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Journal of Systems Science & Complexity 2023年第3期36卷 1070-1088页

作者： CHEN Menghua wang Yunming wang xinping School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian 116028China

This paper is concerned with the problem of input-output finite-time guaranteed cost control for a kind of time-varying systems(TVSs).To reduce the transmission burden,an aperiodic-sampling-based event-triggered mechanism is proposed with an adaptive *** a time-varying Lyapunov functional involving some time-dependent piecewise matrices is ***-output finite-time stability(IO-FTS)conditions are presented for the closed-loop *** resorting to properties of the matrix polynomial,input-output finite-time stabilization criterions are further derived by recursive linear matrix *** the sampled-data static output feedback controller can be *** addition,the corresponding optimization problem about minimum values of both the guaranteed cost bound and system output norm are ***,a spring-mass-damper system illustrates the effectiveness and superiority.

关键词： Aperiodic-sampling-based adaptive event-triggered mechanism guaranteed cost control input-output finite-time stability time-varying system

Isolable Radical Ions of Main-Group Elements： Structures, Bonding and Properties

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Chinese Journal of Chemistry 2018年第7期36卷 573-586页

作者： Gengwen Tan xinping wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing Jiangsu 210023 China

Synthesis of stable main-group element-based radicals represents one of the most interesting topics in contemporary organometallic chem- istry, because of their vital roles in organic, inorganic and biological chemistry as well as materials science. However, the access of stable main-group element-based radicals is highly challenging owing to the lack of energetically accessible orbitals in the main-group elements. During the last decades, several synthetic strategies have been developed in obtaining these reactive species. Among them, utilizing the stericaliy demanding substituents and x-conjugated ligands has proven to be an effective approach. Weakly coordinating ions （WCAs） have also been found to be exceptionally practical in synthesizing radical cations of main-group elements. By introducing these stabilization methods, we have successfully prepared a variety of radical ions of p-block elements in the crystalline forms, and investigated their properties by different experimental and quantum chemical calculation methods. According to the investigations, magnetic stability was observed, resulting from the intramolecular electron-exchange interaction. Furthermore, we also found that the singlet-triptet energy gaps of the bis（triarylamine） diradical dications can be tunable by varying the temperature. These investigations open new avenues of the main-group element-based radicals for a large variety of applications.

关键词： oxidation reduction radicals main-group element weakly coordinating anions

Effects of shrub species and microhabitats on dew formation in a revegetation-stabilized desert ecosystem in Shapotou, northern China

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Journal of Arid Land 2014年第4期6卷 389-399页

作者： YanXia PAN xinping wang Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Dew is an important supplement water source in arid and semi-arid areas. In order to determine the dew formation on different kinds of soils associated with various shrub species and microhabitats, we performed measurement of accumulated dew formation amount and duration in October 2009 in a revegetation-stabilized arid desert ecosystem in Shapotou area, northern China. The results indicated that the accumulated dew formation amount was four times larger at open spaces as compared to under the canopy, and it was nearly twice as much under living Artemisia ordosica plants（L.A.） as compared to under living Caragana korshinskii plants（L.C.）. The opposite characteristics were found for dew duration between different microhabitats. Dew amounts at different vertical heights around the shrub stands were in the order of 50 cm above the canopy〉the canopy edge〉under the canopy. Dew amount continued to increase after dawn, and the proportion of average accumulated dew amount after dawn accounting for the average maximum amount increased from above the canopy to under the canopy. Dew formation duration after sunrise accounted for more than 50% of the total formation duration during the day time. Contrary to the distribution characteristics of dew amount, dew duration after dawn and total dew formation duration during the day time were both highest under the canopy, followed by at the canopy edge and then at 50 cm above the canopy. The portion of dew duration after dawn accounting for the total dew duration during the day time increased from above the canopy to under the canopy. From these results, we may conclude that dew availability as a supplemental water resource for improving the microhabitats in water-limited arid ecosystems is position dependent especially for the plant microhabitats at different stands layers.

