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A new glass solidification process aims at radioactive iodine waste was explored in order to reduce the possible harm to environment. Samples with different iodine content in silver-coated silica gel were pretreated by hydration device at 300 °C and then sintered at relatively low temperatures (500, 550 and 600 °C). XRD results show that AgI is mainly chemically fixed in the glass network with some AgI particles being physically wrapped by the glass. Moreover, as the sintering temperature reached to 550 °C, B element crystallized. SEM-EDS results show that Ag and I elements are enriched, while the other elements are evenly distributed. AFM results showed that the sample surface becomes rougher as the iodine content increases in the silver coated silica gel. The FT-IR results show that the structure of the sintered sample is mainly composed of [BiO3], [BiO6] and [BO3]. This study provides a new sintering method by hydration device for the treatment of radioactive iodine waste.

In order to find a rapid, efficient, safe and reliable treatment technology for radioactive contaminated soil, the microwave sintering method was used to sinter the simulated radioactive contaminated soil with different CeO

The disposal of radioactive iodine waste is a top priority for the nuclear industry. This work mainly studies the replacement of crystalline material (SiO2) in silicate-based material with amorphou...

In the field of radioactive waste immobilization, the investigation of irradiation stability is of considerable importance. In this study, uranium-contaminated soil samples were irradiated by 1.5 MeV Xe20+ ions with fluences ranging from 1 × 1012 to 1 × 1015 ions/cm2. Xe20+ heavy-ion radiation was used to simulate the self-irradiation of actinide nuclides. The uranium-contaminated soil samples were sintered via microwaves. Grazing incidence X-ray diffraction results showed that irradiation can cause crystallization of the sample. After irradiation, the Vickers hardness of the samples decreased slightly. Comparative analysis showed that the sample had good radiation resistance, and the leaching rate (28 d) of the sample increased slightly after irradiation, but the overall performance was stable. Our investigation reveals the corresponding mechanism of uranium-contaminated soil irradiation of 1.5 MeV Xe20+ ions.

The immobilization of iodine waste is a challenge in the field of nuclear waste. In this work, iodine waste (silver-coated silica gel with different iodine loadings) was immobilized at low-sintering temperatures (500, 550, and 600 ​°C). XRD represented that the crystallized phases of the sintered matrix consist of AgI and B2O3. The crystallization behavior of boron can be found as the sintering temperature increased from 500 ​°C to 600 ​°C. FT-IR results proved that in the process of crystallization, part of the microstructure related to B–O stretching transformed from [BO4] to [BO3] units, which benefits low-temperature iodine waste immobilization due to the bonding energy of [BO3] is higher than that of [BO4]. Our work reveals the B-related microstructure transition in low-temperature immobilization iodine waste.

The effect of surface nanostructuring via reactive O 2 /Ar plasma etching on the S-band radio-frequency (RF) field emission performance for nitrogen-doped nanocrystalline diamond (N-NCD) films was preliminarily investigated. A transition in terms of surface morphology, from dense flower-like aggregated shape having low roughness (∼41 nm) to uniform porous structure with increased surface roughness (∼104 nm), was observed after plasma etching. Raman spectra revealed there was no obvious change in the bonding characteristics between the pristine and nanostructured N-NCD films. At surface RF gradient of 72.1 MV/m, maximum current density of 80.2 mA/cm 2 was reached for the nanostructured N-NCD cathode, increasing about 41% compared to that of the pristine N-NCD cathode. Furthermore, the mechanism in the enhanced RF field emission was tentatively discussed through the measured Fowler–Nordheim (F–N) features.