• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 Proceedings of 2000 KSAM International Symposium and Spring Meeting
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• pp.100-107
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• 2000

In a recently developed strategy for in-situ treatment of polychlorinated biphenyls (PCB), bioaugmentation was used in conjunction with a surfactant, sorbitan trioleate, as a carbon source for the degrader bacteria, along with the monoterpene, carvone, and salicylic acid as inducing substrates. Two bacteria were used for soil inoculants, including Arthrobacter sp. st. B1B and Ralstonia eutrophus H850. This methodology achieved 60% degradation of PCBs in Aroclor 1242 after 18 weeks in soils receiving 34 repeated applications of the degrader bacteria. However, an obvious limitation was the requirement for soil mixing after every soil inoculation. In the research reported here, bioaugmentation and biostimulation treatment strategies were modified by using the earthworm, Pheretima hawayana, as a vector for dispersal and mixing of surface-applied PCB-degrading bacteria and soil chemical amendments. Changes in microbial biomass and microbial community structure due to earthworm effects were examined using DNA extraction and PCR-DGGE of 16S rDNA. Results showed that earthworms effectively promoted biodegradation of PCBs in bioaugmented soils to the same extent previously achieved using physical soil mixing, and had a lesser, but significant effect in promoting PCB biodegradation in biostimulated soils treated with carvone and salicylic acid. The effects of earthworms were speculated to involve many interacting factors including increased bacterial transport to lower soil depths, improved soil aeration, and enhanced microbial activity and diversity.

• 한국자원식물학회지
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• 제35권6호
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• pp.762-769
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• 2022

Growth characters and ingredient contents of two-year-old bellflower (Platycodon grandiflorum) roots were investigated under both control and soil moisture treatment condition using soil moisture control system including soil sensing and automatic water supply chain in this study. Root diameter, fine root number, root length, fresh weight and dry weight of the plant were significantly influenced by the automatic water treatment, 20%, 30%, 40% and 50%, respectively. Ingredient contents of the two-year-old roots in bellflower plants were detected in the 20% and 50% of controlled soil moisture content. Contents of amino acids were decreased by the soil moisture treatment, meanwhile, contents of minerals were not showed significant decrease except for phosphorus content. Showing no difference in proline and tyrosine, fourteen of the amino acid contents were gradually decreased by the increased soil moisture contents, with significant decrease in serine, glycine, alanine, leucine, lysine and histidine at 20% treatment.

• Applied Biological Chemistry
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• 제31권1호
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• pp.79-85
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• 1988

제초제(除草劑)가 토양환경내(土壤環境內)의 생화학적(生化學的) 전환과정(轉換過程)에 미치는 영향(影響)을 규명(糾明)하기 위해서 화학구조(化學構造)가 다른 여러 종류의 제초제(除草劑)를 질소질비료(室素質肥料)인 요소(尿素)와 함께 토양(土壤)에 처리(處理)하였을때 토양효소(土壞酵素)의 활성(活性)에 미치는 영향(影響)과 농약(農藥)의 잔류량(殘留量)의 변화(變化)를 조사(調査)한 결과(結果)는 다음과 같았다. 제초제(除草劑)의 처리(處理)로 Urease의 활성(活性)에는 Urea계(系), dinoseb, propanil, diphenylether계(系), 산amide계(系)의 순(順)으로 저해율(沮害率)이 높았다. L-Glutaminase 및 protease의 활성(活性)에는 dinoseb, urea계(系), diphenylether계(系), 산amide계(系)의 순(順)으로 저해율(沮害率)이 높았으며 phosphatase는 dinoseb, diphenylether계(系), urea계(系), 산amide계(系)의 순(順)으로 저해율(沮書率)이 높았다. 대체적으로 제초제(除草劑)의 처리(處理)로 처리초기(處理初期)에는 저해(沮害)를 보이다가 28일(日) 이후(以後)에는 거의 영향(影響)이 없거나 활성(活性)을 약간 증가(增加)시켰다. 요소(尿素)의 시용(施用)으로 인(因)해 제초제(除草劑)의 분해(分解)는 무시용구(無施用區)에 비해서 약간 촉진(促進)되었다.

