尾式卟啉铁的磁圆二色（MCD）谱研究

在无氧条件下测定了一种新型尾式卟啉铁[5-邻-(4-二甲氮基丁酰胺)苯基-10,15,20-三苯基卟啉铁(Ⅱ)及其含N配体、CO、NO轴向加合物的磁圆二色(MCD)光谱,考察了轴向混合配位时MCD光谱的变化.     

CO在1. 578 μ m的可调谐二极管激光光谱信号小波去噪研究

研究了一氧化碳(CO)近红外波段直接吸收和波长调制信号去噪处理算法。从HATRAN数据库中得到CO气体的吸收信号作为仿真数据,提取直接吸收信号、1-f和2-f解调信号作为原始信号,研究了不同小波基以及不同的分解层数对叠加高斯白噪声的光谱信号去噪的效果。最后利用基长为0.95 m有效光程为55.1 m的Herriott型多光程池对CO在1.578 μm处的第二泛频带P(4)吸收谱线信号进行测量和信号处理,与原始信号相比,经过信号处理过的直接吸收、1-f和2-f解调信号的信噪比都提高1～2个数量级;通过选择不同小波基和优化小波变换层数,增加了系统的抗干扰能力。     

Ultrafast Decay Dynamics of N-Ethylpyrrole Excited to the S1 Electronic State: A Femtosecond Time-Resolved Photoelectron Imaging Study

N-ethylpyrrole is one of ethyl-substituted derivatives of pyrrole and its excited-state decay dynamics has never been explored. In this work, we investigate ultrafast decay dynamics of N-ethylpyrrole excited to the S₁ electronic state using a femtosecond time-resolved photoelectron imaging method. Two pump wavelengths of 241.9 and 237.7 nm are employed. At 241.9 nm, three time constants, 5.0±0.7 ps, 66.4±15.6 ps and 1.3±0.1 ns, are derived. For 237.7 nm, two time constants of 2.1±0.1 ps and 13.1±1.2 ps are derived. We assign all these time constants to be associated with different vibrational states in the S₁ state. The possible decay mechanisms of different S₁ vibrational states are briefly discussed.     

混合金属络合物羟基镍铝交联蒙托土的合成

用取代法和共聚法合成了一系列羟基镍铝交联蒙托土。(27)~Al-NMR,UV谱表明两种合成方法都可以得到具有Kessin结构的羟基镍铝柱。取代法合成的交联蒙托土具有均一的(001)面衍射(d_(001)约1.80nm),而共聚法的样品有两种羟基镍铝柱支撑着层间,分别在1.80nm和1.55nm附近产生复合(001)面衍射。用高温老化处理可改善交联蒙托土的热稳定性。经过处理的样品在700℃焙烧后仍可保持稳定,与不经处理的样品相比,热稳定性提高200℃以上。     

Synthesis of Multishell Carbon Nanotube Composites via Template Method

Multishell nanotubes of polyaniline and carbon were synthesized via a template approach. A thin layer of MnO₂ coated on carbon nanotubes acts as a reactive template for the consequent formation of the polyaniline coating. The polyaniline-carbon nanotubes show enhanced dispersibility in water and can be possibly used as a functional material of electrochemical capacitors with improved performance. The general method operates by coating carbon nanotubes on functional materials such as poly (3,4-ethylenedioxythiophene), polypyrrole, silica, and carbon.