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Scale Effects of Geographical Soil Datasets on Soil Carbon Estimation in Louisiana,USA:A Comparison of STATSGO and SSURGO

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Pedosphere 2011年第4期21卷 491-501页

作者： b. zhong Y. J. XU School of Renewable Natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carbon （SOC） pools and fluxes bears large uncertainties because SOC stocks vary greatly over geographical space and through time. Although development of the U.S. Soil Survey Geographic Database （SSURGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved substantial government funds and coordinated network efforts, very few studies have utilized it for soil carbon assessment at the large landscape scale. The objectives of this study were to 1） compare estimates in soil organic matter among SSURGO, the State Soil Geographic Database （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on SOC estimation by SSURGO and STATSGO; 3） quantify spatial differences in SOC estimation between SSURGO and STATSCO, specifically for the state of Louisiana; and 4） assess scale effects on soil organic carbon density （SOCD） estimates from a soil map unit to a watershed and a river basin scale. SOC was estimated using soil attributes of SSURGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and bulk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of SOC and SOM among the datasets. There were positive relations of SOC estimates between SSURGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the SOC estimated by STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSURGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river basin scales. Compared with the referenced field measurements, the estimates in SOM by SSURGO showed a closer match than those of STATSCO, indicating that the former was more accurate than the latter in SOC estimation, both in spatial and temporal resoluti

关键词： carbon accounting climate change GIS soil organic carbon soil organic matter

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Assessment of Defects and Collapsed Sites in Self-Assembled Alkanethiol Monolayer on Gold by Cyclic Voltammetry and ***

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Chinese Chemical Letters 1998年第12期9卷 0-0,0-0页

作者： Diao, P Jiang, DL Cui, XL Gu, DP Tong, RT zhong, b Chinese Acad Sci Inst Coal Chem Taiyuan 030001 Peoples R China Hebei Teachers Univ Dept Chem Shijiazhuang 050016 Peoples R China

Self-assembly of octadecyl mercaptan on gold was investigated by cyclic voltammetry(CV) and electrochemical impedance spectroscopy (EIS). Results of CV experiments show thatthere are no structUral defects exposed directly to the redox couple in solution, but EISexperiments indicate that collapsed sites exist in the monolayer. A method to estimate the degree ofdisorder in the Au/thiol monolayer surface is proposed by using admittance plane plot.

关键词： Self-assembled monolayer cyclic voltammetry a.c. impedance ideally polarizable electrode surface roughness

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THEORETICAL INVESTIGATION ON bY-ONLY-CURRENT ELECTROMAGNETIC SEPARATION OF INCLUSION FROM MOLTEN METALS

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Acta Metallurgica Sinica(English Letters) 2002年第5期15卷 416-424页

作者： b. W. Zhang, Z.M. Ren , Y.b. zhong, K. Deng and K.D. XuShanghai Enhanced Laboratory of Metallurgy,Shanghai University, Shanghai 200072, China Enhanced Lab. of Metall. Shanghai Univ. Shanghai 200072 China

The electromagnetic field under applied AC and DC current in round and rectangular pipe was systematically investigated, then a concept of 'equivalent current density' was proposed for evaluating the inhomogeneous electromagnetic pinch force, and the mono-component removal efficiency and the overall removal efficiency of inclusion were formulated. It is founded that flat pipe is superior to round pipe for the electromagnetic removal of inclusion, and DC current can get a higher removal efficiency than A C current due to absence of skin phenomenon. Under usual condition, a removal efficiency of 52% for 10μm inclusion or more than 92% for 20μm inclusion can be achieved by imposing a current density of 3×106A/m2 in a flat pipe.

关键词： inclusion electromagnetic separation efficiency of removal equivalent current density

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NON-INERTIAL MULTIbLOCK NAVIER-STOKES CALCULATION FOR HOVERING ROTOR FLOWFIELDS USING HIGH ORDER APPROXIMATE RIEMANN SOLVER

NON-INERTIAL MULTIBLOCK NAVIER-STOKES CALCULATION FOR HOVERI...

