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Scenario simulation and forecast of land use/cover in northern china

Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal university, Chongqing 400047, china 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044, china 3 college of Resources science & Technology, Beijing normal university, Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of Resources and Environmental science Chongqing University Chongqing China college of Resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

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Phototriggered Formation of a Supramolecular Polymer Network Based on Orthogonal H-Bonding and Host-Guest Recognition

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Chemical Research in Chinese Universities 2023年第5期39卷 777-781页

作者： BAI Ruixue YANG Xue ZHAO Jun ZHANG Zhaoming YAN xuzhou School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240P.R.China

Supramolecular polymer networks(SPNs)have gained increasing research attention due to their reversible and tunable nature in the preparation of adaptive *** use of hierarchical self-assembly techniques is an emerging strategy for the fabrication of smart supramolecular polymer networks,but corresponding study is still ***,we have reported a novel supramolecular polymer network through complementary host-guest interactions and phototriggered quadruple H-bonding ***,we design and synthesize an H1G1-type monomer consisting of a benzo-21-crown-7(B21C7)host(H1),a dialkylammonium salt guest(G1)and a photolabile o-nitrobenzyl ether protected ureidopyrimidinone(Upy)moiety.B21C7 and ammonium moieties can first form a linear supramolecular polymer through complementary host-guest *** photoirradiation,the Upy groups on the SP side chains were released,and the obtained linear supramolecular polymer could be further transformed into SPN through a quadruple H-bonding ***,the in situ transformation in the solid state is also accompanied by pronounced enhancement in mechanical properties,which provides foundation for further application of materials in different scenarios.

关键词： Host-guest recognition H-Bonding Phototriggered transformation Orthogonal

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Effects of Plasma Nitriding on Microstructure and Tribological Properties of CoCrMo Alloy Implant Materials

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Journal of Bionic Engineering 2010年第4期7卷 337-344页

作者： Qingliang Wang,Lei Zhang,Jiandong Dong School of Material science and Engineering,china university of Mining & Technology,xuzhou 221116,P.R.china School of Material science and Engineering China University of Mining & Technology Xuzhou P. R. China

Medical forged CoCrMo alloy was treated by plasma nitriding *** microstructures were characterized by 3Dprofiler,SEM and *** tribological properties were investigated under lubrication of 25% bovine serum *** that plasma nitriding is a promising process to produce thick,hard,and more wear resistant layers on the surface of *** nitrided samples showed an important increase in the surface hardness due to the formation of harder CrN andCrN phases with compact nano-crystalline *** typical hardness values of HVincreased almost two times thanuntreated *** bovine serum lubrication,at low nitriding temperature the Coefficient of Friction (COF) of nitrided samplewas lower than that of untreated sample,but at high nitriding temperature the COF was almost the same as the untreated *** with the untreated sample,the nitrided samples showed lower wear rates and higher wear resistance under differentnitriding *** adhesive wear is the main mechanism for untreated CoCrMo alloy and the wear mechanisms ofnitrided ones are the fatigue wear and slight adhesive *** is concluded that the improvement of wear resistance is ascribed tothe hard nitride formation of CrN and CrN phases at the nitrided surfaces.

关键词： CoCrMo alloy plasma nitriding microstructure friction and wear

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Crystal Structure of Methyl 3- (2-chlorophenyl )-3- (5, 5-dimethyl-3-hydroxy-2-cyclohexene- 1-one-2-yl) propionate

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Chinese Journal of Structural Chemistry 1998年第4期17卷 249-252页

作者： SHI Da-Qing LU Zai-Sheng TU Shu-Jiang WANG Su-Hui DAI Gui-Yuan(Department of Chemistry, xuzhou normal university, xuzhou 221009) 徐州师范大学化学系江苏徐州

The title compound C18H21ClO4 was synthesized by the reaction of 2-chlorobenzaldehyde, 5, 5-dimethyl-1, 3-cycfohexanedione and isopropylidene malonatein methanol catalyzed by KF-Al2O3 It crystallized in the monoclinic system, spacegroup P21/c, with a = 7. 587(2), b = 11. 736(3), c = 19. 120(7) A, β =101. 30°, V=1669.5(9) A 3, Dc= 1. 340 g/cm3, Z= 4, Mr= 336. 81, A= 0. 71069A, μ（MoKa) =2. 46 cm-1, F(000) = 712. The structure was refined to R=0. 034,Rw=0. 042 for 1468 observed refiections (I>3(I) ). X-ray analysis reveals that thedihedral angle between plane I[C(12)~C(17), Cl] and plane 2[O(1), O(2), C(1),C(2), C(3)] is 66. 98° and the C(11) atom exhibits a distorted tetrahedral configuration. The crystal structure shows that there is a conjugated enol form in the molecule.

关键词： methyl propionate synthesis crystal structure

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science china(Life sciences) 2009年第8期52卷 780-788页

作者： YANG Bo1,YANG SuYong2,ZHAO Lun3,YIN LiuHua1,LIU Xu1& AN ShaSha1 1 Laboratory of Psychology,School of Sociology,china university of Political science and Law,Beijing 102249,china 2 National Key Laboratory of Cognitive Neurosciences and Learning,Beijing normal university,Beijing 100875,china 3 Institute of Language,xuzhou normal university,xuzhou 221116,china Laboratory of Psychology School of Sociology China University of Political Science and Law Beijing China National Key Laboratory of Cognitive Neurosciences and Learning Beijing Normal University Beijing China Institute of Language Xuzhou Normal University Xuzhou China

Inhibitory control dysfunction is regarded as a core feature in *** major objective of this study was to explore the time course of response inhibition in chronic heroin addicts and provide the neurophysiological evidence of their inhibitory control *** amplitudes and latencies of ERP components were studied in fourteen heroin addicts(mean duration of heroin use being(13.54±5.71) years(Mean±SD),average abstinence being((4.67±6.44) months)) and fourteen matched healthy controls with a visual Go/Nogo *** results showed that heroin addicts demonstrated significantly larger Go-N2 amplitudes which results in a decreased N2 Go/Nogo effect,but no statistically significant differences were found between heroin addicts and controls in *** ERP data suggest that fronto-central areas of heroin addicts were impaired during the inhibition process(200-300 ms) and over-activated to *** impaired early process might reflect an abnormal conflict monitoring process in heroin *** results consolidate the inhibitory control dysfunction hypothesis in chronic heroin users.

