• Proceedings of KOSOMES biannual meeting
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• 2004.05b
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• pp.81-84
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• 2004

Control of Sediment is very important in prawn farm due to the eruption of toxic material such as W1ionized H2S, NH3 and NO2-. In this study, column test study, column with filter media such as activated carbon, zeolite, oyster shell and iron chloride to evaluate the reduction of toxicity from sediment ammonia-N(NH3) was effectively removed by Zeolite and oyster shell. It was indicated that ammonium ion(NH4+) was removed by ion exchange of zeolite. And the ammonia in the column of oyster shell was existed as the form of NH4+, which is not toxic for prawn because oyster shell was stably kept around pH 8. Therefore, some of ammonia(NH3) was reduced by oyster shell. Hydrogen sulfide and COD were effectively removed by adsorption of activated carbon and a partial removal of hydrogen sulfide was accomplished by Oyster shell. Phosphorous was removed by activated carbon, oyster shell and iron chloride. In prawn farm, the concentration of ammonia was increased with increase of pH by algae photosynthesis in the column of activated carbon, zeolite and iron chloride, but it was revealed that pH was stably kept in the column of oyster shell.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.344-352
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• 2014

The aim of the present study was to assess the effects of ammonia on physiological responses in Korean rockfish (Sebastes schlegeli). Interestingly, no mortality were observed when the specimens ($301.1{\pm}8.0g$) were exposed to five levels of un-ionized ammonia ($NH_3$) (control, 1, 2, 4, $8mg\;L^{-1}$) for 3 hours. Furthermore, a significantly higher increase in gill $Na^+/K^+$-ATPase (NKA) pump activity with was detected due to the ammonia exposure. The activity of the fishes were found to be 4 and $8mg\;L^{-1}$ $NH_3$, which was significantly high compared to normal $1mg\;L^{-1}$ $NH_3$. Although ammonia exposure had no effect on plasma $Cl^-$, exposure to both 4 and $8mg\;L^{-1}$ $NH_3$, however it led to increase in the plasma $Na^+$, $K^+$ and osmolality levels. Also, prolong ammonia exposure cause increase of plasma cortisol and glucose levels. The increase in glucose was accompanied by an increase in cortisol. The fish exposed to 4 and $8mg\;L^{-1}$ $NH_3$ showed significantly higher hematocrit than control group than those exposed to 1 and $2mg\;L^{-1}$ $NH_3$. The intensity of cell damage increased with the increase concentration and exposure to ammonia. Furthermore, hyperplasia, separation and epithelial necrosis were also observed in gill tissues. Taken together, the results showed that direction of changes to the investigated parameters can be used to determine the physiological responses of Korean rockfish to ammonia.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.846-850
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• 2006

The biological nutrient removal from domestic wastewater with low C/N ratio is difficult. Therefore, this study was performed to increase influent C/N ratio by ammonia stripping without required carbon source and for improving treatment efficiencies of sewerage by the combination process of ammonia stripping and BNR (StripBNR). The results of this study were summarized as follows. BOD removal efficiencies of BNR and StripBNR were 95.3% and 93.2%, respectively. T-N and T-P removal efficiencies of BNR were 53.3% and 40.8%, respectively. T-N and T-P removal efficiencies of StripBNR were 72.8% and 62.9%, respectively. Concentrations of $NH_3-N$, $NO_2-N$ and $NO_3-N$ at BNR effluent were 0.03 mg/L, 0.08 mg/L and 9.12 mg/L, respectively. On the other hands, concentrations of $NH_3-N$, $NO_2-N$ and $NO_3-N$ at StripBNR effluent were 5.79 mg/L, 0.01 mg/L and 0.14 mg/L, respectively. Consequently, influent C/N ratio of BNR process was increased by ammonia stripping. Removal efficiency of T-N and T-P was improved about 20% by the process of StripBNR.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.775-778
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• 2012

The potential energy surfaces of ammonia molecule adsorptions on the symmetrically chlorinated Si(100)-$2{\times}1$ surface were explored with SIMOMM:MP2/6-31G(d). It was found that the initial nucleophilic attack by ammonia nitrogen to the surface Si forms a $S_N2$ type transition state, which eventually leads to an HCl molecular desorption. The second ammonia molecule adsorption requires much less reaction barrier, which can be rationalized by the surface cooperative effect. In general, it was shown that the surface Si-Cl bonds can be easily subjected to the substitution reactions by ammonia molecules yielding symmetric surface Si-$NH_2$ bonds, which can be a good initial template for subsequent surface chemical modifications. The ammonia adsorptions are in general more facile than the corresponding water adsorption, since ammonia is better nucleophile.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.488-495
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• 1997

The effects of ammonia on survival and growth of the flounder larva, Paralichthys olivaceus, were examined by a static renewal bioassay method. The $96\;hr-LC_{50}$ with the developmental stages during the period from 1day to 23 day-old larvae ranged 0.273 to 1.023 mg $NH_3/\ell$. Tolerance of the larvae to ammonia toxicity was much sensitive at the early larval stage, and increased with the growth of the larvae. Threshold $96hr-LC_{50}$ in 1, 3 and S day-old larvae after hatching were 0.293, 0.248 and 0.379 mg $NH_3/\ell$, respectively. Survival rate and growth in body weight and body weight of the larva were reduced with increase of ammonia concentration in the range of 0.055 and 0.341 mg $NH_3/\ell$. The no-observable-effect concentration (NOEC) and lowest-observable- effect concentration (LOEC) of the flounder larve were 0.102 and 0.174 mg $NH_3/\ell$ for body length, and 0.151 and 0.198 mg $NH_3/\ell$ for body weight, respectively. Chronic value (ChV), which is the geometric mean of the NOEC and $NH_3/\ell$ to body length of the larvae were 0.124 mg $NH_3/\ell$. The coefficient of variation (CV) for body length was higher at high concentration than at low concentration.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.329-338
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• 2009

