We present here the results of our analysis of X-ray properties of Seyfert 2 galaxy NGC 3281, based on the observational data obtained by XMM-Newton and INTEGRAL within the energy ranges 0.2-12 keV and 20-150 keV, respectively. The XMM-Newton spectru
m of this object is presented for the first time. We show that fitting the X-ray spectrum of this galaxy with models based on the reflection from the disc with infinite column density yields non-physical results. More appropriate fit takes into account both transmitted and reflected emission, passed through a gas-dusty torus-like structure. Keeping this in mind, to model the inhomogeneous clumpy torus, we used the MYTorus model. Hence, we propose that the torus of NGC 3281 is not continuous structure, but it consists of separate clouds, which is in a good agreement with the results of near-IR observations. Using this assumption, we found that the torus inclination angle and the hydrogen column density are 66.98^{+2.63}_{-1.34} degrees and 2.08^{+0.35}_{-0.18}x10^{24} cm^{-2}, respectively. Also, the emission of the hot diffuse gas with temperature ~590 eV and warm absorption were detected.
X-ray observations of gravitationally lensed quasars may allow us to probe the inner structure of the central engine of a quasar. Observations of Q2237+0305 (Einstein Cross) in X-rays may be used to constrain the inner structure of the X-ray emitting
source. Here we analyze the XMM-Newton observation of the quasar in the gravitational lens system Q2237+0305 taken during 2002. Combined spectra of the four images of the quasar in this system were extracted and modelled with a power-law model. Statistical analysis was used to test the variability of the total flux. The total X-ray flux from all the images of this quadruple gravitational lens system is 6 x 10^{-13} erg/cm2/s in the range 0.2-10 keV, showing no significant X-ray spectral variability during almost 42 ks of the observation time. Fitting of the cleaned source spectrum yields a photon power-law index of Gamma=1.82+0.07/-0.08. The X-ray lightcurves obtained after background subtraction are compatible with the hypothesis of a stationary flux from the source.