• 한국토양비료학회지
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• 제49권6호
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• pp.651-654
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• 2016

A number of accidents relating to highly toxic hydrogen fluoride (HF) or hydrofluoric acid (HA) release have occurred over fast few decades in Korea. Thus, this study was conducted to investigate the fluoride (F) concentrations in paddy soil and brown rice from 2 different areas where the soils were exposed to HF and HA. In the first case, the HF leakage accident that occurred in 2012 affected the surrounding soils and crops and consequently, crops (rice) affected by HF were unavailable for forage even though F did not accumulate in the soil. For example, at the time of accident, F concentrations in brown rice samples were $33.0-1,395mg\;kg^{-1}$, while F concentrations in soil samples were $155-295mg\;kg^{-1}$ which were less than the Korean standard guideline values of $400mg\;kg^{-1}$. However, after a year, F concentrations in brown rice were observed below the detection limit ($1mg\;kg^{-1}$), although F concentrations in soils were similar with those in 2012. Also, large amounts of wastewater discharges containing HA occurred in 2013 and some agricultural soils exceeded the Korean standard guideline values for F ($400mg\;kg^{-1}$), but soil-plant F transfer was not observed. In conclusion, it was observed that soil to plant transfer of F is unlikely although HF and HA as gas or liquid form can cause direct damage to plants.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권6호
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• pp.73-81
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• 2018

Inductively coupled plasma-mass spectrometry (ICP-MS), one of the most commonly used instruments for metal analysis, was used to determine total uranium in soil. The method was named as "Modified ASTM C1345-96". When comparing with ASTM C1345-96, digestion time (2~3 days) was shorten to 7 hours and the treatment in furnace was eliminated. In analyses of 26 field soil samples, there was a significant difference in the average concentration of total uranium between modified ASTM C1345-96 and ASTM C1345-96 (F : 6.22 > Fc : 4.03, significance level : 0.05, n=26). The average concentration of modified ASTM C1345-96 was 1.8 times larger than that of ASTM C1345-96. In addition, modified ASTM C1345-96 was compared with other acid digestion methods for soil including ISO 11466, Modified ISO 11466, US EPA-3051, US EPA-3051A and US EPA-3052 using a certificated reference material (SRM 2711a, NIST) and field soil samples with different level of organic matter content (1.6%, 5.8%, 10.6%). Modified ASTM C1345-96 showed the best accuracy of 93.01% for SRM 2711a. Also, modified ASTM C1345-96 showed the higher extraction rates than other digestion methods by 11~45%.

• 한국지하수토양환경학회지:지하수토양환경
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• 제9권4호
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• pp.8-14
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• 2004

카드뮴과 크롬으로 오염된 토양에 EDTA 와 붕산 혼합용출제를 주입하는 토양수세법(Soil flushing)을 적용 시 최적운전조건을 결정하기 위해서 여러 가지 반응조건에서 카드뮴과 크롬의 제거효율을 측정하였다. 카드뮴의 제거효율은 EDTA 농도가 0.001M에서 0.1M로 증가하면서 $73.2\%$에서 $98.5\%$로 $25.3\%$증가하였으며, 크롬의 제거효율은 붕산의 농도가 0.001M에서 0.1M로 증가하면서 $59.2\%$에서 $100\%$로 $40.8\%$가 증가하였다. 서로 다른 특성을 갖고 있는 카드뮴과 크롬 오염토양에 pH가 3,5,7로 조정된 0.005M EDTA 와 0.005M 붕산 혼합용출제를 주입하여 제거효율을 측정한 결과 카드뮴의 제거효율은 pH가 3에서 7로 증가함에 따라 $92.4\%$에서 $80.9\%$로 감소하였으며, 크롬의 제거효율은 pH 5에서 $70.4\%$로 가장 높았다. pH 5에서 EDTA&붕산 혼합용출제의 농도비를 변화시키면서 카드뮴의 제거효율을 측정한 결과 [EDTA]:[붕산]=0.01M:0.1M에서 가장 효율적이며, 크롬의 제거효율은 [붕산] 주입농도가 0.1M이상일 때 가장 효율적인 것으로 조사되었다. 광산지역과 산업지역에서 채취한 실제오염토양에 적용한 실험에서도 비슷한 결과를 얻었다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권4호
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• pp.434-440
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• 1998

Seven hybrid lines of Leucaena leucocephala $\times$ L. diversifolia and two control lines of L. leucocephala were compared for their adaptation to acid-soils and tolerance to damage by the psyllid, Heteropsyla cubana, at four locations over two years in Peninsular Malaysia. Primary data on leaf composition and in vitro digestibility (nutrition variables) and secondary data on plant height, stem girth and psyllid damage (agronomy variables) were the measures of performance. Cluster solutions of the nine lines were different within locations, between locations and between years for nutrition and agronomy variables. Controls and hybrids did not cluster separately. Principal component scores of the nine lines gave rank orders which were different by location and by year. No performance trend could be detected between hybrids and controls. The conclusion is that nutritional and agronomic characteristics in Leucaena are independent, soil composition and weather did not consistently affect performance, and evidence is inconclusive as to the benefits of interspecific crossing with L. diversifolia.

