• Journal of Applied Biological Chemistry
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• 제43권2호
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• pp.86-93
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• 2000

An experiment was conducted to obtain the quantitative data on the transformation and loss of applied urea-N in waterlogged soil columns. The soil columns were pre-incubated for 35 days to develop oxidized and reduced soil conditions prior to urea application. After urea application at the rate of $150kg\;N\;ha^{-1}$(29.5 mg N), the amounts of nitrogen which were volatilized, leached, and remained in soil column were measured during 38 days of incubation period. On 2 and 4 days of incubation, 54.1%(15.9 mg N) and 98.4%(29.0mg N) of the applied urea was hydrolyzed, respectively. Most of the applied urea was completely hydrolyzed within 6 days. After urea application, the rates of ammonia volatilization were increased with the floodwater pH when the floodwater pH were higher than 7.0. The maximum rate of ammonia volatilization was $0.3mg\;d^{-1}$ when pH of the floodwater showed maximum value of 7.6. The total amount of volatilized nitrogen was 6.1% (1.8mg N) of the applied urea-N. A 63.2 % (18.6mg N) of the applied urea was remained in soil as $NH_4{^+}-N$ and 28.0% (8.2mg N) of the applied urea was leached as $NH_4{^+}-N$ at the end of the incubation. Amount of $NO_3{^-}-N$ in soil was smaller than 2.0 mg throughout the incubation period. The total amount of $NO_3{^-}-N$ leached was very small, which value was 1.8 mg. It suggested that nitrification process was not significant in waterlogged soil column of this study due to high infiltration rate of urea solution applied to the soil column. Therefore only small amount of $NO_3{^-}-N$ was lost by denitrification and leaching process.

• 한국토양비료학회지
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• 제30권4호
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• pp.328-333
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• 1997

질소를 함유한 유기인계 살충제로 널리 사용되고 있는 diazinon이 논토양에 살포되었을 때 토양내에서 일어나는 질소대사중 암모니아휘산에 미치는 영향을 조사하고자 질소질비료원의 종류와 diazinon 처리량에 따른 암모니아 휘산의 차이를 조사하였다. 1. 시험토양에 요소, 유안, 유기질비료를 처리후 담수상태가 지속되면서 토양 pH가 약간씩 증가하였으며 토양 pH 증가에 함께 암모니아 휘산량이 증가하는 경향이었다. 2. 질소비료원을 시비하지 않은 시험구에서 diazinon 처리량을 0, 35, 70, 105g a.i./10a로 하였을 때 처리량에 따른 암모니아 휘산량 차이는 인정되지 않았다. 요소, 유안 및 유기질비료원을 시비후 diazinon 처리시 70g a.i/10a에서 가장 많은 암모니아 휘산이 발생하였으나 시간이 경과함에 따라 완만하게 감소하는 경향이었다. 3. 요소비료, 유기질비료 및 유안비료 처리시 질소질비료원의 종류에 따라 암모니아 휘산량이 차이를 보였는데 요소비료는 diazinon 무처리시 약 23%, diazinon 표준처리시 약 42%, 2배처리시 약 66%, 유안비료는 diazinon 처리시 약 3.2%, diazinon 표준처리시 약 4.8%, 2배처리시 약 5.7%, 유기질비료는 diazinon 무처리시 약 1.8%, diazinon 표준처리시 약 8.9%, 2배처리시 약 28.4%의 암모니아 휘산이 발생하였으며 요소비료>유기질비료>유안비료의 순으로 나타났다.

• 한국토양비료학회지
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• 제50권1호
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• pp.49-55
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• 2017

Chinese cabbage cultivation and ammonia volatilization experiments were done to evaluate the efficiency of Agrotain coated urea (GSP 80% + Agro; GSP 100% + Agro) against conventional urea (GSP 80%; GSP 100%). Fresh weight of Chinese cabbage were 17.2% and 7.3% higher in the treatments that received GSP 80% + Agro and GSP 100% + Agro, respectively, of those from the treatments that received urea alone. Likewise, the nitrogen use efficiency of Chinese cabbage in the treatments that received Agrotain coated urea were significantly higher at the rate of 3.5% (GSP 80% + Agro) and 1.9% (GSP 100% + Agro) compared to urea alone treatments. Ammonia emission was substantially higher at the rate of $107.6N\;mg\;chamber^{-1}$ with the application of only GSP 100%. However, nearly 28.3% of ammonia emission was considerably reduced with the use of Agrotain coated urea. Hence, we recommend the use of Agrotain coated urea in conventional farming for increased crop yield as well as simultaneous reduction of nitrogenous fertilizer use.

• 한국작물학회지
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• 제53권1호
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• pp.8-14
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• 2008

Ammonia ($NH_3$) volatilization from a silty clay loam paddy soil applied with non, straight urea, and coated urea, respectively, under transplanting in Milyang, Korea from 2002 and 2003 was simulated by a Water and Nitrogen Management Model (WNMM). Based on the data from the in-situ measurements, $NH_3$ volatilization during the rice growth was 6.04% and 1.46% of the applied nitrogen (N) from straight urea and coated urea, respectively. The bulk aerodynamic approach in WNMM satisfactorily predicted the difference in $NH_3$ loss during the given rice growing seasons from the two urea fertilizers. $R^2$ for the correlation between the predicted and observed NH3 loss during the calibration year (2002) was 0.53 less than 0.68 of the application year (2003). This difference could be due to the weather condition such as heavy rainfall and temperature during the calibration year.

