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Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast china

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Chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2.3. ZHOU GuangSheng1,4.& WANG Yu1,3.1 State Key Laboratory of Vegetation and Environmental Change, institute of Botany, Chinese Academy of Sciences, beijing 100093. {3. 2.institute of {4. Environment, {3. Meteorological Administration, Shenyang 110016, {3. 3.Graduate University of Chinese Academy of Sciences, beijing 10004., {3. 4.Chinese Academy of Meteorological Sciences, beijing 100081, {3. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China institute of atmospheric Environment China Meteorological Administration Shenyang 110016 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Chinese Academy of Meteorological Sciences Beijing 100081 China

Based on continuous three-year measurements (from 2.04.to 2.07) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast china. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2.m-2.d-1, and the lowest occurred in late November. The average Rs of non-growing season was 4.6.06 ± 2..01 g CO2.m-2. accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P3.%-70%. When soil water content was more than 0.1 m3.m-3. soil moisture at 10 cm depth was significantly parabolically correlated with Rs (P3.-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 2..4. of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast china.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应

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Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2.3. ZHANG Yong1,2.3. ZHAO Feng1,2.3. GU Xingfa1,3.4. ZHU Li1,2.3. WANG Pengxin5 & MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate University of Chinese Academy of Sciences, {3. 10003., china 3. The Center for National Spaceborne Demonstration, {3. 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 5. College of Information and Electrical Engineering, china Agricultural University, {3. 100083. china 6. china Center for Resource Satellite Data and Application, {3. 10083., china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate University of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of Information and Electrical Engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and Environmental School, Lanzhou University, Lanzhou 73.000, {2. 2. Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 73.000, {2. 3. College of Resources Science & Technology, {4. Normal University, {4. 100875, {2. 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~{2.e/~4.e in almost all samples range from 0.82.Ra to 2.74.Ra, whereas^(4.)Ar/^({2.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~{2.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~{2.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3., ZHAO Xia~4. SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, {2. of High Energy physics, Chinese Academy of Sciences, {3. 10004., china 2. Graduate School of Chinese Academy of Sciences, {3. 10004., china 3. Department of physics, Zhoukou Normal University, Zhoukou 4.6100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, {2. of Automation, Chinese Academy of Sciences, {3. 10004., china 6. Department of physics, Zhejiang University, Hangzhou 3.002., china) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]Department of physics Zhoukou Normal University Zhoukou China [d]Research Imaging Center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

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Light A physics in the lepton-specific two-Higgs doublet model

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1981-1987页

作者： CAO JunJie 1,HENG ZhaoXia 2.3.& WAN PeiHua 1 1 College of physics & Information Engineering,Henan Normal University,Xinxiang {2.3.07,china 2.Key Laboratory of Frontiers in Theoretical physics,institute of Theoretical physics,Chinese Academy of Sciences,beijing 100190,china 3.Kavli institute for Theoretical physics china,Chinese Academy of Sciences,beijing 100190,china 1. College of physics & Information Engineering Henan Normal University Xinxiang 453007 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 China

We examine various direct and indirect constraints on the lepton-specific two-Higgs doublet model and discuss its phenomenology at colliders in the allowed parameter *** constraints we consider come from the precision electroweak data,the direct search for Higgs boson,the muon anomalous magnetic moment,as well as some theoretical consistency *** find that in the allowed parameter space the CP-odd Higgs boson A is rather light (m A 3. GeV with 95% possibility),which is composed dominantly by the leptonic Higgs and decays dominantly into τ + τ;while the SM-like Higgs boson h (responsible largely for electroweak symmetry breaking) decays dominantly in the mode h → AA → 4. with a large decay width,which will make the Higgs discovery more difficult at the ***,this scenario predicts rare Z decays Z → AAA and Z →τ + τA with their branching ratios ranging from 10-8 to 10-and 10-5 to 10-4.respectively,which may be accessible at the GigaZ option of the ILC.

关键词： Lepton-specific two-Higgs doublt model light Higgs boson A Z decays

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The principle of relativity, kinematics and algebraic relations

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2.3. WU HongTu4.& ZHOU Bin5 1{2. of Theoretical physics, Chinese Academy of Sciences, {3. 100190, china 2.2. of High Energy physics, Chinese Academy of Sciences, {3. 10004., china 3.heoretical physics Center for Science Facilities, Chinese Academy of Sciences, {3. 10004., china 4.epartment of Mathematics, Capital Normal University, {3. 10004., china 5Department of physics, {3. Normal University, {3. 100875, china 1. institute of Theoretical physics Chinese Academy of Sciences Beijing 100190 China2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China4. Department of Mathematics Capital Normal University Beijing 100048 China5. Department of Physics Beijing Normal University Beijing 100875 China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

