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Toxicity of Fluoranthene and Its Biodegradation by Cyclotella caspia Alga

Journal of Integrative Plant Biology 2006年第2期48卷 169-180页

作者： yu Liu Tian-Gang Luan ning-ning Lu Chong-yu Lan School of Life Sciences State Key Laboratory for Biocontrol Sun Yet-sen （Zhongshan） University Guangzhou 510275 China School of Environmental Sciences and Engineering Sun Yet-sen （Zhongshan） University Guangzhou 510275 China

Fluoranthene Is one of the polynuclear aromatic hydrocarbons with four benzene rings. Because of Its toxicity, mutagenlclty, and carclnogenlclty, fluoranthene Is on the black lists of 129 and 68 priority pollutants established by US Environmental Protection Agency and the People＇s Republic of China, respectively. In recent years, the amount of fluoranthene In the aquatic environment has been Increasing with Increases In anthropogenlc discharge. Based on the biological investigation of tidal water In the Futlan mangrove, Cycioteila ~aspla was selected as the dominant algal species to determine the toxicity of fluoranthene towards C. caspla alga and to Investigate the blodegradatlon of fluoranthene by C. caspla under pure culture. The toxicity experiment showed that the 96-h EC50 value for fluoranthene was 0.2 mg/mL. Four parameters, namely C. caspla algal growth rate, chlorophyll （Chl） a content, cell morphology, and superoxlde dlsmutase （SOD） activity, were chosen as Indices of toxicity and were measured at 6 d （144 h）. The results showed that：（Ⅰ） the toxicity of fluoranthene towards C. caspla alga was obvious; （Ⅱ） C. caspla algal growth rate and Chl a content decreased with Increasing concentrations of fluoranthene; and （Ⅲ） the rate of cell deformation and SOD activity Increased with Increasing concentrations of fluoranthene. The blodegradatlon experiment showed that：（Ⅰ） the rate of physical degradation of fluoranthene was only 5.86%; （Ⅱ） the rate of blodegradatlon of fluoranthene on the 1st and 6th days （l.e. at 24 and 144 h） was approximately 35% and 85%, respectively; and （Ⅲ） the blodegradatlon capability of C. caspla alga towards fluoranthene was high. It is suggested that further Investigations on the toxicity of fluoranthene towards algae, as well as on algal blodegradatlon mechanisms, are of great Importance to use C. caspla as a biological treatment species In an organic wastewater treatment system.

关键词： biodegradation Cyclotella caspia fluoranthene toxicity.

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Signatures of shear thinning-thickening transition in steady shear flows of dense non-Brownian yield stress systems

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Science China Chemistry 2015年第6期58卷 1013-1020页

作者： Wen Zheng yu Shi ning Xu CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Department of Physics University of Science and Technology of China

Steady shear flows of dense athermal systems composed of soft disks are investigated via non-equilibrium molecular dynamics simulations, from which we sort out links among the structure, dynamics, and shear rheology. The systems at rest are jammed packings of frictionless disks with a nonzero yield stress. Driven by low shear rates, the flows shear thin due to the presence of the nonzero yield stress, but transit to shear thickening above a crossover shear rate γc - At γc, we observe the strongest struc- tural anisotropy in the pair distribution function, which serves as the structural signature of the shear thinning-thickening tran- sition. We also observe dynamical signatures associated with the transition： At γc , scaling behaviors of both the mean squared displacement and relaxation time undergo apparent changes. By performing a simple energy analysis, we reveal an underlying condition for the shear thickening to occur： d（lnTg）/d（Inγ）〉 2 with Tg the kinetic temperature. This condition is confirmed by simulations.

关键词： shear thickening shear thinning structural anisotropy dynamics kinetic temperature

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A secure routing scheme based on social network analysis in wireless mesh networks

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Science China Earth Sciences 2016年第12期59卷 139-150页

作者： Yao yu Zhaolong ning Lei GUO College of Information Science and Engineering Northeastern UniversityShenyang 110819China School of Software Dalian University of TechnologyDalian 116620China State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210093China

As an extension of wireless ad hoc and sensor networks, wireless mesh networks(WMNs) are employed as an emerging key solution for wireless broadband connectivity improvement. Due to the lack of physical security guarantees, WMNs are susceptible to various kinds of attack. In this paper, we focus on node social selfish attack, which decreases network performance significantly. Since this type of attack is not obvious to detect, we propose a security routing scheme based on social network and reputation evaluation to solve this attack issue. First, we present a dynamic reputation model to evaluate a node's routing behavior, from which we can identify selfish attacks and selfish nodes. Furthermore, a social characteristic evaluation model is studied to evaluate the social relationship among nodes. Groups are built based on the similarity of node social status and we can get a secure routing based on these social groups of nodes. In addition, in our scheme, nodes are encouraged to enter into multiple groups and friend nodes are recommended to join into groups to reduce the possibility of isolated nodes. Simulation results demonstrate that our scheme is able to reflect node security status, and routings are chosen and adjusted according to security status timely and accurately so that the safety and reliability of routing are improved.

