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Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

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chinese Science Bulletin 2003年第B6期48卷 42-48页

作者： FU Mingzuo~(1,2.3., LI Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography. State Oceanic Administration, Qingdao 2.6061.{3. 2. institute of Oceanology, {3. Academy of Sciences, Qingdao 2.6071.{3. 3. Graduate School, {3. Academy of Sciences, Beijing 10003..{3. Key Laboratory of Marine Sedimentology and Environmental Geology First institute of Oceanography State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School Chinese Academy of Sciences Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2. eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3. the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3.& PAN Liuzhan1, 2.1. institute of Laser Physics and Chemistry, Sichuan University, Chengdu 610064, china 2. Department of Physics, Luoyang Normal College, Luoyang 47102., china 3. State Key Laboratory of Laser {3., Huazhong University of Science and {3., Wuhan 43.074, china Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 institute of Laser Physics and Chemistry Sichuan University Chengdu China State Key Laboratory of Laser technology Huazhong University of Science and Technology Wuhan China Department of Physics Luoyang Normal College Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Carbon and hydrogen isotopic characteristics of natural gases from the Luliang and Baoshan basins in Yunnan Province, china

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Science china Earth Sciences 2006年第9期49卷 938-946页

作者： XU Yongchang1, LIU Wenhui2. SHEN Ping1, WANG Wanchun1, WANG Xiaofeng1, Tenger1, YAN Yaomin3.& LIU Ruobin3.1. Lanzhou Center of Oil & Gas Resources, institute of Geology and Geophsics, chinese Academy of Sciences, Lanzhou 73.000,{2. 2. Research institute of Petroleum Exploration and Production, SINOPEC, Beijing 100083.{2. 3. South Branch of Petroleum Exploration and Production Company, SINOPEC, Kuming 650000,{2. Lanzhou Center of Oil & Gas Resources Institute of Geology and Geophsics Chinese Academy of Sciences Lanzhou China Research institute of Petroleum Exploration and Production SINOPEC Beijing China South Branch of Petroleum Exploration and Production Company SINOPEC Kuming China

The Luliang and Baoshan basins of Yunnan Province are two small-sizedcontinental oil/gas-bearing sedimentary basins, which were developed at the bases of theCarboniferous and Devonian systems during the Late Tertiary, covering an area of 3.0} km^2.and 2.4km^2. respectively. Since the 1990s, there have been discovered small-sized natural gas pools inthese two basins. The natural gases are composed mainly of hydrocarbon gases, with nonhydrocarbonsaccounting for less than 2.. Of the hydrocarbon gases, methane accounts for more than 99%, and thecomponents above C_2.account for less than 0.2.. On the basis of previous studies of geologicalbackground, the composition of natural gases and their carbon isotopic composition, it has beendefined that these two gas pools are of bacterial origin. In this work we have comprehensivelymeasured the carbon and hydrogen isotopic composition of natural gases from these two basins andhave gone into the details of the mechanism of gas generation. The δ^(13.C_1 values of naturalgases from the Luliang Basin are within the range of -72.1 per thousand - -73.3.per thousand, andthe δD_(CH_4) values, -2.2.per thousand - -2.4 per thousand, indicating that the bacterial gasgeneration is dominated by the way of CO_2.reduction. It has been evidenced that undercontinental-facies fresh water conditions there did occur the CO_2.reduction as a process ofbacterial gas generation. The δ^(13.C_1 values of natural gases from the Baoshan Basin are withinthe range of - 62.5 per thousand - -63.5 per thousand, and the δD_(CH_4) values, -2.2.per thousand- -2.0 per thousand. These isotopic characteristics are fallen into transitional phase of acetatefermentation and CO_2.reduction as defined by Whiticar et al. (1986). An important discovery in theLuliang Basin is the carbon isotopic composition of ethane of purely biogenetic origin, i.e., itsδ^(13.C_2.values are within the range of - 61.2.per thousand - - 66.0 per thousand. These carbonisotopic values have been r

关键词： bacterial gas, carbon and hydrogen isotope, CO2 reduction, acetate fermentation.

Measurement of the linear electro-optic coefficient of a minute cBN sample

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Science china(Technological Sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1, , MA Haitao1, JIA Gang1, CHEN Zhanguo1 2.& ZHANG Tiechen3.1. College of Electronic Science and Engineering, State Key Laboratory on Integrated Optoelectronics, Jilin University, Changchun 13.02., china 2. Mudanjiang Normal institute, Mudanjiang 157012. china 3. State Key Laboratory of Superhard Materials, Jilin University, Changchun 13.012. china College of Electronic Science and Engineering State Key Laboratory on Integrated Optoelectronics Jilin University Changchun China Mudanjiang Normal institute Mudanjiang China State Key Laboratory of Superhard Materials Jilin University Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.17×10?14 m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.

Study on growth and properties of novel γ-LiAlO_2.substrate

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Science china(Technological Sciences) 2006年第2期49卷 188-193页

作者： ZOU Jun1,2. ZHOU Shengming1, XU Jun1 & ZHANG Rong3.1. Shanghai institute of Optics and Fine Mechanics, chinese Academy of Sciences, Shanghai 2.1800,{2. 2. Graduate School of chinese Academy of Sciences, Beijing 10003.,{2. 3. Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 2.0093.{2. Shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China Graduate School of chinese Academy of Sciences Beijing China Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing China

Transparent γ-LiAlO2.single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O2.atmosphere at 1100°C for 70 h became opaque and Li-poor phase (LiAl5O8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 3. arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O2.atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 196 nm absorption peak was caused by Li vacancies and the 73. nm peak was caused by O vacancies.

关键词： γ-LiAlO2 crystal, scanning electron micrograph (SEM), absorption spectra.

Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. Lanzhou institute of Geology, chinese Academy of Sciences, Lanzhou 73.000,{2. 2. Earthquake Research institute of Lanzhou, SSB, Lanzhou 73.000,{2. 3. institute of Oceanology, chinese Academy of Sciences, Qingdao 2.6071,{2. Lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of Lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

Simulation of energy and water balance in Soil-Vegetation-Atmosphere Transfer system in the mountain area of Heihe River Basin at Hexi Corridor of northwest china

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Science china Earth Sciences 2005年第4期48卷 538-548页

作者： KANG Ersi1, CHENG Guodong1, , SONG Kechao1, JIN Bowen1, , LIU Xiande3.2.3.& WANG Jinye3.1. Cold and Arid Regions Environmental and Engineering Research institute, chinese Academy of Sciences, Lanzhou 73.000,{2. 2. State Key Laboratory of Frozen Soil Engineering, chinese Academy of Sciences, Lanzhou 73.000,{2. 3. Academy of Water Resources Conservation Forest of Qilian Mountains, Gansu Province, Zhangye 73.000,{2. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China State Key Laboratory of Frozen nSoil Engineering Chinese Academy of Sciences Lanzhou China Academy of Water Resources Conservation Forest of Qilian Mountains Gansu Province Zhangye China

In the mountain area of inland Heihe River Basin at Hexi Corridor of northwest china during the vegetation growing season from May to September, the Simultaneous Heat and Water (SHAW) model of Soil-Vegetation-Atmosphere Transfer (SVAT) system is applied to simulating and studying energy and water balance of the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope and the grassland at the sun-facing slope. The simulation of energy balance indicates that net radiation of the grass- land at the sun-facing slope is more than that of the Picea crassifolia forest and the grassland by the forest at the shaded slope. The energy outgoing components are the first latent heat and next sensible heat from the grassland both at the shaded slope and the sun-facing slope, but those at the former are less. The energy outgoing components are the first sensible heat and next latent heat from the Picea crassifolia forest. The composition and distribution of energy in the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope make the soil layer receive less energy, which therefore, especially the forest possesses the energy conditions for soil water conservation. The simulation of water balance indicates that the water loss of the grassland at the sun-facing slope is mainly caused by soil evaporation, while evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is less than that of the grassland at the sun-facing slope. Half of the evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is consumed by transpiration. After precipitation, the soil water storage is increased much more for the Picea crassifolia forest and also more for the grassland by the forest at the shaded slope. Therefore the shaded slope vegetation, especially the forest is favorable for soil water s

关键词： inland rivers, mountain vegetation zone, Soil-Vegetation-Atmosphere Transfer (SVAT) system, energyand water balance, simulation.

Singular Integral Equations with Cosecant Kernel in Solutions with Singularities of High Order

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Wuhan University Journal of Natural Sciences 2005年第2期10卷 339-343页

作者： HAN Hui-li 1,2.,DU Jin-yuan 1,3.1. School of Mathematics and Statistics, Wuhan University, Wuhan 43.072. Hubei, china 2. School of Mathematics and Computer, Ningxia University, Yinchuan 75002., Ningxia, china 3. Department of Mathematics, Hubei {2. for Nationalities, Enshi 445000, Hubei, china School of Mathematics and Statistics Wuhan University Wuhan Hubei China School of Mathematics and Computer Ningxia University Yinchuan Ningxia China Department of Mathematies Hubei Institute for Nationalities Enshi Hubei China

We have discussed and solved the boundary value problem with period 2.π and the singular integral equation with kernel csc t-tv/a in solution having singularities of high order, where the smooth contour of integratio... 详细信息

关键词： boundary value problem singular integral equation the singularities of high order

Distribution of molluscan remains in the sediment of the Chukchi Sea and its vicinity, the Arctic

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Acta Oceanologica Sinica 2003年第4期22卷 607-619页

作者： Gao Aiguo 1,2. Xu Fengshan3. Sun Haiqing 1,2. Li Lon1 1. First institute of Oceanography, State Oceanic Administration, Qingdao 2.6061,china. 2. Key Laboratory of Marine Sedimentology and Environmental Geology, State Oceanic Administration, Qingdao 2.6061,china 3. institute of Oceanology, chinese Academy of Sciences, Qingdao 2.6071,china First institute of Oceanography State Oceanic Administration Qingdao 266061 China institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Lab. Mar. Sedimentol./Environ. State Oceanic Administration Qingdao 266061 China

The result of an analysis of mollusca remains collected from the Chukchi Sea, Beaufort Sea and Bering Sea in the First chinese National Arctic Research Expedition, from July to September, 1999 is presented. Seventeen species of mollusca have been identified, which belong to two classes: Bivalvia and Gastropoda. The compositions of the mollusca are very simple. According to the distribution pattern two groups may be distinguished among molluscan species. The Pan-Arctic and circumboreal group comprises Nuculana pernula, ***, Nucula bellotii, Astarte montagui, Seripes groenlandicus, Macoma calcarea, M. moesta alaskana, Liocyrna fluctuosa, Mya pseudoarenaria and Turritella polaris. Three species, Cyclocardia crebricostata, Trichotrois coronata and Argobuccinum oregonense are components of the Pan-Arctic and Pacific boreal group. With regard to feeding habits, detritus feeders dominate. There are 7 species of detritus feeders, i.e., Nuculana pernula, N. radiata, Nucula bellotii, Macoma calcarea, M. moesta alaskana, Macoma sp. and Trichotropis coronata. Detritus feeders are dominant with regard to the numbers of species as well as to the frequency of occurrence. Macoma calcarea is the most abundant species.

关键词： Chukchi Sea Beaufort Sea Bering Sea molluscan remains