检索结果-南通市图书馆

Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3, Xu Guanjun1,4. Zhu Cuishan2,3, Xiao Tingrong4. Zhang Min2,3 and Zhang Bin1,4.1. Key laboratory of Petroleum Geochemistry, china National Petroleum Corporation, Beijing 100083, china 2. Geochemistry Department of Yangtze University, Jingzhou 4.4.23, china 3. Key laboratory of Exploration Technologies for Oil and Gas Resources, ministry of education, Yangtze University, Jingzhou 4.4.23, china 4. Petroleum geology Central laboratory, Research Institute of Petroleum Exploration and Development, Petrochina, Beijing 100083, china) Key laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry Department Yangtze University Jingzhou 434023 China Key laboratory of Exploration Technologies for Oil and Gas Resources Yangtze University Jingzhou 434023 China Petroleum geology Central laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

Evolutionary cryptography theory based generating method for a secure Koblitz elliptic curve and its improvement by a hidden Markov models

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2012年第4期55卷 911-920页

作者： WANG Chao 1,ZHANG HuanGuo 2,3 & LIU LiLi 4.1 Key Lab of Specialty Fiber Optics and Optical Access Network,ministry of education,Shanghai University,Shanghai 200072,china 2 Computer School of wuhan University,wuhan 4.0072,china 3 Key laboratory of Aerospace Information Security and Trusted Computing ministry of education,wuhan 4.0072,china 4.Huawei Technologies CO.LTD.,Shanghai 201206,china Key Lab of Specialty Fiber Optics and Optical Access Network Ministry of Education Shanghai University Shanghai China Computer School of wuhan University Wuhan China Key laboratory of Aerospace Information Security and Trusted Computing ministry of education Wuhan China Huawei Technologies CO. LTD. Shanghai China

Considering potential attacks from cloud-computing and quantum-computing,it is becoming nec-essary to provide higher security elliptic *** hidden Markov models are introduced for designing the trace-vector computation algorithm to accelerate the search for elliptic curve (EC) *** present a new algorithm for secure Koblitz EC generation based on evolutionary cryptography *** algorithm is tested by selecting a secure Koblitz EC over the field F(2 2000),with experiments showing that both the base field and base point of the secure curve generated exceed the parameter range for Koblitz curves recommended by *** base fields generated go beyond 1900 bits,which is higher than the 571 bits recommended by *** also find new secure curves in the range F(2 163)-F(2 571) recommended by *** perform a detailed security analysis of those secure curves,showing that those we propose satisfy the same security criteria as NIST.

关键词： secure EC selection evolutionary cryptography theory ant colony algorithm Koblitz EC HMM

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2 & GAO Bangfei1,2 1. State Key laboratory of Geological Processes and Mineral Resources, china University of Geosciences, Beijing 100083, china 2. Key laboratory of Lithosphere Tectonics and Lithoprobing Technology of {4. of education, china University of Geo- sciences, Beijing 100083, china 3. Faculty of Earth Sciences, china University of Geosciences, wuhan 4.0074. china 4. School of Mathematics and Information Science, Guangzhou University, Guangzhou 5104.5, china State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Key laboratory of Lithosphere Tectonics and Lithoprobing Technology of ministry of education China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China School of Mathematics and Information Science Guangzhou University Guangzhou China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

GRACE detection of the medium-to far-field coseismic gravity changes caused by the 2004.Mw9.3 Sumatra-Andaman earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Science 2012年第3期25卷 235-240页

作者： Jin Li1,2,3 and Wenbin Shen1,3,4. 1 Department of Geophysics, School of Geodesy and Geomatics, wuhan University, wuhan 4.0079, china 2 Key laboratory of Geodynamic Geodesy of Chinese Academy, wuhan 4.0077, china 3 Key laboratory of Geospace Environment and Geodesy (ministry of education), wuhan University, wuhan 4.0079, china 4.State Key laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, wuhan 4.0079, china Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan China Key laboratory of Geodynamic Geodesy of Chinese Academy Wuhan China Key laboratory of Geospace Environment and Geodesy (ministry of education) Wuhan University Wuhan China State Key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan China

Large earthquakes cause observable changes in the Earth’s gravity field, which have been detected by the Gravity Recovery and Climate Experiment (GRACE). Since most previous studies focus on the detection of near-field gravity effects, this study provides the results from the medium- to far-field gravity changes caused by the 2004.Sumatra-Andaman earthquake that are recorded within GRACE monthly solutions. Utilizing a spherical-earth dislocation model we documented that large-scale signals predominate in the global field of the coseismic gravity changes caused by the earthquake. After removing the near-field effects, the coseismic gravity changes show a negative anomaly feature with an average magnitude of -0.18×10-8 m·s-2 in the region ranging ～4.° from the epicenter, which is considered as the 'medium ffield' in this study. From the GRACE data released by Center for Space Research from August 2002 to December 2008, we retrieved the large-scale gravity changes smoothed with 3 000 km Gaussian ffilter. The results show that the coseismic gravity changes detected by GRACE in the medium field have an average of (-0.20±0.06)×10-8 m·s-2, which agrees with the model prediction. The detection confirms that GRACE is sensitive to large-scale medium-field coseismic gravitational effects of mega earthquakes, and also validates the spherical-earth dislocation model in the medium field from the perspective of satellite gravimetry.

