We discuss the different physical processes that are important to understand the thermal X-ray emission and absorption spectra of the diffuse gas in clusters of galaxies and the warm-hot intergalactic medium. The ionisation balance, line and continuum emission and absorption properties are reviewed and several practical examples are given that illustrate the most important diagnostic features i...

In this research Calcium fluoride nanoparticles and its different amount of cerium ion dopant (5%and 10%) were prepared. The mentioned nanoparticle were studied by fourier transform infrared spectroscopy (FTIR) , X-ray diffraction (XRD), absorption and photoluminescence spectra (PL) and Scanning electron microscopy (SEM). The XRD patterns indicate a typical cubic fluorite structure and no other...

lithium disilicate nano-powders were synthesized via a mild condition hydrothermal reaction at 180 ºc for 48 and 72 h with a non stoichiometric1:2 li:si molar ratio in naoh aqueous solution using li2co3 and sio2.h2o as raw materials. the synthesized materials were characterized by powder x-ray diffraction (pxrd) technique and fourier transform infrared (ftir) spectroscopy. the xrd data showed t...

MgO-supported manganese carbonyl complexes were prepared by chemical vapor deposition of Mn(CO)5CH3 on partially dehydroxylated, high-area MgO powder. X-ray absorption spectra identify the resultant surface species, on average, as Mn(CO)4(Os)2 (where the two oxygen ligands are part of the MgO surface), and infrared spectra show that the chemisorption results from the reaction of Mn(CO)5CH3 with...

Aims. We investigate the signature of the photospheric albedo contribution in solar flare hard X-ray spectra, the effect of low energy cutoffs in electron spectra, and the directivity of hard X-ray emission. Methods. Using Ramaty High Energy Solar Spectroscopic Imager (RHESSI) flare data we perform a statistical analysis of spatially integrated spectra and positions of solar flares. Results. We...