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Numerical study of threshold gain behavior for a THz random laser in a two-dimensional active disordered medium with a three-level atomic system

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Chinese Science Bulletin 2011年第25期56卷 2664-2667页

作者： liu Yong liu jinsong WANG KeJia Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Tech-nology Wuhan 430074 China

By numerically solving Maxwell's equations and rate equations in a two-dimensional (2D) active random media made of ruby grains with a three-level atomic system, the threshold gain behavior for a THz random laser is investigated. The spectral intensity variation with the pumping rate is calculated for both the transverse magnetic (TM) field and the transverse electric (TE) field. The computed results show that THz random lasing could occur in a 2D disordered medium for both the TM and TE cases. Further analysis reveals that the THz lasing threshold for TM fields is lower than that for TE fields.

关键词：三能级原子系统激光阈值无序介质随机介质太赫兹数值研究行为增益

Pn-wave velocity and anisotropy of the western Sichuan and Longmen Mountain region,China

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Science China Earth Sciences 2010年第11期53卷 1665-1670页

作者： Xu Yi Li ZhiWei Huang RunQiu liu JianHua liu jinsong Chinese Acad Sci Inst Geol & Geophys Key Lab Petr Resources Res Beijing 100029 Peoples R China Chengdu Univ Technol State Key Lab Geohazard Prevent & Geoenvironm Chengdu 610059 Peoples R China

Pn-wave velocity and anisotropy beneath the western Sichuan and adjacent region are inverted by a tomography method using arrival data from earthquakes recorded by the Sichuan Earthquake Network. It is followed by an analysis of the uppermost mantle structure of the Longmen Mountain region and the deep tectonics of the Ms8.0 earthquake in Wenchuan. Our results reveal a prominent velocity contrast across the Longmenshan fault: low velocities in the Songpan-Ganzi mountain range and high velocities in the Sichuan basin. They indicate that the Songpan-Ganzi mountain range is underlain by a weak uppermost mantle, which is easy to create ductile flow, whereas the Sichuan basin has a mechanically strong uppermost mantle. These features reflect a difference of the lithospheric mantle beneath tectonically active mountain range and stable basin. The boundary between the high and low velocities is coincident with the Longmenshan fault. Bordered by Wenchuan, the northern part of the boundary is parallel to the fault belt and aftershock distribution, but the southern part of the boundary deviates from the fault belt and is bent toward the Sichuan basin. The Ms8.0 earthquake in Wenchuan is located at the flexural part between them, where a strong heterogeneity is shown in the velocity variation across and parallel to the boundary. This area is reasonably believed as a potential location for regional stress accumulation and release in the Longmen Mountain region, reflecting a prominent character in the deep structure around Wenchuan. Pn-wave anisotropy reveals the mantle flow that is consistent with the eastward movement of the Tibetan Plateau. This process provided deep dynamic sourse for tectonic deformation in the Longmen Mountain region and for the occurrence of the Wenchuan Ms8.0 earthquake, but it is clearly affected by the strong lithosphere of the Sichuan basin. There is no correlation between the Pn-wave anisotropy and the Longmenshan fault, hence, this fault system is on

关键词： western Sichuan Longmen Mountain Pn velocity anisotropy Wenchuan earthquake

Threshold gain properties of lasing modes in ID disordered media optically pumped by femtosecond-lasing pulse

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Frontiers of Optoelectronics 2011年第4期4卷 387-392页

作者： Yong liu jinsong liu Wuhan National Laboratory for Optoelectronics College of Optoelectronic Science and EngineeringHuazhong University of Science and Technology Department of Physics and Electronics Hubei University of Education

By numerically solving Maxwell's equations and rate equations, a comprehensive calculation on spectrum intensity and spectral widths of three localized modes via different pumping rates in one-dimensional(1D) disordered medium is investigated, in which pumping rate is described by a time function with duration of 80 *** spectral intensities varying with the peak value of femtosecond(fs) pumping pulse are calculated in the same disordered medium, and the calculated spectral intensities are compared with those with fixed pumping(simulation time is 6 ps). These results show that excited modes with fs pulse pumping rates are only slightly different from those with fixed pumping(picosecond(ps) pulse), which suggests the excited modes largely depend on the medium rather than the pumping rate at least for those of which pumping rates are fs and ps. At last, lifetimes of three excited modes are calculated. It is found that there is a certain corresponding relation between the mode's lifetime and its threshold-pumping rate, which is the longer lifetime with lower threshold.

