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Soil Aggregate Stability and Aggregate-Associated Carbon Under Different Tillage Systems in the North China Plain

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Journal of Integrative Agriculture 2013年第11期12卷 2114-2123页

作者： DU Zhang-liu REN Tu-sheng hu chun-sheng ZHANG Qing-zhong humberto Blanco-Canqui Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences College of Resources and Environmental Sciences China Agricultural University Center for Agricultural Resources Research Institute of Genetics and Development BiologyChinese Academy of Sciences Agricultural Research Center-Hays Kansas State University

The inlfuences of tillage systems on soil carbon （C） stocks have been studied extensively, but the distribution of soil C within aggregate fractions is not well understood. The objective of this study was to determine the inlfuences of various tillage systems on soil aggregation and aggregate-associated C under wheat （Triticum aestivum L.） and corn （Zea mays L.） double cropping systems in the North China Plain. The experiment was established in 2001, including four treatments：moldboard plow （MP） with residue （MP＋R） and without residue （MP-R）, rotary tillage with residue （RT）, and no-till with residue （NT）. In 2007 soil samples were collected from the 0-5, 5-10, and 10-20 cm depths, and were separated into four aggregate-size classes （〉2 000, 250-2 000, 53-250, and〈53 μm） by wet-sieving method. Aggregate-associated C was determined, and the relationships between total soil C concentration and aggregation-size fractions were examined. The results showed that NT and RT treatments signiifcantly increased the proportion of macroaggregate fractions （〉2 000 and 250-2 000 μm） compared with the MP-R and MP＋R treatments. Averaged across all depths, mean weight diameters of aggregates （MWD） in NT and RT were 47 and 20% higher than that in MP＋R. The concentration of bulk soil organic C was positively correlated with MWD （r=0.98; P=0.024） and macroaggregate fraction （r=0.96; P=0.036） in the 0-5 cm depth. In the 0-20 cm depth, comparing with MP＋R, total C occluded in the〉2 000 μm fraction was increased by 9 and 6%under NT and RT, respectively. We conclude that adoption of conservation tillage system, especially no-till, can increase soil macro-aggregation and total C accumulation in macroaggregates, which may improve soil C sequestration in the intensive agricultural region of the North China Plain.

关键词： tillage systems aggregate stability aggregate-associated C

Dating of the topmost terrace in the Jingxian Basin,Anhui Province:an indication of the establishment of the Qingyijiang River

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Journal of Mountain Science 2017年第3期14卷 549-557页

作者： hu chun-sheng hu Chen-qi LIU Shao-chen XU Guang-lai WU Li YANG Li-hui College of Territorial Resources and Tourism Anhui Normal UniversityWuhu 241000China Anhui Key Laboratory of Natural Disaster Process and Preventing and Controlling Wuhu 241000China

On the northern fringe of Mt. huangshan, many fiver terraces are developed at the junction between mountains and plains. The fiver terraces are most typical in the Jingxian Basin, Anhui Province, where the Qingyijiang River, one of the longest tributaries of the lower Yangtze River, developed three staircase terraces. The topmost terrace （i.e., the T3 terrace） tread is 38 - 39 m above fiver level, and the top of the gravels is generally covered by 3 - 10.9 m of red clay deposits. Systematic magnetostratigraphy and electron spin resonance dating are used to research the timing of the establishment of the Qingyijiang River. The main results show that the topmost terrace developed no later than 900 kyr ago and that the appearance of the Qingyijiang River occurred correspondingly at least before 900 kyr ago on the northern fringe of Mt. huangshan. In view of the almost synchronous age,the establishment of the Qingyijiang River was seemingly a response to the Mid-Pleistocene Revolution when the 100 kyr cycle commenced, and the Kunlun-huanghe movement during the early- middle Pleistocene transition. In addition, the establishment of the Qingyijiang River possibly reflected the birth of the modem Yangtze River to some degree. Therefore the timing of the formation of the Yangtze River is restricted to no later than 900 kyr ago based on the appearance of the Qingyijiang River .

关键词： Qingyijiang River Topmost terrace Magnetostratigraphy Electron Spin Resonance dating Establishment timing Jingxian Basin

Effect of Shock Absorbers’ Deformation on RLG’s Bias Temperature Modeling 26th

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Effect of Shock Absorbers’ Deformation on RLG’s Bias Tempe...