关键词： GRACE medium-to far-field coseismic gravity change 2004.Sumatra-Andaman earthquake spherical-Earth dislocation model

Holocene climate variation denoted by Barkol Lake sediments in northeastern Xinjiang and its possible linkage to the high and low latitude climates

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2011年第4期54卷 603-614页

作者： XUE JiBin & ZHONG Wei 1 School of Geography,South china Normal University,Guangzhou 510631,china 2 Key laboratory of Oasis Ecology(ministry of {4.) ,Xinjiang University,Urumqi 83004.,china 3 Key laboratory of Western china's environmental Systems(ministry of {4.) ,Lanzhou University,Lanzhou 730000,china School of Geography South China Normal University Guangzhou China Key laboratory of Oasis Ecology (ministry of education) Xinjiang University Urumqi China Key laboratory of Western china’s environmental Systems (ministry of {4.) Lanzhou University Lanzhou China

The climate over the closed inland Barkol Lake,which is located in northeastern Xinjiang Uygur Autonomous Region,is significantly influenced by westerly winds *** improve our understanding of past climate processes in westerly wind influenced regions in northwestern china,a 250-cm sediment section was retrieved from this *** taking the carbon reservoir effect into consideration,the chronological sequence of this section was reconstructed based on seven conventional radiocarbon dates of bulk samples,and the bottom age of this section was determined to be about 94.0 cal a ***-proxy datasets,includingδ18O car,δ13C car of authigenic carbonate,and total organic carbon were examined using wavelet analysis and singular spectrum analysis *** show that the Holocene in the Barkol Lake region can be divided into four stages:(1) a cold and dry early stage before～8000 cal a BP;(2) a moderately warm and wet middle stage between～8000 and 6000 cal a BP;(3) a warm and dry stage,along with a cooling-wetting tendency from 6000 to 2700 cal a BP;and(4. a fluctuating cooling and wet stage between 2700-800 cal a BP,and a drier stage since 800 cal a *** general trend of Holocene climatic changes revealed by Barkol Lake sediments was in agreement with that of adjacent *** infer that climatic changes during the Holocene in the Barkol Lake region were influenced not only by high latitudes,especially the North Atlantic region climate,but also tropical low-latitude processes,such as the El Nio/La Nia-Southern *** study demonstrates that the enhanced activities of ENSO may have played an important role in climatic changes in northeastern Xinjiang during the *** results also suggest that climatic patterns may be temporally different in the northern Xinjiang area in response to the changing predominant control of either the Westerly or the Asian summer monsoon,depending on the contrast of their relative strengths.

关键词： Barkol Lake Holocene climate change tropical processes northern high-latitude climate

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4.1. Faculty of Earth Science and State Key laboratory of Geological Processes and Mineral Resources, china University of Geosciences, wuhan 4.0074. china 2. Institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 4.4.03, china 3. Department of Computer Science, South-Central University for Nationalities, wuhan 4.0074. china 4. laboratory of Marine geology, Tongji University, Shanghai 200092, china china University of Geosciences Henan Polytechnic University South-Central University for Nationalities Tongji University

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

Microwave thermal remediation of crude oil contaminated soil enhanced by carbon fiber

在线全文

学校读者我要写书评

暂无评论

Journal of environmental Sciences 2009年第9期21卷 1290-1295页

作者： LI Dawei,ZHANG Yaobin,QUAN Xie,ZHAO Yazhi Key laboratory of Industrial Ecology and environmental Engineering,ministry of education of {4.,School of environmental and Biological Science and Technology,Dalian University of Technology,Dalian 116024.{4. Key laboratory of Industrial Ecology and environmental Engineering Ministry of Education of China School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024 China

Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber （CF） was explored. The contaminated soil was treated with 2.4. GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700℃ within 4.min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

关键词： microwave heating crude oil remediation carbon fiber

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4.1. State Key laboratory of Continental Dynamics, Department of geology, Northwest University, Xi`an 710069, china 2. State Key laboratory of Geological Processes and Mineral Resources, china University of Geosciences, wuhan 4.0074. china 3. Shenyang Institute of geology and Mineral Resources, Shenyang 110032, china 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., china State Key laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Shenyang Institute of geology and Mineral Resources Shenyang China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.31 wt%, Al_2O_3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-1323 μg/g) and Sr/Y(32-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(14.)Nd/^(14.)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

A Binder of Phosphogypsum-Ground Granulated Blast Furnace Slag-Ordinary Portland Cement

在线全文

学校读者我要写书评

暂无评论

Journal of wuhan University of Technology(Materials Science) 2011年第3期26卷 548-551页

作者：黄赟 Key laboratory of Silicate Materials Science and Engineering Ministry of EducationWuhan University of Technology

A new hydraulic cementitious binder was developed by mainly utilizing industrial byproducts phosphogypsum（PG）and ground granulated blast furnace slag（GGBFS）with small addition of ordinary portland cement（OPC）.The hydration process and microstructure were studied by X-ray diffraction（XRD） and scanning electronic microscopy（SEM）.OPC hydrated first at early age to form primarily C-S-H gel,ettringite and calcium hydroxide（CH）.GGBFS activated by CH and sulfate ions hydrated continuously at later age,producing more and more hydration products,C-S-H gel and *** the paste developed a denser microstructure and its strength *** 28 d compressive strength of the mixture of 50%PG,4.% GGBFS and 4.OPC exceeded 4. *** setting time was faster and 3 d and 7 d strength were higher when the proportion of OPC *** the 28 d strength decreased when OPC exceeded 4.due to large amount of ettringite formed at late hydration age which damaged the microstructure.

关键词： phosphogypsum ground granulated blast furnace slag hydraulic cementitious binder