关键词： one-dimensional (1D) disordered medium lasing pumping rates localized modes

Seismic tomography of the crust and upper mantle in the Bohai Bay Basin and its adjacent regions

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Science China Earth Sciences 2007年第12期50卷 1810-1822页

作者： ZHANG Ling liu jinsong HAO TianYao liu JianHua XU Yi Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Gocad Research Group Rue Doyen M. Roubault 54501 Nancy France Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

In the Bohai Bay Basin and its adjacent regions(112°―124°E,34°―42°N),there exists abundant gas-petroleum while modern inter-plate seismic activity is *** the tectonic structure of this region is very complicated,plenty of geological,geophysical and geochemical data and results are obtained through previous *** the basis of absorbing previous results,especially various kinds of geological and geophysical results,we collect and process the arrival time of P-wave phases of local events and tele-seismic events recorded by the station within this region from 1978 to 2004,build the responding initial model,and image the velocity structure of the crust and upper mantle of this region via *** perturbation images of various depths and velocity profiles imply that the velocity structure of the crust and upper mantle in the Bohai Bay Basin and its adjacent regions is mainly influenced by the surface tectonic units,and is characterized by "Stripped along east-west,and zoned along south-north";some large-scaled faults penetrate Moho and lithosphere,and provide the channels for the basic lava or hot mass upwelling from the mantle.

关键词： Bohai Bay Basin, tomography, crust and upper mantle

Cache Coherency Design in Pentium Ⅲ SMP System

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Wuhan University Journal of Natural Sciences 2006年第2期11卷 360-364页

作者： liu jinsong ZHANG Jiangling GU Xiwu Key Laboratory of Data Storage System Huazhong University of Science and Technology Wuhan 430074 Hubei China

This paper analyzes cache coherency mechanism from the view of system. It firstly discusses caehe-memory hierarchy of Pentium Ⅲ SMP system, including memory area distribution, cache attributes control and bus transaction. Secondly it analyzes hardware snoopy mechanism of P6 bus and MESI state transitions adopted by Pentium Ⅲ. Based on these, it focuses on how muhiprocessors and the P6 bus cooperate to ensure cache coherency of the whole system, and gives the key of cache coherency design.

关键词： snoop cache coherency MESI protocol P6bus Pentium Ⅲ SMP system

Polarization-dependent difference of the power spectra from two-dimensional random media with different shapes

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Chinese Science Bulletin 2009年第18期54卷 3215-3219页

作者： liu Hai liu jinsong LU JianTao WANG KeJia Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Sci-ence and Technology Wuhan 430074 China School of Information and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China

Polarization-dependent difference of the power spectra from a set of two-dimensional (2D) passive random media is investigated by simultaneously solving Maxwell’s equations for both transverse magnetic (TM) and transverse electric (TE) fields. The random media have the same random constitution but different shapes. Results show that both two polarized states are morphology dependent, and the variety of the shapes has more influence on the selection of TM polarized modes than that of TE polarized modes. Such polarization-dependent difference of morphology property presents a new modeselecting technique for random lasers.

关键词：随机介质功率谱形状二维偏振依赖性麦克斯韦方程组极化状态

Tectonic Framework and Deep Structure of South China and Their Constraint to Oil-Gas Field Distribution

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 170-178页

作者： WANG Qingchen liu jinsong DU Zhili CAI Liguo State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics the Chinese Academy of Sciences Beijing 100029 China Petroleum Exploration and Production Research Institute SinoPec Beijing 100083 China

