• 대한화학회지
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• 제31권3호
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• pp.271-279
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• 1987

Amine기를 가진 Bakelite A와 Ni(II) 사이의 착물을 이용한 ${NO_3}^-$이온 선택성 막전극을 만들었다. 이 막전극은 $H^+$ 이온 및 2가 3가 음이온에는 감응하지 않으며, 특히 이 막전극의 재현성, 감응시간 및 이온선택성등 전기화학적 성질을 조사하여 다른 실용화된 막전극과 비교 고찰하였으며 분석화학에의 응용을 고찰하였다.

• 약학회지
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• 제39권2호
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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.

• 한국연초학회지
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• 제20권2호
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• pp.231-237
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• 1998

This study was carried out to investigate the effects of curing methods on the concentration of ammonia during curing in burley tobacco leaves. The air-cured tobacco(KB108; Nicotiana tabacum L.) was grown at Chonju Tobacco Experiment Station in 1998 and the tenth leaves from the top on the stalk were harvested. Half of the harvested leaves were cured in normal air curing facility and the other leaves were cured in excessive curing facility. Stalk cut tobaccos were cured in horizontal curing facility. The leaves were sampled every five days from harvesting time to the end of curing(25 days). Ammonia concentration of leaves increased during curing period with a remarkable increase at yellowing stage. The concentration of ammonia was high in the primed cured leaves, while that of the excessive cured leaves was low. It is considered that the lower increase of ammonia in stalk cured leaves may be caused by the translocation from the leaves to the stalk during curing, while that of excessive cured leaves may be caused by the poor decomposition of protein and amino acid during curing by excessive moisture loss and high temperature condition.

• Environmental Engineering Research
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• 제11권6호
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• pp.311-317
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• 2006

Feasibility of destroying synthetic and actual leachate containing humic acids and ammonia compounds by supercritical water oxidation (SCWO) was evaluated. In this study, destruction efficiencies of humic acids and ammonia respectively were investigated at various reaction temperatures and residence times under pressure a supercritical pressure (280 atm). To lower reaction temperature, chemical oxidants were used. The experiment was carried out in a cylindrical batch reactor made of Hastelloy C-276 that can withstand high temperature and pressure. Concentrations of humic acids and ammonia were measured using a $COD_{Cr}$ method and an ammonia selective electrode, respectively. The optimal destructive condition of humic acids in the presence of stoichiometric oxygen(air) was 3 min at $380^{\circ}C$, but the temperature could be lowered to subcritical region ($360^{\circ}C$) along with $H_2O_2$ as an oxidant. For ammonia, the optimal destructive condition with air was 5 min at $660^{\circ}C$, but it was possible to operate the process for 3 minutes at $550^{\circ}C$ or 2 min at $600^{\circ}C$ along with $H_2O_2$ as an oxidant. At 2 min and $550^{\circ}C$ along with $H_2O_2$ as an oxidant, humic and ammonia compounds in the actual leachate were easily destructed and the effluent quality met the Korea Standard Leachate Quality.