• Nuclear Engineering and Technology
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• 제51권8호
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• pp.1970-1977
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• 2019

Understanding the irradiation hardening effect of structural steels under various irradiation conditions plays an important role in developing advanced nuclear systems. Such being the case, a crystal plasticity model for body-centered cubic (BCC) crystal based on the density of dislocations and irradiation defects is summarized and numerically implemented in this paper. Based on this model, nano-indentation hardness of Chinese A508-3 steels with ion irradiation is calculated. Very good agreement is observed between simulation and experimental data of several different irradiation doses subjected to various operating temperatures, from which, it can be concluded that indentation hardness increases with increasing irradiation dose at both room temperature and high temperature. Consequently, the validity of this model has been proved properly, and furthermore, the model established in this paper could guide the study of irradiation hardening effect and temperature effect to some extent.

• 미생물학회지
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• 제6권2호
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• pp.54-62
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• 1968

The effect of gamma-ray on yeast cells Sacch. cerevisiae, and the leakage of cellular constituents such as carbohydrates, ribose, amino acids, inorganic phosphates and organic phosphates have been studied. The samples of yeast cells washed throughly and starved intensively, radiation effects were compared with those of control (un-starved), the irradiation dose rates are in the range from 24 Kr. up. to 480, Kr. The loss of 260m$\mu$. absorbing material, are also observed. Mechanisms of membrane damage by gamma-irradiation are discussed corelating to permeability changes and loss of substances, then active and passive transport process are also under considerations in discussion. The experimental results are as follows, 1. Carbohydrates of yeast cell leak out by gamma-irradiation, and amounts of loss increase proportionally as the increasing of radiation dose, curve of carbohydrates loss in starved cells is parallel with those of non-starved cells. 2. Ribose leak out less than that of carbohydrate from irradiated cell, the dose response curve of loss is straight and proportional to the increasing of radiation doses, slope of the curve is much lower than of carbohydrates. 3. Amino acids also leak out and the curve of losses to radiation is not proportional, it is revealed that there are little losses from yeast at lower doses of irradiation. 4. The losses of inorganic phosphates increase unproportionally to the increasing of irradiation doses, there are little leakage at the lower doses of irradiation. The losses of organic phosphates increase proportionally to the increasing of irradiation doses, and the amount of losses are much more than that of inorganic phosphate at lower doses of irradiation. 5. Leakage from irradiated yeast cells was shown to be due to passive transport process not an energy requiring process of ion transport. 6. Loss of 260 m$\mu$. absorbing material is little more than that of control yeast by the gamma-irradiation dose of 120K.r. and 240K.r.

• 한국식품영양과학회지
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• 제29권6호
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• pp.1035-1041
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• 2000

멸치 액젓의 새로운 위생화 방법으로 감마선 조사기술을 이용하였고, 산업적 생산에 응용하고자 기존의 가열살균 및 정밀여 과방법과 비교하여 미생물학적, 이화학적 및 관능적 품질변화를 조사하였다. 감마선을 조사한 멸치 액젓은 미생물 제어에 효과적 인 것으로 나타났으며 조사선량이 증가함에 따라 색이 밝아지는 등 외관적으로 긍정적인 효과를 보였다. 또한 저장 기간 중 pH, 염도 및 점도 등의 변화 없이 품질이 유지되었고, 색, 향, 맛 및 종합적 기호도 등 관능적 측면에서도 대조구와 가열살균 시험구에 비해 높은 선호도를 나타내어 정밀여과 시험구와 마찬가지로 우수한 품질을 나타내었다 감마선 조사구 중 5kGy의 선량을 적용할 때 미생물학적 및 관능적 품질이 가장 적합한 것으로 나타났다. 따라서 멸치액 젓 에 감마선을 조사함으로써 가열살균 및 정밀여과 방법과 비교할 때 품질의 변화 없이 우수한 멸치 액젓을 생산할 수 있었으며, 산업적 대규모 생산에 새로운 위생화 기술로서 이용할 수 있는 가능성을 제시하였다.

• Korean Journal of Acupuncture
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• 제24권3호
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• pp.91-103
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• 2007

Objectives : The purpose of this study was to investigate the usability of live blood analysis on interior and exterior vascular laser irradiation therapy. Methods : We had analyzed the changing forms of the live blood sample with microscope before and after vascular laser irradiation therapy of blood. The live blood analysis was operated on Rouleau of red cell, erythrocyte aggregation, thrombocyte aggregation, uric acid crystals, red crystals, protoplasts. First, we analyzed all patients on each item, then did same thing classified two groups, Interior and exterior. Results : Rouleau of red cell, erythrocyte aggregation, thrombocyte aggregation, uric acid crystals, red crystals, protoplasts were decreased significantly, after interior and exterior aggregation, uric acid crystals. Interior vascular laser irradiation therapy was more effective than interior on Rouleau of red cell, erythrocyte aggregation, thrombocyte aggregation, uric acid crystals. Interior vascular laser irradiation therapy was more effective than exterior on red crystals, protoplasts. Conclusions : This study suggests that live blood analysis has the usability on vascular laser irradiation therapy. Then according to interior and exterior vascular laser irradiation therapy, the result has some different on each item. So it is better that choose the method, interior or exterior, for more effective therapy.

