Recent Development of EPR Dosimetry

Gancheva, V.

doi:10.1007/978-1-4757-5166-6_14

Cited by 7 publications

(4 citation statements)

References 120 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a nondestructive quantitative method, the concept of EPR/alanine dosimetry attracted interest, an interest that gained considerable momentum in the mid-1980s through the careful investigations by Hansen and Olsen, and by Regulla, Deffner, and Wieser. − The longevity of the induced radicals suggested additional benefits such as cumulative radiation measurement procedures and long-term dosimeter storage for quality control and metastudies. Further corroboration was obtained from a number of subsequent very detailed studies by others using many different radiation qualities and environmental conditions. − Today, alanine is the most used material for solid-state EPR dosimetry purposes. Extensive international dosimetry services based on EPR/alanine dosimetry are now offered by, e.g., NIST (USA), PBL (Germany), and NPL (UK). − …”

Section: Introductionmentioning

confidence: 79%

In Quest of the Alanine R3 Radical: Multivariate EPR Spectral Analyses of X-Irradiated Alanine in the Solid State

et al. 2017

View full text Add to dashboard Cite

The amino acid l-α-alanine is the most commonly used material for solid-state electron paramagnetic resonance (EPR) dosimetry, due to the formation of highly stable radicals upon irradiation, with yields proportional to the radiation dose. Two major alanine radical components designated R1 and R2 have previously been uniquely characterized from EPR and electron-nuclear double resonance (ENDOR) studies as well as from quantum chemical calculations. There is also convincing experimental evidence of a third minor radical component R3, and a tentative radical structure has been suggested, even though no well-defined spectral signature has been observed experimentally. In the present study, temperature dependent EPR spectra of X-ray irradiated polycrystalline alanine were analyzed using five multivariate methods in further attempts to understand the composite nature of the alanine dosimeter EPR spectrum. Principal component analysis (PCA), maximum likelihood common factor analysis (MLCFA), independent component analysis (ICA), self-modeling mixture analysis (SMA), and multivariate curve resolution (MCR) were used to extract pure radical spectra and their fractional contributions from the experimental EPR spectra. All methods yielded spectral estimates resembling the established R1 spectrum. Furthermore, SMA and MCR consistently predicted both the established R2 spectrum and the shape of the R3 spectrum. The predicted shape of the R3 spectrum corresponded well with the proposed tentative spectrum derived from spectrum simulations. Thus, results from two independent multivariate data analysis techniques strongly support the previous evidence that three radicals are indeed present in irradiated alanine samples.

show abstract

Section: Introductionmentioning

confidence: 79%

In Quest of the Alanine R3 Radical: Multivariate EPR Spectral Analyses of X-Irradiated Alanine in the Solid State

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In many cases the defects last for very long times, which is the basis for archeological dating of teeth and quartz grains [175–177], dosimetry [178], and accident dosimetry [179]. Defects in irradiated crystalline alanine can be used to monitor radiation doses with high accuracy [180].…”

Section: Applications That Drive Innovationmentioning

confidence: 99%

The world as viewed by and with unpaired electrons

Eaton,

Eaton

2012

Journal of Magnetic Resonance

View full text Add to dashboard Cite

Recent advances in electron paramagnetic resonance (EPR) include capabilities for applications to areas as diverse as archeology, beer shelf life, biological structure, dosimetry, in vivo imaging, molecular magnets, and quantum computing. Enabling technologies include multifrequency continuous wave, pulsed, and rapid scan EPR. Interpretation is enhanced by increasingly powerful computational models.

show abstract

“…Upon dissolution of the solid materials, all free radicals recombine or interact with other species present in the solution. These effects are used for dosimetric purposes in the solid state/EPR dosimetry (for review, see Yordanov and Gancheva, 2003) or electronic spectroscopy (ES) with several dosimetric systems approved in the latter case up to now (Standards, 2002). In the recent decade sugar is shown as a very promising material for dosimetric purposes using ES with the method of lyoluminescence (Americo et al, 1995;Azorin et al, 1989;Gutierrez and Azorin, 1993) recording the light emitted upon recombination of sugar-free radicals during their dissolution.…”

Section: Introductionmentioning

confidence: 99%