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Distribution and fractionation mechanism of stable carbon isotope of coalbed methane

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Science china Earth Sciences 2006年第12期49卷 1252-1258页

作者： QIN Shengfei1, TANG Xiuyi2, SONG Yan1 & WANG Hongyan3 1. research Institute of Petroleum Exploration and development, Petrochina, beijing 100083. china 2. Anhui Science and Technology College, Huainan 232000, china 3. Langfang Branch, research Institute of Petroleum Exploration and development, Petrochina, Langfang 065007, china 1. research Institute of Petroleum Exploration and development PetroChina Beijing 100083 China 2. Anhui Science and Technology College Huainan 232000 China 3. Langfang Branch Research Institute of Petroleum Exploration and Development PetroChina Langfang 065007 China

The stable carbon isotope values of coalbed methane range widely, and also are gener- ally lighter than that of gases in normal coal-formed gas fields with similar coal rank. There exists strong carbon isotope fractionation in coalbed methane and it makes the carbon isotope value lighter. The correlation between the carbon isotope value and Ro in coalbed methane is less obvious. The coaly source rock maturity cannot be judged by coalbed methane carbon isotope value. The carbon isotopes of coalbed methane become lighter in much different degree due to the hydrodynamics. The stronger the hydrodynamics is, the lighter the CBM carbon isotopic value becomes. Many previous investigations indicated that the desorption-diffusion effects make the carbon isotope value of coalbed methane lighter. However, the explanation has encountered many problems. The authors of this arti- cle suggest that the flowing groundwater dissolution to free methane in coal seams and the free methane exchange with absorbed one is the carbon isotope fractionation mechanism in coalbed methane. The flowing groundwater in coal can easily take more 13.H4 away from free gas and com- paratively leave more 12CH4. This will make 12CH4 density in free gas comparatively higher than that in absorbed gas. The remaining 12CH4 in free gas then exchanges with the adsorbed methane in coal matrix. Some absorbed 13.H4 can be replaced and become free gas. Some free 12CH4 can be ab- sorbed again into coal matrix and become absorbed gas. Part of the newly replaced 13.H4 in free gas will also be taken away by water, leaving preferentially more 12CH4. The remaining 12CH4 in free gas will exchange again with adsorbed methane in the coal matrix. These processes occur all the time. Through accumulative effect, the 12CH4 will be greatly concentrated in coal. Thus, the stable carbon isotope of coalbed methane becomes dramatically lighter. Through simulation experiment on wa- ter-dissolved methane, it had been proved that the f

关键词： coalbed methane,methane stable carbon isotope,fractionation mechanism,accumulative effect.

Present geotemperature and its suggestion to natural gas generation in Xujiaweizi fault-depression of the northern Songliao Basin

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Science china Earth Sciences 2008年第S1期51卷 207-220页

作者： ZHOU QingHua 1,2 ,FENG ZiHui 3 &MEN GuangTian 3 1 research Institute of Petroleum Exploration and development,Petrochina,beijing 100083.china 2 Geological Logging Subcompany of Daqing Oil Field Company Ltd.,Daqing 163411,china 3 research Institute of Petroleum Exploration and development of Daqing Oil field Company Ltd.,Daqing 163732,china Petrochina Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China Daqing Oil Field Co Ltd Geol Logging Subco Daqing 163411 Peoples R China Daqing Oil field Co Ltd Res Inst Petr Explorat & Dev Dacling 163732 Peoples R China

According to stastistic of present geotemperatures at the depths of 1000,2000,3000 and 4000 m,respectively in the Xujiaweizi fault-depression of the north Songliao Basin,the result indicates that Xujiaweizi fault-depression falls in the high geotemperature area,with the higher geothermal gradient in the depression layer than that in the fault-depression *** geothermal gradient decreases with the increasing of the *** thermal conductivity of rock greatly controls the geothermal *** main factors constraining the current geotemperature include thermal configuration of the earth's crust, deep faults,distribution and abundance of *** high geotemperature is in favour of generation of deep gas.

