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Palaeorunoff estimations achieved from palaeoclimatic information for the southwest part of the North China Plain: an attempt to apply a climatological approach to palaeohydrology

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Journal of Environmental Sciences 2000年第3期12卷 330-336页

作者： WANG Hong\|ya, XIE Qiang (department of Urban and Environmental Sciences, peking university,{2. 100871, China) 北京大学北京 1 0 0 871

Palaeoclimatic scenario projecting annual temperature and annual precipitation is firstly formalized with data available and speculations for the southwest part of the North China Plain (35— 37°N, 115—119°E) during the last 2.000 years. Then, with three regression equations relating annual runoff to annual precipitation and derived with data of modern hydrological and meteorological records, values of annual runoff are calculated in terms of the corresponding values of annual precipitation from this palaeoclimatic scenario for this region during this temporal interval. These results indicate that runoff is the most during 8000—3000 a B.P. and the least during 2.000—12.00 a B.P.; runoff occurring during 12.00—8000 a B.P. and during 3000—0 a B.P. is less than the one occurring during 8000—3000 a B.P. and more than the one occurring during 2.000—12.00 a B.P.; and the runoff occurring during 2.000—12.00 a B.P., 12.00—8000 a B.P., and 3000—0 a B.P. is respectively 43, 46 and 66 percent of the one occurring during 8000—3000 a B.P. Values of bankfull discharge for palaeochannels of the Yellow River flowing in this region during the same interval are calculated from available estimates of slope of stream bed of these palaeochannels with a regression equation relating bankfull discharge to slope of stream bed and ratios of bankfull discharge are further calculated from these values for different groups of palaeochannel formed during different time spans embraced in this interval. To conduct a cross check, these values and ratios of bankfull discharge are compared to the corresponding values and ratios of runoff occurring during roughly the same time spans. The same direction and similar relative magnitude of changes of the surface water occurring in this region during the last 2.000 years are indicated by these comparisons.

关键词： palaeorunoff the southwest part of the North China Plain palaeoclimate

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Flooding 1990s along the Yangtze River, has it concern of global warming?

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Journal of Geographical Sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1, ZHU Jin-hong2. WANG Shao-wu2.(1. Key Laboratory of Environmental Change and Natural Disaster, Institute of Resources Science, beijing Normal university, beijing 100875, China 2. department of Geophysics, peking university, beijing 100871, Key Laboratory of Environmental Change and Natural Disaster Institute of Resources Science Beijing Normal University Beijing China department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in China during the 1990s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1980s and the 1990s is much higher than that in the previous 3 decades. The means for 1990–1999 is +87.62.mm above normal, marked the 1990s the wettest decade since the 1950s. Six stations with a time span of 1880–1999 are selected to establish century-long rainfall series. This series also shows that the 1990s is the wettest decade during the last 12. years. In the wettest 12.years, four occurred in the 1990s (1991, 1996, 1998 and 1999). Both global and China’s temperature show there is a relative lower air temperature during the 1960–1970s, and a rapid warming in the 1980–1990s. Comparisons of rainfall between 1960–1979 and 1980–1999 show there are dramatic changes. In the cold period 1960–1979, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1980–1999, over 8.4 % to 18.2.% of summer rainfall occurs. Over the whole eastern China, the summer rainfall shows opposite spatial patterns from the 1960–1970s to 1980–1990s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1990s is the severest during the past 150 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 33.3 and 11.8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

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Analysis of Environmental and Socio-economic Determinants Affecting Population Longevity Level at County Level in China

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 36-41页

作者： Lu Jiehua , Wang Hongbo 1 2.& Pan Yi 1 1. Institute of Population Research, peking university, beijing 100871, China 2. {2. of Sociology, university of California at Los Angeles, Los Angeles, USA. Institute of Population Research Peking University Beijing 100871 China department of Sociology University of California at Los Angeles Los Angeles United States

Based on the current literature, this paper is mainly intended to test whether environmental factors and socio-economic factors will have direct effect on the longevity at county level in China in order to determine the major determinants affecting local longevity level. Using the multi-regression model, we find the result that factors such as temperature, climate, longitude, type of soils, as well as type of agricultural food production play a major role in shaping the longevity at county level, and that socio- economic factors like infant mortality and gross death rate also have some direct impact on longevity, but the degree of impact is not as strong as the above environmental factors.

关键词： longevity socio-economic factors environmental factors

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Inhibition of platelet aggregation by polyaspartoyl L-arginine and its mechanism

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Acta Pharmacologica Sinica 2004年第4期25卷 71-75页

作者： Yin-ye WANG, Zhi-yu TANG, Min DONG, Xiao-yan LIU, Shi-qi PENG2.department of Pharmacology, department of Medicinal Chemistry, 2.Schoolof Pharmaceutical Sciences,{2., beijing 100083, China department of Pharmacology Department of Medicinal Chemistry School of Pharmaceutical Sciences Peking University

AIM: To observe the oral anti-platelet efficacy and the potential action mechanism of polyaspartoyl L-arginine (PDR), a new L-arginine rich compound. METHODS: Platelet aggregation was conducted by Born’s method; bleeding time was determined using tail’s bleeding time in mice; platelet adhesion was carried out with glass bottle method; nitric oxide (NO) was tested with Griess’ method; and cAMP, thromboxane B2.(TXB2. and 6-keto-PGF1α were assessed with commercial kits. RESULTS: The inhibition by PDR (15-60 mg/kg ig or 10 mg/kg iv) of platelet aggregation induced by adenosine diphosphate (ADP), collagen or thrombin at 1 h after oral administration or at 2. min after iv injection for rats (P2.or 6-keto-PGF1α in plasma. CONCLUSION: PDR is a novel, oral effective platelet aggregation inhibitor and its action mechanism possibly related to increasing NO generation.

