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Two possible mechanisms for vortex self-organization

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science{1. Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1.& GAO Shouting3.1. Chinese Academy of Meteorological {1.s, Beijing 1.0081.{1. 2. Department of Space Information {1., {3. University of Information {1. and Technology, {3. 21.044,{1. 3. institute of Atmospheric Physics, Chinese Academy of {1.s, Beijing 1.0029,{1. 2. Department of Environmental science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological sciences Beijing 100081 China 3. {1. of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

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science{1. Earth sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1. CAI Keqin2 & YU Shengsong3.1. {1. {1. of Geography and Limnology, Chinese Academy of sciences,{3., china 2. china University of Geosciences, Beijing 1.0083. china 3. {1. of Salt Lakes, Chinese Academy of sciences, Xining 81.008, china 1. nanjing {1. of Geography and Limnology Chinese Academy of Sciences 210008 Nanjing China 2. china University of Geo{1.s 100083 Beijing China 3. {1. of Salt Lakes Chinese Academy of Sciences 810008 Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in china for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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science{1. Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1.2, ZHOU Guangqing1. YAN Changxiang1. FU Weiwei1.& YOU Xiaobao1.3.1. International Center for Climate and Environment {1.s, {1. of Atmospheric Physics, Chinese Academy of {1.s, Beijing 1.0029,{3. 2. Jiangsu Key Laboratory of Meteorological Disaster, nanjing University of Information {1. and Technology, nanjing 21.044,{3. 3. Beijing {1. of Applied Meteorology, Beijing 1.0029,{3. 1. International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. Beijing {1. of Applied Meteorology Beijing 100029 China

A new 3.VAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3.VAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21.year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 420 m reach 0.63. and 0.3. psu.

关键词： data assimilation, 3.VAR, sea surface height, ARGO floats.

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1.2, LI Anchun1. HU Ningjing2,3. FU Yongtao1. MA Zhibang4 1. {1. of Oceanology, Chinese Academy of {1.s, Qingdao 266071. china 2. Graduate School of the Chinese Academy of {1.s, Beijing 1.003., china 3. institute of soil science, Chinese Academy of {1.s, nanjing 21.008, china 4. {1. of Geology and Geophysics, Chinese Academy of {1.s, Beijing 1.0029, china 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the Chinese Academy of sciences Beijing 100039 China 3. institute of soil science Chinese Academy of Sciences Nanjing 210008 China 4. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong State Key Laboratory of soil and Sustainable Agriculture, {1. of soil {3., Chinese Academy of {3.s,nanjing 21.008, china [a]State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. Laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 1. d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

Characterization　of　Gleyization　of　Paddy　soils　in　the　Middle　Reaches　of　the　Yangtze　River

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Pedosphere 1996年第2期6卷 111-119页

作者： PAN SHUZHENG(institute of {1. science,Acodemia Silica,{3. 21.008 china) institute of {1. science Academia Sinica Nanjing 210008 China

The gleyisation of representative paddy soils in the middle reaches of the Yangtze caver was characterized,taking oxidation-reduction potential(Eh),the amount of active reducing substances and the forms of iron and manganese as the *** Eh value was linearly related with the logarithm of the amount of active reducing substances, which was contributed by ferrous iron by 8{1. on an *** degree of gleyization of dament horizons was graded as ungleyed,slightly gleyed,mildly gleyed and *** Eh of the four grades was>500,{1.0-500,1.0-{1.0 and1.0 mV,respectively, and the corresponding amoks of active reducing substances was1.1.7,7-{1. and>{1. ***(-1.,*** amount of ferrous iron of the four grades was 25 mmol kg-1.*** extent of gleyisation of a soil was classified as upper-gleyed, middle-gleyed and lower-gleyed, depending on whether the depth of the gley horbon was less than {1. cm,{1.-60 cm or more than 60 cm.

关键词： ferrous iron gleyization paddy soil reducing substances oxidation-reduction potential

A study of two-dimensional magnetic polaron

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science{1.(Physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1. ZHANG Huaihong1. FENG Mang1.2 & WANG Kelin1.3.1. School of {1., Southwest University of {1. and Technology, Mianyang 621.1., china 2. Wuhan {3. of Physics and Mathematics, Chinese Academy of {1.s, Wuhan 43.070, china 3. Department of Modern Physics, University of {1. and Technology of china, Hefei 23.026, china School of science Southwest University of Science Technology Mianyang 621010 China Wuhan institute of Physics Mathematics Chinese Academy of Sciences Wuhan 430070 China Department of Modern Physics University of Science Technology of china Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Prediction method for October 2003.solar storm

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science{1.(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State Key Laboratory of Space Weather, Center for Space science and Applied Research, Chinese Academy of sciences, Beijing 100080, china 2. Graduate School, Chinese Academy of sciences, Beijing 10003., china 3. institute of Meteorology, PLA University of science and Technology, nanjing 211101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 28 and 29, 2003. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1. and 3.1., re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau

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Chinese science Bulletin 1998年第5期43卷 409-412页

作者： TANG Keli+1. ZHANG Keli 1.2 and LEI Aling 1.3.1. {1. of {1. and Water Conservation, Chinese Academy of sciences, Yangling 71.1.0,{3. 2. Department of Hydraulic Engineering, Tsinghua University, Beijing 1.0084,{3. 3. Water Resources C institute of {1. and Water Conservation Chinese Academy of Sciences Yangling China Department of Hydraulic Engineering Tsinghua University Beijing China Water Resources Conservation Bureau of Yangtze River Ministry of Water Resources Wuhan China

Scientific evidence for the upper limit of farmland is proposed. Shallow gully erosion is one of erosion types distributed extensively on sloping farmland in the hilly regions of the Loess Plateau. Field observation and aerial photos interpretation, as well as laboratory experiments show that the shallow gully erosion occurring on the steeper farmland in the hilly regions of the Loess Plateau is an important factor leading to intensive erosion on slope, because of its extensive distribution and intensive runoff collection. The data on the formation, development and distribution of shallow gullies on sloping farmland indicate that critical slope gradient for shallow gully initiation ranges from 1. to 20 degrees with an average of 1..2 degrees. Therefore, it is suggested that critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau should be kept within the critical slope gradient for shallow gully initiation to prevent shallow gully formation in order to control soil loss more effectively. But as the first step, the cultivation on the slopes with slope larger than 25 degrees where the maximum erosion occurs should be strictly forbidden.

关键词： hilly region of Loess Plateau upper limitation for farmland shallow gully erosion erosion dynamic.