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Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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chinese Science Bulletin 2009年第13期54卷 2300-2308页

作者： CHEN Jin1,2.3,WANG LiLi1,4.5,ZHU HaiFeng1 & WU Pu1 1 institute of Geographic {2. and Natural Resources Research,chinese academy of {2.,Beijing 100101,china 2.Graduate University of chinese academy of sciences,Beijing 10004.,china 3 institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of {2.,Beijing 10004.,china 4.institute of Tibetan Plateau Research,chinese academy of {2.,Beijing 100085,china 5 institute of Desert and Meteorology,china Meteorological Administration,ürümqi 830002.china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Desert and Meteorology China Meteorological Administration ürümqi 830002 China

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 184. to 2.00,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2. of the *** reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2.& JIANG Zonglin2.1. Key Laboratory of High Temperature Gas Dynamics, institute of Mechanics, chinese {2. of Sci- ences, Beijing 100080, china 2. Graduate University of{4., Beijing 100039, china 1. Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Graduate University of chinese academy of sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science china Earth sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2. ZHOU Kefa1, LOU Shaoping3 & YE Minquan4.1. Xinjiang institute of Ecology and Geography,{2., Urumqi 830011, china 2. institute of Geographical and Resources {4.,{2., Beijing 100101, china 3. Urumqi Meteorological-satellite Land Station, Urumqi 830011, china 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 830011, china Correspondence should be addressed to Chen Xi 1. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences 830011 Urumqi China 2. institute of Geographical and Resources sciences Chinese Academy of Sciences 100101 Beijing China 3. Urumqi Meteorological-satellite Land Station 830011 Urumqi China 4. Seismological Bureau of Xinjiang Uygur Autonomous Region 830011 Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, china, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 4. years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 4. years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 4. years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2. the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3) the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

Use of DNA barcode sensu lato to identify traditional Tibetan medicinal plant Gentianopsis paludosa(Gentianaceae)

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Journal of Systematics and Evolution 2011年第3期49卷 267-270页

作者： Chun-Ying XUE* De-Zhu LI(Key Laboratory of Biodiversity and Biogeography,Kunming institute of botany,{2. academy of {4.,Kunming 6502.4.china) (Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) *Correspondence: Chun-Ying XUE *Correspondence: ?Author for correspondence. E-mail: chyxue@*** Tel.: 86-871-52.3508 Fax: 86-871-52.7791.

Gentianopsis paludosa(Hook.f.) Ma(Gentianaceae) is an important species in Tibetan folk medicine commonly used to clear away the "heat evils" and toxic materials.A survey of market samples revealed that nine adulterant species,Gentianopsis barbata,***,***,Halenia elliptica,Lomatogonium macranthum,***,Swertia angustifolia,*** and ***,are often marketed as *** to distinguish *** from its adulterants are limited by current morphological and chemical *** sequence analysis of the nuclear ribosomal DNA internal transcribed spacer region(ITS) was used in the differentiation of *** from the adulterant *** data showed that the internal transcribed spacer regions differ significantly between *** and all nine adulterant species,so that they could be easily distinguished at the DNA level.

关键词： Gentianaceae Gentianopsis paludosa identification nrDNA ITS Tibetan medicine.

中国经济发展的机遇与挑战——学习中央经济工作会议精神座谈会综述

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中国工业经济 2024年第1期 5-16页

作者：中国社会科学院工业经济研究所课题组史丹不详中国社会科学院工业经济研究所

2.2.年12.11—12.,中央经济工作会议在北京举行。习近平总书记出席会议并发表重要讲话,全面总结2.2.年经济工作,深刻分析当前经济形势,系统部署2.2.0}经济工作。会议要求,2.2.0}要坚持稳中求进、以进促稳、先立后破,多出有利于稳预期... 详细信息

2.2.年12.11—12.,中央经济工作会议在北京举行。习近平总书记出席会议并发表重要讲话,全面总结2.2.年经济工作,深刻分析当前经济形势,系统部署2.2.0}经济工作。会议要求,2.2.0}要坚持稳中求进、以进促稳、先立后破,多出有利于稳预期、稳增长、稳就业的政策,在转方式、调结构、提质量、增效益上积极进取,不断巩固稳中向好的基础。要强化宏观政策逆周期和跨周期调节,继续实施积极的财政政策和稳健的货币政策,加强政策工具创新和协调配合。为深入解读2.2.年中央经济工作会议精神,中国社会科学院工业经济研究所“我国发展的新战略机遇与风险挑战研究”课题组邀请7位专家学者交流学习体会,立足当前经济走势,回应当下经济热点问题,为推动高质量发展建言献策。

关键词：高质量发展宏观政策科技创新城乡融合绿色低碳

Mantle-derived rare-gas releasing features at the Tianchi volcanic area, Changbaishan Mountains

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chinese Science Bulletin 1997年第9期42卷 768-771页

作者： SHANGGUAN Zhiguan and SUN Mingliang1. institute of Geology, State Seismological Bureau, Beijing 10002., china 2. Lanzhou institute of Geology, chinese academy of sciences, Lanzhou 730000, china institute of Geology State Seismological Bureau Beijing China Lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China

TIANCHI volcano,Changbaishan Mountains isthe largest modern active volcano in East *** times strong volcanic erupting activ-ities occurred in the Cenozoic *** vol-canic activities have revived again in the *** investi... 详细信息

关键词： Tianchi volcanic area Changbaishan Mountains mantle-derived rare gas 3He/ 4.e 4. Ar/36 Ar 4.e/2. Ne 4.e/4.Ar isotope ratios.

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science china Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2. YAO Tandong2.1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, Lanzhou 730000, {2. 2. institute of Tibetan Plateau Research, chinese academy of sciences, Beijing 100085, {2. 1. Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 2.th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102.years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2.3 , HU Chen 2., WANG JianMin 2., BIAN WeiHao 4., ZHANG Shu 2.& ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of sciences, Beijing 100012. {2. 2.Key Laboratory for Particle Astrophysics, institute of High Energy Physics, chinese academy of sciences, Beijing 10004., {2. 3 Graduate University of the chinese academy of sciences, Beijing 10004., {2. 4.Department of Physics, Nanjing Normal University, Nanjing 2.0011, {2. 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 2.1 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental sciences, Peking University, Beijing 100871, china 2. LAPC, {2. of Atmospheric Physics, chinese academy of sciences, Beijing 10002., china 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.