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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1354-1363页

作者： jie Chen Chong-Gao Bao yong Wang jin-Ling Liu Challapalli Suryanarayana State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong University State Key Laboratory of Traction Power School of Mechanics and EngineeringSouthwest Jiaotong University Department of Mechanical and Aerospace Engineering University of Central Florida

Magnesium matrix composites reinforced with AlN particles were fabricated by the powder metallurgy technique. The evolution of lattice constants and solid solubility levels of Al in α-Mg and the microstructure of Mg-Al/AlN composites were investigated in the present study. The results showed that the solid solubility of Al in α-Mg reached a relatively high level by the P/M process with a long time of milling. X-ray diffraction showed that the peaks of Mg phase clearly shifted to higher angles. The lattice constants and cell volume decreased significantly compared with those of standard Mg due to a significant amount of Al incorporated into α-Mg in the form of substitutional solid solution. The degree of lattice deformation decreased at a low sintering temperature and increased at higher sintering temperatures due to the presence of AlN. Microstructural characterization of the composites revealed a necklace distribution of AlN particles in the Mg matrix. Heat treatment led to precipitation of Mg17Al12 from the supersaturated α-Mg solid solution. The pre- cipitate exhibited granular and lath-shaped morphologies in Mg matrix and ftocculent precipitation around AlN particles.

关键词： Metal matrix composite AIN particle Microstructure Lattice parameter Powder metallurgy Solid solubility

Electrochemical deposition of uranium oxide with an electrocatalytically active electrode using double potential step technique

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Chinese Chemical Letters 2022年第8期33卷 3762-3766页

作者： jie Huang Zhirong Liu Dejuan Huang Tianxiang jin yong Qian Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China

The development of effective uranium-removal techniques is of great significance to the environment and human *** this work,a double potential step technique(DPST)was applied to remove U(VI)from uranium-containing wastewater using a carbon felt electrode modified by graphene oxide/phytic acid composite(GO-PA@CF).The application of DPST can inhibit water splitting and prevent GO-PA from adsorbing other interfering ions in *** GO-PA composite can effectively accelerate the electrochemical reduction rate of U(VI),which significantly improved the electrochemical deposition rate of uranium *** a result,the maximum removal efficiency and maximum removal capacity of GOPA@CF electrode reached 98.7%and 1149.3 mg/g,*** removal efficiency remained 97.2%after five cycles of ***,the removal efficiency of GO-PA@CF electrode can reach more than 70%in simulated wastewater.

关键词： Electrochemical deposition Uranium Double potential step technique Graphene oxide Nanocomposites

Robust beam splitter with fast quantum state transfer through a topological interface

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Frontiers of physics 2023年第5期18卷 293-309页

作者： Jia-Ning Zhang jin-Xuan Han jin-Lei Wu jie Song yong-Yuan Jiang Department of Optoelectronics Science Harbin Institute of TechnologyWeihai 264209China School of Physics Harbin Institute of TechnologyHarbin 150001China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Key Laboratory of Micro-Nano Optoelectronic Information System Ministry of Industry and Information TechnologyHarbin 150001China Key Laboratory of Micro-Optics and Photonic Technology of Heilongjiang Province Harbin Institute of TechnologyHarbin 150001China

The Su–Schrieffer–Heeger(SSH)model,commonly used for robust state transfers through topologically protected edge pumping,has been generalized and exploited to engineer diverse functional quantum ***,we propose to realize a fast topological beam splitter based on a generalized SSH model by accelerating the quantum state transfer(QST)process essentially limited by adiabatic *** scheme involves delicate orchestration of the instantaneous energy spectrum through exponential modulation of nearest neighbor coupling strengths and onsite energies,yielding a significantly accelerated beam splitting *** to properties of topological pumping and accelerated QST,the beam splitter exhibits strong robustness against parameter disorders and losses of *** addition,the model demonstrates good scalability and can be extended to two-dimensional crossed-chain structures to realize a topological router with variable numbers of output *** work provides practical prospects for fast and robust topological QST in feasible quantum devices in large-scale quantum information processing.

关键词： quantum state transfer beam splitter topological router

Bimetal nanoparticles hybridized with carbon nanotube boosting bifunctional oxygen electrocatalytic performance

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Rare Metals 2022年第8期41卷 2616-2623页

作者： Chen Sun yong-jie Zhao Xuan-Yi Yuan jing-Bo Li Hai-Bo jin Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China Beijing Key Laboratory of Opto-Electronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing100872China

Developing bifunctional oxygen catalysts with high efficiency and low cost to replace platinum-group metal catalysts commonly utilized in metal-air batteries is critically *** this article,a convenient method to synthesis NiFe nanoparticles hybridized with N-doped carbon nanotube(NiFe@N-CNTs)is *** performance analysis indicates that Ni_(x)Fc_(1-x)@N-CNTs offers favorable oxygen reduction reaction(ORR)kinetics(onset potential(E_(onset))is 0.87 V and half-wave potential(E_(1/2))is0.84 V),together with excellent oxygen evolution reaction(OER)performance(an overpotential of 270 mV to drive10 mA·cm^(-2)).Contributed by the synergetic effect between NiFe alloy and N-CNTs,when being utilized as air cathode,rechargeable Zn-air batteries present superior cycling stability for over 150 *** research provides a universal strategy to synthesize the hybrids of intertwined carbon nanotube matrix loaded with alloy nanoparticles.

