ZnSe/SiO2复合薄膜光学常数与荧光光谱的研究

采用溶胶-凝胶工艺与原位生长技术，制备了ZnSe/SiO₂复合薄膜.X射线衍射分 析表明薄膜中ZnSe晶体呈立方闪锌矿结构.X射线荧光分析结果显示薄膜中Zn与Se摩尔比为1 ∶1.01—1∶1.19.利用场发射扫描电子显微镜观察了复合薄膜的表面形貌，结果表明复合薄 膜表面既存在尺寸约为400nm的ZnSe晶粒，也存在尺寸小于100nm的ZnSe晶粒.利用椭偏仪测 量了薄膜椭偏角Ψ，Δ与波长λ的关系，采用Maxwell-Garnett有效介质理论对薄膜的光学 常数、厚度、气孔率、ZnS 关键词： 2复合薄膜')" href="#">ZnSe/SiO₂复合薄膜 光学性质 椭偏光度法 荧光光谱     

国产六面顶压机多晶种法合成宝石级金刚石单晶

对国产六面顶压机平台下使用多晶种法合成宝石级金刚石单晶进行了系统的研究. 通过合理调整温度梯度法的合成腔体组装, 采用多晶种法, 探索多晶种法金刚石合成的压力和温度区间, 在单个合成腔体内放置3–5颗金刚石晶种, 成功合成出多颗(3–5)优质Ib型宝石级金刚石单晶. 多颗晶种的引入, 单次实验合成的多个金刚石晶体晶形及品质一致; 同时, 晶体的整体生长速度也有明显的增大. 多晶种法金刚石单晶合成的研究, 可以有效地利用腔体空间、提高单次金刚石单晶合成的效率, 解决压机大型化下高温高压资源利用率低的问题; 同时, 为宝石级金刚石单晶商业化生产提供重要的依据. 关键词： 金刚石 国产六面顶 多晶种 温度梯度法     

亚微秒脉冲表面介质阻挡放电等离子体诱导连续漩涡的研究

使用粒子激光图像测速技术对亚微秒脉冲激励表面介质阻挡放电激励器连续产生诱导漩涡进行了实验研究, 给出了包含脉冲重复频率和漩涡频率的双频率激励模式的具体形式. 实验过程中出现了原发型与继发型两类示踪粒子空白区, 前者由放电释热的微爆炸作用造成, 使得诱导流动远离壁面, 能够减小壁面摩擦阻力的作用; 以暴露电极左侧继发型空白区被完全吹除作为重复启动激励的临界点. 为提高控制效果应采用尽可能高的脉冲重复频率, 漩涡时间内脉冲数量应大于10, 最大诱导速度随脉冲数量增大而增大, 但动量传递效率降低. 使用亚微秒脉冲激励具备释热、体积力两种作用机理. 关键词： 双频率亚微秒脉冲 表面介质阻挡放电 连续漩涡     

Half-Width Integral Method for Gas Concentration Measuring in Tunable Diode Laser Absorption Spectroscopy

ABSTRACT

We analyze the influence of random errors and absorption shape fitting errors on gas concentration measurement in tunable diode laser absorption spectroscopy. We then propose a new data processing method according to the characteristic of random errors and fitting absorption shape. This method only uses the integral value within the half width at half maximum of the fitting absorption shape to determine the gas concentration in actual measurements. Meanwhile, the O₂ transition at 13,150.197 cm^?1 is selected to measure the O₂ concentration using this method. Compared with the traditional method, the method established in this paper can accurately measure O₂ concentration.     

