| Autor: |
Alizadeh, Elahe, Sanche, Léon |
| Předmět: |
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| Zdroj: |
Radiation Protection Dosimetry; Sep2012, Vol. 151 Issue 3, p591-599, 9p |
| Abstrakt: |
The problem of absolute measurements of radiation damage in films of nanometer thicknesses is addressed. Thin films of DNA (∼2–160 nm) are deposited onto glass substrates and irradiated with varying doses of 1.5-keV X-rays under dry N2 at atmospheric pressure and room temperature. For each different thickness, the damage is assessed by measuring the loss of the supercoiled configuration as a function of incident photon fluence. From the exposure curves, the G-values are deduced, assuming that X-ray photons interacting with DNA deposit all of their energy in the film. The results show that the G-value (i.e. damage per unit of deposited energy) increases with film thickness and reaches a plateau at 30±5 nm. This thickness dependence provides a correction factor to estimate the actual G-value for films with thicknesses <30 nm thickness. Thus, the absolute values of the damage can be compared with that of films of any thickness under different experimental conditions. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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