• 한국양식학회지
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• 제8권1호
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• pp.59-67
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• 1995

해산어류 종묘생산시 초기단계 먹이생물로서 많이 이용되고 있는 rotifer, Brachionus plicatilis의 large (L)-type, small (S)-type, thailand small (TS)-type에 대한 수온과 염분별 성장율, 최초산란 연령, 수명 및 총산란수 등에 관해 조사한 결과는 다음과 같다. 각 염분%$(5\%o,\;15\%o,\;25\%o,\;and\;35\%o)$에 따른 개체군 성장은 L-type은 $25^{\circ}C\;와\;29^{\circ}C$에서 비교적 양호한 성장을 보였으며 평균성장율은 $0.53\~0.71$이었고, S-type과 TS-type은 $29^{\circ}C$에서 각각 $0.81\~0.87,\;0.92\~1.04$였다. 최초산란연령은 3 type 모두 저염분, 고수온조건에서 빨랐으며 L-type은 $15\%o$구, $29^{\circ}C$에서 22.7시간, S-type은 $15\%o$구, $29^{\circ}C$에서 18시간, TS-type은 $5\%o$구, $29^{\circ}C$에서 18.8시간이었다. 총산란수는 3 type 모두 $25^{\circ}C$와 $29^{\circ}C$ 조건하에서 다산하였고, TS-type에 있어 $29^{\circ}C$에서 평균 28.3개체로 최대치를 나타냈고, S-type은 $15^{\circ}C$에서 평균 7.8개체로 가장 낮은 산란수를 나타냈다. 수명은 고수온에서는 짧고, 저수온에서는 길었으며 L-type과 TS-type에 있어 $15^{\circ}C$에서 평균 13.5일로 가장 길었고, S-type은 $29^{\circ}C$에서 평균 6.2일로 가장 짧았다.

• 한국수산과학회지
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• 제28권1호
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• pp.60-66
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• 1995

새로운 식중독 원인균으로 주목을 받고 있고 수권에서 잘 검출된다고 알려져 있는 V cholerae non-O1과 V. mimicus를 대상으로 민물, 기수 및 해수에서 염도와 온도의 변화에 따른 균수의 증감을 조사한 결과는 다음과 같다. 1. 민물에서 V. cholerae non-O1은 $26\pm1^{\circ}C$보다 4와 $15^{\circ}C$에서 생잔기간이 길었으며 V. mimius는 4와 $26\pm1^{\circ}C$보다 $15^{\circ}C$에서 생잔기간이 길었다. 2. 기수에서는 두 균주 모두 15, 4, $26\pm1^{\circ}C$으로 생잔기간이 길었다. 3. 해수에서는 두 균주 공히 온도가 높을수록 생잔기간이 짧았으며, $4^{\circ}C$에서 실험조건 중 생잔기간이 가장 길었다. 4. 민물에서는 V. mimicus보다 V. cholerae non-O1의 안정성이 높았고, 기수에서는 V. cholerae non-O1보다 V. mimicus의 안정성이 높았으며 해수에서는 두 균 사이에 큰 차이가 없었다. 5. 염도와 온도의 변화는 V. cholerae non-O1과 V. mimicus의 생잔에 중요한 인자이다.

• 한국환경과학회지
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• 제16권12호
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• pp.1425-1430
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• 2007

This study was conducted to investigate the effect of ozonated water and ozonated water+hydrogen peroxide treatment of residual procymidone in perilla leaf containing 20 mg/L procymidone. Samples was treated with ozonated water containing 1.0, 2.0 and 3.0 mg $O_3/L$ ozone and hydrogen peroxide water containing 1.0, 2.0 and 3.0 mg $H_2O_2/L$ hydrogen peroxide in pH 5, 7 and 9, respectively, at $15^{\circ}C$. Procymidone removal rate was 26.5% in 7 days at $15^{\circ}C$ and optimum condition of procymidone removal was the case of treating with ozonated water containing 2.0 mg $O_3/L$ and pH 9. As the result procymidone removal rate was about 96.5%. In this case of adding hydrogen peroxide, optimum condition of procymidone removal was $1:0.5{\sim}1(O_3:H_2O_2)$. However, procymidone was nearly removed with the treatment of hydrogen peroxide water only.

• 한국환경과학회지
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• 제15권5호
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• pp.471-477
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• 2006

We investigated the relationship between the $TiO_2$ photocatalytic decomposition of bisphenol A in water and biological toxicity to zebrafish (Danio rerio) during $1\sim28$ weeks post development stage. The bisphenol A in water was completely degraded by the $TiO_2$ photocatalysis in 50 hours. After the photocatalysis, no toxic effects on the morphogenesis of the zebrafish were observed during the development, growth, and maturate stages. Catalase activity of control group was not different from $1\sim5$ week post fertilized group. However, toxic effect on the catalase activity of adult stage(28 weeks) decreased 50% than control group.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.107-111
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• 2002

The OSS2 (Oj？me-Shavitt-Singer 2)[L. Oj？me et al., J. Chem. Phys. 109, 5547 (1998)] model for the solvated proton in water is examined for $H_2O,\;H_3O^+,\;H_5O_2^+,\;H_7O_3^+,\;and\;H_9O_4^-$ by molecular dynamics (MD) simulations. The equilibrium molecular geometries and energies obtained from MD simulations at 5.0 and 298.15 K agree very well with the optimized calculations.

• 생약학회지
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• 제51권1호
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• pp.55-64
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• 2020

In this study, 15 compounds were elucidated from the hot-water extract of Perillae Folium. Fifteen isolates were determined to be protocatechuic acid (1), caffeic acid (2), (R)-rosmarinic acid (3), (S)-shisoflavanone A (4), luteolin-7-O-β-D-glucuronopyranoside (5), scutellarein-7-O-β-D-glucuronopyranoside (6), apigenin-7-O-β-D-glucuronopyranosyl(1→2)-O-β-D-glucuronopyranoside (7), luteolin-7-O-β-D-glucuronopyranosyl(1→2)-O-β-D-glucuronopyranoside (8), kelampayoside A (9), trans-N-feruloyloctopamine (10), 3-(4-hydroxy-3-methoxyphenyl)-N-[2-(4-hydroxyphenyl)-2-methoxyethyl]acrylamide (11), perilloside C (12), perilloside A (13), (6S,9R)-9-hydroxy-megastigma-4,7-dien-3-one-9-O-β-D-glucopyranoside (14) and (6S,9R)-roseoside (15) through spectroscopic evidences. The HPLC analysis revealed that hot-water extract of Perillae Folium contained caffeic acid, rosmarinic acid and glycosides of apigenin, luteolin and scutellarein as main constituents.

• 상하수도학회지
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• 제12권1호
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• pp.52-61
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• 1998

Nitrification and denitrification are important processes in the landfill site as they are deeply related with degradation and stabilization of refuse. Also nitrous oxide ($N_2O$) which is released from both nitrification and denitrification is known as greenhouse gas (GHG). The purpose of this study was to clarify the process by which $N_2O$ produced using $^{15}N$ isotope. Nitrate which was labeled to 10.08% with $^{15}KNO_3$ was used and $N_2O$ was analyzed with GC mass. Results was that even also when $O_2$ of bulk was 15%, $N_2O$ was released from denitrification. And as concentrations of $O_2$ increase, sum of $N_2O$ was released from denitrification. And as concentrations of $O_2$ increase, sum of $N_2O$ and $N_2$ was decreased and ratios of $N_2O$ in the reduced gases were increased. FISH technics also adaped to confirm whether which of nitrifiers existed in the substrates. When NEU was used of which the target was ammonia oxidizing bacteria, nitrifier was not detected at all. So it was confirmed that during the reaction denitrification was dominant process. Total bacteria distributions which were detected by EUB probe explained that as $O_2$ increase the number of bacteria also increase, but between the 10-15% of $O_2$ there was no any differences.

• 대한환경공학회지
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• 제35권12호
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• pp.889-896
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• 2013

