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Amphetamine-type stimulants are among the most prevalent and widespread commonly abused drugs. Amphetamine and its derivatives were detected in aquatic environment. This study aimed to demonstrate experimentally the ability of γ-irradiation combined with persulfate anions (S 2 O 8 2– ) to degrade and mineralize the amphetamine in aqueous solution. An initial amphetamine concentration of 125 µM in distilled water was completely degraded by a γ-ray dose of 2.8 kGy. Generation of the sulfate radical (SO 4 •– ) from the fast reaction of added S 2 O 8 2– with hydrated electrons ( e aq − ; k eaq − / S2 O8 2– = 1.1×10 10 M −1 s −1 ) improved the efficiency of amphetamine degradation and mineralization. A γ-ray dose of 0.667 and 0.350 kGy in the absence and presence of S 2 O 8 2– anions degraded 90% of the amphetamine, respectively. For γ-ray/free O 2 and γ-ray/S 2 O 8 2– systems, 11.5 and 7 kGy was required for 50% amphetamine mineralization, respectively. Addition of HCO 3 – anions lowered the amphetamine degradation yield, whereas N 2 gas, SO 4 2– , and Cl – anions had a negligible effect. [ABSTRACT FROM AUTHOR]

Aromatic sulfonated compounds and naphthalene derivatives are major chemical compounds used in the industry. Electron beam irradiation of aqueous solutions of 2-naphthalenesulfonate (90 µM) was investigated under various experimental conditions. The results obtained demonstrate that the 2-NS concentration decreased dramatically on increasing the absorbed dose in the range 0–1000 Gy. The effectiveness of the radiolytic system was demonstrably enhanced by the addition of oxidants (S 2 O 8 2− or H 2 O 2 ). 2-NS removal was higher with S 2 O 8 2− than with H 2 O 2 . For the EB, EB/H 2 O 2 , and EB/S 2 O 8 2− systems, the absorbed doses for 90% elimination of 2-NS (D 90 ) were 700, 480, and 274 Gy, respectively. 2-NS is poorly mineralized by EB but more than 35% mineralization was reached for 15 kGy when oxidants (820 µM S 2 O 8 2− or 935 µM H 2 O 2 ) were added. In all systems, the mineralization yield was markedly higher when air (i.e. dissolved oxygen increase) was introduced between successive doses. For 50% 2-NS removal, seven sulfonated transformation products were identified using LC/MS analyses. For the highest absorbed doses the sulfonate group in 2-NS was converted to sulfate ions in the radiolytic systems. [ABSTRACT FROM AUTHOR]

Desulfurization of light distillation fractions including gasoline, kerosene and diesel obtained from the four Arabian crude oils (heavy, medium, light and extra light) upon γ-rays irradiation to different doses was investigated. In addition, yields vol%, FTIR analysis, kinematic viscosity and density of all distillation fractions of irradiated crude oils were evaluated. Limited radiation-induced desulfurization of those fractions was observed up to an irradiation dose of 200 kGy. FTIR analysis of those fractions indicates the absence of oxidized sulfur compounds, represented by S=O of sulfone group, indicating that γ-irradiation of the Arabian crude oils at normal conditions does not induce an oxidative desulfurization in those distillation fractions. Radiation-induced sulfur transfer decreases by 28.56% and increases in total sulfur by 16.8% in Arabian extra light oil and Arabian medium crude oil respectively. [ABSTRACT FROM AUTHOR]

This study reports the impact of γ-ray exposure on the nanostructural, morphological, and optical characteristics of lead iodide (PbI 2) thin films (TFs). These PbI 2 were deposited on glass substrates using a spin coating technique. The γ-ray irradiation was carried out using Co-60 gamma source with dose range from 0 to 100 kGy. The X-ray diffraction (XRD) results revealed a decrease in crystallinity and an increase in crystallite size of PbI 2 as a function of γ-ray dose. Field emission scanning electron microscopy (FESEM) exhibited the variations in surface morphology with increasing γ-ray dose. The elemental composition of as prepared TFs was confirmed by energy dispersive X-rays (EDX) analysis. The optical transmission of PbI 2 TFs was evaluated with varying the γ-ray doses. The estimated energy band gap (Eg) reduced from 2.54 to 2.45 eV with γ-ray dose. Photoluminescence (PL) spectra represent a broad peak centered at 507.64 nm with a hump present at 519.73 nm in the as prepared sample, which grow gradually with increasing the γ-ray dose. The maximum value of mobility was found to be 10.48 cm2 V−1 s−1 at 50 kGy. The change in the mobility is associated with the density of structural defects influenced by γ-ray doses. These effects conclude that γ-irradiation played a key role in structural, electrical and optical properties of the PbI 2 TFs and proposes that the γ-irradiation response makes it a good candidate for radiation detecting material application. • The spin coating technique was employed deposit the PbI 2 thin films. • Thin films were irradiated with γ-ray using 60Co source with different dose level (0, 25, 50, 75, 100 kGy). • X-ray diffraction revealed that the crystallite size increased in with γ-ray dose. • The energy band gap of PbI 2 thin films dropped after irradiated. • The electrical conductivity and carrier concentration were enhanced with γ-ray doses. [ABSTRACT FROM AUTHOR]