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近岸海域多环芳烃生态系统动力学模型及生境影响

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中国环境科学 2016年第5期36卷 1540-1546页

作者：张晓霞程嘉熠陶平邵秘华朱京海大连海事大学环境科学与工程学院辽宁大连116000 辽宁省环境保护厅辽宁沈阳110000

利用生态动力学模型Delf3D,对大连葫芦山湾海域多环芳烃(PAHs)在海洋中的理化及生态动力学过程进行耦合,并以大连葫芦山湾实际监测数据及相关文献资料为基础,确定了一套适用于该近岸海域PAHs生态动力学过程的特征参数,模拟研究了PAHs在... 详细信息

利用生态动力学模型Delf3D,对大连葫芦山湾海域多环芳烃(PAHs)在海洋中的理化及生态动力学过程进行耦合,并以大连葫芦山湾实际监测数据及相关文献资料为基础,确定了一套适用于该近岸海域PAHs生态动力学过程的特征参数,模拟研究了PAHs在近岸海域生态动力学过程.以浮游植物生长率作为指示近岸海域生态系统健康程度的指标,将PAHs含量的数值模拟结果与浮游植物生长率的动力学响应方程相拟合,定量的评估了PAHs对海洋生态系统的影响.结果显示:排污口选址于水深大、流速快、水动力强处,对PAHs污染物扩散、水质改善具有显著作用,反之造成PAHs大规模富集.PAHs富集作用对该湾生境影响较显著,湾顶水动力作用微弱,浮游生物生长率削减度高达18%.Arc GIS分析显示,浮游生物生长率削减程度与PAHs时空分布并不完全一致,体现海湾生态系统的动力复杂性与结构稳固性.

关键词：近岸海域生态动力学模型多环芳烃数值模拟 Delft3D

The varieties of Heisenberg vertex operator algebras

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Science China Mathematics 2017年第3期60卷 379-400页

作者： CHU Yan Jun LIN Zong zhu School of Mathematics and Statistics Henan University Department of Mathematics Kansas State University

For a vertex operator algebra V with conformal vector w, we consider a class of vertex operator subalgebras and their conformal vectors. They are called semi-conformal vertex operator subalgebras and semi- conformal vectors of （V, w）, respectively, and were used to study duality theory of vertex operator algebras via coset constructions. Using these objects attached to （V,w）, we shall understand the structure of the vertex operator algebra （V,w）. At first, we define the set Sc（V,w） of semi-conformal vectors of V, then we prove that Sc（V,w） is an aiYine algebraic variety with a partial ordering and an involution map. Corresponding to each semi-conformal vector, there is a unique maximal semi-conformal vertex operator subalgebra containing it. The properties of these subalgebras are invariants of vertex operator algebras. As an example, we describe the corresponding varieties of semi-conformal vectors for Heisenberg vertex operator algebras. As an application, we give two characterizations of Heisenberg vertex operator algebras using the properties of these varieties.

关键词： vertex operator algebra semi-conformal vector variety

Performance for Device-to-Device Communication with Three-Time-Slot Two-Way Amplify-and-Forward Relay Protocol

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China Communications 2015年第11期12卷 24-34页

作者： CAI Yan NI Yiyang zhu Hongbo College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsKey Laboratory of Wireless Communications of Jiangsu Province

Multi-hop device-to-device(D2D) communication can significantly improve the system performance. This paper studied the outage performance of D2 D communication assisted by another D2 D user using three-timeslot two-way amplify-and-forward relaying protocol over Rayleigh fading channels. Considering the co-channel interference from cellular user at the D2 D node,the approximate expression for the overall outage probability was derived. Furthermore,a power allocation optimum method to minimize the outage probability was developed,and the closed form expression for the optimal power allocation coefficient at the relay was derived. Simulation results demonstrate accuracy of the derived outage probability expressions. Simulation results also demonstrate that the outage performance can be improved using the proposed optimal power allocation method.

关键词： D2D communication outage probability power allocation amplify-and-forward relaying protocol

Gender Differences and Identities in Chinese Advertising Language

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海外英语 2019年第3期 227-229页

作者：朱荣萍河南工业职业技术学院应用外语系

It is assumed that men and women differ to some extent in using language in various social domains. Apart from distinctive physiological features, as a vehemently convincing symbol, the language one uses may mark his gender with special *** on the selection of thirty-two Chinese commercial ads from TV, the paper, from the perspective of sociolinguistics, especially the pertinence between language and gender, attempts to explore how gender identities are manifested and constructed throughqualitative analyses of advertising language. Then, the paper also tries to present some potential accounts for the different genderidentities and some suggestions for reducing sexism through advertising language.

关键词： advertisements gender differences identities

Surface modifications of Pt-based atomically ordered nanoparticles to improve catalytic performances for oxygen reduction reaction

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Progress in Natural Science:Materials International 2020年第6期30卷 890-895页

作者： Libo Zhang Xiaoran Wang Hong zhu State Key Laboratory of Chemical Resource Engineering Institute of Modern Catalysis Department of Organic Chemistry Beijing Engineering Centre for Hierarchical Catalysts School of Science Beijing University of Chemical Technology

Bimetallic platinum-cobalt(Pt–Co) nanostructure catalysts represent superior catalytic performances for oxygen reduction reaction(ORR). In a variety of Pt–Co catalyst structures, atomically ordered structure catalysts show excellent catalytic performances in the ORR. In this work, for promoting their catalytic performances, atomically ordered Pt Co nanoparticles(Pt Co/C) with carbon supported were successfully prepared by an improved impregnation method and annealing. Then, the ordered Pt Co/C catalysts have been significantly improved by doped with ultralow amount of Au and Cr transition metal. The physical and electrochemical test results demonstrate the Cr–Pt Co/C and Au–Pt Co/C catalysts have superior catalytic performances including mass activity and stability compared to commercialized Johnson Matthey(JM) Pt/C, which was the result of the modified electronic properties of Pt surface and atomically ordered structure. The presence of Au and Cr enhances the stability of Pt Co/C catalysts. This work represents a simple way to promote the catalytic performances of the atomically ordered catalysts.

关键词： Low-pt Proton exchange membrane fuel cells Atomically ordered structure Oxygen reduction reaction Surface modification

On an Entropy of Zk＋-Actions

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Acta Mathematica Sinica,English Series 2014年第3期30卷 467-480页

作者： Yu Jun zhu Wen Da ZHANG College of Mathematics and Information Science and Hebei Key Laboratory of Computational Mathematics and ApplicationsHebei Normal University College of Mathematics and Information Science Hebei Normal University

In this paper,a definition of entropy for Z＋k（k≥2）-actions due to Friedland is *** the traditional definition,it may take a nonzero value for actions whose generators have finite（even zero） entropy as single *** basic properties are investigated and its value for the Z＋k-actions on circles generated by expanding endomorphisms is ***,an upper bound of this entropy for the Z＋k-actions on tori generated by expanding endomorphisms is obtained via the preimage entropies,which are entropy-like invariants depending on the ＂inverse orbits＂ structure of the system.

关键词： Entropy preimage entropy Zk+-action

Unified properties of a weakly interacting Fermi gas in a weak magnetic field

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Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1072-1078页

作者： MEN FuDian LIU Hui zhu HouYu College of Physical Science and Technology China University of Petroleum(East China)Dongying 257061China

When the orbital motion and the spin motion of particles were considered simultaneously,the thermodynamic potential function of a weakly interacting Fermi gas in a weak magnetic field was derived using the thermodynamics method. Based on the derived expression,the analytical expressions of energy,heat capacity,chemical potential,susceptibility and stability conditions of the system were given,and the effects of the interparticle interactions as well as the magnetic field on the properties of the system were analyzed. It was shown that the magnetic field always causes energy and stability to decrease,while the chemical potential of the system to increase. The repulsive(attractive) interactions always increase(decrease) energy and stability,but decrease(increase) the chemical potential and paramagnetism. The repulsive(attractive) interactions decrease(increase) heat capacity of the system at high temperatures but increase(decrease) it at low temperatures.

关键词： Fermi gas magnetic field interaction statistical property

Research progress of low-dimensional perovskites:synthesis,properties and optoelectronic applications

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Journal of Semiconductors 2017年第1期38卷 19-27页

作者： Xinzhe Min Pengchen zhu Shuai Gu Jia zhu National Laboratory of Solid State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The lead halide-based perovskites,for instance,CH3NH3PbX3 and CsPbX3（X = Cl,Br,I）,have received a lot of *** with bulk materials,low-dimensional perovskites have demonstrated a range of unique optical,electrical and mechanical properties,which enable wide applications in solar cells,lasers and other optoelectronic *** this paper,we provide a summary of the research progress of the low-dimensional perovskites in recent years,from synthesis methods,basic properties to their optoelectronic applications.

关键词： low-dimensional perovskites nanoplates nanowires quantum dots solar cells semiconductor lasers

Shaking Table Model Test of Isolated Structure on Soft Site and Analysis on Its Isolation Efficiency

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第2期34卷 169-176页

作者： Yu Xu zhuang Haiyang zhu Chao Department of Civil Engineering Nanjing Institute of Technology Institute of Geotechnical Engineering Nanjing University of Technology

Adopting a soft site model built on soft interlayer soil foundation,a shaking table test for soft interlayer soil-isolated structure interaction is conducted to investigate the seismic response of isolated structure on soft site,and analyze its isolation *** results show that the test can reflect the earthquake response characteristics of isolated structure on soft *** is on soft site that the dynamic characteristics of isolated structure,acceleration magnification factor(AMF)of isolated structure and isolation efficiency of the isolation layer differ from those on rigid foundation with an soil-structure interaction(SSI)effect,represented by the reduction in fundamental vibration frequency of isolated structure and the increase of damping ratio with changes of the SSI *** can either increase or decrease AMF of isolated structure on soft site,depending on the characteristics of earthquake motion ***,the isolation efficiency of isolation layer on soft site is decreased with the SSI effect,which is related to the peak ground acceleration(PGA)and the characteristics of earthquake motion input.

关键词： isolated structure shaking table model test soil-structure interaction(SSI) seismic response isolation efficiency