• Journal of Animal Environmental Science
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• 제12권2호
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• pp.85-94
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• 2006

The effects of turning frequency of in-vessel composting on ammonia emissions during composting of separated solids from swine slurry/sawdust mixtures and performance of biofiltration using the chicken manure compost were investigated. Separated solids from swine manure amended with sawdust was composted in a 226 L laboratory-scale in-vessel reactors under various turning frequency and continuous airflow (0.6 L/min.kg.dm) for three weeks. Three laboratory-scale manure compost biofilters were built to treat effluent gas from the composting of separated solid from swine manure amened with sawdust process. These experiments were continued over a period of three weeks. The composting of separated solid swine manure amended with sawdust and manure compost biofiltration system were evaluated to determine the turning frequency type that would be adequate for the rate of decomposition and compost odour reduction. The compost odour cleaning was measured based on ammonia gas concentration before and after passing through the manure compost biofilter. The average ammonia odor reduction in the manure compost biofilter was 96.9 % at R1 (no turning), 99.4 % at R2(once a day turning) and 89.0 % at R3(twice a day turning), respectively. The efficiency of ammonia reduction was mainly influenced by the turning frequency.

• Journal of Microbiology and Biotechnology
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• 제23권5호
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• pp.719-723
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• 2013

Nitrification in wastewater treatment emits a significant amount of nitrous oxide ($N_2O$), which is one of the major greenhouse gases. However, the actual mechanism or metabolic pathway is still largely unknown. Selective nitrification inhibitors were used to determine the nitrification steps responsible for $N_2O$ emission with activated sludge and enriched nitrifiers. Allylthiourea (86 ${\mu}M$) completely inhibited ammonia oxidation and $N_2O$ emission both in activated sludge and enriched nitrifiers. Sodium azide (24 ${\mu}M$) selectively inhibited nitrite oxidation and it led to more $N_2O$ emission than the control experiment both in activated sludge and enriched nitrifiers. The inhibition tests showed that $N_2O$ emission was mainly related to the activity of ammonia oxidizers in aerobic condition, and the inhibition of ammonia monooxygenase completely blocked $N_2O$ emission. On the other hand, $N_2O$ emission increased significantly as the nitrogen flux from nitrite to nitrate was blocked by the selective inhibition of nitrite oxidation.

• Carbon letters
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• 제21권
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• pp.1-7
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• 2017

The effects of ammonia-treated graphene oxide (GO) on composites based on epoxy resin were investigated. Ammonia solutions of different concentrations (14-28%) were used to modify GO. Nitrogen functional groups were introduced on the GO surfaces without significant structural changes. The ammonia-treated GO-based epoxy composites exhibited interesting changes in their mechanical properties related to the presence of nitrogen functional groups, particularly amine ($C-NH_2$) groups on the GO surfaces. The highest tensile and impact strength values were 42.1 MPa and 12.3 J/m, respectively, which were observed in an epoxy composite prepared with GO treated with a 28% ammonia solution. This improved tensile strength was 2.2 and 1.3 times higher than those of the neat epoxy and the non-treated GO-based epoxy composite, respectively. The amine groups on the GO ensure its participation in the cross-linking reaction of the epoxy resin under amine curing agent condition and enhance its interfacial bonding with the epoxy resin.

• Journal of Aquaculture
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• 제10권4호
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• pp.435-438
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• 1997

Biological ammonia removal system have been used conventionally for the seawater fish farming. But this process requires long hydraulic retention times and large area. Also it has a trouble of NO3-N accumulation in the system. Therefore, this study was conducted to find out the feasibility of effective nitrogen removal efficiency in the sea water fish farming system by electolysis. As the result, electrolysis system showed a good ammonia and nitrate nitrogen removal and E. coli sterilization efficiencies. Because of the high salinities in the seawater for electron transfer, electrolysis is an effictive water treatment process for seawater fish farming. The relation among ammonia removal efficiency, hydraulic retention time (HRT) and electric wattage (watt) with 10 mm electrod distance isas follow ; log [$NH_4^$+-N(%)]=0.431log(HRT(sec)$\times$Watt)+0.88(r=0.950) And the relation between ammonia removal efficiency and residual chlorine concentration in the seawater is as follow; $$NH_4^+-N(%)=48\cdotlog[Residual\;chlorine(mg/\ell)+28(r=0.892)$$

