Tritium and 14C are two most important radionuclides released from nuclear facilities to the environment, and 14C contributes dominant radiation dose to the population around nuclear power plants. This paper presents an overview of the production, pathway, species and levels of tritium and 14C in nuclear facilities, mainly nuclear power plants. The methods for sampling and collection of different species of tritium and 14C in the discharge gas from the stack in the nuclear facilities, atmosphere of the nuclear facilities and environment are presented, and the features of different methods are reviewed. The on-line monitoring methods of gaseous tritium and 14C in air and laboratory measurement methods for sensitive determination of tritium and 14C in collected samples, water and environmental solid samples are also discussed in detailed. Meanwhile, the challenges in the determination and speciation analysis of tritium and 14C are also highlighted.
Antioxidant packaging have been investigated for a very long time, since lipid oxidation may cause a lot of quality problems which are not just on lipids but also to other components of food during storage and transportation. Lipid oxidation of packaged food can be by partly excluded by adding antioxidants to the packaged food, however, in order to make sure sustain release of antioxidant in a relatively long term and avoid food safety problems concerned by consumers, controlled release antioxidant active packaging, on the basis of active packaging, has been introduced and investigated. Controlled release packaging (CRP) means that active compounds release from packaging materials in a controlled manner which offers a prolonged delivery of active compounds at predictable and reproducible release rate. This study focuses on three subject in regard to the realized methods of controlled release of antioxidants in food packaging, which include encapsulation of active compounds with a mesoporous matrix, modification of structure and composition of multilayer film, and preparation of hydrogel bio-based packaging polymers.