• 한국환경농학회지
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• 제33권1호
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• pp.1-8
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• 2014

BACKGROUND: Recent studies using many amendments for heavy metal stabilization in soil were conducted in order to find out new materials. But, the studies accounting for the use of appropriate amendments considering soil pH remain incomplete. The aim of this study was to investigate the effects of initial soil pH on the efficiency of various amendments. METHODS AND RESULTS: Acid soil and alkali soil contaminated with heavy metals were collected from the agricultural soils affected by the abandoned mine sites nearby. Three different types of amendments were selected with hypothesis being different in stabilization mechanisms; organic matter, lime stone and iron, and added with different combination. For determining the changes in the extractable heavy metals, water soluble, Mehlich-3, Toxicity Characteristic Leaching Procedure, Simple Bioavailability Extraction Test method were applied as chemical assessments for metal stabilization. For biological assessments, soil respiration and root elongation of bok choy (Brassica campestris ssp. Chinensis Jusl.) were determined. CONCLUSION: It was revealed that lime stone reduced heavy metal mobility in acid soil by increasing soil pH and iron was good at stabilizing heavy metals by supplying adsorption sites in alkali soil. Organic matter was a good source in terms of supplying nutrients, but it was concerning when accounting for increasing metal availability.

• 한국의류학회지
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• 제1권1호
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• pp.31-37
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• 1977

The effects of surfactants and concentration of NaOH in surfactant solution on the removal of free fatty acid soil from cotton fabrics were investigated. Cotton fabrics were soiled with palm itic acid which is the most common fatty acid found in natural oily soil and washed in Lauder-ometer with various types of surfactant with or without NaOH. The rate of soil removal was estimated by analyzing palmitic acid contents in fabric before ar d after washing. Analysis of palmitic contents was made by extracting palmitic acid with azeotropic mixture of alcohol-benzene and the extracts were titrated with standard NaOH solution. It was shown that the types of surfactant are important factor in free fatty acid removal and the efficiency increases in the following order: SLS$90\%$ of initial sorption. In relation to the mechanism of detergency, the suspending and emulsifying power of surfactants were also examined. From the results of this experiments, it could be concluded that the soap formation with alkali and the suspending power of surfactant arc significant factors in free fatty acid soil removal, but the emulsifying power of it is neglizible.

• 한국의류학회지
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• 제5권1호
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• pp.15-21
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• 1981

The effect of fatty acid content in oily soil and conditions of washing on the removal of triglyceride have been studied. Cotton lawn was soiled with the four-component soil-tripalmitin, palmitic acid, dodecyl alcohol and dodecane-and washed in constant temperature waterbath shaker. The detergency was estimated by analysis of triglyceride labelled carbon-14 on fabrics before and after washing by means of liquid scintillation counting. It was shown that the detergency of triglyceride washed with the nonionic, nonylphenol poly (10)-ethylene oxide and soap was increased steadily with increasing temperature, whereas with the anionics Na-DBS and SLS, the detergency was rather decreased when the temperature was elevated above $40^{\circ}C$. To investigate the effects of free fatty acid content in soil on the removal of triglyceride, the fabrics were soiled altering palmitic acid content, and then washed. From the results, the detergency of triglyceride was developed with increasing free fatty acid content. With soils containing less than $30\%$ of free fatty acid, of the three detergents tested, the nonionic was by far the most effective soil removal. Soap was intermediate and the synthetic anionic was the poorest. With soil containing $45\%$ of free fatty acid, soap was the most effective soil removal. When NaOH was added to detergent solution. the detergency of triglyceride was improved without regard to detergents. The optimum alkalinity was obtained according to free fatty acid content. And the alkalinity changed to low NaOH concentration with increasing free fatty acid content. From the results mentioned above, it could be concluded that the major removal mechanisms of triglyceride containing oily soil were mesomorphic phase formation, solubilization and soap forma-tion when alkali was added in detergent solution.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.242-246
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• 2005

