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Hydrological Responses and Flow Pathways in an Acrisol on a Forested Hillslope with a Monsoonal Subtropical Climate

Pedosphere 2017年第6期27卷 1037-1048页

作者： lars-erik SORBOTTEN Jannes STOLTE WANG Yanhui Jan MULDER Norconsult AS N-1338 Sandvika(Norway) Norwegian Institute of Bioeconomy Research(NIBIO) N-1430 Aas(Norway) Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091(China) Department of Environmental Sciences Norwegian University of Life SciencesN-1432 Aas(Norway)

The nature of subsurface flow depends largely on hydraulic conductivity of the vadoze zone, permeability of the underlying bedrock, existence of soil layers differing in hydraulic properties and macropore content, soil depth, and slope *** of flow pathways on forested hillslopes is essential to understand hydrological dynamics and solute transport ***, with their argic Bt horizons, are challenging in this *** further elucidate flow pathways of water and short-term variability of soil moisture patterns in Acrisols, a field study was conducted on a forested hillslope in a sub-catchment of the Tie Shan Ping(TSP)watershed, 25 km northeast of Chongqing City, *** catchment is covered by a mixed secondary forest dominated by Masson pine(Pinus massoniana).Soil saturated hydraulic conductivity(K sat) was significantly reduced at the interface between the AB and Bt horizons(2.6 × 10^(-5) vs.1.2 × 10^(-6) m s^(-1)), which led to that the flow volume generated in the Bt horizon was of little quantitative importance compared to that in the AB *** was a marked decrease in porosity between the OA and AB horizons, with a further decrease deeper in the mineral ***, the content of soil pores > 300 μm was higher in the AB horizon(14.3%)than in the Bt horizon(6.5%).This explained the difference in soil K sat *** study showed that Bt horizon had limited water transport capability, forcing part of the infiltrated rainwater as interflow through the OA and AB ***, the topsoil responded quickly to rainfall events, causing frequent cycles of saturation and aeration of soil pores.

关键词： dye tracer hillslope hydrology hydraulic conductivity preferential flow soil pores subsurface lateral flow

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Surface integral analogy approaches for predicting noise from 3D high-lift low-noise wings

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Acta Mechanica Sinica 2014年第3期30卷 326-338页

作者： Hua-Dong Yao lars Davidson lars-erik eriksson Shia-Hui Peng Olof Grundestam Peter E.Eliasson Department of Applied Mechanics Chalmers University of Technology Department of Aeronautics and Systems Technology Swedish Defence Research Agency (FOI)

Three surface integral approaches of the acoustic analogies are studied to predict the noise from three concep- tual configurations of three-dimensional high-lift low-noise wings. The approaches refer to the Kirchhoff method, the Ffowcs Williams and Hawkings （FW-H） method of the permeable integral surface and the Curle method that is known as a special case of the FW-H method. The first two approaches are used to compute the noise generated by the core flow region where the energetic structures exist. The last approach is adopted to predict the noise specially from the pressure perturbation on the wall. A new way to con- struct the integral surface that encloses the core region is proposed for the first two methods. Considering the local properties of the flow around the complex object-the actual wing with high-lift devices-the integral surface based on the vorticity is constructed to follow the flow structures. The surface location is discussed for the Kirchhoff method and the FW-H method because a common surface is used for them. The noise from the core flow region is studied on the basis of the dependent integral quantities, which are indicated by the Kirchhoff formulation and by the FW-H formulation. The role of each wall component on noise contribution is analyzed using the Curle formulation. Effects of the volume integral terms of Lighthill＇s stress tensors on the noise pre-diction are then evaluated by comparing the results of the Curle method with the other two methods.

关键词： Aero-acoustics High-lift facilities Surface integral approaches of acoustic analogy

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Compressively-strained GaSb nanowires with core-shell heterostructures

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Nano Research 2020年第9期13卷 2517-2524页

作者： Zhongyunshen Zhu Johannes Svensson Axel R.Persson Reine Wallenberg Andrei V.Gromov lars-erik Wernersson Departm ent of Electrical and Information Technology Lund UniversityBox 11822100 LundSweden Centre for Analysis and Synthesis Lund UniversityBox 12422100 Lundt Sweden NanoLund Lund UniversityBox 11822100 LundSweden EaStCHEM School of ChemistryUniversity of EdinburghEdinburgh EH93FJUK

GaSb-based nanowires in a gate-all-around geometry are good candidates for binary p-type transistors,however they require the introduction of compressive strain to enhance the transport ***,we for the first time demonstrate epitaxial GaSb-GaASxSb1-x core-shell nanowires with a compressively strained *** axial and hydrostatic strain in GaSb core have been measured by X-ray diffraction(XRD)and Raman scattering,*** optimal sample,almost without plastic relaxation,has an axial strain of-0.88%and a hydrostatic strain of-1.46%,leading to a noticeable effect where the light hole band is calculated to be 33.4 meV above the heavy hole band at the *** valence band feature offers more light holes to contribute the transport process,and thus may provide enhanced hole mobility by reducing both the interband scattering and the hole effective *** results show that lattice-mismatched epitaxial core-shell heterostructures of high quality can also be realized in the promising yet demanding GaSb-based system.

