排序方式: 共有11条查询结果,搜索用时 16 毫秒
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利用金属有机物化学气相沉积方法,在n型6H-SiC衬底上制备了15对Si掺杂Al_(0.19)Ga_(0.81)N/Al_(0.37)Ga_(0.63)N DBR,并采用低温AlN缓冲层有效抑制了DBR结构中裂纹的产生,得到了表面均方根粗糙度仅为0.4 nm且导电性能良好的n型DBR,其在369 nm处峰值反射率为68%,阻带宽度为10 nm。在获得导电DBR的基础上,进一步在n型6H-SiC衬底上构建了有、无DBR的垂直结构紫外LED。对比两者电致发光光谱,发现DBR结构的引入有效增强了LED紫外发光强度。 相似文献
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Asymmetric simple exclusion processes with complex lattice geometries: A review of models and phenomena 下载免费PDF全文
We summarize the findings of a large number of studies concerning the totally asymmetric simple exclusion process (TASEP) with complex lattice geometries. The TASEP has been recognized as a paradigm in modeling and analyzing non-equilibrium traffic systems. The paper surveys both the observed physical phenomena and several popular meanfield approaches used to analyze the extended TASEP models. Several interesting physical phenomena, such as phase separation, spontaneous symmetry breaking, and the finite-size effect, have been identified and explained. The future investigations of the extended TASEP with complex lattice geometries are also introduced. This paper may help to obtain a better understanding of non-equilibrium systems. 相似文献
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本文叙述了用于稳态超导磁镜装置注入器的H_2~ 离子源的实验结果。由于改进了引出系统的电场形态,使引出区平均电场达106千伏/厘米,引出离子束为700毫安,束密度为400毫安/厘米。在引出最佳状态下,H_2~ 束含量为40%,束流强为130毫安,经过四极磁透镜聚焦,传输到距源11.8米处的流强为50毫安,经4×6厘米的限制孔注入到捕集室中为15毫安。 相似文献
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In this paper a cellular automaton model is proposed to describe driver behavior at a single-lane urban roundabout. Driver behavior has been considered as heterogeneous and inconsistent. Most traffic papers in the literature just discussed heterogeneous driver behavior, to our best knowledge. Two truncated Gaussian distributions are used to model heterogeneous and inconsistent driver behavior, respectively. The physical meanings of two truncated distributions are indicated. This method may help enhance a better understanding of driver behavior at roundabout traffic, and even possibly provide references for roundabout design and management. 相似文献
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本文扼要地介绍了三束同步混合注入装置,给出离子束源、原子束源和电子束源的设计和调试结果,还给出三束动态混合调试结果及初步开展的动态混合离子注入工艺开发与应用情况。三束同步处理和电子束的活化作用是该装置的主要特点。 相似文献
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一、引 言 在科学技术领域中,离子源的应用越来越广泛,形成了一门独立的学科——离子应用科学。尤其是70年代以来由于离子注入技术应用到材料表面改性的研究取得进展,从而使离子注入技术得到发展。 离子注入材料表面改性是一门新技术,它的优点是离子注入不通过加热形成特定的原子混合,又能快速引入晶格缺陷,从而改变金属的微观结构及相成分,最后导致金属宏观性质的改变。 相似文献
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本文给出了装置机械对中的方法和结果,叙述了氢分子离子束物理对中调试情况,着重讨论了影响粒子束物理对中的因素和提高粒子束传输效率的措施。 相似文献
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