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Spatio-temporal Evolution of Marine Fishery Industry Ecosystem Vulnerability in the Bohai Rim Region

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Chinese Geographical Science 2019年第6期29卷 1052-1064页

作者： LI Bo jin xiaoming Center for Studies of Marine Economy and Sustainable Development Liaoning Normal University

The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine *** vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to *** results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the *** to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, ***, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction.

关键词： marine fishery marine industry ecosystem vulnerability spatio-temporal evolution Bohai Rim Region

Cortical stimulation for treatment of neurological disorders of hyperexcitability: a role of homeostatic plasticity

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Neural Regeneration Research 2019年第1期14卷 34-38页

作者： Zhi Chai Cungen Ma xiaoming jin Basic Medical College Shanxi Key Laboratory of Innovative Drugs for Serious Illness Based on Inflammatory Reactions Neurobiology Research Center Shanxi University of Chinese Medicine Institute of Brain Science Shanxi Datong University Department of Anatomy and Cell Biology Department of Neurological Surgery Spinal Cord and Brain Injury Research Group Stark Neurosciences Research Institute Indiana University School of Medicine

Hyperexcitability of neural network is a key neurophysiological mechanism in several neurological disorders including epilepsy, neuropathic pain, and tinnitus. Although standard paradigm of pharmacological management of them is to suppress this hyperexcitability, such as having been exemplified by the use of certain antiepileptic drugs, their frequent refractoriness to drug treatment suggests likely different pathophysiological mechanism. Because the pathogenesis in these disorders exhibits a transition from an initial activity loss after injury or sensory deprivation to subsequent hyperexcitability and paroxysmal discharges, this process can be regarded as a process of functional compensation similar to homeostatic plasticity regulation, in which a set level of activity in neural network is maintained after injury-induced activity loss through enhanced network excitability. Enhancing brain activity, such as cortical stimulation that is found to be effective in relieving symptoms of these disorders, may reduce such hyperexcitability through homeostatic plasticity mechanism. Here we review current evidence of homeostatic plasticity in the mechanism of acquired epilepsy, neuropathic pain, and tinnitus and the effects and mechanism of cortical stimulation. Establishing a role of homeostatic plasticity in these disorders may provide a theoretical basis on their pathogenesis as well as guide the development and application of therapeutic approaches through electrically or pharmacologically stimulating brain activity for treating these disorders.

关键词： homeostatic plasticity epilepsy neuropathic pain cerebral cortex hyperexcitability brain injury tinnitus cortical stimulation

Improvement of Mechanical Properties of Wood-Plastic Composite Floors Based on the Optimum Structural Design

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Acta Mechanica Solida Sinica 2016年第4期29卷 444-454页

作者： Yang Zhang Ping Xue Yun Ding Mingyin Jia Jianchen Cai xiaoming jin College of Mechanical and Electrical Engineering Beijing University of Chemical Technology College of Mechanical Engineering Quzhou University

A study is carried out on the structural design of wood-plastic composite floors. The geometric parameters of the cavities, the structure, and the means to optimize the performance of these light boards are investigated. Various structural parameters of the boards, such as size, shape, and the pattern of cavities are also studied. The optimal structure can be determined by calculation and analysis of the strength, stiffness, weight and cost of the material. A finite element model for the mechanical analysis of wood-plastic composite floors is established; and the results are used to verify the strength criteria under bending deformation, which is the most common loading condition of flooring board.

关键词： wood plastic composite cavities flooring board optimal structure the finite element model

Kinetic model for hydroisomerization reaction of C_(8)-aromatics

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Frontiers of Chemical Science and Engineering 2008年第1期2卷 10-16页

作者： Ouguan XU Hongye SU xiaoming jin Jian CHU Zhijiang College Zhejiang University of TechnologyHangzhou 310024China National Key Laboratory of Industrial Control Technology Institute of Advanced Process ControlZhejiang UniversityHangzhou 310027China

Based on the reported reaction networks,a novel six-component hydroisomerization reaction net-work with a new lumped species including C_(8)-naphthenes and C_(8)-paraffins is proposed and a kinetic model for a commercial unit is also *** empirical catalyst deactivation function is incorporated into the model accounting for the loss in activity because of coke forma-tion on the catalyst surface during the long-term *** Runge-Kutta method is used to solve the ordinary differential equations of the *** reaction kinetic parameters are benchmarked with several sets of balanced plant data and estimated by the differential vari-able metric optimization method(BFGS).The kinetic model is validated by an industrial unit with sets of plant data under different operating conditions and simulation results show a good agreement between the model predic-tions and the plant observations.

关键词： C_(8)-aromatics hydroisomerization reaction network kinetic model catalyst deactivation function parameter estimation

One-step scalable preparation of N-doped nanoporous carbon as a high-performance electrocatalyst for the oxygen reduction reaction

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Nano Research 2013年第4期6卷 293-301页

作者： Zhenyu Liu Guoxin Zhang Zhiyi Lu Xiuyan jin Zheng Chang xiaoming Sun State Key Laboratory of Chemical Resource Engineering P. O. Box 98 Beijing University of Chemical Technology Beijing 100029 China

N-doped porous carbon materials have been prepared by a simple one-step pyrolysis of ethylenediaminetetraacetic acid （EDTA） and melamine in the presence of KOH and Co（NO3）2·6H20. The combination of the high specific area （1,485 m2.g-l）, high nitrogen content （10.8%） and suitable graphitic degree results in catalysts exhibiting high activity （with onset and half-wave potentials of 0.88 and 0.79 V vs the reversible hydrogen electrode （RHE）, respectively） and four-electron selectivity for the oxygen reduction reaction （ORR） in alkaline medium---comparable to a commercial Pt/C catalyst, but far exceeding Pt/C in stability and durability. Owing to their superb ORR performance, low cost and facile preparation, the catalysts have great potential applications in fuel cells, metal-air batteries, and ORR-related electrochemical industries.

