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Journal of Environmental Sciences 2011年第3期23卷 353-359页

作者： Min gao LinLi Junxin liu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

We investigated the correlation between performance and the bacteria community composition by H2S and toluene co-treatment. Operation of the bioreactor was divided into four stages, in which the inlet concentration of toluene and H2S were gradually increased. In Stage I, toluene was the sole target compound with an average removal efficiency of 86.49%. After adding HeS in Stage II, removal efficiency of toluene decreased immediately and recovered gradually to 85.96%. When the inlet concentration of toluene and HzS was increased in Stage III and Stage IV, respectively, the average removal efficiency for toluene increased continuously from 86.31% to 87.24%. The elimination capacities of toluene increased with increasing inlet loading rates of toluene and H2S. Results of the PCR-DGGE analysis showed a turnover growth and decline of the microbial populations in the bioreactor. In Stage I, the dominant toluene-degrading bacteria mainly contained Pseudomonas sp. strain PS ＋ and Hydrogenophaga sp. In Stage IV, however, the dominant toluene-degrading bacteria was aciduric bacteria （Clostridium populeti）. The dominant microbial community in the bioreactor enhanced the elimination capacity of toluene, and adding H2S changed the environment of microbial growth, thus resulted in an evolution of dominant microorganisms. Analyses of microbial community and their activities provides valuable information to efficiently enhance simultaneous removal of toluene and H2S in the bioreactor.

关键词： off-gas treatment bacterial community hydrogen sulfate toluene

Influence of the finish rolling temperatures on the microstructure and texture evolution in the ferritic stainless steels

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Acta Metallurgica Sinica(English Letters) 2011年第5期24卷 343-350页

作者： Fei gao Zhenyu liu Haitao liu Guodong WANG The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 China

The influence of the finish rolling temperature on the microstructure and texture evolution of Nb and B micro-alloyed ultra purified Cr17 ferritic stainless steels was investigated. The hot rolled bands were produced by conventional rolling process and the finish rolling at relatively low temperatures or ＂warm rolling＂. The microstructure was observed by optical microscopy, scanning electron microscopy and transmission electron microscopy, and X-ray diffraction was used to characterize the texture evolution processes. The results showed that as compared to conventional hot rolling process, the warm rolling has led to the refined and homogeneous microstructure and uniform recrystallization texture along γ-fiber in final sheets, indicating that the finish rolling at relatively low temperatures can be the effective way to improve significantly the formability of final sheets.

关键词： Ultra purified Cr17 ferritic stainless steel Finish rolling temperature Microstructure Texture

Redundant discrete wavelet transforms based moving object recognition and tracking

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1115-1123页

作者： gao Tao liu Zhengguang Zhang Jun School of Electrical Engineering and Automation Tianjin Univ. Tianjin 300072 P. R. China

A method for moving object recognition and tracking in the intelligent traffic monitoring system is presented. For the shortcomings and deficiencies of the frame-subtraction method, a redundant discrete wavelet transform （RDWT） based moving object recognition algorithm is put forward, which directly detects moving objects in the redundant discrete wavelet transform domain. An improved adaptive mean-shift algorithm is used to track the moving object in the follow up frames. Experimental results show that the algorithm can effectively extract the moving object, even though the object is similar to the background, and the results are better than the traditional frame-subtraction method. The object tracking is accurate without the impact of changes in the size of the object. Therefore the algorithm has a certain practical value and prospect.

关键词： traffic monitoring moving object recognition moving object tracking redundant discrete wavelet.

Revealing the working mechanism of a multi-functional block copolymer binder for lithium-sulfur batteries

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Journal of Energy Chemistry 2021年第8期30卷 1-8,I0001页

作者： Xin He Zhimeng liu Guoping gao Xiaotao liu Michal Swietoslawski Jun Feng gao liu Lin-Wang Wang Robert Kostecki Energy Storage&Distributed Resources Division Lawrence Berkeley National Laboratory1 Cyclotron Road94720 BerkeleyUSA Materials Sciences Division Lawrence Berkeley National Laboratory94720 BerkeleyUSA The Molecular Foundry Lawrence Berkeley National Laboratory94720 BerkeleyUSA Department of Materials Science&Engineering Southern University of Science and Technology(SUSTech)Shenzhen 518055China

The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy ***,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S *** this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S *** performance improvements are attributed to the synergistic effects contributed by the different units of the block *** ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high ***,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume *** enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.