• 한국토양비료학회지
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• 제47권5호
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• pp.368-373
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• 2014

Ammonia loss from urea significantly hinders efficient use of urea in agriculture. The level of nitrous oxide ($N_2O$) a long-lived greenhouse gas in atmosphere has increased mainly due to anthropogenic source, especially application of nitrogen fertilizers. There are reports in the literature showing that the addition of zeolite to N sources can improve the nitrogen use efficiency. This study was conducted to evaluate nitrous oxide ($N_2O$) and ammonia ($NH_3$) emission by mixed treatment of urea and zeolite in upland crop field. Urea fertilizer and zeolite were applied at different rates to study their effect on $N_2O$ emission during red pepper cultivation in upland soils. The $N_2O$ gas was collected by static closed chamber method and measured by gas chromatography. Ammonia concentration was analyzed by closed-dynamic air flow system method. The total $N_2O$ flux increased in proportion to the level of N application. Emission of $N_2O$ from the field increased from the plots applied with urea-zeolite mixture compared to urea alone. But urea-zeolite mixture treatment reduced about 30% of $NH_3$-N volatilization amounts. These results showed that the application of urea and zeolite mixture had a positive influence on reduction of $NH_3$ volatilization, but led to the increase in $N_2O$ emission in upland soils.

• 한국토양비료학회지
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• 제50권5호
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• pp.325-335
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• 2017

This study was carried out for 30 days in aeration type and agitation type reactor to characterize organic matter decomposition and ammonia volatilization during the liquid composting of pig slurry, and organic matter and nitrogen removal rate through mass balance analysis was analyzed. In the aeration type reactor, the pH increased from 7.0 to 9.13, and TS 34.5%, VS 33.4%, $BOD_5$ 71.2%, $COD_{Cr}$ 62.3% and TOC 83.2% were removed. In addition, 44.6% of TN and 65.0% of ${NH_4}^+-N$ were removed. In the agitation type reactor, the pH increased from 7.0 to 8.10, and the removal rates of TS 0.9%, VS 0.5%, $COD_{Cr}$ 27.5%, $BOD_5$ 28.9% and TOC 41.3% were obtained. And TN and ${NH_4}^+-N$ showed removal rate of 25.3% and 29.2%, respectively. The first order kinetics constant related to $BOD_5$ degradation was $-0.039day^{-1}$ for aerobic liquid composting and $-0.013day^{-1}$ for agitated reactor. Nitrogen loss in aerobic liquid composting was about 2.3 times higher than that of agitated reactor, whereas FAN/TAN in aerobic liquid composting was about 7.9 times higher than that of agitation type reactor. Therefore, despite the low FAN/TAN in the agitation type reactor, the nitrogen loss rate was relatively high.

• 한국산업보건학회지
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• 제1권2호
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• pp.200-213
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• 1991

ln order to acquire the fundamental data for the organic solvents in bond and to contribute the health improvement of workers in deprtment of organic solvents in shoes manufacturing industries. The authors surveyed the contents of organic solvent in adhesive and determined the amount of volatilization of organic solvent by time and temperature with gaschromatography from March to September 1990. The results were as follows; 1) The kinds for organic solvents in bond were 9 that was Toluene, C-Hexane, N-Hexane, C-Hexanon, Aceton, Methyl Ethyl Keton, Dimethyl Formamide, Etyly Acetate. 2) Toluene and Methyl Ethyl Keton among the organic solvents in adhesive were over 80.18%. 3) The amount of volatilization of Methyl Cyclohexanone and Aceton by time and temperature were the most level than other compounds.

• 한국환경보건학회지
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• 제32권5호
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• pp.499-505
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• 2006

Bioventing efficiency was compared in a continuous and an intermittent(6hr injection and 6hr rest) air injection mode. Two lab-scale columns which packed with 5 kg of soil artificially contaminated by diesel oil were operated. The columns were maintained at the $25^{\circ}C{\pm}2.5$ in order to minimize the effect of exterior temperature variation. The flow rate of air injection mode were maintained constantly at the flow rate of 10 ml/min. The moisture of the columns was stably maintained at $60{\sim}80%$ of field capacity. The nutrient compounds were added to make C:N:P ratio as 100:10:l. The continuous and intermittent injection modes showed 67.56% and 69.63% reduction of initial TPH concentration during 90 days, respectively. Two venting modes showed similar results in the analysis of the trends of the hydrocarbon utilizing bacterial counts for operating periods. The carbon dioxide production rate of the continuous injection mode was higher than that of intermittent injection mode. The loss of diesel oil by volatilization in the continuous and intermittent injection modes were about 5% and 1%, respectively. The lower volatilization loss in the intermittent injection mode suggested that the biodegradation of TPH in the intermittent injection mode was greater than that of the continuous mode. These results suggested that the intermittent injection mode is more efficient than the continuous venting mode.

