• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1128-1131
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• 1999

Antioxidative and antimicrobial effects of the extracts of Castanea crenata leaf tea, steamed tea and semi-fermented tea were investigated. Antioxidative effects were by measuring the 1,1-diphenyl-2-picrylhydrazyl(DPPH)-radical scavening activity of the extracts. The effects were stronger than that of synthetic antioxidant such as BHT at the same concentration. The $SC_{50}$ value (50% radical scavening effects of $1{\times}10^{-4}$ M DPPH) of steamed tea, semi-fermented tea and BHT were 53.3 ${\mu}g/mL$, 49.9 ${\mu}g/mL$ and 101.0 ${\mu}g/mL$, respectively. The antimicrobial effects of methanol extracts (8 mg, 20 mg) of 0.2 g and 0.5 g. eq. of Castanea crenata leaf tea were stronger than those of 0.65 mg of benzoic acid, against gram(+) bacteria such as S. aureus, S. epidermidis, M. luteus, L. mesenteroides and B. subtilis and gram(-) bacteria such as E. coli, S. typhimurium, and P. aeruginosa.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.6 no.2
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• pp.35-44
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• 1986

This paper is a basic study of the experimental results for the treatment of ammonia-nitrogen in the septic tank effluent. The substrates in this experiment are actual septic tank effluent and synthetic waste-water which is similar to septic tank effluent containing a considerable amount of nitrogenous component. Experiments were conducted for organic removal and nitrification using various recycle ratio and hydraulic retention time at each stage. The results obtained show that organic removal rate was above 80% in the 1st and 2nd stage, but as nitrification process was proceeded, above 90% of ammonia-nitrogen was removed in the 3rd and 4th stage. In these cases, the recycle ratio and HRT were found 30 and 7 hrs respectively. In the relation of $NH_4{^+}-N$ removal to $NO_3{^-}-N$ formation in the synthetic waste-water and septic tank effluent, when $1mg/{\ell}$ of $NH_4{^+}-N$ was removed, $NO_3{^-}-N$ formations were $0.95mg/{\ell}$ and $0.82mg/{\ell}$ respectively. And kinetics of nitrification using Biological Fluidized Bed was discussed also.

• Journal of Korean Academy of Nursing
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• v.31 no.2
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• pp.268-278
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• 2001

Many women in the world have suffered from anemia produced by menstruation, pregnancy and delivery. In the theory of oriental medicine, a sour taste is believed to have a tonic effect on the blood. Thus this paper is to investigate the effect of sour tastes on the improvement in anemia-induced female mice, using citric acid and Fructus schizandrae(五味子). The method used in this experiment was the change of RBC, WBC, Hemoglobin, Hematocrit, Fe, and TIBC in the blood of female mice who were fed citric acid and Fructus schizandrae(五味子). The results obtained were as follows ; 1. Compared with the control group (anemia- induced group without treatment), the mean number of RBC in the blood of mice was significantly increased only in evaluating the change of sample group fed Fructus schizandrae (五味子) 500mg/kg. 2. Compared with the control group (anemia- induced group without treatment), the mean number of WBC in the blood of mice was not significantly larger in both sample groups fed citric acid and Fructus schizandrae(五味子). 3. Compared with the control group (anemia- induced group without treatment), the mean number of Hemoglobin in the blood of mice was significantly larger only in evaluating the change of the sample group fed Fructus schizandrae(五味子). 4. Compared with the control group (anemia- induced group without treatment), the mean percentage of Hematocrit in blood of mice was significantly increased only in evaluating the change of sample group fed Fructus schizandrae(五味子) 500mg/kg and sample group fed Fructus schizandrae(五味子) 250mg/kg for 3days. 5. Compared with control group (anemia- induced group without treatment), the mean volume of Fe in serum of mice was significantly increased only in evaluating the change of sample group fed Fructus schizandrae(五味子) 500mg/kg. 6. Compared with control group (anemia- induced group without treatment), the mean TIBC in serum of mice was significantly increased only in evaluating the change of sample group fed Fructus schizandrae(五味子) 500mg/kg and sample group fed Fructus schizandrae(五味子) 250mg/kg for 7days. According to these results, a sour taste is presumed to have a general tonic effect on anemia, but more study must be taken on the effects of citric acid in improving female anemia.

• Economic and Environmental Geology
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• v.34 no.6
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• pp.539-553
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• 2001

Geochemical data of the Han river water, including four tributary water samples in the main Han river are presented in this paper. The concentration of dissolved ions in the North Han river water decreases in order of Ca>Na>K>Mg and HCO$_3$>NO$_3$>SO$_4$>Cl, which it mainly affected by the chemical weathering of granite and gneiss in the drainage basin. Meanwhile, the South Han river water shows a decreasing order of Ca>Mg>Na>K and HCO$_3$>SO$_4$>NO$_3$>Cl, which is controlled by the bed rock geology of carbornate rooks and the inflow of acid mine drainage from the metal and coal mines in the Taebaegsan and Hwanggangri areas. The main Han river waters are characterized by unusually high concentration of Na, Cl and SO$_4$ (Ca>Na>K>Mg and HCO$_3$>SO$_4$>CI>NO), indicating a significant anthropogenic pollution by human activities in the metropolitan Seoul city. The geochemical data of the Han river waters from 1981 through 1996 to 1999 records a significant increase in SO$_4$ and NO$_3$, which responsible for the increasing arid mane drainage and municipal anthropogenic pollution.

• Journal of the Korean GEO-environmental Society
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• v.10 no.6
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• pp.27-33
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• 2009

In this study, it was analysed physical characteristics, TS, moisture, C/N ratio, leaching test, and element analysis in landfill wastes of 10 years old without landfill pretreatment. The Organic material content was 7.2%~23.5% and soil was the main inorganic materials which it's rate was 54.1%~71.0%, in landfill wastes. The results of TS, VS, and moisture were represented 51.5%~68.1%, 23.6%~56.1%, 32.0%~48.4%, respectively. The analysis of hazardous materials did not indicate Hg, $Cr^{+6}$, CN, Organic Phosphorus, TCE and PCE, however the Pb of leaching materials showed 0.023~0.092 mg/L, which was the highest. As the result of the element analysis, C was 47.74%~56.72%, N was 4.09%~9.92%, the C/N ratio was 5.76~12.57 and the result of soils around landfill was the highest heavy material, Pb, 2.465 mg/kg~10.251 mg/kg. The objectives of this paper are to investigate states, stabilization of these closed landfills and to gain suitable data for post-closure care using some parameters through analysis of landfill environment.

• Korean Journal of Optics and Photonics
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• v.31 no.3
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• pp.142-147
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• 2020

In this paper, we report highly efficient second harmonic generation of continuous-wave Yb fiber lasers incorporating a periodically poled LiTaO₃ device (MgO:PPSLT) as a frequency converter. The seed laser output from a Yb fiber master oscillator using a Fabry-Perot feedback cavity was amplified in a Yb fiber amplifier stage, yielding 28.5 W of linearly polarized output at 1064 nm in a beam with beam quality, M², of ~1.07. Second harmonic generation was achieved by passing the laser beam through MgO:PPSLT. Under optimized conditions, we obtained 11.1 W of green laser output at 532 nm for an incident signal power of 25.0 W at 1064 nm, corresponding to a conversion efficiency of 44.4%. The detailed investigation to find the optimized operating conditions and prospects for further improvement are discussed.

• Journal of dental hygiene science
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• v.8 no.4
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• pp.367-373
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• 2008

The natural products are used to be development of new antibacterial substances against human pathogenic bacteria. Adherence to the tooth surface by S. mutans is an important step in initiation of dental caries. This study was to examine antibacterial activity and anti-adhesive effect of Scutellaria baicalensis extract against S. mutans. Extracts of S. baicalensis were tested for antimicrobial activities by paper disc methods and radial diffusion assay methods, and bacterial adherence assay using 3 type of hydroxyapatite. The antibacterial level of ethyl acetate extract, IPK-3 on the growth of S. mutans was 125 mg/ml of minimum inhibitory concentration (MIC). The maximum growth of S. mutans in medium added with IPK-3 extract (50 mg/ml) was delayed to 30 hr, while the highest at 24 hr in control medium. The pH values of the control medium was 5.63 at 18 hr, but the media supplemented with IPK-3 extract was pH 6.50 at 12 hr. In adhesive inhibition assay, S. mutans was labelled with the fluorescent indicator DAPI and measured with fluorescence microscope. Adhesion of S. mutans on hydroxyapatite beads was inhibited by IPK-3 extracts. These results suggest that S. baicalensis extract can be used as an effective material for antibacterial activity and adhesive inhibition against S. mutans.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.89-99
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• 1998

