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1Some evidence of drying trend over northern China from 1951 to 2004显示文摘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.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 2006Chinese Science Bulletin2006,51,23:63
2Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago显示文摘A typical sequence of fluvial terraces and aeolian deposits overlying these terraces were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identified. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 samples). The luminescence dating and stratigraphic correlation suggest that terraces of T11, T10,T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, respectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace sequence provides an ideal geological record of the uplift process of the northeastern Qinghai-Tibet during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 million years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the T11 and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the northeastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts. There was a significant readjustment of the fluvial catchment during 1.55-1.2 million years ago: before this time, the paleoriver flowed to southwest. After this time the Huangshui River flows to southeast. A tectonic movement dominates reorganization of this fluvial system.LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 4. Department of Geography, Qinghai Normal University, Xining 810008, China 2004Science China Earth Sciences2004,47,9:51
3The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, China显示文摘Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42―4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42 Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.21 Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.MA Yuzhen 1 , FANG Xiaomin 1,2 , LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western China’s Environmental Systems and College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2005Science China Earth Sciences2005,48,5:31
4Direct numerical simulation of shock/turbulent boundary layer interaction in a supersonic compression ramp显示文摘A direct numerical simulation of the shock/turbulent boundary layer interaction flow in a supersonic 24-degree compression ramp is conducted with the free stream Mach number 2.9.The blow-and-suction disturbance in the upstream wall boundary is used to trigger the transition.Both the mean wall pressure and the velocity profiles agree with those of the experimental data,which validates the simulation.The turbulent kinetic energy budget in the separation region is analyzed.Results show that the turbulent production term increases fast in the separation region,while the turbulent dissipation term reaches its peak in the near-wall region.The turbulent transport term contributes to the balance of the turbulent conduction and turbulent dissipation.Based on the analysis of instantaneous pressure in the downstream region of the mean shock and that in the separation bubble,the authors suggest that the low frequency oscillation of the shock is not caused by the upstream turbulent disturbance,but rather the instability of separation bubble.LI XinLiang1,FU DeXun2,MA YanWen2 & LIANG Xian1 1 Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China 2 The State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China 2010Science China(Physics,Mechanics & Astronomy)2010,53,9:24
5Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South China Sea显示文摘The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South China Sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2,4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.LI MeiJun1,WANG TieGuan1,LIU Ju2,ZHANG MeiZhu2,LU Hong3,MA QinLin2 & GAO LiHui2 1 State Key Laboratory of Petroleum Resources and Prospecting,Earth Sciences and Geoinformatics School,China University of Petroleum,Beijing 102249,China 2 Southern Oil Exploration and Development Company,PetroChina,Guangzhou 510640,China 3 Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510240,China 2008Science China Earth Sciences2008,51,S2:24
