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Thermal depoling behaviors of (K0.50Na0.50)0.94Li0.06NbO3 and (K0.50Na0.50)0.96Li0.04(Nb0.85Ta0.15)O3 ceramics possessing tetragonal crystalline structure at room temperature have been studied. By comparing the difference in these two compositions during annealing treatment, we provide visual evidence that different types of ferroelectric domain walls play different roles in the thermal depoling. The study results show that the drop in piezoelectric properties can be mainly attributed to the motion of 180o domain walls below the Curie temperature. When the thermal aging temperature is close to the Curie temperature, the reduction of piezoelectric properties is caused by the movement of 90o domain walls. The (K0.50Na0.50)0.96Li0.04(Nb0.85Ta0.15)O3 ceramic with fewer 180o domains shows very good thermal ageing stability from the low experimental temperature limit of −60 °C up to high temperatures close to TC.

Propylmethyl cellulose monoester of maleic acid (MAPMC) was synthesized with Propylmethyl cellulose and Maleic anhydride. A modified polyether-type superplastizer (PES) was prepared from ally polyoxyethylenether, Maleic anhydride, acrylic acid and MAPMC through a free radical polymerization. MAPMC and PES were recorded by FTIR. The fluidity of cement paste were investigated, the hydration process of cement for PES were characterized via Hydration Heat Tester. The results indicate that PES superplastizers can improve the fluidity of mortars and more capable of preventing slump loss, the hydroxy group of PES has no negative impact on cement hydration .

Four high-purity germanium 4-fold segmented Clover detectors have been applied in the experiment of neutron-rich nucleus 21N. The performance of those four Clovers have been tested with radioactive sources and in-beam experiments, and the main results including energy resolution, peak-to-total ratios, the variation of the hit pattern distribution in different crystals of one Clover detector with the energy of γ ray, and absolute full energy peak detection efficiency curve, were presented.

The β-delayed neutron and γ energy spectra taken from the decay of neutron-rich nucleus 21N were measured by using the β–γ and β – n coincidence detection method. Thirteen new neutron groups ranging from 0.28MeV to 4.98MeV and with a total branching ratio of 88.7 ± 4.2% were observed and presented. One γ transition with an energy of 1222keV emitted from the excited state of 21O, and four γ transitions with energies of 1674, 2397, 2780, and 3175keV emitted from the excited states of 20O were identified in the β decay chain of 21N. The β decay half-life for 21N is determined to be 82.9 ± 1.9 ms. The uncertainty of half-life is much smaller than the previous result.