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Small-Scale Spatial Variability of Soil Nutrients and Vegetation Properties in Semi-Arid Northern china

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Pedosphere 2006年第6期16卷 778-787页

作者： CHEN Fu-Sheng ZENG De-Hui HE Xing-Yuan Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shengyang 110016 （China） life College Nanchang University Nanchang 330047 （China）

A field experiment was conducted at Kezuohouqi County, Inner Mongolia Autonomous Region of china, which was located on the southeastern edge of the Horqin Sandy Land, to study the spatial variability of soil nutrients for a smallscale, nutrient-poor, sandy site in a semi-arid region of northern china; to investigate whether or not there were 'islands of fertility' at the experimental site; and to determine the key nutrient elements that sustained ecosystem stability. Results obtained from geostatistical analysis indicated that the spatial distribution pattern of soil total nitrogen (STN) was far different from those of soil organic matter (SOM), total phosphorus (STP), and total potassium (STK). Compared to SOM, STP, and STK, STN had a lower structural heterogeneity ratio and a longer range, while other elements were all similar. In addition, STN had an isotropic spatial structure, whereas the others had an anisotropic spatial structure. The spatial structure patterns of herbage species, cover,and height also differed, indicating that spatial variability was subjected to different ecological factors. Differences in the spatial variability patterns among soil nutrients and vegetation properties showed that soil nutrients for a small-scale were not the primary limiting factors that influenced herbage spatial distribution patterns. Incorporating spatial distribution patterns of tree species, namely, Pinus sylvestris var. mongolica Litv. and shrub Lespedeza bicolor Turcz. in a research plot and using fractal dimension,SOM, STP, and STK were shown to contribute to the 'islands of fertility' phenomenon, however STN was not, possibly meaning that nitrogen was a key limiting element. Therefore, during restoration of similar ecosystems more attention should be given to soil nitrogen.

关键词： Pinus sylvestris war. mongolica Litv. semi-arid region soil nutrients spatial variability species richness

Polymorphisms of three gene-derived STS on pig chromosome 13q41 are associated with susceptibility to enterotoxigenic Escherichia coli F4ab/ac in pigs

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science china(life sciences) 2008年第7期51卷 614-619页

作者： HUANG Xiang 1 ,REN Jun 1 ,YAN XueMing 1,2 ,PENG QiuLing 1 ,TANG Huan 1 ,ZHANG Bo 1 ,JI HuaYuan 1 , YANG ShuJin1&HUANG LuSheng 1 1Key Laboratory for Animal Biotechnology of Jiangxi Province and the Ministry of Agriculture of china,Jiangxi Agricultural university, nanchang 330045,china 2Department of Biology,nanchang university of science and Technology,nanchang 330038,china Key Laboratory for Animal Biotechnology of Jiangxi Province and the Ministry of Agriculture of china Jiangxi Agricultural University Nanchang China Department of Biology Nanchang University of Science and Technology Nanchang China

Neonatal diarrhea caused by enterotoxigenic Escherichia coli(ETEC)F4 is a common and serious disease,resulting in significant economical loss in the pig *** locus encoding ETEC F4 receptor has been mapped to pig chromosome(SSC)13q41,and one of the most significantly linked markers is *** this study,we selected three genes including SLC12A8,MYLK and KPNA1 from a chromosomal region flanking S0075 on SSC13 to develop pig specific sequence tagged sites(STS). Seven single nucleotide polymorphisms were identified in the three pig STS using DNA of four full-sib susceptible and resistant animals in a White Duroc×Erhualian *** grandparents,parents and 755 offspring in the intercross were genotyped for three polymorphisms,including SLC12A8 g.159A>G,MYLK g.1673A>G and KPNA1 g.306A>***-based transmission disequilibrium test(TDT) revealed that all polymorphisms and the corresponding haplotypes are significantly associated with ETEC F4ab/ac(especially F4ac)brush border adhesion phenotypes,indicating that these polymor- phism are in linkage disequlibrium with causal mutation(s)of the gene encoding ETEC F4ab/ac receptor. Our results strengthen the evidence for the involvement of SSC13q41 in high acquiring risk of ETEC F4ab/ac infection,and provide novel polymorphic markers for fine mapping of the ETEC F4ab/ac receptor locus.

