• Korean Journal of Food Science and Technology
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• 제31권3호
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• pp.746-750
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• 1999

The effects of electron-beam irradiation on the microbial and sensory qualities of pork loins were studied. The pork loins were aerobically packed in polyethylene films and exposed to absorbed doses of electron-beam at 0, 0.5, 1 and 2 kGy in ambient temperature. All samples were stored at $4{\pm}1^{\circ}C$. As an irradiation dose increased, decontaminating effects increased in terms of total microbial count, lactic acid bacteria and psychrotrophs during storage. All difference degrees in the triangle test were very low levels. In the descriptive analysis, Low dose irradiation did not affect aroma, off-flavor and acceptability in fresh and cooked meats.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2010년도 춘계학술회의 초록집
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• pp.21-21
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• 2010

(Ba,Sr)$TiO_3$ (BST) thin film with a perovskite structure has potential for the practical application in various functional devices such as nonvolatile-memory components, capacitor, gate insulator of thin-film transistors, and electro-optic devices for display. Normally, the BST thin films derived from sol-gel and sputtering are amorphous or partially crystalline when processed below $600^{\circ}C$. For the purpose of integrating BST thin film directly into a Si-based read-out integrated circuit (ROIC), it is necessary to process the BST film below $400^{\circ}C$. The microstructural and electrical properties of low-temperature crystallized BST film were studied. The BST thin films have been fabricated at $350^{\circ}C$ by UV-assisted rapidly thermal annealing (RTA). The BST films are in a single perovskite phase and have well-defined electrical properties such as high dielectric constant, low dielectric loss, low leakage current density, and high breakdown voltage. Photoexcitation of the organics contained in the sol-gel-derived films by high-intensity UV irradiation facilitates elimination of the organics and formation of the single-crystalline phase films at low temperatures. The amorphous BST thin film was transformed to a highly (h00)-oriented perovskite structure by high oxygen pressure processing (HOPP) at as low as $350^{\circ}C$. The dielectric properties of BST film were comparable to (or even better than) those of the conventionally processed BST films prepared by sputtering or post-annealing at temperature above $600^{\circ}C$. When external pressure was applied to the well-known contractive BST system during annealing, the nucleation energy barrier was reduced; correspondingly, the crystallization temperature decreased. The UV-assisted RTA and HOPP, as compatible with existing MOS technology, let the BST films be integrated into radio-frequency circuit and mixed-signal integrated circuit below the critical temperature of $400^{\circ}C$.

• Current Research on Agriculture and Life Sciences
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• 제30권1호
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• pp.51-59
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• 2012

Fresh oyster mushrooms (Pleurotus ostreatus) were gamma-irradiated at 0, 1, 2, and 3 kGy. The effects on various quality attributes were determined during storage at $5{\pm}1^{\circ}C$. Color changes were more prominent in the cap region than the stem part. At the start of storage increase of Hunter's L-value (lightness) was observed in the caps of 2 and 3 kGy-irradiated samples. The L-value was higher in the all irradiated samples during storage. The trend was different in the case of stem region, where L-value decreased upon irradiation, but remained high throughout storage. The ${\alpha}$-value declined, whereas the b-value increased following irradiation. Irradiation showed a dose-dependent effect on the firmness, which was clearer during storage, but the samples irradiated at 1 kGy maintained an overall better texture than other irradiated samples. The weight loss was also higher in the all irradiated samples during storage. The samples irradiated at 1 kGy showed good physical appearance without any fungal attack at the end of storage; however color change in cap region was quite apparent. The ultra-structural drastic effect of irradiation was understandable using scanning electron microscopy. E-nose analysis demonstrated a clear change in the volatile profiles of all irradiated samples. Although the effect of irradiation on quality characteristics was quite clear but the all irradiated samples were free from fungal attack that was observed in the case of control sample.

• Journal of the Korean Society of Food Science and Nutrition
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• 제45권2호
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• pp.247-254
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• 2016

This study evaluated the effects of low-dose X-ray irradiation treatment on quality characteristics and sensory evaluation of imported navel oranges during storage at $3^{\circ}C$ for 45 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, and changes in their color value, hardness, Brix/acid ratio, total sugar content, reducing sugar content, vitamin C contents, and sensory evaluation were investigated. There was no significant increase or decrease in Brix/acid ratio, total sugar content, reducing sugar content, or vitamin C content between the non-irradiated and irradiated samples. Color value of orange peels decreased with increasing levels of irradiation treatment. Color b value of orange pulp increased with an increase in irradiation dose. Difference in hardness between the non-irradiated and irradiated samples decreased at the end of storage. For the sensory evaluation after 30 days, sweetness and overall acceptability of irradiated samples at more than 0.6 kGy were low. These results suggest that X-ray irradiation under 0.6 kGy does not affect quality characteristics and sensory evaluation.

• Journal of the Korean Society of Food Science and Nutrition
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• 제44권1호
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• pp.128-136
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• 2015

This study investigated the effects of low-dose electron beam irradiation treatment on physicochemical and sensorial properties of imported navel oranges during storage at $3^{\circ}C$ for 45 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, and changes in their color values, hardness, Brix/acid ratio, total sugar contents, reducing sugar contents, vitamin C contents, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color values, Brix/acid ratio, total sugar contents, total reducing sugar contents, and vitamin C contents. Hardness of irradiated sample at 1 kGy decreased significantly in the early storage period, but the difference between non-irradiated and irradiated samples decreased again at the end of storage. For the sensory evaluation, scores of color, sweetness, flavor, and overall acceptability decreased as irradiation dose and storage period increased. Samples irradiated at over 0.8 kGy showed low preference in all scores except color. These results suggest that electron beam irradiation below 0.6 kGy does not affect physicochemical and sensory properties; thus, electron beam irradiation up to 0.6 kGy in imported navel oranges is optimum for minimizing quality changes and disinfestation treatment simultaneously.

