• 한국환경과학회지
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• 제4권4호
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• pp.21-21
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• 1995

여러 파장의 광선(백색, 적색, 녹색 그리고 청색광)과 NAA, $GA_3$, BA 등의 식물호르몬을 옥수수와 녹두 유식물의 잎에 처리하여 환원당 축적과 invertase isozymes 활성에 미치는 효과를 조사하였다. NAA는 옥수수와 녹두 잎의 환원당과 invertase isozymes 활성의 증가를 촉진하였으나, $GA_3$는 환원당 축적과 효소의 활성증가에 효과적이지 못하였다. 한편 BA는 녹두 잎의 imvertase isozmes의 활성증가를 유도하는 반면, 옥수수 잎에 있어서는 큰 영향을 미치니 못하였다. 환원당의 축적에 있어서 적색광은 백색광에 비하여 효과적이였으나, invertase isozymes의 활성증가에 있어서는 여러 파장의 광선 모두가 촉진효과를 보여주지 않았다. 식물호르몬과 광선의 동시처리에 있어서 NAA와 백색광 동시처리는 녹두 잎의 환원당 축척 및 invertase isozymes의 활성증가에 매우 효과적이였으며 NAA와 청색광 동시처리는 옥수수 잎의 환원당 축척과 invertase isozymes의 활성증가에 매우 효과적이었다. 이상의 결과로 보아 옥수수와 녹두 잎의 환원다 축척 및 inverses isozymes의 활성증가에 있엇 식물호르몬, 큭히 NAA는 여러 파장의 광선보다 더 중요한 요인인 것으로 사료된다.

• 한국환경과학회지
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• 제4권4호
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• pp.323-333
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• 1995

여러 파장의 광선(백색, 적색, 녹색 그리고 청색광)과 NAA, $GA_3$, BA 등의 식물호르몬을 옥수수와 녹두 유식물의 잎에 처리하여 환원당 축적과 invertase isozymes 활성에 미치는 효과를 조사하였다. NAA는 옥수수와 녹두 잎의 환원당과 invertase isozymes 활성의 증가를 촉진하였으나, $GA_3$는 환원당 축적과 효소의 활성증가에 효과적이지 못하였다. 한편 BA는 녹두 잎의 imvertase isozmes의 활성증가를 유도하는 반면, 옥수수 잎에 있어서는 큰 영향을 미치니 못하였다. 환원당의 축적에 있어서 적색광은 백색광에 비하여 효과적이였으나, invertase isozymes의 활성증가에 있어서는 여러 파장의 광선 모두가 촉진효과를 보여주지 않았다. 식물호르몬과 광선의 동시처리에 있어서 NAA와 백색광 동시처리는 녹두 잎의 환원당 축척 및 invertase isozymes의 활성증가에 매우 효과적이였으며 NAA와 청색광 동시처리는 옥수수 잎의 환원당 축척과 invertase isozymes의 활성증가에 매우 효과적이었다. 이상의 결과로 보아 옥수수와 녹두 잎의 환원다 축척 및 inverses isozymes의 활성증가에 있엇 식물호르몬, 큭히 NAA는 여러 파장의 광선보다 더 중요한 요인인 것으로 사료된다.

• 대한치과보철학회지
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• 제38권3호
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• pp.291-309
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• 2000

Statement of problem. There were several studies on the effects of irradiation to peri-implant bone tissue. However, no clear biological effect of irradiation on peri-implant bone tissue was reported yet. Purpose. This study compared the effect of irradiation on the surrounding tissue of a HA-coated implant fixture with controls. Material and methods. 6 Steri-Oss implants were implanted into the femur of 6 mongrels. The implanted dogs were divided into three groups and received irradiation. After 1 month, 2months and 4 months healing period, the histologic examination and mobility test and digital radiographic imaging analyses were performed to compare the control and experimental group respectively. Results. The irradiated group showed slower healing than control group in light microscopic observations. The mobility test demonstrated significant less number (Periotest) in control group than that of irradiated groups. The digital radiographic imaging analysis showed that the bone density of irradiated group was higher than control group. Conclusion. Generally, control group showed favorable biological response and less mobility than irradiated group. The conflict result of bone density value were measured by the digital radiographic imaging analysis. The digital radiographic imaging analysis needs more research in future.

