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温压引起科学上的兴趣

粉末冶金工业 1997年第2期7卷 10-15页

作者： U.Engstrm b.johansson O.Jacobson 亓家钟 HgansAb KolsvaSinterteknikAb

为提高粉末冶金对其他制造技术的竞争性，需要适宜的合金系以及在降低加工费用的情况下提高力学性能并保持公差控制精度的工艺技术。在加热了的模具中压制加热的粉末是一种经一道工序就使密度提高到7.2～7.5g／cm3的新工艺。通过该工艺... 详细信息

为提高粉末冶金对其他制造技术的竞争性，需要适宜的合金系以及在降低加工费用的情况下提高力学性能并保持公差控制精度的工艺技术。在加热了的模具中压制加热的粉末是一种经一道工序就使密度提高到7.2～7.5g／cm3的新工艺。通过该工艺，可以得到相当于复压／复烧的密度水准与力学性能。然而，通过温压提高性能须兼而保持与传统粉冶工艺路线相同等级的公差猜度。本文介绍了这种特性粉末以及一些低合金粉冶材料（在温压与烧结后）的力学性能。同时也叙述了用温压工艺生产部件时有关公差精度的一些试验结果。

关键词：温压性能公差粉末冶金

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经过或未经过高压氧处理的种植体在放射线处理后的大鼠胫骨中骨整合现象的实验研究

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中国口腔医学继续教育杂志 2020年第3期23卷 150-156页

作者： Jan Nyberg Sven Hertzman borje Svensson CariNa b.johansson 曾维铭(译) 不详中山大学北校区广东省广州市

研究目的:高压氧(Hyperbaric oxygen,HbO)疗法被推荐用来增强放射线照射后骨中种植体的骨整合。本研究旨在进一步探讨高压氧对放射线照射后骨组织中种植体的骨整合的影响。材料与方法:本研究为16只大鼠的体内实验研究。对每一只大鼠的... 详细信息

研究目的:高压氧(Hyperbaric oxygen,HbO)疗法被推荐用来增强放射线照射后骨中种植体的骨整合。本研究旨在进一步探讨高压氧对放射线照射后骨组织中种植体的骨整合的影响。材料与方法:本研究为16只大鼠的体内实验研究。对每一只大鼠的一只后腿进行20G y的单组外部放射线照射.而另一只后腿作为非放射线照射的控制。照射三天后.在每个胫骨结节中都植入种植体。将大鼠分为两组:非高压氧处理组(组1)和高压氧处理组(组2)。在照射五周后,进行扭矩测试。将带有周围组织的种植体制备为未脱耗的硬组织切片和磨片,随后对骨-种植体接触区域(bone-to-implant contact,bIC)和骨区域(bone area,bA)进行组织形态学观察。再生的骨组织也用双能X线骨密度检测法进行测量。结果:非高压氧处理组大鼠(组1)与高压氧处理组的大鼠(组2)相比.在所有被调查的参数中.未接受放射线照射组被证明值更高.但没有统计学意义。但是.骨区域的平均值照射侧明显高于非照射对照侧。结论:在本研究中.高压氧治疗对在接受放射线照射的骨中种植体的骨整合无显著影响。

关键词：骨口腔种植高压氧治疗骨整合放疗

培养人胎脑细胞在大鼠脑梗塞灶内的分化和整合

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培养人胎脑细胞在大鼠脑梗塞灶内的分化和整合

A Meshless Regularization Method for a Two-Dimensional Two-Phase Linear Inverse Stefan Problem

“科技增强国力，青年开创未来——携手走向辉煌的新世纪”中国科协第三届青年学术年会

作者：曾进胜 bengt Mattsson barbro b.johansson Department of Experimental Neurology Wallenberg Neoroscience CenterLund University HospitalSweden

为探讨神经移植治疗脑梗塞的可能性,本研究将正常人胚胎大脑皮层神经元和星形胶质细胞混合培养后,移植到免疫抑制的自发性高血压大鼠的大脑皮层梗塞灶内,并与未移植的脑梗塞大鼠作对照。8w后取大鼠脑作免疫细胞化学检查。结果发现,移植... 详细信息

