@article{shi_wang_yang_zhu_wu_2016,  title={Positron Annihilation Spectroscopy Study on Annealing Effect of CuO Nanoparticles},  volume={19},  ISSN={1516-1439},  url={https://doi.org/10.1590/1980-5373-MR-2015-0491},  DOI={10.1590/1980-5373-MR-2015-0491},  number={2},  journal={Materials Research},  publisher={ABM, ABC, ABPol},  author={Shi, Jianjian and Wang, Jiaheng and Yang, Wei and Zhu, Zhejie and Wu, Yichu},  year={2016},  month={Mar},  pages={316–321} }