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Science china Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2.,HE Jinhai 2.,TAO Shiyan 3.& JIN Zuhui 3.1.{2. academy of Meteorological Sciences,beijing 100081,{3. 2.Nanjing institute of Meteorology,Nanjing 2.0044,{3. 3.institute of Atmospheric Physics,{2. academy of Sciences,beijing 10002.,{3. 1. chinese academy of Meteorological Sciences 100081 Beijing China 2. Nanjing institute of Meteorology 210044 Nanjing China 3. chinese {2. of Sciences Institute of Atmospheric Physics 100029 Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South china Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming3.. South china Sea {2. of Oceanology, chinese {3. of Sciences. Guangzhou 5103.1, china 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental {2., chinese {3. of Sciences, Xi’an 710075, china 3. {2. of Geology and Geophysics, chinese {3. of Sciences, beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china Earth Sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2. XIONG Shangfa3.& HUANG Fengbao1 1. Nanjing institute of Geology and Paleontology,{2. academy of Sciences,Nanjing 2.0008,{3. 2. Anthropology and Sociology Department,Santa Clara University,CA 95053.USA 3. institute of Geology and Geophysics,{2. academy of Sciences,beijing 10002.,{3. Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of Geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 872. a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 872. to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between {2.00 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Discovery of low grade metamorphic volcanic rock sheets within UHP in Dabie Mts. and its implications

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chinese Science Bulletin 1997年第14期42卷 1199-1203页

作者： DONG Shuwen, WANG Xiaofeng and HUANG Dezhi1. chinese academy of Geological Sciences (CAGS),{2.,{3. 2. institute of Geomechanics of CAGS, beijing 100081 china 3. Anhui institute of Geological Sciences, Hefei 2.3}001 chinese academy of Geological Sciences (CAGS) Beijing 100037 China

THE ultrahigh-pressure metamorphic zone (UHP), outcropping in the central and southernDabie Mts. with an area of about 1000 km^2. may be the largest one in the world. The forma-tion and exhumation mechanism of the UHP rocks become a hot point in the study of continen-tal orogen. The first finding of the Shiqiao structural window, which is composed of low

关键词： ultrahigh-pressure metamorphic zone (UHP) low grade metamorphic rock sheets Dabie Mts.

Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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Science china(Technological Sciences) 2005年第z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2.& WANG Jianguo3.. institute of Mechanics, {2. academy of Sciences, {3. 100080, china 2. Graduate School, {2. academy of Sciences, {3. 100060, china 3. Tropical Marine Science institute, National University of Singapore, 10 Kent Ridge Crescent, 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

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3. the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 3.% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

A 12.bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

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Science china(Technological Sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2.3.WANG Zheng1,3.& ZHAO JingWei1,3.1 institute of High Energy Physics,chinese academy of Sciences,{3. 100049,china 2.Graduate University of chinese academy of Sciences,{3. 100049,china 3.Key Lab of Nuclear Detection Technology and Nuclear Electronics of chinese academy of Sciences,{3. 100049,china 1. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of Sciences Beijing 100049 China

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in china the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12.bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

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

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Science china Earth Sciences 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 10003.,{2. 2. Laboratory for Earth Material Cycling, School of Earth and Space Sciences, University of Science and Technology of{2., Hefei 2.0}02.,{2. 3. institute of Mineral resource, chinese academy of Geological Sciences, beijing 10003.,{2. National Research Center of Geoanalysis beijing china Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China institute of Mineral resource {2. {3. of Geological Sciences 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 83. ± 3. Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 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.

