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31.
LIU Yan-Ping CHEN Zhao-Yang BA Wei-Zhen FAN Yan-Wei DU Yan-Zhao PAN Shi-Lie GUO Qi 《中国物理C(英文版)》2008,32(5)
The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity.Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-acoess and hazardous.In addition.optical fiber dosimeters are immune to electrical and radio-frequency interference.In this paper,a novel remote optical fiber radiation dosimeter is described.The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL.The measuring range of the dosimeter is from 0.1 to 100 Gy.The equipment is relatively simple and small in size,and has low power consumption.This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions. 相似文献
32.
K. Oda Y. Imasaka T. Yamauchi Y. Nakane A. Endo H. Tawara Y. Yamaguchi 《Radiation measurements》2005,40(2-6):570-574
Subsequent to the proposal of a two-layer structured radiator for more efficient detection of high-energy neutrons with a plastic nuclear track detector (PNTD), its availability has been investigated both experimentally and theoretically. An inner deuterized hydrocarbon (CD2) layer adjacent to PNTD should play the role of both a radiator of deuterons recoiled there and a degrader for energetic protons recoiled in the outer layer of a CH2 material. It was found that the energy dependence of the efficiency was changed sensitively by the thickness of the CD2 layer. A best combination of CH2 and CD2 thickness was estimated under a condition of a constant total thickness. For example, the sensitivity could be flattened within 20% between about 5 and 70 MeV by using -CD2 and -CH2. 相似文献
33.
A neutron personal dosemeter using CR-39 as a detector and hydrogenated materials as proton converters for fast neutron detection plus an air layer for thermal neutron detection is being developed in our laboratory. To increase the CR-39 response to thermal neutrons, the air converter was substituted with Nylon in some dosemeters. Several dosemeters with these two configurations were mounted on a water-filled phantom and exposed under different incidence angles (0, 30 and 60) to: (i) Three ISO neutron sources (241Am–Be, bare 252Cf and moderated 252Cf with Cd shielding), and (ii) two realistic neutron sources (SIGMA and moderated 252Cf) at the IRSN (Cadarache) facilities. The irradiated detectors were electrochemically etched and evaluated in order to determine their dose equivalent response in terms of Hp(10,α). The results obtained are compared to those obtained from Monte Carlo simulations using the MCNPX code. 相似文献
34.
M. M. Asimov R. M. Asimov A. N. Rubinov S. A. Mamilov Yu. S. Plaksii 《Journal of Applied Spectroscopy》2006,73(4):583-587
We propose a method for dosimetry of the biological response to laser irradiation based on determination of the amount of
oxygen additionally supplied to the tissue. We show that it is feasible to determine the therapeutic dose from the change
in the degree of oxygen saturation of the blood, heart rate, hemoglobin concentration in the blood, and exposure time.
__________
13Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 516–520, July–August, 2006. 相似文献
35.
A new radiochromic thin film dosimeter has been developed for use in radiation processing. The dosimeter's properties are similar to those of the commercially available FWT-60-00 Radiochromic Detectors with three key differences: 1) a lower sensitivity allows reading the optical density at the peak of the absorbtion spectrum (ca. 600 nm) for absorbed doses to over 50 kGy, 2) a radiation-insensitive dye additive allows for automatic thickness correction, and 3) another additive extends to higher doses the agreement between gamma and E-beam calibrations. The dosimeter is analyzed for its sensitivity, temperature and humidity dependencies, stability, reproducibility, and agreement of gamma and E-beam calibrations. 相似文献
36.
The gamma-induced ESR in CR-39 plastic has been studied and the possibility of using it as a gamma-ray dosimeter was investigated. The induced ESR was found to vary linearly with the dose up to 700 krad. The fading of the induced ESR signal at room temperature has been also investigated. The results suggest the possible use of CR-39 plastic for gamma dosimetry in the range 0 … 700 krad. Es wurde die γ-induzierte ESR-Technik am CR-39 Plast untersucht und ihre Eignung als Gammastrahlen-Dosimeter geprüft. Die induzierte ESR variierte linear bis zu einer Dosis von 700 krad. Das Fading des induzierten ESR-Signals bei Zimmertemperatur wurde ebenfalls untersucht. Die Ergebnisse zeigten, daβ cine Verwendung des CR-39 Plast als Dosimeter für Gammastrahlen im Bereich von 0 … 700 krad möglich ist. 相似文献
37.
J. Fellinger T. Hahn J. Henniger K. Hübner P. Schmidt 《Isotopes in environmental and health studies》2013,49(7):342-346
TL materials have a small intrinsic sensitivity for fast neutrons. In order to increase this sensitivity one uses hydrogen containing radiators giving recoil protons as a result of the neutron interaction. By combining the proton radiator technique with the use of TL detectors having various glow peaks with a different response to recoil protons an additional sensitivity yield can be reached. The paper deals with the calculation procedure for the (radiator) sensitivity component. For the LiF phosphors TLD-600 and TLD-700 calculated and experimentally determined fast neutron sensitivities are presented for the glow peaks V and VII. The results show that for accident dosimetry a sufficient agreement of the dedector response with the dose-to-fluence conversion factors is obtained. 相似文献
38.
Abstract Results of the quantum-chemical simulation of the formation of structural and radiation defects are reviewed, using ice, silicon, and silicon dioxide as examples. The relationship between the structural elements of these crystals and the structural defects is analysed. Models of the main defects, their optical characteristics, and the activation energy of their migration are discussed. The relationship between the characteristics obtained by quantum-chemical calculations and the parameters of the macroscopic kinetics of the processes induced by defects in dielectric crystals is considered. 相似文献
39.
In the present work, characteristic features of the radiolytical intermediates produced in gamma-irradiated solid sulfamethazine (SMH) were investigated by electron spin resonance (ESR) spectroscopy. The heights of the resonance peaks, measured with respect to the spectrum baseline, were used to monitor microwave saturation, temperature and time-dependent kinetic features of the radical species contributing to the formation of recorded experimental ESR spectra. Three species having different spectroscopic and kinetic features were observed to be produced in gamma-irradiated SMH. SO2, which is the most sensitive group of radiation in the SMH molecule, was found to be at the origin of radiation-produced ionic radical species. Based on the experimental results derived from the present study, the applicability of ESR spectroscopy to radiosterilization of SMH was discussed. In the dose range of interest (0.5–10 kGy), the radiation yield of solid SMH was calculated to be very low (G=0.45) compared with those obtained for sulfonamide aqueous solutions (G=3.5–5.1). Based on these findings, it was concluded that SMH and SMH-containing drugs could be safely sterilized by gamma radiation and that ESR spectroscopy could be successfully used as a potential technique for monitoring their radiosterilization. 相似文献
40.
P. M. Bhujbal 《辐射效应与固体损伤》2013,168(6):428-435
The lyoluminescence (LL), thermoluminescence and mechanoluminescence (ML) of a γ -ray-irradiated powder of NaCl:Dy (0.05–0.5 mol%) phosphor are reported in this paper. The nature of intensity variation of the respective luminescence spectra with different γ -ray doses and with different concentrations of Dy3+ doped in NaCl are found to be similar. The LL and ML intensities differed from each other, but their nature is found to be similar in a sublinear form up to a high dose (5.0 kGy) of γ -rays. Thus, the prepared phosphor may be useful for accidental radiation dosimetry up to a high dose (5.0 kGy) of γ -rays using the LL and ML techniques. 相似文献