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Rechargeable metal(Li, Na, Mg, Al)-sulfur batteries: Materials and advances

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Journal of Energy Chemistry 2021年第10期30卷 104-134,I0004页

作者： xue Liu Yan Li xu xu Liang Zhou Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070HubeiChina Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200GuangdongChina

Energy and environmental issues are becoming more and more severe and renewable energy storage technologies are vital to solve the *** metal(Li,Na,Mg,Al)-sulfur batteries with low-cost and earth-abundant elemental sulfur as the cathode are attracting more and more interest for electrical energy storage in recent ***-sulfur(Li-S),room-temperature sodium-sulfur(RT Na-S),magnesium-sulfur(Mg-S)and aluminum-sulfur(Al-S)batteries are the most prominent candidates among *** obvious obstacles are hampering the developments of metal-sulfur ***-S and Na-S batteries are encumbered mainly by anode dendrite issues,polysulfides shuttle and low conductivity of ***-S and Al-S batteries are short of suitable *** this review,relationships between various employed nanostructured materials and electrochemical performances of metal-sulfur batteries have been ***,the selections of suitable electrolytes,anode protection,separator modifications and prototype innovations are all crucial to the developments of metal-sulfur batteries and are discussed at the same ***,we give a review on the advances of Li-S,RT Na-S,Mg-S and Al-S batteries from the point of view of materials,and then focus on perspectives of their future developments.

关键词： Lithium sulfur batteries Sodium sulfur batteries Magnesium sulfur batteries Aluminum sulfur batteries Energy materials

Fabrication and Microwave Absorption Properties of Fe_(0.64)Ni_(0.36)-NiFe_2O_4 Nanocomposite

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Nano-Micro Letters 2012年第3期4卷 176-179页

作者： xu Yan Desheng xue Key Laboratory for Magnetism and Magnetic Materials of the ministry of Education Lanzhou University

Fe_(0.64)Ni_(0.36)-NiFe_2O_4 nanocomposite was performed with partially reducing NiFe_2O_4 nanoparticles in Ar/H_2 *** microwave and static magnetic properties were *** results showed that the nanocomposite was characterized with enhanced microwave absorption *** optimal reflection loss(RL)of the nanocomposite reached-24.8 dB at 14 GHz for an absorber thickness of 1.5 ***,a broad bandwidth for RL<-10 dB was obtained in the range of 3.1—15.1 GHz for an absorber thickness from1.0 to 4.0 *** enhancement is attributed to the increase of dielectric and magnetic loss after reducing procedure.

关键词： Fe0.64Ni0.36/NiFe2O4 Nanoparticles Microwave

On pricing of corporate securities in the case of jump-diffusion

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Applied Mathematics(A Journal of Chinese Universities) 2014年第2期29卷 205-216页

作者： REN xue-min JIANG Li-shang Department of Mathematics Tongji University

Structural models of credit risk are known to present vanishing spreads at very short maturities. This shortcoming, which is due to the diffusive behavior assumed for asset values, can be circumvented by considering discontinuities of the jump type in their evolution over time. In this paper, we extend the pricing model for corporate bond and determine the default probability in jump-diffusion model to address this issue. To make the problem clearly, we first investigate the case that the firm value follows a geometric Brownian motion under similar assumptions to those in Black and Scholes（1973）, Briys and de Varenne（1997）, i.e, the default barrier is KD （t, T） and the recovery rate is （1 -w）, where D （t, T） is the price of zero coupon default free bond and w is a constant （0 〈 w 〈 1）. By changing the numeraire, we obtain the closed-form solution for both the price of bond and default probability. Further, we consider the case of jump-diffusion and suppose that a firm will go bankruptcy if its value Vt 〈 KD （t, T） and at the same time, the bondholder will receive （1 - w） vt/k By introducing the Green function of PDE with absorbing boundary and converting the problem to an II-type Volterra integral equation, we get the closed-form expressions in series form for bond price and corresponding default probability. Numerical results are presented to show the impact of different parameters to credit spread of bond.

关键词： default risk corporate bond stochastic interest rate jump diffusion process.

