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61.
The current technology of air‐filtration materials for protection against highly toxic chemicals, that is, chemical‐warfare agents, is mainly based on the broad and effective adsorptive properties of hydrophobic activated carbons. However, adsorption does not prevent these materials from behaving as secondary emitters once they are contaminated. Thus, the development of efficient self‐cleaning filters is of high interest. Herein, we report how we can take advantage of the improved phosphotriesterase catalytic activity of lithium alkoxide doped zirconium(IV) metal–organic framework (MOF) materials to develop advanced self‐detoxifying adsorbents of chemical‐warfare agents containing hydrolysable P? F, P? O, and C? Cl bonds. Moreover, we also show that it is possible to integrate these materials onto textiles, thereby combining air‐permeation properties of the textiles with the self‐detoxifying properties of the MOF material.  相似文献   
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Xiao  Wen  Chen  Cen  Zhang  Qian  Zhang  Qi-Hui  Hu  Yuan-Jia  Xia  Zhi-Ning  Yang  Feng-Qing 《Chromatographia》2015,78(21):1385-1393

Isoflavones are a very important group of natural products. This study investigated the separation of eight isoflavones, namely ononin, daidzin, genistin, biochanin A, formononetin, puerarin, genistein, and daidzein, from pueraria by micellar electrokinetic chromatography (MEKC) with different surfactants. The following micellar systems of MEKC were systematically compared for the analysis of these isoflavones: (1) a single surfactant comprising the anionic surfactant sodium dodecyl sulfate (SDS), the cationic surfactant hexadecyltrimethylammonium bromide, the neutral surfactant polyoxyethylene sorbitan monolaurate (Tween 20), and the ionic liquid-type surfactant (also a cationic surfactant) 1-dodecyl-3-methylimidazolium tetrafluoroborate (C12MIMBF4); (2) different single surfactants with 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) as an additive (modifier); and (3) mixed micelles of SDS + Tween 20 and C12MIMBF4 + Tween 20. Both SDS with BMImBF4 as additive and mixed micelles of SDS + Tween 20 had the highest separation efficiency for the eight investigated compounds. Furthermore, the SDS with BMImBF4 as additive was more stable (good repeatability of retention time and peak shape of analytes) than mixed micelles of SDS + Tween 20, which may be the result of a stabilizing effect of BMImBF4. Therefore, the final analytical conditions were 15 mM SDS added with 50 mM BMImBF4 in 30 mM sodium tetraborate (STB, pH 9.5) as running buffer; applied voltage, 20 kV; injection, 50 mbar for 5 s; cartridge temperature, 25 °C; compounds were detected at 260 nm. The developed method was fully validated (limit of detection, limit of quantification, intraday precision, inter-day precision, and recovery) and successfully applied to determine the eight analytes in three Radix Puerariae samples. The present study indicated that SDS with ionic liquids as additive in MEKC was suitable for the analysis of isoflavones.

  相似文献   
64.
制备型高效液相色谱法在天然产物的分离纯化中得到广泛应用。从制备型高效液相色谱法的技术分类及其在天然产物研究中的实际应用方面对目前国内外制备型高效液相色谱技术研究现状进行了综述,对其发展动态进行了展望。  相似文献   
65.
Particle concentration and particle size distribution curves have been measured for particle-laden jets of silica gel powder for different loading ratios and air velocities using a Laser Diffraction Method (LDM) and a tomography data transform technique. It was found that the mean particle size at the outer edge of the jet decreases with increasing gas velocity, and that the jet widens with decreasing particle concentration and increasing gas velocity.  相似文献   
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利用坐标变换的方法并结合保角映射技术,论文介绍了一种利用常规的各向同性材料来设计声波器件的方法.基于此理论,设计了二维声波隐身斗篷,并进行有限元模拟,证明了该器件的有效性.另外由于设计中没有利用材料共振的性质,所以器件是宽带有效的.该方法将有助于拓宽声波功能器件的设计,并为实验验证声波器件提供了可能.  相似文献   
68.
We advocate an effective field theory approach to anomalous couplings. The effective field theory approach is the natural way to extend the standard model such that the gauge symmetries are respected. It is general enough to capture any physics beyond the standard model, yet also provides guidance as to the most likely place to see the effects of new physics. The effective field theory approach also clarifies that one need not be concerned with the violation of unitarity in scattering processes at high energy. We apply these ideas to pair production of electroweak vector bosons.  相似文献   
69.
宽带可调谐掺Yb3+双包层光纤激光器的研究   总被引:3,自引:3,他引:0  
利用闪耀光栅构成可调谐Littrow外腔,对掺Yb3+双包层光纤激光器的波长调谐输出进行了实验研究.激光调谐输出波长范围70nm.针对光纤内的双折射效应对激光的输出功率的影响,实验中使用了在线光纤偏振控制器,从而有效地减小了调谐曲线的起伏及其与荧光谱的差别,并得到了窄线宽、线偏振、宽带调谐的激光输出.  相似文献   
70.
在一代Technicolor(TCI)和带有一个无质量的标量二重态(TCⅡ)模型下,计算荷电的哥尔斯通粒子对衰变B_c→D_sγ的贡献,并把它们同标准模型的计算相比较,发现哥尔斯通粒子对电磁企鹅图的贡献很大(TCI下),在TCⅡ下贡献较小;而对弱湮没图的贡献可以忽略不计,还对同位旋三重态粒子π+p的质量进行了约束。预言将来在LHC上能对不同模型下的分支比Br(Bc→Dsγ)的差异进行研究,进而对不同的模型进行检验。  相似文献   
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