Pymeprazole

This study evaluates the thermoluminescence (TL) dosimetry potential of Ce-doped lithium zinc borate (LZB) synthesized via the solid-state reaction method. The crystalline phase integrity and functional groups were verified using XRD and FTIR, while SEM-EDS confirmed the homogenous distribution of Ce-activators. Vibrating Sample Magnetometer (VSM) was used for magnetic characterisation, which demonstrated the emergence of superparamagnetic behaviour after doping. Samples were subjected to 6 MeV electron and 6 MV X-ray irradiation (0.5-8 Gy) to evaluate dose-response linearity using clinical LINAC. Results indicate that LZB:Ce (1 %) significantly enhances dose-response linearity and sensitivity compared to the undoped host. Kinetic analysis was performed using Chen's peak-shape method, where a calculated geometric factor (0.50) confirmed general-order kinetics and significant charge carrier re-trapping. The extracted activation energies E_a ranged at ∼0.72/0.92 eV for shallow trap and ∼4.99/5.22 eV for deep trap due to defect centre, calculated by Computerized Glow Curve Deconvolution (CGCD). Despite a relative reduction in peak intensity, the material exhibited superior thermal stability and improved fading over 50 days, positioning Ce-doped LZB as a robust and technically viable candidate for dosimetry application and need long term study for more feasibility as an alternative.

Laizhou Bay (LZB) is heavily polluted by perfluoroalkyl substances (PFAS), especially perfluorooctanoic acid (PFOA), from the nearby industrial emission. PFOA has been subjected to strict control, leading to the increasing use of PFOA substitutes. However, the present pollution status of PFOA substitutes in the LZB area is unclear. In this study, 14 legacy and 18 emerging perfluoroalkyl substances (PFAS) in surface water and sediment samples from LZB area were investigated. Two homologues of hexafluoropropylene oxide trimer acid (HFPO-TrA (C7 and C8)) were first identified in LZB area. The results revealed that emerging PFAS have overtaken legacy PFAS as the major PFAS contaminants in seawater. Legacy PFAS constituted only ∼13-47 % of the total PFAS concentration (∑PFAS) in the seawater and ∼ 37-68 % of the ∑PFAS in the sediment. PFOA was found to be the major legacy PFAS in both seawater and sediment. Among the emerging PFAS, two series of perfluoropolyether carboxylic acid (PFECA) homologues accounted for 86-97 % of the total emerging PFAS in seawater and 57-96 % of the total emerging PFAS in sediment. The major source of PFAS was point source from the Xiaoqing River for the inner bay area, whereas the outer bay area may receive external input from the Bohai Sea. Although environmental risks were low for legacy PFAS, HFPO homologues as a whole may present high risks in a large area by an optimistic evaluation method. This highlights the urgent research needed for emerging PFAS - especially those PFOA substitutes - in the LZB area.