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321.
Wang Yunpeng Zhao Changyi Wang Zhaoyun Wang Hongjun Zou Yanrong Liu Jinzhong Zhao Wenzhi Liu Dehan Lu Jialan 《《地质学报》英文版》2008,82(1):197-205
This paper probes the determination of the main gas-generation phase of marine organic mattes using the kinetic method. The main gas-generation phase of marine organic matters was determined by coupling the gas generation yields and rates in geological history computed by the acquired kinetic parameters of typical marine organic matters (reservoir oil, residual bitumen, lowmaturity kerogen and residual kerogen) in both China and abroad and maturity by the EasyRo(%) method. Here, the main gas-generation phase was determined as Ro%=1.4%-2.4% for type Ⅰ kerogen, Ro%=1.5-3.0% for low-maturity type Ⅱ kerogen, Ro%=1.4-2.8% for residual kerogen, Ro%=1.5-3.2% for residual bitumen and Ro%=1.6-3.2% for reservoir oil cracking. The influences on the main gas-generation phase from the openness of the simulated system and the "dead line" of natural gas generation are also discussed. The results indicate that the openness of simulation system has a definite influence on computing the main gas-generation phase. The main gas-generation phase of type Ⅱ kerogen is Ro%=1.4-3.1% in an open system, which is earlier than that in a closed system. According to our results, the "dead line" of natural gas generation is determined as Ro=3.5 % for type Ⅰ kerogen, Ro=4.4-4.5% for type Ⅱ kerogen and Ro=4.6% for marine oil. Preliminary applications are presented taking the southwestern Tarim Basin as an example. 相似文献
322.
Wang T Lu Y Chen C Naile JE Khim JS Park J Luo W Jiao W Hu W Giesy JP 《Marine pollution bulletin》2011,62(8):1905-1914
Perfluorinated compounds (PFCs) in water, sediment, soil, and biota collected from estuarine and coastal areas of the north Bohai Sea, China, were determined by use of HPLC-MS/MS. Significant concentrations of PFCs were found in water (mean: 18.4 ng/l) and biologic samples (fish: 265 ng/g dw), while concentrations of PFCs in soils and sediments were less. The predominately detected compound was perfluorooctanesulfonate (PFOS), with a maximum concentration of 30.9 ng/l in water and 791 ng/g dw in fish. Concentrations of PFCs were significantly greater in the Liaohe River system than other locations, which suggests point sources in this urbanized and industrialized region. PFOS concentrations in water and biota were both less than the reported threshold concentrations. Detection of PFCs at relatively great concentrations in various environmental matrices from this region suggested that further studies characterizing concentrations of PFCs, their sources and potential risk to both humans and wildlife are needed. 相似文献
323.
LI Yong ZHANG Qingwen WAN Guojiang HUANG Ronggui PIAO Hechun BAI Lingyu & LI Lu . State Key Laboratory of Soil Erosion Dryland Farming on the Loess Plateau Institute of Soil Water Conservation Chinese Academy of Sciences Yangling China . Institute of Agro-Environment Sustainable Development Chinese Academy of Agricultural Sciences Beijing China . Institute of Geochemistry Chinese Academy of Sciences Guiyang China 《中国科学D辑(英文版)》2006,49(9):1002-1008
Vegetation is an important factor in maintaining ecological balance and improving eco-environment. For improving environment, vegetation cover, as a substitute for the integrated action of stems and leaves, seems to be a crucial factor. However, recent st… 相似文献
324.
The equatorial response to subtropical Pacific forcing was studied in a coupled climate model.The forcings in the western,central and eastern subtropical Pacific all caused a significant response in the equatorial thermocline,with comparable magnitudes.This work highlights the key role of air-sea coupling in the subtropical impact on the equatorial thermocline,instead of only the role of the "oceanic tunnel".The suggested mechanism is that the cyclonic (anticyclonic) circulation in the atmosphere caused by the subtropical surface warming (cooling) can generate an anomalous upwelling (downwelling) in the interior region.At the same time,an anomalous downwelling (upwelling) occurs at the equatorward flank of the forcing,which produces anomalous thermocline warming (cooling),propagating equatorward and resulting in warming (cooling) in the equatorial thermocline.This is an indirect process that is much faster than the "oceanic tunnel" mechanism in the subtropical impact on the equator. 相似文献
325.