• Biomedical Science Letters
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• 제6권2호
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• pp.119-129
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• 2000

The skin is an organ that has many important roles, including protection against infection, regulation of temperature and fluid loss, and sensory function. Injury to the skin, wound repair normally involves: (1) balanced activity of inflammation, (2) the re-epithelial phase and (3) the matrix formation of remodeling phase. Thus, skin wound healing is a finely controlled biological process involving a series of complex cellular interactions. Laser therapy is being implemented with increasing frequency in medicine. Low intensity laser is one that is capable of producing an energy density so low that any biologic alterations are the result of direct irradiation effect, not thermal events. This study was designed to evaluate the efficacy of low intensity laser therapy on skin wound healing in rabbits. A total of 10 male rabbits (New Zealand White Rabbit), age 8 weeks were used. Skin wound were surgically created dorso-lateral on the flank of 10 rabbits (2$\times$2 cm/damage areas). The experimental animals were treated with 5Hz (830 nm wave length) low-intensity laser (MILTA-01 Model) daily for 10 min (1.6 J/$cm^2$) for 12 days. Control animals were sham treated with the laser head. Laser irradiation animals showed a complete remodeling of the epithelial layer, a positive repair of connective tissues, and enhanced the wound closure rate over time as compared to the control animals. Especially, laser irradiation groups improved fibroblast activity, cellular content, granulation tissue formation, and collagen deposition which is resulted in improving the tensile strength of the wound. These findings suggest that laser photostimulation could accelerate healing of open wound in rabbits, and may be benefit in the treatment of open wound, including decubitis ulcers.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.312.1-312.1
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• 2016

We have deposited ZnO thin films by ultraviolet (UV) enhanced atomic layer deposition using diethylznic (DEZ) and water (H2O) as precursors with UV light. The atomic layer deposition relies on alternating dose of the precursor on the surface and subsequent chemisorption of the precursors with self-limiting growth mechanism. Though ALD is useful to deposition conformal and precise thin film, the surface reactions of the atomic layer deposition are not completed at low temperature in many cases. In this experiment, we focused on the effects of UV radiation during the ALD process on the properties of the inorganic thin films. The surface reactions were found to be complementary enough to yield uniform inorganic thin films and fully react between DEZ and H2O at the low temperature by using UV irradiation. The UV light was effective to obtain conductive ZnO film. And the stability of TFT with UV-enhanced ZnO was improved than ZnO by thermal ALD method. High conductive UV-enhanced ZnO film have the potential to applicability of the transparent electrode.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제12권1호
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• pp.1-10
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• 1999

In this paper, we have investigated the effects of the environmental factors on Low Molecular Weight (LMW) silicone fluid contents existing in high temperature vulcanized (HTV) silicone rubber sample, using dipping method and contact angle, current measurement. Artificial treatments such as immersion in water, elevated temperature, UV irradiation and dry band arcing under salt-fog condition are selected as the environmental factors. This results will be helpful to investigate the degradation with time and to expect a life time, because the LMW silicone content, which is important to recovery the hydrophobicity of silicone rubber surface, show different results by each environmental factors.

• Journal of the Korean Society of Safety
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• 제27권2호
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• pp.13-19
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• 2012

The effectiveness of treeing resistance in low density polyethylene containing azocompounds were investigated under radiation environments. 4-(4-nitrophenylazo)-1-naphthol and 4-(4-nitrophenylazo) resorcinol were selected for treeing inhibitors. LDPE containing the additives were crosslinked with dicumyl peroxide, irradiated by $Co^{60}$ ${\gamma}$-ray in the presence of air at room temperature. Treeing inception voltage, AC breakdown strength measurements were carried out for electrical insulation characteristics, thermoluminescence and gel contents were analyzed as various irradiation doses also. LDPE with treeing inhibitors showed much better insulation characteristics than pure LDPE. It is interpreted that molecular structures, polar groups and the type of radicals connected on the benzene ring of the additives affected electrical characteristics. From the results, 4-(4-nitrophenylazo) resorcinol was the most effective upon the best treeing and radiation resistance.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 한국염색가공학회 2012년도 제46차 학술발표회
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• pp.26-26
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• 2012

The hydrophobic nature of the wool surface give rise to difficult penetration of dye molecules. Among all the methods of modification, graft polymerization is an attractive method to impart a variety of functional groups to a polymer. Grafting has been made by irradiating the light on the polymer in the presence of a solvent containing monomer. The energy source commonly used are high-energy electrons, X-rays, UV and visible light. UV irradiation is a relatively low-energy radiation in comparison with others since it has the least possibility to change bulk properties. In the present paper, a photo-reactive dye was synthesized from quinizarin by the reaction with methacryloyl chloride. The synthesized dye was continuously grafted onto wool fabric at room temperature by UV irradiation. Several key parameters including UV energy, dye concentration and pH have been examined to understand their influence on the photoreactive coloration.