6Changes in individual plant traits and biomass allocation in alpine meadow with elevation variation on the Qinghai-Tibetan Plateau显示文摘Plant traits and individual plant biomass allocation of 57 perennial herbaceous species,belonging to three common functional groups (forbs,grasses and sedges) at subalpine (3700 m ASL),alpine (4300 m ASL) and subnival (≥5000 m ASL) sites were examined to test the hypothesis that at high altitudes,plants reduce the proportion of aboveground parts and allocate more biomass to belowground parts,especially storage organs,as altitude increases,so as to geminate and resist environmental stress.However,results indicate that some divergence in biomass allocation exists among organs.With increasing altitude,the mean fractions of total biomass allocated to aboveground parts decreased.The mean fractions of total biomass allocation to storage organs at the subalpine site (7%±2% S.E.) were distinct from those at the alpine (23%±6%) and subnival (21%±6%) sites,while the proportions of green leaves at all altitudes remained almost constant.At 4300 m and 5000 m,the mean fractions of flower stems decreased by 45% and 41%,respectively,while fine roots increased by 86% and 102%,respectively.Specific leaf areas and leaf areas of forbs and grasses deceased with rising elevation,while sedges showed opposite trends.For all three functional groups,leaf area ratio and leaf area root mass ratio decreased,while fine root biomass increased at higher altitudes.Biomass allocation patterns of alpine plants were characterized by a reduction in aboveground reproductive organs and enlargement of fine roots,while the proportion of leaves remained stable.It was beneficial for high altitude plants to compensate carbon gain and nutrient uptake under low temperature and limited nutrients by stabilizing biomass investment to photosynthetic structures and increasing the absorption surface area of fine roots.In contrast to forbs and grasses that had high mycorrhizal infection,sedges had higher single leaf area and more root fraction,especially fine roots.MA WeiLing1,2,SHI PeiLi1*,LI WenHua1,HE YongTao1,ZHANG XianZhou1,SHEN ZhenXi1 & CHAI SiYue1,2 1Lhasa National Ecological Research Station,Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 2Graduate University of Chinese Academy of Sciences,Beijing 100049,China 2010Science China(Life Sciences)2010,53,9:19
7Preliminary study on the origin identification of natural gas by the parameters of light hydrocarbon显示文摘The light hydrocarbon composition of 209 natural gas samples and individual light hydrocarbon carbon isotopes of 53 natural gas samples from typical humic-sourced gas and sapropelic-sourced gas in the four basins of China have been determined and analyzed.Some identification parameters for humic-sourced gas and sapropelic-sourced gas are proposed or corrected.The differences of compound-specificδ13C value of individual light hydrocarbon between humic-sourced gas and sapropelic-sourced gas have been founded.The humic-sourced gas has the distribution ofδ13C benzene > -24‰,δ13C toluene >-23‰,δ13C cyclohexane >-24‰andδ13C methyl cyclohexane >-24‰,while the sapropelicsourced gas has the distribution ofδ13C benzene <-24‰,δ13C toluene <-24‰,δ13C cyclohexane <-24‰and δ13C methyl cyclohexane <-24‰.Among the components of C7 light hydrocarbon compound,such as normal heptane(nC7),methyl cyclohexane(MCH)and dimethyl cyclopentane(ΣDMCP),etc,relative contents of nC7 and MCH are influenced mainly by the source organic matter type of natural gas.Therefore,it is suggested that the gas with relative content of nC7 of more than 30%and relative content of MCH of less than 70%is sapropelic-sourced gas,while gas with relative content of nC7 of less than 35%and relative content of MCH of more than 50%is humic-sourced gas.Among components of C5-7 aliphatics, the gas with relative content of C5-7 normal alkane of more than 30%is sapropelic-sourced gas,while the gas with relative content of C5-7 normal alkane of less than 30%is humic-sourced gas.These paremeters have been suggested to identify humic-sourced gas and sapropelic-sourced gas.HU GuoYi 1,2,3 ,LI Jian 1,2 ,LI Jin 1,2 ,LI ZhiSheng 1,2 ,LUO Xia 1,2 ,SUN QingWu 1,2 &MA ChengHua 1,2 1 Research Institute of Petroleum Exploration and Development(Langfang Branch),Petrochina,Langfang 065007,China 2 The Key Laboratory of Gas Formation and Development,Petrochina,Langfang 065007,China 3 College of Geo-Resources and Information,China University of Petroleum,Beijing 102200,China 2008Science China Earth Sciences2008,51,S1:19
