• 식물병연구
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• 제21권3호
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• pp.193-200
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• 2015

Gray mold caused by Botrytis cinerea is one of the most important postharvest fungal pathogens of cut flowers. Here, gamma irradiation, an alternative for phytosanitary purposes, and sodium dichloroisocyanurate (NaDCC) were used to control B. cinerea in a cut chrysanthemum (Chrysanthemum morifolium Ramat.) cultivar, 'Baekma', one of the cultivars susceptible to B. cinerea. Spore germination and mycelium growth of B. cinerea were inhibited by gamma irradiation in an inversely dose-dependent manner. A dose of 4 kGy completely inhibited the mycelium growth of B. cinerea. A significant change in flower quality (physical properties) on chrysanthemum was shown from gamma irradiation at over 0.2 kGy (p<0.05). Therefore, in this study, the integration of gamma ray (below 0.2 kGy) and NaDCC, an eco-friendly form of chlorine, was investigated to control the disease with low dose of gamma irradiation dose. Interestingly, the gamma irradiated flowers showed more disease severity than the non-irradiated flowers. The combined treatment of gamma irradiation and NaDCC does not affect the severity of the fungal disease, whereas only 70 ppm of NaDCC treatment showed a significantly reduced severity. These results suggest that only chlorination treatment can be applied to control B. cinerea in cut chrysanthemum flowers.

• 한국축산식품학회지
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• 제33권5호
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• pp.603-609
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• 2013

The purpose of this study is to evaluate the change of volatile compounds in Dakgalbi cooked by charcoal broiling. Fresh deboned and marinated chicken meat was cooked by electric-pan frying or charcoal broiling and subsequently irradiated with a dose of 0, 10 and 20 kGy. Volatile components from Dakgalbi were analyzed using solid phase micro-extraction gas chromatography - mass spectrometry (SPME GC-MS) and identified through the comparison of mass spectrum database. SPME GC-MS analysis shows that a total of 32 volatiles were identified. Among them, aldehydes such as hexanal and octanal, which have relevance to off-flavors such as green, paint, metallic, bean and rancid were detected in Dakgalbi cooked by both methods. However, the contents were less detected in the Dakgalbi cooked by charcoal broiling than in the Dakgalbi cooked by electric-pan frying. Gamma-irradiation caused the change in the formation of these aldehydes in cooked Dakgalbi. The irradiation significantly increased the contents of hexanal and octanal in Dakgalbi cooked by electric-pan frying and a similar increase was found in Dakgalbi cooked by charcoal broiling. However, the contents of the off-flavors were much less in the latter. The results suggest that charcoal broiling might be more effective than electric-pan frying for the reduction of the contents of off-flavor such as hexanal and octanal increased in Dakgalbi by gamma-irradiation.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1556-1568
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• 2021

The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect stress conditions, mechanical behaviors and thermal-hydraulic performance of the fuel assembly. This paper is the Part II work of a two-part study devoted to analyzing the complex unique mechanical deformation and thermal-hydraulic characteristics for the typical plate-type fuel assembly under irradiation effect, which is on the basis of developed and verified numerical thermal-fluid-structure coupling methodology under irradiation in Part I of this work. The mechanical deformation, thermal-hydraulic performance and Mises stress have been analyzed for the typical plate-type fuel assembly consisting of support plates under non-uniform irradiation. It was interesting to observe that: the plate-type fuel assembly including the fuel plates and support plates tended to bend towards the location with maximum fission rate; the hot spots in the fuel foil appeared at the location with maximum thickness increment; the maximum Mises stress of fuel foil was located at the adjacent location with the maximum plate thickness increment et al.

• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.243-248
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• 1999

Ultrasonic wave technology was employed to improve filtration performance and ethanol production in a bioreactor equipped with an internal ceramic-membrane filter module. The filtration performance was found to depend on the power and the pattern of ultrasonic wave irradiation. Under the optimized conditions (irradiation time: 25 see, period: 5 min, and ultrasonic power: 60 W), the flux was improved with the periodic-pause method by 200-700％ compared with the control (with no irradiation), while the improvement was only 30 to 90％ without the periodic-pause method. The final ethanol concentration also increased slightly. However, in a more severe condition (irradiation time: 2.5 min, period: 5 min, and ultrasonic power: 110 W), the irradiation of ultrasonic waves was observed to disturb cell integrity and viability, and thus to decrease ethanol production.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.265-265
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• 2013

We have investigated the influences of dangling bonds generated by alpha particle irradiation on friction and adhesion properties of graphene. Single layer of graphene grown with chemical vapor deposition on copper foil was irradiated by the alpha beam with the average energy of 3.04 MeV and the irradiation dosing between $1{\times}10^{14}$ and $1{\times}10^{15}$/$cm^3$. Raman spectroscopic showed that the ${\pi}$ electron states below Fermi level arises and the $I_D$/$I_G$ increases as increasing the dosing of alpha particle irradiation. The core level X-ray photoelectron (XPS) revealed that these defects represent the creation of various carbon-related defects and dangling bond. The nanoscale tribological properties were investigated with atomic force microscopy in ultrahigh vacuum. The friction appeared to increase remarkably as increasing the amount of dosing, indicating that the dangling bonds on graphene layers enhances the energy dissipations in friction. This trend can be explained by the additional channel of energy dissipation by dangling bond or O- and H- terminated clusters created by alpha particle irradiation.

• 방사선산업학회지
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• 제7권2_3호
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• pp.149-154
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• 2013

In this study, the simple preparation of poly(sodium 4-styrenesulfonate) (PSS)-patterned substrate via a selective ion irradiation was investigated to manipulate cell adhesion. PSS thin films spin-coated onto the hydrophobic polystyrene (PS) was patterned through masked 150 keV proton irradiation followed by developing with deionized water. The characteristics of the resulting PSS-patterned surfaces were investigated by using microscope, surface profiler, FT-IR, XPS, and contact angle analyzer. These analytical results revealed that the resolved $100{\mu}m$ PSS patterns were formed on the hydrophobic PS surface above the fluence of $1{\times}10^{15}ions\;cm^{-2}$ and the chemical structure, composition, and wettability of the PSS patterns were dependant on a fluence. Moreover, the results of the in-vitro cell culture and proliferation assay exhibited that H1299 cells preferentially adhered and proliferated onto the more hydrophilic PSS part of the PSS-patterned PS and the well-aligned cell patterns was formed on the PSS-patterned PS particularly at the fluence of $1{\times}10^{15}ions\;cm^{-2}$.

• Nuclear Engineering and Technology
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• 제49권3호
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• pp.569-575
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• 2017

One of the important requirements for the application of reduced-activation ferritic/martensitic (RAFM) steel is to retain proper mechanical properties under irradiation and high-temperature conditions. To simulate the yield strength and stress-strain curve of steels during high-temperature and irradiation conditions, a multiscale simulation method consisting of both microstructure and strengthening simulations was established. The simulation results of microstructure parameters were added to a superposition strengthening model, which consisted of constitutive models of different strengthening methods. Based on the simulation results, the strength contribution for different strengthening methods at both room temperature and high-temperature conditions was analyzed. The simulation results of the yield strength in irradiation and high-temperature conditions were mainly consistent with the experimental results. The optimal application field of this multiscale model was 9Cr series (7-9 wt.%Cr) RAFM steels in a condition characterized by 0.1-5 dpa (or 0 dpa) and a temperature range of $25-500^{\circ}C$.

• 한국식품과학회지
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• 제49권5호
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• pp.544-549
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• 2017

