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Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2, LI Anchun1, HU Ningjing2,3, FU Yongtao1& MA Zhibang4 1. institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 3. institute of Soil Science, chinese academy of sciences, Nanjing 210008, china 4. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Pentacyclic triterpenoid ketones in peat from Gannan Marsh,china

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chinese Science Bulletin 2001年第17期46卷 1433-1436页

作者： DUAN YiLanzhou institute of geology, chinese academy of sciences, Lanzhou 730000, china Lanzhou institute of geology Chinese Academy of Sciences Lanzhou China

Abundant terrigenous triterpenoid ketones and a series of hopanoid ketones were detected in a peat sample from the recent Gannan Marsh. The identifications of pen-tacyclic triterpenoid ketones are discussed in detail. Based on the compositional features of pentacyclic triterpenoid ketones in the sample, it is proposed that terrigenous triterpenoid kentones originate directly from organisms or are diagenetic oxidation products of their alcohols, and hopanoid ketones are formed from hopanoids (e.g. hopanoid alcohols and hopenes) by chemical and biochemical processes. These data provide evidence for the applied studies of pentacyclic triterpenoid ketones as biomarker compounds.

关键词： Gannan Marsh peat pentacyclic triterpenoid ketones identification biochemistry.

A new approach of cascade utilization of the chemical energy of fuel

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Progress in Natural Science:Materials International 2006年第5期16卷 518-523页

作者： HAN Wei, JIN Hongguang and LIN Rumou ( institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china Graduate School of the chinese academy of sciences, beijing 100080, china) [a]institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China [b]Graduate School of the chinese academy of sciences Beijing China

The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2 % -3 % . The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.

关键词： chemically recuperated gas turbine methane/steam reforming chemical energy level cascade utilization.

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 Ming31. South china Sea institute of Oceanology, chinese academy of sciences. Guangzhou 510301, china 2. State Key Laboratory of Loess and Quaternary geology, Earth Environmental institute, chinese academy of sciences, Xi’an 710075, china 3. institute of geology and geophysics, chinese academy of sciences, beijing 100029, 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.

The discovery of aeschnidiid nymphs (Aeschnidiidae, Odonata, Insecta)

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chinese Science Bulletin 2000年第11期45卷 1031-1038页

作者： ZHANG JunfengNanjing institute of geology and Palaeontology, chinese academy of sciences, Nanjing 210008, china Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China

Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from china, Mongolia, Russia and Brazil and arranged in the family Aeschnidiidae are, in fact, unrelated to this group. All the known five chinese species in four genera which were erected based on fossil nymphs and placed in the family Gomphidae may be transferred in Aeschnidiidae and merged into one alone, the Sinaeschnidia cancellosa. It is a geographically widespread species from the 'Jehol biota' of East Asia and appeared in the latest Late Jurassic age.

关键词： Jehol biota Aeschnidiidae dragonfly nymphs.

DMTB:A comprehensive online resource of 16S rRNA genes,ecological metadata,oligonucleotides,and magnetic properties of magnetotactic bacteria

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chinese Science Bulletin 2011年第6期56卷 476-478页

作者： LIN Wei1,2, LI Bi1,2 & PAN YongXin1,2 1 Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth’s Deep Interior, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2 France-china Bio-Mineralization and Nano-Structures Laboratory, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china Paleomagnetism and Geochronology Laboratory Key Laboratory of the Earth"s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences France-china Bio-Mineralization and Nano-Structures Laboratory Institute of Geology and Geophysics

Magnetotactic bacteria (MTB) are of interest in microbiology, biomineralization, advanced magnetic materials, and bio-geo-sciences because of their ability to form highly ordered intracellular magnetic minerals. Great strides for MTB studies have been made in the past four decades. In this paper we complied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It contains information of 16S rRNA gene sequences, corresponding ecological metadata, oligonucleotides, and magnetic properties of MTB. The comprehensive information contained in DMTB will provide a very useful data resource for researchers from different disciplines. The website of DMTB is at http://***/.

关键词： rRNA基因序列趋磁细菌 16S 网上资源寡核苷酸磁学性质生态磁性材料

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3, GUO Zhengtang2,1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 3. institute of Geomechanics, chinese academy of Geological sciences, beijing 100081, china 1. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 253.1 m sequence varies from 6 to 13 μm and the > 63 μm fraction representsonly 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in Natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( chinese academy of Meteorological Science, beijing 100081, china institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 200032, china) [a]chinese academy of Meteorological Science Beijing China [b]chinese academy of sciences Institute of Geographic sciences and Natural Resources Research Beijing China [c]Mathematics Department Ocean University of China Qingdao China [d]chinese academy of sciences Shanghai Institute of Plant Physiology and Ecology Shanghai China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at Yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china Plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.