The formation and stability of Si_(1-x)C_x alloys in Si implanted with carbon ions

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chinese Science Bulletin 2001年第3期46卷 200-204页

作者： WANG Yinshu, LI Jinmin, JIN Yunfan, WANG Yutian, SUN Guosheng & LIN Lanying1. Department of Physics, beijing Normal University, beijing 100875,{2. 2. {3. of Semiconductors, chinese academy of Sciences, beijing 100083.{2. 3. {3. of Modern Physics, chinese academy of Sciences, Lanzhou 73.000,{2. Department of Physics Beijing Normal University Beijing China institute of Semiconductors Chinese Academy of Sciences Beijing China institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Si1-xCx alloys of carbon (C) concentration between 0.6%-1.0% were grown in Si by ion implantation and high temperature annealing. The formation of Si1-xCx alloys under different ion doses and their stability during annealing were studied. If the implanted dose was less than that for amorphizing Si crystals, the implanted C atoms would like to combine with defects produced during implantation and it was difficult to form Si1-xCx alloys after being annealed at 850℃. With the increment of implanted C ion doses, the lattice damage increased and it was easier to form Si1-xCx alloys. But the lattice strain would become saturate and only part of implanted carbon atoms would occupy the substitutional positions to form Si1-xCx alloys as the implanted carbon dose increased to a certain degree. Once Si1-xCx alloys were formed, they were stable at 950℃, but part of their strain would release as the annealing temperature increased to 1 000℃. Stability of the alloys became worse with the increment of carbon

关键词： ion implantation Si1-xCx alloys stability of Si1-xCx alloys.

High Throughput SNP Genotyping with Two Mini-sequencing Assays

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 379-384页

作者： Chunqing LUO1,2., Libin DENG1#, and Changqing ZENG1,2. The institute of Genetic and Developmental Biology, the chinese {2. of Sciences, {3. 100101, china 2.3. Genomics institute, the chinese {2. of Sciences, {3. 1013.0, china The institute of Genetic and Developmental Biology the Chinese Academy of SciencesBeijing 100101 China beijing Genomics institute the Chinese Academy of SciencesBeijing 101300 China

Two mini-sequencing methods, FP-TDI (template-directed dye-terminator incorporation with fluorescence-polarization) and MassArray (matrix assisted laser desorption ionization time of flight detection mass spectrometry), were optimized. A numeric standard was introduced to evaluate the SNP scoring quality of FP-TDI assay, thus made the optimization work easier. At the same time, using multi-PCR technology, 8-plex genotyping of MassArray assay was successfully carried out, some softwares were developed and the data process of MassArray was highly automated. Then these two methods were applied to high throughput SNP genotyping, the accuracy, efficiency and robustness were compared. The result shows FP-TDI is more sensitive to the concentration of SNPprimer and PCR product, as well as extension cycles, the SNPprimer length of FP-TDI should be 2.–3. bp long, whereas MassArray assay prefers to be as short as only 16 *** 6440 SNP sites of human chromosome 3.were genotyped in a sample of 90 individuals, 4792.sites by FP-TDI assay and 1648 sites by MassArray assay, the success rates of FP-TDI and MassArray were 67.7% and 93.6% respectively. The throughput of MassArray was higher than FP-TDI, and the cost of MassArray was lower, MassArray was more suitable for high throughput SNP genotyping.

关键词： SNP genotyping FP-TDI MassArray high throughput

Some key technics of drop tower experiment device of National Microgravity Laboratory (china) (NMLC)

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Science china(Technological Sciences) 2005年第3期48卷 305-316页

作者： ZHANG Xiaoqian 1 , YUAN Longgen 1 , WU Wendong 1 , TIAN Lanqiao 2.& YAO Kangzhuang 2.1. institute of Engineering Thermophysics, chinese {2. of Sciences, {3. 100080, china 2. institute of Mechanics, chinese {2. of Sciences, {3. 100080, china 1. institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. institute of Mechanics Chinese Academy of Sciences 100080 Beijing China

Drop tower is an important ground based facility for microgravity science experiment. The technical performances of the drop tower NMLC are advanced compared with similar facilities in the US, Germany and Japan. The main components such as drop capsule, deceleration devices, release mechanism present its advantages and creativities.

关键词： drop tower facility,drop capsule,deceleration devices,release mechanism.