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numerical analysis and centrifugal modeling of LnAPLs transport in subsurface system

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Progress in natural Science:Materials International 2006年第4期16卷 416-424页

作者： LO I.M.C. MEEGODA j.n. Department of Civil Engineering Hong Kong University of Science and Technology Hong Kong SARChina Department of Civil and Environmental Engineering new jersey Institute of Technology USA

The transport of non-aqueous phase liquids (nAPLs) in unsaturated soils and groundwater is an important research topic in geo-environmental engineering. In this paper, the mechanism of light nAPLs (LnAPLs) transport in subsurface system is briefly introduced, and the mass transport equations, fluid flow equations, and the constitutive model of relative permeability - saturation - capillary pressure are discussed. Then the numerical method is introduced to simulate the multiphase flow problems in porous media, and the tempospatial distribution of LnAPLs is obtained. Moreover, different boundary conditions are employed in numerical simulation to investigate its effect on transport behavior. To verify the numerical data, centrifugal tests are conducted to model the LnAPLs migration in unsaturated soils and groundwater. The calculation results are agreeable with the experimental findings of centrifugal modeling, which indicates that LnAPLs from leaking point move downwards due to gravity force, and form a high concentration zone above the capillary fringe, and then spread out laterally along the groundwater table. Some LnAPL enters groundwater system to further migrate. The combination of numerical simulation and centrifuge modeling can be a useful means to study the transport behavior of LnAPLs in subsurface system.

关键词： geo-environmental engineering subsurface contamination multiphase flow light non-aqueous phase liquids (LnAPLs) centrifugal modeling technique numerical simulation.

new multi-phonon gamma vibrational bands in A～110 neutron-rich nuclei

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 44-48页

作者： HAMILTOn j H RAMAYYA A V rasmussen j O HWAnG j K YEOH E Y Department of Physics Vanderbilt University Nashville TN 37235 USA Lawrence Berkeley national Laboratory Berkeley CA 94720 USA Department of Physics Tsinghua University Beijing 100084 China

The high spin states of neutron-rich 103nb, 107Tc and 109Tc nuclei in A^110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified. The two-phonon bands are first observed in odd-Z nuclei. The characteristics for these band structures have been discussed.

关键词： high spin states neutron-rich nucleus γ-vibrational bands

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Preface

Preface

Towards fully automated GW band structure calculations:What we can learn from 60.000 self-energy evaluationsTowards fully automated GW band structure calculations:What we can learn from 60.000 self-energy evaluations

第一届工程科学与力学中的计算方法国际会议

作者： j.n. Reddy General Co-Chairman

＜正＞This first International Conference on Enhancement and Promotion of Computational Methods in Engineering Science and Mechanics （CMESM 2006） is intended to provide an international forum for presentation of recent advances on various aspects of theories, analyses, and companion experiments and designs involving numerical simulations, multiscale modeling methods for materials, and topics in simulation-based computational engineering science. In particular, it reflects the state-of-the-art in computational methods and engineering applications characterized by multiscales and multiphysics approaches.

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来源： cnki会议评论

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npj Computational Materials 2021年第1期7卷 189-197页

作者： Asbjørn rasmussen Thorsten Deilmann Kristian SThygesen CAMD Department of PhysicsTechnical University of Denmark2800 Kongens LyngbyDenmark Center for nanostructured Graphene(CnG) Technical University of Denmark2800 Kongens LyngbyDenmark Institut für Festkörpertheorie Westfälische Wilhelms-Universität Münster48149 MünsterGermany

We analyze a data set comprising 370 GW band structures of two-dimensional(2D)materials covering 14 different crystal structures and 52 chemical *** band structures contain a total of 61716 quasiparticle(QP)energies obtained from plane-wavebased one-shot G0W0@PBE calculations with full frequency *** investigate the distribution of key quantities,like the QP self-energy corrections and QP weights,and explore their dependence on chemical composition and magnetic *** linear QP approximation is identified as a significant error source and we propose schemes for controlling and drastically reducing this error at low computational *** analyze the reliability of the 1/n basis set extrapolation and find that is well-founded with a narrow distribution of coefficients of determination(r^(2))peaked very close to ***,we explore the accuracy of the scissors operator approximation and conclude that its validity is very *** work represents a step towards the development of automatized workflows for high-throughput G0W0 band structure calculations for solids.

关键词： structure approximation weights

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亚洲金融危机对农产品市场的影响

中国农村经济 1998年第12期 72-75页

作者： j.n.格林菲尔德联合国粮农组织农业部农村经济研究中心

本文对亚洲金融危机的某些影响进行述评，重点分析对国际农产品价格的影响、对亚洲某些国家供求形势的影响以及对食品安全的影响。一、基本判断１．虽然亚洲金融危机始于１９９７年夏天，但至今它对宏观经济仍然产生着影响。亚洲金融危... 详细信息

本文对亚洲金融危机的某些影响进行述评，重点分析对国际农产品价格的影响、对亚洲某些国家供求形势的影响以及对食品安全的影响。一、基本判断１．虽然亚洲金融危机始于１９９７年夏天，但至今它对宏观经济仍然产生着影响。亚洲金融危机的基本特征是股票值大幅度下跌，货...

