• Food Science of Animal Resources
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• v.36 no.2
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• pp.215-222
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• 2016

The combined effects of irradiation and aging temperature on the microbial and chemical quality of beef loin were investigated. The samples were vacuum-packaged, irradiated at 0 or 2 kGy using electron-beam (EB), and stored for 10 d at different aging temperatures (2, 14, or 25℃). The microbial growth, shear values, meat color, and nucleotide-related flavor compounds of the samples were analyzed. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and Escherhia coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose. Irradiation reduced the total aerobic bacteria (TAB) over the storage, but higher aging temperature increased the TBA. Thus TAB increased sharply in non-irradiated and high temperature-aged (14, 25℃) beef samples after 5 d. With increasing aging temperature and aging time, shear force values decreased. Lipid oxidation could be reduced by short aging time at low aging temperature. The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the aging period. As aging period and temperature increased, IMP decreased and hypoxanthine increased. Considering microbial and physicochemical properties, irradiation can be used for raw beef to be aged at relatively high temperature to shorten aging time and cost.

• Journal of the Korean institute of surface engineering
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• v.25 no.6
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• pp.299-308
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• 1992

Titanium nitride(TiN) has been synthesized by nitrogen ion irradiation onto the Ti thin film deposited on STD11 and SKH9 tool materials. The effect of irradiation flux and substrate temperature on the formation behavior and mechanical properaties of TiN were investigated through X-ray diffraction analysis, hardness and pin-on-disc wear testings. Nitrogen ion irradiation onto arc evaporated Ti thin film produced TiN of < 200> orientation at elevated temperature and thereby enhancing surface microhardness by 50% at maximum. Wear resistance was also improved by nitrogen irradiation at most process conditions. The enhancement of wear resistance appeared to be more effective for the nitrogen irradiated conditions at room temperature than at elevated temperature.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.84-89
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• 1972

An experiment was carried out to investigate the optimum doses of gamma-irradiation for sprouting inhibition of onion bulbs with irradiation time and storage conditions. The results. obtained are as follows: 1) The irradiation doses of 5, 7 and 10 krad, respectively, at 11, 32 and 66 days after harvest were sufficient to inhibit subsequent sprout of onion bulbs obtained from Nampyeong district. When they were irradiated at 96 day after harvest, however, there was little sprout-inhibition by 15 krad. In case of onion bulbs obtained from Changnyeong district, sprout was inhibited by doses of 8 and 12 krad respectively, at 51 and 89 days after harvest. 2) Low-temperature storage after irradiation was not effective in sprout-inhibition of onion bulbs. Onion bulbs stored at low temperature of $5^{\circ}C$ rather showed higher sprouting rate as compared with that of room temperature. 3) Rot increased in irradiated lot and at room temperature, and spores of Aspergillus sp. were little germinated at a level of 100 krad. 4) The respiratory rate of irradiated onion bulbs was higher immediately after irradiation but lower one week after irradiation than control. Respiratory quotient of tissues seems to be little affected by gamma-irradiation.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.174-176
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• 2009

This paper aims to investigate generation conditions necessary for the most efficient generation by measuring electricity power under various irradiation conditions, since the photovoltaic generation system has high costs and low efficiency. This thesis aims to investigate generation conditions necessary for the most efficient generation by measuring electricity power under various irradiation conditions, since the photovoltaic generation system has high costs and low efficiency. Although the generation power increased with the irradiation, the former did not vary directly as the latter. This meant that the variation of the generation power was concerned in the temperature of a module, the ambient temperature, and the directions of irradiation as well as the irradiation. As for the monthly accumulated irradiation and monthly accumulated power, the maximum irradiation and generation power were observed in May and October and the irradiation, the power and the accumulated generation power were all the highest in spring, followed by fall, summer and winter.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.610-613
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• 2020

Specimens of austenitic stainless steel were irradiated with 6 MeV Xe ions to two doses of 7 and 15 dpa at room temperature and 300 ℃ respectively. Then partial irradiated specimens were subsequently thermally annealed at 550 ℃. Irradiation-induced BCC-phase formation and magnetism were analyzed by grazing incidence X-ray diffraction (GIXRD) and vibrating sample magnetometer (VSM). It has been shown that irradiation damage level, irradiation temperature and annealing temperature have significant effect on BCC-phase formation. This BCC-phase changes the magnetic behavior of austenitic stainless steel. The stress relief and compositional changes in matrix are the driving forces for BCC-phase formation in austenitic stainless steel during ion irradiation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.2
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• pp.249-254
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• 2015

