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A possible Younger Dryas-type event during Asian monsoonal Termination 3

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Science China Earth Sciences 2006年第9期49卷 982-990页

作者： CHEN Shitao1, WANG Yongjin1, KONG Xinggong1, LIU Dianbing1, CHENG Hai2 & R.L. Edwards2 1. College of Geography Science, Nanjing Normal University, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210097, China 2. Department of Geology and Geophysics, University of Minnesota, Minneapolis MN55455, USA College of Geography Science Nanjing Normal University Jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing China Department of Geology and Geophysics University of Minnesota Minneapolis USA

Seven U-Th dates, 560 δ 18O data and microscopic sequences were measured for sta- lagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the de- cadal-resolution stalagmite δ 18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ 18O records from Nanjing, Jiangsu Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 30-year-resolution stalagmite δ 18O record from Yongxing Cave (1400 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3 at about 245±5 kaBP. Based on 3 U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3 from the Yongxing δ 18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ 18O record, generally agrees with the pattern of the YD event well-expressed in the Chi- nese stalagmite δ 18O records. This YD-type event is characterized by a large decrease in δ 18O value as much as 2.30‰, more than half of the δ 18O excursion between glacial/interglacial periods, and lasts 1371±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74±4 a. Our data corroborate the view that the re- peated occurrence of YD-type event was not an “accident”, possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.

关键词： stalagmite, Termination 3, Asian monsoon, YD-type event, Shennongjia, Hubei Province.

Electrochemical Reduction Characteristics of α-Nitronaphthalene inSulfuric Acid Solution

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Chinese Chemical Letters 1999年第11期10卷 945-948页

作者： Chun An MA Wen km ZHANG Yong Ping GAN Hui HUANG Mei Chao LI Shao Ping TONG(Department of Applied Chemistry, Zhejiang Universily of Technology, Hangzhou 310014) Department of Applied Chemistry Zhejiang University of Technology Hangzhou 310014 China

The'electrochemical reduction characteristics of α-nitronaphthalene in sulfuric acidsolution were first reported in this paper. The results showed that the 1-amino-5-naphthol can beprepared by electrodeduction from α-nitronaphthalene and reduction peak corresponding to thereaction of α-nitronaphthalene to 1-amino-3-naphthol was in the range of -0.40~0.60V(vs, D.H.E )on the amalgamated copper cathode in the presence of SnCl2 additives. The mechanism of α-nitronaphthalene electroreduction to 1-amino-5-naphthol was also investigated, the overallelectroreduction reaction was composed of two intermediate steps and two intermediate productsexisted in solution. The electrochemical reduction mechanism was similar to that of nitrobenzeneto para-aminophenol.

关键词： Electrochemical reduction α-nitronaphthalene 1-amino-5-naphthol.

DEEP SEISMIC SOUNDING EVIDENCE FOR TECTONIC INTERACTION BETWEEN TARIM AND WEST KUNLUN MT

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地学前缘 2000年第S1期7卷 221-222页

作者： Li Qiusheng 1,Lu Deyuan 1,Gao Rui 1,Li Jingwei 2,Fan Jingyi 2,Zhang Zhiying 2,Liu wen 2 (1 Lithosphere Research Center, Chinese Academy of Geological Sciences, Beijing 100037,China 2 562 institute, Chinese Academy of Geological Sciences, Hebei

The Tarim basin, located in the northern margin of Tibet, plays a key role in comprehending Tibetan plateau rapid uplift process. Focuses have been on the contribution of basin block to create high mountain (e.g.,Chen and Molnar,1977, Molnar et al.,1993, Ph. Matte, Tapponnier et al.,1996) since 1970. The models, which mainly depend on result of geological survey and other geophysical observation in the region excepted Deep Seismic Sounding, remained unsure because of blank(or absence ) of DSS data until our experiment was performed. How Tarim and west Kunlun to contact in depth ? What different is in crust structure between Tarim and west Kunlun Mt.? This is what we will reply to in our *** finished the program in 1997. A total of 120 set seismograms (with 3\|component sensors) and 18000kg (AT and TNT) dynamos were used for the DSS field project. 6 shot in Tarim basin and 1 shot in west Kunlun Mt. (Quanshuigou) had been shoot successfully. One shot (Pishan shot) is used as fan\|shape observation (offset is from 150km to 220km) in 6 shots located in Tarim basin. The survey line is along Hotan river across the Tarim basin from the north to the south. In particular, we carried 20 set seismic recorders to Kunlun Mt. to make a short line about 60 km as the southern tendency of our line. The seismic recorders were placed in an interval of 3km from one stations to the next and covered a distance of more than 300km. The stations have to be moved their location per 2\|shotting to form a meeting system or a tracing system (layout). Fig.1 showed our survey line and location of shot as well as recorder stations. Finally we gained 625 cassettes with original seismic record (include cassettes of shooting time recorder et al.). After data process total 1147 quite high\|quality three\|component digital records have been used to analyze. Here, only results of analyzing P wave data is given.

