检索结果-南通市图书馆

Journal of Mountain Science 2008年第3期5卷 249-256页

作者： LU Xuyang CHENG Genwei XIAO Feipeng HUO Changfu Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate University of the chinese academy of sciences Beijing 100049 China

The process-oriented model Forest-DNDC describing biogeochemical cycling of C and N and GHGs （greenhouse gases） fluxes （CO2. NO and N2.） in forest ecosystems was applied to simulate carbon sequestration and GHGs emissions in Abies fabric forest of the Gongga Mountains at southeastern edge of the Tibetan Plateau. The results indicated that the simulated gross primary production （GPP） of Abies fabric forest was strongly affected by temperature. The annual total GPP was 2.,2.5.3 kg C ha^-1 yr^-1 for 2.05 and 2.,318.8 kg C ha^-1 yr^-1 for 2.06, respectively. The annual total net primary production （NPP） was 5,935.5 and 4,882.2.kg C ha^-1 yr^-1 for 2.05 and 2.06, and the annual total net ecosystem production （NEP） was 4,815.4 and 3,512.8 kg C ha^-1 yr^-1 for 2.05 and 2.06, respectively. The simulated seasonal variation in CO2.emissions generally followed the seasonal variations in temperature and precipitation. The annual total CO2.emissions were 3,109.0 and 4,82..0 kg C ha^-1 yr^-1 for 2.05 and 2.06, the simulated annual total N2. emissions from forest soil were 1.47 and 1.36 kg N ha^-1 yr^-1 for 2.05 and 2.06, and the annual total NO emissions were 0.09 and o.12.kg N ha^-1 yr^-1 for 2.05 and 2.06, respectively.

关键词： Carbon sequestration Forest-DNDC GHGs Abiesfabric forest Gongga Mountains

Use-wear evidence confirms the earliest hafted chipped-stone adzes of Upper Palaeolithic in northern china

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2010年第3期55卷 268-275页

作者： ZHANG XiaoLing1,2.3, SHEN Chen1,2.4 GAO Xing1,2.CHEN FuYou1,2.& WANG ChunXue1,2.3 1Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, Beijing 100044, china 2.aboratory of Human Evolution and Archaeometry, chinese academy of sciences, Beijing 100044, china 3graduate University of chinese academy of sciences, Beijing 100049, china 4The Royal Ontario Museum, Toronto M5S 2.6, Canada Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing 100044 China graduate University of chinese academy of sciences Beijing 100049 China Royal Ontario Museum Toronto M5S 2C6 Canada

Chipped-stone "adze-shaped objects" (ASOs) were identified from a few Upper Palaeolithic sites in northern china. Its morpho- logical form resembles to ground-stone type-specific adze, but the function of the ASO has never been assessed. The objective of this study is to investigate the use function of this particular tool type recovered from the Hutouliang site in the Nihewan Basin of northern china. In this study, the lithic use-wear analysis is applied to examining microscopically edge-damages and sur- face-rounding of the tools in order to assess how they were employed. The result suggests that the ASO might have been used as woodworking tools with a hafted shaft, providing evidence for the appearance of the earliest hafted chipped-stone adzes prior to 10000 years ago in northern china. This study also demonstrates that the use-wear technique is an innovated and effective analytic appraoch to the study of stone tool functions that has been conventionally treated by typo-technological analyses. Stone tool use-patterns revealed by use-wear evidence would shed new insights on prehistoric adaptive strategies of modern human in northern china.

关键词：旧石器时代晚期中国北方磨损证据石材加工工具木工工具中国网站技术分析

Application of the phylogenetic analysis in mitochondrial disease study

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2008年第18期53卷 2733-2738页

作者： WANG ChengYe1,2.3, KONG QingPeng1,2.& ZHANG YaPing1,2. 1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, chinese academy of sciences, Kunming 6502.3, china 2.Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, china 3 graduate University of chinese academy of sciences, Beijing 100049, china chinese Acad Sci Kunming Inst Zool State Key Lab Genet Resources and Evolut Kunming 650223 Peoples R China.

