4O6.7～415.4nm和632.8nm辐射在人肺组织中的穿透深度

在对作者原有工作改进的基础上，应用自行研制的“光纤探针深度计”首次精确测定了Kr+紫激光406．7～415．4um和He-Ne激光632．8nm波长处新鲜离休人肺组织中光能流率分布，获得这两种重要波长处人肺正常组织和人肺腺鳞癌组织中光能流率的分布规律及光穿透深度的数值：（1）δnormal=0.08mm,δtumour=0.32mm(λ=406.7～415.4nm);(2)δnormal=1.19mm,δturmour=1.70mm(λ=632.8nm),并对现有人肺组织的光穿透深度数据作了总结和讨论．     

Dirac类氢原子的超对称方法研究

应用超对称方法研究了Ｄｉｒａｃ类氢原子问题，不需繁琐的数学处理，得到和严格解法完全一致的能量本征值谱及相应的本征函数。     

Visualized measurement of the acoustic levitation field based on digital holography with phase multiplication

By using digital holographic interferometory with phase multiplication, the visualized measurement of the acoustic levitation field (ALF) with single axis is carried out. The digital holograms of the ALF under different conditions are recorded by use of CCD. The corresponding digital holographic interferograms reflecting the sound pressure distribution and the interference phase distribution are obtained by numerical reconstruction and phase subtraction, which are consistent with the theoretical results. It indicates that the proposed digital holographic interferometory with phase multiplication can successfully double the fringe number of the interference phase patterns of the ALF and improve the measurement precision. Compared with the conventional optical holographic interferometory, digital holographic interferometory has the merits of quasi real-time, more exactitude and convenient operation, and it provides an effective way for studying the sound pressure distribution of the ALF.     

Fabrication and scanning tunneling microscopy studies of the Si(1 1 1)-(√31 × √31)-In surface

We report on the fabrication of single phase of the Si(1 1 1)-(√31 × √31)-In reconstruction surface, observed by scanning tunneling microscopy (STM) at room temperature. By depositing specific amounts of indium atoms while heating the Si(1 1 1)-(7 × 7) substrate at a critical temperature, the single phase of Si(1 1 1)-(√31 × √31)-In surfaces could be routinely obtained over the whole surface with large domains. This procedure is certified by our high-resolution STM images in the range of 5-700 nm. Besides, the high resolution STM images of the Si(1 1 1)-(√31 × √31)-In surface were also presented.     

Mass-analyzed Threshold Ionization Spectroscopy of Rotamers of p-ethoxyphenol Cations and Configuration Effect

利用双色双光子质量分辨的阈值电离光谱技术,研究了对位乙氧基苯酚顺式和反式两种构型的离子态振动特性. 测得顺式和反式精确的绝热电离势分别为61565±5和61670±5 cm^-1. 与对位甲氧基苯酚实验结果比较,顺式和反式的测得的绝热电离势分别降低了645和643 cm^-1. 从所得到的两种构型的高分辨离子态光谱中,可知顺式和反式不同构型对苯环平面的振动影响很小,而低频率的C-OC₂H₅弯曲振动在两种构型中都很活跃.     

Studies on the superconductivity for the “111” type iron arsenide superconductor

The “111” type Li _x FeAs (x ranges from 0.8 to 1.2) with Cu₂Sb type tetragonal structure was synthesized with T _c 18 K. The isostructure NaFeAs was further studied, which shows superconductivity with T _c up to 26 K. The effect of pressure on superconductivity was investigated.     

Non-collinear optical parametric chirped-pulse amplifier for few-cycle pulses

Modified parametric coupled equations for three-wave interaction in non-collinear optical parametric chirped-pulse amplification (OPCPA) are presented, in which the effects from the non-collinear configuration have been taken into account. By utilizing this new model, a two-stage OPCPA system based on a BBO crystal is numerically calculated with a split-step Fourier transform algorithm. Tracing the dynamics of the signal wave in the crystal reveals that in the first stage spectral gain narrowing occurs due to the weak input signal intensity and the non-uniform temporal distribution of the pump light. However, in the saturation regime the spectrum of the signal will be broadened as a consequence of back conversion. The simulation shows that it is crucial to correctly control the experimental parameters to balance both processes. For maximizing the energy-bandwidth product (EBP), an optimized configuration is sought by examining several parameters such as pump intensity, seed energy and crystal length. With a pump intensity of 7.75 GW/cm² and a crystal length between 3.75 and 4.25 mm pulses with a sub-10 fs duration can be amplified with a total gain of up to 1.7×10⁶.     

基于视觉的车辆与轨道相对振动状态测量方法研究

车辆与轨道相对振动状态对轨道线形测量有重要影响;分析了传统检测车辆与轨道相对振动状态测量方法的缺陷,提出一种基于视觉的车轨相对振动状态测量方法,以轨道建立世界坐标系,以车体建立车体坐标系。考虑相机镜头畸变,建立相机非线性模型,基于机器人手眼方法标定相机与车体,求解相机内外参数。依据车体运动姿态特征,推导基于双目机器视觉的车辆运动姿态偏移补偿计算方法;运用实验平台设计验证实验,通过计算所得的车体振动位移与真实值高度吻合,随着车速增加振动位移误差也随之增大,验证了该方法的正确性和可行性;提供一种车辆与轨道相对振动状态测量方法。     

基于SLAM的连续运动测量坐标转换算法研究

本文基于同步定位与地图创建(Simultaneous Localization and Mapping,SLAM)原理,通过双目视觉系统的坐标转换方法,建立动态坐标系与静态基准点之间的关系,实现连续运动测量。通过实验,设计运动路线,验证坐标转换算法,并得到了建立在世界坐标系下的空间线形曲线。实验结果表明：转换后的坐标,x、y、z三个方向的最大误差不超过0.734mm。     

基于CompactRIO的四旋翼飞控实时仿真平台设计

针对四旋翼无人机实时飞行控制系统的控制算法设计与参数整定,设计了一种基于CompactRIO的飞行控制系统实时仿真平台,该平台使用两台CompactRIO作为主控制器,分别在其嵌入式实时系统(VxWorks)中运行Simulink设计的无人机动力学模型与飞行控制系统模型,并使用LabVIEW开发PC上位机监控程序,用于调整飞行状态和整定控制参数。经试验证明,该平台实用性强,可视化程度高,实时性好,能较好地对四旋翼飞控系统进行实时仿真验证。