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Chinese Physics B 2013年第7期22卷 533-541页

作者：肖啸鲁远甫于峰崎金雷 shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Chinese university of Hong Kong

A 1550-nm linearly tunable continuous wave （CW） single-mode external cavity diode laser （ECDL） based on a singlecavity all-dielectric thin-film Fabry-Pérot filter （s-AFPF） is proposed and realized in this paper. Its internal optical components as well as their operation mechanisms are introduced first, and then its longitudinal mode output characteristic is theoretically analyzed. Afterwards, we set up the experimental platform for the output characteristic measurement of this tunable ECDL; under different experimental conditions, we execute accurate and real-time measurements for the output central wavelength, output optical power, output longitudinal mode distribution, and the line-width of the tunable ECDL in its tuning process. By summing up the optimal experimental condition from the measured data, we obtain the optimal tunable ECDL relevant parameters： the tunable ECDL has a linear mode-hop-free wavelength tuning region of 1547.2.3 nm-1552.42. nm, a stable output optical power in the range of 40 μW-50 μW, and a stable output longitudinal mode distribution of a single longitudinal mode with a line-width in the range of 100 MHz-150 MHz. This tunable ECDL can be used in environmental gas monitoring, atomic and molecular laser spectroscopy research, precise measurements, and so on.

关键词： thin-film optical properties tunable external cavity diode laser laser spectroscopy

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, china 2. graduate {2. of Chinese Academy of Sciences, Beijing 100049, china 3. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate university of Chinese Academy of Sciences 100049 Beijing China Institute of Geographical Sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Effects of lanthanum and gadolinium on proliferation and differentiation of primary osteoblasts

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Progress in Natural Science:Materials International 2007年第5期17卷 618-623页

作者： Zhang Dawei , Zhang Jinchao , Chen Yao , Yang Mengsu and Yao Xinsheng (Department of Natural Products Chemistry, Shenyang Pharmaceutical university, Shenyang 110016, china {2. Research Institute of City university of Hong Kong, {2. 518057, china Department of Biology and Chemistry, City university of Hong Kong, china Department of Chemistry, College of Chemistry & Environmental Science, Hebei university, Baoding 071002. china Key Laboratory for Research and Development of Traditional Chinese Medicine and Natural Medicine at {2., {2. 518057, china) [a]Department of Natural Products Chemistry Shenyang Pharmaceutical University Shenyang China [b]shenzhen Research Institute of City university of Hong Kong Shenzhen China [c]Department of Biology and Chemistry City University of Hong Kong China [d]Department of Chemistry College of Chemistry & Environmental Science Hebei University Baoding China [e]Key Laboratory for Research and Development of Traditional Chinese Medicine and Natural Medicine at shenzhen Shenzhen China

The effects of La3+ and Gd3+ on the proliferation, differentiation and adipogenic transdifferentiation of rat calvarial osteoblast-like cells (ROB cells) were evaluated by MTT method, measuring the activity of alkaline phosphatase (ALP) and Oil red O measurement. Both of La3+ and Gd3+ inhibited the proliferation of ROB cells at all concentrations (1×10-5, 1×10-6, 1×10-7, 1×10-8, 1×10-9 mol·L-1). La3+ at concentration of 1×10-5mol·L-1 significantly increased the alkaline phosphatase activity of ROB cells up to 3 folds (P<0.01). However, the effects reversed to inhibit at other concentrations. Gd played a negative role in the alkaline phosphatase activity. La3+ inhibited the adipogenic transdifferentiation of ROB cells at all concentrations in a dose-dependent way. However, Gd promoted the adipogenic transdifferentiation of ROB cells at 1×10 and 1×10 mol·L . These findings suggested that the effects of rare earth elements on the proliferation, differentiation and adipogenic transdifferentiation of ROB cells were dependent on their concentrations and species.

关键词： lanthanum gadolinium osteoblast-like cells proliferation differentiation transdifferentiation.

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

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Science china(Technological Sciences) 2005年第z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3 1. Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, china 2. graduate School, Chinese Academy of Sciences, Beijing 100060, china 3. Tropical Marine Science Institute, National university of Singapore, Singapore 1192.0 Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Heterotrophic bacteria of the Dapeng Bay in the South china Sea: community structure,abundance,and the relationships of culturablity with environmental factors

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Acta Oceanologica Sinica 2010年第4期29卷 88-97页

作者： JIANG Fajun HU Zhangli HU Chaoqun South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Guangxi Academy of Sciences Nanning 530007 China College of Life Sciences Shenzhen University Shenzhen 518060 China

The community composition,abundance and culturablity of heterotrophic bacterioplankton in the Dapeng Bay of the South china Sea were investigated by morphological method,bacterial cultivation and biochemical methods over an annual *** and Pseudomonas were the predominant genera among the Gram-negative *** bacterioplankton abundance fluctuated from 2.07×10 8 to 2.44×10 9 cells/dm 3 ,and culturable bacteria abundance ranged between 0.1×10 6 and 16.07×10 6 CFU/dm 3 .The Culturablity of heterotrophic bacteria ranged between 0.01% and 1.31%.The relationship between bacterial culturablity and the environmental factors was also studied in different sites of the Dapeng *** the bay,a significantly positive relationship was evidenced between bacterial culturability and temperature,meanswhile bacterial culturability was significantly inversely related with *** positive relationship was shown at the central bay while a negative relationship was observed at the bay mouth and there was no significant correlation at top bay between bacterial culturablity and chlorophyll a of sea water.A positive relationship was found between culturability and DIN all the bay,but DIP showed a significantly negative relationship with bacterial culturability only at the mouth of the bay.

