• 대한소아치과학회지
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• 제35권3호
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• pp.446-455
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• 2008

이 연구의 목적은 법랑질 탈회부위에 불소 바니쉬 적용의 효과를 평가하는 것이다. 80개의 소의 법랑질 블록을 무작위로 4군으로 나누었다. 1군은 대조군으로 바니쉬 적용을 하지 않았다. 2군은 APF gel을 도포하고 4분후에 세척하였다. 3군과 4군은 Fluor $Protector^{(R)}$와 $CavityShield^{TM}$를 도포하고 1분 후에 세척하였다. 모든 표본을 인공우식용액 속에 넣어서 탈회시켰다. 가시광선 형광을 이용해 병소의 광밀도를 측정하고 병소의 깊이를 현미경으로 측정하고 통계적으로 비교하였다. 1. 48시간 후 광밀도 측정시 2군 광밀도는 대조군에 비해서 높았으나 바니쉬군보다 낮았고, 두 가지 바니쉬 간에 유의한 차이는 없었다. 2. 72시간 후 광밀도 측정결과 3군에서만 약간의 광밀도 감소가 관찰되고, 4군이 가장 높았다. 3. 72시간의 탈회 후 병소의 깊이를 측정한 결과 대조군에서는 평균 $205.36{\pm}42.85{\mu}m$, 2군에서 병소의 평균깊이는 $210.81{\pm}44.60{\mu}m$로 두 군간에 유의한 차이는 없었다. 4. 불소 바니쉬군의 병소 깊이는 3군이 $80.03{\pm}21.66{\mu}m$, 4군이 $77.46{\pm}27.72{\mu}m$로 대조군이나 2군에 비해 탈회가 억제되었음을 알 수 있었으나 두 가지 바니쉬 사이에 차이가 없었다.

• 대한화학회지
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• 제22권1호
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• pp.45-51
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• 1978

$77^{\circ}C$K 에탄올 매트릭스에서 N-메틸루티돈의 발광에 대한 연구를 하였다. 형광은 관찰되지 않았으나 양자 수득률이 0.1과 수명 0.2초의 강한 인광이 관찰되었다. 인광의 0-0 띠로부터 이 화물합의 삼중상태 에너지가 85.1kcal/mole임을 알았으며 2-헥센, 트란스-1,4-디클로로부텐-2와 같은 높은 삼중상태 에너지를 가진 올레핀들이 N-메틸루티돈에 의해 효과적으로 시스${\leftrightarrow}$트란스광이성질화 반응을 일으키는 것으로 보아 이 높은 삼중상태 에너지가 정당함을 알 수 있다. 0-0띠의 polarization이 음의 값을 갖는 것으로 부터 발광상태가 $({\pi},{\pi})^3$ 상태임을 알 수 있다. LiCl과 같은 알카리염의 양이온과 N-메틸루티돈이 배위결합을 함으로써 $({\pi},{\pi})^3$와 $(n,{\pi})^3$상태 사이의 에너지 차이가 크게 되기 때문에 알카리 금속염은 인광의 세기를 증가시킨다.

• 한국식품과학회지
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• 제42권5호
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• pp.521-526
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• 2010

본 연구에서는 우유에서 플루오르퀴놀론계 합성 항균제의 확인과 정량을 위하여 HPLC를 이용한 방법을 개발하였다. 우유 내 단백질을 제거하기 위하여 삼염화초산을 사용하였고 아세토니트릴로 추출하였다. 그리고 $Strata^{TM}$-X 카트리지로 정제한 후 $C_{18}$ 칼럼을 이용한 HPLC로 분석하였다. 높은 감도를 얻기 위하여 형광 검출기를 사용하였고, 최적파장 Ex: 278 nm, Em: 456 nm에서 분석한 결과 우유 내에서 정량한계와 회수율은 각각 ofloxacin 40 ${\mu}g$/kg, 73.6-95.2%, norfloxacin 10 ${\mu}g$/kg, 77.3-91.9%, ciprofloxacin 20 ${\mu}g$/kg, 91.6-94.3%, enrofloxacin 10 ${\mu}g$/kg, 81.0-87.8%, sarafloxacin 10 ${\mu}g$/kg, 71.3-81.0%, orbifloxacin 10 ${\mu}g$/kg, 89.4-90.8%, danofloxcin 2 ${\mu}g$/kg, 69.4-85.5%이었다.

• Journal of Photoscience
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• 제9권2호
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• pp.74-77
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• 2002

Chlorophyll (Chi) d was assigned to an antenna pigment of red algae in 1943, but its presence and function in red algae have not been necessarily clear for a long time. In 1996, it was shown that Chi d functioned as a major antenna pigment in a peculiar oxygenic photosynthetic prokaryote, Acaryochloris marina, isolated as a symbiont of a colonial ascidian from coral reefs. This finding evoked the necessity for reexamination of the presence and function of Chi d in red algae. We found Chi d in methanol-extract from several marine red algae, and the relative content was high in one species, Ahnfeltiopsis flabelliformis. Absorption and fluorescence spectra, HPLC analysis, and NMR and mass spectroscopy characterized Chi d extracted from the red algal thalli, and those were essentially identical to those of Chi d isolated from A. marina. However, micro-spectrophotometric analysis suggested that Chi d was not an actual constituent of the red algae but came from epiphyte(s) attached to surface of red algal thalli.

