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Environmental Fate of Petroleum Hydrocarbons in Soil:Review of Multiphase Transport,Mass Transfer,and Natural Attenuation Processes

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Pedosphere 2018年第6期28卷 833-847页

作者： Maria BalSEIRO-ROMERO Carmen MONTERROSO juan j.CASARES Department of Chemical Engineering Centre for Research in Environmental Technologies (CRETUS)Universidade de Santiago de CompostelaSantiago de Compostela 15782(Spain) Department of Soil Science and Agricultural Chemistry Centre for Research in Environmental Technologies (CRETUS)Unzversidade de Santiago de CompostelaSantiago de Compostela 15782(Spain)

The increasing use of petroleum-derived fuels over the last few decades has subsequently augmented the risk of spills in the environment. Soil pollution with petroleum hydrocarbons(principally caused by leaks in pipelines and underground storage tanks) is one of the major sources of soil degradation. Once in soil, fuel hydrocarbons suffer from a wide variety of multiphase processes including transport(advection, diffusion, and dispersion) among and within phases(aqueous and non-aqueous liquid, gas, and soil solids), mass transfer among phases(volatilization, sorption, and solution), and other natural attenuation processes, such as biodegradation and plant uptake and metabolism. This review identifies and describes the major processes occurring in soil that have a significant influence on the environmental fate of petroleum hydrocarbons. The definition of the processes involved in pollutant migration and distribution in soil and the formulation of adequate equations using accurate parameters(e.g., diffusion coefficients, velocity of advective flows, and mass transfer coefficients) will allow prediction of the final fate of soil pollutants. In addition to transport and mass transfer processes,which are more widely studied, the incorporation of attenuation mechanisms driven by microorganisms and plants is essential to predict the final concentration of the pollutants in the whole multiphase scenario. This work underlines the importance of the determination of accurate parameters through the performance of laboratory and/or field-scale experiments to develop precise pollutant migration models.

关键词： degradation fuel-derived pollutants modelling multiphase non-aqueous phase liquid soil pollution soil processes sorption

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Clinical Management of Mid-Root Fracture in Maxillary Central Incisors:Case Reports

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International journal of Oral Science 2010年第4期2卷 215-221页

作者： Deepak j. Parekh Ramarao Sathyanarayanan Mangala Tiptur Manjunath Department of Conservative Dentistry and Endodontics Bapuji Dental College and Hospital

Management of mid-root fractures presents a formidable challenge for clinicians because of the difficulty of achieving a stable reunion of fracture fragments. This article presents two varied treatment options for mid-root fractures. A 15-year-old female reported an impact injury to the maxillary anterior teeth 2 days after its occurrence. Clinically,the maxillary left central incisor was palatally-extruded with a negative vitality response and radiographic evidence of an oblique fracture at the middle third of the root. An endodontic implant was employed which utilized an open technique and has been on follow-up for ten months. A 32-year-old male reported an injury,which resulted in a mobile maxillary right central incisor,three months after its occurrence. Through clinical and radiographic means,a discolored,extruded,and non-vital maxillary right central incisor with an oblique root fracture at the alveolar-crest level was observed. Exploratory surgery was performed; an apical barrier was created with a mineral trioxide aggregate and obturated with gutta percha. The fragments were stabilized with a fiber post and patient has been on follow-up for five months. Short-term follow-up for both of the cases showed promising results both clinically and radiographically.

关键词： endodontic implant fiber post maxillary central incisor root fracture titanium min screw

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Application of Advection-Diffusion Routing Model to Flood Wave Propagation： A Case Study on Big Piney River, Missouri USA

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journal of Earth Science 2016年第1期27卷 9-14页

作者： Yang Yang Theodore A. Endreny David j. Nowak USDA Forest Service Northern Research Station & the Davey Institute Syracuse NY 13210 USA Environmental Resource Engineering SUNY ESF Syracuse NY 132 10 USA USDA Forest Service Northern Research Station Syracuse NY 13210 USA