关键词： heterotrophic bacteria culturable bacteria culturablity environmental factors

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2. & WANG ShiJin1 1 Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190, china 2.graduate {2. of Chinese Academy of Sciences, Beijing 100049, china 1. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China 2. graduate university of Chinese Academy of Sciences Beijing 100049 China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2.04, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2.05 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2.srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 2.-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2. XU Ye1,3, SHEN Zhiqiang1,3 & LI Jingjing1,2.1. Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 2.0030, china 2. graduate School of the Chinese Academy of Sciences, Beijing 100034, china 3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical Observatory and the university of Science and Technology of china, Shanghai 2.0030, china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China graduate School of the Chinese Academy of Sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the university of Science Technology of china Shanghai 200030 China

The 12.O (J=1-0), 13CO (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13CO cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2. masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 2.566+582. in the observing field of S152.S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2. maser simulta- neously.

关键词： star formation cloud core outflow H2. maser

Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

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Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2.3, Wang Jianguo4 and Xue Deqiang2.1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china 2. Shandong Provincial Meteorological Observatory, Jinan 2.0031, china 3. {2. university of Chinese Academy of Sciences, Beijing 100039, china 4. Shandong Provincial Meteorological Bureau, Jinan 2.0031, china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial Meteorological Observatory Jinan 250031 China graduate university of Chinese Academy of Sciences Beijing 100039 China Shandong Provincial Meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

A floral organ moving like a caterpillar for pollinating

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Journal of Systematics and Evolution 2010年第2期48卷 102-108页

作者： 1,3,4Zhong-Jian LIU 1Li-Jun CHEN 1,2.3Ke-Wei LIU 1Li-Qiang LI 1Wen-Hui RAO 1(The National Orchid Conservation Center of china/The Orchid Conservation & Research Center of shenzhen,shenzhen 518114,china) 2.School of Life Sciences,university of Science & Technology of china,Hefei 2.002.,china) 3(The Center for Biotechnology and BioMedicine,graduate School at shenzhen,tsinghua university,shenzhen {12.,china) 4(College of Forestry,South china Agricultural university,Guangzhou 510642.china) (The National Orchid Conservation Center of china/The Orchid Conservation & Research Center of shenzhen Shenzhen 518114 China) (School of Life Sciences University of Science & Technology of China Hefei 230027 China) (The Center for Biotechnology and BioMedicine Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China) (College of Forestry South China Agricultural University Guangzhou 510642 China) *Correspondence: Zhong-Jian LIU *Correspondence: *?Author for correspondence. E-mail: <liuzj@***>.

A new pollination mechanism is reported of an orchid species,Bulbophyllum penicillium,based on a field observation in Southeast Yunnan of *** species has a sensitive lip,and there is a distance of 2.3 mm between it and column *** the lip is touched by a landing insect,it will move up and down or swing left and right continuously,just like a moving *** suck a lip movement,the pollinator,a very small fruit fly (Drosophila sp.) ca.1 mm in height,will be pressed toward the column apex where anther and stigma are located,and then cross-pollination takes *** unique mode of pollination,depending on the movement of lip rather than insect itself,has never been found before in either Orchidaceae or other families of angiosperms.

关键词： pollination mechanism Bulbophyllum penicillium Drosophila lip movement

Terahertz transmission properties of Cr ion implantation glass

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Chinese Optics Letters 2010年第4期8卷 425-427页

作者：苏红周航王世兴陈琼州梁华伟阮双琛 shenzhen Key Laboratory of Laser Engineering College of Electronic Science and Technology Shenzhen University shenzhen Academy of Aerospace Technology

Cr ion implantations in glass with the different doses of D=1.493×10^（17） and 4.976×10^（17） ion/cm^2.are obtained by metal vapor vacuum arc（MEVVA）.The effects of the different Cr ion implanted doses on terahertz（THz） transmission property are analyzed from THz time-domain *** results show that the more the Cr ion implanted dose in the micro-area implantation glasses,the larger the THz transmission except the larger absorption at 0.2. *** is an effect attributed to the coupling of plasmas on both the implantation and the implantation affected zones of the Cr ion implantation glass.

关键词： Chromium Glass Ion implantation Vacuum applications Vapors