• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.543-547
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• 2005

해수소통을 전제한 경우 새만금호 내측의 염분변화가 만경강의 평수량 및 홍수량 유입에 따라 혼합확산되는 것을 평가하고 배수갑문 방류시 담수가 외해에 미치는 영향범위를 평가하기 위한 수치모형실험이 실시되었다. 이때 새만금호 내부의 관리수위는 DL=-1.5m, DL=-0.5m, DL=-0.0m, DL=+0.5m가 고려되었다. 외해역의 평가는 새만금을 포함한 전체해역에 대해 외해경계에서 4개의 주요분조($M_2,S_2,K_1,O_1$)의 진폭과 위상각을 대입하고 2차원 ADCIRC 및 3차원 TIDE3D 모형을 적용하였다. 내부는 여기에 3개 연직층을 고려한 3차원 ICM 모델이 추가 적용되었다. 내부의 혼합확산 평가 결과는 시간이 지남에 따라 외해에서 유입되는 염수가 상대적으로 저염인 담수호 내부로 유입 확산되는 것이 평면적으로나 연직방향으로 변화되는 것을 매우 뚜렷하게 나타남을 알 수 있고, 최소 1개월 이상 경과되어야 만경호측에 외해수가 혼합되는 것으로 분석된다. 수문을 개방하지 않은 상태에서 새만금 방조제 외해의 최강창낙조시 조류속도는 0.5-0.6m/s 정도에 해당되는 것으로 분석되었다. 신시갑문을 개방하는 경우 관리수위가 DL=-1.5m와 DL=+0.5m로 변함에 따라 갑문 전면 10Km-l3Km에 이르는 해역까지 수문개방에 따라 0.5m/s의 유속이 형성된다. 가력갑문을 개방하는 경우는 신시갑문의 개방에 따른 영향보다는 작지만 갑문 전면 14Km까지 0.5m/s의 강한 유동이 관리수위별로 나타나고 있다. 이러한 결과는 담수 방류로 인한 영향이 주기적으로 낙조시에 발생되어 새만금 방조제 전면의 해수순환과 유동에 적지 않은 영향을 미칠 개연성을 제시하는 것으로 해석된다.$\cdot$유출에 의한 수질변화양상을 단계적으로 구분하여 수질변화에 중요한 영향을 미치는 인자에 대한 이론적인 분석을 수행하고, 배수갑문 개방에 의한 수질개선효과를 최대화하기 위한 환경관리 방안 제시에 중점을 두어 수행하였다.ncy), 환경성(environmental feasibility) 등을 정성적으로(qualitatively) 파악하여 실현가능한 대안을 선정하였다. 이렇게 선정된 대안들은 중유역별로 검토하여 효과가 있을 것으로 판단되는 대안들을 제시하는 예비타당성(Prefeasibility) 계획을 수립하였다. 이렇게 제시된 계획은 향후 과학적인 분석(세부평가방법)을 통해 대안을 평가하고 구체적인 타당성(feasibility) 계획을 수립하는데 토대가 될 것이다.{0.11R(mm)}(r^2=0.69)$로 나타났다. 이는 토양의 투수특성에 따라 강우량 증가에 비례하여 점증하는 침투수와 구분되는 현상이었다. 경사와 토양이 같은 조건에서 나지의 경우 역시 $Ro_{B10}(mm)=20.3e^{0.08R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.279-285
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• 2009

Antioxidant and antimicrobial efficiency were investigated for: i) water extract of green tea(Camellia sinensis), ii) water extract of middle drying megmoondong(Liriope platyphylla Wang et Tang) and iii) water extract of drying megmoondong. The electron donating ability of the green tea(Camellia sinensis) and drying megmoondong(Liriope platyphylla Wang et Tang) extract were 88 and 79, respectively, while that of the middle drying megmoondong extract showed low levels. The relative inhibitory abilities against lipid peroxidase were: green tea(Camellia sinensis) extract > drying megmoondong(Liriope platyphylla Wang et Tang) extract > middle drying megmoondong extract. The green tea(Camellia sinensis) extract showed the strongest antimicrobial effect against Staphylococcus aureus. The middle drying(Liriope platyphylla Wang et Tang) and drying megmoondong extracts showed no antimicrobial effect against Staphylococcus aureus. The green tea(Camellia sinensis) extract had the strongest antimicrobial effect against Escherichia coli. The middle drying megmoondong(Liriope platyphylla Wang et Tang) and drying megmoondong extracts showed no antimicrobial effect against Escherichia coli.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.57-63
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• 1992