Flood wave propagation modeling is of critical importance to advancing water resources management and protecting human life and property. In this study, we investigated how the advection-diffusion routing model performed in flood wave propagation on a 16 km long downstream section of the Big Piney River, MO. Model performance was based on gaging station data at the upstream and downstream cross sections. We demonstrated with advection-diffusion theory that for small differences in watershed drainage area between the two river cross sections, inflow along the reach mainly contributes to the downstream hydrograph＇s rising limb and not to the falling limb. The downstream hydrograph＇s falling limb is primarily determined by the propagated flood wave originating at the upstream cross section. This research suggests the parameter for the advectiondiffusion routing model can be calibrated by fitting the hydrograph falling limb. Application of the advection diffusion model to the flood wave of january 29, 2013 supports our theoretical finding that the propagated flood wave determines the downstream cross section falling limb, and the model has good performance in our test examples.

关键词： advection-diffusion equation hydrograph flood wave propagation recession limb.

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A Raman laser system for multi-wavelength satellite laser ranging

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 737-743页

作者： K.Hamal I.Prochazka j.Blazej Czech Technical University in Prague CzechCzech Technical University in PragueCzechCzech Technical University in PragueCzech

In order to develop a laser system for multi-wavelength satellite laser ranging,the joint group of the Shanghai Astronomical Observatory and the Czech Technical University has studied the conversion efficiency of the Raman-shifting beam and its spatial *** adopted a 0.53 μm laser with pulse width of 35 ps and peak energy of 35 mj,the second harmonic of a Nd:YAG actively and passively mode-locked laser,to pump a one-meter-long Raman tube which is full of H2 with high pressure at the Prague-based *** get the first Stokes laser (0.68 μm):7 mj (single pulse) with beam divergence of 40" (arcsecond) and spatial wobbling of less than 4";and the first anti-Stokes laser (0.43 μm):2 mj (single pulse) with divergence of 56" and spatial wobbling of less than 4".The emitting beam from the Raman cell also includes 0.53μm:10 mj (single pulse) with divergence of 40" and spatial wobbling of less than 7".According to the radar link equation and based on the above on the above obtained multi-wavelength’s energy,we can estimate the detection probabilities for three colors *** is shown by the result that the developed multi-wavelength Raman laser system has the capability of satellite *** Raman laser system will be installed at the laser station in Shanghai Astronomical Observatory to research the multi-wavelength satellite laser ranging.

关键词： multi-wavelength satellite laser ranging, Raman laser, atmosphere correction, detection probability.

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Preservation of a Paleoproterozoic rifted margin in the Himalaya:Insight from the Ulleri-Phaplu-Melung orthogneiss

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Geoscience Frontiers 2019年第3期10卷 873-883页

作者： K.Larson S.Piercey j.Cottle Earth Environmental and Geographical Sciences IKBSAS University of British Columbia Department of Earth Sciences Memorial University of Newfoundland Department of Earth Science University of CaliforniaSanta Barbara

Orthogneiss within the Paleoproterozoic strata of Lesser Himalayan sequence across the Himalaya has been variably linked to development in a continental arc setting, Indian basement, or a continental *** whole rock and trace element geochemical data and U/Pb zircon geochronology indicate that the granitoid protoliths to these rocks were derived from upper crustal sources in the Paleoproterozoic and have within-plate, A-type affinities. This is consistent with their generation in a rifted margin and is compatible with paleogeographic reconstructions that indicate an open boundary for present-day northern India in the Paleoproterozoic.

关键词： Himalaya Geochemistry Paleogeography Rifting Geochronology

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Symplectic feedback using Hamiltonian Lie algebra and its applications to an inverted pendulum

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控制理论与应用（英文版） 2013年第2期11卷 275-281页

作者： j. Lorca ESPIRO C. Munoz POBLETE Departamento de Ciencias Fisicas Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile Departamento de Ingenieria Electrica Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile

From the symplectic representation of an autonomous nonlinear dynamical system with holonomic con- straints, i.e., those that can be represented through a symplectic form derived from a Hamiltonian, we present a new proof on the realization of the symplectic feedback action, which has several theoretical advantages in demonstrating the uniqueness and existence of this type of solution. also, we propose a technique based on the interpretation, construction and character- ization of the pull-back differential on the symplectic manifold as a member of a one-parameter Lie group. This allows one to synthesize the control law that governs a certain system to achieve a desired behavior; and the method developed from this is applied to a classical system such as the inverted pendulum.

