部分空间和部分时间相干衍射高斯-谢尔模型脉冲光束在大气湍流中的光谱移动和光谱开关

基于非稳光场的相干光理论,研究了部分空间和部分时间相干高斯-谢尔模型脉冲光束在大气湍流中的光谱变化规律.给出了两者在大气湍流中的光谱传输公式.数值计算结果表明,由于光阑衍射效应的影响,光谱沿轴向、径向均出现蓝移或红移,随着相对传输距离z/z0、空间相干参数β和折射率结构常数C2n的增大,脉冲时间相干长度Tc的减小,轴向...     

High quality interpoly dielectrics deposited on thenitrided-polysilicon for nonvolatile memory devices

High quality interpoly dielectrics have been fabricated by using NH₃ and N₂O nitridation on polysilicon and deposition of tetra-ethyl-ortho-silicate (TEOS) oxide with N₂O annealing. The surface roughness of polysilicon is improved and the value of weak bonds is reduced due to nitrogen incorporation at the interface, which improves the integrity of interpoly dielectrics. The improvements include a higher barrier height, breakdown strength, and charge-to-breakdown, and a lower leakage current and charge trapping rate than counterparts. It is found that this method can simultaneously improve both charge-to-breakdown (up to 20 C/cm² ) and electric breakdown field (up to 17 MV/cm)     

An Instance-Learning-Based Intrusion-Detection System for Wireless Sensor Networks

This paper proposes an instance?learning?based intrusion?detection system (IL?IDS) for wireless sensor networks (WSNs). The goal of the proposed system is to detect routing attacks on a WSN. Taking an ...     

东鞍山烧结厂浮选中矿处理方法的试验研究

通过对东鞍山烧结厂浮选中矿性质的分析,提出了中矿单独处理方案,并对中矿单独处理的方法进行了试验研究,取得了理想的结果。     

2kW横流连续CO_2激光器的工作气体以Ar代He的研究

对管板式低气压放电结构、横流连续２ｋＷＣＯ２激光器以Ａｒ气取代部分Ｈｅ气进行了研究。Ｈｅ气的取代量（掺Ａｒ量）从２０％增加到６０％，工作气压在２．９３～４．２６ｋＰａ，放电电流在３～１１Ａ的范围，激光器放电稳定，运转正常，可获得良好的输出特性，如输出功率为１．７ｋＷ，电光转换效率为１６％。     

远红外自由电子激光器中超短光脉冲的产生

探讨了射频型远红外波导自由电子激光器（ＦＩＲ—ＦＥＬ）中产生超短光脉冲的可能性。由于短电子束辐射出与其长度相当的光脉冲．因此提出了选择适当的电子束起始相速度来确保正增益和光脉冲折射率沿相对滑移方向单调增加，这样当光脉冲渡越折射率渐变的“增益介质”—电子束团时．光脉冲前后沿将向中心相向移动而使其径向宽度被压缩。则可能获得远红外波段的高功率超短光脉冲。     

基于球形微粒的光学共振实现室温下的持久光谱烧孔

基于微腔光学共振机制，实现了尼罗蓝（ＮｉｌｅＢｌｕｅ）分子掺杂的微米尺寸球形聚合物微粒体系的室温持久光谱烧孔．该研究对于探索室温频域光存贮新机制新材料具有意义。     

全球信息网WWW

随着Ｉｎｔｅｒｎｅｔ的迅速发展，基于Ｉｎｔｅｒｎｅｔ的全球信息网－Ｗｏｒｌｄ－Ｗｉｄｅ Ｗｅｂ也得以飞速发展，本文叙述了全球信息网ＷＷＷ的基本构成原理、Ｗｅｂ浏览器工作原理及创建方法，并引出超媒体、超链点、超文本等新的概念。     

激光辐照40~#Cr钢的腐蚀电化学特性与腐蚀疲劳性能的研究

用对比的方法研究了不同激光辐照工艺对40~#Cr钢耐蚀性和腐蚀疲劳性能的影响。结果表明,激光相变硬化处理的耐蚀性优于激光表面重熔处理的试样的耐蚀性。经激光表面辐照处理后,其腐蚀疲劳寿命也显著提高。结合光镜和SEM分析了材料的耐蚀机理和腐蚀疲劳断裂的特征与机制。     

Energetic nitrocellulose coating: effective way to decrease sensitivity and modify surface property of HMX particles

Modifying the surface properties of energetic materials has theoretical and practical significance in the field of their application. In this paper, irregular cyclotetramethylene tetranitramine (HMX) particles were successfully coated by energetic nitrocellulose (NC), leading to the uniform NC-coated HMX particles. As coating materials, energetic (NC was chosen to decrease the sensitivity and modify the surface property of HMX particles, in order to expand their application furthermore. Scanning electron microscopy, laser particle size analysis, energy dispersive spectrometer, and Fourier-transform infrared (FT-IR) spectra were utilized to investigate the morphology, size, and coating quality of NC-coated HMX particles. These results indicated the effective preparation of composites structure. Moreover, the thermal behaviors of NC-coated HMX particles were investigated by simultaneous thermogravimetric and differential scanning calorimetry analysis, coupled with FT-IR and mass spectroscopy. These results showed that NC did not induce chemical properties change of HMX, only physical hydrogen bond was formed in the coating process. Finally, the friction sensitivity, impact sensitivity, and surface properties NC-coated HMX were investigated, and the results suggested that NC-coated HMX particles had better safety and depicted stronger interaction with the binder matrix than original HMX, owing to the stability of NC on the outer layer.