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The ginger sample has been exposed to X-rays at cumulative doses. The foodstuffs irradiation is used in particular to improve their hygienic qualities and increase their shelf lives. This process has been approved by various international organizations: FAO -- AIEA -- WHO. In the present work, we propose to reproduce by simulation, based on a quantum approach, of the ESR (Electron Spin Resonance) spectra. The semi-classical approach is valid for a simple system, but not for a complex system such as an atom with hyperfine structure. In this case a quantum approach, based on spin Hamiltonian, is essential to interpret the ESR spectra. The main result is that the simulated spectra are in good agreement with the experimental ones obtained before and after irradiation. [ABSTRACT FROM AUTHOR]

Fast Transform Fourier (FFT) is used to generate the EPR (electron paramagnetic resonance) spectra. For the simulated radical EPR spectrum data, the imaginary component of the data is zero, and the real value represents the strength of the radical EPR signal. The algorithm is simplified if N is chosen to be a power of 2, where N is the number of data points. Among advantages of this method is that complicated spectra can be simulated very quickly and with very little computer memory by performing convolutions in frequency space. We applied the FFT to simulate the EPR spectra of the [O = N·(SO3)2]2- radical anion and the CNC·HCOOH radical. Only the real parts of the Fourier transforms of the lineshape functions are taken into account and both Gaussian and Lorentzian lineshapes are supported. [ABSTRACT FROM AUTHOR]

The detection and investigation of free radicals forming in living systems became possible due to the introduction of the method of spin traps. In this work, the electron spin resonance (ESR) spectra of DM PO=HO: and MGD-Fe-NO adducts are reproduced by simulation, based on the Fast Fourier Transform (FFT). The calculated spectral parameters as the hyperfine coupling constants, agree reasonably with the experimental data and the results are discussed. [ABSTRACT FROM AUTHOR]