[en] Using the NAXSUN technique developed at the JRC-Geel, the cross section functions for the neutron induced reactions ${}^{187}$Re(n,p)${}^{187}$W and ${}^{185}$Re(n,3n)${}^{183}$Re have been measured in the energy range between 13.08 MeV and 19.5 MeV. These data are the first experimentally obtained values for those nuclear reactions in this neutron energy range. Obtained results have been compared with existing evaluated data from ENDF/B-VII 0, JEFF 3.3, JEFF 3.2, BROND 3.1, JEF - 2.2, JENDL, ROSFO ND-2010, TENDL-2017, EAF-2010, FENDL-3.1c. The TALYS 1.9 and EMPIRE 3.2.3 calculations were performed using different available models and calculations using several semi-empirical existing formulas. A comparison between theoretical model calculations and experimental results was made.

[en] A new off-line timing method for PIN diode signals is presented which allows the plasma delay effect to be suppressed. Velocities of heavy ions measured by the new method are in good agreement within a wide range of masses and energies with velocities measured by time stamp detectors based on microchannel plates.

[en] We discuss the quality of heavy ions (HI) mass reconstruction in the wide range of HI energies and masses using Si PIN diodes for measuring both energy and time-of-flight. The results are based on the experimental data obtained at the IC-100 accelerator in the Flerov Laboratory of the JINR (Dubna, Russia). (paper)

[en] Amorphous powders of iron doped 3:2 mullite (3Al_2O_3⋅2SiO_2) were prepared by sol–gel combustion process using ethanol-water solutions of Al(III) nitrate, Fe(III) nitrate, TEOS and urea. Compositions up to 15 wt% of Fe_2O_3 were investigated. After combustion and heat treatment at 800 °C for 4 h, XRD analysis confirmed that the powders were amorphous. This is in agreement with the thermodynamic predictions that direct formation of mullite has not occurred during the aluminum nitrate – urea combustion reaction. XRD patterns of uniaxially pressed and sintered pellets at 1550 °C for 4 h revealed the crystal structure of orthorhombic mullite. The lattice parameters and unit cell volume increases as the mullite solid solutions were enriched by iron. The TGA/DSC analysis showed the reducing of crystallization temperature of iron doped mullites with increasing of iron content in reaction mixtures. The mullitization reaction is two-step process including formation of transient spinel phase below 1000 °C and mullite crystallization at temperatures about 1200 °C. The SEM micrographs of the sintered samples reveal elongated mullite grains with grain length up to 40 μm. Increasing of the iron content in the reaction mixture enhances the grain size and the grains become elongated and better packed increasing the density of sintered samples