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Journal of Environmental sciences 2003年第3期15卷 423-432页

作者： ZHANG Dai-jun 1.2.(1. {1. of Environmental science, Chongqing University, Campus A, Chongqing 400044, {2. 2. Key Laboratory for the Southwest {2. Resources Exploitation and Environmental Disaster Control Engineering, Ministry of Education, {2..) department of Environmental {1. Chongqing University China

The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 1.7 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91. to 97% of COD were removed at up to about 3.9 g COD/(L·d) of COD volumetric loading rate. More than 97% to 1.0% of nitrite was denitrified at up to about 0.8 g NO -_2.N/(L·d), which is 1. times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05 gN/(L·d)). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 1. days with sludge from the reactor showed that 1.0% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 1.% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis.

关键词： methanogenesis denitrification ANAMMOX EGSB reactor

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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science {1. Chemistry 2004年第2期47卷 106-112页

作者： GONG Yubing1.2. HOU Zhonghuai1.& XIN Houwen1.1. {1. of Chemical Physics, University of science and Technology of {2., Hefei 2.002., {2. 2. {1. of Physics, Yantai Teachers University, Yantai 2.402., {2. 1. department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. {1. of Physics Yantai Teachers University 264025 Yantai China

The dynamical behavior of surface catalytic oxidation reaction of Pt(1.0)/CO+O2.modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(1.0)/CO+O2. supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1.2. Lu Daren2.and Sun Zhaobo1.1. Institute of atmospheric sciences, Nanjing University of Information science and Technology, Nanjing 2.0044, china 2. LAGEO, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 1.002., china) Institute of atmospheric {1.s Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1.58 to 2.01.using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 1..83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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science {1. Chemistry 2005年第5期48卷 395-401页

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

Reengineering Model of Supply Chain of Tea Industry in yunnan

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厦门大学学报（自然科学版） 2002年第S1期41卷 230-231页

作者： LI Yan-feng 1. JIANG Fa-kui 2.(1. Management School, Huazhong University of {1. and Technology, Wuhan 430074, china 2. {2. of Business Administration, yunnan University of Finance and Economics, kunming 6502.1. china)

yunnan University of finance and Trade recording to t he statistics of chain’s output of tea, yunnan province has entered the ranks of the larger ones of the production in {2.. yunnan’s tea industry has the natur al resources and the economic effects envied, on the orther hand, yunnan’s tea m arket has gradually become less and the economic effects have been poor. Through our comprehensive investigation and study, we consider that because the supply chain has seriously been disjointed among production, supply and sale of tea ind ustry in yunnan, the supply chain of yunnan’s tea industry need to be reorganize d for the promoting the development of yunnan’s tea industry. The essence of reengineering of yunnan’s tea industrial supply chain is to set u p the model of the trailed operation,to strengthen the strategic partnership man agement between the supply chain, to optimize the design of the supply chain and build up and improve the working mechanism for management of the tea industrial supply chain. The structure of yunnan’s model of tea industrial supply chain: the model of com mercial flow; the model of logistics flow; the model of information flow and the model of cash flow. The solutions and policies for the reorganization of yunnan’s tea industrial sup ply chain: planning, logistics and distribution and sales. Set up the supporting system of information technology. Build up the control system of production and *** the working mechanism of yunnan’s tea industrial supply chain. Implement the engineering of exporting yunnan’s tea into the markets of other p rovinces and foreign markets. Have many the channels that raise the funds of dev elopment for yunnan’s tea industry.

