Oxadiazole‐fused combinations are of great concern for the novelty of effective therapeutic agents. In this context, a series of oxadiazole included pyranopyrazoles were prepared under eco‐friendly synthetic way by using montmorillonite k10 as a catalyst. All the final outcomes were formed with good yields. Further, compounds screened for their antioxidant assay. Most of the compounds revealed promising activity. Among all outcomes, electron rich‐substituted compounds at para position demonstrated higher antioxidant activity than their corresponding ortho‐substituted compounds. All belongings concluded that this eco‐friendly path is preferable to prepare therapeutic compounds. Further, biotic results established that all these biologically active compounds fit for supplementary to develop exogenous antioxidant drugs.

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The natural radionuclide (238U, 226Ra, 232Th and 40K) concentrations in 152 soil samples were determined from two major granite areas in Guangzhou, using high resolution γ-ray spectroscopic system based on the characteristic spectral peaks. The mean activity values for 238U, 226Ra, 232Th and 40K were found to be 156.6±98.8, 160.9±96.5, 184.8±101.5 and 832.5±493.1 Bq kg–1 dry mass, respectively. The absorbed dose rate (D) calculated from activity concentration of 226Ra, 232Th and 40K ranged from 53.2 to 497.1 nGy h–1 with a mean of 220.7 nGy h–1. The Radium equivalent activity (Raeq), the outdoor annual effective dose and the external hazard index (Ir), which resulted from the natural radionuclides in soil, were also calculated and found to vary from 119.7 to 1117.2 Bq kg–1, from 0.07 to 0.61 mSv and from 0.33 to 3.07, respectively. The radium equivalent activities and the external hazard index in all the soil samples were same as 64.5% higher than the limit of 370 Bq kg–1 and 1.0, respectively. The outdoor annual effective dose was higher than the worldwide mean value of 0.07 mSv.

Zero-valent iron nanoparticles( nano-Fe0) were applied as a treatment tactics for a uranium-containing mine wastewater taken from Shaoguan, Guangdong, China. Different factors including pH value, nano-Fe0 dosage,reaction time were introduced to study the effect posed by those factors.Results indicated that those factors have significant effect on uranium removal rate.The best removal effect happened when pH=5~6, nano-Fe0 iron dosage is 2g/l,reaction time is 1h.It is also demonstrated that nano-Fe0may be an effective material for treatment of complex uranium-contaminated effluent.