8Dynamic calculation model and seismic response for frame supporting structure with prestressed anchors显示文摘A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed. The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope. The lateral displacement of frame and soil is nearly in phase. The movement characteristic satisfies the theory of elastic foundation beam. The frame is treated with elastic foundation beam in this model. The influence of prestressed anchors is simplified as linear spring and damped system related with velocity. Under the condition of horizontal earthquake excitation, the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration. This method is applied to a case record for illustration of its capability, in order to verify the method, 3D nonlinear FEM (ADINA) is used to analyze the seismic performance of this case, the comparative results show that the design and the analysis are safe and credible by using the proposed method. The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.DONG JianHua1’2, ZHU YanPeng1, ZHOU Yong1 & MA Wei2 1 College of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China 2 State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2010Science China(Technological Sciences)2010,53,7:16
9Influence of obstacle disturbance in a duct on explosion characteristics of coal gas显示文摘In combination with experimental research,numerical simulation is performed to investigate the influence law of the obstacles in a duct on the explosion flame of premixed coal gas and air. The numerical method uses upwind WENO scheme and two-step chemical reaction model. The interaction mechanism is addressed between the compression wave from reflection on the right end of the duct and flame propagation. The reflected wave is found to result in the decrease of flame velocity. On this basis,we analyze the mechanism of the obstacles on flame as well as the law of flow field variation thus caused. The results suggest that,due to the obstacles,deflagration wave is repeatedly reflected,combustible gas mixture is fully compressed,temperature and pressure rise,chemical reaction speed increases,and hence flame intensity is strengthened. At the same time,a tripe point forms as a result of wall reflection of the deflagration wave from the obstacles and furthermore local flame speed increases. As the triple point propagates forward,the flame speed gradually decreases due to dissipation of energy. These conclusions provide a valuable theoretical foundation for the prediction of explosion field,prevention of fire and explosion and effective control of the com-bustion speed and flame propagation speed in detonation propulsion.WANG Cheng1,MA TianBao1 & LU Jie2 1 State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China 2 Taiyuan Gas Company,Taiyuan 030024,China 2010Science China(Physics,Mechanics & Astronomy)2010,53,2:16
10Experimental investigation of the influence of electric field on frost layer growth under natural convection condition显示文摘直接电流(DC ) 的影响一个冷垂直盘子上的霜的厚度和团上的电场被调查。生长有或没有电场的存在被拿,并且结果的霜层的相片证明电走在霜厚度上有强烈影响。霜厚度和霜质量上的冷板温度和周围的温度的影响也与电场在自然传送对流条件下面被调查。试验性的结果证明冷板温度在霜层厚度,而是它对霜质量的影响上有很强壮的效果是次要的;对霜团的影响或周围的温度在霜厚度上是比那更明显的。ZHANG Xinhua, LIU Zhongliang, WANG Jieteng, GOU Yujun, MENG Sheng and MA Chongfang Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education Key Laboratory of Heat Transfer and Energy Conversion, Beijing Education Commission, Beijing University of Technology, Beijing 100022, China 2006Progress in Natural Science:Materials International2006,16,4:16
11Screening Methods for Waterlogging Tolerance at Maize (Zea mays L.) Seedling Stage显示文摘Waterlogging strongly affects agronomic performance of maize (Zea mays L.). In order to investigate the suitable selection criteria of waterflooding tolerant genotypes, and identify the most susceptible stage and the best continuous treatment time to waterlogging, 20 common maize inbred lines were subjected to successive artificial waterflooding at seedling stage, and waterlogging tolerance coefficient (WTC) was used to screen waterflooding tolerant genotypes. In addition, peroxidase (POD) activities and malondialdehyde (MDA) contents were measured for 6 of 20 lines. The results showed that the second leaf stage (V2) was the most susceptible stage, and 6 d after waterflooding was the best continuous treatment time. Dry weight (DW) of both shoots and roots of all lines were significantly reduced at 6 d time-point of waterlogging, compared to control. POD activities and MDA contents were negatively and significantly correlated, and the correlation coefficient was -0.9686 (P < 