Bi4V2O11/石墨烯异质结光催化剂的制备及其在降解抗体污染物中应用

发展和设计高效、廉价和稳定的光催化剂用于抗生素污染物降解仍然存在巨大的挑战。 本文通过一种便捷的水热方法制备了Bi₄V₂O₁₁/石墨烯复合材料并用于可见光下抗生素污染物光催化降解。 通过自由基追踪实验,确认了光催化降解过程中活性物质为h⁺和·OH基团。 根据实验结果,提出了相应的反应机理。 石墨烯的引入可以有效地促进光生电子-空穴对的分离,从而增强光催化活性。 该复合催化剂展现出良好的活性和稳定性。 该方法以石墨烯为载体制备了光催化降解材料,为高性能光催化剂的制备提供了参考。     

基于集合卡尔曼变换的东中国海声学 敏感区判定方法*

为改善海洋与水声环境预报质量,针对常规观测成本高、资料利用率低等问题,将适应性观测方法应用于海洋声学领域。结合海洋-声学耦合模式与集合卡尔曼转换敏感区诊断方法,以东中国海宫古海峡北部区域为验证区,计算并分析不同条件下海洋环境敏感区与声学敏感区分布,通过观测系统模拟试验验证适应性观测对验证区预报的提升效果。结果表明,两种敏感区位置随时间间隔增加均向验证区上游移动,海洋环境敏感区相比于声学敏感区分布更为集中,且平移特征更明显;对海洋环境敏感区和声学敏感区添加适应性观测均能提升海洋与水声环境的预报质量,提升效果随时间间隔增加而减小,在某种类型敏感区的适应性观测对相对应参数的预报质量提升效果优于对其他类型敏感区进行观测的效果。     

频率自适应最优权重阵列干涉条纹处理技术

考虑长基线水平阵列波束形成对声场模态呈现的滤波特征,建立了一种随频率改变滤波通带的阵列权矢量设计方法。基于简正波理论,结合声场波束形成特点,在分析了常规波束形成信号LOFAR谱图干涉条纹的清晰度和条纹结构不同于单水听器输出信号条纹现象基础上,采用线性等式约束的二次优化模型,给出了一种频率自适应的最优权重估计。数值仿真验证和试验数据分析表明,利用该方法设计的最优权重阵列波束处理,可以滤波出SRBR(Surface-Reflected Bottom-Reflected)或N-SRBR(Non-Surface-Reflected Bottom-Reflected)模态组成的波束形成信号,信号谱图干涉条纹斜率与理论分析基本一致。     

基于MEMS姿态传感器的声矢量传感器设计

针对声矢量传感器姿态变化难以准确测量导致目标测向精度低的现状,设计一种微型MEMS姿态传感器,并将其封装在声矢量传感器内部,实现基于MEMS姿态传感器的声矢量传感器设计。首先根据声矢量传感器姿态测量与校正原理,采用四元数姿态解算方法及扩展卡尔曼滤波器设计MEMS姿态传感器,并对其进行姿态精度测试;然后基于MEMS姿态传感器进行声矢量传感器样机设计、制作、参数测试;最后对样机进行了海上实验,结果表明,通过姿态校正后声矢量传感器目标方位估计精度与GPS推算方位精度一致,验证了利用MEMS姿态传感器设计声矢量传感器的可行性。     

Highly Catalytic Enantioselective Addition of Diethyl Zinc to Aldehydes and Chalcone in the Presence of Chiral Ligands

Catalytic asymmetric carbon-carbon bond formation is one of the most important reactions and have attracted much attention to develop more efficient enantioselective C-C formation methods in organic synthesis. In this field, asymmetric addition of diethylzinc to aldehydes[1] and conjugate addition to enones[2] have drawn special interests and have been greatly developed. Regardless of it, much spaces in these areas still exist, so it needs more extensive and intensive researches for the purpose of as follows: (1) attaching ligands to a polymer for the easy separation of the catalysts so as to be able to allow very efficient recovery and reuse of the catalysts, and the possibility of carrying out the desired transfomation in continuous mode in a flow reactor, etc., (2) searching for novel chiral catalysts with such features as more suitable for more extensive substrates varieties, and more convenient and economical as well as possessing applicable prospect, and so on. Here we report some works in these areas done in our laboratory.     

Preparation and Characterization of Zirconia-Magnesia Support Modified by Alkylphosphonic Acid for Liquid Chromatography

Interest in zirconia as a chromatography support has increased considerably recently because of its chemical inertness and its promise as a useful support. We have reported the preparation of spherical zirconia and characterization of its chromatographic behavior. However, the zirconia was found unsatisfactory for its chromatographic efficiency, probably owing to the poor pore structure of it. In this paper, we for the first time report the preparation of alkylphosphonic acid modified zirconia-magnesia stationary phase, and characterization of its structure and chromatographic behavior.     

采用可见光源和分划板快速装调激光光路

 分析了激光测量光路的特点和装校要求,给出了采用可见光源、分划板装校激光光路的原理。以预放测量模块为例,介绍了装校的流程及装校中的注意事项,分析了装校所能达到的精度,并用内调焦望远镜进行了装校精度检查。结果表明,采用可见光源、分划板装校的激光光路透镜光轴正过心的偏心极限误差小于等于0.07 mm,光轴倾斜极限误差小于等于25″。     

Equivalent properties of single event burnout induced by different sources

The experimental results of single event burnout induced by heavy ions and 252Cf fission fragments in power MOSFET devices have been investigated. It is concluded that the characteristics of single event burnout induced by 252Cf fission fragments is consistent to that in heavy ions. The power MOSFET in the "turn-off" state is more susceptible to single event burnout than it is in the "turn-on" state. The thresholds of the drain-source voltage for single event burnout induced by 173 MeV bromine ions and 252Cf fission fragments are close to each other, and the burnout cross section is sensitive to variation of the drain-source voltage above the threshold of single event burnout. In addition, the current waveforms of single event burnouts induced by different sources are similar. Different power MOSFET devices may have different probabilities for the occurrence of single event burnout.