关键词： Xujiaweizi fault-depression geotemperature geothermal gradient thermal conductivity of rock deep layer natural gas

PETROLIFEROUS　PROVINCE　AND　RESOURCE　POTENTIAL　OF　THE　NORTHEAST　ASIA　THE　MOST　PROSPECTIVE　NEW──THE　MOST　PROSPECTIVE　NEW　PROVINCE　IN　ASIA

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石油勘探与开发 1994年第2期 110-118页

作者： Hu Jian-yi Xu Shu-bao Don Li-rong(research Institute of Petroleum Exploration and development, CNPC.beijing, china, 100083.

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ＰＥＴＲＯＬＩＦＥＲＯＵＳＰＲＯＶＩＮＣＥＡＮＤＲＥＳＯＵＲＣＥＰＯＴＥＮＴＩＡＬＯＦＴＨＥＮＯＲＴＨＥＡＳＴＡＳＩＡＴＨＥＭＯＳＴＰＲＯＳＰＥＣＴＩＶＥＮＥＷ──ＴＨＥＭＯＳＴＰＲＯＳＰＥＣＴＩＶＥＮＥＷＰＲＯＶＩＮＣＥＩＮＡＳＩＡＨｕＪｉａｎ－ｙ...

关键词： petroliferous basin folded belt (Northeast Asia) (Siberian Plate) (Sino-Korean Plate)

Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,china 2 State Key Laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 4 State Key Laboratory of Information Security(Graduate University of Chinese Academy of Sciences) ,beijing 100049,china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 China 3. State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China 4. State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China 2. State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Urotensin Ⅱ accelerates cardiac fibrosis and hypertrophy of rats induced by isoproterenol

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Acta Pharmacologica Sinica 2007年第1期28卷 36-43页

作者： Yong-gang ZHANG~(2,5) Yu-guang LI~2 Bao-guo LIU~3 Rui-hong WEI~2 Dong-ming WANG~2 Xue-rui TAN~2 Ding-fang BU~4 Yong-zheng PANG~4 Chao-shu TANG~42 Department of Cardiovascular Diseases,First Affiliated Hospital,Shantou University Medical College,Shantou 515041,china 3 The Affiliated Hospital,Medical School of Hebei University of Engineering,Hebei 056029,china,4 Institute of Cardiovascular research,Peking University First Hospital,beijing 100034,china Department of Cardiovascular Diseases First Affiliated Hospital Shantou University Medical College Shantou China The Affiliated Hospital Medical School of Hebei University of Engineering Hebei China Institute of Cardiovascular research Peking University First Hospital Beijing China

Aim:To study whether urotensin II（UII）,a potent vasoconstrictive peptide,isinvolved in the development of cardiac hypertrophy and fibrogenesis of ratsinduced by isoproterenol（ISO）.Methods:Thirty male Wistar rats were randomlydivided into 3 *** 1 was the healthy control group,group 2 was the ISOgroup,and group 3 was the ISO+UII *** groups 2 and 3,ISO(5 mg-kg-1.d-1)wasgiven（sc）once daily for 7 *** 3 was also given UII in the first day [3 nmol/kg（5μg/kg）,iv],followed by sc（1.5 μg/kg）twice *** 1 received 0.9% *** receptor（UT）mRNA expression was determined by *** contents ofUII and angiotensin II（Ang II）were determined by *** vitro,the effects of UII on DNA/collagen synthesis of cardiac fibroblasts were deter-mined by [3H]thymidine/[3H]proline ***:The ratio of heartweight/body weight,plasma lactate dehydrogenase activity,myocardialmalondialdehyde and hydroxyproline concentration increased significantly in theISO group,as well as UT mRNA expression,plasma and cardiac UII and ventricu-lar Ang II,compared with the control group（Pdevelopment ofcardiac fibrosis and hypertrophy by synergistic effects with ISO.

