催化合成4, 4'－亚甲基二苯基二氨基甲酸酯反应中生成的副产物研究

确定了4,4'－亚甲基二苯胺与碳酸二甲酯合成4,4'－亚甲基二苯基二氨基甲酸酯反应中生成的副产物的结构，并在此基础上给出了各副产物的形成机理     

Structural Crack Identification Based on the Variational Mode Decomposition北大核心CSCD

In order to enrich the bridge damage detection method and further improve the accuracy of bridge damage identification, a detection method for simply supported beams with cracks under dynamic loads was proposed not based on the complete finite element model. Under the premise of not blocking traffic, the method only needs to analyze and deal with the acceleration responses of the simply supported beam span, which reduces the mounting, dismounting and maintenance of sensors in practical engineering. At the same time, based on the model, an analytical formula of the acceleration at the midspan of the simply supported cracked beam was derived. Based on the theoretical derivation, the instantaneous energy and the mean energy difference were constructed through the variational mode decomposition and the Hilbert transform, and these 2 crack identification indexes were used to effectively identify small cracks with a crack depth ratio of only 5%. Then the influences of different wheel loads, environmental noises and damage degrees on detection results were studied. The results show that: ① the instantaneous frequency has a better recognition effect for crack positions; ② the mean energy difference is sensitive to crack depth ratio δ and the wheel load magnitude; ③ this method has strong noise robustness. © 2022 Editorial Office of Applied Mathematics and Mechanics. All rights reserved.     

国内首创的SPIMS-1000在线挥发性有机物质谱仪

概述了国内首款具有完全自主知识产权的商品化在线挥发性有机物质谱仪(SPIMS-1000)。SPIMS-1000融合了膜富集、紫外光单光子软电离(SPI)和反射式飞行时间质谱等多种技术,实现了对挥发性有机物(VOCs)及半挥发性有机物(SVOCs)的在线定性定量分析。对其基本原理、仪器设计、分析参数及应用进行了介绍。     

用于受激光散射实验的光学多道分析器

使用自制的以ＣＣＤ成像器件为探测器的简易光学多道分析器完成了受激光散射谱的系集与处理。该多过分析器空间分辨率１４μｍ，灵敏度０．１ＬＸ，给出了装置的设计以及所得到的谱图     

4-氨基邻苯二甲酰亚胺衍生物作为荧光探针的应用

介绍了近年来4-氨基邻苯二甲酰亚胺(AP)类荧光探针在主-客体化学、金属离子测定、溶剂化动力学及各种有序分子聚集体(如胶束、反胶束)性质研究方面的进展。     

氩原子近LⅡ,Ⅲ边结构和振子强度密度

在入射电子能量2500eV，平均散射角为0°的条件下测量了氩原子内壳层2p电子激发和电离的高分辨电子能量损失谱，确定了分立态的有效量子数和电离边的能量．同时确定了两组分立跃迁和电离连续区的振子强度密度． 关键词：     

超导薄膜螺旋生长结构对临界电流密度的影响

本文用扫描隧道电子显微镜和原子力显微镜观察了不同实验条件一利用激光沉积技术制备的ＹＢｑａ２Ｃｕ３Ｏ７－ｘ超导薄膜的微观结构，并分析了薄膜细胞与超导电性的关系。螺旋生长结构能减少薄膜中的弱连结和在薄膜中形成磁通钉扎中心，因此使超导薄膜的临界电流密度比同类超导体材大得多。     

凝聚态中的维度性渡越

简要综述了凝聚态中的维度性渡越现象，其中包括整数之间的渡越和整数维与分数维的之间的渡越，讨论了维度性越对于凝聚态物质的物理性质的影响。     

超声促进胶体聚沉作用的研究

本文研究了超声促进胶体聚沉作用，选用了具有代表性的原糖溶液和老抽酱油为研究对象，研究结果表明，适宜的超声参数能十分显著加速胶体的聚沉，为物理场手段降去胶体提供一个新的途径。