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61.
Ludovic Rapp Christophe Cibert Anne Patricia Alloncle Philippe Delaporte 《Applied Surface Science》2009,255(10):5439-5443
The laser-induced forward transfer technique has been performed on thin layers of conducting organic materials for applications in plastic micro-electronics.This process is a promising alternative for fabrication of organic electronic components on flexible supports when usual techniques, such like ink-jet printing, cannot be considered. For example, when the organic material has no solubility properties or when complex architectures are needed.Experiments on the influence of pulse duration (nanosecond and picosecond) and wavelength on a large range of fluences have been proceeded using different lasers. An optimization of the process has been carried out by inserting a thin layer of absorbing metallic material between the substrate and the organic film. The advantage of this technique is to preserve organic layers from being damaged by thermal and photochemical effects during the interaction.The morphology and thickness of the deposit have been investigated by optical and scanning electronic microscopy. This experimental study is supplemented by electrical characterization of the deposits. 相似文献
62.
本文报道三硼酸锂(LBO)晶体的瞬态前向相干多光子散射,实验表明LBO晶体内部同时发生x~(2)和x~(3)非线性相互作用过程,而未发现光耦合效应,测量了LBO晶体的光栅寿命上限. 相似文献
63.
电子束参量对轫致辐射照射量角分布的影响 总被引:2,自引:1,他引:1
本文研究了电子束半径,发射度及能量等参量对闪光X射线照射量在1m处角分布的影响。求得了使中心照射量最大,束半径与发射度之间应满足的拟合关系,表明了电子束能量越高,发射度越小,那么中心照射量就越大,照射量的空间分布就越理想。对电子细束入射位置和入射方向使用了解析法和随机抽样法求出,两种方法的数值计算所得的照射量分布符合得比较好。 相似文献
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65.
The process of planar detonation ignition, induced by a constant-velocitypiston or equivalently by a shock reflected from a stationarywall, is investigated using high-resolution one-dimensionalnumerical simulations. The standard one-step model with Arrheniuskinetics, which models thermally sensitive explosives, is employed.Emphasis is on comparing and contrasting the results of thefinite activation temperature simulations with high activationtemperature asymptotic predictions and previous simulations.During the induction phase, it is shown that the asymptoticresults give qualitatively good predictions. However, for parametersrepresentative of gaseous explosives, subsequent to thermalrunaway at the piston and the formation of a reaction wave,the high activation temperature asymptotic theory is qualitativelyincorrect for moderately high activation temperatures. It isshown that the results are very sensitive to the value of theactivation temperature, especially the distance from the pistonat which a secondary shock forms and the degree of unsteadinessin the reaction wave which moves away from the piston. The dependenceof the ignition evolution on the other parameters (initial shockMach number, heat of reaction and polytropic index) is alsoinvestigated. It is shown that qualitative predictions regardingthe dependence of the ignition evolution on each of the parameterscan be elucidated from finite activation temperature homogeneousexplosion calculations together with the high activation temperatureasymptotic shock ignition results. It is found that for sufficientlystrong initiating shocks the ignition evolution is qualitativelydifferent from cases studied previously in that no secondaryshock forms. For a high polytropic index, corresponding to asimple equation of state model for condensed phase explosives,the results are in much better qualitative agreement with theasymptotic theory. 相似文献
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67.
Kamal Shanazari Siamak Banei 《Numerical Methods for Partial Differential Equations》2023,39(2):1635-1651
We apply a boundary element dual reciprocity method (DRBEM) to the numerical solution of the forward–backward heat equation in a two-dimensional case. The method is employed for the spatial variable via the fundamental solution of the Laplace equation and the Crank–Nicolson finite difference scheme is utilized to treat the time variable. The physical domain is divided into two non-overlapping subdomains resulting in two standard forward and backward parabolic equations. The subproblems are then treated by the underlying method assuming a virtual boundary in the interface and starting with an initial approximate solution on this boundary followed by updating the solution by an iterative procedure. In addition, we show that the time discrete scheme is unconditionally stable and convergent using the energy method. Furthermore, some computational aspects will be suggested to efficiently deal with the formulation of the proposed method. Finally, two forward–backward problems, for which the exact solution is available, will be numerically solved for two different domains to demonstrate the efficiency of the proposed approach. 相似文献
68.
利用RCM(随机选取法)解反应流爆轰问题时,掌握影响流动参数随机涨落的主要因素是选择适当计算参数、保证得到正确结果的关键。各种流动参数的随机涨落相互关联,只需要搞清楚炸药未反应质量分数的随机涨落并做出分析,其它流动参数涨落的情况也就清楚了。给出了影响未反应质量分数涨落的因数,同时还给出了具体算例,检验所得结论的正确性。 相似文献
69.
建立了描述可燃粉全-氧气混合物爆轰波的一维两相反应流模型,用MacCormack有限差分格式求解了控制方程,成功地模拟了玉米粉-氧气混合物在氢-氧爆轰驱动下爆轰波的传播过程,其数值结果在接近稳态爆轰区时与实验规律有良好的一致性。 相似文献
70.