关键词： cardiac remodeling cardiac fibrosis GPR14 receptor urotensin II collagen

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,china 2 State Key Laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 3 State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences),beijing 100049,china 4 State Key Laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Carbon isotope composition and its implications of Lower Cretaceous Aptian-Albian shallow water carbonates in the Cuoqin Basin, North Tibet

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Science china Earth Sciences 2004年第3期47卷 247-254页

作者： ZHU Jingquan1, LI Yongtie2, JIANG Maosheng1 & CHEN Daizhao1 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2. research Institute of Petroleum Exploration and development, CNPC, beijing 100083. china Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China CNPC Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China

The d 13. values of Lower Cretaceous Aptian-Albian platform-type carbonates in the Cuoqin Basin, North Tibet vary between 2.48 and 5.46. The mean value is 3.93. The values are not only provided with positive excursion, but also 1.17 higher than those of con-temporaneous pelagic carbonates which possess pretty high d 13. values. The origin is ap-proached. During the oceanic anoxic events, a great number of organisms were rapidly buried, causing the increase of the d 13. value of oceanic total dissolved carbon (TDC) and generally promoting the values of marine carbonates. After that, owing to the organisms undergoing dif-ferent isotopic fractionation in the paleo-ocean with stratified structure, d 13. values of shallow sea carbonate were obviously higher than those of pelagic carbonates.

关键词： shallow water carbonate, stable carbon isotope, paleooceanography, Aptian-Albian stage, Cuoqin Basin.

Carbon and Oxygen Stable Isotope Values and Microfossils at 41.4-4.5ka BP in Tai Co,Tibet,china,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1,2,*),LIU Junying~(1,3),MA Zhibang~(1,4),WANG Hailei~(1,2) and MA Nina~(1,2) 1 MLR Key Laboratory of Saline Lake Resources and Environment,Institute of Mineral Resources,CAGS, beijing 100037,china 2 research and development Center for Saline Lakes and Epithermal Deposits,Chinese Academy of Geological Sciences,beijing 100037,china 3 Institute of Geology,Chinese Academy of Geological Sciences,beijing 100037,china 4 Key Laboratory of Cenozoic Geology and Environment,Chinese Academy of Sciences,beijing 100029, china MLR Key Laboratory of Saline Lake Resources and Environment Institute of Mineral Resources CAGS Beijing 100037 China research and development Center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Cenozoic Geology and Environment Chinese Academy of Sciences Beijing 100029 China *Correspondence: Mianping ZHENG *Correspondence: Corresponding author. E-mail: zhengmp2010@***

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>10 cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 41.4 to 4.5 ka BP:at 41.4-26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-17.5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 17.5-16.0 ka BP,it was slightly cold-dry;at 16.0-11.8 ka BP,it was slightly warm-wet;at 11.8-10.4 ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 10.4 ka BP,the temperatures began to rise again;at 10.4-9.4 ka BP,it was slightly warm-wet;at 9.4-8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(41.4-4.5 ka BP) Tai Co Tibet

Future Trends of Deep Sea Bed Mining Technology

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 4-7页

作者： Yan Feng Haoran Li Wenming Zhang (Resources Engineering School, University of Science and Technology beijing, beijing 100083. china) Resources Engineering School University of Science and Technology Beijing Beijing 100083 China

The present status of deep sea bed mining technology for polymetallic nodules has been critically examined in light of its history of development the UNCLoS (the United Nation Convention on the Law of the Sea) regime and the current trends in *** critical technologies have been highlighted and the need for system integration underscored. The deep sea bed environment and the engineering challenge were presented and the necessary features of the deep sea bed mining system for commercial mining was analyzed. The key accomplishments, problems and future bends in research in the development of the mining system are also discussed. Finally, it points out that the technology gaps can be filled by the bine commercial mining is undertaken as a result of market conditions in its favor.

关键词： deep sea bed mining, UNCLoS TIS (Total Integrated System), polymetallic nodules mining system