Mitochondrial disease currently received an increasing concern. However, the case-control design commonly adopted in this field is vulnerable to genetic background, population stratification and poor data quality. Although the phylogenetic analysis could help solve part of these problems, it has not received adequate attention. This paper is a review of this method as well as its application in mito- chondrial disease study.

关键词：线粒体疾病分析单元型种群分布

Investigation into the rotational bands of ^(185)Pt with the particle-rotor model

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 114-118页

作者： LI GuangShun1,2. ZHOU XiaoHong1,2. ZHANG ShuangQuan3, ZHANG YuHu1 & MENG Jie3 1 Institute of Modern Physics, chinese academy of sciences, Lanzhou 730000, china 2.{2. University of chinese academy of sciences, Beijing 100049, china 3 school of Physics and SK Laboratory of Nuclear Physics & Technology, Peking University, Beijing 100871, china 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. graduate University of chinese academy of sciences Beijing 100049 China 3. school of Physics and SK Laboratory of Nuclear Physics & Technology Peking University Beijing 100871 China

Theoretical calculations have been performed for the ν9/2.[62.](i13/2. and ν7/2.[503](f7/2. bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2.[62.](i13/2. component, while the negative-parity band shows strong mixing of ν7/2.[503](f7/2. and ν9/2.[505](h9/2. configurations.

关键词： High-spin states particle-rotor model signature splitting configuration mixing

On designated-weight Boolean functions with highest algebraic immunity

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第11期53卷 2847-2854页

作者： LIU MeiCheng1,3, DU YuSong2. PEI DingYi2.& LIN DongDai1 1The State Key Laboratory of Information Security, Institute of Software of chinese academy of sciences, Beijing 100190, china 2.ollege of Mathematics and Information {2., Guangzhou University, Guangzhou 510006, china 3graduate University of chinese academy of sciences, Beijing 100049, china 1. The State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. College of Mathematics and Information Sciences Guangzhou University Guangzhou 510006 China

Algebraic immunity has been considered as one of cryptographically significant properties for Boolean functions. In this paper, we study ∑d-1 i=0 (ni)-weight Boolean functions with algebraic immunity achiev-ing the minimum of d and n - d + 1, which is highest for the functions. We present a simpler sufficient and necessary condition for these functions to achieve highest algebraic immunity. In addition, we prove that their algebraic degrees are not less than the maximum of d and n - d + 1, and for d = n1 +2.their nonlinearities equalthe minimum of ∑d-1 i=0 (ni) and ∑ d-1 i=0 (ni). Lastly, we identify two classes of such functions, one having algebraic degree of n or n-1.

关键词： cryptography Boolean function algebraic immunity algebraic degree nonlinearity

Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2010年第3期7卷 234-245页

作者： SU Fenghuan Key Laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China graduate University of the chinese academy of sciences Beijing China

The Wenchuan earthquake on May 12.2.08 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS40 aerial imagery,SPOT5 imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3% of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor

A cyclic behavior of CME accelerations for accelerating and decelerating events

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2009年第10期9卷 1165-1172页

作者： Peng-Xin Gao Ke-Jun Li National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate University of chinese academy of sciences Beijing 100049 China