关键词： seismic evidence tectonic interaction Tarim West Kunlun Mt.

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脂蛋白对疏水性药物生物活性和配置的影响

国际药学研究杂志 2008年第5期35卷 392-395页

作者：黄世杰 Wasan km Brocks DR lee SD 军事医学科学院毒物药物研究所北京100850

与许多传统药物的高水溶性不同,新候选药物常为高脂溶性化合物。血液的水性环境是疏水性药物处置的不良热力学环境。然而,药物与循环中脂蛋白结合可以克服此种困难。阐明这些机制,即药物与脂蛋白结合及脂蛋白包裹的药物在血液和组织中... 详细信息

与许多传统药物的高水溶性不同,新候选药物常为高脂溶性化合物。血液的水性环境是疏水性药物处置的不良热力学环境。然而,药物与循环中脂蛋白结合可以克服此种困难。阐明这些机制,即药物与脂蛋白结合及脂蛋白包裹的药物在血液和组织中的分配,有利于洞察控制这些化合物药理活性和潜在毒性的因素。本文讨论疏水性药物和脂蛋白相互作用对各种疏水性化合物药代动力学性质、代谢、组织分布及生物活性的影响,扼要指出如何使用这些信息来发现和开发药物。

关键词：疏水性药物脂蛋白药代动力学

MASS ACCUMULATION IN THE CENOZOIC HOH XIL BASIN,NORTHERN TIBET

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地学前缘 2000年第S1期7卷 161-162页

作者： Liu Zhifei 1,2 ,Wang Chengshan 2,Yi Haisheng\+2[WT5,5”BX](1 Laboratory of Marine Geology,Tongji University,Shanghai 200092,China 2.Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China)

Sedimentary basins are where the products or erosion of the related reliefs *** sedimentary records preserved in the basins offer the possibility of quantifying the paleotopography z(x,y,t) at each point( x,y )of a given region at any time t in the past by using methods of mass balanced reconstruction(Hay et al.,1989,Métivier and Gaudemer,1997),The importance of paleotopography is on that atmospheric circulation models and the ocean circulation models which depend on them require knowledge of the topography of the land as an important input boundary condition which strongly affects the model output(Barron and Washington,1984,Ruddiman et al.,1997).Thus,a first step towards establishing paleoelevations is to reconstitute the history of sedimentary basins in terms of mass accumulation(Hay et al.,1989).This work reconstructs the space\|time depositional history and estimates the mass stored in the Hoh Xil basin,northern *** Hoh Xil basin,with an area of 101000km\+2 and an average elevation of over 5000m,is the largest Cenozoic sedimentary basin in the hinterland of the Tibetan *** the Early Eocene to the Early Miocene,a sediment pile of approximately 5 4km thick of fluvial mudstone,sandstone,and conglomerate and 0 3km thick of limestone was formed in the basin (Liu and Wang,2000;Liu et al.,2000).the mass estimate is derived from 21 measured field cross\|sections,with total thickness of 13479 *** results show that the Hoh Xil basin has undergone 7 stages of evolution from the Early Eocene to the Early Oligocene,with a period of no sedimentation during the Late *** Fenghuoshan Group was formed from the first four stages as 56 0～52 0,52 0～46 7,46 7～39 7,and 39 7～33 2Ma ago,with the depocenter moving eastward and *** Yaxicuo Group was formed from the two next stages as 33 2～32 2 and 33 2～30 2Ma *** Wudaoliang Group spread the entire basin during the last stage of ca.23 0～16 0Ma ago,with its depocenter in the northern part

关键词： mass accumulation Cenozoic Hoh Xil basin Tibet

Field Trial of 40 Gbit/s ETDM Prototype System over 219 km of Installed Single Mode Fiber

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光学学报 2003年第S1期23卷 659-660页

作者： Sang Soo lee Hyun Woo Cho Sang Kyu Lim Ki Ho Han Jin Soo Han Moo Jung Chu Je Soo Ko Kyeong-Mo Yoon Yong-Gi lee Optical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Communication Department Electronics and Telecommunications Research Institute Deajeon KoreaOptical Transmission Research Team Technical Laboratory KT Deajeon KoreaOptical Transmission Research Team Technical Laboratory KT Deajeon Korea

Transmission of 40Gbit/s NRZ signal was successfully demonstrated over 219km of installed SMF in KT's Daejeon area network. After transmission, the measured power penalty was 0.5dB for all the tributary channels.

