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Responses of Soil Fauna Structure and Leaf Litter Decomposition to Effective Microorganism Treatments in Da Hinggan Mountains,China

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Chinese Geographical Science 2012年第6期22卷 647-658页

作者： GAO Meixiang LI Jingke zhang xueping Key Laboratory of Remote Sensing Monitoring of Geographic Environment College of Heilongiiang Province Harbin Normal University Harbin 150025 China Yecheng Trading Co. Ltd. Dandong 118000 China

Microorganisms are nutritious resources for various soil *** soil fauna grazing affects microorganism composition and decomposition rate,the responses of soil fauna and leaf litter decomposition to added microorganism is little *** this study,in the coniferous and broad-leaved mixed forest of Tahe County in the northern Da Hinggan Mountains,China,three sampling sites(each has an area of 10 m2) were *** first two sites were sprinkled with 250 times(EM1) and 1000 times(EM2) diluted effective microorganism(EM) preparations evenly,and the third site was sprinkled with the same volume of water as a control *** responses of soil fauna structure and leaf litter decomposition to EM treatment were conducted during three *** results revealed that EM treatment resulted in significant increase of soil organic *** number of soil fauna in the EM1 and EM2 sites increased by 12.88% and 2.23% compared to the control site,and among them springtails and mites showed the highest ***,the groups of soil fauna in the EM1 and EM2 sites decreased by 6 and 9,*** the changes in the diversity and evenness index were relatively *** treatment slowed the decomposition of broad-leaved litter,but accelerated the decomposition of coniferous ***,the decomposition rate of broad-leaved litter was still higher than that of coniferous *** results of this study suggested that the added microorganisms could help individual growth of soil fauna,and this method led to a change in the process of leaf litter *** paper did not analyze the activity of soil microorganisms,thus it is difficult to clearly explain the complex relationships among litter type,soil fauna and soil *** research on this subject is needed.

关键词： soil fauna leaf litter decomposition effective microorganism treatment Da Hinggan Mountains China

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Dynamics of Soil Fauna in Da Hinggan Mountains, Northeast China

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Chinese Geographical Science 2009年第2期19卷 151-157页

作者： zhang xueping SUN Yuan HUANG Lirong College of Geographical Sciences Harbin Normal University Harbin 150025 China College of Agricultural Resources and Environment Heilongjiang University Harbin 150080 China Sugar Beet Research Institute Chinese Academy of Agricultural Sciences Harbin 150080 China School of Resource and Environment Science Liaoning University Shenyang 110036 China

The dynamics of soil animals was studied in seven representative forest communities in the north of the Da Hinggan Mountains, Northeast China. The results indicate that it was distinctive in the changes of the numbers of soil animals and groups and diversity in relationship with seasons for macrofauna and meso-micro fauna in the study area. The numbers of the observed soil animals in different months were: October>August>June. Group number was larger in August and October, but smaller in June. The change of diversity index in different months was: August>June>Oc- tober. The biomass for macrofauna in different months was: October>June>August. The composition and number of each functional group was relatively stable. In the community of the predominant soil environment, the percentage of saprophagous animals was higher than carnivorous animals and herbivorous animals. The dynamics changes of sapro- phagous and carnivorous animals were distinctive, increasing from June to October, while the change of herbivorous animals was unremarkable.

关键词： soil animal Da Hinggan Mountains cold-temperate zone

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Recent advances in synthesis of organosilicons via radical strategies

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Chinese Chemical Letters 2021年第4期32卷 1280-1292页

作者： xueping zhang Jingkun Fang Chun Cai Guoping Lu School of Chemical Engineering Nanjing University of ScienceTechnologyNanjing 210094China

Organosilicon compounds play an important role in the fields of materials science,pharmacy,and organic *** development of effective approaches for the preparation of these compounds have also become a research focus in organic *** recent years,free radical synthesis of organosilicons has been vigorously developed,which generally has the advantages of milder synthesis conditions,higher yields and selectivity,and free of precious metal catalysts compared with traditional *** article reviews research progresses in the synthesis of organosilico n compounds by free radical pathways since *** most cases,the radical silylation is achieved based on the reaction of silyl radicals,which are triggered by four routes including peroxide,transition-metal-induced peroxide decomposition,alkali,*** alkyl radicals can also initiate the radical silylation for the generation of C(sp^(3))—Si bonds.