关键词： compressive strain GaSb-GaAsxSbi-x core-shell nanowires heterostructure p-type transistors

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The 2006 ICRP Recommendations of the International Commission on Radiological Protection

The 2006 ICRP Recommendations of the International Commissio...

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The Second Asian and Oceanic Congress for Radiation Protection

作者： lars-erik Holm Chairman of ICRP Swedish Radiation Protection Authority 171 16 STOCKHOLM Sweden

The current recommendations of the International Commission on Radiological Protection （ICRP） were published in 1991. Since then, ICRP has published additional recommendations, and the system of protection has become increasingly complex. New scientific data have made it necessary to update the biological and physical assumptions underlying the recommendations. The Commission has decided to revise its recommendations while at the same time maintaining stability with the previous recommendations. The international consultation on the draft recommendations has involved health physics professionals all around the world. A revised draft was be put on ICRP’s website for consultation during the summer of 2006. When ICRP adopts its revised recommendations, 16 years would have passed since the 1990 recommendations were adopted.

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Exceptionally preserved brachiopods from the Chengjiang Lagerst(a|¨)tte(Yunnan,China):Perspectives on the Cambrian explosion of metazoans

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Science Foundation in China 2013年第2期21卷 66-80页

作者： ZHANG ZhiFei HOLMER lars erik State Key Laboratory of Continental Dynamics Early Life InstituteNorthwest University LPS Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences Department of Earth Sciences PalaeobiologyUppsala UniversityVillavgen 16SE-752 36 UppsalaSweden

The Cambrian explosion was coined to describe the geologically sudden appearance of numerous bilaterian body plans(Phyla)around the Ediacaran-Cambrian transition,around 565-520million years *** explanations and conjectures have been postulated in order to explain the pattern and duration of this explosive radiation of many different phyla of early ***,we focus on the evolution of a phylum of marine suspension-feeding animals—the brachiopods,as exemplified by the exceptionally preserved taxa from the celebrated Chengjiang Konservat Lagerst(a|¨)tte(Yunnan,China).The abundant soft-bodied preservation at these fossil quarries gives us the only firm insights into what brachiopods looked like and how they functioned and lived when they first appeared on the *** of Chengjiang brachiopods demonstrate that the early animals developed a remarkably varied organization of tissues and organs shortly after the onset of Cambrian *** the marine suspension-feeding brachiopods,most importantly the tentaculate feeding structure of early brachiopods is already differentiated into two shapes of lophophore,anteriorly coiled(spiralled)and posteriorly arching tentacle crowns and the unique latter type was previously not documented from fossil and living *** unlike any known Recent brachiopod,all the known Cambrian brachiopods from Chengjiang have an open digestive tract that was disposed either as a Ushaped gut in linguliform and stem group brachiopods,or straight gut with a posterior anus in some calcareous-shelled ***,in contrast toliving lingulids,all the Cambrian brachiopods have an epibenthic lifestyle either cemented by a ventral valve or attached by variable pedicles to establish complex ecological community encompassing primary tierers and variable secondary *** is therefore assumed that brachiopods were the first benthic metazoan that achieved their success in ecological stratification and tiering complexity by lat

关键词： Cambrian explosion Chengjiang fauna Metazoans Brachiopods Soft-tissue preservation

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ICRP有关非人类物种保护的进展

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辐射防护 2004年第Z1期24卷 47-51页

作者： lars-erik Holm 瑞典辐射防护局斯德哥尔摩171 16瑞典

国际放射防护委员会(ICRP)正在对建议书进行修订.到目前为止,如何对非人类物种进行辐射效应的评价或管理,委员会还没有出版任何建议书.2000年,ICRP专门成立了一个任务组考虑这个问题,并于最近接受了工作组的报告.这份报告介绍了ICRP在... 详细信息

国际放射防护委员会(ICRP)正在对建议书进行修订.到目前为止,如何对非人类物种进行辐射效应的评价或管理,委员会还没有出版任何建议书.2000年,ICRP专门成立了一个任务组考虑这个问题,并于最近接受了工作组的报告.这份报告介绍了ICRP在这一重要的和正在开发的领域中所扮演的角色,这是基于已建立的用于人类保护的方法以及对于ICRP放射防护领域的特殊实践.ICRP将开发一个小型的参考动物和参考植物系列,加上与之相关的数据资料,对于一些已经确定类型的少量的动物和植物,可以用作更深入的理解和解释对照射与剂量、剂量与某种特定效应之间关系的基础.这一概念类似于人类放射防护中的参考个体(参考人)的应用,是剂量计算和确定的基础.委员会已经建立了一个新的任务组,继续这方面的工作,以确定感兴趣的效应终点和ICRP要使用的参考生物的类型,并确定一套用于评价和管理对非人类物种辐射照射的参考剂量模型.

