Gamma-ray irradiation and post-irradiation responses of high dose range RADFETs

2005 ◽  
Author(s):  
A. Jaksic ◽  
G. Ristic ◽  
M. Pejovic ◽  
A. Mohammadzadeh ◽  
C. Sudre ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Dose Range ◽  
High Dose ◽  
Post Irradiation ◽  
Gamma Ray Irradiation

Gamma-ray irradiation and post-irradiation responses of high dose range RADFETs

2002 ◽  
Vol 49 (3) ◽  
pp. 1356-1363 ◽  
Author(s):  
A. Jaksic ◽  
G. Ristic ◽  
M. Pejovic ◽  
A. Mohammadzadeh ◽  
C. Sudre ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Dose Range ◽  
High Dose ◽  
Post Irradiation ◽  
Gamma Ray Irradiation

Gamma-Ray Radiation-Induced Surface Hydrophobic Effects in Invar Alloy

2012 ◽  
Vol 482-484 ◽  
pp. 1585-1591 ◽  
Author(s):  
Cheng Fu Yang ◽  
Wei Wen Wang ◽  
Hsin Hwa Chen ◽  
Wei Tan Sun ◽  
Chi Lin Shiau ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Structural Changes ◽  
Gamma Ray ◽  
Small Deviation ◽  
Contact Angles ◽  
Invar Alloy ◽  
Hydrophobic Effects ◽  
Post Irradiation ◽  
Radiation Induced ◽  
Gamma Ray Irradiation

In this paper, we report a new phenomenon observed in the gamma-ray radiation-induced hydrophobic effects on an Invar surface: When the Invar alloy is subjected to different doses of gamma-ray irradiation, the contact angle increases with the radiation dose. Invar samples with exposed to a higher dose appear more hydrophobic, but this tendency disappears following post-irradiation etching. The contact angles of the irradiated and etched Invar samples can be restored back to a stable value with small deviation after 30 min of annealing at 150°C. X-ray diffraction (XRD) analysis found no crystalline structural changes. High resolution field emission scanning microscope (FE-SEM) analyses showed that irradiation might induce crack-like surfaces which could be removed at higher radiation dose in the following acid etchings. It is believed that the chemical bonds of Invar oxide on the surface were broken by the gamma-ray irradiation, thus raising the likelihood of binding with free ions in the air and resulting in the exclusion of the hydrophilic OH bonds, leaving a hydrophobic post-irradiation Invar surface.

Effect of γ-ray irradiation on performance of LiNbO(3)-based piezoelectric vibration sensors

2021 ◽  
Author(s):  
Huifen Wei ◽  
Wenping Geng ◽  
Kaixi Bi ◽  
Tao Li ◽  
Xiangmeng Li ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Extreme Environments ◽  
Theoretical Work ◽  
High Dose ◽  
Mems Devices ◽  
Micro Electro Mechanical Systems ◽  
Vibration Sensors ◽  
Irradiation Dosage ◽  
Gamma Ray Irradiation ◽  
Γ Ray

Abstract LiNbO3 (LN)-based micro-electro-mechanical systems (MEMS) vibration sensors exhibit giant prospection in extreme environments, where exist a great amount of irradiation. However, to the best of our knowledge, it is still unknown whether the irradiation affects the performance of LN-based piezoelectric MEMS sensors. Based on this consideration, it is necessary to model the irradiation environment to investigate the effect of high dosage irradiation on LN-based vibration sensors. Firstly, the theoretical work is done to study the Compton Effect on the Gamma-ray irradiation with Co-60 source. After irradiation, X-ray diffraction (XRD) characterization was performed to verify the effect of irradiation on the crystalline of LN thin film. Meanwhile, the performances of output voltages on the five MEMS devices under various dosage of irradiation are compared. As a result, a neglected shift of 0.02 degrees was observed from the XRD image only under maximum irradiation dosage of 100 Mrad(Si). Moreover, the output voltages of cantilever-beam vibration sensors decrease by 3.1%. Therefore, it is verified that the γ-ray irradiation has very little influence on the LN-based MEMS vibration sensors, which have great attraction on the materials and sensors under high-dose irradiation.

