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TM polarization characteristics on thermal radiation of a negative refractive index thin film

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Chinese Science Bulletin 2009年第10期54卷 1663-1668页

作者： CUl Yi HUANG yong li wen WAN Jun School of Aeronautical Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Thermal radiation TM polarization characteristics of a negative refractive index thin film was studied based on the transmit matrix method and Kirchhoff radiation law. The influence of the thin film pa- rameters on the thermal radiation directional characteristics and spectral property were discussed. And the influence of the evanescent waves was also discussed. The results show that two factors play important roles in the thermal radiation of negative index thin film: one is the interference effect of the thin film structure to the electromagnetic waves; the other is the photon tunneling effect of the negative refractive index material, which was caused by the amplifying evanescent wave. These indicate that spectral and directional characteristics of the thermal emissivity can be modulated by modifying the structure and the physics parameters of the negative refraction index thin film.

关键词：薄膜参数负折射率偏振特性热辐射商标光子隧道效应光谱性质方向特性

Increasing the efficiency of post-selection in direct measurement of the quantum wave function

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Chinese Physics B 2022年第3期31卷 285-291页

作者： yong-li wen Shanchao Zhang Hui Yan Shi-liang Zhu National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Direct weak or strong measurement of quantum wave function based on post-selections has been widely explored;however, the efficiency of the measurement is heavily limited by the success probability of post-selection. Here we propose a modified scheme to directly measure photon’s wave function by simply inserting a liquid crystal plate before the postselection stage. Numerical simulations demonstrate that our modified method can significantly increase the efficiency of post selection. Our proposal would speed up the quantum wave function measurement with high resolution and high fidelity.

关键词： weak measurement quantum state

Constructing lithium-Free Anode/Separator Interface via 3D Carbon Fabric Scaffold for Ultrasafe lithium Metal Batteries

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Research 2024年第3期2023卷 359-368页

作者： Dongdong li Shengchen Yang Zijian Zheng wen-yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China Department of Materials Chemistry Huzhou University1 Xueshi RoadHuzhou 313000China Laboratory for Advanced Interfacial Materials and Devices School of Fashion and TextilesDepartment of Applied Biology and Chemical TechnologyResearch Institute for Intelligent Wearable Systems(RI-IWEAR)Research Institute for Smart Energy(RISE)The Hong Kong Polytechnic UniversityHong Kong SAR 999077China

Metallic lithium represents a promising anode candidate to be utilized in future high-energy lithium ***,the undesirable dendrite growth and fragile solid-electrolyte interphase(SEI)pose critical challenge for pursuing further practical *** contrast to traditional approaches of using inert/lithiophilicity coating,here,we demonstrate a reverse strategy of introducing a highly conductive and lithophobic carbon fabric(CF)scaffold on lithium foil to guide a favorable nucleation site of lithium far away from the anode/separator *** CF scaffold with high conductivity can couple with inner electric field for achieving a uniform distribution of the lithium-ion flux,while the lithophobic feature offers the condition to guide the preferred deposition of lithium onto the underlying lithium foil,which greatly reduces the risk of dendrite-induced short ***,the SEI immersed in the CF scaffold is well supported by CF fibers and therefore exhibits extremely high stability during charge–discharge *** a result,the lithium/CF anodes show>2,000-h stable cycling at 0.5 mA cm−*** metal batteries equipped with our lithium/CF anode deliver a high capacity retention of~99.99%per cycle,i.e.,retain~97.3%capacity after 200 *** unique interface-regulation strategy is versatile for various conductive scaffolds(e.g.,ultrathin and ultralight conductive fabrics),exhibiting high superiority for highly safe lithium metal batteries.

关键词： lithium equipped versatile

Interplay between geometric and electronic structures of Pt entities over TiO_(2) for CO oxidation

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Science China Chemistry 2024年第2期67卷 705-714页

作者： Xixiong Zhang wen Shi Shaobo Han yong li wenjie Shen School of Chemistry Dalian University of TechnologyDalian116024China State Key Laboratory of Catalysis Dalian Institution of Chemical PhysicsChinese Academy of SciencesDalian116023China

Monodispersed Pt colloids with a mean size of 2 nm were deposited uniformly on the {110} facets of a rod-shaped rutile TiO_(2),forming a well-defined Pt/TiO_(2) *** treatment of this precursor at elevated temperatures re-dispersed the Pt particles into clusters and ***-calcination at 673 K partially oxidized the Pt particle surface,while calcination at 773 K yielded Pt Oxclusters of 1.6 nm in 7–8 atomic *** calcination at 873 K formed a mixture of raft-like PtO_(x) clusters(1.6 nm,1–2 atomic layers) and cationic *** tested for CO oxidation at 373 K,the Pt particles showed a higher activity than the Pt Oxclusters,whereas the cationic single-atoms were much less *** H_(2)-reduction at 473 K converted the partially oxidized Pt particles into the metallic species,but they were encapsulated by TiO_(2)–xoverlayers because of the strong metal–support interactions,which decreased the activity dramatically.H_(2)-reduction of the PtO_(x) clusters at473 K enhanced the fraction of metallic Pt species without changing the size and geometry,and promoted the activity substantially.H_(2)-treatment of Pt single-atoms at 473 K increased the activity only moderately because most Pt species still kept at cationic *** results straightforwardly differentiated the catalytic behavior of Pt particles,clusters and single-atoms at the same metal loading and over the same TiO_(2) support,and further demonstrated that the electronic structures of Pt entities played a decisive role in the catalytic oxidation,in addition to the specified sizes.