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第四届亚洲计算流体力学会议

作者： b.zhong N.Qin Centre for Computational Aerodynamics Cranfield College of Aeronautics bedford MK43 OAL UK Centre for Computational Aerodynamics Cranfield College of Aeronautics bedford MK43 OAL UK

＜正＞ A three dimensional Navier-Stokes solver is developed for calculating the hovering rotor flowfield using Osher’s approximate Riemann solver. The Navier-Stokes equations are recast in the attached blade relative system using relative flow velocities as variables. Multiblock techniques are used to obtain the flexibility for quality grid generation. A modified MUSCL scheme is found useful to alleviate the inaccuracy in the discretisation of the relative variable formulation. The calculations are performed for a two-bladed model rotor on O-O and C-H cylindrical grids respectively. The difficulty and suitability of different grid topologies for capturing the tip vortex are illustrated. The differences between Euler and Navier-Stokes solutions are revealed.

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EFFECT OF AUSTENITIZING TEMPERATURE ON STRUCTURE AND MECHANICAL PROPERTIES OF 23NiCo ALLOY

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 621-625页

作者： P. zhong, b. Ling and b. Z. Gu beijing Institute of Aeronautical Materials,beijing 100095 ,China

Effectof the austenitizing temperature on the microstructure, strength, and toughness of23 NiCo alloy wasstudied . With increasing theaustenitizingtemperature,the reductionsin strength and hardness are probably caused by the coarsening of M2 Ccarbides. The use of higheraustenitizingtemperatureresultedinimproved impacttoughness duetothe dissolutionof undissolved,( CrFeMo)23 C6 carbides. For austenitizingtemperaturesgreaterthan 950 ℃ resultedinthelossofimpacttoughness. Astheaustenitizingtemperatureisincreasedto1050 ℃impacttoughnesslevelsarereduced on an averageby53 J/cm2 .Examination ofthefrac turesurfaceofimpacttoughnessspecimens viascanningelectron microscopy ( SEM) revealedthataustenitizing at1050 ℃and aged at482℃wasintergranularfracture .It wassuggested thatthisgrain boundary embrittlement wastheresultofthe formation of cementite particlesduring aging.

关键词： secondary hardening 23 NiCo alloy austenitizingtemperature

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Phylogenetic relationship and morphological evolution in the subfamily Limenitidinae(Lepidoptera:Nymphalidae)

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Progress in Natural Science:Materials International 2008年第11期18卷 1357-1364页

作者： Min Zhang~a Yang zhong~b Tianwen Cao~c Yupeng Geng~b Yuan Zhang~b Ke Jin~b Zhumei Ren~a Rui Zhang~a Yaping Guo~a Enbo Ma~(a,*) a Research Institute of Applied biology and College of Life Science and Technology,Shanxi University,Taiyuan,Shanxi 030006,China b School of Life Sciences,Fudan University Shanghai 200433,China c Institute of Plant Protection,Shanxi Academy of Agricultural Science,Taiyuan 030031,China Research Institute of Applied biology and College of Life Science and Technology Shanxi University Taiyuan Shanxi 030006 China School of Life Sciences Fudan University Shanghai 200433 China Institute of Plant Protection Shanxi Academy of Agricultural Science Taiyuan 030031 China

The mitochondrial cytochrome oxidase subunit I(COI)gene and the nuclear elongation factor 1α(EF-1α)gene were sequenced from 29 species of Nymphalidae(Nymphalidae,Lepidoptera).Phylogenetic trees were constructed based on the sequences determined from the 29 species and sequences of other 36 species deposited in Genbank using the neighbor-joining(N J),maximum likelihood(ML)and bayesian methods with Libythea celtis(Libytheinae)as the *** phylogenetic trees indicated four major *** A includes three subfamilies:Apaturinae,Nymphalinae,and Limenitidinae,excluding the tribe Limenitidini;Clade b includes the subfam- ilies Heliconiinae and the tribe Limenitidini;Clade C includes Satyrinae,Calinaginae,Charaxinae and Morphinae;and Clade D includes subfamily *** study suggested that the tribes Pseudergolini,biblidini,Limenitidini and Cyrestidini should be considered as subfamilies and confirmed the interspecific relationships within the subfamily Pseudergolinae,namely Amnosia +(Pseudergolis +(Stibo- chiona + Dichorragia)).We then mapped three morphological characters(spot of anal angle,eyespots,and process from outer margin of hind wing)onto the phylogenetic tree constructed by ML analysis using the combined sequence *** on this the evolutionary patterns of these morphological characters were identifed,they indicated that the three characters evolved repeatedly in the family Nymphalidae.