Natural ^(15)N Abundance in Winter Wheat Amended with Urea and Compost: A Long-Term Experiment

第26届中国控制与决策会议

作者： TAN Wen-feng hu chun-sheng WANG Xing-shu College of Optoelectronic Science and Engineering National University of Defense Technology

ISBN: (纸本)9781479937097

The deformation of shock absorbers has a great impact on gyro bias output during the system-level temperature modeling of gyro bias. In this paper, two ways of shock absorbers’ effect on gyro bias output are proposed: change of the Earth’s rotation component and slow movement of IMU apperceived by gyro. This paper analyzes the change of the Earth’s rotation component caused by the change of gyro’s sensitive axis. The effect of IMU’s slow movement is estimated. A method on how to place the gyro to weaken the impact of shock absorbers’ deformation is proposed. The effect of shock absorbers’ deformation on bias’ temperature model and accuracy of temperature compensation is analyzed through simulation.

关键词： shock absorbers bias temperature modeling

来源： cnki会议评论

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cnki会议

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Pedosphere 2013年第6期23卷 835-843页

作者： ZHOU Wei hu chun-sheng LI Ji P.CHRISTIE HE Xin-hua JU Xiao-Tang Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of Sciences University of Chinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University Agri-Environment Branch Agri-Food and Biosciences Institute Northern Research Station USDA Forest Service

We investigated 15N abundance （δ15N） of winter wheat （Triticum aestivum cv. Jinmai 1） plants and soil at different growth stages in a field with a 13-year fertilization history of urea and compost, to determine whether or not the δ15N of plant parts can be used as an indicator of organic amendment with compost. Plant parts （roots, leaves, stems and grains） and soil were sampled at re-greening, jointing, grain filling and mature growth stages of winter wheat. There were significant differences between the urea and compost treatments in 815N of whole plants, plant parts and soil over the whole growing season. Determination of the δ15N of plant parts was more convenient than that of whole plant to distinguish between the application of organic amendment and synthetic N fertilizer.

关键词： detection growth stages natural δ15N organic food tissue

Yield and quality of maize stover: Variation among cultivars and effects of N fertilization

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Journal of Integrative Agriculture 2015年第8期14卷 1581-1587页

作者： LIANG Ming-yuan WANG Gui-yan LIANG Wei-li SHI Peng-fei DANG Jing SUI Peng hu chun-sheng Faculty of Agronomy Agricultural University of Hebei School of Agronomy and Biotechnology China Agricultural University Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences

Biomass yields and concentrations of crude protein（CP）, ether extract（EE）, neutral detergent fiber（NDF）, acid detergent fiber（ADF）, and crude fiber（CF） were analyzed for five cultivars of summer-sown maize（Zea mays L.） stover grown in field trials at three rates of N fertilization, and sampled immediately after grain *** results revealed differences in yields and concentrations of nutrients according to stalk height and hence harvest portion among the cultivars.N application greatly increased biomass yield and CP, especially in upper stalks and to a lesser extent, *** of NDF and ADF decreased as N rate *** results show that stovers from all local popular maize cultivars are suitable as animal fodder and that moderate N application improves feed quality of stover.

关键词： maize stover fodder quality yield cultivar nitrogen

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岩棉棉包码垛机器人的设计

制造业自动化 2024年第3期46卷 162-166页

作者：魏红星胡春生李国利闫小鹏张文雪宁夏大学机械工程学院银川750021

针对传统岩棉棉包需要人工码垛的问题,设计出适合多规格岩棉棉包码垛的机器设备,岩棉码垛机器人由称重计数模块、翻转模块、上料模块、码垛机械手、下料模块和其他辅助装置组成,可以实现岩棉棉包搬运、码垛、称重、计数等过程的自动化作... 详细信息

针对传统岩棉棉包需要人工码垛的问题,设计出适合多规格岩棉棉包码垛的机器设备,岩棉码垛机器人由称重计数模块、翻转模块、上料模块、码垛机械手、下料模块和其他辅助装置组成,可以实现岩棉棉包搬运、码垛、称重、计数等过程的自动化作业,可以解决传统人工码垛生产效率低、身体损伤大、重复工作多、生产安全性差等问题。具有生产效率高、兼容性强、维护保养便捷等优点,为岩棉棉包实际码垛生产提供技术参考。

关键词：岩棉码垛自动化

Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： Jia-Jia Wu Fei Wang Peng-Qi Wan Li Pan chun-sheng Xiao Zhe Ma Yue-sheng Li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-sheng Xu chun-Tao Lin Na Wang Jing-Ye Xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan Feng Jian Zhang Hong-wu Tang Yang Xiao sheng Chen chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM