• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.97-104
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• 2004

Neutron induced prompt gamma-ray spectroscopy(NIPS) system measures the prompt gamma-ray emitting by the interaction of a neutron with various materials. This system will be of great benefit to scientists worldwide, since it provides the non-destructive measurement of many element in either solid or liquid wastes. In this study, the full-energy-peak (FEP) efficiency calibration for a HPGe detector was constructed in the ${\gamma}$-ray energy range from 80 keV to 8 MeV, using $^{l33}$Ba and >TEX>$^{152}Eu$ RI sources and $ ^{35}Cl(n, ${\gamma}$)^{36}Cl$ thermal neutron captured reaction. The FEP efficiency curve for the higher energies using the $^{35}Cl(n, ${\gamma}$)^{36}Cl$ reaction was normalized with the curve obtained from the RI sources, since the accurate activity of its prompt ${\gamma}$-ray is unknown. The average thermal neutron flux was theoretically calculated using the FEP efficiency curve for the KCl standard solutions. The NIPS system equipped with a ${\gamma}$-${\gamma}$ coincidence setup with two n-type coaxial HPGe detectors was considered in order to reduce the interfering ${\gamma}$-ray background. The FEP efficiency curve for the ${\gamma}$-${\gamma}$ coincidence system was also obtained for full energy range. The performance of the normal and coincidence NIPS system was tested by comparing signal-to-noise ratio in each mode using the reference sample.e.

• Nuclear Engineering and Technology
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• v.2 no.4
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• pp.229-239
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• 1970

Various thermoluminescent properties of Korean natural quartz for possible use in ${\gamma}$-ray dosimetry has been studied. If the heating is exactly linear, ${\gamma}$-irradiated radiation sensitive (type 1) $\alpha$-quartz can yield a glow curve of single peak, hence glow peak height could be taken as a ${\gamma}$-dose for its dosimetry. Quartz crystal dosimeter exhibited the linearity of thermoluminescent intensity in the range from about 2$\times$10$^{3}$R to 2$\times$10$^{6}$ R, and also had an advantage of low fading because of the high peak temperature (300$\pm$4$0^{\circ}C$). The pulverized quartz sample having the grain size of 0.3<ø<0.9mm showed the linearity of T. L. intensity in the range from 50R to 2$\times$10$^3$R. Therapeutic application of the pulverized sample on the correct measurement of the absorbed dose in a body region of a cancer patient seems to be successful.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1100-1102
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• 2015

In the study, stereo-based of gamma-ray sources detector for the space including the gamma-ray source to scan in a raster scan method, and obtains a visible light image and the gamma-ray image. We went to retrieve and visualize the distance to source and the direction of the 3-dimension information from Stereo gamma-ray detectors. Configuration of the detector consisted of gamma-ray detecting sensor for gamma-ray Sources, pan-tilt for the scanning of the raster for detecting sources, and CCD camera for visible-light image. Implement a stereo structure of the device to measure the spatial distribution of source, the gamma-ray Detector and CCD camera for the stereo image acquisition was as each configuration 2. The gamma-ray detector and a visible light camera to revision the distribution of detection source, After performing each of the cameras of the stereo correction and shows the distribution of the gamma-ray Sources through 중첩 visible light image and the gamma-ray image. After Rectification process of Left and right image, we were derived visualization results of the stereo image.

• Nuclear Engineering and Technology
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• v.5 no.4
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• pp.291-309
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• 1973

Exposure rates due to leakage gamma-rays from operating reactors TRIGA Mark II and III were measured in a horizontal plane by means of scintillation spectrometry using a 3"$\times$3" cylindrical Nal(T1) detector associated with a 400 channel pulse height analyzer under varied conditions of reactor operation. In determining exposure rate due to the leakage gamma-rays at each point of measurement, Moriuchi's spectrum-exposure rate conversion theory was applied instead of using conventional responce matrix method which necessitates very complicated procedures to convert a spectrum into exposure rate. The results show that a basic pattern of "typical" spectrum of the reactor leakage gamma-rays is neither affected by thermal output of the reactor, nor influenced by overall attenuation in radiation intensity. It was indicated that he attenuation of the leakage gamma-rays in air in terms of exposure rate as a whole follows an exponential law, and the total exposure rate due to the leakage gamma-rays at a certain point is nearly proportional to thermal output of the reactor. The complexity in spectrum measured for a movable core reactor, TRIGA Mark III, was analyzed through spectrum resolution, and proper judgement of the leakage gamma-rays in a complex spectrum was discussed.ctrum was discussed.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.953-960
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• 2022

The measurement of branching ratio of ¹⁶⁷Yb radioactive isotopes from gamma-ray spectrum of ¹⁶⁹Tm(p,3n)¹⁶⁷Yb reaction were performed by using a 100-MeV proton linear accelerator of the Korea Multi-purpose Accelerator Complex (KOMAC). The ¹⁶⁷Yb isotope has a half-life of 17.5 minutes and decays to ¹⁶⁹Tm. The gamma rays generated from the ¹⁶⁷Yb isotope were measured using an HPGe detector gamma ray spectroscopy system. The energy calibration of the detector and the efficiency measurement of the detector were determined using a standard source. The gamma rays of known main energy (62.9, 106.2, 113.3, 143.5 and 176.3 keV) were measured. On the other hand, information about the intensity of the generated gamma rays is very inaccurate. Therefore, in this study, the decay strength of the main gamma rays was accurately measured. Overall, it was different from the previously known results, and in particular, it was found that the intensity of the main decay gamma ray, such as the 113.3 and 106.2 keV gamma ray, was overestimated, and it was found that the gamma ray, such as 62.9, 116.7 and 143.5 keV was underestimated. The present results are considered to be important information in the fields of nuclear fusion, astrophysics and nuclear physics in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.139-144
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• 1969

