• 상하수도학회지
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• 제35권2호
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• pp.135-142
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• 2021

The activity of anaerobic ammonium oxidation (ANAMMOX) immobilized in synthetic media (Poly Ethylene Glycol, PEG) and granular form was evaluated comparatively to investigate the effect of influent nitrogen concentration and exposure of oxygen. In ANAMMOX granule reactor, when concentration of influent total nitrogen increased to 500mg/L, removal efficiency of ammonium, nitrite and nitrate were shown to 90.5±6.5, 96.6±4.9, and 93.2±6.1%, respectively. In the case of the PEG gel, it showed lower nitrogen removal performance, resulting in that the removal efficiency of ammonium, nitrite and nitrate were shown to 83.3±13.0, 96.4±6.1, and 90.3±7.5%, respectively. In second step, when exposed to oxygen, the nitrogen removal performance in the ANAMMOX granule reactor also remained stable, but the activity of PEG gel ANAMMOX was found to be inhibited. Consequently, the PEG gel ANAMMOX was a higher sensitivity than that of granular ANAMMOX with two variables applied in this study.

• 한국환경과학회지
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• 제20권1호
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• pp.119-126
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• 2011

In this study, reaction model and reactions rate accelerated by o-iodosobenzoate ion(IB$^{\ominus}$) on hydrolysis reaction of p-nitrophenyl valate(NPV) using ethyl tri-octyl ammonium mesylate(ETAMs) for quaternary ammonium salts, the phase transfer catalysis(PTC) reagent, were investigated. The effect of IB$^{\ominus}$ on hydrolysis reaction rate constant of NPV was weak without ETAMs solutions. Otherwise, in ETAMs solutions, the hydrolysis reactions exhibit higher first order kinetics with respect to the nucleophile, IB$^{\ominus}$, and ETAMs, suggesting that reactions are occurring in small aggregates of the three species including the substrate(NPV), whereas the reaction of NPV with OH$^{\ominus}$ is not catalyzed by ETAMs. Different concentrations of NPV were tested to measure the change of rate constants to investigate the effect of NPV as substrate and the results showed that the effect was weak. This means the reaction would be the first order kinetics with respect to the nucleophile. This behavior for the drastic rate-enhancement of the hydrolysis is referred as 'Aggregation complex model' for reaction of hydrophobic organic ester with o-iodosobenzoate ion(IB$^{\ominus}$) in hydrophobic quarternary ammonium salt(ETAMs) solutions.

• Journal of Microbiology and Biotechnology
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• 제5권3호
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• pp.158-162
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• 1995

The effect of carbon and nitrogen sources on the production of novel aminopeptidase M inhibitors MR-387A and B by Streptomyces sp. SL-387 has been studied. High D-glucose and ammonia concentrations (5$\%$ and 1$\%$, respectively) exerted a negative influence on the inhibitor formation. The suppressive effect of glucose on the inhibitor formation is probably caused by an effect of medium pH rather than that of cyclic AMP. To establish the optimum conditions for inhibitor overproduction, various nitrogen sources and ammonium ion-trapping agents were examined. The use of ammonia slow-releasing nitrogen sources such as soybean meal and fish meal, or ammonium ion-trapping agents such as kaoline, celite, and natural zeolite achieved the enhancement of inhibitor production. These results also indicate that inhibitor formation is affected by ammonium ion repression.

• Journal of Applied Biological Chemistry
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• 제49권1호
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• pp.28-32
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• 2006

Effect of organic-C on immobilization and nitrification patterns in acidic soil was examined during 20 weeks incubation period to verify if organic amendments such as composted material can increase soil retention of N by stimulating microbial immobilization of $NH_4^+$. Four treatments were laid out: control without fertilizer N and glucose (treatment code: S), ammonium sulfate (SN), ammonium sulfate with single glucose at the commencement (0 week) of incubation (SNG), and ammonium sulfate with double glucose at 0 and 4 weeks of incubation (SNGG). Glucose application (SNG) significantly increased microbial immobilization of $NH_4^+$ within 1 week of incubation over SN. Immobilization was followed by remineralization thereafter; however, second-application of glucose (SNGG) restored $NH_4^+$ immobilization. At the same time, nitrification was significantly inhibited by glucose application as indicated by consistently low $NO_3^-$ concentration in SNG and SNGG soils, suggesting that microbial assimilation of $NH_4^+$ is predominant compared to nitrification when available C-source is abundant. These results suggest application of chemical fertilizer-N with organic amendment would have beneficial effect on soil-N retention and environmental conservation by reducing production of $NO_3^-$ which is likely to be lost through leaching or denitrification.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.115-122
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• 2019