关键词： of ET be over Field Trial of 40 Gbit/s ETDM Prototype System over 219 km of Installed Single Mode Fiber

A Remote Sensing-based Analysis on the Impact of Wenchuan Earthquake on the Core Value of World Nature Heritage Sichuan Giant Panda Sanctuary

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Journal of Mountain Science 2011年第3期8卷 458-465页

作者： YU Hu ZHAO Yongtao MA Yuewei SUN Yulian ZHANG Hu YANG Shihong LUO Yong Institute of Mountain Hazards and Environment ChineseAcademy of Sciences No. 9. Section 4. South Renmin Road China Graduate University of Chinese Academy of Sciences Beijing 100049 China Sichuan World Heritage Administrative Office

In this study,we used remotely sensed data,GIS modeling,and statistical methods to evaluate the damage caused by the Wenchuan Earthquake (May 12,2008) to the giant panda (Ailuropoda melanoleuca) habitat in the World Nature Heritage Sichuan Giant Panda Sanctuary (WHSGPS) in China.A landscape ecological analysis found increases of landscape heterogeneity,complexity,and fragmentation in the giant panda habitat after the earthquake.A terrain analysis found that slope and elevation are directly associated with the distribution of the damaged *** slope and elevation increase,the size of the damaged area keeps increase until to a peak,and then starts to *** total area of the damaged vegetation in our study area is 114.26 km 2,accounting for 3.78% of the study area;30.46% of that 114.26 km 2 is located in the Core Zone of *** are 18.57km 2 of the damaged vegetation located in the identified suitable giant panda habitat,accounting for 1.75% of the total area of suitable giant panda habitats in the study *** on these findings,we conclude that the Wenchuan Earthquake does not have significant impact on the WHSGPS as a whole.

关键词： World Nature Heritage Giant Panda Sanetuaries Suitable giant panda habitat Model Wenehuan Earthquake Landscape pattern GIS RS

A differentiable sphere theorem with positive Ricci curvature and reverse volume pinching

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Science China Mathematics 2011年第3期54卷 603-610页

作者： WANG PeiHe1 & WEN YuLiang2 1School of Mathematical Sciences, Qufu Normal University, Qufu 273165, China 2Department of Mathematics, East China Normal University, Shanghai 200241, China School of Mathematical Sciences Qufu Normal University Department of Mathematics East China Normal University

Let Mn be a compact, simply connected n (≥3)-dimensional Riemannian manifold without bound-ary and Sn be the unit sphere Euclidean space Rn+1. We derive a differentiable sphere theorem whenever themanifold concerned satisfies that the sectional curvature km is not larger than 1, while Ric(M)≥n+2 4 and the volume V (M) is not larger than (1 + η)V (Sn) for some positive number η depending only on n.

关键词： k-th Ricci curvature Hausdorff convergence differentiable sphere theorem harmonic coordinate harmonic radius

MAGNETOSTRATIGRAPHIC DATING:IMPLICATIONS FOR TERTIARY EVOLUTION OF THE HOH XIL BASIN, NORTHERN TIBET

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地学前缘 2000年第S1期7卷 157-159页

作者： Liu Zhifei 1,2 , Wang Chengshan 2, Zhao Xixi 3, Liu Shun 2 ,Yi Haishen 2[WT5,5”BX](1 Laboratory of Marine Geology, Tongji University, Shanghai 200092, China, E\|mail:lzhifei@online. *** 2 Institute of Sedimentary Geology, Chengdu University

The Hoh Xil basin, with an area of 101000km\+2 and an average elevation of over 5000m, is a largest Tertiary sedimentary basin in the hinterland of the Tibetan plateau. It is situated in the western part of the Baya Har terrain (BT) and the northern part of the Qiangtang terrain (QT), and covers the Jinsha River Suture Zone (JRSZ), one of the five continental suture zones on the Tibetan plateau. Strong deformation and crustal shortening of about 40% at the Fenghuoshan area (Coward,et al.1990) or 42.8% at the Wudaoliang—Fenghuoshan area (Wang,et al.1999) happened at the northern Tibet before the Neogene. Therefore, sediments deposited the Hoh Xil basin may contain significant information of crustal shortening and early uplift of the Tibetan plateau. However, anterior researchers met a same painful problem to date the sedimentary sequences in the basin. By using a few fossils, they assessed doubt ages for main strata in the Hoh Xil basin, as the Paleogene / Eocene (Yi,et al.1990) or the Cretaceous (BGMRQ 1991; Zhang & Zheng 1994), since other datable materials like volcanic rocks are absent. Therefore, the precise stratigraphic dating becomes a precondition of more scientific research in the northern Tibet.

关键词： magnetostratigraphy basin evolution the Hoh Xil basin norther n Tibet