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Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3 , HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 Key Laboratory for Particle Astrophysics, institute of High Energy physics, chinese academy of sciences, beijing 100049, china 3 Graduate University of the chinese academy of sciences, beijing 100049, china 4 Department of physics, Nanjing Normal University, Nanjing 210011, china 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Brownian ratchets driven by flashing noise strength

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chinese Science Bulletin 1999年第21期44卷 1956-1961页

作者： ZHAO Tongjun, ZHAN Yong, ZHUO Yizhong and WU XizhenDepartment of Applied Mathematics and physics , Hebei University of Technology , Tianjin 300130, china china institute of Atomic Energy, beijing 102413, china institute of theoretical physics, chinese academy of sciences , beijing 100080, china Corresponding author Dept. of Appl. Math. and physics Hebei University of Technology Tianjin 300130 China china institute of Atomic Energy Beijing 102413 China institute of theoretical physics Chinese Academy of Sciences Beijing 100080 China

The stochastic transport driven by flashing multi-noise sources in a ratchet is studied. The stationary current versus the noise strength and the colored noise correlated time T is obtained . At a fixed flip rate and strength of the colored noises, the novel phenomenon of the current reversal occurs as T reaches a certain value. More than one reversal point exists when

关键词： flashing force ratchet current reversal Langevian equation.

High resistance modulation by the electric field based on La_(0.9)Sr_(0.1)MnO_3/SrTiO_3/Si structure

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Science china(physics,Mechanics & Astronomy) 2009年第9期52卷 1299-1301页

作者： YANG Fang, HE Meng, WEN Juan, JIN KuiJuan, LU HuiBin & YANG GuoZhen beijing National Laboratory for Condensed Matter physics, institute of physics, chinese academy of sciences, beijing 100190, china beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

A field-effect configuration based on La0.9Sr0.1MnO3/SrTiO3/Si structure is fabricated on Si substrate by laser molecular-beam epitaxy. The resistance modulation by electric field of the La0.9Sr0.1MnO3/SrTiO3/Si structure is investigated in detail. An evident resistance modulation effect is observed at 80 K. The channel resistance modulation by field effect reaches 1.4×107% and 2.6×106% when VDS are -2 and -6.5 V, respectively. The ON/OFF ratio of approximately 4000 is obtained. The present results are worthy of further investigations for potential applications of resistance modulation by electrostatic field in the heterostructures consisting of perovskite oxides and Si.

关键词： field effect perovskite oxide thin films resistance modulation

Anomalous dielectric behavior in nanocrystalline γ-Fe_2O_3

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chinese Science Bulletin 1999年第2期44卷 186-189页

作者： YE Xisheng , SHA Jian , CHEN Bin , JIAO Zhengkuan ZHANG LideDepartment of physics, Zhejiang University, Hangzhou 310027, china Northwest institute of Nuclear Technology, Xi’ an 710024, china institute of theoretical physics, chinese academy of sciences, beijing 100080, china institute of Solid State physics, chinese academy of sciences, Hefei 230031, china Department of physics Zhejiang University Hangzhou China Northwst institute of Nuclear Technology Xi’an China institute of theoretical physics Chinese Academy of Sciences Beijing China institute of Solid State physics Chinese Academy of Sciences Hefie China

The measurements of electric capacities and dielectric loss angles for nanocrystalline yFe2O3 under air and vacuum atmospheres have been conducted by using ac LRC method, and the conductivity and the polarization relaxation time have also been calculated from the frequency spectra of real and imaginary parts of the dielectric constants. The anomalous dielectric behavior implies the existence of two kinds of polarization mechanisms with different relaxation times, which are caused by the defects and the dangling bonds in the interfaces, respectively. The experimental and calculated results indicated that the polarization loss and the conductance loss are dominant in air atmosphere and vacuum, respectively.

关键词： nanocrystalline γ-Fe2O3 dielectric behavior polarization mechanism.

Carbon nanotube transistors with graphene oxide films as gate dielectrics

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 828-833页

作者： FU WangYang,LIU Lei,WANG WenLong,WU MuHong,XU Zhi,BAI XueDong & WANG EnGe beijing National Laboratory for Condensed Matter physics,institute of physics,chinese academy of sciences,beijing 100190,china 1. beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Carbon nanomaterials,including the one-dimensional(1-D) carbon nanotube(CNT) and two-dimensional(2-D) graphene,are heralded as ideal candidates for next generation *** essential component for the development of advanced nanoelectronics devices is processing-compatible ***,in analogy to the widespread use of silicon dioxide(SiO2) in silicon microelectronic industry,we report the proof-of-principle use of graphite oxide(GO) as a gate dielectrics for CNT field-effect transistor(FET) via a fast and simple solution-based processing in the ambient *** exceptional transistor characteristics,including low operation voltage(2 V),high carrier mobility(950 cm2/V-1 s-1),and the negligible gate hysteresis,suggest a potential route to the future all-carbon nanoelectronics.

