2. Determination of Absorbed-Dose Rates

Potassium-40 was determined in soil in an area with 40,000 m² situated in the western State of Pernambuco, Brazil. For radiometric measurements, the gamma spectrometry method with a high purity germanium (HPGe) detector was used. Sampling of 78 soil samples has been performed at intervals of 25 m. The specific activities of 40K were calculated based on the photopeak of 1.46 MeV. Values from 541 to 3,572 Bq kg-1 were obtained (mean of 1,827 Bq kg-1). These values allowed the determination of the elemental concentrations as well as the absorbed dose rates in air, 1 m above the ground. The values varied from 1.7 to 11.5% (mean of 6%) and from 23.4 to 154.3 nGy h-1 (mean of 79 nGy h-1), respectively.

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Absorbed Dose Rates in Tissue from Prompt Gamma Emissions from Near-thermal Neutron Absorption

Health Physics ◽

10.1097/hp.0000000000000288 ◽

2015 ◽

Vol 109 (4) ◽

pp. 319-322

Author(s):

Scott O. Schwahn

Keyword(s):

Thermal Neutron ◽

Absorbed Dose ◽

Prompt Gamma ◽

Neutron Absorption ◽

Dose Rates ◽

Absorbed Dose Rates

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Influences of Absorbed Dose Rate on the Mechanical Properties and Fiber–Matrix Interaction of High-Density Polyethylene-Based Carbon Fiber Reinforced Thermoplastic Irradiated by Electron-Beam

Polymers ◽

10.3390/polym12123012 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3012

Author(s):

Se Kye Park ◽

Dong Yun Choi ◽

Duyoung Choi ◽

Dong Yun Lee ◽

Seung Hwa Yoo

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Carbon Fiber ◽

Dose Rate ◽

High Density Polyethylene ◽

Absorbed Dose ◽

High Density ◽

Absorbed Dose Rate ◽

Dose Rates ◽

Absorbed Dose Rates

In this study, a high-density polyethylene (HDPE)-based carbon fiber-reinforced thermoplastic (CFRTP) was irradiated by an electron-beam. To assess the absorbed dose rate influence on its mechanical properties, the beam energy and absorbed dose were fixed, while the absorbed dose rates were varied. The tensile strength (TS) and Young’s modulus (YM) were evaluated. The irradiated CFRTP TS increased at absorbed dose rates of up to 6.8 kGy/s and decreased at higher rates. YM showed no meaningful differences. For CFRTPs constituents, the carbon fiber (CF) TS gradually increased, while the HDPE TS decreased slightly as the absorbed dose rates increased. The OH intermolecular bond was strongly developed in irradiated CFRTP at low absorbed dose rates and gradually declined when increasing those rates. X-ray photoelectron spectroscopy analysis revealed that the oxygen content of irradiated CFRTPs decreased with increasing absorbed dose rate due to the shorter irradiation time at higher dose rates. In conclusion, from the TS viewpoint, opposite effects occurred when increasing the absorbed dose rate: a favorable increase in CF TS and adverse decline of attractive hydrogen bonding interactions between HDPE and CF for CFRTPs TS. Therefore, the irradiated CFRTP TS was maximized at an optimum absorbed dose rate of 6.8 kGy/s.

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Radiation-induced color centers in LiF for dosimetry at high absorbed dose rates

Nuclear Instruments and Methods ◽

10.1016/0029-554x(80)90237-2 ◽

1980 ◽

Vol 175 (1) ◽

pp. 17-18 ◽

Cited By ~ 27

Author(s):

William L. McLaughlin ◽

Arne Miller ◽

Stuart C. Ellis ◽

Arthur C. Lucas ◽

Barbara M. Kapsar

Keyword(s):

Absorbed Dose ◽

Color Centers ◽

Dose Rates ◽

Radiation Induced ◽

Absorbed Dose Rates

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Nanoparticles synthesis by electron beam radiolysis

Open Chemistry ◽

10.2478/s11532-014-0502-x ◽

2014 ◽

Vol 12 (7) ◽

pp. 774-781 ◽

Cited By ~ 5

Author(s):

Ioan Călinescu ◽

Diana Martin ◽

Daniel Ighigeanu ◽

Adina Gavrila ◽

Adrian Trifan ◽

...

Keyword(s):

Silver Nanoparticles ◽

Electron Beam ◽

Chemical Reduction ◽

Absorbed Dose ◽

Reduction Process ◽

High Dose Rate ◽

High Dose ◽

Experimental Conditions ◽

Dose Rates ◽

Absorbed Dose Rates

AbstractElectron beam (EB) irradiation is a useful method to generate stable silver nanoparticles without the interference of inherent impurities generated from chemical reactions. Our experiments were carried out using linear electron beam accelerators with two different EB absorbed dose rates: 2 kGy min−1 and 7–8 kGy s−1, and with different absorbed dose levels. The optimum conditions for silver nanoparticles (AgNPs) generation by radiolysis, or by radiolysis combined with chemical reduction, were established. In order to obtain a good yield for AgNPs synthesized by radiolysis, a high dose rate is required, resulting in a rapid production process. At low absorbed dose rates, the utilization of a stabilization agent is advisable. By modifying the experimental conditions, the ratio between the chemical and radiolytic reduction process can be adjusted, thus it is possible to obtain nanoparticles with tailored characteristics, depending on the desired application.

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