关键词：亚洲地区金融危机农产品市场影响

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列宁著作在法国的传播

马克思主义与现实 2014年第5期66卷 43-47页

作者： j.n.迪康热赵超法国鲁昂大学历史系中央编译局信息部

列宁著作在法国的传播真正始于第一次世界大战后,在法共的推动下,列宁著作在法国的出版工作逐渐受到重视,有计划、有系统地开展起来,发行量也大幅增加,20世纪60—80年代达到巅峰期。随后由于受到前苏联模式危机的影响,迅速进入衰落期。... 详细信息

列宁著作在法国的传播真正始于第一次世界大战后,在法共的推动下,列宁著作在法国的出版工作逐渐受到重视,有计划、有系统地开展起来,发行量也大幅增加,20世纪60—80年代达到巅峰期。随后由于受到前苏联模式危机的影响,迅速进入衰落期。列宁著作在法国的传播过程经历了几个重要的阶段,各个阶段受到当时政治和社会环境的影响,呈现出不同的特点。与此同时,来自法国本土、前苏联、中国、阿尔巴尼亚等国家和地区的法文版本汇聚在一起,对列宁思想在法国的传播提供了多元的角度和丰富的资源,也成为侧面反映当时国际政治局势的要素之一。

关键词：列宁著作法文版法国传播史

Instantaneous frequency and wave mode identification in a magnetosheath using few spatial points

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Chinese Physics B 2013年第8期22卷 496-501页

作者： nathaniel E U Beloff n George n j Department of Physics Akwa Ibom State UniversityNigeria University of Sussex Brighton UK

Observational data such as those obtained from the magnetosheath in the downstream of Earth＇s bow shock have waveforms that differ from those of sinusoidal signals. In practice, they are not even aggregates of sinusoidal signals. Therefore, the frequency decomposition for the data requires technique that will account for the time-varying features of the data that will lead to deduction of physical meaning of the observations. The combination of empirical mode decompo- sition （EMD） and Hilbert transform has been used for extracting the various contributing oscillatory modes （EMDs） and the instantaneous frequency determination （Hilbert transform） of every physically meaningful mode called intrinsic mode func- tion （IMF）. The resulting instantaneous frequencies are used to determine instantaneous wave vectors. The combination of the instantaneous frequencies and wave vectors is useful in the identification of wave modes based on the characteristics of the waves. The results show that EMD-Hilbert can be more reliable than simple Hilbert transform alone.

关键词： EMD-Hilbert transform instantaneous frequency and wave vector

On Integrable Roots in Split Lie Triple Systems

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Acta Mathematica Sinica,English Series 2009年第11期25卷 1759-1774页

作者： A.j.CALDERón MARTín Departamento de Matemáticas Universidad de Cádiz

We focus on the notion of an integrable root in the framework of split Lie triple systems T with a coherent 0-root space. As a main result, it is shown that if T has all its nonzero roots integrable, then its standard embedding is a split Lie algebra having all its nonzero roots integrable. As a consequence, a local finiteness theorem for split Lie triple systems, saying that whenever all nonzero roots of T are integrable then T is locally finite, is stated. Finally, a classification theorem for split simple Lie triple systems having all its nonzero roots integrable is given.

关键词： Lie triple system root split Lie algebra classification theory

Assessing soil thickness in a black soil watershed in northeast China using random forest and field observations

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International Soil and Water Conservation Research 2021年第1期9卷 49-57页

作者： Shuai Zhang Gang Liu Shuli Chen Craig rasmussen Baoyuan Liu Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China Department of Environmental Science University of Arizona1177 E.Fourth StTucsonAZ 85721-0038USA

Soil thickness determines the soil productivity in the black soil region of northeast China,which is important for national food *** information on the spatial variation of black soil thickness is *** this paper,we propose a model framework for spatial estimation of the black soil thickness at the watershed scale by integrating field observations,unmanned aerial vehicle variations of topography,and satellite variations of vegetation with the aid of random *** sampled 141 sample profiles over a watershed and identified the black soil thickness based on indices of the mollic *** variables were derived from a digital elevation model and vegetation variables were derived from Landsat 8 *** forest was used to determine the relationship between black soil thickness and environmental *** resulting model explained 61%of the black soil thickness spatial variation,which was more than twice that of traditional interpolation methods(ordinary kriging,universal kriging and inverse distance weighting).Topographic variables contributed the most toward explaining the thickness,followed by vegetation *** black soil thickness over the watershed had a clear catenary soil pattern,with thickest black soil in the low depositional areas and thinnest at the higher elevations that drain into the low *** proposed model framework will improve estimates of soil thickness in the region of our study.

关键词： Soil thickness Random forest Black soils northeast China Soil geomorphology