약효(藥效) 및 안정성(安定性)이 입증(立證)된 한약(韓藥)으로부터 새로운 항균제(抗菌劑)를 도출(導出)하고자, 임상(臨床)에서 청열작용(淸熱作用)이 있거나 염증성(炎症性) 질환(疾患)과 박테리아의 감염(感染)으로 비롯된 질환(疾患)에 자주 쓰이는 22개(個)의 처방(處方)에 대(對)해 paper disk 법(法)을 사용(使用)하여 항균(抗菌) 효능(效能)을 검색(檢索)하였다. 시료(試料)는 한약(韓藥)의 고용(股用) 방법(方法)을 고려(考慮)하여 물로 추출(抽出)하였으며, 사용(使用) 균주(菌柱)로는 그람 양성균(陽性菌)인 포도상구균(葡萄狀球菌)과 고초균(枯草菌) 그리고 그람 음성균(陰性菌)인 대장균(大腸菌)과 녹농균(綠膿菌)을 사용(使用)하였고, 대조물질(對照物質)로는 tetracycline을 사용(使用)하여 상법(常法)에 의(依)해 실험(實驗)하였다. 22개(個)의 처방(處方) 가운데 백두옹탕(白頭翁湯), 황연해독탕(黃連解毒湯), 증황연황연해독탕(增黃連黃連解毒湯), 사심탕(瀉心湯), 용담사간탕(龍膽瀉肝湯), 선방활명음(仙方活命飮) 등(等)의 처방(處方)이 탁월(卓越)한 항균(抗菌) 활성(活性)을 보였다. 이 가운데 본(本) 연구(硏究)에서는 탕제(湯劑)의 구성(構成) 약재(藥材)가 다른 처방(處方)들에 비(比)해 비교적(比較的) 다양(多樣)한 선방활명음(仙方活命飮)에 대(對)해 활성(活性) 성분(成分)의 규명(糾明) 및 구성(構成) 약재간(藥材間)의 상화작용(相互作用)을 밝히고자 하였다. 선방활명음(仙方活命飮) 5 kg을 메탄올 (MeOH)로 추출(抽出)한 뒤 우수(優秀)한 항균(抗菌) 활성(活性)을 보인 에칠아세테이트 (EtOAc) 분획(分劃)에 대(對)하여 silica gel 및 Sephadex LH-20 column chromatography를 반복(反復)하여 stilbene 계열(系列)의 화합물(化合物)인 Rhapontigenin (Compound 1)과 Rhaponticin (Compound 2)을 얻었다. S. aureus SG 511에 대(對)해 Rhapontigenin은 50 mg/ml 이상(以上) 농도(濃度)에서 항균(抗菌) 효과(效果)를 나타내었고, Rhaponticin은 $200\;mg/m{\ell}$ 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었으며, B. subtilis ATCC 6633에 대(對)해 Rhapontigenin은 50 mg/ml 이상(以上) 농도(濃度)에서 항균(抗菌) 효과(效果)를 나타내었고, Rhaponticin은 200 mg/ml 농도(濃度)에서 우수(優秀)한 항균(抗菌) 효과(效果)를 나타내었으며, 100 mg/ml 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었다. 또한 E. coli 055에 대(對)해서는 Rhapontigenin과 Rhaponticin 모두 200 mg/ml 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었다. 이상(以上)의 결과(結果)로 보아 선방활명음(仙方活命飮)의 항균(抗菌) 효능(效能)은 군약(君藥)인 대황(大黃)의 성분(成分) 중(中)의 하나인 stilbene 계열(系列)의 화합물(化合物)인 Rhapontigenin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고 사료(思料)된다.

• The Journal of Engineering Geology
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• v.12 no.4
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• pp.471-484
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• 2002

Alluviums in the Keum River watershed cover an areal extent of $3,029{\;}\textrm{km}^2$ and contain about 8.1 billion tons of groundwater. However, the waters are severely polluted by nitrate, possibly due to the application of nitrogen fertilizer (>250 N kg/ha) on agricultural land. This paper aims to elucidate the pollution status and behaviors of nitrate in alluvial groundwaters in the Keum River watershed area, based on regional hydrogeochemical study. Most of the collected samples (n = 186) are polluted by nitrate (average = 42.2 mg/L, maximum = 295 mg/L). About 29% of the samples have the nitrate concentrations exceeding Korean Drinking Water Standard (44 mg/L $NO_3$). The distribution of nitrate concentrations in the study area is largely dependant on geochemical environments of alluvial aquifers. In particular, the decrease of redox potential of alluvial groundwaters showed a good correlation with the decreases of nitrate, iron, and manganese concentrations. Thus, the change of redox state in alluvial aquifers, likely reflecting their sedimentary environments, controls both the behavior and fate of nitrogen compounds and their natural attenuation (denitrification) in aquifers. A carbon-rich, silty layer within alluvium strata forms a reducing condition and possesses a buffering capacity on nitrate pollution.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.384-391
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• 2007

This study was conducted to clarify the effects of the Korean raisin (Hovenia dulcis Thunb) extracts and polyherbal extracts consisted of 6 types herbal extracts including HDT (HDTmix) on $CCl_4$ induced organ damages. Extracts were prepared by autoclave ($121^{\circ}C$, 15 psi, 3 hours) and filtered with nylon cloth and filter paper then freezing dried. Male Sprague-Dawley rats $(200^{\circ}{\ae}20g)$ were used as experimental groups, which were divided into 5 groups; intact control group (100 mg/kg), $CCl_4$ dosing group (100 mg/kg), $CCl_4$ dosing after HDT extract dosing group (100 mg/kg), $CCl_4$ dosing after HDTmix dosing group (100 mg/kg), Silymarin dosing group (5 mg/kg) after all test articles were orally dosed once a day for 28 days. They were sacrifiled under ether anesthesia. HDT extracts and HDTmix dramatically inhibits the $CCl_4$ intoxicated hepato/nephropathies with immuno-suppress changes on the spleen. They showed more dramatical protective effects on most of specific organs compared to that of Silymarin 5 mg/kg except for hepatoprotective effects in which, quite similar effects were detected. In addition, HDT extracts showed synergic effects with other types of herbal extracts because HDTmix showed more favorable protective effects on the all specific organs showing $CCl_4-related$ histopathological changes compared to HDT extracts.