关键词： Lithium sulfur batteries Polymer binder Block copolymer Ultraviolet-visible spectroscopy X-ray absorption spectroscopy

Caryophyllene-type sesquiterpenoids and α-furanones from the plant endophytic fungus Pestalotiopsis theae

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Chinese Journal of Natural Medicines 2020年第4期18卷 261-267页

作者： GUO Long-Fang liu gao-Ran liu Ling State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100039China

Two new caryophyllene-type sesquiterpenoids, pestathenols A(1) and B(2) and one new α-furanone, pestatheranone A(6), along with five known compounds(3–5, 7 and 8) have been isolated from the crude extract of the plant endophytic fungus Pestalotiopsis theae. Their structures were unambiguously established by extensive spectroscopic analyses. The absolute configuration of the 5,6-diol moiety in 1 was assigned using Snatzke’s method. Compounds 1 and 2 showed weak cytotoxicity against HeLa cell line.

关键词： Structure elucidation Sesquiterpenoids Pestalotiopsis theae Cytotoxicity

Synthesis of LiFePO_4 /C as cathode material by a novel optimized hydrothermal method

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Rare Metals 2011年第5期30卷 433-438页

作者： gao Ge liu Aifang HU Zhonghua XU Yuanyuan liu Yafei Department of Chemistry Tongii University Shanghai 200092 China

Olivine LiFePO 4 , as a cathode material for lithium ion batteries, was prepared by a novel optimized hydrothermal method; afterwards, the product mixed with glucose was two-step （350℃ and 700℃） calcinated under high-purity N 2 atmosphere to obtain the LiFePO 4 /C composite. The study on the hydrothermal preparation method, which focused on the influences of molar ratios, initial pH value, reaction temperature, and duration, was made to promote the resultant performances and to investigate the relations between the performances and the reaction conditions. The resultant samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and electrochemical tests, which include charge-discharge, electrochemical impedance spectroscopy, and cyclic voltammetry. The result shows that the optimal hydrothermal condition is to set the Li：Fe：P molar ratio at 3：1：1 and the reaction temperature at 180℃ for 5 h duration with an initial pH value of 7. The optimized sample, with an average particle size of 100 to 300 nm and a discharge capacity of 118.2 mAh·g-1 at 0.1C, exhibits a stable and narrow-gapped charge-discharge platform and small capacity losses after cycles.

关键词： lithium ion batteries cathode materials phosphates olivine carbon deposition hydrothermal synthesis

Simulation study of China's net primary production

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Chinese Science Bulletin 2008年第3期53卷 434-443页

作者： gao ZhiQiang liu JiYuan Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Spatial and temporal distribution of vegetation net primary production(NPP)in China was studied us-ing three light-use efficiency models(CASA,GLOPEM and GEOLUE)and two mechanistic ecological process models(CEVSA,GEOPRO).Based on spatial and temporal analysis(***,seasonally and annually)of simulated results from ecological process mechanism models of CASA,GLOPEM and CEVSA,the following conclusions could be made:(1)during the last 20 years,NPP change in China followed closely the seasonal change of climate affected by monsoon with an overall trend of increas-ing;(2)simulated average seasonal NPP was:0.571±0.2 GtC in spring,1.573±0.4 GtC in summer,0.6±0.2 GtC in autumn,and 0.12±0.1 GtC in *** annual NPP in China was 2.864±1 *** the five models were able to simulate seasonal and spatial features of biomass for different ecological types in *** paper provides a baseline for China's total biomass *** also offers a means of estimating the NPP change due to afforestation,reforestation,conservation and other human activities and could aid people in using for-mentioned carbon sinks to fulfill China's commitment of reducing greenhouse gases.

