• 한국환경과학회지
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• 제23권9호
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• pp.1655-1662
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• 2014

A comprehensive fractionation technique was applied to a set of water samples obtained along drinking water treatment process with ozonation and biological activated carbon (BAC) process to obtain detailed profiles of dissolved organic matter (DOM) and to evaluate the haloacetic acid (HAA) formation potentials of these DOM fractions. The results indicated that coagulation-sedimentation-sand filtration treatment showed limited ability to remove hydrophilic fraction (28%), while removal of hydrophobic and transphilic fraction were 57% and 40%, respectively. And ozonation and BAC treatment showed limited ability to remove hydrophobic fractions (6%), while removal of hydrophilic and transphilic fractions were 25% and 18%. The haloacetic acid formation potential (HAAFP)/dissolved organic carbon (DOC) of hydrophilic fraction was the highest along the treatment train and HAAFP/DOC of hydrophilic fraction was higher than hydrophobic and transphilic fraction as 23%~30%, because of better removal for hydrophobic fraction both in concentration and reactivity.

• Journal of Microbiology and Biotechnology
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• 제24권5호
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• pp.629-638
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• 2014

This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at $50^{\circ}C$ for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

• 한국식품과학회지
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• 제30권1호
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• pp.175-183
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• 1998

비타민 C 고함량의 물김치를 제조하기 위한 방법의 하나로 담금수의 종류를 달리하여 지하수, 1차증류수, 3차 증류수, 생수 및 수돗물의 금속이온(Ca, Mg, Fe, K, Na, Cu) 함량을 분석하였으며, 각각의 물로 열무 물김치를 제조하여 $15^{\circ}C$에서 발효 숙성시키면서 그 담금수가 김치의 숙성지표인 pH와 산도의 변화에 미치는 영향을 밝히고, 총 비타민 C함량, 텍스쳐 및 미생물 균수의 변화를 살펴봄과 동시에 관능검사를 실시한 결과는 다음과 같았다. 각 담금수의 금속이온 함량을 측정한 결과, 전반적으로 3차 증류수가 금속이온 함량이 가장 낮은 반면 수돗물은 금속이온 함량이 가장 높았고, 특히 Cu 이온이 검출되었으며, 지하수의 Ca함량은 다른 담금수에 비해 월등히 높았다. 각 담금수로 제조한 김치국물의 pH와 산도 및 미생물의 변화는 김치시료간에 큰 차이를 보이지 않았고, 열무 줄기로 측정한 텍스쳐는 시료간에 큰 차이를 보이지 않았으나 담금 3일까지 증가하였다가 그 이후 감소하는 경향을 보였다. 한편, 총 비타민 C 함량은 3차 증류수로 제조한 김치국물의 숙성 적기 총 비타민 C함량이 7.20 mg%로 최고 함량을 나타내었고, 그 다음이 지하수로 제조한 김치로 5.72 mg%를 나타내었으며, 수돗물로 제조한 김치의 총 비타민 C 함량은 3.37 mg%로 가장 낮아 3차 증류수로 제조한 김치의 50%에 불과했다. 또한, 기호도를 조사한 결과, 3차 증류수로 제조한 김치의 기호도가 가장 높았고 그 다음이 생수로 제조한 김치였으며, 지하수로 제조한 김치의 기호도가 가장 낮았다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.491-498
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• 2005

Acid Rock Drainage(ARD) is the product formed by the atmospheric(i.e. by water, oxygen and carbon dioxide) oxidation of the relatively common iron-sulphur minerals pyrite($FeS_2$). ARD causes the acidification and heavy metal contamination of water and soil and the reduction of slope stability. In this study the generation characteristics and the prediction of ARD of various road cut slopes were studied. An attempt to classify the rocks into several groups according to their acid generation potentials was made. Acid Base Accounting(ABA) tests, commonly used as a screening tool in ARD predictions, were performed. Sixteen rock samples were classified into PAF(potentially acid forming) group and four rock samples into NAF(non-acid forming) group. The chemical analysis of water samples strongly suggested that ARD with high content of heavy metals and low pH could pollute the ground water and/or stream water.

