Authors:B. Hu, Y. Song, L. Wang, Q. Zhang, J. Li, K. Wei, Y. Chen, and L. Zhang
Electronic stopping power of 19F in Ni, Pd and Gd was measured and compared to Mstar and SRIM calculation as well as experimental results published in literature.
It turns out that the present electronic stopping power agrees reasonably well with them.
Authors:D. H. Mu, J. Z. Du, D. J. Li, H. Q. Song, S. P. Yan, and Y. J. Gu
The comprehension of the behavior of radioactive nuclides in aquifer requires the study of the sorption processes of nuclides
in various geochemical conditions. The sorption/desorption of 65Zn(II) on surface sediments (0-2 cm) was investigated by batch method in sea water (pH 8.20, 35‰ salinity, filtered by 0.45mm)
at ambient temperature. The surface sediments were obtained from four stations around the Daya Bay of Guangdong Province (China),
where the first nuclear power station of China has been running from 1994. The sorption process is fast initially and around
39% average of sorption percentage (SP%) can be quickly obtained in 15 minutes for all the surface sediments. Then, the sorption
percentage becomes constant. In 30 days of contact time 79.6% sorption percentage and Kd=3.9. 103ml/g distribution coefficient was obtained. The value of Kdbecame constant, 4.0. 103ml/g, in contact time more than 120 hours. The distribution coefficient Kddecreases with increasing sediment concentration from 4.0 to 250 mg/l from 1.31. 104to 1.68. 103ml/g, respectively. Then the value of Kdgoes up to 5.38. 103ml/g with sediment concentration of 3000 mg/l. The desorption experiments suggest that the sorption of Zn(II) is irreversible
with a hyteresis coefficient of 66%.
Authors:B. Yan, H. X. Ma, N. N. Zhao, T. Mai, J. R. Song, F. Q. Zhao, and R. Z. Hu
As N-2′,4′-dinitrophenyl-3,3-dinitroazetidine (DNPDNAZ) is an important derivative of 3,3-dinitroazetidine, its thermal behavior was studied under 0.1 and 2 MPa by the differential scanning calorimetry (DSC) method. The results of this study show that there are one melting process and two exothermic decomposition processes. Its kinetic parameters of the intense exothermic decomposition process were obtained from the analysis of the DSC curves. The activation energy and the mechanism function under 0.1 MPa are 167.26 kJ mol−1 and f(α) = 3(1 + α)2/3[(1 + α)1/3− 1]−1/2, respectively, and the said parameters under 2 MPa are 169.30 kJ mol−1 and f(α) = 3(1 + α)2/3[(1 + α)1/3− 1]−1/2, respectively. The specific heat capacity of DNPDNAZ was determined using a continuous Cp mode of micro-calorimeter. Using the relationship between Cp and T with the thermal decomposition parameters, the time of the thermal decomposition from initialization to thermal explosion (adiabatic time-to-explosion, tTIAD), the self-accelerating decomposition temperature (TSADT), thermal ignition temperature (TTIT), critical temperatures of thermal explosion (Tb), and half-life (t1/2) were obtained to evaluate its thermal safety under different pressures.
Authors:H. X. Ma, B. Yan, Y. H. Ren, Y. Hu, Y. L. Guan, F. Q. Zhao, J. R. Song, and R. Z. Hu
3,3-Dinitroazetidinium (DNAZ) salt of perchloric acid (DNAZ·HClO4) was prepared, it was characterized by the elemental analysis, IR, NMR, and a X-ray diffractometer. The thermal behavior and decomposition reaction kinetics of DNAZ·HClO4 were investigated under a non-isothermal condition by DSC and TG/DTG techniques. The results show that the thermal decomposition process of DNAZ·HClO4 has two mass loss stages. The kinetic model function in differential form, the value of apparent activation energy (Ea) and pre-exponential factor (A) of the exothermic decomposition reaction of DNAZ·HClO4 are f(α) = (1 − α)−1/2, 156.47 kJ mol−1, and 1015.12 s−1, respectively. The critical temperature of thermal explosion is 188.5 °C. The values of ΔS≠, ΔH≠, and ΔG≠of this reaction are 42.26 J mol−1 K−1, 154.44 kJ mol−1, and 135.42 kJ mol−1, respectively. The specific heat capacity of DNAZ·HClO4 was determined with a continuous Cp mode of microcalorimeter. Using the relationship between Cp and T and the thermal decomposition parameters, the time of the thermal decomposition from initiation to thermal explosion (adiabatic time-to-explosion) was evaluated as 14.2 s.