• 한국식품과학회지
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• 제34권4호
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• pp.541-545
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• 2002

Monascus pilosus KCCM 60084로부터 생성되는 색소의 공기에 대한 안정성 및 색소용액의 온도, pH, 빛 및 염류에 대한 안정성을 조사하였다. Monascus 색소는 공기 중에 30일간 방지할 경우 77.9%, 감압하에서는 48.4%가 감소하였다. Monascus 색소는 $20{\sim}80^{\circ}C$에서는 비교적 안정하였으나 $100{\sim}121^{\circ}C$에서는 $6.0{\sim}11.6%$의 감소율을 나타내었다. Monascus 색소는 pH $4{\sim}8$에서는 안정하였으나 pH 3과 9에서의 감소율은 각각 15.5% 및 13.7%이였다. Monascus 색소는 암소에서는 안정하였으나 형광하에서 30일 동안 둔 경우는 22.9%, 태양광 하에서는 68.8%가 감소하였다. 또한 Monascus 색소는 KCI, NaCI, $CaCl_2$, $MgCl_2$ 및 $ZnCl_2$에서는 비교적 안정하였으나 0.1 M $AlCl_3$ 용액에서는 20.3%의 감소로 불안정하였다.

• 한국결정성장학회지
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• 제25권6호
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• pp.252-256
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• 2015

질소산화물 ($NO_X$)은 고정원(화력발전소, 산업시설) 및 이동원(자동차, 선박) 등에서 배출되어지며, 발암물질 및 광화학 스모그의 주범으로 작용하고 있다. 선택적 촉매 환원법(SCR)은 $NO_X$를 제거하는 가장 효율적인 방법이며, 상업용으로 사용되어지는 $V_2O_5-WO_3/TiO_2$계 촉매에서 $V_2O_5$ 함량은 0.5~3 wt%, $WO_3$ 함량은 5~10 wt%이다. 촉매 성분 중 $V_2O_5$의 경우 $NO_X$ 환원 반응을 통해 촉매 작용을 촉진시키지만, 과량으로 첨가될 경우, $SO_2$에서 $SO_3$로의 산화 반응을 증가시킨다. 본 연구에서는 높은 탈질 효율을 유지시킴과 더불어, 바나듐의 함량을 줄이기 위하여, 그래핀을 바나듐 담지 matrix로 사용하여 나노복합체를 합성하였으며, 합성된 나노복합체를 첨가하여 Honeycomb형 1 inch SCR 촉매를 제조하였다. 제조된 SCR 촉매는 XRD(X-ray Diffraction), XRF(X-ray Fluorescence Spectrometer), BET(Brunauer, Emmett & Teller) 등의 분석을 통해 물성 평가를 진행하였으며, Micro Reactor(MR)를 이용하여 활성평가를 진행하였다. 그 결과, 촉매 상용 운전 온도인 $350^{\circ}C$에서 나노복합체가 첨가된 SCR 촉매의 탈질 효율은 77.1 %로 상용촉매의 탈질 효율인 77.8 %와 유사한 효율을 나타내는 것을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1173-1178
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• 2008

A simple and sensitive high-performance liquid chromatographic method was developed for the simultaneous identification of enrofloxacin and its active metabolite ciprofloxacin in chicken muscle. Norflorxacin imprinted polymers synthesized in water-containing systems show high selectivity to enrofloxacin and ciprofloxacin in an aqueous environment. Using these water-compatible imprinted polymers as selective adsorbents in the solid-phase extraction of enrofloxacin and ciprofloxacin from chicken samples, the remaining biological matrix could be quickly washed out from the imprinted column while enrofloxacin and ciprofloxacin were selectively retained and enriched. Analytical separation was performed on a $C_{18}$ column using acetonitrile-water as a mobile phase and fluorescence detection. Good linearity was obtained from 0.8 to 500 ng/g (r > 0.998) with relative standard deviation of less than 3.9%. The mean recoveries of enrofloxacin and ciprofloxacin from chicken muscle were 80.6-94.5% and 77.8-91.8% at three different concentrations. The limits of determinations based on S/N=3 were 0.07 ng/g and 0.09 ng/g, which are below the maximum residue limits established in many countries.