关键词： dew amount dew duration shrub species microhabitat soil surface type

Selective catalytic reduction of NO by C_2H_2 over Ce-Al_2O_3 catalyst with rate-determining step of NO oxidation

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Journal of Natural Gas Chemistry 2012年第3期21卷 332-338页

作者： Suhua Yan xinping wang Wenchen wang Zequn Liu Jiahao Niu State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024LiaoningChina

Ce-A12O3 catalysts prepared by co-precipitation are investigated both in NO oxidation by 02 and in selective catalytic reduction of NO by C2H2 （C2H2-SCR）. It is found that C2H2-SCR is initiated and controlled by NO oxidation to NO2 over A12O3. Ce loading on A12O3 is almost inactive for NO oxidation below 350℃, since NO2 strongly adsorbs on cerium oxide, leading to the active sites being blocked, which was characterized by temperature-programmed desorption of NO and NO2 and Fourier transform infrared spectroscopy after NO＋O2 coadsorption over the samples. However, in the case of C2H2-SCR, Ce loading on A1203 significantly improves the reaction by accelerating the NO oxidation step in the temperature range of 250-450℃, since the nitrate species produced by NO2 adsorption is an active intermediate required by C2H2-SCR.

关键词： NOx removal NO oxidation nitrate species Ce-A1203 acetylene

Ecological adaptation strategies of annual plants in artificial vegetation-stabilized sand dune in Shapotou Region

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Science China Earth Sciences 2004年第z1期47卷 50-60页

作者： ZHANG Jingguang LI Xinrong wang xinping wang Gang Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou Experimental Research Station as example, study has been done on the adaptation strategies of annual plants to random environment through fixed quadrat observations of population changes and fixed plant determinations of individual growth, seed germination,population dynamics, spatial distribution pattern of population, competition and regulation. During the growing season, the survival rate of annual plants depends on the precipitation intensity and precipitation duration which activate the germination of seeds. The optimal germination strategy of annual plants in this habitat during the growing season appears as continuous germination under suitable conditions. Such continuous germination is an adaptive characteristic of annual plants to random environment. In addition, the variation processes of population size and regulation mechanism of E. poaeoides are studied. Statistical results of natural population in four consecutive years show that water condition in the habitat is the leading factor affecting the population dynamics of E. poaeoides. During the establishment period E. poaeoides had a higher death rate, but in the middle to later period they could survive stably. Due to the limitation of soil moisture, the competition among individuals for water inevitably led to self-thinning phenomena. Under very arid condition, the survival curve of annual herbs entirely appears as Deevey Ⅲ type (C type), but under relatively adequate precipitation condition, the survival curve appears as intermediate type. The strategy of life history obviously appears as r-strategy. Plant species of r-strategy often occurs in the early succession stage of the communities. In the relatively adequate and evenly-distributed rainfall years, E. poaeoides population exhibited a density-dependent, i. e., survival rate increased with decrease in population density. The main pattern to re

关键词： Shapotou region Eragrostis poaeoides ecological adaptation strategy.

Effect of dispersion and distribution of tungsten on W/HZSM-5 for selective catalytic reduction of NO by acetylene

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Journal of Natural Gas Chemistry 2008年第4期17卷 332-336页

作者： Ran Bi xinping wang Zhiguang Liu Jing Chen State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 Liaoning China

Catalytic performance of W/HZSM-5 in selective catalytic reduction of NO by acetylene was investigated in a reaction system with 1600 ppm of NO, 800 ppm of C2H2, and 9.95% of O2 in He. It was found that promotional effect of tungsten on the reaction is strongly affected by catalyst preparation conditions and Si/Al ratio of the parent zeolite. A better dispersion of tungsten on HZSM-5 and relatively more monomeric tungsten species were found on 8%W/HZSM-5 prepared by impregnation of the zeolite with lower SiO2/A1203 ratio （25） in ammonic ammonium tungstate solution and calcination of the resulting material at higher temperature （550 ℃）. The highest NO conversion to N2 of 86.3% in the reaction system was obtained at 350 ℃ over the catalyst thus prepared. The mechanism of monomeric tungsten species improving the C2H2-SCR can be attributed to accelerating the formation of active nitrate species.

关键词： nitric oxide selective catalytic reduction tungsten HZSM-5

Air-stable diradical dications with ferromagnetic interaction exceeding the thermal energy at room temperature: from a monomer to a dimer

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Science China Chemistry 2018年第3期61卷 300-305页

作者： Wenqing wang Lei wang Sheng Chen Wenbang Yang Zaichao Zhang xinping wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Collaborative Innovation Center of Advanced Microstructures Nanjing University School of Chemistry and Chemical Engineering Huaiyin Normal University

Two tetraazacyclophane dications(1^(2+) and 2^(2+)) with different remote substituents have been synthesized, isolated and *** electronic structures and physical property were studied by various spectroscopic techniques, single crystal X-ray diffraction,super conducting quantum interference device(SQUID) measurements and theoretical calculations. The dications have triplet ground states with ferromagnetic interaction exceeding the thermal energy at room temperature. The solid-state structures of these species were tunable by substituent effect, with 1^(2+) as a monomer and 2^(2+) as a dimer.