关键词： carbon-based nanoelectronics graphene oxide gate dielectrics

Effect of Li and Ti Additions on Lα(Al)+Mg_2Si Pseudobinary Eutectic Reaction

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Journal of Materials Science & Technology 1997年第6期13卷 487-490页

作者： Shengxu ZHAO Shunpu LI Deqian ZHAO Mingxiang PAN and Xichen CHEN(institute of physics, chinese academy of sciences, beijing 100080, china) institute of physics Chinese Academy of Sciences Beijing 100080 China

Effect of Li and Ti additions on Lα(AI)+Mg2Si pseudobinary eutectic reaction in ternary Al-Mg-Si system has been investigated by thermoanalysis, directional solidification and metallographic techniques in this study. It has been found that Li addition causes decreasing of the volume fraction of Mg2Si, while a little amount of Ti causes to increasing, which is of a great importance to the adjustment of phase constitution and alloy properties. Doping components have little influence on the eutectic temperature.

关键词： Si Al Mg2Si Pseudobinary Eutectic Reaction Effect of Li and Ti Additions on L Li Ti

The effects of shock wave and quasi-traveling wave in the mechanical impact test

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Science china(Technological sciences) 2010年第9期53卷 2535-2541页

作者： WU Mei1,5,SUN ZhongFeng2,ZHANG LuMei3,CHEN Yong1 & JI LinHong4 1 institute of High Energy physics,chinese academy of sciences,beijing 100049,china 2 School of Mathematical sciences,Peking University,beijing 100871,china 3 High School of Central University for Nationalities,beijing 100081,china 4 institute of Mechanical Design,Department of Precision Instruments and Mechanology,Tsinghua University,beijing 100084,china 5 academy of Opto-electronics,chinese academy of sciences,beijing 100190,china 1. institute of High Energy physics Chinese Academy of Sciences Beijing 100049 China5. Academy of Opto-electronics Chinese Academy of Sciences Beijing 100190 China2. School of Mathematical Sciences Peking University Beijing 100871 China3. High School of Central University for Nationalities Beijing 100081 China4. Institute of Mechanical Design Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

It is well-known that the numerical value is always larger than the measured value,amounting to many times,if we calculate the stress of the specimen in the impulse test using the NASTRAN and ANSYS (N-A) *** believe that the impact induces shock wave or quasi-traveling wave in the specimen,which can qualitatively explain the discrepancy of the two *** order to verify it,the Lax-Friedrichs (L-F) scheme is taken to simulate the transmission of shock wave and quasi-traveling wave in *** results show that the action area of the stress wave is small and the action time is very short,so the resulting stress and actual work are not *** addition,the distribution of the impact values obtained by the numerical simulation is in accordance with the trend of the measured impact values.

关键词： aerospace environment test shock wave quasi-traveling wave

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl_6^(2-)-HCl system and its influences on the Pt microemulsion extraction

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Science china Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2,LI ZhiHong3,PAN QingHua1,SUN Yan1,LIU ShaoXuan1,LIU XueXin2,LI WeiHong1,YANG ZhanLan1,WENG ShiFu1,HU TianDou3,XU YiZhuang1 & WU JinGuang1 1 College of Chemistry and Molecular Engineering,Peking University,beijing 100871,china 2 institute of Chemistry,chinese academy of sciences,beijing 100190,china 3 institute of High Energy physics,chinese academy of sciences,beijing 100049,china 1. College of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. institute of Chemistry Chinese Academy of Sciences Beijing 100190 China 3. institute of High Energy physics Chinese Academy of Sciences Beijing 100049 China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

An optimization approach to the similarity criteria of flows and its application

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Progress in Natural Science:Materials International 2006年第3期16卷 241-247页

作者： ZHOU Jifu and LI Jiachun (institute of Mechanics, chinese academy of sciences, beijing 100080, china) [a]institute of Mechanics Chinese Academy of Science Beijing China

In the present paper, we propose an optimization approach to investigate the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables governing complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in agreement with the theoretical law, thus demonstrating the feasibility of the proposed optimization approach. Further explanation is given by analyzing the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may change from different sets of parameters.

关键词： similarity optimization sensitivity analysis complex flows model.