• 한국압력기기공학회 논문집
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• 제10권1호
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• pp.113-121
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• 2014

In this work, an integrated model including molecular dynamics and chemical rate theory was implemented to calculate the growth of point defect clusters(PDC) and copper-rich precipitates(CRP) which could change the mechanical properties of reactor pressure vessel(RPV) steels in a nuclear power plant. A number of time-dependent differential equations were established and numerically integrated to estimate the evolution of irradiation defects. The calculation showed that the concentration of the vacancies was higher than that of the self-interstitial atoms. The higher concentration of vacancies induced a formation of the CRPs in the later stage. The size of the CRPs was used to estimate the mechanical property changes in RPV steels, as is the same case with the PDCs. The calculation results were compared with the measured values of yield strength change and Charpy V-notch transition temperature shift, which were obtained from the surveillance test data of Korean light water reactors(LWRs). The estimated values were in fair agreement with the experimental results in spite of the uncertainty of the modeling parameters.

• Membrane and Water Treatment
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• 제8권3호
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• pp.211-223
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• 2017

In this work, an attempt was made to compare the effects of UV irradiation on the intrinsic and separation properties of membranes made of two different polymeric materials, i.e., polyvinylidene fluoride (PVDF) and polyetherimide (PEI). The changes on membrane structural morphologies and chemical characteristics upon UV-A exposure (up to 60 h) were studied by FESEM and FTIR, respectively. It was found that cracks and fractures were detected on the PVDF-based membrane surface when the membrane was exposed directly to UV light for up to 60 h. Furthermore, the mechanical strength and thermal stability of irradiated PVDF-based membrane was reported to decrease with increasing UV exposure time. The PEI membrane surface meanwhile remained almost intact throughout the entire UV irradiation process. Filtration experiments showed that the permeate flux of UV-irradiated PVDF membrane was significantly increased from approximately 11 to $16L/m^2.h$ with increasing UV exposure time from zero to 60 h. Oil rejection meanwhile was decreased from 98 to 85%. For the PEI-based membrane, oil rejection of >97% was recorded and its overall structural integrity was marginally affected throughout the entire UV irradiation process. The findings of this work showed that the PEI-based membrane should be considered as the host for photocatalyts incorporation if the membrane was to be used for UV-assisted wastewater treatment process.

• 한국전기전자재료학회논문지
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• 제15권7호
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• pp.627-633
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• 2002

Many isolated featureless domains were explicitly observed even at the air-water interface. We measured the surface pressure shift originating from the photo-isomerization of azobenzene units on the periphery of dendrimers. The maximum surface pressure was gradual1y increased and saturated by cyclic compression and decompression. By irradiation of 365 [nm] light, the surface pressure was increased, which was originated by the photo-isomerization process of the azobenzene group on the periphery from trans to cia form. The increase of the dipole moment ($\mu$), which may increase the interaction among Azo dendrimer molecules, made an important role on surface pressure shift. From the absorbance spectrum by UV irradiation and heat treatment, we can see that the absorbance in the UV region decreases with the increase of the UV irradiation time, but the peak at 350 m, characteristic of dendrimers in the LB monolayers, was not shifted until four irradiation cycles. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.

