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Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

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Science China Earth Sciences 2010年第S1期53卷 26-33页

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of China(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2 of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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Science China Chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao beijing national Laboratory for Molecular Sciences,State Key Laboratory for Structural Chemistry of Stable and Unstable Species Green Chemistry center,College of Chemistry and Molecular Engineering,Peking University,beijing 100871,China 1. beijing national Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing 100871 China2. Green Chemistry Center College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3.and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1,2-propanediol,and especially 1,2,5.pentanetriol were obtained with selectivities of 15.,14% and 22%,respectively,at 3.% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

基层医疗机构咳喘规范化诊疗能力提升示范项目评估标准(试行)

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中华全科医师杂志 2024年第5期23卷 431-441页

作者：国家卫生健康委能力建设和继续教育中心,《基层医疗机构咳喘规范化诊疗能力提升示范项目评估标准》制定专家组迟春花杨汀吴浩不详北京大学第一医院全科医学科北京大学第一医院健康管理中心北京100034 中日友好医院呼吸中心呼吸与危重症医学科国家呼吸医学中心北京100029 首都医科大学全科医学与继续教育学院

我国呼吸系统疾病患病率高、疾病负担严重、防控形势严峻。慢性阻塞性肺疾病(简称慢阻肺)目前仍然呈现高发态势,40岁以上人群的患病率高达13.7%,总患者人数近1亿[1];同时,慢阻肺是我国居民第3.死因,每年因慢阻肺死亡的人数占全球慢阻... 详细信息

我国呼吸系统疾病患病率高、疾病负担严重、防控形势严峻。慢性阻塞性肺疾病(简称慢阻肺)目前仍然呈现高发态势,40岁以上人群的患病率高达13.7%,总患者人数近1亿[1];同时,慢阻肺是我国居民第3.死因,每年因慢阻肺死亡的人数占全球慢阻肺死亡病例的3..1%[2]。更令人担忧的是,慢阻肺的诊断率却不尽如人意,仅为23.6%~3..0%,仅7.9%的患者接受常规药物治疗[3.。我国支气管哮喘(简称哮喘)防控形势也不容乐观,20岁以上人群患病率为4.2%,哮喘患者达45.0万(不包括症状不典型的哮喘患者),控制率仅28.7%[4,5.。研究报道慢性咳嗽患病率为2.0%~28.3.,以3.~40岁者最多[6]。

关键词：咳嗽肺疾病,慢性阻塞性哮喘呼吸困难呼吸道传染病慢病管理基层医疗机构标准

A comparison analysis between developed and undeveloped depressions over the South China Sea

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Acta Oceanologica Sinica 1989年第2期8卷 199-208页

作者： Liang Biqi Zhang Qiuqing Department of Atmospheric Sciences, Zhongshan University, Guangzhou, China national Research center for Marine Environment Forcasts, beijing, China Dept. of Atmospheric Sciences Zhangshan Univ. Guangzhou China. China

-- In this paper, by using two sets of composite data of developed and undeveloped depressions over the South China Sea, we analyze and compare the dynamic structures, the heating fields and the vorticity budget residuals of two different types of depressions. Our conclusions are as follows:The two types of depressions are similar in thermodynamical and dynamical structures. The main differ ences are : in the high layer of developed depression there is a divergence field, with a center near the zero line of vertical wind shear, and over undeveloped depression, the divergence field is weaker and the vertical wind at its center is greater than 5.m s-1. The thermodynamical field of the former is asymmetrical and that of the latter is quasi - symmetrical. As far as the dynamics structure is concerned, the convergence in the lower layer and the difference of divergence between the upper and lower layers of developed depression is three tmies larger than that of undeveloped depression. The upward motion and heating field at the center of developed depression is also stronger than that of undeveloped *** vorticity budget of the two types of depressions is mainly determined by the divergence term, the vorticity advection term and the vertical transport term. The residual term is also *** principal contribution comes from the divergence term . This is more significant for developed depression than for undeveloped depression.

关键词： over A comparison analysis between developed and undeveloped depressions over the South China Sea

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua University, beijing 100084, China center for Quantum Information, Tsinghua University, beijing 100084, China Department of Materials Science and Engineering, beijing Normal University, beijing 100875. China Testing and Analytical center, beijing Normal University, beijing 100875. China Department of Physics, beijing Normal University, beijing 100875. China 1. Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University 100084 Beijing China 2. center for Quantum Information Tsinghua University 100084 Beijing China 3. Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 4. Testing and Analytical center Beijing Normal University 100875 Beijing China 5. Department of Physics Beijing Normal University 100875 Beijing China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

Distribution characteristics of seamount cobalt-rich ferromanganese crusts and the determination of the size of areas for exploration and exploitation

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Acta Oceanologica Sinica 2011年第3期30卷 63-75页

作者： HE Gaowen MA Weilin SONG Chengbing YANG Shengxiong ZHU Benduo YAO Huiqiang JIANG Xunxiong CHENG Yongshou Guangzhou Marine Geological Survey Guangzhou 510075 China Second Institute of Oceanography State Ocean Administration Hangzhou 310012 China China Ocean Mineral Resources R ＆ D Association Beijing 100860 China beijing General Research Institute of Mining ＆ Metallurgy Beijing 100070 China national Marine Information center Tianjin 300171 China

In 2001, the International Seabed Authority （ISBA） initiated the consideration relating to the Regulations for Prospecting and Exploration for Hydrothermal Polymetallic Sulphides and Cobalt-rich Ferromanganese Crusts in the Area at its 7th session. Since then, the consideration of the Regulations has been mainly focused on the size of areas to be allocated for exploration and exploitation of the crusts. This paper, based on the investigation data and the analysis of the distribution characteristics of the crusts, suggests a model for determining the size of areas for exploration and exploitation of the crusts, taking into account various factors such as production scale, crust thickness and grade, mineable area proportion, recovery efficiency, exploration venture, and so on. Through the modeling, the paper suggests that the exploration area （the area covered by each application for approval of a plan of work for exploration of cobalt-rich crusts） shall be 4 85. km2 and the exploitation area （the mine site area） shall be 1 214 km2, for 20 years of 1 million wet tonnes annual production.