关键词： Pt/TiO_(2)catalyst size effect Pt clusters active sites electronic structures CO oxidation

State of the art of lightweight aggregates used in lightweight refractories for working lining of high-temperature furnaces

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Journal of Iron and Steel Research International 2024年第6期31卷 1320-1343页

作者： Wei Zhang wen-yong Dai Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Research and Development Department AGC Plibrico(Dalian)Industries Inc.Dalian 116600LiaoningChina

lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and *** prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the ***,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread *** available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based ***,the future development trend of lightweight aggregates was proposed.

关键词： lightweight aggregate lightweight refractory Working lining Apparent porosity Closed porosity Thermal conductivity Pore-forming approach

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： yong YANG Ren-Sheng CHEN yong-Jian DING Hong-Yuan li Zhang-wen liU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

Convex Optimization Algorithms for Cooperative Localization in Autonomous Underwater Vehicles

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自动化学报 2010年第5期36卷 704-710页

作者： liU Ming-yong li wen-Bai PEI Xuan College of Marine Northwestern Polytechnical University Xi'an 710072 P. R. China

In this paper, a cooperative localization algorithm for autonomous underwater vehicles (AUVs) is proposed. A “parallel” model is adopted to describe the cooperative localization problem instead of the traditional “leader-follower” model, and a linear programming associated with convex optimization method is used to deal with the problem. After an unknown-but-bounded model for sensor noise is assumed, bearing and range measurements can be modeled as linear constraints on the configuration space of the AUVs. Merging these constraints induces a convex polyhedron representing the set of all configurations consistent with the sensor measurements. Estimates for the uncertainty in the position of a single AUV or the relative positions of two or more nodes can then be obtained by projecting this polyhedron onto appropriate subspaces of the configuration space. Two different optimization algorithms are given to recover the uncertainty region according to the number of the AUVs. Simulation results are presented for a typical localization example of the AUV formation. The results show that our positioning method offers a good localization accuracy, although a small number of low-cost sensors are needed for each vehicle, and this validates that it is an economical and practical positioning approach compared with the traditional approach.

关键词：最优化自动化系统自适应系统 AUV

Effects of Total Alkaloids in Buxus microphylla Leaves on Aorta Smooth Muscle of Rats and Their Mechanisms

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Chinese Herbal Medicines 2012年第2期4卷 136-141页

作者： Hui-qin ZHANG[a] Yan-yan liU[b] yong-wen li[a] li li[a] Zhi-qing CUI[c] Department of Pharmacology Guilin Medical College Guilin 541001 China

Objective To investigate the effects of total alkaloids in Buxus microphylla leaves(ABML)on isolated rats thoracic aorta rings,and then to explore the possible mechanisms underlying the *** Thoracic aortas of Wistar rats were isolated,removed,and mounted onto an organ *** effects of ABML at different concentration on the contraction of isolated thoracic aorta rings(with and without endothelium)precontracted with KCl or PE were observed with organ bath ***-effect curves of CaCl2 were recorded by organ bath *** concentration of intracellular Ca 2+ ([Ca 2+ ]i)increased by PE,KCI,and caffeine in the presence of ABML was determined using Ca 2+ sensitive fluorescence indicator Fura-2/AM loaded thoracic aorta vascular smooth muscle (VSM)cells of *** In aorta rings precontracted with PE and KCl,ABML produced concentration- dependent relaxation in both intact and denuded endothelium ring *** was no difference in the inhibition of contraction between the intact and denuded endothelium ring groups at the same *** of isolated thoracic aorta rings to ABML led to a significant reduction in the contracting response induced by CaCl2,and shifted the cumulative concentration-response curves to *** could significantly inhibit the extracellular Ca 2+ influx induced by PE and KCl under[Ca 2+ ]0 of 1.5 mmol/L,with inhibitory ratios of 40.2%and 49.9%,*** the case of Ca 2+ -free,ABML could significantly inhibit the intracellular Ca 2+ release induced by PE,with inhibitory ratio of 72.4%.Conclusion ABML relaxes thoracic aorta VSM cells by suppressing influx of extracellular Ca 2+ via voltage-dependent Ca 2+ channel and receptor-operated Ca 2+ channel.

关键词： Ca 2+ Fura-2/AM isolated thoracic aorta rings total alkaloids of Buxus microphylla leaves vascular smooth muscle cells

PMAC-based Tracking Control System for 8-axis Automated Tape-laying Machine

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Chinese Journal of Aeronautics 2009年第5期22卷 558-563页

作者： liu lin li yong wen liwei Xiao Jun College of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article introduces a computer numerical control （CNC）-based open hardware architecture system to realize the special functions of automated tape-laying （ATL） in a numerical control system. It associates a programmable multi-axis controller （PMAC） as the motion control unit with programmable numerical controllers （PCL-725, PCL-730） for on-off control. To bring about synchronized movements of the main 5-axis tape-laying head system and the 3-axis ultrasonic tape-cutting sub-system, the tracking-control method associated with time-based mode attributed to PMAC is applied in different cases. In addition, with the goal of realizing real-time tasks in the software system such as synchronizing motion control and on-off control, the real-time Win 2000 system is adopted. As a device driver for PMAC and PCL, a user graphical interface and a numerical control program interpretation module are also designed. This system is helpful to solve complicated problems in designing numerical controls for ATL such as ensuring high requirements for precise machine control and synchronization of motion control and on-off control.

关键词： automated tape-laying tape-cutting programmable multi-axis controller on-off control systems tracking control