Dongxu YANG Yi LIU Hartmut BOESCH Lu YAO Antonio DI NOIA Zhaonan CAI Naimeng LU Daren LYU Maohua WANG Jing WANG Zengshan YIN Yuquan ZHENG 《大气科学进展》2021,38(1):8-11
The 1st Chinese carbon dioxide(CO2)monitoring satellite mission,TanSat,was launched in 2016.The 1st TanSat global map of CO2 dry-air mixing ratio(XCO2)measurements over land was released as version 1 data product with an accuracy of 2.11 ppmv(parts per million by volume).In this paper,we introduce a new(version 2)TanSat global XCO2 product that is approached by the Institute of Atmospheric Physics Carbon dioxide retrieval Algorithm for Satellite remote sensing(IAPCAS),and the European Space Agency(ESA)Climate Change Initiative plus(CCI+)TanSat XCO2 product by University of Leicester Full Physics(UoL-FP)retrieval algorithm.The correction of the measurement spectrum improves the accuracy(?0.08 ppmv)and precision(1.47 ppmv)of the new retrieval,which provides opportunity for further application in global carbon flux studies in the future.Inter-comparison between the two retrievals indicates a good agreement,with a standard deviation of 1.28 ppmv and a bias of?0.35 ppmv. 相似文献
326.
<正>1 Introduction After the Dongchuan Orogenic movement(Hudsonian Orogeny,ca.1800 Ma±),the tectonic basement layer of the continental crust on the Yangtze massif could have been formed.And then tectonic-magmatic emplacement 相似文献
327.
As a window of insight into the lower crust, high pressure granulite has received much attention since last decade. Yushugou high pressure granulite-peridotite Complex was located in the northeast margin of Southern Tianshan, NW China. Previous ideas agreed that the peridotite unit in Yushugou, combined with the ultramafic rocks in Tonghuashan and Liuhuangshan, represent an ophiolite belt. However, the metamorphic evolution and tectonic mechanism of the Yushugou high pressure(HP) granulite remain controversial. Petrological investigations and phase equilibrium modelling for two representative felsic granulite samples suggest two stages metamorphism of the rocks in Yushugou Complex. Granulite facies metamorphism(Stage Ⅰ) with P-T conditions of 9.8–10.4 kbar at 895–920°C was recorded by the porphyroblastic garnet core; HP granulite facies metamorphism(Stage Ⅱ) shows P-T conditions of 13.2–13.5 kbar at 845–860°C, based on the increasing grossular and decreasing pyrope contents of garnet rims. The Yushugou HP felsic granulites have recorded an anticlockwise P-T path, characterized by the temperature decreasing and pressure increasing simultaneously. The LA-ⅠCP-MS isotopic investigations on zircons from the felsic granulite show that the protolith ages of the granlulites are ~430 Ma, with two age groups of ~390 Ma and 340–350 Ma from the metamorphic rims of zircon, indicating the Stage Ⅰ and Ⅱ metamorphic events, respectively. A tectonic model was proposed to interpret the processes. The investigated felsic granulite was derived from deep rooted hanging wall, with Stage Ⅰ granulite facies metamorphism of ~390 Ma, which may be related to the Devonian arc magmatic intrusion; Stage Ⅱ HP granulite facies metamorphism(340–350 Ma) may due to the involvement of being captured into the subducting slab and experienced the high pressure metamorphism. 相似文献
328.
329.
Lu Xing 《云南地理环境研究》1999,(Z1)
1 Traitsofnon-profitorganizationsThethirdsectororthenon-profitorganization,togetherwithitssocialrolesindi-catesanewstageofsocialdevelopmentaswellasare-allocationofrolestodifferentor-ganizations,whichdrawsadividing-linebetweenthegovernmentandtheenterp… 相似文献
330.
Tertiary Sea Level Changes and Sequence Stratigraphic Framework in East China Sea Shelf Basin 总被引:1,自引:0,他引:1
TheEastChinaSeashelfbasinissituatedonthewestmarginofPacificplate(Fig.1)andisalargehydrocarbon-bearingsedimentarybasinfiledmai... 相似文献