0.0001). According to the results, WTC of shoot DW can be used for practical screening as a suitable index, which is significantly different from control and waterlogged plants happened 6 d earlier. Furthermore, leaf chlorosis, MDA content and POD activities could also be used as reference index for material screening. The implications of the results for waterlogging-tolerant material screening and waterlogging-tolerant breeding have been discussed in maize.LIU Yong-zhong, TANG Bin, ZHENG Yong-lian, MA Ke-jun, XU Shang-zhong and QIU Fa-zhan National Key Laboratory of Crop Genetic Improvement/Huazhong Agricultural University, Wuhan 430070, P.R.China 2010Agricultural Sciences in China2010,9,3:16
12Simultaneous adsorption of lead and cadmium on MnO_2-loaded resin显示文摘MnO2-loaded D301 weak basic anion exchange resin has been used as adsorbent to simultaneously remove lead and cadmium ions from aqueous solution.The effects of adsorbent dosage,solution pH and the coexistent ions on the adsorption were investigated.Experimental results showed that with the adsorbent dosage more than 0.6 g/L,both Pb 2+ and Cd2+ were simultaneously removed at pH range 5-6.Except for HPO 42+ ,the high concentration coexistent ions such as Na + ,K + ,Cl+ ,NO3-,SO42+ and HCO3-,showed no significant effect on the removal efficiency of both Pb2+ and Cd2+ under the experimental conditions.The coexistence of Mg2+ ,Ca2+ caused the reduction of Cd2+ removal,but not for Pb2+ .The adsorption equilibrium for Pb2+ and Cd 2+ could be excellently described by the Langmuir isotherm model with R2 > 0.99.The maximum adsorption capacity was calculated as 80.64 mg/g for Pb2+ and 21.45 mg/g for Cd2+ .The adsorption processes followed the pseudo first-order kinetics model.MnO2-loaded D301 resin has been shown to have a potential to be used as an effective adsorbent for simultaneous removal of lead and cadmium ions from aqueous solution.Lijing Dong,Zhiliang Zhu,Hongmei Ma,Yanling Qiu,Jianfu ZhaoState Key Laboratory of Pollution Control and Resource Reuse,Tongji University,Shanghai 200092,China 2010Journal of Environmental Sciences2010,22,2:16
13Interactions between hotspots and the Southwest Indian Ridge during the last 90 Ma:Implications on the formation of oceanic plateaus and intra-plate seamounts显示文摘This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian Ocean.We first calculated the relative distance between the Southwest Indian Ridge (SWIR) and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy isostasy.The results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction (73.6-68.5 Ma),interaction with the SWIR (68.5-42.7 Ma),and intra-plate volcanism (42.7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,respectively.The magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge distance.The periodicity of the Marion hotspot is about 25 Ma,which is much longer than that of the Hawaii and Iceland hotspots (about 15 Ma).ZHANG Tao 1,2,3,4,LIN Jian 5 & GAO JinYao 3,4 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 The Second Institute of Oceanography,State Oceanic Administrator,Hangzhou 310012,China 4 Key Laboratory of Submarine Geosciences,State Oceanic Administrator,Hangzhou 310012,China 5 Department of Geology and Geophysics,Woods Hole Oceanographic Institution,Woods Hole,MA 02543,USA 2011Science China Earth Sciences2011,54,8:16
14Application of cusp catastrophe theory to reliability analysis of slopes in open-pit mines显示文摘A method of slope reliability analysis was developed by imposing a state equation on the limit equilibrium theory, given the basis of a fixed safety factor technique. Among the many problems of reliability analysis, the most important problem is to find a performance function. We have created a new method of building a limit state equation for planar slip surfaces by applying the mathematical cusp catastrophe theory. This new technique overcomes the defects in the traditional rigid limit equilibrium theory and offers a new way for studying the reliability problem of planar slip surfaces. Consequently, we applied the technique to a case of an open-pit mine and compared our results with that of the traditional approach. From the results we conclude that both methods are essentially consistent, but the reliability index calculated by the traditional model is lower than that from the catastrophic model. The catastrophe model takes into consideration two possible situations of a slope being in the limit equilibrium condition, i.e., it may or may not slip. In the traditional method, however, a slope is definitely considered as slipping when it meets the condition of a limit equilibrium. We conclude that the catastrophe model has more actual and instructive importance compared to the traditional model.YANG Kun, WANG Tongxu, MA Zhitao Key Laboratory of Mine Disaster Prevention and Control, Shandong University of Science and Technology, Qingdao 266510, China 2010Mining Science and Technology2010,20,1:15