为探讨神经移植治疗脑梗塞的可能性,本研究将正常人胚胎大脑皮层神经元和星形胶质细胞混合培养后,移植到免疫抑制的自发性高血压大鼠的大脑皮层梗塞灶内,并与未移植的脑梗塞大鼠作对照。8w后取大鼠脑作免疫细胞化学检查。结果发现,移植了人胎脑细胞的8只存活大鼠中,5只有移植物生长。移植物内有新生血管,细胞有分层排列的趋势。免疫细胞化学染色证实移植物内有细胞分化,并存在大量星形胶质细胞和神经元。神经元的树突和轴突汇集成束,整合到宿主脑内。表明培养人胎脑细胞能在免疫抑制大鼠的脑梗塞灶内生长、分化和整合。神经移植治疗脑梗塞有临床应用的潜在可能性。

关键词：脑梗塞神经移植大鼠

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Advances in Applied Mathematics and Mechanics 2013年第6期5卷 825-845页

作者： b.Tomas johansson Daniel Lesnic Thomas Reeve Department of Science and Technology Campus Norrk¨opingLink¨oping UniversitySweden Department of AppliedMathematics University of LeedsLeeds LS29JTUK School of Mathematics University of BirminghamBirmingham B152TTUK

In this paper,a meshless regularization method of fundamental solutions is proposed for a two-dimensional,two-phase linear inverse Stefan *** numerical implementation and analysis are challenging since one needs to handle composite materials in higher ***,the inverse Stefan problem is ill-posed since small errors in the input data cause large errors in the desired output ***,regularization is necessary in order to obtain a stable *** results for several benchmark test examples are presented and discussed.

关键词： Heat conduction method of fundamental solutions(MFS) inverse Stefan problem two-phase change

Nuclear Phytochrome b Regulates Leaf Flattening through Phytochrome Interacting Factors

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Molecular Plant 2014年第11期7卷 1693-1696页

作者： Henrik johansson Jon Hughes Department of Plant Physiology Justus Liebig University D35390 Giessen Germany

Dear Editor, Plants are equipped with an array of photorecep- tors to measure UV-b, blue, red, and far-red light in order to monitor their light environment. However, although both synergistic and antagonistic interactions have been described between blue and red light signals （Casal, 2000）, little is known about how different light signals are inte- grated into modulate plant growth and development.

关键词： ARAbIDOPSIS PHOTOTROPIN AUXIN PIF4 LIGHT

Virtual Reality As a New Tool in the City Planning Process

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Tsinghua Science and Technology 2008年第S1期13卷 255-260页

作者： Kaj Sunesson Carl Martin Allwood Dan Paulin Ilona Heldal Mattias Roupé Mikael johansson brje Westerdahl Chalmers University of Technology

The introduction of virtual reality (VR)-models in the city planning process will cause changes in the traditional roles of the involved parties. In order to better understand some of these changes, the events involving the use of VR-models in an architectural competition concerning rebuilding-proposals for the city library in a Swedish city were analyzed. The study shows that VR was introduced into the competition as an extra add-on and that the VR-presentation was experienced as useful by the jury. The transformation of the architects’ contributions into VR was experienced as problematic by the architects, partly because they lost full control over the presentation. In the future architects are likely to have to produce the VR-models for their proposals themselves. This may make it more difficult for smaller architectural firms to enter the market but their proposals will be more accessible to a wider group of stakeholders.

关键词： architecture architectural competition city planning construction planning VR-models

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Industrial minerals and rocks, aggregates and natural stones in the Nordic countries

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Episodes 2008年第1期31卷 133-139页

作者： Kurt johansson Rune b. Larsen Markku J. Lehtinen Lars Persson Mika Raeisaenen Stig A. Schack Pedersen Paer Weihed Nils-Gunnar Wik Swedish Stone Industries Federation Industrigatan 6 SE-291 36 Kristianstad Sweden. NTNU NO-7491 Trondheim. Norway. Nordkalk Oyj Abp Poikkitie 1 FI-53500 Lappeenranta Finland. Geological Survey of Sweden SE-751 87 Uppsala Sweden. Geological Survey of Finland PO Box 96 FI-02151 Espoo Finland. Geological Survey of Denmark and Greenland Ф. Voldgade 10 DK-1350 Cph. Denmark. Division of Ore Geology and Applied Geophysics Lulea University of Technology SE-971 87 Lulea Sweden. Geological Survey of Sweden SE-223 50 Lund Sweden.

