  In this study we present the analysis of six solar flare events that occurred
in 2022, using new data from the third-generation Miniature X-Ray Solar
Spectrometer (MinXSS), also known as the Dual-zone Aperture X-ray Solar
Spectrometer (DAXSS). The primary focus of this study is on the flare's "onset
phase", which is characterized by elevated soft X-ray emissions even before the
flare's impulsive phase. We analyze the temporal evolution of plasma
temperature, emission measure, and elemental abundance factors during the flare
onset phase, by fitting the DAXSS spectra with the Astrophysical Plasma
Emission Code (APEC) model. The model fitting results indicate that the
flaring-plasma is already at a high temperature (10-15 MK) during the onset
period. The temperature rises during the onset phase, followed by a decrease
and subsequent increase during the impulsive phase. Elemental abundance factors
show a trend of falling below pre-flare values during the onset phase, with
some recovery before the impulsive phase. During the impulsive phase, the
abundance factors decrease from elevated coronal values to about photospheric
values. We also analyze images from the 193 Angstrom channel of the Atmospheric
Imaging Assembly (AIA), highlighting the formation or brightening of coronal
loop structures during the onset phase. Two distinct onset loop configurations
are observed which are referred to as 1-loop and 2-loop onsets. Both DAXSS and
AIA observations indicate that the flare onset phase exhibits similar hot
coronal plasma properties as the impulsive phase, suggesting that the onset
phase may act as a preconditioning effect for some flares.