关键词：中国净初级生产力模型比较时空变化

Quantum Tunneling of Massive Particles from a Garfinkle-Horowitz-Strominger Dilatonic Black Hole

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Communications in Theoretical Physics 2006年第4X期46卷 766-768页

作者： gao Li liu Wen-Biao Department of Physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

Hawking radiation is viewed as a process of quantum tunneling. The massive particles＇ tunneling from Garfinkle-I-Iorowitz-Strominger black hole is investigated. Using Jingyi Zhang＇s de Broglie wave method, we get th... 详细信息

关键词： Hawking radiation quantum tunneling information paradox black hole

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输电线路外破隐患空间距离三维点云测量方法

沈阳工业大学学报 2025年第1期47卷 14-20页

作者：廖如超刘高汪皓成国雄朱凌清华大学机械工程系北京100084 广东电网有限责任公司机巡管理中心广东广州510335 广东电网有限责任公司韶关供电局广东广州510335 广东电网有限责任公司中山供电局广东广州510335

【目的】输电线路容易受到外力破坏,如建筑施工和车辆碰撞等。通过准确测量外破隐患空间距离,可以预警并及时采取措施避免故障发生,进而保障输电线路的安全稳定运行。但在输电线路较长的情况下,区域点云密度不均匀性会明显增加,给计算... 详细信息

【目的】输电线路容易受到外力破坏,如建筑施工和车辆碰撞等。通过准确测量外破隐患空间距离,可以预警并及时采取措施避免故障发生,进而保障输电线路的安全稳定运行。但在输电线路较长的情况下,区域点云密度不均匀性会明显增加,给计算外破隐患空间距离带来困难,同时在噪声点的干扰下,测量误差和转换参数不准确等问题导致故障点与端点之间产生坐标转换误差。为了及时智能化测量输电线路外破故障点与端点之间的距离、快速消除外破故障,提出了一种输电线路外破隐患空间距离三维点云测量方法。【方法】基于点云密度的高程滤波区间,利用kdtree空间结构遍历整幅图像,获取点云数据。对三维点云提取到的输电线路目标图像进行色彩调整、旋转、分辨率调整以及翻转等一系列预处理;当输电线路外破引起不对称短路故障时,结合输电线路的正序电感、电容以及容抗信息,解算目标像素点后的输电线路外破隐患空间距离,分析输电线路两端的正序分量和负序分量,对目标像素点进行解算,消除故障点处不同步相角的影响,构建空间距离测量函数,根据子空间网格点云的最小值和均值之和确定搜索半径,解算目标图像中的像素点,实现对输电线路外破隐患空间距离的精准测量。【结果】所提方法在不同步相角和不同过渡电阻下,测距绝对误差较小,最大值未超过2 m,不存在伪根情况,所测量的空间距离与故障距离最为接近,可实现对输电线路外破隐患精准测距。在恶劣天气或复杂地形条件下,若人员难以到达现场巡检,可通过远程监控点云数据来分析外破隐患空间距离,如果发现某一物体(如正在靠近输电线路的施工机械)与输电线路之间的空间距离逐渐缩小,当达到设定的危险阈值时,系统需要发出预警并及时采取措施避免外破事故的发生。【结论】采用三维点云测量技术对输电线路外破隐患空间距离进行测量,可以实时监测输电线路周围环境,全面准确地掌握输电线路的健康状况。根据实际情况优化巡检策略,重点巡检外破隐患风险较高的区域,减少不必要的巡检工作量,提高运维效率。

关键词：目标像素点输电线路外破隐患空间距离三维点云测距函数不同步相角

MECHANICAL PERFORMANCE OF NANO-CaCO_3 FILLED POLYSTYRENE COMPOSITES

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Acta Mechanica Solida Sinica 2009年第6期22卷 555-562页

作者： Yun gao Luqi liu Zhong Zhang National Center for Nanoscience and Technology Beijing 100190 China

Nano-CaCO3 incorporated polystyrene composites are compounded by twin-screw extrusion. Tensile and compact tensile tests show that the strength and toughness of polystyrene are decreased after the addition of nano-CaCO3 particles. Fracture surface analysis suggests that the defects induced by interfacial debonding and nano-filler agglomerations would be the key factors responsible for the declined strength and toughness. Nevertheless, it has to be stated, if the applied stress is lower than the ultimate strength, the rigid nanoparticles would still stiffen the polymer molecules, and resist polymer chain mobility. Hence, the improved tensile modulus and creep resistance can be obtained with the increasing contents of nanoparticles.

关键词： nanocomposites nanoparticles polymers mechanical properties debonding