In order to improve the current efficiency and reduce the energy consumption in the electrosynthesis of ammonium persulfate, electrolytic properties of a perfluorosulfonic cation exchange membrane named PGN membrane and the $Al_2O_3$ ceramic membrane in the electrosynthesis of ammonium persulfate were studied and compared in a pilot electrolytic cell using a welded platinum titanium as the anode and a Pb-Sb alloy as the cathode. The effect of cell voltage, electrolyte flow rate and electrolysis time of the electrolytes on the current efficiency and the energy consumption were studied. The results indicated that the PGN membrane could improve current efficiency to 95.12% and reduce energy consumption to $1110kWh\;t^{-1}$ (energy consumption per ton of the ammonium persulfate generated) under the optimal operating conditions and the highest current efficiency of the $Al_2O_3$ ceramic membrane was 72.61% with its lowest energy consumption of $1779kWh\;t^{-1}$. Among 5 times of the electrolysis of the electrolytes, the lowest current efficiency of the PGN membrane was 85.25% with the highest energy consumption of $1244kWh\;t^{-1}$ while the lowest current efficiency of the $Al_2O_3$ ceramic membrane was 67.44% with the highest energy consumption of $1915kWh\;t^{-1}$, which suggested the PGN membrane could be used in the 5-stage electrolytic cell for the industrially continuous electrosynthesis of ammonium persulfate. Therefore the PGN membrane can be efficient to improve the current efficiency and reduce the energy consumption and can be applied in the industrial electrosynthesis of ammonium persulfate.

• 한국토양비료학회지
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• 제17권3호
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• pp.242-252
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• 1984

수도(水稻) 재배시(栽培時) 요소(尿素)를 비롯하여 초안(硝安), 염안(鹽安) 등(等) 다른 형태(形態)의 질소질(窒素質) 비료(肥料)와 비교(比較)하여 유안(硫安)의 비효(肥效)를 새로이 검토(檢討)하고, 토양(土壤) 산성화(酸性化)의 문제(問題)를 검토(檢討)하기 위(爲)하여 풍산(豊山)벼를 공시품종(供試品種)으로 하여 pot 시험(試驗)한 결과(結果)는 다음과 같다. 1. 수도(水稻) 생육기간중(生育期間中) 토양(土壤) 및 표면수(表面水)의 pH 변화(變化)는 시비(施肥) 직후(直後)에 요소(尿素), 초안(硝安), 유안(硫安), 염안(鹽安) 처리순(處理順)으로 낮으며 그 차이(差異)가 컸으나 시비후(施肥後) 1주일(週日)이 지나면 평형(平衡)에 도달(到達)하여 질소질(窒素質) 비료(肥料)의 종류간(種類間)에 pH차이(差異)가 거의 없었다. 2. 풍건(風乾) 토양(土壤)의 pH는 요소(尿素), 초안(硝安), 염안(鹽安), 유안(硫安) 처리순(處理順)으로 낮았으며, 그 차이(差異)가 생육후기(生育後期)로 갈수록 커지는 경향(傾向)이었으나 현저(顯著)한 차이(差異)는 아니었다. 3. 토양(土壤)과 식물체중(植物體中) 유황(硫黃) 함량(含量)은 전(全) 재배기간(栽培其間)을 통(通)하여 유안구(硫安區)에서 가장 높았으며, 토양중(土壤中) 전(全) 질소함량(窒素含量)은 질소질(窒素質) 비료(肥料)의 종류간(種類間)에 차이(差異)가 없었으나 식물체중(植物體中) 질소(窒素) 함량(含量)은 유안구(硫安區)에서 유의성(有意性) 있게 높았다. 4. 초장(草長)은 질소질(窒素質) 비료(肥料)의 종류간(種類間)에 차이(差異)가 없었으나 분얼수(分蘖數)는 유안구(硫安區)에서 가장 많았고 식물체(植物體) 건물중(乾物重)도 수도(水稻) 전(全) 생육기간(生育時間)에 걸쳐 유안구(硫安區)가 다른 모든 처리구(處理區)에 비(比)해 유의성(有意性)있게 높았다. 5. 유안구(硫安區)는 주당수수(株當穗數)가 다른 처리구(處理區)에 비해 유의성(有意性) 있게 많았고 따라서 수량(收量)도 가장 높았다. 반면(反面)에 초안구(硝安區)는 주당수수(株當穗數) 및 등숙률(登熟率)이 매우 낮았기 때문에 정조수량(正租收量)이 현저하게 낮았다.

