• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1202-1208
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• 2015

The effects of daily dietary Bacillus subtilis (Bs), and adding L-tryptophan, fructan, or casein to fecal fermentation broths were investigated as means to reduce the production of noxious gas during manure fermentation caused by ammonia, hydrogen sulfide ($H_2S$), and 3-methylindole (skatole). Eighty swine ($50.0{\pm}0.5kg$) were equally apportioned to an experimental group given Bs in daily feed, or a control group without Bs. After 6 weeks, fresh manure was collected from both groups for fermentation studies using a $3{\times}3$ orthogonal array, in which tryptophan, casein, and fructan were added at various concentrations. After fermentation, the ammonia, $H_2S$, L-tryptophan, skatole, and microflora were measured. In both groups, L-tryptophan was the principle additive increasing skatole production, with significant correlation (r = 0.9992). L-tryptophan had no effect on the production of ammonia, $H_2S$, or skatole in animals fed Bs. In both groups, fructan was the principle additive that reduced $H_2S$ production (r = 0.9981). Fructan and Bs significantly interacted in $H_2S$ production (p = 0.014). Casein was the principle additive affecting the concentration of ammonia, only in the control group. Casein and Bs significantly interacted in ammonia production (p = 0.039). The predominant bacteria were Bacillus spp. CWBI B1434 (26%) in the control group, and Streptococcus alactolyticus AF201899 (36%) in the experimental group. In summary, daily dietary Bs reduced ammonia production during fecal fermentation. Lessening L-tryptophan and increasing fructan in the fermentation broth reduced skatole and $H_2S$.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.75-80
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• 2019

The article is devoted to the interpretation of ammonia, one of the fine dust precursors, absorption behavior in water turbulent flow. The water flow was considered as a turbulent flow with Reynolds number more than $10^4$, because ammonia gas penetration depth was deeper at turbulent flow compared to laminar flow. For the interpretation, the dimensionless mass transfer governing-equation and the constant physical-properties at room temperature were used. The diffusivity of ammonia in water and the kinematic viscosity of water were $2{\times}10^{-9}m^2/s$ and $1{\times}10^{-6}m^2/s$, respectively. The concentration distribution of ammonia in water was estimated with respect to the position from the point where the water started to be exposed to ammonia. The quantitative distribution as a function of the mixing length was also acquired. The quantitative interpretation may provide the insight how much the turbulent flow was more efficient to remove ammonia rather than the laminar flow.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.4
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• pp.357-362
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• 2018

In this study, computer simulation and optimization works have been performed for a refrigeration cycle using ammonia as a refrigerant and also how much power was saved when the liquefied natural gas cold heat is replaced for the refrigeration cycle. PRO/II with PROVISION release 10.0 from Schneider electric company was used, and Peng-Robinson equation of the state model was selected for the modeling of the refrigeration cycle and LNG cold heat utilization process.

• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.55-62
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• 2006

A two-step fuel-rich/fuel-lean catalytic combustion seems to be one of the most effective methods to control simultaneously the NO generation and the hydrocarbon (HC) conversion from fuel-bound nitrogen. By controlling equivalent air ratio for maintaining fuel-rich and fuel-lean condition over each catalytic layer, space velocity, inlet temperature, and catalyst component, the HCand ammonia conversion efficiency higher than 95% could be achieved, with ammonia conversion to NO remaining below 5%. The experimental results wouldbe applied to the combustion of land fill gas and to gasified refuse-derived fuels as a method of minimizing NO generation.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.113-117
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• 1995

Garlic tissue cells are employed for the conversion of L-asparagine into ammonia. An ammonia gas electrode is used as a detector. The effect of pH, buffer solution, temperature and life time of electrode to have used were investigated in order to optimize the electrode response. The combination of L-asparaginase in garlic tissue cells and the gas electrode response linearly to Lasparagine over the concentration range 1.0$\times$10$^{-4}$~1.0$\times$10$^{-1}$ M with a slope of 72.0 mV/decade and is selective with respect to other L-amino acids.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.61-63
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• 2015

In the low pressure selective catalytic reduction (LP SCR) system, the uniformity of both ammonia concentration and exhaust gas flow at the SCR catalyst layer are important design factor for the efficient SCR-deNOx performance. According to the shape of the guide vane and static mixer, numerical simulations were conducted to analyze flow patterns and finally to find out the appropriate alternative for uniform flow at the front of catalyst in the real scale LP SCR reactor. The variations of gas velocity and ammonia concentration were quantitatively evaluated. Based on the present results, the shape was devised to satisfy the design criteria.

• Korean Journal of Environmental Agriculture
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• v.41 no.1
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• pp.41-49
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• 2022

BACKGROUND: The main source of ammonia in soils, South Korea is agricultural emissions (e.g., fertilizer application and livestock manure), with the recent emission inventories reporting them to be approximately 80% of the total emissions. Ammonia as a pollutant is originated largely from agricultural activity and is an important contributor to air quality issues in South Korea. The importance of ammonia in agricultural land is also emerging. In this study, the characteristics of ammonia emission from Chinese cabbage cultivation fields with application rates of urea sere were evaluated. METHODS AND RESULTS: The ammonia emission characteristics were investigated at the different urea application rates (0, 160, 320, and 640 kg ha-1) and the ammonia emission factor in the Chinese cabbage cultivation field was calculated. As application rate of urea application increased, ammonia emissions increased proportionally. In 2020 and 2021, cumulative ammonia emissions with urea 320 kg ha^-1 treatment were 39.3 and 35.2 kg ha^-1, respectively for 2020 and 2021. When urea fertilizer was applied, the ammonia emission factors were 0.1217 and 0.1358 NH₄⁺-N kg N kg^-1 in 2020 and 2021, respectively. CONCLUSION(S): Ammonia emissions increased as application rate of urea increased, and the average ammonia emission factor of the Chinese cabbage cultivation field for two years was 0.129 NH₄⁺-N kg N kg^-1.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.07a
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• pp.281-286
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• 2001

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.12a
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• pp.244-249
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• 1998

• Proceedings of the Korean Fiber Society Conference
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• 2001.04b
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• pp.71-74
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• 2001