关键词： NiFe alloy Oxygen evolution reaction(OER) Oxygen reduction reaction(ORR) Zn-air batteries

Quartz luminescence dating of a centennial coastal foredune from Changle in Fujian Province,East China Sea

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Journal of Mountain Science 2022年第9期19卷 2601-2610页

作者： jin Jian-hui LI Zhi-zhong LING Zhi-yong QIU Jun-jie Key Laboratory for Subtropical Resources and Environment of Fujian Province Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China Qinghai Institute of Salt Lakes Chinese Academy of SciencesXi'ning 810008China

The Aeolian foredunes in the southern coast of China are records of paleoenvironmental changes for marine monsoon region. Intensive studies have been conducted to decipher their formation and paleoenvironmental implications in which chronology played a key role. However, robust dating results are still limited due to the scarcity of organic materials for radiocarbon and the limited application of quartz optically stimulated luminescence(OSL). Here, we collected 11 OSL samples and 140 grainsize samples from the Changle section with a thickness of 7 m from a coastal foredune in Fujian Province. The dating results indicated that the section spanned a time period from 0.32±0.04 ka(depth of 700 cm) to 0.18±0.02 ka(depth of 80 cm), after removal of age outliers. According to the OSL ages and sedimentary structural characteristics, the section could be divided into two stages, i.e. the stable accumulation period with an age range of 0.32-0.18 ka from the depth of 700 cm to 80 cm, and the activation period above the depth of 60 cm, at which the dune erosion was retained. The foredune development due to increased transport of dune sediment at the top part of the section was the result of recent human *** the foredunes, normal cross-bedding was generated by seasonal changes in wind *** changes in the wind direction were the primary cause for various sedimentary bedding within the dunes.

关键词： Optically stimulated luminescence Grain size Oblique foredune Coastal South China

Traffic dynamics considering packet loss in finite buffer networks

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Chinese Physics B 2019年第4期28卷 433-438页

作者： jie Chen jin-yong Chen Ming Li Mao-Bin Hu School of Engineering Science University of Science and Technology of China Civil Architectural and Environmental Engineering University of Texas at Austin

In real complex systems, the limited storage capacity of physical devices often results in the loss of data. We study the effect of buffer size on packet loss threshold in scale-free networks. A new order parameter is proposed to characterize the packet loss threshold. Our results show that the packet loss threshold can be optimized with a relative small buffer size. Meanwhile, a large buffer size will increase the travel time. Furthermore, we propose a Buffered-Shortest-Path-First(BSPF) queuing strategy. Compared to the traditional First-In-First-Out(FIFO) strategy, BSPF can not only increase the packet loss threshold but can also significantly decrease the travel length and travel time in both identical and heterogeneous node capacity cases. Our study will help to improve the traffic performance in finite buffer networks.

关键词： finite buffer networks loss threshold queuing strategy

Implementation procedure for the generalized moving Preisach model based on a first order reversal curve diagram

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Rare Metals 2009年第4期28卷 355-360页

作者： HAN yong ZHU jie State Key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

First order reversal curves （FORC） of nanocomposite Nd2Fe14B/Fe3B magnetic materials were measured to attain a FORC diagram, which characterizes reversible magnetization, irreversible magnetization, and magnetic interactions in a hysteresis system. Then, generalized mov- ing Preisach model （GMPM） was implemented based on the FORC diagram. Reversible and irreversible magnetizations shown in FORCs and a FORC diagram were used as an input of GMPM. Coupling interaction between reversible and irreversible magnetizations was added when calculating reversible magnetization. Meanwhile, irreversible magnetic moments＇ interaction was approximately represented by mean field interaction. The result shows that the simulated main curves mostly coincide with the experimental curves.

关键词： FORC diagram Preisach model reversible magnetization irreversible magnetization magnetic interactions

Pretreatment with H_2O_2 Alleviates Aluminum-induced Oxidative Stress in Wheat Seedlings

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Journal of Integrative Plant Biology 2011年第1期53卷 44-53页

作者： Fang jie Xu Chong Wei jin Wen jing Liu yong Song Zhang Xian yong Lin Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental & Resource Sciences Zhejiang University Hangzhou 310029 China Zhejiang Key Laboratory of Subtropical Soil Science and Plant Nutrition College of Environmental & Resources Science Zhejiang University Hangzhou 310029 China