Emission of ammonia to the atmosphere are considered a threat to the environment. The application of livestock manure and compost contributes significantly to the emission of ammonia from agriculture. The reduction in NH3 losses from field-applied manure and compost would be a good strategy to reduce national $NH_3$ emission. In this study, various application techniques of liquid manure and compost were compared to evaluate their potential for reducing $NH_3$ emission. In compost application, the reductions in $NH_3$ emission were 70 and 15% for immediately rotary after application (IRA) and rotary at 3-day after application (RA-3d) in comparison with surface application (SA). Total ammonia emissions for 13 days, expressed as % ammonia-N applied in compost, were 42, 35.7, and 12.7% for SA, RA-3d, and IRA treatments, respectively. Mean reductions in NH3 emission from application of liquid pig manure were 26 and 50% for rotary harrow after surface broadcast application in spring and fall, respectively, in comparison with surface broadcast application. Ammonia emission rate was decreased with increasing water content in soil due to dilution effect, but this reduction only was temporary up to 12 hours after application and cumulative $NH_3$ emission was increased with increasing water content in soil. However, the delay would be beneficial because it allows time for rotary hallow of the applied liquid pig manure. Therefor, ammonia emission can be reduced by immediately incorporation of liquid manure and compost after surface application.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.394-394
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• 2010

Ammonium ion (${NH_4}^+$) was suggested as the origin of interstellar $6.85\;{\mu}m$ band. Early study, in which organic molecule and water ice film mixtures were photolyzed so that organic acids could be produced, explained the generation of ${NH_4}^+$ from the reaction of photogenerated organic acid and ammonia ($NH_3$). However, the observed abundance of organic acids or their counter-anions are not so high in interstellar ice and not enough to protonate $NH_3$ into ${NH_4}^+$ in the observed level. Because of the shortage in photogenerated organic acids, the candidate of acid which protonates $NH_3$ should be modified. Here, we prepare $NH_3/H_2O$ binary mixtures and photolyze them with vacuum ultraviolet (VUV, peak at 10.6 and 10.0 eV). We find the ammonium ion (${NH_4}^+$) from photolyzed mixture by using low energy sputtering (LES) and reflection absorption IR spectroscopy (RAIRS). As a hydronium ($H_3O^+$) can be produced by UV irradiation and protonate bases, ${NH_4}^+$ may be formed from the reaction of photogenerated $H_3O^+$ and $NH_3$. We show the generation of ${NH_4}^+$ without any kind of organic molecules or acids, and it may explain the relatively high abundance of ${NH_4}^+$ compared to the counter-anions or organic acids in interstellar ice.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.3
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• pp.145-149
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• 2018

The objective of this study was to determine the effect of injection application of pig slurry on ammonia ($NH_3$) and nitrous oxide ($N_2O$) emission from timothy (Phleum pretense L.) sward. The three treatments were applied: 1) only water as a control, 2) pig slurry application by broadcasting, 3) pig slurry application by injection. The pig slurry was applied at a rate of $200kg\;N\;ha^{-1}$. Total $NH_3$ and $N_2O$ emission, expressed as a cumulative amount throughout the measurement time (40 days), was $2.68kg\;NH_3-N\;ha^{-1}$ and $6.58g\;N_2O-N\;ha^{-1}$, respectively, in the control. The injection application of pig slurry decreased total $NH_3$ and $N_2O$ emission by 39.8% and 33.3%, respectively, compared to broadcasting application of pig slurry. The present study clearly showed that injection application exhibited positive roles in reducing N losses through $NH_3$ and $N_2O$ emission.

• Journal of Environmental Science International
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• v.31 no.10
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• pp.833-844
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• 2022

A zeolite material with a Si/Al molar ratio of 1.2 was synthesized by changing the NaOH/CFA ratio of coal fly ash (CFA) via a fusion/hydrothermal reaction in the HD thermal power plant. The change in the crystal structure of the zeolite was confirmed using XRD and SEM, and the ammonia adsorption capacities of the synthesized zeolitic materials and a commercial zeolite (Na-A zeolite) were analyzed via an ammonia temperature-programmed desorption (NH₃-TPD) process. The SEM and XRD results revealed out the zeolitic materials from the coal fly ash maintained a hexagonal Linde-type crystal structure similar to that of Na-A zeolite, but the crystallinity of the synthesized zeolitic material was reduced due to impurities. The NH₃ adsorption capacity, determined from the NH₃-TPD analysis of was 1.122 mmol/g of the synthesized zeolitic material, which was lower than the NH₃ adsorption capacity of the Na-A zeolite.

• Applied Chemistry for Engineering
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• v.8 no.1
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• pp.23-28
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• 1997

The adsorption characteristics of ammonia-Cu(II) complex on activated carbon were studied. Firstly, the specific surface area of the activated carbon was measured by using the BET adsorption apparatus. Secondly, the characteristics of the removal copper(II) ion from aqueous ammonia solution by forming a complex with ammonia and then by the adsorption of the complex on the activated carbon were studied. It was found that the specific surface area increases with decreasing the mesh number of the activated carbon, and the optimum pH for the adsorption of the Cu(II) ion on she activated carbon was found to be approximately 6. It was also found that the adsorbed Cu(II)-ammonia complexes on the activated carbon in the aqueous ammonia solution have two types, depending on the concentration of the solution ; i.e. $[Cu(NH_3){_2}]^{2+}$and $[Cu(NH_3){_3}]^{2+}$ for $2.25{\times}10^{-4}(mol/{\ell})$and $2.25{\times}10^{-3}(mol/{\ell})$, respectively.