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本文研究了有机溶剂加入后,表面活性剂增敏型体系微环境的变化。用核磁共振方法确定了有机溶剂分子与CTMAB胶束分子的作用部位。通过CTMAB溶液电导率测定及c.m.c值的测定,发现有机溶剂加入确实形成了一种新胶束。还研究了有机溶剂对显色反应速度的影响。并考察了体系微环境变化与相应显色液吸光度值的关系。我们的实验初步表明,有机溶剂的存在,改变了原有的CTMAB胶束,是增敏作用的重要因素,因而改变了发生显色反应的微环境。 相似文献
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Remedios González-Luque Manuela Merchán Piotr Borowski Björn O. Roos 《Theoretical chemistry accounts》1993,86(6):467-476
Summary Multiconfigurational electron correlation methods have been analyzed in order to theoretically compute the electron affinity (EA) of ozone. The near-degeneracy correlation effects, which are so important in O3 and O
3
–
, have been described using complete active space (CAS) SCF wave functions. Remaining dynamic correlation effects are computed using second-order perturbation theory (the CASPT2 method). The best calculated adiabatic value (including zero-point energy corrections), 2.19 eV, is about 0.09 eV larger than the experimental value. Comparative studies using size-consistent coupled pair functional approaches (CPF and ACPF) have also been performed. The harmonic frequencies in O
3
–
have been determined to be: 1=992, 2=572, and 3=879 cm–1, which gives a zero-point energy of 0.151 eV. 相似文献
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Marialuisa Russo Gabriella Poggi Maria Luisa Navacchia Mila D'Angelantonio Salvatore S Emmi 《Research on Chemical Intermediates》2006,32(2):153-170
Chemical radiolytic oxidation induced by OH addition on 1-(2-furan-2-yl-5-hydroxy-6-hydroxymethyl-[1,3]dioxan-4-yl)-ethan-1,2-diol
(sorbitylfurfural, SF) leads, in the presence of controlled amounts of oxygen, to a permanent functional modification of the
target molecule. The yield of conversion reaches 60% of the starting material. LC-MS analysis allowed the identification,
as final products, of carboxylic acids, butenal and hydroxy-furan derivatives in which the sugar chain remains unbroken, while
the furanic ring is attacked first by OH and then by oxygen, giving in succession an intra-/inter-molecular rearrangement
of the allylperoxyl radicals thus formed. The proposed oxidation of the furanic ring envisages the peroxyl intermediates undergoing
mono- and/or bi-molecular reactions; a reaction path has been outlined and is reported here. The presence of unsaturated bonds
in the final products could provide a further site for radical scavenger activity. Therefore, the fast reaction with O2 and the rearrangement of the produced peroxyl radicals to species, which are likely to be effective OH-capturers, reinforces
the antioxidant ability of SF. 相似文献
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Julia Vallejo Alejandro Pascual‐Álvarez Dr. Joan Cano Dr. Isabel Castro Prof. Dr. Miguel Julve Prof. Dr. Francesc Lloret Dr. J. Krzystek Prof. Dr. Giovanni De Munno Dr. Donatella Armentano Prof. Dr. Wolfgang Wernsdorfer Dr. Rafael Ruiz‐García Dr. Emilio Pardo 《Angewandte Chemie (International ed. in English)》2013,52(52):14075-14079
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与常规脉冲式主动声呐相比,连续波主动声呐能够提高目标回波的时间处理增益和目标信息更新速率。该文提出一种由正交多相码合成的连续发射波形,分析了发射信号和目标回波模型,设计了多通道匹配滤波器组完成回波检测。为了进一步提高接收机检测性能,提出了多通道非相干积累的处理方法。通过数值仿真,分析提出的连续波形的多普勒分辨性能和目标信息更新率。通过蒙特卡罗法获取接收机工作特性曲线,比较了脉冲式主动声呐和连续波主动声呐在均匀混响背景下对单目标检测性能的差异。仿真结果表明,该文设计的连续波波形具有较好的多普勒分辨性能,在均匀混响背景下,回波检测算法能够明显提高单个目标的探测能力。 相似文献
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The polarized electronic absorption spectra of a blue vanadium-doped zircon single crystal, grown by the flux method, has been studied by quantum chemical (CI) calculations in order to determine the position of the V4+ dopant in the zircon host structure. Particularly, the excitation energies and polarizations of V4+ occupying alternate positions, either the zirconium or silicon position or the interstitial site 16g, have been considered. It is concluded that the observed electronic absorption spectra and the color of zirconblue can only be explained if the V4+ chromophore is placed on the respective interstitial position. 相似文献
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介绍了借助计算机代数系统Maple实现全反射现象折射波瞬时行为动态展示的做法,讨论它的基础物理教学中的作用。 相似文献
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