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Energy Scattering Theory for Electromagnetic NLS in Dimension Two

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Acta Mathematica Sinica,English Series 2018年第4期34卷 641-654页

作者： Jun yong ZHANG Ji qiang ZHENG Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China Beijing Computational Science Research Center Beijing 100193 P. R. China Department of Mathematics Universitd Nice Sophia-Antipolis 06108 Nice Cedex 02 France

We study the well-posedness and long-time behavior of solution to both defocusing and focusing nonlinear Schrodinger equations with scaling critical magnetic potentials in dimension two. In the defocusing case, and under the assumption that the initial data is radial, we prove interaction Morawetz-type inequalities and show the scattering holds in the energy space. The magnetic potential considered here is the Aharonov-Bohm potential which decays likely the Coulomb potential {x}-1.

关键词： Nonlinear Schrodinger equations Aharonov-Bohm potential global well-posedness scat-tering

Stem sap flow of Haloxylon ammodendron at different ages and its response to physical factors in the Minqin oasis-desert transition zone, China

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Journal of Arid Land 2023年第7期15卷 842-857页

作者： qiang Yuquan ZHANG Jinchun XU Xianying LIU Hujun duan Xiaofeng Minqin National Station for Desert Steppe Ecosystem Studies Minqin 733300China Gansu Desert Control Research Institute Lanzhou 730000China College of Forestry Gansu Agricultural UniversityLanzhou 730000China

Haloxylon ammodendron, with its tolerance of drought, high temperature, and salt alkali conditions, is one of the main sand-fixing plant species in the oasis-desert transition zone in China. This study used the TDP30(where TDP is the thermal dissipation probe) to measure hourly and daily variations in the stem sap flow velocity of H. ammodendron at three age-classes(10, 15, and 20 years old,which were denoted as H10, H15, and H20, respectively) in the Minqin oasis-desert transition zone,China, from May through October 2020. By simultaneously monitoring temperature, relative humidity,photosynthetically active radiation, wind speed, net radiation, rainfall, and soil moisture in this region, we comprehensively investigated the stem sap flow velocity of different-aged H. ammodendron plants(H10,H15, and H20) and revealed its response to physical factors. The results showed that, on sunny days, the hourly variation curves of the stem sap flow velocity of H. ammodendron plants at the three age-classes were mainly unimodal. In addition, the stem sap flow velocity of H. ammodendron plants decreased significantly from September to October, which also delayed its peak time of hourly variation. On rainy days, the stem sap flow velocity of H. ammodendron plants was multimodal and significantly lower than that on sunny *** daily water consumption of H. ammodendron plants at H10, H15, and H20 was 1.98, 2.82, and 1.91kg/d, respectively. Temperature was the key factor affecting the stem sap flow velocity of H. ammodendron at all age-classes. Net radiation was the critical factor influencing the stem sap flow velocity of *** at H10 and H15;however, for that at H20, it was vapor pressure deficit. The stem sap flow velocity of H. ammodendron was highly significantly correlated with soil moisture at the soil depths of 50and 100 cm, and the correlation was strengthened with increasing stand age. Altogether, our results revealed the dynamic changes of the stem sap flow

关键词： Haloxylon ammodendron stem sap flow stand age soil moisture water consumption Minqin oasis-desert transition zone

Lignin-based electrospun nanofiber membrane decorated with photo-Fenton Ag@MIF-100(Fe) heterojunctions for complex wastewater remediation

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Frontiers of Chemical Science and Engineering 2023年第7期17卷 930-941页

作者： Guodong Tian Chao duan Bingxu Zhou Chaochao Tian qiang Wang Jiachuan Chen State Key Laboratory of Biobased Material and Green Papermaking Qilu University of TechnologyShandong Academy of SciencesJinan 250353China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China