关键词： Nymphalidae Limenitidinae Mitochondrial DNA cytochrome oxidase subunitⅠgene(COI) Nuclear elongation factor 1αgene(EF-1α) Molecular phylogeny Character evolution

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压力型体制与中国官员的降职风险:基于事件史分析的视角

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南方经济 2016年第10期45卷 54-74页

作者：钟灵娜庞保庆上海财经大学公共经济与管理学院上海大学社会学院

以往对官员的研究主要集中在讨论影响官员晋升的因素上,文章利用事件史分析的方法讨论官员的降职风险。利用2000-2012年间市委书记的数据发现,首先,官员年龄与是否离任密切相关,特别年轻与特别年长的官员都面临较大的降职风险;其次,官... 详细信息

以往对官员的研究主要集中在讨论影响官员晋升的因素上,文章利用事件史分析的方法讨论官员的降职风险。利用2000-2012年间市委书记的数据发现,首先,官员年龄与是否离任密切相关,特别年轻与特别年长的官员都面临较大的降职风险;其次,官员在任期间的经济绩效对降职风险影响显著,并且这一影响与官员的政治关系密切相关。被上级下派到地方加以培养锻炼的官员所面临的降职压力较小,而其他官员则需要努力提升经济绩效才能确保自己不会被降职淘汰。此外,文章还发现晋升风险概率与经济绩效之间并不存在类似的关系,说明晋升的机制可能更为复杂。

关键词：官员降职事件史分析政治关系压力型体制

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Immobilized enzyme reactors in HPLC and its application in inhibitor screening:A review

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Journal of Pharmaceutical Analysis 2012年第2期2卷 83-89页

作者： Si-Meng Fang a,Hai-Na Wang a,zhong-Xi Zhao b,Wei-Hong Wang a,n a School of Pharmaceutical Sciences,Shandong University,Ji’nan,China b School of Pharmaceutical Sciences and Center for Pharmaceutical Research & Drug Delivery Systems,Shandong University,Ji’nan,China School of Pharmaceutical Sciences Shandong University Ji'nan China. School of Pharmaceutical Sciences and Center for Pharmaceutical Research & Drug Delivery Systems Shandong University Ji'nan China.

This paper sets out to summarize the literatures based on immobilized enzyme bio-chromatography and its application in inhibitors screening in the last *** order to screen enzyme inhibitors from a mass of compounds in preliminary screening,multi-pore materials with good biocompatibility are used for the supports of immobilizing enzymes,and then the immobilized enzyme reactor applied as the immobilized enzyme stationary phase in ***,a technology platform of high throughput screening is gradually established to screen the enzyme inhibitors as new anti-tumor ***,we briefly summarize the selective methods of supports,immobilization techniques,co-immobilized enzymes system and the screening model.

关键词： Immobilized enzyme reactors (IMERs) Molecular bio-chromatography Screening enzyme inhibitors

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CO2 Adsorptions of N-rich Metal-organic Frameworks:Theoretical Prediction and Experimental Studies

CO2 Adsorptions of N-rich Metal-organic Frameworks:Theoretic...

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中国化学会第六届全国结构化学学术会议

作者： Jun-Sheng Qin,~a Ya-Qian Lan~b and zhong-Min Su~(*a,b) a State Key Laboratory of Supramolecular Structure and Materials,Jilin University, Changchun 130012

＜正＞b Faculty of Chemistry,Northeast Normal University,Changchun 130024 Metal-organic frameworks（MOFs） have drawn considerable attention in recent years and are being evaluated for diverse potential applications.1,2 Remarkably,the permanent porosity,tunable pore sizes and shape,as well as exceptional thermal and chemical stability of MOFs permit their potential applications in gas adsorption and selective ***,great efforts have been devoted to developing versatile

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THE COMPUTATION AND EXPERIMENT ANALYSIS OF ELECTROMAGNETIC CONTINUOUS CASTING WITH SOFT-CONTACTED MOULD

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 708-714页

作者： K. Deng, Z.M. Ren, Y.b. zhong, G.C. Jiang and S.M.Hu 1) School of Materials, Shanghai University, Shanghai 200072, China 2) Shanghai bAOSTEEL Group, Shanghai 200941, China

In this paper, coupling the quasi-3D numerical simulation of electromagnetic field and the experiments of continuous casting with soft-contacted mould with some metals such as tin, aluminum, copper and steel, the electromagnetic characteristics of continuous casting with soft-contacted mould is analyzed. It is shown that the electromagnetic pressure on the surface of billet is increasing with the rising of power frequency as a logarithmically parabolic function, with that of electric conductivity of billet as a power junction, and with that of the current in inductor as a parabolic junction.

关键词： continuous casting (CC) electromagnetic continuous casting (EMC) soft-contacted mould electromagnetic field (EMF) numerical simulation.

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