Solution-derived amorphous indium-gallium-zinc oxide (a-IGZO) thin-film-transistor (TFTs) were developed using a microwave irradiation treatment at low process temperature below $300^{\circ}C$. Compared to conventional furnace-annealing, the a-IGZO TFTs annealed by microwave irradiation exhibited better electrical characteristics in terms of field effect mobility, SS, and on/off current ratio, although the annealing temperature of microwave irradiation is much lower than that of furnace annealing. The microwave irradiated TFTs showed a smaller $V_{th}$ shift under the positive gate bias stress (PGBS) and negative gate bias stress (NGBS) tests owing to a lower ratio of oxygen vacancies, surface absorbed oxygen molecules, and reduced interface trapping in a-IGZO. Therefore, microwave irradiation is very promising to low-temperature process.

• 한국초전도학회:학술대회논문집
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• 2008.08a
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• pp.19-19
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• 2008

• Nuclear Engineering and Technology
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• v.52 no.6
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• pp.1243-1251
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• 2020

Irradiation-induced damage of binderless nanoporous-isotropic graphite (NPIG) prepared by isostatic pressing of mesophase carbon microspheres for molten salt reactor was investigated by 3.0 MeV He⁺ irradiation at room temperature and high temperature of 600 ℃, and IG-110 was used as the comparation. SEM, TEM, X-ray diffraction and Raman spectrum are used to characterize the irradiation effect and the influence of temperature on graphite radiation damage. After irradiation at room temperature, the surface morphology is rougher, the increase of defect clusters makes atom flour bend, the layer spacing increases, and the catalytic graphitization phenomenon of NPIG is observed. However, the density of defects in high temperature environment decreases and other changes are not obvious. Mechanical properties also change due to changes in defects. In addition, SEM and Raman spectra of the cross section show that cracks appear in the depth range of the maximum irradiation dose, and the defect density increases with the increase of irradiation dose.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.260-266
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• 2013

The study was carried out to determine the gel pasting properties of barley (Hordeum vulgare L. cv. Geoncheonheugbori) as affected by different proton beam irradiation. The ${\lambda}max$, blue value, and amylose content were significantly associated with increasing proton beam irradiation. The pasting time in barley flour irradiated with proton beam ranged 0.09 to 0.16 min shorter than nonirradiated barley flour. Gel pasting temperature ranged 57.4 to $60.5^{\circ}C$. Gel pasting temperature in barley flour decreased with increasing proton beam irradiation. Proton beam irradiation caused a significant decrease in the onset temperature (To), peak temperature (Tp), conclusion temperature (Tc) and enthalpy change (${\Delta}H$). Gelatinization range (R) in barley starch was more broaden than that of non-irradiated barley starch. Barley starches gave the strong diffraction peak at around $2{\Theta}$ values$15^{\circ}$, $18^{\circ}$, $20^{\circ}$, and $23^{\circ}$ $2{\Theta}$. Peak intensity tended to increase with increased proton beam irradiation. The granule crystallinity is closely associated with decreased amylose and increased amylopectin component. The crystallinity degree of barley starch irradiated with proton beam was significantly increased and it ranged from 24.9 to 32.9% compared to the non-irradiated barley starches. It might be deduced that proton beam irradiation causes significant changes of properties of starch viscosity in rice, especially at high irradiation of proton beam.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.429-433
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• 2012

Purpose: While rapeseed oil, soy bean oil, palm oil and waste cooking oil are being used for biodiesel, the viscosity of them should be lowered for fuel. The most widely used method of decreasing the viscosity of vegetable oil is to convert the vegetable oil into fatty acid methyl ester but is too expensive. This experiment uses ultrasonic energy, instead of converting the vegetable oil into fatty acid methyl ester, to lower the viscosity of the waste cooking oil. Methods: For irradiation treatment, the sample in a beaker was irradiated with ultrasonic energy and the viscosity and temperature were measured with a viscometer. For heating treatment, the sample in a beaker was heated and the viscosity and temperature were measured with a viscometer. Kinematic viscosity was calculated by dividing absolute viscosity with density. Results: The kinematic viscosity of waste cooking oil and cooking oil are up to ten times as high as that of light oil at room temperature. However, the difference of two types of oil decreased by four times as the temperature increased over $83^{\circ}C$. When the viscosity by the treatment of ultrasonic energy irradiation was compared to one by the heating treatment to the waste cooking oil, the viscosity by the treatment of ultrasonic energy irradiation was lower by maximum of 22% and minimum of 12%, than one by the heating treatment. Conclusions: Ultrasonic energy irradiation lowered the viscosity more than the heating treatment did, and ultrasonic energy irradiation has an enormous effect on fuel reforming.