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The deep thermal characteristic of continental margin of the northern South china Sea

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Chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate {1., University of Science and Technology of{2., Chinese Academy of Sciences, beijing 1.0039,{2. 2. Institute of Geology, Chinese Academy of Sciences, beijing 1.002.,{2. graduate {1. University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

Prediction method for October 2.03 solar storm

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Science china(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1. 2. 3, WEI Fengsi1. FENG Xueshang1.& ZHONG Dingkun1. 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 1.0080, china 2. {2. school, Chinese Academy of Sciences, beijing 1.0039, china 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1.01. china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China graduate {1. Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1. and 3.1., re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Infrared Galaxies in the Nearby Universe

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Chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1.National Astronomical Observatories,Chinese Academy of Sciences,beijing 1.001.1.china {1.{{1. school of Chinese Academy of Sciences,beijing 1.0049,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate {1. of Chinese Academy of Sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1.37 nearby infrared （IR） galaxies, most of which are brighter than 1..9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 1.^9.5 L⊙ to 1.^1.0}⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 1.^1. L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 1.^1.L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1. Li Yin2. Meng Ya3 and Meng Dazhi2.1. National Laboratory of Pattern Recognition,Institute of Automation, Chinese Academy of Sciences, beijing 1.0080, china 2. College of Applied Sciences, beijing University of Technology, beijing 1.002., china 3. school of Science, beijing Institute of Technology, beijing 1.0081. china) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China school of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Cloning and expression of putative ethylene receptor genes in soybean plant

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Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1.2.3, Lei Gang1.2. Wuriyanghan Hada1.2. Tian Aiguo1. Zhang Jinsong1.and Chen Shouyi1.1. National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, beijing 1.01.1. china 2. {2. school of Chinese Academy of Sciences, beijing 1.0039, china 3. Xinjiang Academy of Agricultural and Reclamation Science, Shihezi 832.00, china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China graduate {1. of Chinese Academy of Sciences Beijing 100039 China Xinjiang Academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1. GmERS1. GmETR2.and GmEIN4. Construction of the phylogenic tree showed that GmETR1.and GmERS1.belong to subfamily I whereas GmETR2.and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

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Science china Earth Sciences 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2. WU Ganguo1,2. WANG Genhou2. ZHANG Weijie2.& SONG Honglin2.1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, china University of Geosciences, Ministry of Education of china, {2. 100083, china 2. school of Earth Sciences and Mineral Resources, china University of Geosciences, {2. 100083, china 1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China 100083 Beijing China 2. {1. of Earth Sciences and Mineral Resources China University of Geosciences 100083 Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 1.4Ma and 1.8MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.

Progress in technology for the 2.05 height determination of Qomolangma Feng (Mt. Everest)

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Science china Earth Sciences 2006年第5期49卷 531-538页

作者： CHEN Junyong1.2. YUAN Janli1.2. GUO Chunxi1.2. ZHANG Yanping1.& ZHANG Peng1.2.1. State Bureau of Surveying and Mapping, beijing 1.0830, china 2. {2. of Geodesy and Geomatics, Wuhan University, Wuhan 430079, china 1. State Bureau of Surveying and Mapping Beijing 100830 China 2. {1. of Geodesy and Geomatics Wuhan University Wuhan 430079 China

In 2.05{1. carried out a new geodetic campaign for the height determination of Qo- molangma Feng——Mt. Everest (QF in short). The technical progresses in geodesy for the 2.05 campaign are presented in the paper. GPS positioning was the key technique in the campaign. After summarizing the experiences and lessons of the GPS positioning on the QF summit in the previous QF height determination campaigns, some measures were taken to raise the accuracy and reliability of the height determination with GPS techniques. In order to raise the accuracy of the height deter- mination of the QF summit with classical geodetic techniques, laser ranging was used together with the trigonometric levelling in the 2.05 campaign. It is the first time in{1. the thickness of the ice-snow layer on the QF summit was measured by ground penetrating radar integrated with GPS. The local gravity field and geoid in the QF area was improved on the basis of earth gravity field model integrated with new ground gravity data, DTM data and GPS leveling data in the QF area. In the 2.05 campaign the normal height and orthometric height (height above sea level) of the snow surface of the QF summit were obtained as 8846.67 m and 8847.93 m respectively. The orthometric height of the rock surface of the QF summit is 8844.43 m,and the thickness of the ice-snow layer on the QF summit is 3.50 m.

关键词： Qomolangma Feng, Mt. Everest, height determination, GPS, gravity field, ground penetrating radar.

Properties and applications of cold supersonic gas jet

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1.2.MA Xinwen1.2.LIU Huiping2.LI Bin1.2.& ZHU Xiaolong1.2.1. Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,china 2. graduate University of Chinese Academy of Sciences,{2. 1.0049,china 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. {1. University of Chinese Academy of Sciences Beijing 100049 China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1.2.3 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071. china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061. china 3. {2. school of the Chinese Academy of Sciences, beijing 1.0039, china 1. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. graduate {1. of the Chinese Academy of Sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.