• 한국토양비료학회지
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• 제14권1호
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• pp.24-30
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• 1981

가리(加里)의 시용(施用)과 이의 벼뿌리에 의한 흡수(吸收)가 암모니아의 휘산(揮散)과 벼의 질소흡수(窒素吸收)에 미치는 관계(關係)를 알고자 Pot 시험과 포장시험(圃場試驗)을 동시(同時)에 수행(遂行)하여 얻어진 결과(結果)는 다음과 같다. 1. 벼가 재배(栽培)되는 가리시용구(加里施用區)에서는 요소(尿素)의 시용(施用)으로 암모니아의 휘산(揮散)이 일시(一時) 증가(增加)하였으나 점차(漸次) 감소(減少)하여 무가리구(無加里區)에서 보다도 적은 수준(水準)으로 떨어졌다. 2. 벼에 의(依)한 질소(窒素)의 총흡수량(總吸收量)이 무가리구(無加里區)에서 보다 가리구(加里區)에서 현저(顯著)히 많았고 마침내는 습토(濕土)의 pH가 무가리구(無加里區)에서 보다 가리구(加里區)에서 낮아졌다. 3. 질소(窒素)의 시용(施用)으로 가리구(加里區) 토양(土壤)의 pH가 일시(一時) 무가리구(無加里區)보다 높아져서 암모니아의 휘산(揮散)이 느렸으나 바로 벼의 생육량(生育量)과 질소(窒素)의 흡수량(吸收量)이 늘어서 암모니아의 휘산량(揮散量)이 무가리구(無加里區)에서 보다 줄고 토양(土壤)의 pH도 낮아진 것으로 나타났다. 4. 벼뿌리가 차단(遮斷)된 조건하(條件下)에 요소(尿素)가 시용(施用)되었을 때는 무가리구(無加里區)에서 보다 가리구(加里區)에 습토(濕土)의 pH가 낮으며 암모니아의 휘산량(揮散量)도 적어졌다. 5. pH가 높은 토양(土壤)에서는 가리(加里)의 기비다용(基肥多用)이 벼의 생육초기(生育初期)에 암모니아의 휘산(揮散)을 경감(輕減)하고, pH가 높지 않은 보통토양(普通土壤)에서는 가리(加里)의 기비(基肥) 다용(多用)이 습토(濕土)의 pH를 높이어 이질후(移秩後) 벼의 생육초기(生育初期)에 암모니아의 휘산(揮散)을 높일 염려(念慮)가 있는 것으로 생각된다.

• 한국토양비료학회지
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• 제38권3호
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• pp.157-163
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• 2005

최근 지구온난화에 따른 농업환경이 변화와 기상변화에 대비한 작물의 영양관리 대책 도출과 지속적인 농업생산체계를 확보 하고자 논토양에서 완효성 비료시용시 질소이용률 평가와 질소수지를 분석하였다. NPK 처리구의 표층수중 $NH_4-N$ 농도는 벼 이앙초기 $2.07mg\;L^{-1}$이었으나 그 이후 감소하다가 수비시용과 더불어 $NH_4-N$ 농도가 증가하였다. 완효성 시비구의 $NH_4-N$ 농도는 벼 이앙 18일 이후부터는 NPK 시용구보다 높았다. NPK 시용구의 $NO_3-N$ 함량 변화는 벼 이앙 10일경에 약 $3.97mg\;L^{-1}$로 가장 높았으며 그 이후는 감소하였다. CRF100% 시용구의 $NO_3-N$ 함량 변화는 벼 이앙 후 30일까지 $3-5mg\;L^{-1}$ 범위를 보이다가 그 이후는 감소하는 경향이었다. 토양중 $NH_4-N$ 함량 변화는 NPK 처리구에서 이앙 초 $120mg\;kg^{-1}$ 내외였으며, 이앙 20일 이후에 $45mg\;kg^{-1}$으로 감소하였다가 추비로 인하여 $NH_4-N$ 함량이 다시 $45mg\;kg^{-1}$로 증가하였다. 완효성비료 시용구에서는 벼 생육초기에는 처리 간 차이가 없었으나 이앙 25일 이후부터 NPK 시용구에 비하여 완효성비료 시용구에서 $NH_4-N$ 함량이 증가하였다. NPK 처리구에서 암모니아 휘산으로 손실된 질소량은 $22.4kg\;ha^{-1}$이었며, 완효성 비료를 시용함으로서 67%까지 암모니아 휘산을 줄일 수 있었다. 질소 이용율은 NPK 시용구가 27.4%이었고, CRF70% 시용구는 51.2%, CRF100% 시용구는 49.0%였다. 또한 질소 흡수량은 전반적으로 질소수준이 높을수록 흡수량이 많았다. 수량은 NPK 시용구가 $4,510kg\;ha^{-1}$이었고, CRF70% 시용구는 $4,800kg\;ha^{-1}$, CRF100% 시용구는 $4,970kg\;ha^{-1}$이였다.