关键词： heroin addicts events-related potentials inhibitory control conflict monitoring response inhibition

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Composition Operators Mapping into the E(p,q) Spaces

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Chinese Quarterly Journal of Mathematics 2003年第1期18卷 29-34页

作者： LIU Yong-min(Department of Mathematics, xuzhou normal university, xuzhou 221116, china) Departmentofmathematics XuzhouNormulUniversity Xuzhou 221116

Composition operators are used to study the E(p,q) spaces. The boundedness of these operators is also considered. The criteria for these operators to be bounded are given in terms of the Carleson measure.

关键词：复合算子映射有界性 Carleson测度复平面解析函数 Mobius变换 Littlewood从属原理双曲空间

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ON F-z-SUPPLEMENTED SUBGROUPS OF FINITE GROUPS

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Acta Mathematica Scientia 2011年第1期31卷 22-28页

作者：郭文彬唐娜李保军 Department of Mathematics University of Science and Technology of China Department of Mathematics Xuzhou Normal University Department of Mathematics Huaiyin Teachers College School of Mathematics Chengdu University of Information Technology

A subgroup H of a group G is called F-z-supplemented in G if there exists a subgroup K of G, such that G = HK and H∩K≤ Z∞F（G）, where Z∞F（G） is the F-hypercenter of G. We obtain some results about the F-z-suppl... 详细信息

关键词： Finite groups local formations F-z-supplemented subgroups supersoluble groups p-nilpotent groups

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Note about Fixed Points of Scott Continuous Self-Mappings

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Journal of Mathematical Research and Exposition 2011年第1期31卷 187-190页

作者： Xiao Yong XI1,2,Yong Ming LI3 1.college of Mathematics and Information science,Shaanxi normal university,Shaanxi 710062,P.R.china 2.college of Mathematics science,xuzhou normal university,Jiangsu 221009,P.R.china 3.college of Computer science,Shaanxi normal university,Shaanxi 710062,P.R.china college of Mathematics and Info'rmatio'n science Shaanxi Normat University Shaanxi 710062 college of Computer science Shaanxi Normal University Shaanxi 710062

It is discussed in this paper that under what conditions, for a continuous domain L, there is a Scott continuous self-mapping f ： L → L such that the set of fixed points fix（f） is not continuous in the ordering induced by L. For any algebraic domain L with a countable base and a smallest element, the problem presented by Huth is partially solved. Also, an example is given and shows that there is a bounded complete domain L such that for any Scott continuous stable self-mapping f, fix（f） is not the retract of L.

关键词： Scott continuous fixed points stable mapping.

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Static filtering and collocation in successive steps for measurements with colored noises

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中国有色金属学会会刊：英文版 2005年第S1期15卷 80-81页

作者： ZHAO Chang-sheng~1, MA Zhen-li~2 (1. xuzhou normal university, xuzhou 221009, china 2. Liaoning Technical university, Fuxin 123000, china)

The theory of static filtering in successive steps with colored noises is ample scope for its application in the procedure of GPS data processing. A majority of error and round-cycle distinctness in the measurements of GPS carrier phase can be eliminated through three times of differential calculations of stations, satellites and epochs, in which the cycle beatings became isolated values. The observation error of three-differentials in the intervals between epochs results in block diagonal matrixes in the covariance matrixes, so that the desired matrixes occupy too large memory and the processing time is too long. Therefore, by using the theory of static filtering in successive steps with colored noises, the interrelation can be eliminated and can save the processing time and memory.

关键词： colored noise static filtering in successive steps three-differentials measurements in GPS carrier phase

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Chromium leaching mechanism of coal mine water—a modeling study based on xuzhou-Datun coal mine district

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Mining science and Technology 2010年第1期20卷 97-102页

作者： SHAN Yao QIN Yong, WANG Wenfeng School of Resource and Earth science, china university of Mining & Technology, xuzhou 221116, china School of Resource and Earth science China University of Mining & Technology Xuzhou 221116 China

In order to investigate chromium contamination of coal mine water, to analyze chromium leaching mechanism and to evaluate environment pollution potential of coal mine water, we perform site investigations, physical and computer modeling in the xuzhou-Datun coal mine district. The result of our test samples shows that chromium concentration was 9 μg/L in roof leachate and 3 μg/L in coal leachate. The host rock has a higher pollution potential than that of coal seams. Leaching experiments and XRD test results indicate that chromium is released from the process of transforming illite to kaolinite. The pH, pe and temperature of coal mine water affect the chromium leaching behavior. Modeling results suggest that the adsorption of adsorbents controls chromium concentration in coal mine water. The chromium adsorption ratio is quite low in both an acid and in an alkaline environment. Therefore, coal mine water has a high pollution potential. Under other conditions, chromium adsorption is stronger in a neutral water environment, so that chromium concentrations may be very low.

关键词：计算机模拟铬浓度煤矿区矿水大屯矿区徐州机制淋溶

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