关键词： wireless mesh networks node selfish social network analysis secure routing Markov chain

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New Geometry with All Killing Vectors Spanning the Poincaré Algebra

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Chinese Physics Letters 2012年第4期29卷 15-18页

作者： huang Chao-Guang TIAN yu WU Xiao-ning XU Zhan ZHOU Bin Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049 Theoretical Physics Center for Science Facilities Chinese Academy of SciencesBeijing 100049 Graduate University of Chinese Academy of Sciences Beijing 100049 Institute of Mathematics Academy of Mathematics and System ScienceChinese Academy of SciencesBeijing 100190 Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of SciencesBeijing 100190 Department of Physics Tsinghua UniversityBeijing 100084 Department of Physics Beijing Normal UniversityBeijing 100875

The new four-dimensional geometry whose Killing vectors span the Poincaré algebra is presented and its structure is *** new geometry can be regarded as the Poincaré-invariant solution of the degenerate extension of the vacuum Einstein field equations with a negative cosmological constant and provides a static cosmological spacetime with a Lobachevsky *** motion of free particles in the spacetime is discussed.

关键词： Poincaré space Killing

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Coercive Force and Antimagnetizing Mechanism Relating to Size of Ferromagnetic Microcrystal--A Consummating to Result of Stoner-Wohlforth Theory

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Journal of Rare Earths 2004年第z1期22卷 79-83页

作者： yu ning Ji Jingwen College of Sciences Northeastern University Shenyang 110004 China College of SciencesNortheastern University Shenyang 110004 China

The expression of critical size of ferromagnetic microcrystal in an external magnetic field with an intensity of H is derived by means of comparing energies of domain structure *** ferromagnetic microcrystal here means an ferromagnetic single crystal with the size which is smaller than L0, and L0 is the critical value of the size of single-domain particles at the external magnetic field intensity H =***, the coercive strength H(Ls) relating to the size of microcrystal Ls is given and quantitatively evaluated with the material SmCo5 as an *** is thus concluded that if L0 ＞ Ls ＞ LC, the antimagnetization of microcrystal will be subjected to a multi-domain process just like the particles of a size greater than L0, only if Ls ＜ LC, the anti-magnetizaton will be carried on in accordance with the Stoner-Wohlforth mechanism( LC is the maximum size of microcrystal with MHcth ).It is suggested that the material RECo5 is available to make an advanced magnet with MHC = 2 K/Mc.

关键词： magnetization mechanism coercive force ferromagnetic microcrystal

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Optimal Technology Investment under Emission Trading Policy

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Journal of Systems Science and Systems Engineering 2020年第2期29卷 143-162页

作者： Shuo huang Zhong Wen Jian Chen ning Cui School of Economics and Management Tsinghua UniversityBeijing 100084China Beijing Foreign Studies University China Southern Asset Management Co. Ltd.

Low-carbon economy is gaining growing attention nowadays as global warming *** a market-based policy,emission trading policy is widely considered an effective means to achieve the doublewin of economic development and environmental *** such circumstances,carbon trading markets are developing rapidly in many countries and regions,demanding more attention to compliance strategy issues for emission-intensive *** this study,we build a dynamic programming model in search of the optimal emission trading and technology investment decisions for a make-to-order company faced with a stochastic demand under emission trading *** a comprehensive analysis of the proposed model,we find that an optimal emission permit level,which increases in carbon penalty and decreases in carbon price,exists in each *** for the abatement technology investment decision,the firm should invest only ff the investment cost per unit of abatement effort is less than a certain threshold,which increases in carbon penalty and carbon *** the basis of a two-period dynamic programming model,we further explore the problem of investment *** show how optimal investment decisions are influenced by the speed of technology progress under different *** findings are important for firms to choose the time of investment depending on specific situations.