본 연구는 폐자원인 커피박의 산업적 이용도를 증진시키기 위하여 감마선 조사를 이용하여 커피박 추출물의 색도 개선에 관하여 평가하기 위해 수행되었다. 커피박 추출물로부터 유용성 성분을 얻기 위하여 70% 에탄올로 추출한 후 감마선 조사를 한 결과 30, 50 kGy의 조사선량에서 커피박 추출물의 색도가 개선된 것을 확인하였다. 30, 50 kGy로 감마선 조사된 커피박 추출물에서 성분변화가 일어났지만, 항산화능력과 미백활성능에는 0 kGy 커피박 추출물 처리군과 비교했을 때 유의적인 변화가 없는 것을 확인하였다. 이는 다른 성분들이 감마선 조사에 의해 감소하였지만, 퀸산이 상당량 증가함으로써 성분변화로 인한 커피박 추출물의 생리활성능 감소를 보완한 것으로 보이며, 이상의 결과로 감마선 조사가 커피박 추출물의 진한 갈색도를 개선함으로써 커피박 추출물이 화장품 소재로 활융될 수 있는 부가가치를 부여 할 수 있으며, 이러한 폐기물의 재활용을 통해 커피박 폐기로 인한 환경문제 및 경제적 문제점을 개선하는데 기여할 수 있을 것으로 판단된다.

• 한국식품저장유통학회지
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• 제13권2호
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• pp.246-251
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• 2006

시판 유기질 퇴비(우분, 돈분, 계분 및 혼합분) 16종의 총 호기성 세균수, 대장균 및 대장균군 그리고 Salmonella에 대한 미생물 오염도를 파악하고, 미생물 오염도 저감화 및 위생성 향상을 위해 감마선을 조사한 후 미생물 사멸도를 측정하였다. 총 호기성 세균수는 우분, 돈분, 계분 및 혼합분의 경우 $10^4{\sim}10^\;CFU/g$으로 유의적인 차이를 나타내지 않았다. 대장균군은 16종의 시료 중 12종의 시료에서 $10^1{\sim}10^3\;CFU/g$의 분포를 나타내었고, 대장균은 3종의 시료에서 $10^1{\sim}10^2\;CFU/g$의 분포를 나타내었다. 또한 SS agar plate 분리 enteric group 미생물은 계분제품 중 1종에서만 검출되었다. 한편 총 호기성세균은 10 kGy 감마선 조사에 의해서 평균 4 log cycle 감소하였으며, 대장균군은 5 kGy 감마선 조사시 완전살균 수준의 감소효과를 나타내었다. E. coli와 SS agar plate 분리 enteric group은 3 kGy 감마선 조사에 의해 완전 사멸되었다. 유기질 퇴비 분포 미생물의 D값은 SS agar plate 분리 enteric group은 0.40 kGy, E. coli는 0.39 kGy의 범위를 나타내었다. 시판 유기질 퇴비는 3 kGy 수준에서 축분뇨발효 비료액의 병원성 미생물 공정규정을 충족할수 있으며, 위생화를 위해서는 5 kGy 수준으로 설정하는 것이 바람직할 것으로 사료된다.

• 한국축산식품학회지
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• 제29권1호
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• pp.34-39
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• 2009

저급미역에서 추출한 푸코이단/라미나린의 천연 항산화제로서의 이용 가능성을 평가하기 위해 돈육 패티에 이를 첨가하여 품질평가를 하였다. 푸코이단/라미나린 첨가 돈육 패티의 지질산패도를 측정한 결과 무첨가구에 비해 효과적으로 패티의 지질산화를 억제한 것으로 나타났으며, 이는 조사선량에 따라 지질산화 억제 효과가 증진하였다. 감마선 조사한 돈육 패티의 색도 변화를 측정한 결과, 시료 무첨가구와 라미나린 첨가구는 조사에 의한 유의적인 차이는 없었으나 푸코이단 처리구의 경우 패티의 조사선량이 증가함에 따라 명도가 증가하는 경향을 보였다. 돈육 패티에 푸코이단/라미나린을 첨가 하였을 때 패티의 보수성이 증가하여 경도가 감소하였으며, 이는 감마선 조사에 의한 유의적인 차이는 없는 것으로 나타났다. 그리고 감마선 조사와 푸코이단/라미나린 병용처리는 패티의 미생물을 제어하는 것으로 나타났다. 본 연구 결과 감마선 조사와 이 기술을 활용하여 추출한 푸코이단/라미나린을 병용처리 하였을 때 미생물학적 안전성을 확보하고 품질을 개선시켜 식품산업에서의 천연 항산화제로서 적용할 수 있을 것이라고 판단된다.