分光技术在自由电子激光结合里德堡态氢原子飞行时间谱装置中的应用

本文描述了一种应用于自由电子激光结合高里德堡态氢原子飞行时间谱装置中的分光方法,以及该方法应用于小分子(如₂S)光解动力学研究中的必要性. 拉曼-α辐射(121.6 nm),用作H原子产物探测的激光,是在Kr/Ar气介质中利用四波混频产生的. 利用透镜对不同波长的光有不同的折射率,四波混频后的混合光在经过一片离轴的氟化锂透镜后,121.6 nm的激光将会与212.6和845 nm在空间上分开. 在激光到达反应中心前利用挡板挡住212.6和845 nm的激光,只让121.6 nm的光经过反应中心,从而消除212.6 nm激光产生的背景信号对实验的干扰. 结合自由电子激光,成功地研究了H₂S在122.95 nm波长下的光解动力学,采集到了产物时间飞行谱. 本文展示了转换得到的产物总平动能谱,解离机理与121.6 nm波长下的结果相似. 实验结果显示,该方法成功地解决了分子在VUV波段进行光解动力学研究的难题,消除了这些分子在紫外光波段因为强烈吸收而产生的背景信号.     

F+H2→HF+H反应的全量子态分辨的散射动力学研究

利用高灵敏度的氢原子里德堡飞渡时间谱方法研究了 F H_2→HF H 反应碰撞能在5.02kJ/mol 下的交叉分子束反应态态散射动力学.所有在时间飞渡谱中被观测到的谱峰可以归属为 HF 产物的振转态结构.还观测到了明显的 HF(v’=3)前向散射,以及少许的 HF(v’=2)前向散射.     

The high response organic ultraviolet photodetectors based on 2-TNATA as donor

Organic ultraviolet photodetectors (OUV-PDs) were fabricated utilizing 2-TNATA as an electron donor with Bphen and TPBi as electron acceptors. A high sensitivity of OUV-PDs to UV light was obtained in the range of 300–420 nm. The optimized OUV-PDs composed of Bphen as the acceptor offered a photocurrent density up to 336 µA/cm² at ?8 V with 365 nm UV light at a power of 1.2 mW/cm². The high response is attributed to the excellent electron transport ability of Bphen and the matched energy level between 2-TNATA and Bphen.     

Effects of a carbon convection field on large diamond growth under high-pressure high-temperature conditions

Large diamond crystals were successfully synthesized by a FeNi-C system using the temperature gradient method under high-pressure high-temperature conditions. The assembly of the growth cell was improved and the growth process of diamond was investigated. Effects of the symmetry of the carbon convection field around the growing diamond crystal were investigated systematically by adjusting the position of the seed crystal in the melted catalyst/solvent. The results indicate that the morphologies and metal inclusion distributions of the synthetic diamond crystals vary obviously in both symmetric and non-symmetric carbon convection fields with temperature. Moreover, the finite element method was applied to analyze the carbon convection mode of the melted catalyst/solvent around the diamond crystal. This work is helpful for understanding the growth mechanism of diamond.     

Effects of carbon convection field on large diamond growth under high-pressure high-temperature conditions

Large diamond crystals were successfully synthesized by FeNi-C system using temperature gradient method under high-pressure high-temperature conditions. The assembly of the growth cell was improved and the growth process of diamond was investigated. Effects of the symmetry of carbon convection field around the growing diamond crystal were investigated systematically by adjusting the position of seed crystal in the melted catalyst/solvent. The results indicate that morphologies and metal inclusion distributions of the synthetic diamond crystals vary obviously in both symmetric and non-symmetric carbon convection fields with temperature. Moreover, finite element method was applied to analyze carbon convection mode of the melted catalyst/solvent around the diamond crystal. This work is helpful for understanding the growth mechanism of diamond.     

非平衡磁控溅射沉积系统伏安特性模型研究

非平衡磁控溅射沉积系统的伏安特性对阴极溅射和薄膜沉积过程具有重要的影响.通过分析在常规磁控溅射沉积系统中非平衡磁场对于放电过程的影响，根据蔡尔得定律研究了非平衡磁场对磁控溅射沉积系统伏安特性影响的基本规律；根据模型和实验数据的对比证明模型正确表达了非平衡磁控溅射沉积系统中非平衡磁场对伏安特性影响的规律. 关键词： 等离子体 金属薄膜/非磁性 磁控溅射