Radiation-induced lattice relaxation in [Formula: see text]-Fe[Formula: see text]O[Formula: see text] nanorods

We report radiation-induced lattice relaxation of the [Formula: see text]-Fe[Formula: see text]O[Formula: see text] and its associated alteration of particle morphology. The [Formula: see text]-Fe[Formula: see text]O[Formula: see text] was grown in solution by microwave hydrothermal synthesis technique in which more than half of the synthesized material was nanorods with axis along the (001) direction. Five sets of the synthesized [Formula: see text]-Fe[Formula: see text]O[Formula: see text] samples were irradiated using gamma-ray from [Formula: see text]Co cell with doses of 600 kGy, 700 kGy, 800 kGy, 900 kGy, and 1 MGy. The investigation of the pristine and gamma-irradiated samples was carried out using X-ray powder diffraction, transmission electron microscope, and electron paramagnetic resonance methods. Results showed that continuous alternation of radiation-induced lattice compression and expansion causes lattice relaxation. The morphology of the [Formula: see text]-Fe[Formula: see text]O[Formula: see text] nanorods was found to change with absorbed dose into buckyball-shaped particles in response to the alternation of the compression and expansion strain. The EPR results showed a correlation between distortion in the [Formula: see text]-[Formula: see text] octahedron structure and the relaxation of the lattice. The synthesis, growth, and relaxation are discussed in detail.

Isotope signature and elemental characteristics of subsurface formations around deep-laying coal seams probed by means of atomic and nuclear-based techniques

A systematic investigation on the isotopic and elemental signature, for both stable and radioactive elements, and mineral contents was performed to examine the characteristics of subsurface formations collected at different depths between 3.962 km and 4.115 km around deep-laying coal seams located under the Marmarica plateau in Egypt. Concentrations of major and minor oxides (Na₂O, MgO, Al₂O₃, SiO₂, SO₃, K₂O, CaO, TiO₂, MnO, ΣFeO + Fe₂O₃, SrO, ZrO₂, and BaO) were determined by X-ray fluorescence and dependencies among these concentrations revealed the type and sort of the formations. Organic contents were determined by Fourier Transform infrared spectroscopy to investigate the variation of the CO/CC bonding ratio with depth. Rare earth elements (REE), specifically Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu were determined by inductively coupled plasma mass spectrometry while actinoids were detected by the radioactive decay of its daughter nuclei. The results showed a high trapping of REE elements and actinoids in layers above the coal seams which indicates the occurrence of aqueous flow followed by possible sorption in these layers. The mobility of the fluid was investigated using the process radioactive decay series between Ra226 and Ac228 from one side and their daughters from the other side.

The influence of gamma radiation on organic compounds having carbon ring and its application in dosimetry

The formation of highly oxidizing radicals in multifunctional-solid compounds upon irradiation with gamma-ray had been investigated. Five organic compounds having a single carbon ring had been used in the present investigation; these materials are 1-chloro-4-nitrobenzene, 4′-aminoacetophenone, 3′-hydroxyacetophenone, n-anthranilic acid, and triphenylmethane. These material were irradiated using 60Co radiation with different doses between 20 and 100 kGy. Electron spin resonance spectroscopy spotted increases of the resonance absorption having landé factor around 2.0113 ± 0.003 upon irradiation with the increasing of dose. This resonance absorption was related to the formation of long-lived oxygen radicals that were attached to one of the radiation synthesized compounds. The method of infrared absorption spectroscopy emphasized the formation of cyclic and aliphatic hexane in addition to the active oxygen radicals. n-Anthranilic acid was found to be suitable for radiation the dosimetry with long-lasting radiation signature as electron spin and also to determine the exposure dose. The time-lapse infrared and electron spin resonance measurements had been used to tracked the formation of active species within the time-lapsed after the end of exposure; results showed that the dosimetric signature may be used as a tracker for the time when the exposure happens.