能量倍增器法微波脉冲压缩

为了开展S波段能量倍增器脉冲压缩实验,对能量倍增器进行了冷测和热测工作,主要包括对能量倍增器的指标、参数的测量以及在高功率下对能量倍增器的输出功率、功率增益等参数的测量。实验中,完成了微波固态源系统的改造,研制了同步信号控制器,研究了输入输出脉冲宽度对输出峰值功率的影响,并对实验中可能的射频击穿问题进行了研究。在输入功率5 MW时,得到了功率增益7.122,输出脉宽260 ns,输出峰值功率35.35 MW。     

Analysis of Faraday–Michelson quantum key distribution system with unbalanced attenuation

Quantum key distribution(QKD) is a major research topic because it provides unconditional security. Unfortunately, many imperfections remain in QKD's experimental realization. The Faraday–Michelson(FM) QKD system is proposed to eliminate these imperfections using polarization. However, the long arm's phase modulator(PM) has an unexpected insertion loss, meaning that the state sent is no longer perfect. In this letter, we propose an alternative FM-QKD system structure, and analyze the security and key generation rate in comparison with the original system via different analysis methods. We find an obvious key rate improvement when the PM insertion loss is not extremely small.     

Wells-Dawson型杂多酸的制备及其在Baeyer-Villiger氧化反应中的应用

合成了Wells-Dawson结构的磷钨酸,用红外光谱、紫外光谱和X射线粉末衍射等方法对其结构进行了表征。将所制备杂多酸应用于催化环酮类化合物的Baeyer-Villiger氧化反应中,探讨了催化剂用量、H2O2的用量、反应温度、体系溶剂和反应时间对催化剂性能的影响。结果发现,所得催化剂对环酮类底物的催化氧化反应表现出良好的催化性能。在2-金刚烷酮的催化氧化中,以30%H2O2为氧化剂,在1,2-二氯乙烷溶剂中于80℃反应8 h后,2-金刚烷酮的转化率和产物2-金刚烷内酯的选择性都达到了99%以上。同时,催化剂具有一定的重复使用性。     

PNIPAM温敏微凝胶在生物医学领域中的应用研究

水凝胶因其良好的生物相容性及环境刺激响应性而在生物医学领域有着广泛的用途,但仍存在机械强度差、响应速度慢、不能生物降解等缺点。针对这些问题,特别是宏观水凝胶响应慢的问题,我们近年来以具有温度敏感性的聚N-异丙基丙烯酰胺(PNIPAM)微凝胶为基础,设计制备了一系列生物材料,分别应用于药物控释、生物传感以及组织工程等生物医学领域。我们设计制备了具有良好葡萄糖敏感性的PNIPAM微凝胶,实现了可自我调控的胰岛素可控释放。以PNIPAM微凝胶为基础,提出了新的聚合胶态晶体阵列光学传感方法,设计制备了多种可快速响应的新型生物光学传感器。实现了PNIPAM微凝胶的实时凝胶化,并将其发展成为一种新型的可注射细胞支架材料。进一步利用该体系的可逆性,提出了制备在药物筛选、肿瘤研究以及组织工程等领域有重要用途的多细胞球的新方法。     

PECVD介质膜性能研究

本文讨论了等离子体化学气相沉积(PECVD)方法生长的氮化硅薄膜的电学性能随生长条件的变化关系,得到了性能良好的氮化硅薄膜.结果表明这种介质膜达到了薄膜电致发光器件所要求的各个性能指标,是一种具有重要应用价值的介质薄膜材料.     

解析中考与圆锥相关的计算问题

近年来,与圆锥相关的计算问题在中考中时常出现,解答这类问题时,应明确圆锥侧面展开图是扇形,这个扇形的半径等于圆锥的母线长,弧长等于圆锥底面圆的周长,圆锥的侧面积等于侧面展开图扇形的面积,并灵活应运扇形的弧长、面积公式.下面以近几年中考题为例介绍一些和圆锥的侧面展开图有关的计算问题,供大家复复习时参考.     

微晶硅锗太阳电池本征层纵向结构的优化

采用射频等离子体增强化学气相沉积技术, 研究了辉光功率对微晶硅锗材料结构特性和光电特性的影响, 提出使用功率梯度的方法制备微晶硅锗薄膜太阳电池本征层. 优化后的微晶硅锗本征层不仅保持了晶化率纵向分布的均匀性, 而且形成了沿生长方向由宽到窄的渐变带隙分布, 使电池的填充因子和短路电流密度都得到了提高. 采用此方法制备的非晶硅/微晶硅锗双结叠层电池转换效率达到了9.54%.     

Tritium and helium analyses in thin films by enhanced proton backscattering

In order to study how to reliably perform quantitative tritium and helium analyses in thin film samples using enhanced proton backscattering(EPBS),several EPBS spectra for some samples consisting of non-RBS light elements(i.e.,T,4He,12C,16O,natSi),medium and heavy elements have been measured and analyzed using analytical SIMNRA and Monte Carlo-based CORTEO codes.The non-RBS cross sections needed in the CORTEO code are taken from the ENDF/B-Ⅶ.1 database and the calculations of SigmaCalc code and are incorporated into the CORTEO code.All non-RBS cross section data over the entire proton incident energy-scattering angle plane are obtained by interpolation.It is quantitatively observed that in EPBS analysis the multiple and plural scattering effects have little impact on the energy spectra for light elements and the RBS cross sections of light elements can be used in the SIMNRA code for dual scattering calculations.It is also observed that the results given by the CORTEO code are higher than the results of the SIMNRA code in the low energy part of EPBS spectra,and are in better agreement with the experimental data.Tritium and helium analyses in thin film samples using EPBS can be performed reliably when the multiple and plural scattering contributions are completely accounted.