Membrane technology for wastewater remediation has aroused wide interest owing to its unique properties and potential ***,it remains challenging to explore green,efficient and robust membrane material and technique for complex wastewater ***,we proposed using a simple electrospinning and in situ seeding method to fabricate a lignin-based electrospun nanofiber membrane(LENM)decorated with photo-Fenton Ag@MIL-100(Fe)heterojunctions for efficient separation of oil/water emulsions and degradation of organic *** to the embedded lignin in LENM,an ultrahigh MIL-100(Fe)loading(53 wt%)with good wettability and high porosity was *** a result,the hybrid Ag@MIL-100(Fe)/LENM exhibited excellent oil/water emulsions separation efficiency(more than 97%)without a compromise of water ***,the hybrid membrane showed an excellent dye removal with degradation of 99%methylene blue within 30 min under illumination,which is attributed to a synergy of dye adsorption/enrichment and photo-Fenton catalytic degradation from Ag@MIL-100(Fe).Therefore,the lignin-based photo-Fenton hybrid membrane can lay the foundation for the preparation and application of green,sustainable and versatile membrane materials and technologies for efficient complex wastewater remediation.

关键词： lignin electrospinning heterojunctions photo-Fenton catalysis wastewater remediation

Request pattern change-based cache pollution attack detection and defense in edge computing

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Digital Communications and Networks 2023年第5期9卷 1212-1220页

作者： Junwei Wang Xianglin Wei Jianhua Fan qiang duan Jianwei Liu Yangang Wang The 63rd Research Institute National University of Defense TechnologyNanjing210007China

Through caching popular contents at the network edge,wireless edge caching can greatly reduce both the content request latency at mobile devices and the traffic burden at the core ***,popularity-based caching strategies are vulnerable to Cache Pollution Attacks(CPAs)due to the weak security protection at both edge nodes and mobile *** CPAs,through initiating a large number of requests for unpopular contents,malicious users can pollute the edge caching space and degrade the caching *** paper firstly integrates the dynamic nature of content request and mobile devices into the edge caching framework,and introduces an eavesdroppingbased CPA ***,an edge caching mechanism,which contains a Request Pattern Change-based Cache Pollution Detection(RPC2PD)algorithm and an Attack-aware Cache Defense(ACD)algorithm,is proposed to defend against *** results show that the proposed mechanism could effectively suppress the effects of CPAs on the caching performance and improve the cache hit ratio.

关键词： Mobile edge computing Cache pollution attack Flash crowd

Glass Recognition and Map Optimization Method for Mobile Robot Based on Boundary Guidance

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 135-146页

作者： yong Tao He Gao Yufang Wen Lian duan Jiangbo Lan School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China Large Aircraft Advanced Training Center Beihang UniversityBeijing 100191China

Current research on autonomous mobile robots focuses primarily on perceptual accuracy and autonomous *** commercial and domestic constructions,concrete,wood,and glass are typically *** and visual mapping or planning algorithms are highly accurate in mapping wood panels and concrete ***,indoor and outdoor glass curtain walls may fail to perceive these transparent *** this study,a novel indoor glass recognition and map optimization method based on boundary guidance is ***,the status of glass recognition techniques is analyzed ***,a glass image segmentation network based on boundary data guidance and the optimization of a planning map based on depth repair are ***,map optimization and path-planning tests are conducted and compared using different *** results confirm the favorable adaptability of the proposed method to indoor transparent plates and glass curtain *** the proposed method,the recognition accuracy of a public test set increases to 94.1%.After adding the planning map,incorrect coverage redundancies for two test scenes reduce by 59.84%and 55.7%.Herein,a glass recognition and map optimization method is proposed that offers sufficient capacity in perceiving indoor glass materials and recognizing indoor no-entry regions.

