Spectral relationship of photoinduced refractive index and absorption changes in fulgide films

Fulgides are one kind of organic photochromic compound, which are famous for their thermal irreversibility. In this report, from the difference spectra of the absorption A() of one kind of pyrrylfulgide, the spectral refractive index change n() was calculated by the Kramers-Kronig relation (KKR), and a good correlation of theoretically derived values and the experimental values of the n measured by a modified Michelson interferometer was found. Further, it is demonstrated that it was possible to calculate the spectral dependence of diffraction efficiency from the easily accessible absorption changes. This method will be a useful tool for the characterization and optimization of fulgide films. The results show that the diffraction efficiency is high at 488 and 750 nm, where the absorption is very small, so we can realize non-destructive reconstruction.

SULFUR IX TO XIII SPECTRAL MEASURMENTS BETWEEN 170 AND 500Å

This paper reports laboratory measurements of the spectrum of highly ionized sulfur. The spectrum of S Ⅸ–S ⅩⅢ has been observed in the wavelength range 170–500 Å. A total of 54 lines have been measured. Forty-two of them have been classified as 2s22pk–2s2pk+1and 2s2pk–2pk+1 transitions. Twelve other lines have been ascribed to 2s–2p,4p–5s,5p–6s,5d–6p, and 6p–8d transitions. These spectral lines have been identified, among which 22 are new and accurately measured. The analysis of the spectra was based on a comparison with other experimental results and calculated values.

由QCD求和规则计算s夸克质量

简要回顾了量子色动力学求和规则在计算s夸克质量方面的应用。结合Dominguez,Gend和Paver的工作,重新考虑渐近自由阈以下的谱函数后,计算了s夸克的质量,得到s夸克的跑动质量-ms(1 GeV)=219 MeV。讨论了影响计算结果精度的可能因素。

QCD求和规则与强子物理

量子色动力学(QCD)求和规则是强子物理研究中的一种重要的非微扰方法,已经成为强子物理与核物理研究中有力的工具。简单介绍了QCD求和规则的基本概念、方法与应用,特别讨论了QCD求和规则近年来的发展和与之相关的一些前沿问题。