关键词： yunnan tea industry reengineering supply chain building model

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1.2.and Li Jianping2.1. College of atmospheric sciences, Lanzhou University, Lanzhou 730000, {2. 2. LASG, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 1.002., {2.) College of atmospheric {1.s Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1.48—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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science {1. Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1.SU Chun~2.& ZENG Yong~1.1. School of Management and School of Applied Mathematics,University of Electronic {1. and Technology of china,Chengdu 61.054,china 2. department of Statistics and Finance,University of {1. and Technology of china,Hefei 2.002.,china 1. School of Management and School of Applied Mathematics University of Electronic Science and Technology of China 610054 Chengdu China 2. {1. of Statistics and Finance University of Science and Technology of China 230026 Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

Abundant Semigroups with a Multiplicative Adequate Transversal

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Acta Mathematica Sinica,English Series 2002年第2期18卷 229-244页

作者： GUO Xiao Jiang department of Mathematics.{1. University.{2. 650091.P.R.china department of Mathematics Yunnan University Kunming P. R. China

The aim of this paper is to investigate abundant semigroups with a multiplicative adequate *** properties and characterizations for such semigroups are *** particular. we establish the structure of this class of abundant semigroups in terms of left normal bands,right normal braids and adequate semigroups with some simple Compatibility *** apply this structure to some special cases.

关键词： Abundant semigroup Adequate semigroup Left(Right)normal band

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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science {1. Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1. ZHUANG Guoshun1.2.3, SUN Yele1.& WANG Zifa3 1. The Center for {1. Environmental Study, department of Chemistry, Beijing Normal University, Beijing 1.0875, {2. 2. Center for {1. Chemistry Study, department of Environmental science & Engineering, Fudan University, Shanghai 2.0433, {2. 3. LAPC/NZC, Institute of {1. Physics, CAS, Beijing 1.002., {2. 1. The Center for atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for {1. Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of atmospheric Physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32.―67% of total suspended particles （TSP）, 1.%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （38%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM1., and 76% （59%―93%） in PM2.5 in spring, and 69% （52.―83%）, 79% （52.―93%）, and 45% （7%―79%） in TSP, PM1., and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Nonlinear local Lyapunov exponent and atmospheric predictability research

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science {1. Earth sciences 2006年第10期49卷 1111-1120页

作者： CHEN Baohua1. LI Jianping1.2.& DING Ruiqiang2.1. College of atmospheric sciences, Lanzhou University, Lanzhou 730000, {2. 2. State Key Laboratory of Numerical Modeling for atmospheric science and Geophysical Fluid Dynamics (LASG), Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 1.002., {2. 1. College of atmospheric {1.s Lanzhou University Lanzhou 730000 China 2. State Key Laboratory of Numerical Modeling for {1. science and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Because atmosphere itself is a nonlinear system and there exist some problems using the linearized equations to study the initial error growth, in this paper we try to use the error nonlinear growth theory to discuss its evolution, based on which we first put forward a new concept: nonlinear local Lyapunov exponent. It is quite different from the classic Lyapunov exponent because it may characterize the finite time error local average growth and its value depends on the initial condition, initial error, variables, evolution time, temporal and spatial scales. Based on its definition and the at-mospheric features, we provide a reasonable algorithm to the exponent for the experimental data, obtain the atmospheric initial error growth in finite time and gain the maximal prediction time. Lastly, taking 500 hPa height field as example, we discuss the application of the nonlinear local Lyapunov exponent in the study of atmospheric predictability and get some reliable results: atmospheric predictability has a distinct spatial structure. Overall, predictability shows a zonal distribution. Prediction time achieves the maximum over tropics, the second near the regions of Antarctic, it is also longer next to the Arctic and in subtropics and the mid-latitude the predictability is lowest. Particularly speaking, the average prediction time near the equation is 1.3}days and the maximum is located in the tropical Indian, Indonesia and the neighborhood, tropical eastern Pacific Ocean, on these regions the prediction time is about two weeks. Antarctic has a higher predictability than the neighboring latitudes and the prediction time is about 9 days. This feature is more obvious on Southern Hemispheric summer. In Arctic, the predictability is also higher than the one over mid-high latitudes but it is not pronounced as in Antarctic. Mid-high latitude of both Hemispheres (30°S―60°S, 30°―60°N) have the lowest predictability and the mean prediction time is just 3―4 d. In addition, predictab

关键词： nonlinear, local, Lyapunov exponent, atmospheric predictability, maximal prediction time.