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Journal of Systematics and Evolution 2010年第5期48卷 318-325页

作者： Hong-Chun ZHENG Sheng-Wen MA Tuan-Yao CHAI(College of Life Science,graduate university of chinese {3. of sciences,beijing 100049,china) (College of Life Science Graduate University of Chinese Academy of Sciences Beijing 100049 China)

Phytolacca is the biggest and most original genus in Phytolaccaceae and an important genus in plant systematic *** microscopy results show that the Phytolacca americana *** arises from the caulis(floral receptacle).The perisperm and hypostase are simultaneously initiated from the top several layers of cells of chalaza after fertilization,and the perisperm is located between the nucellus and *** the early stages of development,the hypostase cells are thin-walled with dense cytoplasm,clear nuclei,and some reserve ***,at the heart-shaped embryo stage,the hypostase cells are dead and *** main functions of the hypostase may be to maintain cellular division and perisperm growth without delivering nutrient materials to the *** evolutionary picture of placentation in Caryophyllales is also presented.

关键词： hypostase nucellus ovule perisperm Phytolacca placentation.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

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Wuhan university Journal of Natural sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2, 3., LIU Qing 1 1. Chengdu Institute of Biology, chinese academy of sciences, Chengdu 610041, Sichuan,{3. 2. graduate university of chinese academy of sciences, beijing 100049, china 3. academy of Land Reconnaissance and Layout of Sichuan Province , Chengdu 61003., Sichuan, china Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China graduate university of chinese {3. of sciences Beijing China academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2001. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2001. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2001, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Spectral analysis of two solar twins and the colors of the Sun

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Science china(Physics,Mechanics & Astronomy) 2010年第8期53卷 579-585页

作者： ZHAO ZhengShi1,2, CHEN YuQin1, ZHAO JingKun1 & ZHAO Gang1 1 National Astronomical Observatories, chinese academy of sciences, {3. 100012, china 2 graduate university of chinese academy of sciences, beijing 100049, china National Astronomical Observatories Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

High resolution (R^40,000) and high signal-to-noise ratio (>150) spectra of two solar twins, HD14623. and HD19503., are obtained with the Coude Echelle Spectrograph at the 2.16 m telescope of the National Astronomical Observatories of chinese academy of sciences (Xinglong,{3.). Based on the detailed spectrum match, comparisons of chemical composition and chromospheric activity, HD14623. and HD19503. are confirmed that they are similar to the Sun except for lithium abundance, which is higher than the solar value. Moreover, among nine solar twin candidates (including HD14623. and HD19503.) found in the previous works, we have picked out six good solar twin candidates based on newly-derived homogenous parameters, and collected their colors in the Johnson/Cousins, Tycho, 2MASS and Strmgren system from the literature. The average color are (B-V)⊙=0.644 mag, (V-Ic)⊙=0.707 mag, (BT-VT)⊙=0.725 mag, (J-H)⊙=0.288 mag, (H-K)⊙=0.066 mag, (v-y)⊙=1.028 mag, (v-b)⊙=0.619 mag, (u-v)⊙=0.954 mag and (b-y)⊙=0.409 mag, which represent the solar colors with higher precision than previous works.

关键词： Sun-colors Star-atmospheres abundances fundamental parameters

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,{3. graduate School of chinese academy of sciences,beijing 100049,{3. National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate School of chinese academy of {3. Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2）, and soft bursts show no pulse-like profile but have only a dipped profile （type 3.. In terms of the conventional hardness ratio, type 3.sources are indeed generally softer than those of type 1 and type 2, in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences,{3. 2 graduate School of chinese academy of sciences,{3. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate School of chinese academy of {3. Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 3. AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Systematic distortion in cosmic microwave background maps

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： LIU Hao 1,3.&LI TiPei 1,2 1Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,chinese academy of sciences,{3. 100049,china 2Center for Astrophysics,Tsinghua university,{3. 100084,china 3.graduate university of chinese academy of sciences,{3. 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China Center for Astrophysics Tsinghua University Beijing China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

Indian monsoon influences altitude effect of δ^(18)O in precipitation/river water on the Tibetan Plateau

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chinese Science Bulletin 2009年第15期54卷 2724-2731页

作者： YAO TanDong1,2, ZHOU Hang1,3.& YANG XiaoXin1,3.1 Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, chinese academy of sciences, {3. 100085, china 2 State Key Laboratory of Cryosphere sciences, Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, Lanzhou 73.000, china 3.graduate university of chinese academy of sciences, beijing 100049, china Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China State Key Laboratory of Cryosphere sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China graduate university of chinese {3. of sciences Beijing China

The δ 18O variation in precipitation acquired from 28 stations within the network of Tibetan Observation and Research Platform(TORP)is studied, with the focus on the altitude effect of δ 18O in river water during monsoon precipitation in an effort to understand the monsoon influence on isotopic composition in annual river water. It is found that δ 18O in precipitation on the Plateau is influenced by different moisture sources, with significant Indian monsoon influence on δ 18O composition in plateau precipitation and river water. The δ 18O of water bodies in the monsoon domain is generally more depleted than that in the westerly domain, suggesting gradual rainout of southwesterly borne marine moisture in the course of long-distance transportation and lifting over the Himalayas. The lapse rate of δ 18O in river water with altitude is the largest during monsoon precipitation, due to the increased temperature vertical gradient over the southern Plateau region controlled by monsoon circulation. The combination of δ 18O in river water in monsoon (wet) and non-monsoon (dry) seasons shows a larger lapse rate than that in non-monsoon (dry) season alone. As the altitude effect of δ 18O in precipitation and river water on the Tibetan Plateau results from the combined effect of monsoon moisture supply and westerly moisture supply, the δ 18O composition and its altitude effect on the Plateau during monsoon seasons should be considered in the reconstruction of paleoelevation of the Tibetan Plateau.

关键词：印度季风青藏高原降水

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of Opto-Electronics,chinese academy of {3.,beijing 100190,china 2 graduate university of chinese academy of {3.,beijing 100049,china 3.Lanzhou Institute of Chemical Physics,chinese academy of {3.,Lanzhou 73.000,china academy of Opto-Electronics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Compositions of heavy minerals in Northeastern china sandlands and provenance analysis

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Science china Earth sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2 & DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of sciences, {3. 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North china Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern china,garnet,tourmaline

Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2 & WU Budan1,4 1. academy of Mathematics and Systems Science, chinese academy of {3., beijing 100080, china 2. Institute of Computing Technology, chinese academy of {3., beijing 100080, china 3. Institute of Software, chinese academy of {3., beijing 100080, china 4. graduate university of chinese academy of {3., beijing 100049, china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Institute of Software Chinese Academy of Sciences Beijing China Institute of Computing Technology Chinese Academy of Sciences Bejing China graduate university of chinese {3. of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.