• 한국토양비료학회지
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• 제46권6호
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• pp.659-664
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• 2013

The aim of this study is to determine the drought stress index through photochemical analysis in red pepper (Capsiumannuum L.). The photochemical interpretation was performed in the basis of the relation between Kautsky effect and Photosystem II (PSII) following the measurement of chlorophyll, pheophytin contents, and $CO_2$ assimilation in drought stressed 5-week-old red pepper plants. The $CO_2$ assimilation rate was severely lowered with almost 77% reduction of chlorophyll and pheophytin contents at four days after non-irrigation. It was clearly observed that the chlorophyll fluorescence intensity rose from a minimum level (the O level), in less than one second, to a maximum level (the P-level) via two intermediate steps labeled J and I (OJIP process). Drought factor index (DFI) was also calculated using measured OJIP parameters. The DFI was -0.22, meaning not only the initial inhibition of PSII but also sequential inhibition of PSI. In real, most of all photochemical parameters such as quantum yield of the electron transport flux from Quinone A ($Q_A$) to Quinone B ($Q_B$), quantum yield of the electron transport flux until the PSI electron acceptors, quantum yield of the electron transport flux until the PSI electron acceptors, average absorbed photon flux per PSII reaction center, and electron transport flux until PSI acceptors per cross section were profoundly reduced except number of QA reducing reaction centers (RCs) per PSII antenna chlorophyll (RC/ABS). It was illuminated that at least 6 parameters related with quantum yield/efficiency and specific energy fluxes (per active PSII RC) could be applied to be used as the drought stress index. Furthermore, in the combination of parameters, driving forces (DF) for photochemical activity could be deduced from the performance index (PI) for energy conservation from photons absorbed by PSII antenna until the reduction of PSI acceptors. In conclusion, photochemical responses and their related parameters can be used as physiological DFI.

• 한국환경복원기술학회지
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• 제14권1호
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• pp.77-88
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• 2011

This study was carried out to investigate the effects of soil depth and planting density on the growth of lettuce, crown daisy, and strawberry on a rooftop condition using artificial soil as a growth media. The vegetable crops showed better growth for plant height (cm), plant width (cm), plant fresh weight (g), and Fo, Fm and Fv/m on 20cm depth soil than 10cm depth soil except strawberry. Planting density of $16/m^2$ and $64/m^2$ did not show significant differences on the growth of the crops. Soil moisture content and EC were low for 10cm depth soil in lettuce plots, whereas there was no significant differences on soil moisture and EC between two soil depth in strawberry plots. Hunter's L, a, and b values showed the leaf color of lettuce dark green on 20cm depth soil and reddish on 10cm depth soil. Results showed that soil depth suitable for crop growth on rooftop conditions was 20cm rather than 10cm. Growth response of the crops showed no significant difference between $16/m^2$ and $64/m^2$, indicating that planting density of 64 $plants/m^2$ could be practiced on rooftop conditions. Lettuce growth rapidly changed in control treatment in which leaves were not pinched out, while slowly changed in plants which leaves were periodically pinched out. In the case of control plot, it was impossible to harvest because withering of lower leaves after blossom on June 22. The plant of crown daisy in which pinching was not conducted, blossomed on June 7, and the plants were removed since its aesthetical value was lost. Strawberry seemed to be a suitable vegetable crop for rooftop conditions based on its high covering rate and extended growth period until late October. The soil depth 20cm and planting density 64 $plants/m^2$ were suitable for vegetable crops on green roof system using artificial soil.

• Toxicological Research
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• 제23권1호
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• pp.39-46
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• 2007

The aim of the study was to see if there is any differences in urinary 1-hydroxypyrene glucuronide (1-OHPG) and 2-naphthol levels in children ($8{\sim}14$ years old) and their mothers ($30{\sim}46$ years old) living three cities in South Korea (Seoul, Incheon and Pohang) and three in China (Changchun, Datong and Kunming), where the levels of air pollution varies. The factors related with urinary biomarkers levels were also evaluated. The study subjects consisted of 118 Korean (60 children and 58 their mothers) and 120 Chinese (60 children and 60 their mothers). Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy after immuno-affinity purification using monoclonal antibody 8E11 and urinary 2-naphthol concentrations were determined by HPLC with fluorescence detector. Information on recent consumption of diet containing high PAHs, environmental tobacco smoke (ETS), type of cooking and heating fuels, and other life-style characteristics were collected by self-administered questionnaire. The arithmetic mean of urinary 1-OHPG levels (n = 120, $mean{\pm}SD$, $6.77{\pm}7.96{\mu}mol/mol$ creatinine) in Chinese were 10 fold higher than those in Korean (n = 118, $0.62{\pm}0.61{\mu}mol/mol$ creatinine) (P < 0.01). Urinary 2-naphthol levels in Chinese (n = 119, $59.50{\pm}82.29{\mu}g/g$ creatinine) were significantly higher than those in Korean (n = 117, $25.09{\pm}46.56{\mu}g/g$ creatinine) (P < 0.01). Urinary 1-OHPG and 2-naphthol levels were significantly higher in children living the polluted cities in China (Datong and Chanchun, respectively). Multiple linear regression analysis indicated that living in factory area (vs. residential area) and use of coal stove as heating fuel were significant predictors for urinary 1-OHPG (overall model $R^2$= 0.46, n = 204). And ETS was predictor for urinary 2-naphthol levels in Korean ($R^2$ = 0.36, n = 46). These results indicated that urinary 1-OHPG and 2-naphthol levels were related with different ambient particulate air pollution, type of heating fuels and ETS.