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The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor

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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. department of Environmental science, Chongqing {2., Campus A, Chongqing 400044, china 2. Key Laboratory for the Southwest china Resources Exploitation and Environmental Disaster Control Engineering, Ministry of Education, china.) department of Environmental science Chongqing University Campus A 重庆 400044

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 107 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 100% of nitrite was denitrified at up to about 0.8 g NO -_2.N/(L·d), which is 16 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 15 days with sludge from the reactor showed that 100% 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 15% 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

K-uniformly rotund spaces and k-uniformly smooth spaces

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Chinese science Bulletin 1998年第2期43卷 92-95页

作者： Suyalatu 1 and WU Congxin 2.1. department of Mathematics,Inner Mongolia Normal university, Huhhot 01002., {2. 2. department of Mathematics, Harbin Institute of technology, Harbin 150006, {2. department of Mathematics Inner Mongolia Normal University Huhhot China department of Mathematics Harbin Institute of Technology Harbin China

The conception of k_uniform smoothness (KUS) is introduced. It is the extension of the conception of uniform smoothness. It is proved that the k_uniform smoothness and Sullivan’s K_uniform rotundity (KUR) are the daul notions. X+* is a KUR space if and only if X is a KUS space, X+* is a KUS space if and only if X is a KUR space. If X is a KUS space, then X is a (K+1)US space. It is also proved that the KUS space includes the Nan’s k_strongly smooth space.

关键词： K_uniform smoothness K_uniform convexity.

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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science china Chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. department of Chemistry, Southwest-china Normal {2., Chongqing 400715, china 2. department of Chemistry, Sichuan {2., Chengdu 610064, china department of Chemistry Southwest-China Normal University Chongqing China department of Chemistry Sichuan University Chengdu China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

On three-dimensional geological modeling and visualization

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science china Earth sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. department of Resource Exploitation Engineering, china {2. of Mining and technology, Beijing 100083, china 2. Beijing Institute of Petrochemical technology, Beijing 102.17, china department of Resource Exploitation Engineering China University of Mining and Technology Beijing China Beijing Institute of Petrochemical technology Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. department of Mathematics, Hangzhou Normal university, Hangzhou 310036, {2. 2. department of Applied Mathematics, School of Mathematical sciences, South {2. university of technology, Guangzhou 510640, {2.) department of Mathematics Hangzhou Normal University Hangzhou 310036 China department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

A novel DNA computing model based on RecA-mediated triple-stranded DNA structure

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Progress in Natural science:Materials International 2007年第6期17卷 708-711页

作者： Fang Gang1, Zhang Shemin2. Dong Yafei1 and Xu Jin1(1. The Key Laboratory of Image Processing and Intelligent Control, department of Control science & Engineering, Huazhong {2. of science and technology, Wuhan 430074, china 2. Shaanxi {2. of technology, Hanzhong 72.000, china) Key Laboratory of Image Processing and Intelligent Control Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China Shaanxi university of technology Hanzhong 723000 China

The field of DNA computing emerged in 1994 after Adleman’s paper was published. Henceforth,a few scholars solved some noted NP-complete problems in this way. And all these methods of DNA computing are based on conventional Watson-Crick hydrogen bond of doublehelical DNA molecule. In this paper, we show that the triple-stranded DNA structure mediated by RecA protein can be used for solving computational problems. Sequence-specific recognition of double-stranded DNA by oligonucleotide-directed triple helix (triplex) formation is used to carry out the algorithm. We present procedure for the 3-vertex-colorability problems. In our proposed procedure, it is suggested that it is possible to solve more complicated problems with more variables by this model.

关键词： DNA computing 3-vertex-colorability problem.

Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key Laboratory for Mineral Deposits Research, Nanjing university, Nanjing 2.0093, china 2. East china Institute of technology, Fuzhou 344000, china) Nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E china Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

A new approximating method for Holstein model

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 44-48页

作者： REN XueZao 1 , LIAO Xu 1 , LI Lei 1 & WANG KeLin 2.1 School of science, Southwest university of science and technology, Mian Yang 62.010, china 2.department of Modern Physics, university of science and technology of china, hefei 2.002., china School of science Southwest University of Science and Technology Mian Yang China department of Modern Physics University of Science and Technology of China Hefei China

A new approach-the method of coherent state orthogonal expansion is developed for one-dimensional Holstein model. In zeroth order approximation, the formula of ground state energy is deduced analytically and the solutions in strong- and weak-coupling limits are obtained correctly. When the trial wave-function of ground state is expanded to the second order, the obtained ground state energy agrees quite well with that calculated by numerical method in all coupling regimes. The present approach can be easily generalized to the situations of higher dimensions and more electrons.

关键词： coherent-state orthogonal expansion polaron simulated annealing method

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

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science china Mathematics 2005年第10期48卷 1333-1348页

作者： XUE Liugen~1 & ZHU Lixing~2.1. College of Applied sciences,Beijing university of {2.,Beijing 10002.,china 2. department of Mathematics,Hong Kong Baptist university,Hong Kong,china College of Applied sciences Beijing University of Technology Beijing China department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.