The heavy metal analysis (Cd, Pb, Cu, Cr, Zn, Ni) with various extraction methods was performed using the certified sample and real soil sample. In case of the certified samples, $10.5{\sim}118%$ of recovery was showed with various ranges depend on the metal kinds and extraction methods. Also, the alkali-digestion method was showed the proper results by applying in hexavalent chromium. In case of real sample, compared to amounts of heavy metals extracted using 0.1N-HCl, those extracted using acid digestion are higher by $3{\sim}24$ times in Cu, $1.1{\sim}1.5$ times in Cd, $2{\sim}23$ times in Pb, $3{\sim}104$ times in Zn, $12{\sim}101$ times in Ni, $30{\sim}202$ times in Cr. There is no considerable difference between four acid digestion methods.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.220-223
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• 2006

To investigate the effect of solution pH and particle size of Na-bentonite on swelling characteristics and relative hydraulic conductivity, four kinds of acids and two alkali were selected. The results showed that the swelling was decreased to half of the original Na-bentonite's swelling index. Also the decrease in SI was most distinctive in pH 3.5 of HCl. But changes of swelling index between initial and stabilized were minimal in alkali treatment, compared to the change by acid treatment. No flux was detected under atmospheric pressure although there was drastic decrease in swelling. However, leaching started after application of 1.5 bars of air-pressure equivalent to 15 m of water head.

• 한국식품과학회지
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• 제23권2호
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• pp.161-166
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• 1991

미생물을 이용한 유용물질 생산연구의 일환으로 토양으로부터 생물고분자 생산균주를 분리하고, 이 분리균에 대한 균학적 성질 및 생성 생물고분자의 이화학적 성상을 검토하였다. 분리균주는 Bacillus속의 한 균종으로 동정 하였으며, 알칼리 내성균주의 특징을 나타내었다. 이 균주로부터 생성된 생물고분자는 성분분석, 정색반응 및 I.R. spectrum 분석결과 단백질 함량이 높고, 일부 amino sugar가 존재하나 uronic acid는 함유하지 않았다. 그러나 cetyl pyridinium chloride에는 침전되어 산성의 생물고분자인 것으로 추정되었다.

• The Korean Journal of Ecology
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• 제13권2호
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• pp.131-142
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• 1990

From July 1, 1985 to June 30, pH values of precipitation in Seoul area were average 5.1 and acid rain which was lower than pH 5.5 showed a frequence of 70.7%. Seasonal changes appeared in pH values of annual precipitation in Seoul. The pH patterns of spring and autumn were generally less acid than that of summer and winter, and snowfall pH was lower than rainfall. The beginning rainfall in Seoul was neutral because of alkali dust in the atmosphere. As times went on, rainfall pH was gradually low and after 1 to 2 hours, showed a steady state. On the surface soil precipitation was neutralized by soil buffering capacity.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(2)
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• pp.439-444
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• 1997

In order to investigate organic association of fallout cesium, strontium and plutonium in the soil, soil samples influenced by fallout from nuclear weapon testings were treated with alkali (0.1 M-sodium hydroxide solution) to extract organic acids. After extraction, the resultant three fractions (sedimentary residue, humic and fulvic acid fractions) were subjected to the r-ray spectrometric analysis for $^{137}$ Cs, and radiochemical analysis for gosr and $^{239,240}$Pu. Alkali extraction experiments showed that a lot of $^{ 239,240}$Pu was extracted to organic acids from the soil samples, whereas most of $^{137}$ Cs and $^{90}$ Sr remained in residual fraction. Less than 10% of the total $^{137}$ Cs and $^{90}$ Sr was found in the organic fraction. The concentrations of $^{137}$ Cs and $^{90}$ Sr associated with humic fractions were higher than those with the corresponding fulvic fractions. It was found that more than 40% of the total $^{239,240}$Pu was associated with the organic fraction of soils. In contrast with $^{137}$ Cs and $^{90}$ Sr, $^{239,240}$Pu associated with vulvic fractions was much higher than in humic fractions.