关键词： Autonomous mobile robot Multi-sensor fusion Glass recognition Map optimization

Excited states of holographic superconductors from massive gravity

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Communications in Theoretical Physics 2022年第11期74卷 159-169页

作者： Qian Xiang Li Zhao yong-qiang Wang Institute of Theoretical Physics Lanzhou UniversityLanzhouGansu 730000China Lanzhou Center for Theoretical Physics and Key Laboratory of Theoretical Physics of Gansu Province Lanzhou UniversityLanzhouGansu 730000China

In this paper,we generalize the study of the model of holographic superconductors in excited states to the framework of massive gravity at the probe *** taking into account the effect of a massive graviton,we numerically present a family of solutions for holographic superconductors in excited states and find that the critical temperatures can be higher due to the effect of the massive graviton,in comparison with the superconductor in Einstein *** also investigate the condensates and conductivities in the ground state and the excited states by studying various parameters that determine the framework of gravity background.

关键词： AdS/CFT massive gravity holographic superconductors

The Fulde-Ferrell-Larkin-Ovchinnikov states in s and d-wave superconductor with spin-dependent bandwidth imbalance on square lattice

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Science China(Physics,Mechanics & Astronomy) 2016年第1期59卷 92-97页

作者： yong-Hui Wang Qing-qiang Meng Yan Chen Department of Physics and State Key Laboratory of Surface Physics Fudan UniversityShanghai 200433China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

We study numerically the phase diagram for s and d-wave fermionic superftuidity/superconductivity with spin-dependent band- width imbalance on a two-dimensional square-lattice. We also investigate the spontaneous space symmetry breaking states at low temperatures by solving the Bogoliubov-de Gennes equations. It is found that, the spatial configuration of the order parameter, both the uni-directional Fulde-Ferrell-Larkin-Ovchinnikov （FFLO） states and the two-dimensional FFLO state may show up in the presence of finite spin-dependent bandwidth imbalance. Moreover, we calculate the spectra of local density of states, and the experimental proposals of observing such FFLO states are therefore suggested.

关键词： FFLO state superconductivity superfluidity

Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： Jian-hua SHAO qiang GU yong-kang SHEN College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

Live microbial cells adsorb Mg2＋ more effectively than lifeless organic matter

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Frontiers of Earth Science 2018年第1期12卷 160-169页

作者： Xuan QIU Yanchen YAO Hongmei WANG yong duan State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Wuhan 430074 China School of Environmental Studies China University of Geosciences Wuhan 430074 China

The Mg2＋ content is essential in determining different Mg-CaCO3 minerals. It has been demonstrated that both microbes and the organic matter secreted by microbes are capable of allocating Mg2＋ and Ca2＋ during the formation of Mg-CaCO3, yet detailed scenarios remain unclear. To investigate the mechanism that microbes and microbial organic matter potentially use to mediate the allocation of Mg2＋ and Ca2＋ in inoculating systems, microbial mats and four marine bacterial strains （Synecho- coccus elongatus, Staphylococcus sp., Bacillus sp., and Desulfovibrio vulgaris） were incubated in artificial sea- water media with Mg/Ca ratios ranging from 0.5 to 10.0. At the end of the incubation, the morphology of the microbial mats and the elements adsorbed on them were analyzed using scanning electronic microscopy （SEM） and energy diffraction spectra （EDS）, respectively. The content of Mg2＋ and Ca2＋ adsorbed by the extracellular polysaccharide substances （EPS） and cells of the bacterial strains were analyzed with atomic adsorption spectroscopy （AAS）. The functional groups on the surface of the cells and EPS of S. elongatus were estimated using automatic potentiometric titration combined with a chemical equilibrium model. The results show that live microbial mats generally adsorb larger amounts of Mg2＋ than Ca2＋, while this rarely is the case for autoclaved microbial mats. A similar phenomenon was also observed for the bacterial strains. The living cells adsorb more Mg2＋ than Ca2＋, yet a reversed trend was observed for EPS. The functional group analysis indicates that the cell surface of S. elongatus contains more basic functional groups （87.24%）, while the EPS has more acidic and neutral functional groups （83.08%）. These features may be responsible for the different adsorption behavior of Mg2＋ and Ca2＋ by microbial cells and EPS. Our work confirms the differ-ential Mg2＋ and Ca2＋ mediation by microbial cells and EPS, which may provide insight into the processes that microbes use to

关键词： microbe adsorption magnesium calcium