• 생약학회지
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• 제49권3호
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• pp.219-224
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• 2018

Artemisia annua L. (Compositae) is an annual herb, which has been traditionally used as an antipyretic and hemostatic agent with the herbal medicine name of Cheong Ho (菁蒿) in Korea and China. In this study, five di-caffeoylquinic acid derivatives and a coumarin were determined from the hot-water extract of aerial parts of A. annua. The structures of isolates were elucidated to be 1,3-di-O-caffeoylqunic acid (1), 3,4-di-O-caffeoylquinic acid (2), 3,5-di-O-caffeoylqiunic acid (3), 1,5-di-O-caffeoylquinic acid (4) and 4,5-di-O-caffeoylquinic acid (5) and scopoletin (6). The presence of 1,5-di-O-caffeoylquinic acid (4) is firstly reported from A. annua in the current study.

• 한국지반환경공학회 논문집
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• 제19권10호
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• pp.21-26
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• 2018

흙-습윤 특성곡선은 불포화토에서 물의 흐름, 다상유체에서의 상대투수계수, 그리고 흙의 강성 및 부피 변화를 이해하는데 필수적이다. 바이오폴리머는 미생물에 완전 분해가 가능한 자연에 무해한 친환경 물질이다. 따라서, 치토산, 폴리에틸렌 옥사이드, 잔탄검, 알지네이트염 및 폴리아크릴산 등과 같은 바이오폴리머가 지반복원, 지반성능향상 및 오일생산증진을 위해 연구되어왔다. 폴리아크릴산(polyacrylic acid)은 바이오폴리머의 일종으로, 유체의 흐름 특성 향상을 통하여 오일생산증진 및 지반복원 등의 분야에서 우수한 성능을 보여왔다. 따라서, 본 연구에서는 폴리아크릴산(polyacrylic acid)을 포함한 모래의 흙-습윤 특성곡선의 이해하기 위해서 실내시험을 수행하고, 이론적 모델의 매개변수 변화를 연구하였다. 그 결과, 폴리아크릴산(polyacrylic acid)의 농도가 증가함에 따라, 포화된 모래에 주입되는 공기의 주입 모세관압력이 증가함을 보이고, 높은 모세관압력에서의 잔류 함수비 역시 증가하고 있음을 보였다. 또한, 이론식 모델의 매개변수를 구하였으며, 이를 활용한 흙-습윤 특성곡선이 실내 실험 결과와 잘 일치하고 있음을 보였다. 따라서, 이론적 모델의 매개변수를 알고 있으면, 본 연구에서 활용된 폴리아크릴산(polyacrylic acid)이외의 바이오폴리머를 포함한 모래 지반의 흙-습윤 특성곡선이 예측이 가능함을 설명하였다.

• 한국식품영양과학회지
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• 제19권2호
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• pp.133-142
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• 1990

This study was attempted to compare the nutritive value of leaf with stem of the water cress Oenanthe stolonifera DC. in order to improve the eating habits and as a part of studying on the effective curing nutrients for the damaged liver. The contents of moisture crude proteinon the effective curing nutrients for the damaged liver. The contents of moisture crude protein crude fat and crude ash were 90.40% 2.85%, 0.42% and 0.74% in leaf while the contents of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09%, and 0.64% of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09% and 0.64% in stem respectively. The quantitative fractionation of proteini of both leaf and stem ranked albumin the highest content followed globulin prolamin and glutelin in order. It has been sh-own by SDS-polyacrylamide gel electrophoresis that water extractable protein of leaf 11 bands but those of stem were not detected. The scope of molecular weight for the main protein of water extractable protein of leaf was between 34.700 and 45,000. The amounts of extractive-nitrogen from leaf and stem of the water cress were 241.02mg% and 271.67mg% respec-tively. The amounts of free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid composition of both leaf and stem the major components were aspartic acid and glutamic acid. In total amino acid composition of water cress leaf aspartic and glutamic acid were the major components. Whereas alanine and thr-eonine were the major components in stem The assessment of water cress leaf and stem with chemical score. EAAl Rl showed that the values of stem were lower tendancy than those of leaf. Limiting amino acid of leaf was tryptophan while that of stem was lysine.