• 열처리공학회지
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• 제17권3호
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• pp.151-164
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• 2004

The changes of microstructural and mechanical properties were evaluated for the high burn-up fuel claddings after the neutron irradiation of $1.8{\sim}3.1{\times}10^{20}n/cm^2$ (E>1.0 MEV) in HANARO research reactor. After the irradiation, the spot-type dislocations (a-type dislocations) were easily observed in most claddings, and the density of the dislocations was different depending on the grains and was higher at grain boundaries than within grains. As the final annealing temperature increased, the density of spot-type dislocations increased and the line-type dislocations (c-type dislocations) which was perpendicular to the <0002> direction, appeared sporadically in some claddings. However, the types of precipitates in the fuel claddings after the irradiation were not changed from that in unirradiated claddings. The mechanical properties including the hardness, strength and elongation after the irradiation were changed due to the formation of spot-type dislocations. That is, the increase in hardness and strength as well as the decrease in elongation after the irradiation was occurred simultaneously with increasing the final annealing temperature. Owing to the Nb contribution to the formation of spot-type dislocation during the irradiation, the increase in hardness and strength in higher Nb-contained Zr alloys after the irradiation was higher than that in lower Nb-contained Zr alloys.

• 한국생활과학회지
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• 제20권5호
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• pp.1009-1023
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• 2011

This study was carried out to investigate the variations of catechu dyed fabrics under UV irradiation. Catechu dyed cotton and silk fabrics mordanted with Fe and Cu were irradiated with UV under dry and wet conditions, and then were evaluated on color changes and mechanical properties. Owing to UV irradiation, the K/S values of catechu dyed cotton fabrics increased until a certain amount of time but those of catechu-dyed silk fabrics increased continuously. Cu mordanting cotton fabrics showed the smallest changes due to the UV treatment, and silk fabrics mordanted with Fe showed the largest changes. Wetted fabrics were accelerated maillard browning by UV. Un-mordanted cotton fabrics treated with UV under dry conditions changed its YR color to Y, but changed its Y color to YR under wet conditions. However, mordanted cotton fabrics treated with UV didn't change their color. Dyed silk fabrics except those Fe mordanted and in wet conditions continued to keep their color after UV irradiation. Silk fabric mordanted with Fe under wet conditions changed its Y color to YR by UV irradiation. UV irradiation didn't affect the mechanical properties of catechu-dyed cotton and silk fabrics in any significant way.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.240-240
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• 2009

We developed the low level laser therapy(LLLT) apparatus for external injury cure using a GaAsP Diode. This equipment was fabricated by using GaAsP diode and a microcontroller, and designed to enable us to control light irradiation timer, and frequency. In this paper, the designed device was used to find out how GaAsP diode light source affects the skin wound of RAT. In the experiment, $1cm^2$ wounds on the External injury of RAT were made. Light irradiation RAT and none light irradiation RAT divided, each RAT was irradiated 20 min a day for 9 days. In result, compared with none light irradiation RAT, the lower incidence of inflammation and faster recovery was shown in light irradiation RAT.

• Corrosion Science and Technology
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• 제7권2호
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• pp.77-84
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• 2008

Based upon the good compatibility to neutron irradiation and high temperature water environment, austenitic stainless steels are widely used for core internal structural materials of light water reactors. But, recently, intergranular cracking was detected in the stainless steels for the core applications in some commercial PWR plants. Authors studied on the root cause of the intergranular cracking and developed the countermeasure including the alternative materials for these core applications. The intergranular cracking in these core applications are defined as an irradiation assisted mechanical cracking and irradiation assisted stress corrosion cracking. In this paper, the root cause of the intergranular cracking and its countermeasure are summarized and discussed.

• E2M - 전기 전자와 첨단 소재
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• 제10권5호
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• pp.461-466
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• 1997

In this paper, we developed the new non-rubbing liquid crystal (LC) alignment techniques in the cell with slanted non-polarized ultraviolet (UV) light irradiation on polyimide (PI) film. It is shown that the uniform alignment for nematic (N) LC is obtained by using slanted non-polarized UV light irradiation on PI surface. We successfully obtained that the pretilt angle of NLC is generated about 3.3 degree in the cell with slanted non-polarized UV light irradiation with 70 degree on PI surface, for the first time. It is considered that the pretilt angle generation in NLC is attributed to interaction between the LC molecular and the PI, which is broken the polymer by slanted non-polarized UV irradiation. Therefore, we concluded that the uniform LC alignment is attributed to anisotropic dispersion force due to photo depolymerization with slanted non-polarized UV light irradiation on PI surface.

• 한국조리학회지
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• 제8권3호
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• pp.249-257
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• 2002

Gamma irradiation(1~10 kGy) was applied to chicken for the evaluation of their microbiological safety. In 3kGy-irradiated sample, the initial level of microbial contamination in chicken was 1.8$\times$10$^4$CFU/g (Coliforms), 2.2$\times$10$^3$CFU/g(Salmonella) and 2.7$\times$10$^3$CFU/g(Listeria), All kinds of contaminated microorganism were sterilized by 7kGy-irradiation. Also, irradiation followed by freeze storage at the same time was very effective in inhibiting bacterial growth. The pH was slightly increased during storage period and titratable acidity decreased. However, no significant changes in pH and acidity were observed by gamma irradiation.