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Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of china

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science china(Technological {2.) 2006年第z1期49卷 177-188页

作者： WANG Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & WANG Qingli Institute of applied Ecology, chinese academy of sciences, Shenyang 110016,{2. Graduate University of chinese academy of sciences, Beijing 100039,{2. State Key Lab of Systems Ecology, research center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085,{2. Institute of applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University of chinese academy of sciences Beijing 100039 China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast china. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.

Linear theory of the response of Na mixing ratio to gravity waves

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chinese science Bulletin 2003年第15期48卷 1630-1633页

作者： XU Jiyao, JI Qiao & WU Mingliang Laboratory for space Weather, center for space science and applied research,{2., Beijing 100080, china Correspondence should be addressed to Xu Jiyao (e-mail: xurrjy@ ***) Laboratory for space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

The influence of gravity waves on the sodium layer is studied by using a linear photochemical-dynamical coupling gravity wave model. The model includes the background photochemistry and the photochemical reactions in the sodium layer. The amplitude and phase difference of the response of sodium mixing ratio to gravity waves are calculated. The results indicate that the lower part of sodium layer is the most sensitive region responding to gravity waves. The perturbation of sodium mixing ratio is in phase with temperature in the lower part of the layer. However, it is out of phase with temperature fluctuation in the upper part.

关键词：线性理论钠重力波光化学大气层

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1,3) Feng ZHANG~1 Yi ZHANG~1* Jianhua HE~1 Jun HU~(1,2. 1 Shanghai Institute of applied Physics,chinese {2. of sciences,Shanghai 2.1800,china 2.Bio-X Life sciences research center.College of Life science and Biotechnology,Shanghai Jiaotong University,Shanghai 2.0030,china 3 Graduate School of the chinese academy of sciences,Beijing 100049,china Shanghai Institute of applied Physics Chinese Academy of SciencesShanghai 201800 China Graduate School of the chinese academy of sciencesBeijing 100049 China Bio-X Life sciences research {2. College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 2.0 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 2. μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

Numerical simulations of the bi-level and branched structure of intracloud lightning flashes

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science china Earth {2. 2006年第6期49卷 661-672页

作者： TAN Yongbo1, TAO Shanchang1, ZHU Baoyou1, MA Ming2.& LU Weitao2.1. School of Earth and space sciences, University of {2. and Technology of china, Hefei 2.002., china 2. chinese academy of Meteorological sciences, Beijing 100081, china 1. School of Earth and space sciences University of Science and Technology of China Hefei 230026 China 2. chinese academy of Meteorological {2. Beijing 100081 China

Intracloud (IC) lightning flashes have been simulated in fine resolution (12.5 m) by using a bidirectional stochastic lightning parameterization scheme within 2.dimensional domain. The simu-lated results show that the IC flashes have a bilevel channel structure and the altitudes of the hori-zontal channels are at the same heights of potential wells, which are supported by the previous VHF source observations and balloon soundings of electric field profile in the thundercloud. Further con-clusions are: (1) After an IC flash is initiated near the boundary between positve and nagetive charge zone, the negative (or positive) leader tends to propagate into the positive (or negative) charge zone. Both types of positive and negative IC flashes have been reproduced and their polarity depends on the up and down disposition of the positive and negative charge regions. (2. The extension range of leaders is correlative with the cloud charge distribution. The leader is possible to extend through the inverted charge region all over where it is extending, but keeps away from the isolated charge area of the same polarity. (3) The channel structures also depend on the electric potential distributions in the thundercloud. Before propagating into the central area of potential wells, the leader tends to extend along the direction with the maximum of potential gradient. Once extending away from the center of potential wells, the leader tends to extend along the direction with the slowest potential change. (4) The IC flash channels have the fractal feature with fractal dimension 1.45 before leaders pass through the central area of charge regions. The exponent decreases rapidly once leaders extend into the low-density charge regions. (5) The induced charges of opposite polarity are deposited in the leader channels within preexisting positive and negative charge regions during IC flash discharges. This causes a new and complicated charge distribution in the thundercloud, and the potential

关键词： IC, lightning parameterization, branched bilevel structure, fractal feature, propagation tendency.

