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Simulation of sea surface temperature changes in the Middle Pliocene warm period and comparison with reconstructions

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Science Bulletin 2011年第9期56卷 892-901页

The Middle Pliocene (ca 3.12–2.97 Ma) is a recent warm period in the Earth’s history. In many respects, the warmth of the Middle Pliocene is similar to the probable warm situation of the late 21st century predicted by climate models. Understanding the Middle Pliocene climate is important in predicting the future climate with global warming. Here, we used the latest reconstructions for the Middle Pliocene—Pliocene research Interpretation and Synoptic Mapping (PRISM) version 3—to simulate the Middle Pliocene climate with a fully coupled model Fast Ocean Atmosphere Model. From comparison of the results of simulations with reconstructions, we considered two important scientific topics of Middle Pliocene climate modeling: extreme warming in the subpolar North Atlantic and a permanent El Ni?o in the tropical Pacific. Our simulations illustrate that the global annual mean sea surface temperature (SST) in the Middle Pliocene was about 2.3°C higher than that in the pre-industrial era. The warming was stronger at midand high latitudes than at low latitudes. The simulated SST changes agree with SST reconstructions in PRISM3 data, especially for the North Atlantic, North Pacific and west coast of South America. However, there were still discrepancies between the simulation of the SST and reconstructions for the subpolar North Atlantic and tropical Pacific. In the case of the Atlantic, the weakened meridional overturning circulation in the simulation did not support the reconstruction of the extremely warm condition in the subpolar North Atlantic. In the case of the tropical Pacific, the whole ocean warmed, especially the eastern tropical Pacific, which did not support the permanent El Ni?o suggested by the reconstruction. From evaluation of the modeling and reconstruction, we suggest that the above discrepancies were due to uncertainties in reconstructions, difficulties in paleoclimate modeling and deficiencies of climate models. The discrepancies should be reduced through cons

关键词： Middle Pliocene sea surface temperature permanent El Ni?o numerical modeling extreme warming

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Flow instability of buoyant-Marangoni convection in the LEC GaAs melt

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Science china(Technological Sciences) 2008年第4期51卷 397-406页

作者： CHEN ShuXian1 & LI MingWei2,3 1 Aviation Engineering Institute, Civil Aviation Flight University of china, Guanghan 618307, china 2 Institute of Power Engineering of Chongqing University, Chongqing 400030, china 3 research center of Biological Function Information and Instruments of Chongqing University by Sec-ond-Term National 985 Project, Chongqing University, Chongqing 400030, china Aviation Engineering Institute Civil Aviation Flight University of China Guanghan 618307 China Institute of Power Engineering of Chongqing University Chongqing 400030 China research center of Biological Function Information Instruments of Chongqing University by Second-Term National 985 Project Chongqing University Chongqing 400030 China

Flow transitions and instabilities have significant effects on the quality of the crystals. The flow and heat transfer in the LEC GaAs melt are numerically studied by a time-dependent and three-dimensional turbulent flow model. The effects of the change of the buoyancy and Marangoni force on the flow state are analyzed by changing the temperature difference between the crystal and the crucible walls. The results show that the flow will transform from axisymmetric steady flow to non-axisymmetric oscillatory flow when the temperature difference exceeds the critical value, and that the mechanism of the transition is attributed to the Marangoni instability. The critical temperature differences for the flow transitions corresponding to different melt depth H are numerically predicted. Several important characteristics of the non-axisymmetric buoyant-Marangoni convection are numerically observed and compared with that of the non-axisymmetric mixed convection coupled with crystal rotation.

