• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.142-146
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• 2000

To observe the stimulating effects of low dose ${\gamma}-radiation$ on the seed germination, early growth and physiological activity in the gourd, seeds of three cultivars (Partner, Support, FR Yongja) were irradiated at the dose of $0.5{\sim}30\;Gy$. The hormetic effects of the low dose ${\gamma}-radiation$ on the growth were different from each cultivar. Low dose ${\gamma}-radiation$ had promoting effects on the germination at the optimum dose of 2 Gy and 8 Gy and on the early growth at the optimum dose of 4 Gy, 16 Gy and 20 Gy in Partner and Support cultivar and 1 Gy in FR Yongja cultivar. Irradiation didn't have significant effects on the chlorophyll contents of gourd plantlet. The antioxidant enzyme activity of gourd plantlet and early growth increased in low dose irradiation group.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.277-284
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• 1975

A result of measurement for the relative dose distribution of neutron gamma mixed radiation field in the biological irradiation facility installed at TRIGA Mark-III reactor is described. The relative dose distributions of neutron-gamma mixed radiation field in the biological exposure room have been experimentally determined using a thermoluminescent dosimeter. Presented herein in graphical forms are the experimental results obtained. It as observed that the region commonly having the characteristics of rather homogeneous horizontal and lateral dose distributions is confined to the area bounded by the two planes horizontally parallel to the beam direction with heights of about 40 cm and 130 cm, respectively, at distances beyond 100 cm from the segmentary surface of the aluminum pool liner projected into the the exposure room, while other areas show a steeper gradient in dosage, especially the places adjacent to the segment of the aluminum pool liner and near the inner po${\gamma}$lion of the concrete walls of the exposure room.

• Progress in Medical Physics
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• v.3 no.2
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• pp.23-31
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• 1992

The thermally stimulated luminecence (Thermoluminescence:TL) of manufactured beta-eucryptite was studied for dose range of 200cGy-20000Gy. The TL spectrum from cesium irradiated beta-eucryptite was measured over the temperature range of 300K to 600K. The linearity of TL intensity vs irradiation dose is valid up to 50Gy and beyond higher dose supralinearity and saturation come out. At the dose of 2000Gy, the net number of supralinearity is maximum. The net amount of supralinearity form newly formed trapping center by photon irradiation and totally calculated TL intensity are accord with the experimental results except for the 50Gy range that supralinearity appears.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.796-801
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• 2010

This study was carried out to establish a system for mutation breeding by irradiation of gamma-ray in $Rosa$ $hybrida$ Hort. The rooted cuttings of two roses, 'Spidella' and 'Cabernet' were irradiated with different gamma-ray doses (0, 30, 50, 70, 90, 110, 130, 150 and 170 Gy) from a $^{60}Co$ source to reveal an optimal dose for induction of mutants. The irradiated plants were planted in a greenhouse, and investigated on the appearance of petal color mutants and shoot growth by gamma ray dose. The 50% lethal doses ($LD_{50}$) of plant were 110 Gy for 'Spidella' and 150 Gy for 'Cabernet', respectively. The 50% decrease dose of shoot length was observed at 70-90 Gy dose for 'Spidella', and 110 Gy dose for 'Cabernet'. Solid, chimeric and mosaic petal mutants with various colors were induced from pink petal of 'Spidella' and red petal of 'Cabernet' when 30-170 Gy dose was irradiated. The mutants obtained from 'Spidella' had white, ivory, pinky ivory, light pink and deep pink petal colors. The mutants obtained from 'Cabernet' had pink, deep pink, purple red (magenta), orange red and purple petal colors. It was suitable to irradiate 70-90 Gy dose for 'Spidella' and 90-110 Gy dose for 'Cabernet' for the induction of various mutants considering plant survival rate, shoot growth and mutant occurrence rate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1047-1052
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• 1998

The effects of antioxidants such as ascorbyl palmitate(AP), tocopherol( Toc), BHA and ascorbyl palmitate＋ tocopherol(AP＋ Toc) on lipid peroxide formations in lard have been investigated during storage at 50oC after gamma irradiation with the dose of 1~10kGy. Immediately gamma irradiation greatly increased the initiative oxidation of lard as expected. But antioxidants were found to be greatly effective in minimizing the radiation induced peroxidation of lard. The decreasing order of effects on their antioxidative activities was AP>AP＋ Toc>BHA> Toc. Oxidation of lard during storage at 50oC after irradiation induced the acceleration of autooxidation. But the additions of an tioxidants inhibited the formation of peroxides. Their antioxidative activities during storage were BHA> AP＋ Toc> Toc>AP. Especially AP＋ Toc mixture was not significantly different from BHA (p>0.05).