• 한국식품저장유통학회지
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• 제11권4호
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• pp.530-537
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• 2004

본 연구는 신선편이 양상치를 대상으로 전해수와 유기산의 단독 또는 병용처리에 의한 위해미생물의 살균효과를 조사하였다. 산성전해수는 액상배지에서 L. monocytogenes를 60초 내에 완전히 사멸하였으나, 알칼리전해수는 약 1.7 log CFU/g 정도 감소하였다. 그러나 L. monocytogenes를 접종한 양상치에서 산성전해수는 현저하게 살균력이 감소하여 3분 침지시 약 2.5 CFU/g의 감소를 나타내었으나 알칼리전해수는 산성전해수와 거의 살균력의 차이가 없었다. 한편, L. monocytogenes에 오염된 양상치를 전해수와 유기산 단독 또는 병용처리 하였을 때 무처리구에 비하여 산성전해수와 알칼리전해수는 약 2 log CFU/g 정도의 감소를 나타냈으며, $1\%$ acetic acid, lactic acid, citric acid 및 ascorbic acid를 처리하였을 경우 각각 1.52.5 log CFU/g의 감소를 나타냈으나, 산성전해수와 알칼리전해수에 $1\%$ 유기산을 병용처리 하였을 경우 약 2.63.7 log CFU/g의 현저한 감소를 나타내었다. 특히 산성전해수와 알칼리전해수 모두 $1\%$ citric acid와 병용처리 하였을 때 가장 강한 살균력을 나타내었다. 양상치에 오염된 총균수, 효모 및 곰팡이의 경우도 L. monocytogenes에 오염된 양상치의 살균력과 비슷한 경향을 나타내었다. 또한, L. monocytogenes를 접종한 양상치를 전해수 처리한 후 온도별로 저장하면서 생육변화를 측정한 결과, 병용처리구에서 현저하게 생육이 저해되는 것으로 나타나 양상치를 세척시 알칼리전해수와 $1\%$ citric acid를 병용처리하면 총균수는 물론 L. monocytogenes에 의한 오염방지에 매우 효과적이었다. 한편, SEM 결과, 양상치에 오염된 L. monocytogenes 는 알칼리수와 $1\%$ citric acid의 병용처리구에서는 현저하게 세포막이 파괴되어 세포가 사멸하는 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제6권3호
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• pp.4-9
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• 1976

Free amino acids in water extracts and total amino acids in hydrolystates of Deer Horn were analyzed by amino acid autoanalyzer (Technicon PNC-1 Type). The results obtained from this study are as follows ; 1) 17 kinds of amino acid, including 7 kinds of essential amino acid in human nutrition except tryptophan were identified and quantified. 2) Of all free amino acid contained in water extract, glutamic acid is the richest, and then comes Ala, Gly, Leu, Lys, valin in that order. Of all total amino acid which are closely related with nutritional valuation glycin is the richest, and then comes Glu, Lys, Ala, Leu, Ala, Pro, in that order. 3) Besides 17 kinds of amino acid, one kinds of unknown amino acid are found in water extracts and hydrolysates.

• Korean Membrane Journal
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• 제11권1호
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• pp.21-28
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• 2009

We investigated the effect of organic materials on membrane fouling in advanced drinking water treatment by a hybrid module packed with granular activated carbon (GAC) outside multi-channel ceramic microfiltration membrane. Synthetic water was prepared with humic acid and kaolin to simulate natural water resouces consisting of natural organic matter and inorganic particles. Kaolin concentration was fixed at 30 mg/L and humic acid was changed as 2~10 mg/L to inspect the effect of organic matters. Periodic back-flushing using permeate water was performed for 10 sec per filtration of 10 min. As a result, both resistance of membrane fouling (Rf) and permeate flux (J) were influenced highly by concentration of humic acid. It proved that NOM like humic acid could be an important factor on membrane fouling in drinking water treatment. Turbidity and UV254 absorbance were removed up to above 97.4% and 59.2% respectively.