关键词： pig SSC13q41 sequence tagged sites(STS) Escherichia coli(ETEC)F4ab/ac susceptibility

Effects of substitution and terminal groups for liquid-crystallinity enhanced luminescence of disubstituted polyacetylenes carrying chromophoric terphenyl pendants

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中国科学：化学英文版 2010年第6期53卷 1302-1315页

作者： ZHOU Dan,CHEN YiWang,CHEN Lie,LI Fan,NIE HuaRong & YAO Kai Institute of Polymers/Department of Chemistry,nanchang university,nanchang 330031,china Institute of Polymers/Department of Chemistry Nanchang University Nanchang China

Liquid-crystalline and light-emitting poly(2-alkyne)s containing terphenyl cores with hexamethyleneoxy spacers,and cyano or n-propoxy tails -[CH3C=C(CH2)6O-terphenyl-R]n-,where R=CN,CH3PA6CN,R=OCH2CH2CH3,CH3PA6OPr,were *** effects of the substitution and terminal groups on the properties,especially the mesomorphic and optical properties of the polymers,were *** disubstituted acetylene monomers (CH3A6CN,CH3A6OPr) were pre- pared through multistep reaction routes and were polymerized by WCl6-Ph4Sn in good yields (up to 82%).All the monomers and CH3PA6CN exhibited the enantiotropic SmA phase with a monolayer arrangement at elevated temperatures,whereas CH3PA6OPr formed a bilayer SmAd packing *** excitation at 330 nm,strong UV and blue emission peaks at 362 and 411 nm were observed in CH3PA6OPr and CH3PA6CN,*** luminescent properties of CH3PA6CN and CH3PA6OPr have been improved by introducing the methyl substituted group,and the quantum yield of the polymer with cyano tail CH3PA6CN (φ= 74%) was found to be higher than that of CH3PA6OPr (φ= 60%).Compared to polyacety- lene parents,both CH3PA6OPr and CH3PA6CN showed a narrower energy *** demonstrated that the electrical con- ductivities of polyacetylenes could be enhanced by attaching appropriate pendants to the conjugated polyene backbones.

关键词： disubstituted polyacetylenes liquid crystallinity phase transition photoluminescence

Effects of pH on the peripheral light-harvesting antenna complex for Rhodopseudomonas palustris

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science china(life sciences) 2008年第8期51卷 760-766页

作者： FENG Juan, LI XueFeng & LIU Yan school of life science and Technology, university of Electronic science and Technology of china, Chengdu 610054, china school of life science and Technology University of Electronic Science and Technology of China Chengdu China

In this work steady-state absorption spectroscopy, circular dichroism spectroscopy and sub-micro-second time-resolved absorption spectroscopy were used to investigate the effect of pH on the struc-tures and functions of LH2 complex for Rhodopseudomonas palustris. The results revealed that: (1) B800 Bchla was gradually transformed to free pigments absorbing around 760 nm on the minutes timescale upon the induction of strong acidic pH, and subsequently there disappeared the CD signal for Qy band of B800 in the absence of B800. In addition, Carotenoids changed with the similar tendency to B850 BChl. (2) The introduction of strong basic pH gave rise to no significant changes for B800 Bchla, while B850 BChla experienced remarkable spectral blue-shift from 852 to 837 nm. Similar phe-nomenon was seen for the CD signal for Qy band of B850. Carotenoids displayed strong and pH-independent CD signals in the visible range. (3) In the case of both physiological and basic pH, broad and asymmetrical positive Tn←T1 transient absorption appeared following the pulsed photo-excitation of Car at 532 nm. By contrast, the featureless and weak positive signal was observed on the sub-microsecond timescale in the acidic pH environment. The aforementioned experimental results indicated that acidic pH-induced removal of B800 Bchla prevented the generation of the caro-tenoid triplet state (3Car*), which is known to be essential for the photo-protection function. Neverthe-less, carotenoids can still perform this important physiological role under the basic pH condition, where the spectral blue shift of B850 exerts little effect on the overall structure of the cyclic aggregate, therefore favoring the formation of carotenoid triplet state.

关键词： pH-induced B800-removal triplet state photo-protection function

Fuzzy Neural Network PID Controller for seam tracking

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微计算机信息 2006年第25期 71-73页

作者： (Robot&Welding Automation Key Laboratory, nanchang U-niversity, nanchang 330029, china)Xiao,Min Zhang,Hua Jia, Jianping (school of information Engineering, nanchang university, nanchang 330029,china)

A Fuzzy Neural Network PID Controller is proposed in this paper, Fuzzy Neural Network Controller is used to optimize the parameters of PID Controller real time. Computer simulation using MATLAB shows that, comparing to the classical PID Controller, Fuzzy Neural Network PID Controller can improve the precision of control results for seam tracking.