• 한국환경농학회지
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• 제33권2호
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• pp.78-85
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• 2014

BACKGROUND: Recent studies using various industrial wastes for heavy metal stabilization in soil were conducted in order to find out new alternative amendments. The acid mine drainage sludge(AMDS) contains lots of metal oxides(hydroxides) that may be useful for heavy metal stabilization not only waste water treatment but also soil remediation. The aim of this study was to investigate the applicability of acid mine drainage sludge for heavy metals stabilization in soils METHODS AND RESULTS: Alkali soil contaminated with heavy metals was collected from the agricultural soils affected by the abandoned mine sites nearby. Three different amounts(1%, 3%, 5%) of AMDS were applied into control soil and contaminated soil. For determining the changes in the extractable heavy metals, $CaCl_2$ and Mehlich-3 were applied as chemical assessments for metal stabilization. For biological assessments, lettuce(Lactuca sativa L.) and chinese cabbage(Brassica rapa var. glabra) were cultivated and accumulation of heavy metals on each plant were determined. It was revealed that AMDS reduced heavy metal mobility and bioavailability in soil, which resulted in the decreases in the accumulation of As, Cd, Cu, Pb, and Zn in each plant. CONCLUSION: Though the high level of heavy metal concentrations in AMDS, any considerable increase in the heavy metal availability was not observed with control and contaminated soil. In conclusion, these results indicated that AMDS could be applied to heavy metal contaminated soil as an alternative amendments for reducing heavy metal mobility and bioavailability.

• Applied Biological Chemistry
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• 제21권2호
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• pp.71-80
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• 1978

불란서(佛蘭西)의 수종(數種) 토양중(土壤中)에서 3,4-DCA 및 TCAB의 변화과정을 구명하기 위하여 환표식(環標識)된 $^{14}C-3,4-DCA$ 및 $^{14}C-TCAB$를 사용하여 실험을 행(行)한 바 다음의 결과(結果)를 얻었다. (1) $^{14}C-3,4-DCA$가 $^{14}CO_2$로 분해(分解)되는 속도(速度)는 배양초기(培養初期)에는 비교적(比較的) 빠르고 후기(後期)에는 완만하다. 배양 6개월 후(後)에 alkaline soil(pH=7.9)에서 dose 1(1.5 ppm)에서 최고(最高) 6.5%, dose 2(94 ppm)에서 최하(最下) 1.92%의 분해율(分解率)을 보였다. organic acid soil(pH=5.5)의 경우 dose 1에서 4.91%, dose 2에서 4.24%가 분해(分解)되었으며 양자간(兩者間)에는 대차(大差)가 없었다. (2) Dose 1로 3,4-DCA를 6개월동안 배양할 때 organic acid soil에서는 47.70%, Alkaline soil에서는 29.49%가 토양에 결합되었다. 한편 dose 2의 경우 organic acid soil에서는 38.40%, alkaline soil에서는 20.30%가 결합(結合)되었다. (3) 토양중(土壤中)에서 3,4-DCA로부터 생성(生成)되는 TC-AB의 양(量)은 토양(土壤)의 종류(種類)보다는 3,4-DCA의 사용농도(使用濃度)에 의존(依存)하는것 같다. dose 2에서 생성(生成)된 TCAB의 양(量)은 organic acid soil에서는 추출액(抽出液)의 총방사능(總放射能)의 50%, alkaline soil에서는 30%에 해당하며 이것은 토양시료(土壤試料)에 첨가한 최초(最初)의 방사능(放射能)의 1.8%와 1.4%에 각각(各各) 해당된다. 반면 dose 1에서는 추출액(抽出液)의 총방사능(總放射能)에 비(比)하여 두 토양(土壤) 공(共)히 $2{\sim}3%$를 넘지 못하며 최초(最初)의 총방사능(總放射能)의 $0.05{\sim}0.1%$를 초과(超過)하지 못한다. (4) $^{14}C-TCAB$가 $^{14}CO_2$로 분해(分解)되는 속도(速度)는 매우 느리며 배양 6개월후에 4종(四種)의 토양(土壤)에서 모두 $0.05%{\sim}0.20%$의 분해율(分解率)을 보였고 배양 3개월후에 뚜렷한 분해산물(分解産物)을 검출(檢出)할 수 없었으며 대부분(大部分) 미분해(未分解)된 상태로 존재(存在)하였다. (5) Alkaline soil에서 다른 토양에서 보다 훨씬 많은 양(量)의 $^{14}C-TCAB$가 토양중(土壤中)에 흡착(吸着)된 것으로 보아 Alkali토양 조건하에서 $trans-TCAB{\rightarrow}cis-TCAB$의 전환(轉換)이 일어나 이 흡착성이 더 강한 cis 이성체(異性體)가 토양중(土壤中)에 많이 흡착(吸着)된 것으로 생각(生覺)된다.