关键词： Organosilicon Radical silylation Single electron transfer Hydrogen atom transfer Photoredox Alkyl radical

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Transformation Method of Exterior Orientation Angular Elements Obtained via Position and Orientation System Under Gauss-Kruger Projection Coordinate System

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Geo-Spatial Information Science 2010年第3期13卷 157-165页

作者： YUAN Xiuxiao zhang xueping FU Jianhong School of Remote Sensing and Information Engineering Wuhan University 129 luoyu Road Wuhan 430079 China

Data obtained via airborne position and orientation system （POS） is in WGS 84 global geocentric reference frame, while the national coordinate reference system for topographic mapping in China is generally Gauss-Kruger projection coordinate system. Therefore, data obtained via a POS must be transformed to national coordinate system. Owing to the effects of earth curvature and me- ridian deviation, there are some errors in the process of angle transformation from roll, pitch, and heading （φ,θ,ψ） obtained directly via a POS to the attitude angles of images （φ,ω,κ） needed in photogrammetry. On the basis of effect theories of earth curvature and meridian deviation on exterior orientation angular elements of images, a method using a compensation matrix to correct the transformation errors from attitude angles obtained via the POS to exterior orientation angular elements of images is proposed in this paper. Moreover, the rigorous formula of the compensation matrix is deduced. Two sets of actual data obtained via a POS AV 510, which are different in scale and terrain, are selected and used to perform experiments. The empirical results not only indicate that the compensation matrix proposed in this paper is correct and practical but also show that transformation accuracy of exterior orientation angular elements obtained via the POS based on compensation matrix is relevant to the selection of vertical axis （a projection of central meridian） of Gauss-Kruger projection coordinate system; the proper vertical axis should be the Gauss-Kruger projection of the central meridian of projection zone in which the survey area locates. However, the transformation accuracy of exterior orientation angular elements is irrelevant to the choice of origin of coordinate system; it is appropriate that the origin of coordinate system locates at the center point of the survey area. Moreover, transformation accuracy of exterior orientation angular elements achieved based on the compensa- tion matri

关键词： position and orientation system (POS) exterior orientation elements of image earth curvature meridian deviation compensation matrix

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Directional Solidification Velocity of Undercooled Cu_(70)Ni_(30) Alloy Melt

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Journal of Materials Science & Technology 2001年第5期17卷 572-574页

作者： Research Notes JinfuLI xueping zhang and Yaohe ZHOU Gencang YANG School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The directional dendrite growth velocity in the Cu70Ni30 alloy melt undercooled by 90-185 K was measured by high speed cinematography, and compared with the calculated free dendrite growth velocity. It is found that at lower undercoolings the interaction between the adjacent directionally growing dendrites is weak, and there is not a marked difference between the velocity of the directionally growing dendrite and that of free dendrite. But with undercooling increasing, the interaction is enhanced due to the decrease of the primary arm spacing, which makes the velocity difference enlarge quickly.

关键词： Directional Solidification Velocity of Undercooled Cu Velocity Alloy Melt

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Measurement of Solid-liquid Equilibria in Quaternary System Li＋, K＋//SO42-, B4O72--H2O at 288 K

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Chemical Research in Chinese Universities 2016年第1期32卷 90-94页

作者： SANG Shihua FU Chao zhang Tingting zhang xueping XIAO Longjun College of Materials and Chemistry & Chemical Engineering Mineral Resources Chemistry Key Laboratory of Sichuan Higher Education Institutions Chengdu University of Technology Chengdu 610059 P. R. China

In order to utilize the brine resources in China, the solid-liquid equilibria in quaternary system Li＋, K＋//SO42 , B4O72 -H2O at 288 K was studied by the isothermal solution equilibrium method. Solubilities and densities of solutions were determined experimentally. According to the experimental data, the equilibrium phase diagrams, density-composition diagram and corresponding water content diagram of the quaternary system were plotted. Double salt KLiSO4 was found in the reciprocal quaternary system Li＋, K＋//SO42-, B4O72 -H2O at 288 K. The quaternary system has three invariant points, seven univariant curves and five fields of crystallization. The five crystalliza- tion regions correspond to Li2B4O7.3H2O, LizSO4-H2O, K2B4O7-4H2O, K2SO4 and KLiSO4, respectively. The crystal- lization field of salt LizB4O7 3H20 is the largest, whereas that of Li2SO4 H2O is the smallest. The experimental results show that LizSO4 H2O has a strong salting-out effect on other salts.

关键词： Solid-liquid equilibria Borate Double salt Salting-out effect

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Sonochemical synthesis and characterization of magnetic separable Fe_(3)O_(4)-TiO_(2)nanocomposites and their catalytic properties

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International Journal of Smart and Nano Materials 2010年第4期1卷 278-287页

作者： Wanquan Jiang xueping zhang Xinglong Gong Fangfang Yan Zhong zhang Department of Chemistry University of Science and Technology of China(USTC)Hefei 230026PR China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUSTCHefei 230027PR China National Center for Nanoscience and Technology Beijing 100080PR China

