Thermal decomposition study of dihydroxylammonium 5,5 0 -bistetrazole-1,1 0 -diolate (TKX-50) was investigated by using TG-DTG and TG-IR-MS and found that N 2 , N 2 O, NH 3 and H 2 O were the main products during the decomposition process. The kinetic parameters (Ea = 138.96 kJ mol -1 and A = 10 12.93 s -1 ) for thermal decomposition reaction of TKX-50 were obtained from DSC profile by differential method and integral method, and the nonisothermal kinetic equation of the exothermic process was da=dT ¼ ð10 12:93 =bÞ3ð1 À aÞ½À lnð1 À aÞ 2=3 expðÀ1:6713  10 4 =TÞ; suggesting that the main exothermic decomposition reaction mechanism of TKX-50 was classified as Avrami-Erofeev equation. In addition, the theoretical detonation velocity (D = 8804 m/s) of TKX-50 at 298.15 K was calculated by a simple method. Finally, the safety parameters of TKX-50 (25 kg) including time to maximum rate under adiabatic conditions and self-accelerating decomposition temperature were calculated to be 142.12 and 129.01°C by using AKTS software.
A series of novel SrLu 2 O 4 : x Ho 3+ , y Yb 3+ phosphors (x=0.005-0.05, y=0.1-0.6) were synthesized by a simple solid-state reaction method. The phase purity, morphology, and upconversion luminescence were measured by X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectroscopy. The doping concentrations and sintering temperature were optimized to be x=0.01, y=0.5 and T=1400°C to obtain the strongest emission intensity. Under 980 nm laser diode excitation, the SrLu 2 O 4 :Ho 3+ , Yb 3+ phosphors exhibit intense green upconversion (UC) emission band centered at 541 nm ( 5 F 4 , 5 S 2 ? 5 I 8 ) and weak red emission peaked at 673 nm ( 5 F 5 ? 5 I 8 ). Under different pump-power excitation, the UC luminescence can be finely tuned from yellow-green to green light region to some extent. Based on energy level diagram, the energy-transfer mechanisms are investigated in detail according to the analysis of pump-power dependence and luminescence decay curves. The energy-transfer mechanisms for green and red UC emissions can be determined to be two-photon absorption processes. Compared with commercial NaYF 4 :Er 3+ , Yb 3+ and common Y 2 O 3 :Ho 3+ , Yb 3+ phosphors, the SrLu 1.49 Ho 0.01 Yb 0.5 O 4 sample shows good color monochromaticity and relatively high UC luminescence intensity. The results imply that SrLu 2 O 4 :Ho 3+ , Yb 3+ can be a good candidate for green UC material in display fields. K E Y W O R D S energy transfer, phosphor, rare earths, SrLu 2 O 4 , upconversion
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.