The purpose of this study was to investigate the rheological and thermal properties of yam starch. Yam starch had a hydrodynamic volume with the intrinsic viscosity,［$\eta$］, of 0.29dl/g deionized water. The values of the intrinsic viscosity of yam starch, determined to pH 2-11, varied between 0.07 to 0.18 dl/g. The highest intrinsic viscosity was obtained at pH 7. At salt concentrations 0-0.2 M NaCl, the intrinsic viscosity of yam starch was decreased up to 0.05 M NaCl concentration then increased to 0.07 M NaCl concentration and remained constant to reach 0.2 M NaCl concentration. The overlap parameter, calculated with the intrinsic vicosity data, was 3.45 g/dl in deionized water. The thermal properties of yam starch were investigated by Differential Scanning Calorimetry. Three endotherms were observed both pH solution and salt concentation. In the presence of pH 9, the onset temperature of gelatinization peak was the lowest temperature of 50.$32^{\circ}C$ and the enthalpy ($\Delta$H) was increased in this solution. The effect of salt on the thermal properties of yam starch was determined at salt concetration of 0-0.2 M NaCl. The enthalpy significantly decreased to salt concentration 0.07 M NaCl and the lowest onset temperature of this concentration was 52.$90^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.260-266
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• 2013

Rhodococcus sp. strain p52, a previously isolated dibenzofuran degrader, could effectively inhibit the growth of cyanobacteria, including species of Microcystis, Anabaena, and Nodularia. When strain p52 was inoculated at the concentration of $7.7{\times}10^7$ CFU/ml, 93.5% of exponentially growing Microcystis aeruginosa ($7.3{\times}10^6$ cells/ml initially) was inhibited after 4 day. The threshold concentration for its algicidal activity against M. aeruginosa was $7.7{\times}10^6$ CFU/ml. Strain p52 exerted algicidal effect by synthesizing extracellular substances, which were identified as trans-3-indoleacrylic acid, DL-pipecolic acid, and L-pyroglutamic acid. The effective concentrations of trans-3-indoleacrylic acid and DL-pipecolic acid against M. aeruginosa were tested to be 0.5 mg/l and 5 mg/l, respectively.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.24-25
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• 2003