A novel sonochemical method is described for the preparation of Fe_(3)O_(4)–TiO_(2)photocatalysts in which nanocrystalline titanium dioxide particles are directly coated onto a magnetic *** Fe_(3)O_(4)nanoparticles were partially embedded in TiO_(2)***_(2)nanocrystallites were obtained by hydrolysis and condensation of titanium tetraisopropyl in the presence of ethanol and water under high-intensity ultrasound *** method is attractive since it eliminated the high-temperature heat treatment required in the conventional sol–gel method,which is important in transforming amorphous titanium dioxide into a photoactive crystalline *** comparison to other methods,the developed method is simple,mild,green and *** magnetization hysteresis loop for Fe_(3)O_(4)–TiO_(2)nanocomposites indicates that the hybrid catalyst shows superparamagnetic characteristics at room *** activity studies confirmed that the as-prepared nanocomposites have high photocatalytic ability toward the photodegradation of RhB ***,the photodecomposition rate decreases only slightly after six cycles of the photocatalysis ***,these Fe_(3)O_(4)–TiO_(2)nanocomposites can be served as an effective and conveniently recyclable photocatalyst.

关键词： sonochemical synthesis recyclable photocatalyst TiO_(2)nanocomposite rhodamine B degradation

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Relative Contributions of Spatial and Environmental Processes and Biotic Interactions in a Soil Collembolan Community

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Chinese Geographical Science 2015年第5期25卷 582-590页

作者： SHA Di GAO Meixiang SUN Xin WU Donghui zhang xueping Key Laboratory of Remote Sensing Monitoring of Geographic Environment College of Heilongjiang Province Harbin Normal University College of Geographical Science Harbin Normal University Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communities on a small scale. To evaluate the relative roles of biotic interactions and environmental and spatial processes in a soil collembolan community, a field experiment was carried out on a small scale(50 m) in the farmland ecosystem of the Sanjiang Plain, Northeast China. In August and October, 2011, we took 100 samples each month in a 50 m × 50 m plot using a spatially delimited sampling design. Variation partitioning was used to quantify the relative contributions of the spatial and environmental variables. A null model was selected to test for the non-randomness pattern of species co-occurrence and body size in assemblages of collembolans and to test whether the pattern observed was the result of environmental or biotic processes that structured the community on a small scale. The results showed that large variance was accounted for by spatial variables(18.99% in August and 21.83% in October, both were significant). There were relatively lower effects of environmental variation(3.56% in August and 1.45% in October, neither was significant), while the soil water content, soil p H and soybean height explained a significant portion of the variance that was observed in the spatial pattern of the collembolan community. Furthermore, the null model revealed more co-occurrence than expected by chance, suggesting that collembolan communities had a non-random co-occurrence pattern in both August and October. Additionally, environmental niche overlap and the body size ratio of co-occurrence showed that interspecific competition was not influential in collembolan community structuring. Considering all of the results together, the contributions of spatial and environmental processes were stronger than biotic interactions in the small-scale structuring of a soil c

关键词： spatial process environmental filtering biotic interactions variation partitioning small scale collembolan community

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Lignin-derived Zn single atom/N-codoped porous carbon forα-alkylation of aromatic ketones with alcohols via borrowing hydrogen strategy

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Nano Research 2022年第3期15卷 1874-1881页

作者： xueping zhang Guo-Ping Lu Kun Wang Yamei Lin Pengcheng Wang Wenbin Yi School of Chemistry and Chemical Engineering Nanjing University of Science&TechnologyXiaolingwei 200Nanjing 210094China School of Pharmaceutical Sciences Wenzhou Medical CollegeUniversity TownChashanWenzhou 325035China School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityWenyuanstreet 200Nanjing 210032China

A green and scalable strategy has been developed for the synthesis of lignin-derived Zn single atom/N-codoped porous carbon(LCN@Zn-SAC)containing similar ZnNx sites with carbonic *** catalyst exhibits superior activity on theα-alkylation of ketones with alcohols via borrowing hydrogen strategy(TON up to 15 h^(−1))than most of previously reported *** dehydrogenation of benzyl alcohol is the rate-determining step based on kinetic experiment *** to experimental and theoretical calculation results,Zn electron density is inversely proportional to reaction energy barriers,because Zn sites with less positive charge(ZnN_(4) and ZnN_(3)C)in Zn-SACs display better borrowing hydrogen ability than other Zn ***,this catalyst can be recycled by simple centrifugation,which can be reused at least 8 runs with no obvious lose in *** the best of our knowledge,this is the first example of non-noble metal-SAC-catalyzedα-alkylation via borrowing hydrogen strategy.

关键词： lignin zinc single atom catalyst N-doped porous carbon α-alkylation borrowing hydrogen

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Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China

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Chinese Geographical Science 2014年第3期24卷 339-347页

作者： LIN Lin GAO Meixiang LIU Dong zhang xueping WU Haitao WU Donghui Key Laboratory of Remote Sensing Monitoring of Geographic Environment College of Heilongjiang ProvinceHarbin Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale.

关键词： above-ground mite below-ground mite mite communities co-occurrence patterns interspecific competition species pairassociations

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