关键词：非人类物种国际放射防护委员会参考剂量模型辐射效应建议书理解和解释计算和确定植物辐射照射数据资料评价开发基础管理动物报告工作组概念类参考人应用

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13%Cr不锈钢的激光复合焊工艺

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电焊机 2010年第11期40卷 82-84页

作者： lars-erik Stridn 伊萨焊接切割器材有限公司

激光-MIG复合电弧焊接工艺综合了激光焊接和电弧焊接的优点,具有低热输入(0.25 kJ/mm)、高焊接速度(55～60 mm/s)、低变形等特点。应用在巴士和卡车底盘的马氏体不锈钢的焊接中取得了很好的效果,通过实验证明,激光-MIG复合焊的焊缝成形... 详细信息

激光-MIG复合电弧焊接工艺综合了激光焊接和电弧焊接的优点,具有低热输入(0.25 kJ/mm)、高焊接速度(55～60 mm/s)、低变形等特点。应用在巴士和卡车底盘的马氏体不锈钢的焊接中取得了很好的效果,通过实验证明,激光-MIG复合焊的焊缝成形良好,接头力学性能、母材疲劳性能优越,其效率是普通MIG焊接的6.5倍。

关键词：超级奥氏体不锈钢激光复合焊

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主席致辞

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辐射防护 2004年第Z1期24卷 52-56页

作者： lars-erik Holm

　　部长夫人,部长阁下,尊敬的各位来宾,亲爱的同事们,热烈欢迎大家参加本次电离辐射效应环境保护国际大会.……

关键词：环境保护国际大会辐射效应部长来宾电离

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Low Porosity in Cast Magnesium Welds by Advanced Laser Twin-Spot Welding

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Materials Sciences and Applications 2019年第1期10卷 53-64页

作者： Karl Fahlstrom Jon Blackburn Leif Karlsson lars-erik Svensson Swerea KIMAB KistaSweden University West TrollhattanSweden TWI Ltd. CambridgeUK

Porosity is reported to be a major issue when welding cast magnesium. Therefore, it is important to understand the pore formation mechanisms and find procedures that could be used to reduce porosity. This study investigated the possibility of using twin-spot optics for reducing the porosity in laser welded cast magnesium. Two twin-spot welding setups were compared using either a beam splitter or twin-spot welding with primary and secondary (placed in front of the primary optic) optics. The results showed that welding with a dual optic setup with a defocused secondary beam reduced the volumetric porosity in the weld to 5%. The highest levels of volumetric porosity were 30%, and were a result of using the dual optic setup, but with a defocused primary beam. No clear relation between the level of porosity and power or welding speed was found. It was found that the amount of porosity depended on the balance of the energy input (controlled by defocusing) between the two beams. Porosity formation can be reduced if the energy from the first beam results in the nucleation and initial growth of pores. Reheating by the second beam then allows the pores to grow and escape from the molten material without melting additional base material. Furthermore, twin-spot welding is shown to be a promising combination of a production friendly solution and high quality welding.

关键词： Laser Welding Cast Magnesium Twin-Spot Metallurgy Porosity Automotive AM50 Alloy

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Adaptive-optical 3D microscopy for microfluidic multiphase flows

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Light(Advanced Manufacturing) 2024年第3期5卷 105-119页

作者： Clemens Bilsing erik Nützenadel Sebastian Burgmann Jürgen Czarske lars Büttner Laboratory of Measurement and Sensor System Techniques TUD Dresden University of Technology01069 DresdenGermany Chair of Fluid Mechanics Bergische Universitát Wuppertal42119 WuppertalGermany BIOLAS Laboratory of Measurement and Sensor System Techniques01069 DresdenGermany

Measurements based on optical microscopy can be severely impaired if the access exhibits variations of the refractive *** the case of fluctuating liquid-gas boundaries,refraction introduces dynamical aberrations that increase the measurement *** is prevalent at multiphase flows(***,film flows)that occur in many technical applications as for example in coating and cleaning processes and the water management in fuel *** this paper,we present a novel approach based on adaptive optics for correcting the dynamical aberrations in real time and thus reducing the measurement *** shape of the fluctuating water-air interface is sampled with a reflecting light beam(Fresnel Guide Star)and a Hartmann-Shack sensor which makes it possible to correct its influence with a deformable mirror in a closed ***-dimensional flow measurements are achieved by using a double-helix point spread *** measure the flow inside a sessile,oscillating 50-μl droplet on an opaque gas diffusion layer for fuel cells and show that the temporally varying refraction at the droplet surface causes a systematic underestimation of the flow field magnitude corresponding to the first droplet eigenmode which plays a major role in their detachment *** demonstrate that the adaptive optics correction is able to reduce this systematic ***,the adaptive optics system can pave the way to a deeper understanding of water droplet formation and detachment which can help to improve the efficiency of fuels cells.

关键词： Double-Helix point spread function Adaptive optics Particle tracking velocimetry Aberration correction Depth-resolving microscopy Closed-loop control

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