Pleonaste in Boxian meteorite

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chinese science Bulletin 1998年第19期43卷 1656-1660页

作者： WANG Kuiren and HONG Ji’an Department of Earth and space sciences, University of {2. and Technology of china Advanced research center for Earth sciences and Astronomy, University of {2. and Technology of china, Third World academy of sciences Department of Earth and space sciences University of Science and Technology of China China Advanced research center for Earth {2. and Astronomy University of Science and Technology of China Third World Academy of Sciences Hefei China

There are three kinds of occurrence of pleonaste, a rare meteoritic mineral, totally found in Boxian meteorite. They are as the following: (ⅰ) occurring in the inner circle of the chondrule edge, of which a circle texture is composed; (ⅱ) occurring in the state of inclusions, included in an olivine chondrule, with close paragenesis of wadsleyite; (ⅲ) occurring in the state of porphyry. The chondrule in the first occurrence belongs to CA chondrules. The chemical compositions of pleonaste are heterogeneity except for the atomic ratios of Fe/(Mg+Fe), which can be attributed to the following reasons: (ⅰ) they are congenetic minerals; (ⅱ) the heterogeneity of the compositions of the solar clouds in the early states; (ⅲ) the chondrites are the multiple-stage evolution; (ⅳ) the further proof of Boxian meteorite is an unequilibrium common chondrite.

关键词： rare pleonaste in meteorites found genesis.

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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science china Earth {2. 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3, QU Wenjun1 & CHEN Jiangfeng2.1. National research center of Geoanalysis, Beijing 100037,{2. 2. Laboratory for Earth Material Cycling, School of Earth and space sciences, University of science and Technology of{2., Hefei 2.002.,{2. 3. Institute of Mineral Resource, chinese academy of Geological sciences, Beijing 100037,{2. National research center of Geoanalysis Beijing{2. Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China Institute of Mineral Resource chinese academy of Geological {2. Beijing china

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 833 ± 35 Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 130 ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3). The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

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science china Earth {2. 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2.3 & DING YiHui2.1 chinese academy of Meteorological {2., Beijing 100081, china 2.National Climate center, Beijing 100081, china 3 Graduate University of chinese academy of sciences, Beijing 100049, china 1. chinese academy of Meteorological {2. Beijing 100081 China 2. National Climate center Beijing 100081 China 3. Graduate University of chinese academy of sciences Beijing 100049 China

Based on the Indian and chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern{2.. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South{2. Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

Microsegregation and Improved Methods of Squeeze Casting 2.2. Aluminium Alloy

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Journal of Materials science & Technology 2003年第5期19卷 413-416页

作者： Yong ZHONG, Guoyue SU and Ke YANGThe National Engineering research center, the Institute of Metal research, chinese academy of sciences, Shenyang 110016, china Natl. Eng. Res. Ctr. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The squeeze casting of a 2.2. Al alloy was carried out to investigate the effect on microsegregation in the alloy of the application of pressure followed by diffusion annealing. The experimental results indicate that an optimum applied pressure followed by an optimum diffusion annealing process can markedly reduce the degree of microsegregation and improve the mechanical properties to a degree that can approach the level of forged 2.2. Al alloy.

关键词： 2.2. Al alloy Squeeze casting Microsegregation Diffusion annealing

A comparative study on 3-D solar wind structure observed by Ulysses and MHD simulation

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science Bulletin 2005年第07期50卷 672-678页

作者： FENG Xueshang, XIANG Changqing, ZHONG Dingkun & FAN Quanlin SIGMA Weather Group, Key Laboratory of space Weather Key Labo- ratory of Geospace Environment and Geodesy, Ministry of Education, {2., chinese academy of sciences, Beijing 100080, china SIGMA Weather Group Key Laboratory of Space Weather Key Labo- ratory of Geospace Environment and Geodesy Ministry of Education Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

During Ulysses’ first rapid pole-to-pole transit from September 1994 to June 1995, its observations showed that middle- or high-speed solar winds covered all latitudes except those between ?2.° and +2.° near the ecliptic plane, where the velocity was 300―450 km/s. At poleward 40°, however, only fast solar winds at the speed of 700―870 km/s were observed. In addition, the transitions from low-speed wind to high-speed wind or vice versa were abrupt. In this paper, the large-scale structure of solar wind observed by Ulysses near solar minimum is simulated by using the three-dimensional numerical MHD model. The model com- bines TVD Lax-Friedrich scheme and MacCormack II scheme and decomposes the calculation region into two re- gions: one from 1 to 2. Rs and the other from 18 Rs to 1 AU. Based on the observations of the solar photospheric magnetic field and an addition of the volumetric heating to MHD equations, the large-scale solar wind structure mentioned above is reproduced by using the three-dimensional MHD model and the numerical results are roughly consistent with Ulysses’ observations. Our simulation shows that the initial magnetic field topology and the addition of volume heating may govern the bimodal structure of solar wind observed by Ulysses and also demonstrates that the three-dimensional MHD numerical model used here is efficient in modeling the large-scale solar wind structure.

关键词： Ulysses observation solar wind structure numerical simulation.