• 대한화학회지
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• 제13권1호
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• pp.62-67
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• 1969

The adaptabilities of various nitrohumates (-K, -Na and $-NH_4$ salt) as a soil conditioner and a raw material for soluble phosphatic fertilizer were studied. 1. Nitrohumates (especially $-NH_4$ salt) protect the soil from fissures and control the phosphoric acid adsorptive functions of soils considerably. 2. Most effective nitrohumic acids as a soil conditioner were prepared with 15% $HNO_3$ solution composed of five times of original humic acids (by weight) at $80^{\circ}C$ for 2 hrs under continuous stirring. 3. When 50% (by weight) of $NH_4$-nitrohumate were added to apatites in water and boiled for 2 hrs, maximum 26% of $P_2O_5$(apatite contains 37% of $P_2O_5$) were changed into water soluble forms.

• 한국환경생태학회지
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• 제7권1호
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• pp.10-21
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• 1993

소나무, 곰솔, 젓나무 및 독일가문비를 대상으로 인위적으로 산도를 조절한 인공산성우(PH 3.0, 4.0 및 5.0)와 지하수(pH 6.5)를 1991년 4월부터 1993년 8월까지, 생육기간 중에는 주 2~3회, 겨울철은 주 1회 1회 5mm의 강도로 처리하였다. 인공산성우를 처리하면서 수종별 발아 및 득묘율, 토양산도, 유묘의 생장 및 접촉각(contact angle)을 조사.비교하여 얻은 결과는 다음과 같다. 묘목의 생장관련 형질(묘고, 지하부, 엽량 및 개체당 건중량)의 경우에는 산성우처리 초기에는 산성우 처리가 양료로서의 효과를 가지는 것으로 판단되며, 수종별로 상이한 반응을 보였다. 그러나 처리가 2년 이상 지속된 3차년도에서는 처리산성우의 산도수준이 높을수록 모든 수종에서 생장관련 형질들이 감소되는 경향을 보였으며, 이는 토양완충력의 한계 이상으로 투하되는 산집적에 의한 결과로 판단된다. 엽피해율이나 엽량(낙엽율)등의 자료는 처리산성우의 산도수준과 관련지어져 있는 것으로 나타나 산성우 피해의 조기판단 기준으로 사용가치가 높을 것으로 판단된다. 토양산도는 처리간 고도의 통계적 유의차가 인정되었다. 침엽의 표면과 물방울이 이루는 접촉각을 측정한 결과, 처리산성우의 산도수준이 높을수록 엽령이 높을수록 접촉각의 크기는 낮아졌다. 접촉각을 측정비교하는 방법은 야외에서 침엽수류에 대한 산성우 피해의 조기판단을 위한 알맞고 훌륭한 기준이라 판단된다.

• 한국지반환경공학회 논문집
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• 제14권8호
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• pp.5-9
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• 2013

본 연구에서는 저에너지, 친환경적인 방법의 지반개량을 목적으로 하는 유기산재의 지반개량재로서의 강도특성을 모색하였다. 이에 유기산재를 활용하여 재령 28일까지의 일축압축강도시험 및 삼축압축시험을 통한 흙의 강도 변화에 대해 분석하였다. 유기산 재료를 첨가한 점토의 강도는 재령이 길어질수록, 유기산재 혼합비가 커질수록 전반적으로 증가하는 경향을 나타내었다. 유기산계 지반개량재 혼합에 따른 점토의 강도 증진 효과를 파악하는데 있어서, 일축압축강도시험과 삼축압축시험 결과를 통해 유기산재가 지반개량재로 쓰였을 때 가져오는 강도 증대효과가 있다는 것을 알 수 있었다. 결과적으로, 실내시험을 통해 지반개량에 있어 유기산계 지반개량재의 활용가능성을 볼 수 있었다. 향후 세부적인 시험과 현장시험이 좀 더 명확한 강도증진을 규명하는데 도움이 될 것으로 판단된다.