关键词： platelet aggregation bleeding time platelet adhesiveness polyaspartoyl L-arginine nitric oxide cyclic AMP Thromboxane B2 6-ketoprostaglandin F1 alpha

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The localization of 1-cohomology of transitive Lie algebroids

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Science China Mathematics 2006年第2期49卷 277-288页

作者： CHEN Zhuo & LIU Zhangju department of Mathematics, Capital Normal university,{2. 100037, China School of Mathematical Science, peking university,{2. 100871, China 1. department of Mathematics Capital Normal University Beijing 100037 China 2. School of Mathematical Science Peking University Beijing 100871 China

For a transitive Lie algebroid A on a connected manifold M and its representation on a vector bundle F, we define a morphism of cohomology groups rk: Hk(A,F) → Hk(Lx,Fx), called the localization map, where Lx is the adjoint algebra at x ∈ M. The main result in this paper is that if M is simply connected, or H (LX,FX) is trivial, then T is injective. This means that the Lie algebroid 1-cohomology is totally determined by the 1-cohomology of its adjoint Lie algebra in the above two cases.

关键词： transitive Lie algebroid representation cohomology localization.

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AutoProc: An automatic proactive replication scheme for P2. storage

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Science China(Information Sciences) 2011年第6期54卷 1151-1160页

作者： YANG Zhi & DAI YaFei Computer Science department, peking university,{2. 100871, China 1. Computer Science department Peking University Beijing 100871 China

Due to the prevalence of peer departures, P2. storage systems need to constantly generate replicas for high durability. However, few existing systems are able to select the right replication rate that balances replication cost and durability, e.g., minimizing replication cost without threatening the durability target. In this paper, we propose a method called AutoProc to automate the replication process in P2. storage systems. AutoProc employs two key techniques to enable cost-effective replication: correctly adapting replication rate with a reliability model, and replicating objects at the right order with a reliability indicator. Extensive simulations based on the real system failure trace show that AutoProc achieves the near-optimal performance.

关键词： P2. storage churn durability fault tolerance proactive replication resource usage

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A new enzymatic method for determination of E. coli

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Chinese Chemical Letters 1999年第10期10卷 849-850页

作者： Yun Xiang CI Tian Le LI(department of Chemistry, peking university.{2. 100871) beijing Univ Dept Chem Beijing 100871 Peoples R China

beta-Galactosidase, a kind of endoenzyme in E. coli cells. can be released by the pore-forming action of colicin El. and E. coli can be detected rapidly by enzymatic method.

关键词： E-coli colicin E1 enzymatic method

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Self-talk of Reflection Hologram During its construction

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Chinese Journal of Lasers 1996年第4期B5卷 334-340页

作者： LIU Dahe ZHOU Jing(department of physics,{2. Normal university,beijing100875, China) beijing Normal Univ Beijing China

Ｓｅｌｆ－ｔａｌｋｏｆＲｅｆｌｅｃｔｉｏｎＨｏｌｏｇｒａｍＤｕｒｉｎｇｉｔｓｃｏｎｓｔｒｕｃｔｉｏｎ￥ＬＩＵＤａｈｅ；ＺＨＯＵＪｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＢｅｉｊｉｎｇＮｏｒｍａｌＵｎｉｖｅｒｓ... 详细信息

Ｓｅｌｆ－ｔａｌｋｏｆＲｅｆｌｅｃｔｉｏｎＨｏｌｏｇｒａｍＤｕｒｉｎｇｉｔｓｃｏｎｓｔｒｕｃｔｉｏｎ￥ＬＩＵＤａｈｅ；ＺＨＯＵＪｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＢｅｉｊｉｎｇＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７５...

关键词： reflection hologram hologram grating self-talk

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Inclusive　Minimal　Surfacein　G2.n1

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北京大学学报(自然科学版) 1996年第3期 3-7页

作者： MO Miaohuan (department of Mathematics, peking university,{2., 100871)

刻划了从Ｒｉｅｍａｎｎ面到复Ｇｒａｓｓｍａｎｎ流形的具有拓扑度＞２ｎ（ｇ－１）或′阶有限的一切可兼极小浸入。

关键词：可兼极小浸入 Riemann面复Grassmann流形

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INVESTIGATION　ON　THE　WATER－SOLUBLE　YTTERBIUM　PORPHYRIN　PART　***，COMPOSITION　AND　STRUCTURE

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Chinese Chemical Letters 1995年第2期6卷 147-148页

作者： QianKun ZHUANO Xiao Xia GAO(department of Chemistry, peking university,{2., 100871) beijing Univ Dept Chem Beijing 100871 Peoples R China

Water-soluble ytterbium complex of tetra-p-sulfonatophenylporphyrin (H2.PPS)with the formulation Yb·TPPS·OH·2.im·3H2. (im=imidazole), stable in pH5 solution, has been synthesized and characterized by clemental analysis, IR and electronic absorption spectroscopy,Its structure is also proposed. The ytterbium atom exbibits a coordination number of seven with the ytterbium atom out of the prophyrin plane.

关键词： J

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