关键词： diradical dication triplet ground state ferromagnetic interaction X-ray crystal structure

Cascade failure modeling and resilience analysis of mine cyber physical systems under deliberate attacks

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Journal of Safety Science and Resilience 2024年第3期5卷 266-280页

作者： xinping wang Jialin Zhu Chang Su Xinyue Zhen School of Management Xi'an University of Science and Technology Xi'an710054China School of Safety Science and Engineering Xan University of Science and TechnologyXi'an0054China

Guided by the intelligent construction of coal mines and integrating the concept of the Cyber-Physical System(CPS),a novel approach to a coal mine information-physical fusion system is *** concept emerges from the advancement of intelligent mines and the growing need for enhanced safety in coal mine *** a system safety perspective,this approach aims to effectively evaluate security issues by better integrating the informational and physical layers of intelligent ***,research in areas such as power grids and water networks has widely adopted concepts of cascade failures and *** is suggested that the CPS framework be adapted to the mining *** the critical role of coal mines in China's energy security and their vulnerability to cyber attacks,a mine-specific CPS system is *** system incorporates a model of mine information-physical fusion,including networks for mine operations,management,and control,tailored to the unique conditions of mine shafts and underground *** Markov process theory,the paper delves into the theoretical study of the cascade failure process under deliberate attack *** analysis is essential to effectively assess the safety issues within the information-physical system,providing vital support for fault prediction and safety *** model of cascading failures in the mine information-physical system is developed,and based on an analysis of resilience and robustness,the study identifies key factors influencing the security of mine information-physical *** factors affecting the reliability of these systems include the number of system nodes,node coupling,edge count,and the interconnection methods of the dual-layer dependency *** paper concludes by discussing the challenges in analyzing the security of information-physical systems and suggesting directions for future research.

关键词： Minecyber physical system Cascading failure Resilience Robustness

Cyclic(Amino)(Aryl)Nitrenium Cations with Lewis Acidity Controlled by Remote Substituents

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Chinese Journal of Chemistry 2022年第3期40卷 311-316页

作者： Wenqing wang Xin Zheng Leran Zhang Shunjie Li Yue Zhao xinping wang College of Chemistry and Material Science Key Laboratory of Functional Molecular SolidsMinistry of EducationAnhui Laboratory of Molecule-Based MaterialsAnhui Normal UniversityWuhuAnhui 241002China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China College of Science Henan Agricultural UniversityZhengzhouHenan 450002China

N-Heterocyclic nitrogen Lewis acids are important in synthetic *** cyclic(amino)(aryl)nitrenium cations,cyc-1^(+)-cyc-3^(+),were synthesized by chemical oxidation of aryl azo compounds with different substituents,H and I,at the para positions of the phenyl *** excited triplet states of cyc-1^(+)-cyc-3^(+) abstract H-atoms step by step to generate radical intermediates cyc-1H^(*+-)cyc-3H^(*+)traced by EPR spectroscopy and products cyc-1H^(2+)-cyc-3H^(2+) characterized by single crystal X-ray *** Lewis acidity of species cyc-1^(+)-cyc-3^(+) are remote ***-2^(+)-cyc-3^(+) have much higher acidity than those previously reported congeners based on energies of *** electrophilicity enables them to form Lewis adducts with neutral Lewis base Me_(3)P,and to gain one-electron to produce neutral radicals cyc-1^(*)-cyc-3^(*).

关键词： Nitrenium cation Acidity Radicals Excited triplet state Electrophilicity

Review of the ecohydrological processes and feedback mechanisms controlling sand-binding vegetation systems in sandy desert regions of China

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Chinese Science Bulletin 2013年第13期58卷 1483-1496页

作者： LI XinRong ZHANG ZhiShan HUANG Lei wang xinping Shapotou Desert Research and Experimental Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions of Gansu Province

Soil water is the key abiotic limiting factor in desert areas and hydrological processes determine the vegetation composition, patterns and processes in desert regions. The hydrological processes can be altered by vegetation succession. In this paper, we review the major advances in ecohydrological research and their potential impact on plant-water relations in revegetated desert communities. The major advances in ecohydrological research over the past 50 years in desert areas were analyzed using a case study that investigated the long-term ecosystem effects of sand-binding vegetation in the Tengger Desert. Key challenges and opportunities for ecohydrology research in the future are also discussed in the context of the major scientific issues affecting sand binding vegetation.

关键词：生态水文过程沙漠地区植被系统固沙机制反馈中国控制