Coal and gas outbursts are geological disasters occurring in the process of coal mining that can cause serious casualties economic losses, among which CH 4 is main component mine gas. However, there still many seams around world dominated by CO 2 . Although frequency outburst accidents relatively low, very violent, notably difficult to control highly dangerous. The application hydration curing ...

Aims. The aims of our study are to improve the orbital elements of the giant, and to derive the spectroscopic orbit for the white dwarf companion. Spectral variations related to the 2006 outburst are also studied. Methods. We performed an analysis of about seventy optical and near infrared spectra of RS Oph that were acquired between 1998 and June 2008. The spectroscopic orbits have been obtain...

Coal and gas outbursts are a potentially fatal hazard that must be managed when mining gassy coal seams. Mining-induced stress plays an important role in outbursts, while elastic potential is accumulated to provide energy for outburst. In this study, large-scale true triaxial (LSTT) apparatus was developed conduct experiments understand the outburst mechanism mining-induced geo-stress evolution...

V4444 Sgr (Nova Sgr 1999) has been recently suggested to be a possible recurrent nova based on the detection of the preexisting dust, which may have been formed in a previous outburst. We examined this possibility using the available outburst observations, including the VSNET observations. We also noticed that this nova was recorded in the OGLE II public photometric database, which covered both...

We present seven separate Chandra observations of the 2001 superoutburst of WZ Sge. The high-energy outburst was dominated by intense EUV emission lines, which we interpret as boundary layer emission scattered into our line of sight in an accretion disc wind. The direct boundary layer emission was hidden from view, presumably by the accretion disc. The optical outburst orbital hump was detected...

We present new observations of the fundamental ro-vibrational CO spectrum of V1647 Ori, the young star whose recent outburst illuminated McNeil’s Nebula. Previous spectra, acquired during outburst in 2004 February and July, had shown the CO emission lines to be broad and centrally peaked—similar to the CO spectrum of a typical classical T Tauri star. In this paper, we present CO spectra acquire...

We have observed an outburst of the T Tauri star EX Lup in March 1994. We present both photometric (BVR) and spectroscopic (low and medium resolution) observations carried out during the decline after outburst. The star appears much bluer during outburst due to an increased emission of a hot continuum. This is accompanied by a strong increase of the veiling of photospheric lines. We observe inv...

Rossi X-ray Timing Explorer All Sky Monitor observations of SMC X-2 show that the source experienced an outburst in January to April 2000 reaching a peak luminosity of greater than ∼10 ergs s. RXTE Proportional Counter Array observations during this outburst reveal the presence of pulsations with a 2.37s period. However, optical photometry of the optical counterpart showed the source to be stil...

We present Spitzer observations of the unusual variable V838 Monocerotis. Extended emission is detected around the object at 24, 70 and 160 μm. The extended infrared emission is strongly correlated spatially with the HST optical light echo images taken at a similar epoch. We attribute this diffuse nebulosity to be from an infrared light echo caused by reprocessed thermal emission from dust heat...

We present near-infrared (1 2.5 μm) spectroscopic and photometric results of Nova V2615 Ophiuchi which was discovered in outburst in 2007 March. Our observations span a period of ∼ 80 days starting from 2007 March 28 when the nova was at its maximum light. The evolution of the spectra are shown from the initial P-Cygni phase to an emission-line phase and finally to a dust formation stage. The c...