• Korean Journal of Environmental Agriculture
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• 제40권4호
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• pp.366-372
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• 2021

BACKGROUND: Ammonia is known as a precursor to fine particulate matter, and according to CAPSS, annual ammonia emissions in the agricultural sector were 249,777 tons as of 2018, accounting for about 79.0% of Korea's total ammonia emissions. In particular, ammonia emissions from agricultural land increased by 19,566 tons (10.2%) compared to the previous year. The Ministry of Environment is setting emission statistics using the ammonia emission coefficient developed in Korea in 2008, but researchers in the agricultural field regard it as a coefficient that does not reflect the reality of Korea's agricultural environment. Accordingly, in order to develop ammonia emission coefficients from the cultivation of apples and pears, Korea's representative fruit type, test agricultural land was set in Iksan, Jeollabuk-do. METHODS AND RESULTS: This study attempted to obtain the ammonia emission coefficient by the treatment of the composite fertilizer (N-P₂O₅-K₂O=12-7-9), and the flux was measured using a dynamic flow-through chamber method. As for the chamber, a total of 12 chambers were installed repeatedly in 4 zones and used to develop emission coefficients. Using compound fertilizers during fruit tree cultivation, the ammonia emission coefficient was evaluated as 10.4 kg NH3/ton for pears and 15.3 kg NH₃/ton for apples. The reason why the ammonia emission coefficient according to the use of composite fertilizers was calculated higher for apple cultivation is believed to be due to the relatively high pH concentration of apple orchard soil. CONCLUSION(S): This study may provide basic data for upgrading the ammonia emission coefficient when using composite fertilizers in agricultural land. In the future, it might be necessary to upgrade the calculation of emissions through the development of ammonia and fine particulate matter emission coefficients considering the agricultural environment of Korea.

• Applied Biological Chemistry
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• 제27권
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• pp.18-28
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• 1984

In order to improve feed values of Korean agricultural by-products, various treatments including physical, chemical, physicochemical and fermentation were suggested in th is review article. Physical treatments such as chopping, grinding and pelleting reduce partiole size of agricultural by-products, and increase passage rate from the rumen, thus may increase voluntary feed intake and weight gain. Digestibility and voluntary feed intake of straw, rice hull and sawdust, also, may be increased by chemical treatment using sodium hydroxide or ammonia. Especially, because nitrogen content of by-products increase and toxic problem is not posed by ammonia treatment, it's practical usage is recommended in Korea. Silage or fermentation treatment using principles of microbial fermentation may improve palatability of low quality by-products. As mentioned above, it is concluded that various treatments suggested are desirable and improve feed value but may raise several problems. Unfortunately, because cost for installation and products is great and processing work is complicate, farmers are not using well these processing methods until now. Therefore, in order to increase the practical usage at farm level, it is thought that many research works be achieved for efficient process which have simple operation and low installation cost.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.566-567
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• 2009

We have examined the silicon nitride ($SiN_x$) as gate insulator with the ammonia ($NH_3$) plamsa treatment for the soluble derivatives of polythiophene as p-type channel materials of organic thin film transistors (OTFTs). Fabrications of the jetting-processed OTFTs with $SiN_x$ as gate insulator by $NH_3$ plasma treatment can be similar to performance of OTFTs with silicon dioxide ($SiO_2$) insulator.