Hydrogen peroxide （H2O2） is a key reactive oxygen species （ROS） in signal transduction pathways leading to activation of plant defenses against biotic and abiotic stresses. In this study, we investigated the effects of H2O2 pretreatment on aluminum （AI） induced antioxidant responses in root tips of two wheat （Triticum aestivum L.） genotypes, Yangmai-5 （AI-sensitive） and Jian-864 （AI-tolerant）. AI increased accumulation of H2O2 and O2^- leading to more predominant lipid peroxidation, programmed cell death and root elongation inhibition in Yangmai-5 than in Jian-864. However, H2O2 pretreatment alleviated AI- induced deleterious effects in both genotypes. Under AI stress, H2O2 pretreatment increased the activities of superoxide dismutase, catalase, peroxidase, ascorbate peroxidase and monodehydroascorbate reductase, glutathione reductase and glutathione peroxidase as well as the levels of ascorbate and glutathione more significantly in Yangmai-5 than in Jian-864. Furthermore, H2O2 pretreatment also in- creased the total antioxidant capacity evaluated as the 2, 2-diphenyl-l-picrylhydrazyl-radical scavenging activity and the ferric reducing/antioxidant power more significantly in Yangmai-5 than in Jian-864. Therefore, we conclude that H2O2 pretreatment improves wheat AI acclimation during subsequent AI exposure by enhancing the antioxidant defense capacity, which prevents ROS accumulation, and that the enhancement is greater in the AI-sensitive genotype than in the AI-tolerant genotype.

关键词： WHEAT OXIDATIVE stress HYDROGEN peroxide PLANT defenses EFFECT of aluminum on plants BIOACCUMULATION SEEDLINGS

Fast topological pumping for the generation of large-scale Greenberger–Horne–Zeilinger states in a superconducting circuit

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Frontiers of physics 2022年第6期17卷 143-161页

作者： jin-Xuan Han jin-Lei Wu Zhong-Hui Yuan Yan Xia yong-Yuan Jiang jie Song School of Physics Harbin Institute of TechnologyHarbin 150001China Department of Optoelectronics Science Harbin Institute of TechnologyWeihai 264209China Department of Physics Fuzhou UniversityFuzhou 350002China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Key Laboratory of Micro-Nano Optoelectronic Information System Ministry of Industry and Information TechnologyHarbin 150001China Key Laboratory of Micro-Optics and Photonic Technology of Heilongjiang Province Harbin Institute of TechnologyHarbin 150001China

Topological pumping of edge states in the finite lattice with nontrivial topological phases provides a powerful means for robust excitation transfer,requiring extremely slow evolution to follow an adiabatic ***,we propose fast topological pumping via edge channels to generate large-scale Greenberger–Horne–Zeilinger(GHZ)states in a topological superconducting circuit with a sped-up evolution *** scheme indicates a conceptual way of designing fast topological pumping related to the instantaneous energy spectrum characteristics rather than relying on the shortcuts to *** on fast topological pumping,large-scale GHZ states show greater robustness against on-site potential defects,the fluctuation of couplings and losses of the system in comparison with the conventional adiabatic topological *** experimentally feasible qutrit-resonator coupling strengths and moderate decay rates of qutrits and resonators,fast topological pumping drastically improves the scalability of GHZ states with a high *** work opens up prospects for the realization of large-scale GHZ states based on fast topological pumping in the superconducting quantum circuit system,which provides potential applications of topological matters in quantum information processing.

关键词： topological pumping superconducting ciruit large-scale Greenberger-Horne-Zeilinger states

Mechanism of plasma ignition in electrothermal-chemical launcher

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Defence Technology（防务技术） 2016年第2期12卷 96-100页

作者： yong jin Yan-jie NI Hai-yuan LI Bao-ming LI National Key Laboratory of Transient Physics Nanjing University of Science and Technology

Plasma generator is a core component in an electrothermal-chemical(ETC) launcher. Its work state directly influences the launch efficiency of a system. The interaction between plasma and propellants is a very important mechanism in ETC technology. Based on the transient radiation model and open air plasma jet experiment, the mechanism of plasma ignition process is analyzed. Results show that the surface temperature of local solid propellant grain can quickly achieve the ignition temperature under the action of early transient plasma radiation. But it needs enough time to maintain the high energy flow to make self-sustained combustion of solid propellant grains. Because of the limited space characteristics of transient radiation, the near-field propellant grains can gain enough energy by the strong transient radiation to be ignited and achieve self-sustained combustion. The far-field propellant grains mainly gain the energy by the activated particles in plasma jet to be ignited and self-sustained combustion. Experiments show that plasma jet always has a high flow velocity in the area of the cartridge. Compared with conventional ignition, the solid propellant grains can obtain more quick and uniform ignition and self-sustained combustion by this kind of ablation controlled arc(ACA) plasma via energy skin effect of propellant grains, pre-heat temperature mechanism and high efficient jet diffusion.

关键词：等离子体点火发射装置电热化学机理等离子体射流固体推进剂等离子体发生器持续燃烧