The purpose of this paper is to evaluate the photoprotective efficiency of organic UV absorber Tinuvin 384 (T384) on the photocurable acrylate urethane coating under the accelerated weathering condition. The coatings without and with 2 wt.% T384 were examined by UV/CON accelerated weathering testing device. The aging of the coatings was assessed by IR and FE-SEM analysis as well as the measurement of mechanical and weight loss. The obtained results showed that due to the photoprotection of T384, the urethane acrylate coating was stable under the effect of accelerated weathering factors. After 48 cycles of aging, the CH and CNH groups, the abrasion resistance and the weight of the paint films containing 2 wt.% T384 were slightly decreased. Its surface was damaged just a little, while that of the coating without T384 was severely degraded.

This paper presents the development of simulated workplace neutron standard fields at the Institute for Nuclear Science and Technology with the 241Am-Be source moderated by polyethylene spheres with diameters of 15 cm and 30 cm. The characterization of the standard fields (in terms of neutron fluence rates and neutron ambient dose equivalent rates) was performed using Bonner sphere spectrometer system together with MAXED and FRUIT unfolding codes. The related quantities such as neutron dose equivalent-averaged energies and fluence-to-ambient dose equivalent conversion coefficients were also determined. The discrepancies of values are satisfied the standard uncertainty criteria as recommended by the International Standard Organization 12789 series. It implies that the simulated workplace neutron standard fields can be applied in the practical works for calibration purposes.

A novel liquid-phase precursor (LPP) method using precursor nanoparticles (PNs) is proposed to synthesize yttrium aluminum garnet nano-sized phosphor (Y3Al5O12:Ce3+, nano-YAG:Ce) at 1100-1500 degrees C for 5 h. The influences of the heat-treatment and morphology properties of the PNs on the luminescence properties of the nano-YAG:Ce phosphor were investigated. Nano-YAG:Ce phosphor with better morphology and high luminescence efficiency was obtained with heat-treatment of PNs at 1200 degrees C. With more heat treatment, the phosphor particles agglomerated more, and the emission intensity increased. The broad photoluminescence excitation (PLE) and photoluminescence (PL) spectra of the nano-YAG:Ce phosphor were centered at 341 nm and 466 nm, respectively, due to the 4f --> 5d energy transition. The nonsymmetrical emission spectra range of 470-750 nm was centered at 529.2 nm due to the 5d --> 4f energy transition of Ce3+. The nano-YAG:Ce, and micro-YAG:Ce phosphors synthesized by the LPP method using precursor microparticles (PMs) and PNs were investigated and compared.

Effect of ZnO nanoparticles on nanocomposite coatings based on R4152 and graphene oxide (GO) was studied.In presence of 2%wt. ZnO nanoparticle, abrasion resistance of coating increased by nearly 25% (from 75 to 92.9 L/mil) and temperature decomposition raised by 18oC. SEM images showed that nano ZnO can disperse homogenously in polymer matrix in presence of GO. Hence, photocatalytic activity of R4152/GO/ZnO nanocomposite coating was higher than that of R4152/ZnO nanocomposite coating. After 14 hours UV exposure, R4152/GO/ZnO nanocomposite coating can degrade over 80% methylene blue coated on its surface while 60% methylene blue was degraded by R4152/ZnO coatings.