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.198-201
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• 2008

The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of yellow poplar with doses of 0$\sim$450 kGy. The higher irradiation dose resulted in the more degradation of hardwood biomass not only from carbohydrates but also from lignin. This changes originated from the irradiation resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The more improvement on enzymatic hydrolysis by the irradiation was found in the xylan than in the cellulose of yellow poplar.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.487-492
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• 1998

The experiment was conducted to determine the effects of enhanced UV-B on growth and differential responses among cultivars in soybean. The soybean cultivars subjected to enhanced UV-B irradiation at daily dose of 11.32 kJ $m^{-2}(UV-B_{BE})$ revealed that the growth was significantly depressed. Plant height, leaf number, leaf area and dry weight were inhibited by UV-B irradiation showing differential responses among cultivars used. Danyeubkong seems to be less sensitive to the enhanced W-B irradiation, while Keunolkong more sensitive. Reduction of chlorophyll content was also found significantly greater to Keunolkong. Specific leaf weight an index of leaf thickness, and flavonoid content known as UV-absorbing compounds were significantly Increased in Danyeubkong by UV-B, but those In the other cultivars were not significantly affected. The results indicated that there are cultivar diferences in tile growth and phisiological responses to the enhanced UV-B irradiation and specific leaf weight and UV-absorbing compounds in the leaves were highly related to the sensitivity of soybean by UV-B irradiation.

• Korean Journal of Human Ecology
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• v.13 no.6
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• pp.1031-1036
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• 2004

Effects of irradiation on physico-chemical properties of beef and pork loins were examined. Beef and pork were irradiated at dose levels of 0, 0.5, 1, 2, 3, and 5 kGy with a use of Co-60 source. The drip loss of beef increased from 0 kGy to 5 kGy, whereas that of pork remained unchanged. TBA values of beef and pork increased due to irradiation. Irradiation caused a decrease in the lightness, redness, and yellowness of beef, whereas it did an increase in the same properties of pork. Irradiation also contributed to an increase in the solubility of salt soluble protein.

• KSBB Journal
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• v.26 no.6
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• pp.565-568
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• 2011

In this study, it was investigated the antioxidant activity of laminarin degraded by gamma irradiation. Because the activities of antioxidants have been attributed to various mechanisms, different assay methods have been conducted and compared. 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power, and lipid peroxidation inhibitory activity of degraded laminarin were measured and compared with non-degraded. All of these results showed that the antioxidant activity of laminarin degraded by irradiation was increased depending on the absorbed dose. Therefore, gamma irradiation could be an alternative method for the preparation of degraded laminarin with higher antioxidant activity.

• Carbon letters
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• v.16 no.2
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• pp.121-126
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• 2015

Carbon fibers are prepared by stabilizing pitch fibers accompanying electron beam (E-beam) irradiation. The carbon fibers pretreated by E-beam irradiation achieve a higher stabilization index than the carbon fibers that are only heat-stabilized. In addition, the carbon fibers subjected to E-beam irradiation in the stabilization step exhibit a comparable tensile strength to that of general purpose carbon fibers. The carbon fibers pretreated with an absorbed dose of 3000 kGy have a tensile strength of 0.54 GPa for a similar fiber diameter. Elemental, Fourier-transform infrared spectroscopy, and thermogravimetric analyses indicate that E-beam irradiation is an efficient oxidation and dehydrogenation treatment for pitch fibers by showing that the intensity of the aliphatic C-H stretching and aromatic $CH_2$ bending (out-of-plane) bands significantly decrease and carbonyl and carboxylic groups form.