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51.
李钒 《天津职业院校联合学报》2014,(12):94-97
研究了稀释剂乙二醇二缩水甘油醚降低环氧树脂粘度的效果;选择了两种导热填料MgO和Al2O3复配环氧胶粘剂;研究了固化物的导热性能,最终确定在环氧树脂E-51和固化剂TE-80中添加40wt%的稀释剂乙二醇二缩水甘油醚和80wt%MgO得到低粘度导热环氧胶粘剂。 相似文献
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Katja Brøgger 《Globalisation, Societies & Education》2014,12(4):520-541
The Bologna Process is one of the most extensive examples of policy borrowing processes. Based on qualitative data, this article argues in favour of studying part of this process as ‘global smallness’, centring on the organisational effects of the implementation of a globalised curriculum. Through Derrida's notion on hauntology, Fenwick and Edward's analysis of multiple reals, and Barad's understanding of entanglement and time, this article explores how the implementation processes evoke simultaneously existing worlds of practices propelled by the agency of the past troubling present higher education reform. Finally, this article addresses how ongoing reforms tend to increase the stretch between ‘what is performed on the outside’ and ‘what is practiced on the inside’. 相似文献
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本文采用有限元方法对金刚石/铜复合材料的传热性进行数值模拟,建立多颗粒二维随机分布复合材料测试模型,研究金刚石颗粒体积分数、颗粒半径、颗粒形貌、粒径比及界面因素对金刚石/铜复合材料传热性能的影响规律及机制。结果表明:金刚石/铜复合材料的热导率随着金刚石体积分数的增大而升高;热导率随着粒径的增大而呈现先升高后降低的规律;方形金刚石颗粒的复合材料热导率高于球形颗粒的复合材料;在金刚石体积分数一定时,适量配比细颗粒可提高材料热导率;对金刚石表面镀覆层新物质(W、Cr、Ti)来等效金刚石和铜二者物理结合时的界面热阻。 相似文献
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《Journal of Cultural Heritage》2014,15(6):692-697
In this paper, we present an application of the infrared thermography to the study of illuminations. In particular, we analyze a 15th century antiphonary from the Biblioteca Angelica of Rome to characterize the conservation state and the structure of the illuminations on the occasion of its planned restoration. We show the results achieved from the stratigraphic investigation of the gilded surface, the parchment substrate and the underdrawing. The obtained information have been, then, used to direct the necessary restoration steps and also to assess the effectiveness of the treatments by a comparative analysis of the thermograms recorded before and after the restoration. 相似文献
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《Journal of Cultural Heritage》2014,15(2):199-202
The significant number of buildings constructed in the world before the appearance of compulsory earthquake projecting norms, as well as the subsequent construction in the safe seismic zones, requires a constant re-evaluation of the strength of the structures. For example, the 2009 earthquake happened in L’Aquila city (Italy), killed about 300 people. Furthermore, many old buildings, seriously damaged, were considered as historical monuments and their importance is still critical both from a cultural standpoint and for the city itself. On the basis of the surveys carried out by the Las.e.r. Laboratory (university of L’Aquila) before and after 2009 earthquake, this paper introduces the infrared thermography (IRT) as a mean to characterize particular thermal imprints that appear on ancient facades, employing the passive thermography, discussing the infrared images collected during several years, and analyzing their relationship with all kinds of influence factors, in order to validate the effectiveness of the technique and its role in preventive diagnosis. 相似文献
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针对目前已安装的烟气在线监测系统的组成、安装、故障处理及运行维护等问题进行简略性阐述。烟气污染物在线监测系统是实时、连续监测污染物参数的系统,主要监测烟气中的颗粒物浓度(或浊度)、气态污染物浓度(SO2、NOx、)、辅助参数(烟气温度、流速、氧量、湿度、压力)等【1】。颗粒物浓度监测方法有激光透射法、激光反散射法及电荷感应法,气态污染物浓度监测方法主要有完全抽取法、稀释法、电化学法3种。在电力行业中,颗粒物监测主要采用激光反散射法,气态污染物浓度监测主要采用完全抽取法。 相似文献
59.
针对二极管激光器端面泵浦Nd:YVO4晶体工作特点,提出矩形各向异性激光晶体热模型.在晶体周边冷却,两通光面绝热情况下,通过求解泊松热传导方程,精确计算出矩形截面Nd:YVO4激光晶体的温度分布,进而求解Nd:YVO4激光晶体端面热膨胀量以及不同泵浦功率下的热焦距.研究结果表明,在泵浦功率为20 W时,激光晶体泵浦面最高升温503.4 K,最大热形变量5.42μm.对激光晶体温度场分布和端面热形变的研究,为解决晶体热效应提供了理论基础. 相似文献
60.
Tavis-Cummings模型中原子的纠缠度 总被引:1,自引:0,他引:1
1 Introduction Superposition principleis one of the fundamentals inquantum mechanics . A two-level atom may be in theground state |0〉,the excited state |1〉or the superpo-sition statesC0|0〉 C1|1〉. The coefficientsC0andC1are complex probability amplitudes of |0〉and |1〉respectively. For a system consisting of two atoms ,the state of total system may be in the direct productstates |0 ,1〉or |1 ,0〉. According to the superpositionprinciple ,the total system may also beinthe superpo-sition s… 相似文献