Dosimetric evaluation of methyl red radiochromic film for radiation processing

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Awad AL Zahrany ◽  
Khalid Rabaeh ◽  
Molham Eyadeh ◽  
Ahmed Basfar
Keyword(s):  
Gamma Ray ◽  
Dose Range ◽  
Absorbed Dose ◽  
Radiochromic Film ◽  
High Dose ◽  
Methyl Red ◽  
Radiation Processing ◽  
Content Type ◽  
The Stability ◽  
The Impact

Purpose The purpose of this paper is to present a radiochromic film dosimeter containing polyvinyl alcohol (PVA) matrix and various concentrations of methyl red (MR) dye for high dose measurements. Design/methodology/approach The MR-PVA films were exposed to irradiation up to 60 kGy using 60Co source of gamma ray. The ultraviolet and visible regions (UV/VIS) spectrophotometry were used to examine the optical density of pre-and post-irradiated dosimeters at 424 nm. Findings The dose sensitivity of MR-PVA films increases significantly with increasing MR dye concentrations in the dose range of 5 to 60 kGy. The impact of relative humidity, irradiation temperature, dose rate and the stability of the films has been analyzed. The overall uncertainty of the MR-PVA film dosimeter is 6.12% (Double Standard-deviation, 95% confidence level). Practical implications It was found that the MR-PVA films may be used as high dose dosimeter with an acceptable overall uncertainty in routine industrial radiation processing. Originality/value The color bleaching of irradiated MR-PVA films in terms of specific absorbance curves increases significantly with increasing absorbed dose up to 60 kGy.

Effects of Irradiation on Chitosan-Coated Nanoparticles for Hyperthermia

2011 ◽  
Vol 311-313 ◽  
pp. 419-431
Author(s):  
Kwo Ping Chang ◽  
Zhi Yuan Lin ◽  
Mao Chin Hung ◽  
Bor Tsung Hsieh
Keyword(s):  
Specific Absorption Rate ◽  
Gamma Ray ◽  
Quality Characteristic ◽  
Molar Ratio ◽  
High Dose ◽  
Optimal Parameters ◽  
Control Factors ◽  
Coated Nanoparticles ◽  
Gamma Ray Irradiation ◽  
Positive Effect

The optimal parameters of the chitosan-coated ferrofluid under two patterns of irradiation were investigated in this study. The quality characteristics were set both to the SAR (specific absorption rate, W/g) and the particle size (nm). The control factors were chosen as the gamma irradiation dose (Gy), the quantities of chitosan (g), and the molar ratio of Fe3+to Fe2+. It shows that SAR is a better choice for determining the quality characteristic. The quantities of chitosan have a less significant impact on SAR. The optimal condition for the Fe3+/Fe2+ratio was found to be between 2.0 to 2.5 when synthesizing the magnetite Fe3O4cores. High dose (100 k Gy in this study) of gamma ray irradiation given only to the solid chitosan will have a significantly positive effect on SAR of the chitosan-coated ferrofluid for hyperthermia. However, high dose irradiation of the chitosan-coated ferrofluid tends to destroy the chitosan-magnetite cores bonds.

scholarly journals Gamma-ray irradiation and post-irradiation at room and elevated temperature response of pMOS dosimeters with thick gate oxides

2011 ◽  
Vol 26 (3) ◽  
pp. 261-265 ◽  
Author(s):  
Momcilo Pejovic ◽  
Svetlana Pejovic ◽  
Edin Dolicanin ◽  
Djordje Lazarevic
Keyword(s):  
Elevated Temperature ◽  
Threshold Voltage ◽  
Gamma Ray ◽  
Temperature Response ◽  
Oxide Thickness ◽  
Threshold Voltage Shift ◽  
Voltage Shift ◽  
Post Irradiation ◽  
Gamma Ray Irradiation ◽  
Oxide Traps