• Reproductive and Developmental Biology
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• 제29권1호
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• pp.31-36
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• 2005

The purpose of this study was an improvement of efficiency and quality in the production of Korean Native Cow embryos. We investigated effects of concentration of ammonia in in vitro maturation (IVM) medium. In addition, we examined effects of addition or exchange of IVM medium on subsequent development and the cell numbers of blastocysts. The concentrations of ammonia in IVM medium was significantly increased by the increasement of IVM duration (p<0.05). The development rates to the 2 cell-, 8 cell- and blastocyst-stage embryos with the addition of IVM medium were similar among treatment groups. The number of inner cell mass (ICM) cells and the total cell number (TCN) of blastocysts were not differ among treatment groups, whereas the trophectoderm (TE) cell number was significantly lower in the group of 4.5 h addition. The ICM/TCN ratio was significantly higher in the group of 4.5 h addition than in the group of control and 9 h addition. The development rate to the 2-cell embryo with the exchange of IVM medium was significantly higher in the group of 4.5 h exchange and 9 h exchange than in control. The development rate to the blastocyst stage was the highest in the group of 9 h exchange. The number of ICM and ICM/TCN ratio were significantly higher in the group of 9 h exchange than the other groups. The numbers of TE and TCN was similar among treatment groups.

• Journal of Korean Society of Environmental Engineers
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• 제22권1호
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• pp.103-111
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• 2000

Ozonation and advanced oxidation($H_2O_2/O_3$) process were investigated under various experimental conditions to improve the efficiency of biological filter used for the treatment of recycled wastewater from aquaculture. Ammonia removal followed the first-order reaction whose reaction rate constant(k) was $2.0{\times}10^{-2}min^{-1}$ in ozonation. The ammonia removal rate increased according as the bicarbonate alkalinity is increased. About 46% $NH_3$ was oxidized by ozone at 200 mg/L as $CaCO_3$. When alkalinity existed in wastewater, ammonia removal rate by advanced oxidation was very low due to the inhibition effect of bicarbonate. However, when initial pH was adjusted to about 8.2 by 0.1 N KOH, ammonia removal rate was improved higher than that by ozonation. Especially. ammonia removal rate was the highest at $H_2O_2/O_3$ of 0.25 and about 90% of ammonia was removed in 30 min at this ratio as pH was maintained over 9. In the case of wastewater containing ammonia and organic constituents, ammonia removal efficiency by both ozonation and advanced oxidation decreased seriously because organic constituents consumed the oxidant faster than ammonia. In addition the optimal $H_2O_2/O_3$ ratio was changed. Like ammonia removal, DOC(dissolved organic carbon) increased for first 10 min and then decreased slowly because the particulate organic constituents were oxidized rapidly and then produce DOC. Even when the ammonia concentration by twice, oxidation of DOC was not retarded.

• Resources Recycling
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• 제32권6호
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• pp.45-53
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• 2023

This study discussed the trend and future strategy of adsorption technology R&D to effectively recover ammonia emitted from the livestock fields. A proper ammonia adsorbent should incorporate acidic or hydrogen bonding functional groups on the surface, as well as a high specific surface area and a good surface structure appropriate for ammonia adsorption. Activated carbon and minerals such as zeolite have widely been used as ammonia adsorbents, but their adsorption effects are generally low, so any improvement through surface modification should be necessary. For example, incorporation of metal chloride included in a porous adsorbent can promote ammonia adsorption effectiveness. Recently, new types of adsorbents such as MOFs (Metal-Organic Frameworks) and POPs (Porous Organic Polymers) have been developed and utilized. They have shown very high ammonia adsorption capacity because of adjustable and high specific surface area and porosity. In addition, Prussian Blue exhibited high ammonia adsorption and desorption performance and selectivity. This looks relatively advantageous in relation to the recovery of ammonia from livestock waste discharge. In the future, further research should be made to evaluate ammonia adsorption/desorption efficiency and purity using various adsorbents under conditions suitable for livestock sites. Also, effective pre- and/or post-treatment processes should be integrated to maximize ammonia recovery.