• 농약과학회지
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• 제2권1호
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• pp.53-58
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• 1998

Dicamba의 부작용을 최소화하고, 약효지속효과를 증진하며, 유효성분의 용출속도를 조절할 수 있는 전분을 중합매체로 한 방출조절형 dicamba 입제를 제조하여 기존의 dicamba 액제와 용탈, 토양잔류 및 휘산을 비교하였다. 이들 방출조절형 dicamba 입제는 dicamba 액제에 비하여 약 50% 이상 용탈이 감소되었으며, 토양잔류는 양토에 처리된 dicamba 입제의 토양중 반감기가 $50{\sim}51$일 이었으며, 사양토에 처리하였을때는 $50{\sim}58$일 이었다. 한편 양토 및 사양토에 처리된 dicamba 액제는 각각 24일과 22일 이었다. 또한 dicamba의 휘산성은 방출조절형 dicamba 입제가 dicamba 액제에 비하여 약 10배의 휘산억제효과가 있었다.

• 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.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.94-103
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• 2016

Landfarming that supplies aerobic biodegradation condition to indigenous microbes in soils is a biological remediation technology. In this research, volatilization and biodegradation rate by indigenous microbes in the soil contaminated with total petroleum hydrocarbons (TPH) were measured. Soils were contaminated with diesel artificially and divided into two parts. One was sterilized by autoclave to remove indigenous microorganism and the other was used as it was. Various moisture contents and number of tillings were applied to the soil to find out proper condition to minimize volatilization and enhance bioremediation. Volatilization of TPH was inhibited and biodegradation was enhanced by increase on moisture content. Tilling was usually used to supply air for microbes, but tillings did not affect the growth of microbes in our study. Enough moisture content and proper aeration are important to control volatilization in landfarming. Also, TPH degradation was a function of the microbe counts (x₁), numbers of tilling (x₂), and moisture content (x₃) from the application of the response surface methodology. Statistical results showed the order of significance of the independent variables to be microbe counts > numbers of tilling > moisture content.

• 농업과학연구
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• 제50권3호
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• pp.437-446
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• 2023

As the interest in sustainable and environmentally friendly agriculture continues to grow, there is a corresponding increase in organic fertilizers utilization. However, studies on ammonia (NH₃) emissions, which are primarily generated in the agricultural sector, by organic fertilizers are lacking. Additionally, the reliance on imported ingredients in the production of organic fertilizers hinders the widespread adoption of organic fertilizers. This study aims to evaluate NH₃ volatilization by incorporating rice husk biochar into organic fertilizers. The study also aims to assess whether domestically produced rice husk biochar can serve as a viable substitute for imported ingredients. Here, the dynamic chamber method was used under controlled conditions. Results show that inorganic fertilizers readily undergo hydrolysis, thereby rapidly generating significant amounts of NH₃, particularly in the initial stages. In contrast, organic fertilizers decompose gradually, leading to relatively long-term NH₃ emissions. The incorporation of rice husk biochar into organic fertilizers demonstrated diminished daily NH₃ emissions compared to those from commercial organic fertilizers, resulting in decreased total NH₃ volatilization. These findings show that the combination of rice husk biochar can reduce NH₃ volatilization and serve as an alternative to imported ingredients for organic fertilizers. The results of this study can be utilized as fundamental information for the assessment of biochar as a potential ingredient for organic fertilizers.

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.684-689
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• 2012

In the present study, an efficient mercury-tolerant bacterial strain (RS-5) was isolated from heavy-metalcontaminated industrial effluent. Under shake flask conditions, 97% of the supplemented mercuric chloride was sequestered by the biomass of RS-5 grown in a tryptone soy broth. The sequestered mercuric ions were transformed inside the bacterial cells, as an XRD analysis of the biomass confirmed the formation of mercurous chloride, which is only feasible following the reaction of the elemental mercury and the residual mercuric chloride present within the cells. Besides the sequestration and intracellular transformation, a significant fraction of the mercury (63%) was also volatilized. The 16S rRNA gene sequence of RS-5 revealed its phylogenetic relationship with the family Bacillaceae, and a 98% homology with Lysinibacillus fusiformis, a Gram-positive bacterium with swollen sporangia. This is the first observation of the sequestration and volatilization of mercuric ions by Lysinibacillus sp.

• 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.

• 한국안전학회지
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• 제8권4호
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• pp.175-182
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• 1993

Volatilization of toxic heavy metals, especially, metal chlorides at elevated temperatures in oxidation conditions was observed using a thermogravimetric furnace since such metal chlorides used to be a cause for the disease of industrial workers by their toxicity and high volatile extent. Most of tested metal chloride compounds were evaporated or decomposed into gas phase at elevated temperatures ranged from 200~90$0^{\circ}C$, while CrCl$_3$ and NiC1$_2$became stable with converting into oxide forms. A kinetic model for evaporation/condensation could predict maximum evaporation flux and the calculated values were compared with real evaporation flux. The ratio of two fluxes could be explained as the fraction of impinging gas molecules to the condensing surface( $\alpha$ ) and obtained in the range of 10$^{-3}$ ~10$^{-9}$ for the experimented toxic heavy metal chlorides. This ratio might be used to define the volatile extent or toxicity of such toxic metal compounds. The schemes to avoid volatilization of toxic heavy metals Into the atmosphere were suggested as follows ; 1 ) controlling the compositions of metals and Chlorine produced substances( such as PVC ) in the treated materials using a reverse estimation from regulatory limit and characteristics of a processing facility, 2) Installation of wet type devices such as a scrubber for condensing the metal compounds.

• 한국재료학회지
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• 제33권4호
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• pp.135-141
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• 2023

The volatilization of alkali ions in (K,Na)NbO₃ (KNN) ceramics was inhibited by doping them with alkaline earth metal ions. In addition, the grain growth behavior changed significantly as the sintering duration (t_s) increased. At 1,100 ℃, the volatilization of alkali ions in KNN ceramics was more suppressed when doped with alkaline earth metal ions with smaller ionic size. A Ca²⁺-doped KNN specimen with the least alkali ion volatilization exhibited a microstructure in which grain growth was completely suppressed, even under long-term sintering for t_s = 30 h. The grain growth in Sr²⁺-doped and Ba²⁺-doped KNN specimens was suppressed until t_s = 10 h. However, at t_s = 30 h, a heterogeneous microstructure with abnormal grains and small-sized matrix grains was observed. The size and number of abnormal grains and size distribution of matrix grains were considerably different between the Sr²⁺-doped and Ba²⁺-doped specimens. This microstructural diversity in KNN ceramics could be explained in terms of the crystal growth driving force required for two-dimensional nucleation, which was directly related to the number of vacancies in the material.

• 한국환경과학회지
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• 제32권10호
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• pp.741-744
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• 2023

This study focused on high school laboratory research and the main purpose was to develop alternative additives for livestock waste and ammonia volatilization methods with high school students as participants and to provide information to business owners based on the results. Compared to the control groups, The bentonite and illite treatment groups had similar ammonia volatilization, pH, EC, and total nitrogen content. In particular, the alum and aluminum chloride mixed treatment group showed low pH and ammonia volatilization, and high EC and total nitrogen content for poultry litter. As a result, when focusing on high school laboratory research, the alum and aluminum chloride mixed agent treatment fulfilled its role as an alternative additive for ammonia reduction. In addition, this approach can be suggested as a method to solve difficulties in adapting to the field through a practical cooperative relationship with livestock farms.

• 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.