Lead is ubiquitous in the human environment as a result of industrialization. China's rapid industrialization and traffic growth have increased the potential for lead emissions. Lead poisoning in children is one of the most common public health problems today, and it is entirely preventable. Children are more vulnerable to lead pollution and lead in their bodies can affect their nervous, circulatory, and digestive systems. Children are exposed to lead from different sources (such as paint, gasoline, and solder) and through different pathways (such as air, food, water, dust, and soil). Although all children are exposed to some lead from food, air, dust, and soil, some children are exposed to high dose sources of lead. Significant sources of lead for China's children include industrial emissions (often close to housing and schools), leaded gasoline, and occupational exposure that occurs when parents wear lead-contaminated clothing home from work, burning of coal for home heat and cooking, contaminated food, and some traditional medicines. To assess the blood lead level in children in China, a large-scale study was conducted in 19 cities among 9 provinces during 1997 to 2000. There were 6502 children, aged 3-5 years, were recruited in the study The result indicates that the mean blood lead level was 8.83ug/dl 3-5 year old living in city area. The mean blood lead level of boys was higher than that of girls (9.1l ug/dl vs 8.73ug/dl). Almost 30 percent childrens blood lead level exceeded 10ug/dl. The average blood lead level was higher than that of in 1985 (8.83ug/dl vs 8.lug/dl). An epidemiological study was carried on the children living around the cottage industries recycling the lead from battery. Nine hundreds fifty nine children, aged 5-12 years, living in lead polluted villages where the lead smelters located near the residential area and 207 control children live in unpolluted area were recruited in the study. The lead levels in air, soil, drinking water and crops were measured. The blood lead and ZnPP level were tested for all subjects. The results show that the local environment was polluted. The lead levels both in the air and crops were much higher than that of in control area. In the polluted area, the average blood level was 49.6ug/dl (rang 19.5-89.3ug/dl). Whereas, in the unpolluted area, the average blood level was 12.4ug/dl (rang 4.6-24.8ug/dl). This study indicates that in some countryside area, some cottage industries induce seriously lead pollution and cause children health problem. For the introducing of unleaded gasoline in some large cities, such as Beijing and Shanghai, the blood lead level showed a declined trend since 1997. By 2000, the use of leaded gasoline in motor vehicles has been prohibited in China. The most recent data available show that levels of lead in blood among children in Shanghai decreased from 8.3ug/dl in 1997 to 7.6ug/dl in 1999. The prevalence rate of children lead poisoning (blood lead >10ug/dl) was also decreased from 37.8% to 24.8%. In children living in downtown area, the blood lead level reduced dramatically. To explore the relationship between gene polymorphisms and individual susceptibility of lead poisoning, a molecular epidemiological study was conducted among children living in lead polluted environment. The result showed that the subjects with ALAD2 allele has higher ZPP level, and the subjects with VDR B allele has larger head circumference than only with b allele. In the present study, we demonstrated that ALAD genotypes modify lead effects on heme metabolism and VDR gene variants influence the skull development in highly exposed children. The polymorphism of ALAD and VDR genes might be the molecular inherited factor modifying the susceptibility of lead poisoning. Recently, Chinese government pays more attention to lead pollution and lead poisoning in children problem. The leaded gasoline was prohibited used in motor vehicles since 2000. The government has decided to have a clampdown on the high-polluted lead smelters for recycling the lead from battery in countryside. It is hopeful that the risk of lead poisoning in children will be decreased in the further

• Journal of Electrochemical Science and Technology
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• v.5 no.1
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• pp.23-31
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• 2014

The DL-norvaline was electrochemically oxidized and deposited on the glassy carbon electrode surface using cyclic voltammetry (CV). The modified electrode was examined for electrochemical oxidation of hydroquinone (HQ) and catechol (CC). It exhibited good electrocatalytic ability towards their oxidation and simultaneous determination in a binary mixture using differential pulse voltammetry (DPV). The peak currents were linear to the concentration of HQ and CC, in the range from $5{\mu}M$ to $100{\mu}M$, and $4{\mu}M$ to $140{\mu}M$, respectively. The determination limits(S/N = 3) for HQ and CC were $1{\mu}M$ and $0.8{\mu}M$, respectively. The obtained modified electrode was applied to simultaneous detection of HQ and CC in water sample.

• Biomolecules & Therapeutics
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• v.11 no.2
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• pp.91-98
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• 2003

A new series of highly water soluble platinum(II) complexes[Pt(II)(DL-2-hydroxy-3-methylbutyrate)(trans-l-1,2-dimninocyc1ohexane)] (PC-1) and [Pt(II)DL-2-hydroxy-3-methylbutyrate](cis-1,2-diaminocyclohexane)](PC-2) were synthesized and characterized by their elemental analysis and by various spectroscopic techniques [infrared(IR), $^{13}C$-nuclear magnetic resonance (NMR)]. In vitro antitumor activity of new Pt(II)complexes was tested against MKN-45, MKN/ADM and MKN/CDDP human gastric adenocarcinoma cell lines using colorimetric MTT[3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazoliumbromide] assay for cell survival and proliferation. PC-1 and PC-2 showed active against MKN-45/P, MKN/ADM and MKN/CDDP human gastric cancer cell lines, and the antitumor activity of these compounds were comparable or superior to that of cisplatin. The nephrotoxicities of PC-1 and PC-2 were found quite less then that of cisplatin using MTT and [$^3H$] thymidine uptake tests in rabbit proximal tubule cells, human kidney cortical cells human renal cortical tissues. Based on these results, these novel platinum(II) complex compounds(PC-1 ＆ PC-2) represent a valuable lead in the development of the new anticancer chemotherapeutic agents capable of improving antitumor activity and low nephrotoxicity.