• 한국토양비료학회지
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• 제18권1호
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• pp.63-66
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• 1985

요소(尿素)와 질산(窒酸)암모늄(질안(窒安))이 토양가리(土壤加里)의 이용율(利用率) 및 배추의 수량(收量)에 주는 영향(影響)을 밝히고자 포트시험(試驗)을 한 결과(結果)는 다음과 같다. 1. 질안(窒安)은 요소(尿素)보다 토양(土壤)의 pH를 낮추고 배추에 대(對)한 토양가리(土壤加里)의 이용도(利用度)를 높여서 무가리(無加里) 재배(栽培)에서의 배추의 수량(收量)을 높였다. 2. 배추속(가식부(可食部))을 충실(充實)히 하는데 질안(窒安)은 요소(尿素)보다 더 효과적(效果的)인것 같고 동효과(同效果)는 가리(加里)가 병용(倂用)되므로서 더 현저(顯著)해졌다. 3. 배추의 가식부수량(可食部收量)은 건조(乾燥)배추의 N/K 당량비(當量比)가 낮을수록 많았으며 동비(同比) 약(約) 1.4에서 높은 수량(收量)이 얻어졌다. 이때 건조(乾燥)배추의 K-함량(含量)의 1.2~1.3me/g이었다.

• 한국토양비료학회지
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• 제49권3호
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• pp.282-286
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• 2016

This study was carried out to evaluate the effect of application of urea and combination of urea and pig manure compost (PMC) on the occurrence of and the recovery from ammonium ($NH_4{^+}$) toxicity in Chinese cabbage. To identify $NH_4{^+}$ toxicity of the crop four levels of urea at 0, 160, 320, and $480kg\;N\;ha^{-1}$ were applied, in addition, three levels of PMC at 10, 20, and $40M/T\;ha^{-1}$ was also applied with urea $320kg\;ha^{-1}$. For recovery $NH_4{^+}$ toxicity, six levels of sucrose were treated at the amount of 0, 600, 1,200, 1,800, 2,400, and $3,000kg\;C\;ha^{-1}$ at each level of combining treatments of urea and PMC. Our results showed that $NH_4{^+}$ toxicity was occurred at every urea application of $320kg\;N\;ha^{-1}$ regardless of PMC applied to the soils because $NH_4{^+}$ contents in the soils were more than $155mg\;kg^{-1}$ which was found to be the critical level to damage crop growth at 2 days after transplanting (DAT) in this experiment, the more sucrose was applied up to $1,800kg\;C\;ha^{-1}$ for the plants damaged by ammonium toxicity occurred at $320kg\;N\;ha^{-1}$, the greater extents recover the plants from the toxicity. PMC showed the similar effect with sucrose on recovering Chinese cabbage plants from $NH_4{^+}$ toxicity at 30 DAT.

• 공업화학
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• 제16권4호
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• pp.496-501
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• 2005

Iron계 금속 촉매의 존재 하에서 ABS의 열분해 거동을 TGA (Thermogravimetric Analysis)를 통해서 조사하였다. Iron계 금속 촉매(ferric nitrate nonahydrate, ammonium ferric sulfate dodecahydrate, iron sulfate hydrate, ammonium ferric oxalate, iron(II) acetate, iron(II) acetylacetonate 및 ferric chloride)는 ABS의 열분해 과정에서 화학반응을 야기하여, 질소분위기에서 촤(char)형성이 관찰되었으며, $600^{\circ}C$에서 3~23 wt%의 비휘발성 촤를 형성하였다. 이와 같은 질소분위기에서의 ABS의 촤 생성은 iron계 금속 촉매의 가교효과(crosslinking effect)로 추정된다. 한편, 공기분위기에서는 생성된 촤가 고온 산화반응에 의해서 열분해되었다.

• 농약과학회지
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• 제17권1호
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• pp.20-26
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• 2013

본 시험은 충북지역 포도원 잡초방제별 생육 및 수량에 미치는 영향을 구명하기 위해 2010년부터 2011년까지 포도연구소(충북 옥천군 청성면 산계리 소재)에서 3년생 캠벨얼리가 구당 2주가 식재된 포도원에서 18개 구획(구획당 가로 3.5 m, 세로 5.5 m)에서 수행되었다. 제초제처리구는(Glufosinate ammonium SL 18.0%, Paraquat dichloride SL 23.1%)를 각각 3회 살포, 부직포 피복구, 들묵새 초생재배구, 기계제초구(3회), 무처리구로 포도의 생육 및 수량 및 7~8월 우점잡초와 처리별 방제효과를 조사하였다. 잡초는 총 16종으로 생육초기인 5월 하순경에는 명아주, 크로버가 우점하였고, 생육중기인 7월 중순에는 망초, 피, 명아주가 우점하였으며 생육후기에도 망초, 피, 명아주가 우점하였다. 3차 방제 후 10일차 방제효과는 부직포 100%, 들묵새 95.3%, 기계제초 81.9%, glufosinate ammonium 가 98.1%, paraquat dichloride 처리가 90.4%로 나타났다. 캠벨얼리의 생육은 주간경, 절간장, 절간경, 엽장, 엽폭 그리고 신초장을 개화전과 수확 후를 비교하였으며, 그 결과 제초제 처리구와 기계제초구에서 전반적으로 생육이 좋았다. 수량은 1주당 glufosinate ammonium, paraquat dichloride 3회 처리구에서 각각 12.7 kg, 12.3 kg로 다른 처리구보다 높은 경향이었다.