关键词： self-adaptation PID Fuzzy neural network.

A SEMI-ANALYTICAL SOLUTION FOR CHARACTERISTICS OF A DAMRESERVOIR SYSTEM WITH ABSORPTIVE RESERVOIR BOTTOM

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Journal of Hydrodynamics 2008年第6期20卷 727-734页

作者： LI Shang-ming LIANG Hong LI Ai-min school of Civil Engineering and Architecture Nanchang University Nanchang 330031 China

In this study, a semi-analytical formulation based on the Scaled Boundary Finite Element Method （SBFEM） was proposed and used to obtain the solution for the characteristics of a two-dimensional dam-reservoir system with absorptive reservoir bottom in the frequency domain. For simplicity, the dam with arbitrary upstream faces was assumed to be rigid and was subjected to a horizontal ground acceleration, while the reservoir with absorptive bottom was assumed to be semi-infinite. The reservoir was divided into two sub-domains： a near-field sub-domain and a far-field sub-domain. The near-field sub-domain with arbitrary geometry was modelled by the Finite Element Method （FEM）, while the effects of the far-field sub-domain which was assumed to be horizontal were described by a semi-analytical formation. The semi-analytical formulation involved the effect of absorptive reservoir bottom, as well as the radiation damping effect of a semi-infinite reservoir. A FEM/SBFEM coupling formulation was presented to solve dam-reservoir coupled problems. The accuracy and efficiency of the coupling formulation were demonstrated by computing some benchmark examples. Highly accurate results are produced even if the near-field sub-domain is very small.

关键词： dam-reservoir interaction absorptive bottom SBFEM Hydraulic pressure FEM/SBFEM coupling formulation

A SIMULATIONAL STUDY OF PRECIPITATION KINETICS AND MORPHOLOGY IN NITRIDATION OF ALLOY STEELS

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Journal of Shanghai Jiaotong university(science) 2000年第1期5卷 298-302页

作者： Lang Zhou, Xiuqin Wei and Zhangmin Deng school of Chemistry and Materials science, nanchang university, nanchang 330047, P.R. china

An atomic model of compound precipitation in alloys, which couples cellular automaton growth/dissociation of precipitates and randomwalk diffusion, has been developed and programmed for 2 dimensional computer simulation. With boundary condition parameters and diffusion parameters variable, a series of simulation experiments were carried out for a qualitative study of nitride precipitation behavior in nitridation of alloy steels. Effects of nitrogen potential and alloy composition on kinetics and microstructure of the precipitation were addressed, and the so called "iso-activity aging" phenomenon was examined.

关键词： Simulation Cellular automaton Precipitation Nitridation

SIMULTANEOUS DETERMINATION OF MULTICOMPONENT IN MIXED ACIDS BY MATHEMATICAL METHOD

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Chinese Chemical Letters 1990年第2期1卷 105-108页

作者： Yong Nian NI Department of Chemistry,Jiangxi university,nanchang,330047

A new method for the determination of components in mixed acids has been *** mathematical model is obtained from samples of known composition and is then used to predict the concentrations of components in unknown *** practical utility of this method is demonstrated for simultaneous determination of two systems of ternary mixed acids and the results are satisfactory.

关键词： acid SIMULTANEOUS DETERMINATION OF MULTICOMPONENT IN MIXED ACIDS BY MATHEMATICAL METHOD

The Design and Simulation of the 2-D micro-carving parallel robot

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微计算机信息 2006年第1Z期22卷 221-223页

作者： (school of Mechanical and Electronic Engineering,nanchang university,nanchang 330029,china) Ye,Jianxiong Zhang,Hua Tan,Manhua Wei,Hui

A convenient and effective close loop control scheme, based on the analysis of the robot structure and its control link, has been proposed to satisfy the 2D mini-parallel-carve robot design in this paper. With the introduction of sequent deduction and reversed simulation in the conceiving phase, but more important, with the adoption of the proper restriction to reassure the exclusive result of coordinate transformation and movement planning, the equipment is designed and completed finally with satisfy conclusion.

关键词：机器人结构分析智能控制误差分析