We investigate the cyclic evolutionary behavior of CME accelerations for accelerating and decelerating CME events in cycle 2. from 1997 January to 2.07 December. It is found that the absolute values of semiannual mean accelerations of both accelerating and decelerating CME events roughly wax and wane in a cycle, delaying the sunspot cycle in time phase. We also investigate the semiannual number of CMEs with positive and neg- ative acceleration and find that there are more decelerating CME events than accelerating CME events during the maximum period of a cycle （about three years）, but there are more accelerating CME events than decelerating CME events during the rest of the time interval of the cycle. Our results seem to suggest that the different driving mechanisms may be acting accelerate and decelerate CME events; for accelerating CME events, the propelling force （Fp） statistically seems to play a significant role in pushing CMEs outward; for decelerating CME events, the drag （Fd） statistically seems to play a more effective role in determining CME kinematic evolution in the outer corona. During the maximum period of a cycle, because of the V^2.dependence, Fd is generally stronger; because of the magnetic field dependence, Fp is also generally stronger. Thus, the absolute values of both the negative and positive accelerations are generally larger during that time. Because of the V^2.dependence, Fd may be more effective during the maximum period of a cycle. Hence, there are more decelerating CME events than accelerating CME events during that time. During the minimum time interval of a cycle, CMEs have relatively small speeds, and Fp may be more effective. Therefore, there are more accelerating CME events than decelerating CME events during that time.

关键词： Sun corona -- Sun coronal mass ejections (CMEs)

Influence of Fly Ash and Silica Fume on Water-resistant Property of Magnesium Oxychloride 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) 2010年第4期25卷 721-724页

作者：李成栋于红发 Qinghai Institute of Salt Lakes Chinese Academy of Sciences graduate school of{2. Nanjing University of Aeronautics and Astronautics Department of Civil Engineering

By incorporation of fly ash or silica fume into magnesium oxychloride （MOC） cement, a high water resistance material can be formed for successful industrial applications. The influences of fly ash and silica fume on water-resistant property were investigated by SEM and EDS. It is found that the incorporation of fly ash or silica fume can improve the water-resistance of the MOC. The improvement of the water resistance of the MOC incorporated with fly ash or silica fume may be attributed to the alumino-silicate 5·1·8 gel or silicate 5·1·8 gel.

关键词： magnesium oxychloride cement fly ash silica fume water resistance

Evolutionary pattern of the regulatory network for flower development:Insights gained from a comparison of two Arabidopsis species

在线全文

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2011年第6期49卷 528-538页

作者： 1,2.Yang LIU 1,2.hun-Ce GUO 1Gui-Xia XU 1Hong-Yan SHAN 1Hong-Zhi KONG 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of {2.,Beijing 100093,china) 2.graduate University of chinese academy of sciences,Beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate University of chinese academy of sciences Beijing 100049 China) *Correspondence: Hong-Zhi KONG *Correspondence: E-mail: hzkong@*** Tel.: 86-10-62.36489 Fax: 86-10-62.90843.

Previous studies on Arabidopsis thaliana and other model plants have indicated that the development of a flower is controlled by a regulatory network composed of genes and the interactions among *** on the evolution of this network will therefore help understand the genetic basis that underlies flower *** this study,by reviewing the most recent published work,we added 31 genes into the previously proposed regulatory network for flower ***,the number of genes reached *** then compared the composition,structure,and evolutionary rate of these genes between *** and one of its allies,*** found that two genes(FLC and MAF2.show 1:2.and 2.2.relationships between the two species,suggesting that they have experienced independent,post-speciation *** the remaining 58 genes,35(60.3%)have diverged in exon-intron structure and,consequently,code for proteins with different sequence features and *** evolutionary analyses further revealed that,although most floral genes have evolved under strong purifying selection,some have evolved under relaxed or changed constraints,as evidenced by the elevation of nonsynonymous substitution rates and/or the presence of positively selected *** together,these results suggest that the regulatory network for flower development has evolved rather rapidly,with changes in the composition,structure,and functional constraint of genes,as well as the interactions among them,being the most important contributors.

关键词： Arabidopsis evolution flower development regulatory network.

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2.& GUO ZhengTang 3 1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),Institute of Earth Environment,chinese academy of {2.,Xi’an 710075,china 2.graduate University of chinese academy of sciences,Beijing 100049,china 3 Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,chinese academy of {2.,Beijing 10002.,china State Key Laboratory of Loess and Quaternary Geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China graduate University of chinese academy of sciences Beijing 100049 China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2.m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2.m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern china during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积