South China could be divided into one stable craton, the Yangtze Craton （YzC）, and several orogenic belts in the surrounding region, that is the Triassic Qinling-Dabie Orogenic Belt （QDOB） in the north, the Songpan-Garze Orogenic Belt （SGOB） in the northwest, the Mesozoic-Cenozoic Threeriver Orogenic Belt （TOB） in the west, the Youjiang Orogenic Belt （YOB） in the southwest, the Middle Paleozoic Huanan Orogenic Belt （HOB） in the southeast, and the Mesozoic-Cenozoic Maritime Orogenic Belt （MOB） along the coast. Seismic tomographic images reveal that the Moho depth is deeper than 40 km and the lithosphere is about 210 km thick beneath the YzC. The SGOB is characterized by thick crust （〉40 km） and thin lithosphere （〈150 km）. The HOB, YOB and MOB have a thin crust （〈40 km） and thin lithosphere （〈150 km）. Terrestrial heat flow survey revealed a distribution pattern with a low heat flow region in the eastern YzC and western HOB and two high heat flow regions in the TOB and MOB respectively. Such a ＂high-low-high＂ heat flow distribution pattern could have resulted from Cenozoic asthenosphere upwelling. All oil-gas fields are concentrated in the central part of the YzC. Remnant oil pools have been discovered along the southern margin of the YzC and its adjacent orogenic belts. From a viewpoint of geological and geophysical structure, regions in South China with thick lithosphere and low heat flow value, as well as weak deformation, might be the ideal region for further petroleum exploration.

关键词： deep structure heat flow petroleum seismic tomography South China

Relationships between interspecific differences in the mass of internal organs,biochemical markers of metabolic activity,and the thermogenic properties of three smallpasserines

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Chinese Birds 2016年第2期7卷 116-124页

作者： Minlan Bai Xujian Wu Kejing Cai Weihong Zheng jinsong liu School of Life and Environmental Sciences Wenzhou University Zhejiang Provincial Key Lab for Subtropical Water Environment and Marine Biological Resources Protection

Background:The capacity for thermogenesis is considered part of an animal's adaptive strategy for survival,and basal metabolic rate(BMR) is one of the fundamental physiological standards for assessing the energy cost of thermoregulation in *** has been shown to be a highly flexible phenotypic trait both between,and within,species,but the metabolic mechanisms involved in the regulation of BMR,which range from variation in organ mass to biochemical adjustments,remain *** this study,we investigated the relationship between organ mass,biochemical markers of metabolic tissue activity,and thermogenesis,in three species of small passerines:wild Bramblings(Fringilla montifringilla),Little Buntings(Emberiza pusilla) and Eurasian Tree Sparrows(Passer montanus),caught in Wenzhou,southeastern ***:Oxygen consumption was measured using an open-circuit respirometry *** state-4 respiration and cytochrome c oxidase(COX) activity in liver and pectoral muscle were measured with a Clark ***:Our results show that Eurasian Tree Sparrows had significantly higher BMR,digestive organ mass,mitochondrial state-4 respiration capacity and COX activity in liver and muscle,than Bramblings and Little ***,interspecific differences in BMR were strongly correlated with those indigestive tract mass,state-4 respiration and COX ***:Our findings suggest that the digestive organ mass,state-4 respiration and COX activity play an important role in determining interspecific differences in BMR.

关键词： Basal metabolic rate(BMR) Cytochrome c oxidase(COX) State-4 respiration Fringilla montifringilla Emberiza pusilla Passer montanus

Temperature effects of dark solitons on the self-deflection of bright solitons in a separate bright-dark soliton pair

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Chinese Science Bulletin 2007年第6期52卷 725-731页

作者： ZHANG GuangYong liu jinsong ZHANG HuiLan WANG Cheng liu ShiXiong Institute of Optoelectronics Science and Engineering State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Physics China University of Geosciences Wuhan 430074 China

Based on the theory of one-dimensional separate soliton pairs formed in a serial photorefractive crystal circuit, we investigated the temperature effects of the dark soliton on the self-deflection of the bright soliton in a bright-dark soliton pair. The numerical results obtained by solving the nonlinear propaga-tion equation showed that the bright soliton moves on a parabolic trajectory in the crystal and its spa-tial shift changed with the temperature of the dark soliton. The higher the temperature of the dark soli-ton was, the smaller the spatial shift of the bright soliton was. The self-bending process was further studied by the perturbation technique, and the results were found to be in good agreement with that obtained by the numerical method.

关键词：暗孤子明孤子自偏转明暗孤子对温度效应