• Polymer(Korea)
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• v.27 no.4
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• pp.370-376
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• 2003

Poly(DL-lactide-co-glycolide) nanoparticles were prepared by the modified spontaneous emulsification solvent diffusion method. Polymer solution was prepared by two water-soluble organic solvents, such as ethanol and acetone. Because of its biocompatible nature, PEG-PPG diblock copolymer was used as surfactant and stabilizer. The influence of several preparative variables on the nanoparticle formation, such as type and concentration of stabilizing agent, stirring methods, water/oil phase ratio and polymer concentration were investigated in order to control and optimize the process. After preparation of nanoparticles, particle size and distribution were evaluated by the light scattering particle analyzer. As results, the particle size was 50-200 nm and dispersibility was monodisperse. It was found that the appropriate selections of binary solvent mixtures and polymeric concentrations in both organic and aqueous phases could provide a good yield and favorable physical properties of PLGA nanoparticles.

• Korean Journal of Clinical Pharmacy
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• v.5 no.2
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• pp.61-69
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• 1995

Hyperlipidemia is a major predisposing factor of atherosclerosis and cerebrovascular accidents. In effort to develope a hypolipidemic drug from medicinal herb, We tested three prescriptions of traditional medicine for the lipid lowering effect on diet-induced hyperlipidemic rats. GyejI-Bokryung-Hwan, Ohyak-Sunki-San, and Shihoga-Yongol-Moryu-Tang were selected based on the comnon prescriptions for patients with hyperlipidemia-related diseases. Water extract from each prescriptions was made by the method used in the clinical setting, and administered intragastrically once a day, for 4 weeks. Fenofibrate and lovastatin were given by the same method as the control drugs. Blood levels of total cholesterol(TC), high density lipoprotein(HDL), low density lipoprotein (LDL), and triglyceride(TG) were measured before, 1, 2, 3, and 4 weeks after starting the drug administration. All of the traditional prescriptions did not show lipid lowering effect, while fenofibrate lower the blood cholesterol levels(TC;from 215mg/dl before to 182m41 at 4 weeks-point of drug administration, and LDL ;from 203mg/dl before to aut 161, and 163mg/dl at 3 and 4 week-point respectively). Oyak-Sunki-San increased the level of TC (from 283mg/dl to over 350mg/dl starting from the first week of drug administratin). Effects on TG variable in the cases of traditional medicines and control drug In conclusion, any of the three traditional medical prescriptions did not decrease the level of blood cholesterol.

• Journal of the Korean Chemical Society
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• v.47 no.5
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• pp.479-486
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• 2003

In this study, poly(DL-lactide-co-glycolide) nanoparticles loaded with water-insoluble vitamins such as vitamin A (Retinol) and vitamin E acetate were prepared by the emulsification diffusion method. Polymer solution was prepared by the two water-miscible organic solvent, such as ethanol and acetone. Because of its biocompatible property, polyethyleneglycol-polypropyleneglycol diblock copolymer was used as surfactant and stabilizer. The influence of some preparative variables on the nanoparticle formation and on the loading efficiency of active agents, such as the type and concentration of stabilizing agent, the stirring methods, the water/oil phase ratio and the polymer concentration were investigated in order to control and optimize the process. After preparation of nanoparticles loaded with active agent, particle size and distribution were evaluated by the light scattering particle analyzer. The loading efficiency of active agents was evaluated by the UV-visible spectroscopy. As the results, particle size were 50-200 nm and dispersibility was monodisperse. The optimum loading efficiency of active agents was observed 50-60%. It was found that the appropriate of selections of binary solvent mixtures and polymeric concentrations in both organic and aqueous phases could provide good yield and favorable physical properties of PLGA nanoparticles.