关键词： flow transition flow instability buoyant-Marangoni convection mixed convection LEC GaAs melt

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Preparation and performances of bulk porous Al foams impregnated with phase-change-materials for thermal storage

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Progress in Natural Science:Materials International 2012年第5期22卷 440-444页

作者： Jinghua Jiang a,b,Yingying Zhu b,Aibin Ma a,b,Donghui Yang b,c,Fumin Lu b,Jianqing Chen b,Jun Shi b,Dan Song a,b a National Engineering research center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,nanjing 210098,china b College of Mechanics and Materials,Hohai University,nanjing 210098,china c Department of Mechanical and Aerospace Engineering,North Carolina State University,Raleigh,NC 27695-7919,USA [a] National Engineering research center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China [b] College of Mechanics and Materials Hohai University Nanjing 210098 China [c] Department of Mechanical and Aerospace Engineering North Carolina State University Raleigh NC 27695-7919 USA

Shape-stabilized phase change materials(PCMs) exhibit desirable thermal storage properties and are used for energy conservation *** study is focused on the preparation and thermal-/dynamic-mechanical properties of the bulk porous Al foams impregnated with organic PCMs such as paraffins and stearic *** results indicated that the new shape-stabilized PCMs composites could be produced by a simple and eco-friendly constant-pressure impregnation *** filling fraction of PCMs was approximately more than 80% for the impregnated samples with vacuuming or without *** shape-stabilized PCMs/Al-foam composites exhibited considerable latent thermal storage potential for good interface,desirable phase-change temperature range and latent heat values(72.9kJ/kg for the paraffin/Al-foam composite and 66.7kJ/kg for the stearic acid/Al-foam composite).Moreover,the impregnation of PCMs improved the dynamic-compression yield strength,durability and resistance to oxidation of Al foams and made its ideal energy-saving materials.

关键词： Phase change materials Porous Al foams Composites Thermal storage Dynamic mechanical properties

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Quantitative　model　for　species　distribution　of　hydroxy　polyaluminum　chloride

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Journal of Environmental Sciences 1997年第3期9卷 45-53页

作者： Feng Li, Luan Zhaokun, Tang Hongxiao research center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, china

The species distribution of hydroxy polyaluminum chloride (PAC, Al T=0.1mol/L) solutions prepared through two different types of base injection was studied and compared quantitatively by Al Ferron timed complex colorimetric method(AFM) and 27 Al NMR spectroscopy method (ANM), and was simulated by using a quantitative calculating procedure of chemical equilibrium in MINEQL model. The results suggest that methodology of synthesis is very important for determining species distribution in the preparation of PAC solutions. In the PAC solution prepared by micro injection of base method(MIBM), there are at least five kinds of species including a kind of monomeric species Al 3+ , three kinds of polymeric species Al 2(OH) 4+ 2, Al 7(OH) 4+ 17 , Al 13 O 4(OH) (7- n )+ 24+ n ( n =0,2)and an aggregate of Al 13 or a solid phase Al(OH) 3 (aq.). Whereas in the PAC solution prepared by instantaneous injection of base method (IIBM), there are a kind of monomeric species Al 3+ , two kinds of polymeric species Al 2(OH) 4+ 2, Al 13 O 4(OH) (7- n )+ 24+ n ( n =0,2) and a solid phase Al(OH) 3(am). The change of species distribution in the PAC solution depends on preparing method, B(OH/Al) value and concentration.

关键词： polyaluminum species distribution quantitative analysis model calculation.

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changes in wind speed over china during 1956-2004

Changes in wind speed over China during 1956-2004

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“2010年北京气象学会中青年优秀论文评选”学术研讨会

作者： Ying Jiang·Yong Luo·Zongci Zhao·Shuwang Tao nanjing University of Information Science and Technology, nanjing,Jiangsu,china center for Wind and Solar Energy Resources Assessment,CMA, Beijing,china National climate center,CMA, Beijing,china

Based on two observational data sets in china from 1956 to 2004,wind speed changes are *** annual mean wind speed(MWS),days of strong wind (SWDs),and maximum wind(MW) all show declining trends over broad areas of *** in the southeastern Tibetan Plateau and the regions from the Great Bend of the Yellow River southward to Yunnan and Guangxi Provinces wind speeds are not significantly reduced,but rather,in partial, these regions’ winds speeds are slightly *** regions with declining trends match the areas with relatively strong observed winds and the regions without significant declining trends match the areas with light observed *** the meantime,the regions with relatively strong winds correspond to areas of reduced days of *** for both increasing intensities and for the number of days of light winds both impact the installation of wind energy facilities. These may be advantageous to the development of wind energy in different ***,the change of anemometers,or relocation of stations are factors that are mildly responsible for the decreasing trend of *** main reason for the decreasing trend is that under the background of global warming,the contrasts of the sea level pressure,and near-surface temperature between the Asian continent and the Pacific Ocean have become significantly smaller,and the east Asian trough has shifted eastward and northward,and has weakened as *** East Asian winter and summer monsoons are decreasing,and all of these impacts have resulted in declines of MWS in china.