Multi-dimensional, light-controlled switch of fluorescence resonance energy transfer based on orderly assembly of 0D dye@micro-micelles and 2D ultrathin-layered nanosheets

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Nano Research 2016年第12期9卷 3828-3838页

作者： Zhixiong Li Ruizheng Liang Simin xu Wendi Liu Dongpeng Yan min Wei David G. Evans xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Fluorescence resonance energy transfer （FRET） systems have broad applications in visual detection, intelligent materials, and biological imaging, all of which favor the transmission of light through multiple dimensions and in diverse directions. Herein, we have demonstrated multi-dimensional （0D and 2D） FRET within a multi-layer ultrathin film （UTF） by employing a layer-by-layer （LBL） assembly technique. The anionic block copolymer micelle poly（tert-butyl acrylate- co-ethyl acrylate-co-methacrylic acid）（PTBEM） is chosen as a molecular carrier for the incorporation of bis（8-hydroxyquinolate） zinc （Znq2） and open-ring merocyanine （MC）（denoted as （Znq2/MC）@PTBEM）. Alternatively, electrostatic assembly is performed with cationic layered double hydroxide （LDH） nanosheets （denoted as [（Znq2/MC）@PTBEM/LDH]n）. This [（Znq2/MC）@PTBEM/ LDH]n system offers a multi-dimensional propagation medium and ensures that the FRET donor and acceptor are located within their F6rster radii in each direction. The system demonstrates a FRET process that can be switched via alternating ultraviolet/visible （UV/vis） irradiation, with tunable blue-green/red fluorescence, resulting in a FRET efficiency as high as 81.7%. It is expected that this assembly method, which uses 0D micelles on a 2D layered material, can be extended to other systems for further development of multi-dimensional FRET.

关键词： bis(8-hydroxyquinolate)zinc (Znq2) open-ring merocyanine layered double hydroxide layer-by-layerself-assembly multi-dimensionalfluorescence resonanceenergy transfer

Finite element analysis of 2D SMA beam bending

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Acta Mechanica Sinica 2011年第5期27卷 738-748页

作者： Shi-Bin Yang min xu Aircraft Airworthiness Certification Research Center Civil Aviation University of China300300 Tianjin China Department of Astronautics Northwestern Polytechnical University710072 Xi＇an China

A thermomechanical model of a shape memory alloy beam bending under tip force loading is implemented in finite element *** constitutive model is a one dimensional model which is based on free energy and motivated by statistical *** particular focus of this paper is on the aspects of finite element modeling and simulation of the inhomogeneous beam bending *** paper extends previous work which is based on the small deformation Euler-Bernoulli beam theory and by treating an SMA beam as consisting of multi-layers in a twodimensional *** flux terms are involved in the heat transfer *** simulations can represent both shape memory effect and super-elastic *** thermal boundary condition effect and load rate effect can also be captured.

关键词： Shape memory alloy SMA cantilever beam Thermomechanical Martensitic transformation Finite element analysis

Autonomous Formation Flight Control of Large-Sized Flapping-Wing Flying Robots Based on Leader–Follower Strategy

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Journal of Bionic Engineering 2023年第6期20卷 2542-2558页

作者： Hui xu Yuanpeng Wang Erzhen Pan Wenfu xu Dong xue School of Mechanical Engineering and Automation Harbin Instwitute of TechnologyShenzhen518055China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150000China School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China

Birds in nature exhibit excellent long-distance flight capabilities through formation flight,which could reduce energy consumption and improve flight *** by the biological habits of birds,this paper proposes an autonomous formation flight control method for Large-sized Flapping-Wing Flying Robots(LFWFRs),which can enhance their search range and flight ***,the kinematics model for LFWFRs is ***,an autonomous flight controller based on this model is designed,which has multiple flight control modes,including attitude stabilization,course keeping,hovering,and so ***,a formation flight control method is proposed based on the leader–follower strategy and periodic characteristics of flapping-wing *** up and down fluctuation of the fuselage of each LFWFR during wing flapping is considered in the control algorithm to keep the relative distance,which overcomes the trajectory divergence caused by sensor delay and fuselage ***,typical formation flight modes are realized,including straight formation,circular formation,and switching ***,the outdoor formation flight experiment is carried out,and the proposed autonomous formation flight control method is verified in real environment.

关键词： Bionic Large-sized flapping-wing flying robot HIT-Phoenix Periodic flight characteristics Formation flight Leader follower strategy

Vertex partitions of r-edge-colored graphs

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 120-126页

作者： JIN Ze-min LI xue-liang Center for Combinatorics and LPMC-TJKLC Nankai University Tianjin 300071 China. Department of Mathematics Zhejiang Normal University Jinhua 321004 China.

