排序方式: 共有75条查询结果,搜索用时 15 毫秒
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首次在固相条件下微波辐射N,N-二烷基-4-亚硝基苯胺盐酸盐和2-萘酚生物快速合成苯并「a」吩恶嗪衍生物,得到苯并「a」吩恶嗪锌离子氯化物3a-3f,且收率较高。此外,N,N-二甲基-4-亚硝基苯胺盐酸盐和1,3-二羟基-2-萘甲酸乙酯的混合物在微波辐射下合成了一个新的激光染料9-二甲氨基-6-乙氧羰基-5H-苯并「a」的吩恶嗪-5-酮4。 相似文献
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The adiabatic theorem is a useful tool in processing quantum systems slowly evolving, but its practical application depends on the quantitative condition expressed by Hamiltonian's eigenvalues and eigenstates, which is usually taken as a sufficient condition. Recently, the sufficiency of the condition was questioned, and several counterexamples have been reported. Here we present a new solved model to show the insufficiency of the traditional quantitative adiabatic condition. 相似文献
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对于涂(自然)-邓(映蒲)提出的一个二元组合猜想,已验证了k≤39时的情形,本文在此基础上利用递推归纳的方法,给出了对任意的k,t≤219情形下涂-邓猜想的正确性证明. 相似文献
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Micromagnetic simulation on the dynamic susceptibility spectra of cobalt nanowires arrays: the effect of magnetostatic interaction 下载免费PDF全文
<正>Micromagnetic simulations have been performed to obtain the dynamic susceptibility spectra of 4×4 cobalt nanowire arrays with different spatial configurations and geometries.The susceptibility spectra of isolated wires have also been simulated for comparison purposes.It is found that the susceptibility spectrum of nanowire array bears a lot of similarities to that of an isolated wire,such as the occurrences of the edge mode and the bulk resonance mode. The simulation results also reveal that the susceptibility spectrum of nanowire array behaves like that of single isolated wire as the interwire distance grows to an extent,which is believed due to the decrease of magnetostatic interaction among nanowires,and can be further confirmed by the static magnetic hysteresis simulations.In comparison with single nanowire,magnetostatic interaction may increase or decrease the resonance frequencies of nanowire arrays assuming a certain interwire distance when the length of array increases.Our simulation results are also analysed by employing the Kittel equation and recent theoretical studies. 相似文献
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矢量传声器的核心组成器件是质点振速传感器,该传感器具有与频率无关的‘8'字指向性。本文在分析空气声质点振速传感器工作原理基础上,采用数值分析方法系统研究了质点振速传感器中敏感头桥式结构尺寸、热扩散和材料比热容等参数对频率响应的影响,着重分析了质点振速传感器最优灵敏度和低通滤波器效应。根据优化设计结果,采用MEMS工艺技术加工出敏感头桥式结构,并测试了0℃条件下Pt的电阻值R和热阻温度系数θ,以及传感器的频响曲线和‘8'指向性。实验结果表明:空气声质点振速传感器具有良好的声学性能。 相似文献
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由于在电致变色、显示、军事等领域的广泛应用,电致变色材料受到了人们越来越多的关注。本文综述了聚苯胺(PANI)类、聚噻吩(PTh)类、聚吡咯(PPy)类及复合导电聚合物电致变色材料的性能及其研究进展,同时简单地叙述了这些材料作为电致变色材料的应用前景,指出具有丰富颜色变化、良好的稳定性及成膜性的共聚物及有机/无机复合导电聚合物材料是未来电致变色材料发展的方向。 相似文献
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