串联合成新型色烯-茚二酮类化合物

报道了一种合成新型色烯-茚二酮类化合物3的方法.该反应以简单易得的2-羟基查尔酮(1)和1,3-茚二酮(2)为原料,以甲苯为溶剂在无催化剂条件下进行反应.所有化合物的结构都通过了1H NMR,13C NMR,IR和HRMS的表征.该反应的可能机理为分子间迈克尔加成/分子内环化/氧化的串联过程.目标产物3a~3h的紫外最大吸收波长在464~482 nm之间.     

Measuring vibration by using fiber Bragg grating and demodulating it by blazed grating

A method of measuring vibration by using fiber Bragg grating (FBG) and demodulating the spectrum by blazed grating is introduced. The sensor system is made of a simple supported beam with a FBG adhered to its upper surface. A blazed grating is used to demodulate the changing spectrum that is got from the sensor system, and a line charge-coupled device (CCD) is used to accept the diffraction spectrum.Through analyzing the number of the CCD's pixels, we can get the amplitude of vibration and the change of the temperature. The experimental results show that the vibration amplitude of the exciter matches the detected signal under the stable frequency. The temperature shift and vibration signal are also successfully separated.     

反射相移对MEMS滤波器半峰全宽影响分析

以典型的基于MEMS的FP腔结构为例，用传输矩阵方法推导了考虑反射相移的半峰全宽的解析表达式.利用此解析表达式分别模拟了考虑反射相移的半峰全宽与干涉级次和FP腔两反射镜间距的关系，并将其与不考虑反射相移的半峰全宽进行了对比；同时将反射相移和反射率对半峰全宽的影响进行了比较分析.     

关于夫兰克——赫兹实验的讨论

引言著名的F—H实验被大多数原子物理学教材选用,作为阐明原子能级存在的实验事实。而且均仿照Franck和Hertz当年在论文中的表述方法,以激发电位曲线峰位的间距作为汞原子的第一激发电位。当前国内多数院校的近代物理实验中也均是这样处理的。然而实验中各种物理因素的影响较大,比较精确地确定峰位是困难     

新型1×4塑料光纤功率耦合器的研制

提出了一种新型的塑料光纤功率耦合器 ,该耦合器与传统的拉锥型和混合棒塑料光纤耦合器不同。理论分析了它的损耗特性。该耦合器基于塑料光纤本身的热特性 ,分别将塑料光纤进行拉锥和热缩构成耦合器的两端 ,结构简单 ,制作容易 ,实验结果表明其性能也可满足塑料光纤短距离通信网的要求     

Measuring vibration by using fiber Bragg grating and demodulating it by blazed grating

A method of measuring vibration by using fiber Bragg grating (FBG) and demodulating the spectrum by blazed grating is introduced. The sensor system is made of a simple supported beam with a FBG adhered to its upper surface. A blazed grating is used to demodulate the changing spectrum that is got from the sensor system, and a line charge-coupled device (CCD) is used to accept the diffraction spectrum. Through analyzing the number of the CCD's pixels, we can get the amplitude of vibration and the change of the temperature. The experimental results show that the vibration amplitude of the exciter matches the detected signal under the stable frequency. The temperature shift and vibration signal are also successfully separated.     

新型二元相MoS2/C纳米管的合成和机理研究

在900 ℃氢气气氛下, 通过热分解载有硫代钼酸铵的碳纳米管前驱物得到MoS₂/C二元相纳米管. 通过粉末X射线衍射(XRD)、高分辨透射电镜(HRTEM)、扫描电镜(SEM)和X射线能量散射仪(EDS)等方法对其形貌、结构和成分进行了表征. 结果表明, 我们合成了一种由两种材料组成管壁的新型纳米管, 并对其形成机理进行了研究.     

Reason for the loss of hydrophilicity of TiO_2 film and its photocatalytic regeneration

TiO2 film was prepared on soda-lime glass by sol-gel method. The water contact angle (θ) of the fresh TiO2 film is 0°. During storage in air, the surface of TiO2 film is gradually converted to the hydrophobic state. XPS and ITD results reveal that it is due to the adsorption of organic contaminants on TiO2 surface in air ambience. The lost hydrophilicity of TiO2 film can be regenerated by UV illumination.     

玻尔理论与量子力学矛盾析

众所周知，玻尔理论与量子力学在处理氢原子结构时存在着某些不同的结论．本文从波粒二象性和不确定关系出发，解释了存在不同结论的原因，从而进一步阐明了两者之间的联系和本质的区别．