Let G be an edge-colored graph. The monochromatic tree partition problem is to find the minimum number of vertex disjoint monochromatic trees to cover the all vertices of G. In the authors＇ previous work, it has been proved that the problem is NP-complete and there does not exist any constant factor approximation algorithm for it unless P= NP. In this paper the authors show that for any fixed integer r ≥ 5, if the edges of a graph G are colored by r colors, called an r-edge-colored graph, the problem remains NP-complete. Similar result holds for the monochromatic path （cycle） partition problem. Therefore, to find some classes of interesting graphs for which the problem can be solved in polynomial time seems interesting. A linear time algorithm for the monochromatic path partition problem for edge-colored trees is given.

关键词： monochromatic tree (path cycle) NP-complete linear time algorithm.

Effect Factors in Synthesis of Nicotinic Acid by Electrooxidation of 3-Picoline

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Chemical Research in Chinese Universities 2005年第6期21卷 692-696页

作者： SUN Xiu-yun ZHANG Yu-min CAO xue-jing ZHANG Heng-bin LI Fei xu Yu-ling College of Chemistry Jilin University Changchun 130021 P. R. China Department of Applied Chemistry Jilin Institute of Chemical Technology Jilin 132022 P. R. China

In an electrolytic cell with a proton exchange membrane, nicotinic acid was synthesized at the PbO2 anode. The relationship between the current density and the potential at different concentrations of 3-picoline and sulfuric acid as well as at different temperatures was studied with polarization curves. The effects of the concentrations of sulfuric acid and 3-picoline, the anode potential and the reaction temperature on the selectivity and the current efficiency were explored. The optimum conditions were determined by orthogonal experiments. Under optimum conditions the selectivity and the current efficiency for the synthesis of nicotinic acid might reach 89% and 65%, respectively. The, concentrations of 3-picoline and nicotinic acid were analyzed with high performance liquid chromatography and the product was characterized with elemental analysis, chromatography-mass spectrometry and IR spectrometry.

关键词： 3-Picoline Nicotinic acid Electrooxidation Electroorganic synthesis

Long-Term Effects of Docosahexaenoic Acid-Bound Phospholipids and the Combination of Docosahexaenoic Acid-Bound Triglyceride and Egg Yolk Phospholipid on Lipid Metabolism in Mice

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Journal of Ocean University of China 2018年第2期17卷 392-398页

作者： CHE Hongxia CUI Jie WEN min xu Jie Teruyoshi Yanagita WANG Qi xue Changhu WANG Yuming College of Food Science and Engineering Ocean University of China Department of Health and Nutrition Science Nishikyushu University College of Food Science and Engineering Wuhan Polytechnic University

The bioavailability of docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA) depends on their chemical forms. This study investigated the long-term effects of DHA-bound triglyceride(TG-DHA), DHA-bound phospholipid(PL-DHA), and the combination of TG-DHA and egg yolk phospholipid(Egg-PL) on lipid metabolism in mice fed with a high-fat diet(fat levels of 22.5%). Male C57BL/6J mice were fed with different formulations containing 0.5% DHA, including TG-DHA, PL-DHA, and the combination of TG-DHA and Egg-PL, for 6 weeks. Serum, hepatic, and cerebral lipid concentrations and the fatty acid compositions of the liver and brain were determined. The concentrations of serum total triglyceride(TG), total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), and hepatic TG in the PL-DHA group and the combination group were significantly lower than those in the high-fat(HF) group(P < 0.05). Atherogenic index(AI) of the PL-DHA group was significantly lower than that of the combination group(P < 0.05). Hepatic TC level in the combination group was significantly lower than that in the HF group(P < 0.05), but no significant difference was observed between the combination group and the PL-DHA group. Both the PL-DHA and the combination groups showed significantly increased DHA levels in the liver compared with the HF group(P < 0.05). However, there were no obvious increases in the cerebral DHA levels in all DHA diet groups. These results suggest that PL-DHA was superior to the combination of TG-DHA and Egg-PL in decreasing the AI. Long-term dietary supplementation with low amount of DHA(0.5%) may improve hepatic DHA levels, although cerebral DHA levels may not be enhanced.

关键词： omega-3 fatty acid docosahexaenoic acid eicosapentaenoic acid lipid metabolism triglycerides phospholipids