新型光学长程吸收池的仿真设计研究

为了解决传统的长程光学吸收池设计中镜面利用率低导致反射次数少的问题,根据传输矩阵理论,开展了离散型Herriott池的结构参数设计研究。基于MATLAB数值计算模拟详细研究了吸收池内光线的传输次数与机械结构参数、光线的入射位置及入射角之间的依赖关系。仿真结果为实际应用中设计便携式长程光学吸收池提供良好的参数和模型借鉴作用。     

随机抽样一致性算法在激光光谱中的应用研究

为了解决波长调制激光光谱技术探测大气痕量气体浓度中信号处理算法的不足,提出了一种基于随机抽样一致性算法的气体浓度反演算法。以大气甲醛分子的仿真信号和实际测量信号为例,进行了理论分析和实验研究,并与传统的最小二乘法相比较。结果表明,该算法具有较强的抗噪声和异常点干扰能力,尤其是在低信噪比的条件下,精确度可提高1个量级,体现出较高的可靠性和优越性。     

MTAODV:一种新的高速公路场景下VANET路由协议

在高速公路场景中,针对车辆间通信特性,在AODV的基础上提出了一种基于应用消息类型的改进路由协议(MTAODV).其核心思想是在路由建立过程中充分考虑VANET中应用消息的类型,从而减小路由请求洪泛范围,降低网络开销.仿真实验结果表明,与AODV协议相比,MTAODV协议能够有效地提高分组递交率,降低了路由开销,改善了分组时延和抖动.     

Nanofabrication of 50 nm zone plates through e-beam lithography with local proximity effect correction for x-ray imaging

High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmost zone-width is shrinking down to 50 nm or even below,patterning the zone plates with high aspect ratio by electron beam lithography still remains a challenge because of the proximity effect.The uneven charge distribution in the exposed resist is still frequently observed even after standard proximity effect correction(PEC),because of the large variety in the line width.This work develops a new strategy,nicknamed as local proximity effect correction(LPEC),efficiently modifying the deposited energy over the whole zone plate on the top of proximity effect correction.By this way,50 nm zone plates with the aspect ratio from 4:1 up to 15:1 and the duty cycle close to 0.5 have been fabricated.Their imaging capability in soft(1.3 keV)and hard(9 keV)x-ray,respectively,has been demonstrated in Shanghai Synchrotron Radiation Facility(SSRF)with the resolution of 50 nm.The local proximity effect correction developed in this work should also be generally significant for the generation of zone plates with high resolutions beyond 50 nm.