含氮芥双-(亚苄基)环烷酮的合成、晶体结构及其体外光动力抗肿瘤活性

为构建光动力治疗与化疗协同抗肿瘤先导化合物,基于药效团拼合原理,设计合成了含氮芥双-(亚苄基)环烷酮化合物3a~3c及对比的双-(亚苄基)环烷酮化合物3d~3f,并经核磁共振波谱仪(NMR)、高分辨质谱HRMS(ESI-MS)、X射线衍射仪(XRD)及傅里叶变换红外光谱仪(FTIR)等技术手段对其进行了结构和性质表征。采用噻唑蓝(MTT)法考察了他们对A549(人肺腺癌细胞)和Hep G2(人源肝癌细胞)的光毒性。结果表明,大部分化合物对两株受试细胞株表现出了一定的光毒性,尤以化合物3a对Hep G2光毒性的半抑制率(IC50)达到2. 0 nmol/m L,值得进一步研究。运用Gaussian09软件,在B3LYP和6-311G+基组水平上对化合物3a和3d进行了量子化学计算并得到其优化构型和分子轨道能量,从前沿轨道能量分析了化合物的结构特征和抗肿瘤活性的构效关系。     

Focusing of Time Reversal Lamb Waves and Its Applications in Structural Health Monitoring

The focusing of time reversal acoustic fields for dispersive and multimodal Lamb waves is theoretically investigated and experimentally verified. It is demonstrated that the time reversal Lamb wave signal will reach the maximum amplitude when the observation point is located at the damage location. Based on the time reversal focusing theory, a damage imaging method is proposed for structural health monitoring using Lamb waves. The experiments employ a transducer network consisting of four piezoelectric transducers as actuators and as well sensors for excitation and measurement of Lamb waves. The results show that this method is able to accurately predict damage location and provides an estimation of the possible area even for damage close to one of the transducers or even slightly outside the transducer network.     

新型氧钒(IV)席夫碱配合物［VO(dtbsal-met)(phen)和VO(naph-met)(phen)］的合成及其抗肿瘤活性

以L-蛋氨酸（met）, 1,10-邻菲啰啉（phen）和3,5-二叔丁基水杨醛（dbsal）［或2-羟基-1-萘醛（naph）］为原料,经胺醛缩合反应合成了两个新型的氧钒(IV)席夫碱配合物［VO(dtbsal-met)(phen)（1）和VO(naph-met)(phen)（2）］,其结构经IR, HR-ESI-MS,摩尔电导和X-射线单晶衍射表征。1（CCDC：1 429 158）和2（CCDC：1 429 159）分别属单斜晶系和三斜晶系。用MTT法研究了1和2对人肺腺癌细胞（A549）和人源肝癌细胞（HepG2）的体外抗肿瘤活性。结果表明：1和2对A549和HepG2均表现出一定的抑制活性。     

基于时间反转理论的聚焦Lamb波结构损伤成像

从理论和实验上研究了时间反转法在频散和多模式的Lamb波结构健康检测方面的应用.当Lamb波在包含有损伤的板类结构中传播时,损伤的存在表现为一个被动波源.采用分布式传感器网络,基于传递函数的观点,通过推导由损伤这个被动波源产生的时间反转波场幅值的表达式,证实了当观察点位于损伤位置时,时间反转波场的幅值最大.为验证时间反转方法的聚焦效应,提出了一种适合于分布的激励/接收传感器网络的成像方法,该方法可以对损伤定位并近似确定损伤尺寸.结合有限元的实验结果显示了Lamb波检测信号的能量可在损伤处聚焦,表明时间反转     

A time reversal damage imaging method for structure health monitoring using Lamb waves

This paper investigates the Lamb wave imaging method combining time reversal for health monitoring of a metal-lic plate structure.The temporal focusing effect of the time reversal Lamb waves is investigated theoretically.It demonstrates that the focusing effect is related to the frequency dependency of the time reversal operation.Numerical simulations are conducted to study the time reversal behaviour of Lamb wave modes under broadband and narrowband excitations.The results show that the reconstructed time reversed wave exhibits close similarity to the reversed nar-rowband tone burst signal validating the theoretical model.To enhance the similarity,the cycle number of the excited signal should be increased.Experiments combining finite element model are then conducted to study the imaging method in the presence of damage like hole in the plate structure.In this work,the time reversal technique is used for the recompression of Lamb wave signals.Damage imaging results with time reversal using broadband and narrowband excitations are compared to those without time reversal.It suggests that the narrowband excitation combined time reversal can locate and determine the size of structural damage more precisely,but the cycle number of the excited signal should be chosen reasonably.     

微波萃取/气相色谱-质谱测定土壤中的多氯联苯

分别对多氯联苯的微波萃取条件进行了优化。优化后的分析条件为微波功率1200 W,萃取温度115℃,萃取时间20 min,萃取溶剂为V(正己烷)∶V(丙酮)=1∶1。方法的检出限为20~30 ng/g,线性范围40~4000 ng/mL(多氯联苯总量),相关系数均大于0.9990,样品基体加标回收率为92.2%~115%,相对标准偏差为9.4%(n=6)。     

采用单个压电传感器的单模式兰姆波激发频率的选择

考虑了压电传感器(PZT)与板之间的耦合作用,从理论上研究了单个压电传感器激发时产生单模式兰姆波的频率调节方法,实验给出了模式选择在兰姆波结构健康监测中的应用. 在板材、板厚以及PZT尺寸一定的情况下,从理论上能够预测到作为频率函数的各兰姆波模式的幅值变化. 根据某特定兰姆波模式的幅值最大而其他模式幅值相对最小时所对应的频率,即可识别出该兰姆波模式优化的激发频率. 数值仿真验证了理论的有效性以及单模式兰姆波选择的可能性. 在不同的激发频率下,分别激发了优化的A0 模式,优化的S0模式以及共存的A0和S0模 关键词： 兰姆波 压电传感器 激发频率 结构健康监测