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Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern china. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity Environmental variability china

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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International research center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 1. Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

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Some evidence of drying trend over northern china from 1951 to 2004

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Chinese Science Bulletin 2006年第23期51卷 2913-2925页

作者： MA Zhuguo1,2 & FU Congbin1,2 1. Key Laboratory of Regional climate-Environment for Temperate East Asia, Chinese Academy of Sciences, Beijing 100029, china 2. START Regional center for Temperate East Asia, Institute of Atmos-pheric Physics, Chinese Academy of Sciences, Beijing 100029, china Key Laboratory of Regional climate-Environment for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China START Regional center for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over china were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern china in the last 54 years was revealed, and the evidence of drying trend over northern china was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest china and the central part of North china since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2) During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest china and the central part of North china in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast china, one was in the mid 1990s and the other two were in 1965 and 1983, respectively; (3) Unlike the variation trend of other subregions of northern china, the western part of Northwest china is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest china, the central part of North china and Northeast china since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions.

关键词：中国北方干燥趋向干旱索引气候背景

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Fate　of　pesticide　N’-(2,4-dimethylphenyl)-N-methylformamide　hydrochloride　in　simulated　aquatic　ecosystem

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Journal of Environmental Sciences 1997年第3期9卷 119-122页

作者： Yang Kewu, Mo Hanhong, An Fengchun research center for Eco Environmental Sciences, Chinese Academy of Science, Beijing 100085, china

The degradation and fate of pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride in simulated aquatic ecosystem were investigated. The results showed that the pesticide was not stable in simulated aquatic ecosystem with pH value of 7.4—8.9 and water temperature of 18.0—26.5℃. In the first 9 days, 95% of DMAH was disappeared, whereas the concentration of its degradation product 2,4 dimethylformanilide increased with time and was of a maximum value at about 9 days and then decreased. The concentration of 2, 4 dimethylaniline, which is another degradation product of DMAH, nearly did not change in the early of experiment. However, it decreased rapidly after 9 days. The experiment lasted 51 days. At the end of experiment, there were no N' 2, 4 dimethylphenyl) N methylformamidine, 2, 4 dimethylformanilide and 2, 4 dimethylaniline detected in water, but they were all detected in the sediment and water grass, and the total amount of them covered 2%—3% of application amount of DMAH. It indicated that water grass and sediment could absorb and concentrate these compounds.

关键词： pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride hydrolysis 2,4 dimethylformanilide 2,4 dimethylaniline.

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蛋白质折迭的不可逆热力学理论及蛋白质动态热力学结构(英文)

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生物化学与生物物理进展 2001年第3期28卷 429-435页

作者：赵钦一中国康复研究中心医学研究所北京100077

在机械力学及热力学基础上阐述蛋白质的各种物理性质是从物理学角度理解生物学的基础性工作 .详细讨论了蛋白质折迭的不可逆热力学理论 ,蛋白质动态热力学结构理论 .理论推断蛋白质动态热力学变化是一切生物学状态变化的基本热力学状态... 详细信息

在机械力学及热力学基础上阐述蛋白质的各种物理性质是从物理学角度理解生物学的基础性工作 .详细讨论了蛋白质折迭的不可逆热力学理论 ,蛋白质动态热力学结构理论 .理论推断蛋白质动态热力学变化是一切生物学状态变化的基本热力学状态单位并作为分子生物学变化的分子开关 .利用此理论解释了蛋白质的物理学性质及麻醉药的生物物理学机制 .

关键词：蛋白质动态热力学结构折迭蛋白质理论

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