• International Journal of Oral Biology
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• 제33권4호
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• pp.137-141
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• 2008

The present study reports the protective properties of a total methanol extract of B. platyphylla var. japonica against ultraviolet (UV)-C irradiation. Pretreatment of Chinese hamster fibroblast (V79-4) cells with a total methanol extract significantly increased cell survival following $300\;J/m^2$ of UV-C irradiation. The total methanol extract was further fractionated into 5 fractions: n-hexane, dichloromethane, ethylacetate, n-butanol and water fractions. Among these fractions, B. platyphylla var. japonica ethylacetate, butanol and water fractions showed significant protective effects against the cellular damage induced by UV-C irradiation. In order to elucidate the mechanism underlying this protective effect, DPPH (Editor note: abbreviations should be spelled out at first use.) radical scavenging and lipid peroxidation inhibitory activity were measured. Significant radical scavenging and lipid peroxidation inhibitory activities were observed for the ethylacetate fraction. In summary, the present data demonstrate that an extract of B. platyphylla var. japonica has a significant protective effect against UV-C irradiation. The underlying mechanism of this protective effect may involve radical scavenging and inhibition of lipid peroxidation by the B. platyphylla var. japonica extract.

• 한국식물병리학회지
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• 제13권2호
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• pp.105-112
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• 1997

Didymella bryoniae, gummy stem blight fungus of cucurbits, has been known not to produce its pycnidium in vitro without irradiation. Various methods for producing pycnidiospores of the fungus as an inoculum have been used. However, those methods have not been verified in terms of efficiency of the productivity, activity and synchronous maturation of the inoculum. Therefore, a pycnidiospore production method in vitro that is highly reliable and reproducible has to be developed to obtain a large amount of inoculum for screening disease resistant varieties or effective fungicides. Here we standardized a mass-production technique for pycnidiospores of D. bryoniae in vitro by comprehensively finding the optimal conditions such as kinds and thickness of cultural medium, growing temperature, and quality and duration of irradiation as well as examining the activity and pathogenicity of the pycnidiospores reproduced. In brief, mycelial colony on the PDA plate was cultured at 26$^{\circ}C$ for 2 days under the darkness, and then the plate was irradiated under the UV light (12 hr/a day) for 2~3 days at the same temperature(26$^{\circ}C$). Two days after UV irradiation, a great number of pycnidia was simultaneously formed. This plate was subjected to darkness again for 4~5 days to mature pycnidiospores. We could obtain a large amount of inoculum that is synchronously matured in a short period of time through the above procedures.

• Toxicological Research
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• 제20권4호
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• pp.315-320
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• 2004

In this study we assessed the influences of ultraviolet (UV) light B radiation on epidermal ATPase-positive dendritic cell (DC) and the effect of green tea treatment in ICR mouse. The extent of changes following 200 mJ/$cm^2$ (0.5 mW/sec) was studied at 0, 6, 12, 18, 24, 30 or 36 hours after exposure. SBCs were decreased by 6 hours after irradiation. There was tendency to decrease from 6 hours to 24 hours and had little further change from then to 36 hours after irradiation. The mice that received 0, 50, 100, 200, 300 or 400 mJ/$cm^2$ of UVB were examined 24 hours after irradiation. The DCs were decreased as the radiation dose increases from 100 to 400 mJ/$cm^2$. The frequency of UVB (200 mJ/$cm^2$)-induced DC decrease was reduced by treatment of green tea (i.p. and topical application, p<0.01).

• 한국염색가공학회지
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• 제18권6호
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• pp.49-56
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• 2006

Surface treatment using UV irradiation was carried out to improve optical properties of polarizing films. The effects of UV energy of the UV-treated PVA films were investigated by measuring reflectance, surface roughness, contact angles, ESCA, and ATR. Reflectance decreased at wavelength of 450 nm or less and surface roughness increased with increasing UV energy. Water contact angle increased in the irradiated PVA films and surface energy decreased with increase in w energy. An analysis showed that the OH groups were broken and some new groups were introduced such as C=C and C=O bonds together with increased $O_{1s}/C_{1s}$, resulting in the observed surface modification effect. Surface modified PVA polarizing films showed improvement in light transmittance of polarizing films at high wavelength region without deteriorating polarization efficiency, which was not affected by UV irradiation sequence during manufacturing processes such as coloring and drawing.