Gamma-ray irradiation and post-irradiation response at room and elevated temperature have been studied for radiation sensitive pMOS transistors with gate oxide thickness of 100 and 400 nm, respectively. Their response was followed based on the changes in the threshold voltage shift which was estimated on the basis of transfer characteristics in saturation. The presence of radiation-induced fixed oxide traps and switching traps - which lead to a change in the threshold voltage - was estimated from the sub-threshold I-V curves, using the midgap technique. It was shown that fixed oxide traps have a dominant influence on the change in the threshold voltage shift during gamma-ray irradiation and annealing.

Grafting of polymers from clay nanoparticles via high-dose gamma-ray irradiation

2007 ◽  
Vol 61 (17) ◽  
pp. 3723-3727 ◽  
Author(s):  
Tao Wang ◽  
Mozhen Wang ◽  
Zhicheng Zhang ◽  
Xuewu Ge ◽  
Yue'e Fang
Keyword(s):  
Gamma Ray ◽  
High Dose ◽  
Clay Nanoparticles ◽  
Gamma Ray Irradiation

scholarly journals A Performance Evaluation of a Notebook PC under a High Dose-Rate Gamma Ray Irradiation Test

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Jai Wan Cho ◽  
Kyung Min Jeong
Keyword(s):  
Performance Evaluation ◽  
Dose Rate ◽  
Nuclear Power ◽  
Gamma Ray ◽  
Control Unit ◽  
High Dose Rate ◽  
High Dose ◽  
Robot System ◽  
Irradiation Test ◽  
Gamma Ray Irradiation

We describe the performance of a notebook PC under a high dose-rate gamma ray irradiation test. A notebook PC, which is small and light weight, is generally used as the control unit of a robot system and loaded onto the robot body. Using TEPCO’s CAMS (containment atmospheric monitoring system) data, the gamma ray dose rate before and after a hydrogen explosion in reactor units 1–3 of the Fukushima nuclear power plant was more than 150 Gy/h. To use a notebook PC as the control unit of a robot system entering a reactor building to mitigate the severe accident situation of a nuclear power plant, the performance of the notebook PC under such intense gamma-irradiation fields should be evaluated. Under a similar dose-rate (150 Gy/h) gamma ray environment, the performances of different notebook PCs were evaluated. In addition, a simple method for a performance evaluation of a notebook PC under a high dose-rate gamma ray irradiation test is proposed. Three notebook PCs were tested to verify the method proposed in this paper.

scholarly journals Sensitivity of P-Channel MOSFET to X- and Gamma-Ray Irradiation

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Milić Pejović ◽  
Olivera Ciraj-Bjelac ◽  
Milojko Kovačević ◽  
Zoran Rajović ◽  
Gvozden Ilić
Keyword(s):  
Threshold Voltage ◽  
Gamma Ray ◽  
Dose Range ◽  
Absorbed Dose ◽  
Tube Voltage ◽  
Threshold Voltage Shift ◽  
X Ray ◽  
Practical Applications ◽  
Most Significant Change ◽  
Gamma Ray Irradiation

Investigation of Al-gate p-channel MOSFETs sensitivity following irradiation using 200 and 280 kV X-ray beams as well as gamma-ray irradiation of 60Co in the dose range from 1 to 5 Gy was performed in this paper. The response followed on the basis of threshold voltage shift and was studied as a function of absorbed dose. It was shown that the most significant change in threshold voltage was in the case of MOSFET irradiation in X-ray fields of 200 kV and when the gate voltage was +5 V. For practical applications in dosimetry, the sensitivity of the investigated MOSFETs was also satisfactory for X-ray tube voltage of 280 kV and for gamma rays. Possible processes in gate oxide caused by radiation and its impact on the response of MOSFETs were also analyzed in this paper.

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