Liu, L.; Li, S.; He, X. N.; Huang, X.; Zhang, C. F.; Fan, L. S.; Wang, M. X.; Zhou, Y. S.; Chen, K.; Jiang, L.; Silvain, J. F.; and Lu, Yongfeng, "Flame-enhanced laser-induced breakdown spectroscopy" (2014 Abstract: Flame-enhanced laser-induced breakdown spectroscopy (LIBS) was investigated to improve the sensitivity of LIBS. It was realized by generating laser-induced plasmas in the blue outer envelope of a neutral oxy-acetylene flame. Fast imaging and temporally resolved spectroscopy of the plasmas were carried out. Enhanced intensity of up to 4 times and narrowed full width at half maximum (FWHM) down to 60% for emission lines were observed. Electron temperatures and densities were calculated to investigate the flame effects on plasma evolution. These calculated electron temperatures and densities showed that high-temperature and low-density plasmas were achieved before 4 µs in the flame environment, which has the potential to improve LIBS sensitivity and spectral resolution.

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A polyphosphonate (PDPA) flame retardant that contains phenyl phosphonic dichloride and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide groups, has been synthesized. The flame retardant was introduced into epoxy resins (EP) and cured by 4,4’-diamino diphenylmethane. The vertical burning, limited-oxygen index and cone calorimeter tests reveal that the PDPA can enhance the flame-retardant properties of the EP significantly. With only a 4 wt% PDPA loading, the EP composites achieved a limited-oxygen index value of 33.4% and a V-0 rating in the vertical burning test, and the peak heat release rate and total heat release were decreased by 40.9% and 24.6%, respectively. The thermal properties and gas pyrolysis products of the EP composites were evaluated by thermogravimetric analysis and thermogravimetric analysis-Fourier transform infrared spectroscopy, and the morphology and structure of residual char were characterized by scanning electron microscopy, Flourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. To explain the combined effects of the condensed and gas phases, modes of the flame-retardant action are proposed.

The design goals of a spectropolarimetric system are higher spectropolarimetric resolution， a smaller and lighter system， and static measurement of the full Stokes spectrum. Therefore， the spatially modulated heterodyne interference spectropolarimetric system， which combines the technologies of intensi• ty modulation and spatial heterodyne was proposed. While the process of all mathematical derivation was displayed， the principle and structure of the system were presented and a theoretical analysis of the interfer• ogram data acquisition and full Stokes parameters demodulation restoration was carried out. The matching modulator module was designed and a complete design example was finished based on the parameters of the spatial heterodyne spectrometer used. A principle experimental device of spatially modulated hetero• dyne interference spectropolarimetric system was established in the laboratory， and the feasibility of the 文章编号 1004-924X (2023)07-0992-08