Atmospheric dispersion and dose assessment of 137Cs and 131I from hypothetical incidents of nuclear power plant in Southeast Asia

In the event of radiological incidents, specifically nuclear accidents, a substantial quantity of radionuclides may be distributed, resulting in potential cancer hazards and the possibility of death. Hence, it is imperative for governing bodies to replicate hypothetical accidents that may occur from potential nuclear reactors, with the aim of ascertaining the probable dose exposure that the populace may face. The aim of this study was to evaluate the level of dispersion of 131I and 137Cs that would ensue from a hypothetical incident scenario of a nuclear power plant (NPP) in Ninh Thuan, Vietnam, and Mersing, Malaysia, by utilizing the HYSPLIT model. The model was set up based on the meteorological conditions in the potential site for NPP located in Southeast Asia. Following the study, a comparison was made between the results and the authorized dose limits proposed by the International Atomic Energy Agency to assess the potential mortality risk arising from an accident. The outcomes revealed that the mean activity concentration for both radionuclides was greater in Mersing than in Ninh Thuan on the initial day of the accident. The activity concentration of 137Cs and 131I at Mersing is the highest at 3.34 × 102 kBq/m3 and 2.01 × 104 kBq/m3, respectively. Meanwhile, Ninh Thuan has the highest activity concentration of 137Cs and 131I at 2.37 × 102 kBq/m3 and 1.43 × 104 kBq/m3, respectively. Based on these figures, the release of 137Cs and 131I at Mersing results in an effective dose of approximately 2.58 × 1

Solvothermal synthesized N–S doped carbon dots derived from cavendish banana peel (Musa paradisiaca) for detection of Fe(III) and Pb(II)

The synthesis of NS-CDs was carried out using precursors from Cavendish Banana Peel and l-Cysteine as a dopant with the solvothermal method. The characteristics of NS-CDs were analyzed through High-resolution transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), energy dispersive X-Ray spectroscopy (EDX), X-Ray Fluorescence spectrometer (XRF), X-Ray photoelectron spectroscopy (XPS), UV–Visible spectrophotometer, Photoluminescence, and Atomic Absorption Spectroscopy (AAS). Based on HR-TEM analysis, NS-CDs exhibited a spherical shape (dot) with an average particle size of 2.03 nm. Meanwhile, based on XRD characterization, NS-CDs showed a graphite carbon shape according to the diffraction patterns (002) and (001). Subsequently, XRF and EDX testing revealed that the elemental composition was dominated by carbon (C), nitrogen (N), Sulphur (S), and oxygen (O). Furthermore, in XPS testing, S2p, C1s, N1s, and O1s peaks correlated around 64 eV, 285 eV, 400 eV, and 531 eV respectively. In UV–Vis testing, the energy gap was found to be 5.71 eV (NS-CDs 3:1), 5.46 eV (NS-CDs 3:1), 5.25 eV (NS-CDs 1:1), 5.51 eV (NS-CDs 1:2), and 5.56 eV (NS-CDs 1:3). Characterization of PL for NS-CDs 3:1, 2:1, 1:1, 1:2, 1:3 showed peak excitation at 403 nm and emission at 493.39 nm, 493.65 nm, 494.98 nm, 496.04 nm, and 497.11 nm, respectively. During heavy metal ion detection testing, Fe(III) and Pb(II) using AAS instruments, it was found that the NS-CDs 1:3 sample yielded the best results with an Adsorption capacity worth 21.35 mg/L and Removal Efficiency worth 85.40 %. These results clearly indicate that NS-CDs material can be used as an ideal heavy metal detection material, especially in wastewater