15Evaluation of ecosystem services of Chinese pine forests in China显示文摘Evaluation of forest ecosystem services is a hot topic,both in China and at abroad,but it has not yet obtained a consistency of evaluation indicator systems and evaluation methods.Under the framework of evaluation criteria to be implemented for forest ecosystem services,years of consecutive observation data from Long Term Ecological Research Stations affiliated to Chinese Forest Ecosystem Research Network(CFERN),forest resource inventory and public data were applied to carry out a detailed and dynamic evaluation on the physical quantity and value of ecosystem services of Chinese pine forests in China.The results showed that the above services had the total value and unit value of 1144.9640 billion(1.1449640×10 12 )RMB and 52.074 thousand RMB per hectare per year,respectively during the 9th Five-year Plan(1996―2000),and of 1190.5461 billion RMB and 52.101 thousand RMB per hectare per year,respectively,during the 10th Five-year Plan(2001―2005).For Chinese pine forests,water conservation was 40.40 hundred million cubic meters annually,soil conservation was 67 million tons and C fixation 9 million tons annually,production of healthful negative ions was 1.96×10 20 , absorption of SO2 was 5.02 hundred million kilograms and dust-catching was 759.10 hundred million kilograms. Among the 15 provinces of China with Chinese pine forests,the biggest beneficiary from ecosystem services was Liaoning Province;while Hunan Province was the smallest beneficiary between the 9th Five-year Plan.GUO Hao ,WANG Bing,MA XiangQian,ZHAO GuangDong&LI ShaoNing Research Institute of Forest Ecology Environment and Protection of CAF,Key Laboratory of Forest Ecological Environment of State Forestry Administration,Beijing 100091,China 2008Science China(Life Sciences)2008,51,7:14
16Clostridium difficile infections in China显示文摘Clostridium difficile (C. difficile) infection has become one of the major hospital-associated infections in West-ern countries in the last two decades. However, there is limited information on the status of C. difficile infection inChinese healthcare settings. Given the large and increasing elderly population and the well-recognized problem ofover-prescribing of broad spectrum antibiotics in China, it is critical to understand the epidemiology and potentialrisk factors that may contribute to C. difficile infection in China. A literature review of available published studies,including those in Chinese language-based journals, was conducted. A review of the currently available literaturesuggested the presence of C. difficile infections in China, but also suggested that these infections were not particu-larly endemic. This finding should lead to better designed and greatly expanded studies to provide a more reliableepidemiologically-based conclusion on the actual status of C. difficile infection in China, including the identifica-tion of any associated risk factors. Such information is ultimately valuable to develop appropriate strategies to pre-vent C. difficile infection and the vast negative impact of such infections in China and other developing countries.Ke Jin a,b,c,Shixia Wang c,d,Zuhu Huang a,b,c,Shan Lu b,c,daDepartment of Infectious Diseases,bJiangsu Province Key Laboratory in Infectious Diseases,cChina-US Vaccine ResearchCenter,the First Affiliated Hospital of Nanjing Medical University,Nanjing,Jiangsu 210029,China d Department of Medicine,University of Massachusetts Medical School,Worcester,MA 01655,USA. 2010The Journal of Biomedical Research2010,24,6:14
17Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core显示文摘Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.XIANG Shurong1, YAO Tandong1, 2, AN Lizhe1, 3, WU Guangjian2, XU Baiqing2, MA Xiaojun 3, LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions 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 3. College of Life Science, Lanzhou University, Lanzhou 730000, China 2005Science China Earth Sciences2005,48,10:12
