... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

... The variability of the spectrum of the optical component of the IR-source IRAS01005+7910 was discovered for the first time in the BTA spectra [1]. ... The spectral features include absorptions that form in near-photospheric layers, narrow envelope emissions, and emission-absorption profiles that form in photosphere-to-envelope transition layers (the wind). ... Discovery of spectral variation in the optical counterpart of IRAS01005+7910. ... Dashed line - envelope curve of all the SiII 5979 profiles ...