关键词： Low-carbon emission trading compliance strategy investment-timing

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Boosted Electrocatalytic Glucose Oxidation Reaction on Noble-Metal-Free MoO_(3)-Decorated Carbon Nanotubes

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Transactions of Tianjin University 2024年第1期30卷 63-73页

作者： yu-Long Men ning Dou Yiyi Zhao Yan huang Lei Zhang Peng Liu Department of Chemical Engineering School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Thyroid Breast and Vascular Surgery Shanghai Fourth People’s Hospital Affi liated to Tongji University School of MedicineShanghai 200081China Department of Vascular Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China

Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell ***,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge process to prepare a noblemetal-free MC-60 catalyst containing MoO_(3),Mo_(2)C,and a Mo_(2)C–MoO_(3)*** the GOR,MC-60 shows activity as high as 745μA/(mmol/L cm^(2)),considerably higher than those of the Pt/CNT(270μA/(mmol/L cm^(2)))and Au/CNT catalysts(110μA/(mmol/L cm^(2))).In the GOR,the response minimum on MC-60 is as low as 8μmol/L,with a steady-state response time of only 3 ***,MC-60 has superior stability and anti-interference ability to impurities in the *** better performance of MC-60 in the GOR is attributed to the abundant Mo sites bonding to C and O atoms at the MoO_(3)–Mo_(2)C *** Mo sites create active sites for promoting glucose adsorption and oxidation,enhancing MC-60 performance in the ***,these results help to fabricate more effi cient noble-metal-free catalysts for the fabrication of glucose-based biofuel cells.

关键词： Interface eff ect Electrocatalysis Molybdenum oxide Glucose Oxidation reaction

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Virtual Reality:A State-of-the-Art Survey

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International Journal of Automation and computing 2009年第4期6卷 319-325页

作者： ning-ning Zhou yu-Long Deng School of Computing Nanjing University of Posts and Telecommunications Nanjing 210003 PRC State Key Laboratory of Software Development Environment Beihang University Beijing 100191 PRC

This paper presents a survey on virtual reality systems and provides an in-depth understanding toward the notion of immersion, according to the semantic meanings of the terms ＂virtual＂ and ＂reality＂. The paper analyses the structure and functions of a virtual reality system and takes the three dimensional display as the immersive medium to identify the key issues for construction of virtual environments. The paper also reviews the development of virtual reality technology and introduces new image processing techniques into the design of virtual reality systems and virtual environments.

关键词： Virtual reality immersion virtual reality image processing technology

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Magnetotransport properties of graphene layers decorated with colloid quantum dots

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Chinese Physics B 2019年第6期28卷 361-365页

作者： Ri-Jia Zhu yu-Qing huang Jia-yu Li ning Kang Hong-Qi Xu School of Physics Dalian University of TechnologyDalian 116024China Beijing Key Laboratory of Quantum Devices Key Laboratory for Physics and Chemistry of Nanodevices and Department of ElectronicsPeking UniversityBeijing 100871China Division of Solid State Physics Lund UniversityP.O.Box 118S-22100 LundSweden

The hybrid graphene-quantum dot devices can potentially be used to tailor the electronic, optical, and chemical properties of graphene. Here, the low temperature electronic transport properties of bilayer graphene decorated with PbS colloid quantum dots(CQDs) have been investigated in the weak or strong magnetic fields. The presence of the CQDs introduces additional scattering potentials that alter the magnetotransport properties of the graphene layers, leading to the observation of a new set of magnetoconductance oscillations near zero magnetic field as well as the high-field quantum Hall *** results bring about a new strategy for exploring the quantum interference effects in two-dimensional materials which are sensitive to the surrounding electrostatic environment, and open up a new gateway for exploring the graphene sensing with quantum interference effects.

关键词： graphene colloid quantum dots quantum Hall effect Aharonov–Bohm oscillations

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Interior non-uniformity of acoustically excited oscillating gas bubbles

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Journal of Hydrodynamics 2019年第4期31卷 725-732页

作者： yu-ning Zhang Xiao-fei Li Zhong-yu Guo Key Laboratory of Condition Monitoring and Control for Power Plant Equipment (Ministry of Education) School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China Key Labor at oiy of Fluid and Power Machinery Ministry of Education Xihua IJnivarsily Chengdu 610039 China College of Mechanical and Transportation Engineering China University of Petroleum-Beijing Beijing 102249 China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-Beijing Beijing 102249 China

In the present paper, the interior non-uniformity of oscillating gas bubbles in liquids under an acoustic field is theoretically investigated, as well as the temperature non-uniformity in the surrounding liquid. The pressure, the density and the temperature inside the gas bubbles are quantitatively predicted for a wide range of bubble Mach numbers. It is shown that the bubble interior non-uniformity increases significantly with the increase of the bubble Mach number. In the case of a large Mach number, the values of aforementioned paramount parameters at the bubble center are significantly larger than those at the bubble interface. Except for a very thin layer close to the bubble interface, the effects of the temperature non-uniformity in the bulk liquid could be safely ignored.

关键词： Cavitation gas bubbles acoustic field radial oscillation non-uniformity Mach number

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