1. In order to obtain useful mutants such as early maturity, resistance to lodging, high protein and oil content, and capability of high yield, dormant seeds of two soybean varieties, Jang Dan Baik Mok and Clark, were treated with ${\gamma}$-ray, Ethyl Methane Sulfonate(EMS), Ethylene Imine(EI)and combinations of ${\gamma}$-ray and EMS or EI. 2. The germination rate and survival rate in a variety Jang Dan Baik Mok were significantly decreased with ${\gamma}$-ray treatment while it was not the same in the Clark variety. A significant decrease for seedling height measured at 14 and 21 days after sowing was found with the increase of ${\gamma}$-ray dose in both varieties. 3. Germination rates in both varieties were significantly decreased as EI concentration increases, particularly severe damage in germination was observed at 0.008 Mo. concentration. Germination rate damages were found with EMS concentration increases in the variety Jang Dan Baik Mok while no regular responses in seedling height were observed in the variety Clark. 4. Germination rate was significantly lowered with the combined treatment of EMS and ${\gamma}$-ray 24KR than that of EMS alone. In the treatments of ${\gamma}$-ray with three levels of EI concentration, the combined treatments except 24KR+EI 0.002 Mol. resulted in better germination than of EI alone. In both varieties, significant reduction in seedling height was observed in the combined treatments of ${\gamma}$-ray with various concentrations of EMS, whereas stimulation effect on seedling height was found with treatment of ${\gamma}$-ray EI +0.08Mol. 5. Germination rate, survival rate, and plant height as criteria of radio sensitivity, variety Jang Dan Baik Mok is moze sensitive to ${\gamma}$-ray, EMS, and EI than the variety Clark, and the varietal difference in responsibility to mutagen may be due to the genetic-constitution of the varieties.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.58-61
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• 2000

This study was conducted to determine the effect of low dose ${\gamma}-ray$ on the germination rate and physiology of germinative seeds of welsh onion ( Allicm fistulosum L. cv. Sukchangwoidae ) and spinach ( Spinacia oleracea L. cv. Chungrok ). The germination rate of irradiation group was much higher than that of the control. Especially it was noticeably higher in 1 or 2 Gy irradiation groups in the sowing spinach seeds on paper towel. On the welsh onion, the germination rate of the 1 Gy irradiation group increased by 17% compared to that of the control. Ion leakage from seeds irradiated with low dose of ${\gamma}-ray$ was decreased compared to that from the control especially at the early stage of incubation when examined by means of electric conductance. This tendency was confirmed in seeds of welsh onion and spinach. Starch hydrolysis was stimulated by ${\gamma}-ray$ irradiation in welsh onion. Furthermore ${\gamma}-ray$ irradiation was beneficial to keeping the vitality of seeds as determined through decarboxylation of glutamic acid.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1005-1010
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• 1999

To study the shortening of rigor mortis and changes in the morphological properties of gamma-irradiated pre-rigor bovine muscle (M). Sternomandibularis during post mortem, this experiment was performed with a test of shear force and the observation of the ultrastucture of raw muscle. The time elapsed until maximum shear force values was shortened by gamma irradiation, depending upon the dose. The release of rigor mortis started earlier than control (non-irradiated muscle). A shortening of the length of the Z-line and the maintenance of the sarcomere length by gamma irradiation was observed. The breakdown of the perimysium of muscle bundles was observed more in irradiated samples than in the control. In conclusion, it is considered that gamma irradiation on pre-rigor beef shortens aging-period, improves tenderness and enhances the beef quality.

• Food Science and Preservation
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• v.8 no.1
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• pp.9-15
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• 2001

The effects of water soaking and gamma irradiation on the storage quality of chestnuts (Castanea crenata) were investigated. Chestnuts weirs soaked in water for 48 hrs at room temperature, irradiated at 0, 0.15, 0.25 and 0.35 kGy of $\^$60/Co gamma ray, and then stored at 0$\^{C}$ and 95$\pm$2% RH for 9 months. Spouting was observed at the end of storage only in chestnuts that were soaked and irradiated at below 0.25 kGy. Rotting was found from the early stage of storage in all pre-treatment conditions, but the rotting rate of soaked chestnuts was higher twice than unsoaked ones after 9 months of storage. Weight loss was lower in soaked than unseated samples regardless of irradiation dose. Loss of flesh firmness was appreciably retarded as irradiation dose increased. Total sugar content decreased slowly in irradiated samples at the later periods of storage. Gamma irradiation resulted in the decrease of vitamin C content immediately after treatment, but retarded its loss rate during storage. Soluble tannin content was not affected by gamma irradiation at scout inhibition doses.

• Journal of radiological science and technology
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• v.22 no.1
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• pp.67-71
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• 1999

Effect of single intraperitoneal administration of Cordyceps sinensis (Cs) extract at 24 hour before whole-body ${\gamma}$ - irradiation on the survival ratio, body weight, organ weight changes and serum metabolites in the irradiated mice were investigated. The single pre-administration of Cs extract increased the 40-day survival ratio of irradiated mice from 66.7% to 83.4%. The administration of Cs extract completely prevented weight reductions of spleen and thymus produced by ${\gamma}$ - irradiation (P<0.05, P<0.01). Similar but somewhat less radioprotective effect was also found in the testis of the Cs treated mice. The administration of Cs inhibited the serum hyperglycemia produced by irradiation on the day 7th(P<0.01). However, it did not influence the serum cholesterol and protein levels on the days examined. The present study is the first report regarding Cs which was tested and found to be radioprotective.