18Catalytic performance of Fe_3O_4-CoO/Al_2O_3 catalyst in ozonation of 2-(2,4-dichlorophenoxy) propionic acid,nitrobenzene and oxalic acid in water显示文摘Fe3O4-CoO/Al2O3 catalyst was prepared by incipient wetness impregnation using Fe(NO3) 3·9H2O and Co(NO3) 2·6H2O as the precursors,and its catalytic performance was investigated in ozonation of 2-(2,4-dichlorophenoxy) propionic acid(2,4-DP) ,nitrobenzene and oxalic acid.The experimental results indicated that Fe3O4-CoO/Al2O3 catalyst enabled an interesting improvement of ozonation eciency during the degradation of each organic pollutant,and the Fe3O4-CoO/Al2O3 catalytic ozonation system followed a radical-type mechanism.The kinetics of ozonation alone and Fe3O4-CoO/Al2O3 catalytic ozonation of three organic pollutants in aqueous solution were discussed under the mere consideration of direct ozone reaction and OH radical reaction to well investigate its performance.In the catalytic ozonation of 2,4-DP,the apparent reaction rate constants(k) were determined to be 1.456×10-2 min-1 for ozonation alone and 4.740×10-2 min-1 for O3/Fe3O4-CoO/Al2O3.And O3/Fe3O4-CoO/Al2O3 had a larger Rct(6.614×10-9) calculated by the relative method than O3 did(1.800×10-9) ,showing O3/Fe3O4-CoO/Al2O3 generated more hydroxyl radical.Similar results were also obtained in the catalytic ozonation of nitrobenzene and oxalic acid.The above results demonstrated that the catalytic performance of Fe3O4-CoO/Al2O3 in ozonation of studied organic substance was universal to a certain degree.Shaoping Tong,Rui Shi,Hua Zhang,Chunan Ma College of Chemical Engineering and Materials Science,State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology,Zhejiang University of Technology,Hangzhou 310032,China 2010Journal of Environmental Sciences2010,22,10:10
19Proteomic analysis of mitochondria reveals a metabolic switch from fatty acid oxidation to glycolysis in the failing heart显示文摘This work characterizes the mitochondrial proteomic profile in the failing heart and elucidates the molecular basis of mitochondria in heart failure. Heart failure was induced in rats by myocardial infarction, and mitochondria were isolated from hearts by differential centrifugation. Using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry, a system biology approach was employed to investigate differences in mitochondrial proteins between normal and failing hearts. Mass spectrometry identified 27 proteins differentially expressed that involved in energy metabolism. Among those, the up-regulated proteins included tricarboxylic acid cycle enzymes and pyruvate dehydrogenase complex subunits while the down-regulated proteins were involved in fatty acid oxidation and the OXPHOS complex. These results suggest a substantial metabolic switch from free fatty acid oxidation to glycolysis in heart failure and provide molecular evidence for alterations in the structural and functional parameters of mitochondria that may contribute to cardiac dysfunction during ischemic injury.WANG Jun1,2, BAI Ling1,2, LI Jing3, SUN ChaoFeng1,2, ZHAO Jin1, CUI ChangCong1,2, HAN Ke1,2, LIU Yu1,2, ZHUO XiaoZhen1,2, WANG TingZhong1,2, LIU Ping1,2, FAN FenLing1,2, GUAN YouFei3 & MA AiQun1,2 1 Department of Cardiology, First affiliated hospital of medical college of Xi’an Jiaotong University, Xi’an 710061, China 2 Ion Channel Disease Laboratory, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry, Xi’an 710061, China 3 Department of Physiology and Pathophysiology Key Laboratory of Molecular Cardiovascular Sciences of the Ministry of Education, Peking University Health Science Center, Beijing 100083, China 2009Science China(Life Sciences)2009,52,11:10
20Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis显示文摘The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the region.Comparisons to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the observed.SWAT model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic precipitation.In deeper soil layers,high soil moisture appears in the river basins and plains.The regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2004,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.LI MingXing1,2,MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Shaanxi Administration of Meteorology,Xi’an 710014,China 2010Science China Earth Sciences2010,53,4:9
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