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The formation and stability of Si_(1-x)C_x alloys in Si implanted with carbon ions

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Chinese Science Bulletin 2001年第3期46卷 200-204页

作者： WANG Yinshu, LI Jinmin, JIN Yunfan, WANG Yutian, SUN Guosheng & LIN Lanying1. Department of physics, beijing Normal University, beijing 100875, {3. 2. {4. of Semiconductors, Chinese Academy of Sciences, beijing 100083. {3. 3. {4. of Modern physics, Chinese Academy of Sciences, Lanzhou 73.000, {3. Department of physics Beijing Normal University Beijing China institute of Semiconductors Chinese Academy of Sciences Beijing China institute of Modern physics Chinese Academy of Sciences Lanzhou China

Si1-xCx alloys of carbon (C) concentration between 0.6%-1.0% were grown in Si by ion implantation and high temperature annealing. The formation of Si1-xCx alloys under different ion doses and their stability during annealing were studied. If the implanted dose was less than that for amorphizing Si crystals, the implanted C atoms would like to combine with defects produced during implantation and it was difficult to form Si1-xCx alloys after being annealed at 850℃. With the increment of implanted C ion doses, the lattice damage increased and it was easier to form Si1-xCx alloys. But the lattice strain would become saturate and only part of implanted carbon atoms would occupy the substitutional positions to form Si1-xCx alloys as the implanted carbon dose increased to a certain degree. Once Si1-xCx alloys were formed, they were stable at 950℃, but part of their strain would release as the annealing temperature increased to 1 000℃. Stability of the alloys became worse with the increment of carbon

关键词： ion implantation Si1-xCx alloys stability of Si1-xCx alloys.

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EXAFS Studies on Local Atomic Structure in the Amorphous Mg_(65)Cu_(2.)Gd_(10) Alloy

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 98-101页

作者：李国强 Business Development Department China Perfect Machinery Industry Corp. Ltd

Local atomic structures of an amorphous Mg65Cu2.Gd10 alloy and the structural changes by thermal annealing have been studied by extended X-ray absorption fine structure （EXAFS）. The correlation between structural changes and mechanical properties for the Mg65Cu2.Gd10 alloy has also been discussed. Results showed that Cu atoms around Gd in Mg65Cu2.Gd10 lost rapidly during annealing , resulting in the segregation of Cu atoms. The coordination number NGd-Mg of Mg65Cu2.Gd10 annealed at 3.3.K first diminished and then augmented with the increase of annealing time. The formation of polyhedral short-range order unit with coordination number of nearly 12.around Gd atoms is in favor of the improvement of mechanical properties. The chemical short-range order, not topological short-range order in the amorphous Mg65Cu2.Gd10 alloy had obvious changes during annealing.

关键词： magnesium alloy amorphous alloy short-range EXAFS mechanical properties annealing

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Numerical simulation of topography effects on the “00.7” severe rainfall in beijing

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Progress in Natural Science:Materials International 2005年第9期15卷 818-826页

作者： ZHANG Chaolin1**, JI Chongping1, KUO Yinghwa2. FAN Shuiyong1, XUAN Chunyi3.and CHEN Min1(1. institute of Urban Meteorology, {2. Meteorological Administration, beijing 100089, {2. 2. Mesoscale and Microscale Meteorology Division, National Center for {4. Research, Boulder, CO 803.7-3.00, USA 3. beijing Meteorological Bureau, beijing 100089, {2.) institute of Urban Meteorology China Meteorological Administration Beijing 100089 China. Mesoscale and Microscale Meteorology Division National Center for Atmospheric Research Boulder CO 80307-3000 USA. beijing Meteorological Bureau Beijing 100089 China

In an effort to study the severe rainfall event of 4.5th July 2.00 in beijing (with 2.0} accumulated precipitation of 2.0} mm), we perform numerical simulations to investigate this event using the MM5v3.6 model. The model is initialized with the MM5/WRF 3.VAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional meteorological observations in its assimilation step. For 2.0}h accumulated precipitation forecast, the threat scores are 0.72. 0.76, 0.67 and 0.63. for thresholds of 1, 5, 10, and 2. mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 50 and 3.7 km to investigate the topographic effects on precipitation over the beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.

关键词： topography heavy rainfall 3.VAR ground-based GPS numerical simulation.

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Forecasting the summer rainfall in North china using the year-to-year increment approach

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Science china Earth Sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2.& GAO YuZhong3.1 Nansen-Zhu International Research Center, institute of {2. physics, Chinese Academy of Sciences, {3., {4. 2.Graduate University of the Chinese Academy of Sciences, beijing 10004., {4. 3.Heilongjiang Meteorological Administration, Harbin 15003., {4. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Heilongjiang Meteorological Administ

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the {2. circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2.00-2.07, with an average relative root mean square error of 2.% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2.06. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

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