关键词： Hamiltonian systems Symplectic structures Lie algebra Nonlinear dynamical systems Geometric con-trol

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U（5）-O（6） Phase Transition in the SD-Pair Shell Model

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Chinese Physics Letters 2008年第7期25卷 2432-2435页

作者：王芙蓉刘霖罗延安潘峰 DRAAYER j.P Department of Physics Tianjin Radio and Television University Tianjin 300191 Department of Physics Nankai University Tianjin 300071 Department of Physics: Liaoning Normal University -Dalian 116029 Department of Physics and Astronomy Louisiana State University Baton Rouge LA 70803 USA

U（5）-0（6） transitional behaviour in the SD-palr shell model is studied. The results show that the U（5）-O（6） transitional patterns of the interacting boson model can be reproduced in the S D-palr shell model ap... 详细信息

关键词： INTERACTING-BOSON MODEL

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Micropatterning of Superhydrophobic Silicone Nanofilaments by a Near-Ultraviolet Nd:YAG Laser

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Nano Research 2010年第12期3卷 889-894页

作者： Ana Stojanovic Georg R.j.Artus Stefan Seeger Institute of Physical Chemistry University of ZurichWinterthurerstrasse 1908057 ZürichSwitzerland

We demonstrate that a recently developed coating composed of superhydrophobic silicone nanofilaments can be selectively functionalized to yield well defined micron-scale patterns of contrasting wettabilities(superhydrophobic/hydrophilic and amphiphobic/amphiphilic).Nanofilament ablation was performed using a near-ultraviolet(UV)laser with a wavelength of 355 nm and a repetition rate of 10 *** is a highly promising approach for open channel microfluidics and microarray analysis due to its simplicity,the chemical and environmental stability of the coating,and the low cost.

关键词： Superhydrophobic ultraviolet(UV)laser ablation wettability open channels

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Frozen Landweber Iteration for Nonlinear Ill-Posed Problems

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 329-336页

作者： j.Xu B.Han L.Li Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100080China Department of Mathematics Harbin Institute of TechnologyHarbin 150001China

In this paper we propose a modification of the Landweber iteration termed frozen Landweber iteration for nonlinear ill-posed problems. A convergence analysis for this iteration is presented. The numerical performance of this frozen Landweber iteration for a nonlinear Hammerstein integral equation is compared with that of the Landweber iteration. We obtain a shorter running time of the frozen Landweber iteration based on the same convergence accuracy.

关键词： Ill-posed problem regularization Landweber iteration

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Crop Epigenomics： Identifying, Unlocking, and Harnessing Cryptic Variation in Crop Genomes

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Molecular Plant 2015年第6期8卷 860-870页

作者： Lexiang ji Drexel A. Neumann Robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA Institute of Bioinformatics University of Georgia Athens GA 30602 USA These authors contributed equally to this article.

DNA methylation is a key chromatin modification in plant genomes that is meiotically and mitotically her- itable, and at times is associated with gene expression and morphological variation. Benefiting from the increased availability of high-quality reference genome assemblies and methods to profile single-base res- olution DNA methylation states, DNA methylomes for many crop species are available. These efforts are making it possible to begin answering crucial questions, including understanding the role of DNA methyl- ation in developmental processes, its role in crop species evolution, and whether DNA methylation is dynamically altered and heritable in response to changes in the environment. These genome-wide maps provide evidence for the existence of silent epialleles in plant genomes which, once identified, can be tar- geted for reactivation leading to phenotypic variation.

关键词： epigenomics DNA methylation whole-genome bisulfite sequencing (WGBS) crops comparativegenomics

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