수중의 미량 유해물질 제거를 위해 AOP 공정에 대한 관심이 증대되고 있다. 낙동강 하류에 위치한 정수장들은 대부분 $O_3/BAC$ 공정을 채택하여 운전 중에 있으며, AOP 공정의 일종인 peroxone 공정의 적용에 많은 관심을 가지고 있다. 본 연구에서는 $O_3/BAC$ 공정을 운전 중인 정수장에서 과산화수소를 투입할 경우에 후단의 BAC 공정에서의 잔류 과산화수소의 제거 특성을 biofiltration 공정과 함께 평가하였다. 유입수의 수온 및 과산화수소 농도변화 실험에서 biofilteration 공정은 낮은 수온에서 유입수 중의 과산화수소 농도가 증가하면 급격히 생물분해능이 저하된 반면, BAC 공정에서는 비교적 안정적인 효율을 유지하였다. 유입수의 수온을 $20^{\circ}C$, 과산화수소 투입농도를 300 mg/L로 고정하여 78시간 동안 연속으로 투입한 실험에서 biofilteration 공정은 EBCT 5~15분의 경우 운전 24~71시간 후에는 유입된 과산화수소가 거의 제거되지 않았으나, BAC 공정에서는 78시간 후의 과산화수소 제거율이 EBCT 5~15분일 때 38%~91%로 나타났다. 또한, 78시간 동안 연속 투입실험 후의 biofilter와 BAC 부착 박테리아들의 생체량과 활성도는 각각 $6.0{\times}10^4CFU/g$과 $0.54mg{\cdot}C/m^3{\cdot}hr$ 및 $0.4{\times}10^8CFU/g$과 $1.42mg{\cdot}C/m^3{\cdot}hr$로 나타나 운전초기에 비해 biofilter에서는 생체량과 활성도가 각각 99%와 72% 감소하였으며, BAC의 경우는 각각 68%와 53%의 감소율을 나타내었다. BAC 공정에서 생물분해 속도상수($k_{bio}$)와 반감기($t_{1/2}$)를 조사한 결과, 수온 $5^{\circ}C$에서 과산화수소 농도가 10 mg/L에서 300 mg/L로 증가할수록 $k_{bio}$는 $1.173min^{-1}$에서 $0.183min^{-1}$으로 감소하였고, $t_{1/2}$은 0.591 min에서 3.787 min으로 증가하였다. 수온 $25^{\circ}C$의 경우 $k_{bio}$와 $t_{1/2}$은 $1.510min^{-1}$에서 $0.498min^{-1}$ 및 0.459 min에서 1.392 min으로 나타나 수온 $5^{\circ}C$에 비해 수온이 $15^{\circ}C$와 $25^{\circ}C$로 상승할 경우 $k_{bio}$는 각각 1.1배~2.1배 및 1,3배~4.4배 정도 증가하였다. $O_3/BAC$ 공정을 운전 중인 정수장에서 peroxone 공정의 적용을 위해 과산화수소 투입을 고려할 경우, 후단의 BAC 공정에서 잔류 과산화수소를 효과적으로 제거 가능하였고, 고농도의 과산화수소 유출사고시에는 BAC 공정의 EBCT를 최대한 증가시켜 운전할 경우 수중의 과산화수소 농도를 최대한 저감시킬 수 있을 것으로 판단된다.

• Advances in nano research
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• 제15권3호
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• pp.191-201
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• 2023

In order to develop better method to enhance and control the flow and heat transfer inside the radiator of electronic device, the synergistic effect of MHD nanofluids and porous medium on the flow and heat transfer in rectangular opened channel is simulated using Lattice Boltzmann method. Three nanofluids of CuO-water, Al₂O₃-water and Fe₃O₄-water are studied to analyze the influence of the type of nanofluid on the synergistic effect. The simulation results show that the porous medium can increase the flow velocity in fluid zone adjacent to the porous medium and enhance the heat transfer on the surface of the channel. Under no magnetic field, when the porosity of porous medium is 0.8, the Nusselt number is 4.46% higher than when the porosity is 0.9. Al₂O₃-water has the best heat transfer effect among the three nanofluids. At Ф=0.06, Ha=100, θ=90°, ε=0.9, Nu of Al₂O₃-water is 6.51% larger than that of CuO-water and 5.05% larger than that of Fe₃O₄-water. Magnetic field enhances seepage in porous medium and inhibits heat transfer in the bottom wall. When Ha=30 and 60, the inhibiting effect is the most significant as the magnetic field angle is 90°. And when Ha=100, the inhibiting effect is the most significant as the magnetic field angle is 120°.

• The Korean Journal of Physiology and Pharmacology
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• 제8권1호
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• pp.51-55
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• 2004

Sopungsungi-won has been used as a traditional medicine for diabetes and it has been proved to be a potential remedy for type 2 diabetes mellitus. We previously reported that water extract of Sopungsungi-won exhibits anti-diabetic effects both in vivo and in vitro experiments. In the present study, we have chosen to examined anti-apoptotic effect of Rheum undulatum, which is the main component of Sopungsungi-won, on pancreatic ${\beta}-cells$, HIT-T15, against hydrogen peroxide $(H_2O_2)$. oxidative stress. To investigate the anti-apoptotic effect of Rheum undulatum water extract (RUWE) against $H_2O_2-induced$ apoptosis in pancreatic ${\beta}-cell$ line of hamster, HIT-T15, MTT assay, DAPI staining, TUNEL assay, RT-PCR and caspase-3 enzyme assay were performed. The morphological analysis demonstrated that cells treated with $H_2O_2$ exhibited classical apoptotic features, while such changes was reduced in cells pre-treated with RUWE. In addition, RUWE pre-treated cells prior to $H_2O_2$ treatment induced increase of levels of bcl-2 expression and decrease of caspase-3 enzyme activity compared to cells treated with $H_2O_2$ only. These results provide the possibility of usage of RU in patients with progressively deteriorated diabetes.