关键词： oxygen reductionreaction nitrogen-doping porous carbon

Ecological stoichiometry and biomass response of Agropyron michnoi *** simulated N deposition in a sandy grassland,China

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Journal of Arid Land 2020年第5期12卷 741-751页

作者： jin xiaoming YANG Xiaogang ZHOU Zhen ZHANG Yingqi YU Liangbin ZHANG jinghua LIANG Runfang Department of Life Science Hulunbuir UniversityHulunbuir 021008China College of Environmental Science Northeast Normal UniversityChangchun 130024China Grassland Research Institute Chinese Academy of Agricultural SciencesHohhot 010010China

Sandy grassland in northern China is a fragile ecosystem with poor soil *** how plant species regulate growth and nutrient absorption under the background of nitrogen(N)deposition is crucial for the management of the sandy grassland *** carried out a field experiment with six N levels in the Hulunbuir Sandy Land of China from 2014 to 2016 and explored the Agropyron michnoi *** of both aboveground and belowground biomasses and carbon(C),N and phosphorus(P)concentrations in the plant tissues and *** increasing N addition,both aboveground and belowground biomasses and C,N and P concentrations in the plant tissues increased and exhibited a single-peak curve.C:N and C:P ratios of the plant tissues first decreased but then increased,while the trend for N:P ratio was *** peak values of aboveground biomass,belowground biomass and C concentration in the plant tissues occurred at the level of 20 g N/(m2•a),while those of N and P concentrations in the plant tissues occurred at the level of 15 g N/(m2•a).The maximum growth percentages of aboveground and belowground biomasses were 324.2%and 75.9%,respectively,and the root to shoot ratio(RSR)decreased with the addition of N.N and P concentrations in the plant tissues were ranked in the order of leaves>roots>stems,while C concentration was ranked as roots>leaves>*** increase in N concentration in the plant tissues was the largest(from 34%to 162%),followed by the increase in P(from 10%to 33%)and C(from 8%to 24%)*** aboveground biomass was positively and linearly correlated with leaf C,N and P,and soil C and N concentrations,while the belowground biomass was positively and linearly correlated with leaf N and soil C *** results showed that the accumulation of N and P in the leaves caused the increase in the aboveground biomass,while the accumulation of leaf N resulted in the increase in the belowground biomass.N deposition can alter the allocat

关键词： biomass nitrogen deposition plant tissue C,N and P stoichiometry sandy grassland

Impact of TID on response to pulsed X-ray irradiation in the bipolar operational amplifier

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Science China(Technological Sciences) 2015年第2期58卷 390-396页

作者： LI Rui Bin WANG Gui Zhen CHEN Wei MA Qiang LIU Yan LIN Dong Sheng YANG ShanChao BAI XiaoYan QI Chao jin xiaoming State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear Technology

Groups of a typical operational amplifier-μA741 were irradiated in a cobalt unit, each group accumulating a different total ionizing dose （TID）. The results showed that the TID caused power consumption current and slew rate （SR） to degenerate in ultra-linearity, owing to a severe reduction in the current gain of the internal LPNP transistors. Pulsed X-ray irradiation experiments were carried out on the μA741 groups with different values, and the results revealed that the impact on the response to the pulsed X-ray irradiation was greater when the devices absorbed more TID. The mechanism for this is explained on the basis of the circuit construction of the μA741; the sensitive parameters of the circuit were obtained via simulation on SP1CE. The simulation results additionally showed that if the sensitive parameters were optimized, the duration of interruption caused by the pulsed X-ray irradiation would be reduced significantly. In addition, several proposals are provided for hardening the devices.

关键词： TID pulsed X-ray irradiation operational amplifier simulation

Analysis of displacement damage effects on bipolar transistors irradiated by spallation neutrons

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Chinese Physics B 2019年第6期28卷 372-377页

作者： Yan Liu Wei Chen Chaohui He Chunlei Su Chenhui Wang xiaoming jin Junlin Li Yuanyuan Xue School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect(Northwest Institute of Nuclear Technology) Xi’an 710024China

Displacement damage induced by neutron irradiation in China Spallation Neutron Source(CSNS) is studied on bipolar transistors with lateral PNP, substrate PNP, and vertical NPN configurations, respectively. Comparison of the effects on different type transistors is conducted based on displacement damage factor, and the differences are analyzed through minority carrier lifetime calculation and structure analysis. The influence of CSNS neutrons irradiation on the lateral PNP transistors is analyzed by the gate-controlled method, including the oxide charge accumulation, surface recombine velocity,and minority carrier lifetime. The results indicate that the total ionizing dose in CSNS neutron radiation environment is negligible in this study. The displacement damage factors based on 1-MeV equivalent neutron flux of different transistors are consistent between Xi’an pulse reactor(XAPR) and CSNS.

关键词： displacement damage China Spallation Neutron Source(CSNS) reactor neutrons bipolar transistors

基于李雅普诺夫稳定性的自适应模糊控制器设计

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控制理论与应用 2000年第4期17卷 629-632页

作者：金晓明浙江大学工业控制技术国家重点实验室杭州310027

在动态系统模糊关系模型在线辨识的基础上 ,提出了一种用李雅普诺夫稳定性来进行自适应模糊控制器设计的新方法 .仿真研究和实验装置应用均表明 :该方法对于非线性、时滞过程的控制是有效的 ,具有实用价值 .

关键词：李雅普诺夫稳定性自适应模糊控制器设计