The Nordic countries, including Greenland, have a long tradition in mining. The industrial minerals sector is expanding in most Nordic countries and extensive development has taken place during the last few years. The main commodities mined are carbonate rocks, quartz, feldspar, apatite, olivine and talc. A number of diferent types of dimension stones are quarried in all countries. Rock aggregates are increasingly important, replacing sand and gravel aggregate as construction materials in some countries due to the need to protect ground water supplies.

关键词：工业矿产岩石集合体天然石材北欧地区

Volatile Organic Compound Emissions when Drying Wood Particles at High Dewpoints

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Chinese Journal of Chemical Engineering 2004年第6期12卷 767-772页

作者： Inge johansson Tobias Karlsson Roland Wimmerstedt S.E.P. Scandinavian Energy Project Ab bror Nilssons g. 16 SE-417 55 Goteborg SwedenThurne Teknik AB Heliosvagen 1 b SE-120 30 STOCKHOLM SwedenChemical Engineering Lund University P.O. Box 124 SE-221 00 LUND Sweden

Emission of volatile organic compounds (VOCs) during drying of wood particles for particleboard manufacture, or for production of refined biofuels, is a potential environmental problem. The aim of this work is to study the emissions of VOCs during drying, and the influence on the emissions by different drying *** experiments have mainly been done in a batch fluidized bed dryer, but measurements have also been done in a, pilot scale, continuous fluidized bed dryer. The parameters studied are air flow rate through the bed, air temperature, air dewpoint, and bed height. Since the present trend in biofuels and particle drying is towards very high dewpoints during drying, some measurements have been made at dewpoints up to 95℃, corresponding to a water content of 3.2 kg water per kilogram dry air. The emissions have been measured in two different ways,online during drying with a flame ionization detector and through wood analyses of the terpene content in the wood particles before and after drying. Substantial work has been made in developing the latter method as well as developing the drying equipment to be able to produce a wide range of conditions of the drying medium. It was shown that the VOCs emitted, during wood particle drying, mainly consist of terpenes. The behavior of the emissions was typical, at first contact with the drying gas a sharp peak in the release rate was detected. After that,the release rate stabilizes and declines slowly to a point where the material temperature increases and results in a second small peak in the release rate. Typically 80%-90% of the initial terpene content in the material was emitted during drying to low moisture content and it is not possible to significantly influence this release by changing the drying conditions. Up to 50% of the emitted terpenes are released during a very short period after contact with the drying medium. This fact could be utilized by employing a 2-step drying process. The fact that the VOC con

关键词： drying biofuels particleboard volatile organic compound high dewpoints

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Effects of Alternative Nitrogen Management Regimes on Production of Eucalyptus in Tropics and Sub-tropics

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Journal of Agricultural Science and Technology(b) 2014年第5期4卷 341-351页

作者： Moses Otuba johansson Karl-Erik Nabuin Zonal Agricultural Research and Development Institute Soroti 256 Uganda Department of Forest Products Faculty of Forest Sciences Swedish University of Agricultural Sciences Uppsala SE75007Sweden

This paper presents the effects of alternative nitrogen management regimes on production of Eucalyptus in tropics and sub-tropics carried out in autumn, 2011. The aim of the study was to review alternative nitrogen management regimes that could enhance the positive effects and reduce negative effects of different Eucalyptus species in the perspective of smallholders. Literature review was used to survey the alternative nitrogen management regimes on eucalyptus trees. There was a significant improvement （P ≤ 0.01） in mean annual increment （MAI） as measured at seven years of Eucalyptus tereticornis in the plots planted with only legume, pueraria and stylosanthes, compared to that of the control on altitude 150 m and rainfall of 2,000 mm at the age of seven years, The MAI of Eucalyptus urophylla and Eucalyptus camaldulensis in plots planted with beans and rice shows a significant improvement （P ≤ 0.05） over the control treatment. Only the plots treated with nitrogen fertilizer 550 kg/ha showed significant improvement （P ≤ 0.05） in terms of MAI of Eucalyptus nitens, compared to the control treatment. In general, it can be concluded that as these alternative management regimes enhance productivity of Eucalyptus woodlots, the challenge for the small-scale farmers is on how to manage them sustainably. Therefore, forest policies that take consideration of increasing production of Eucalyptus and managing biodiversity with reference to these alternative management regimes should be developed in tropics and sub-tropics.

关键词： Eucalyptus legumes management nitrogen sub-tropics tropics.