关键词： cobalt-rich ferromanganese crusts exploration and exploitation area seamounts regulation on exploration

Further research on high-spin structure in ^(161)Lu

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2,YU ShaoYing1,2,4,SHEN CaiWan1,5.LI XiaoWei6 & CHEN YongShou3.4 1 School of Science,Huzhou Teachers College,Huzhou 3.3.00,China 2 College of Mathematics,Physics and Information Engineering,Zhejiang Normal University,Jinhua 3.1000,China 3.China Institute of Atomic Energy,{5. 102413.China 4 Institute of Theoretical Physics,Chinese Academy of Sciences,{5. 100080,China 5.center of Theoretical Nuclear Physics,{3. Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,China 6 Department of Physics,Chifeng University,Chifeng 024001,China School of Science Huzhou Teachers College Huzhou 313000 China College of Mathematics Physics Information Engineering Zhejiang Normal University Jinhua 321000 China China Institute of Atomic Energy Beijing 102413 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China Department of Physics Chifeng University Chifeng 024001 China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2 in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13.2 also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

The Prediction of Maximum Amplitudes of Solar Cycles and the Maximum Amplitude of Solar Cycle 24

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Chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 557-562页

作者： Jia-Long Wang, Jian-Cun Gong, Si-Qing Liu, Gui-Ming Le and Jing-Lan Sun1 national Astronomical Observatories, Chinese Academy of Sciences, beijing 1000122 center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100080 center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080

We present a brief review of predictions of solar cycle maximum amplitude with a lead time of 2 years or more. It is pointed out that a precise prediction of the maximum amplitude with such a lead-time is still an open question despite progress made since the 1960s. A method of prediction using statistical characteristics of solar cycles is developed: the solar,cycles are divided into two groups, a high rising velocity (HRV) group and a low rising velocity (LRV) group, depending on the rising velocity in the ascending phase for a given duration of the ascending phase. The amplitude of Solar Cycle 24 can be predicted after the start of the cycle using the formula derived in this paper. Now, about 5.years before the start of the cycle, we can make a preliminary prediction of 83.2-119.4 for its maximum amplitude.

关键词： Sun : sunspots Sun : activity

Antarctic sea ice and ENSO event

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Acta Oceanologica Sinica 1993年第4期12卷 549-561页

作者： Hao Chunjiang, Zhang Lin, Xue Zhenhe and Xie Simei national Research center for Marine Environment Forecasts, State Oceanic Administration, beijing 100081, China national Research center for Marine Environment Forecasts State Oceanic Administration Beijing 10081 China. China

The characteristic low-frequency oscillation of the sea surface temperature anomaly (SSTA) of ENSO related regions, Nino 1 + 2, Nino 3. Nino 4 and Nino West, and the Southern Oscillation index (SOI) is analyzed with the method of maximum entropy spectrum. Antarctic sea ice is divided into 4 regions, i. e. East Antarctic is Region Ⅰ (0°-120° E), the region dominated by Ross Sea ice is Region Ⅱ (120° E-120° W), the region dominated by Ross Sea ice is Region Ⅲ (120° W-0°), and the whole Antarctic sea ice area is Region Ⅳ. Also, the month-to-month correlation series of the sea ice with ENSO from contemporary to 5.years lag is calculated. The optimum correlation period is selected from the series. The characteristics and the rules obtained are as follows.1. There are a common 4-years main period of the SSTA of Ninos 1 + 2,3.and 4, a rather strong 4-years secondary period and a quasi-8-years main period of that of Nino West. There are also 1. 5.and 2 to 3.years secondary periods of that of all 4 Nino regions.2. As another indicator of El Nino, the SOI represents the feature of the atmosphere in low latitude area, having a quasi-5.years main period; it also has secondary periods, 1, 1. 5.and 2 to 3.years, among them, the 2 to 3.years one is prominent.3. There is a close relationship between Antarctic sea ice and ENSO event. In the long-range correlation from contemporary up to 60 months of the SSTA in Ninos 1 + 2,3.and 4 and Antarctic sea ice area index, or the time series of 16 correlation coefficients made of each one of the 4 sea ice regions with that of the 4 Nino regions, there is a prominent common characteristic that all correlations are negative from contemporary to 3.-months lag of the SSTA of the 4 Nino regions behind Antarctic sea ice, the optimum correlation periods with the confidences equal to or more than 5.% , 1 % lagging in 13.19, 24-3. month are the most. The correlations of sea ice in Regions Ⅱ , Ⅲ and W with the SSTA of Ninos 3.and 4 are the strongest.

关键词： Nino Antarctic sea ice and ENSO event SSTA ENSO