed communication network.A predefined-time distributed estimator... 详细信息

关键词： acceleration letter estimator

Boosting Hydrogen Storage Performance of MgH_(2) by Oxygen Vacancy-Rich H-V_(2)O_(5) Nanosheet as an Excited H-Pump

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Nano-Micro Letters 2024年第8期16卷 398-416页

作者： li Ren Yinghui li Zi li Xi lin Chong Lu Wenjiang Ding Jianxin zou National Engineering Research Center of light Alloys Net Forming&State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Engineering Research Center of Mg Materials and Applications&School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Center of Hydrogen Science Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Instrumental Analysis Center of SJTU Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

MgH_(2) is a promising high-capacity solid-state hydrogen storage material,while its application is greatly hindered by the high desorption temperature and sluggish ***,intertwined 2D oxygen vacancy-rich V_(2)O_(5) nanosheets(H-V_(2)O_(5))are specifically designed and used as catalysts to improve the hydrogen storage properties of MgH_(2).The as-prepared MgH_(2)-H-V_(2)O_(5) composites exhibit low desorption temperatures(Tonset=185℃)with a hydrogen capacity of 6.54 wt%,fast kinetics(Ea=84.55±1.37 kJ mol^(-1) H_(2) for desorption),and long cycling ***,hydrogen absorption can be achieved at a temperature as low as 30℃ with a capacity of 2.38 wt%within 60 ***,the composites maintain a capacity retention rate of~99%after 100 cycles at 275℃.Experimental studies and theoretical calculations demonstrate that the in-situ formed VH_(2)/V catalysts,unique 2D structure of H-V_(2)O_(5) nanosheets,and abundant oxygen vacancies positively contribute to the improved hydrogen sorption ***,the existence of oxygen vacancies plays a double role,which could not only directly accelerate the hydrogen ab/de-sorption rate of MgH_(2),but also indirectly affect the activity of the catalytic phase VH_(2)/V,thereby further boosting the hydrogen storage performance of MgH_(2).This work highlights an oxygen vacancy excited“hydrogen pump”effect of VH_(2)/V on the hydrogen sorption of Mg/MgH_(2).The strategy developed here may pave a new way toward the development of oxygen vacancy-rich transition metal oxides catalyzed hydride systems.

关键词： Hydrogen storage MgH_(2) V_(2)O_(5)nanosheets Oxygen vacancies VH_(2)