• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1606-1613
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• 2015

This study was carried out to investigate the effects of Yerba Mate (YM) supplementation on nutrients' degradation, in vitro dry matter disappearance, gas production and rumen ammonia concentration. Three rumen-fistulated Holstein Friesian cows were used for the in situ incubations and provided rumen liquor for in vitro incubations. The inclusion of YM in a control diet (pasture+pellets) affected some in sacco degradation parameters. YM supplementation decreased the effective degradability and degradation rate of pasture crude protein (CP), and it seems to slow down the degradation of pasture neutral detergent fiber. A significant increase of degradation of pasture acid detergent fiber (ADF) was detected after YM inclusion in the control diet. YM supplementation reduced in vitro gas production of pasture and ammonia concentration of pellets. The addition of YM in ruminant diet could decrease ammonia production and increase protein availability for productive purposes. The moderate presence of tannins in YM could have affected the degradation kinetics of pasture CP and ADF and the ammonia production of pellets.

• 한국환경농학회지
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• 제28권3호
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• pp.233-237
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• 2009

It has widely been observed that the effect of elevating atmospheric $CO_2$ concentrations on rice productivity depends largely on soil N availabilities. However, the responses of ammonia volatilization from flooded paddy soil that is an important pathway of N loss and thus affecting fertilizer N availability to concomitant increases in atmospheric $CO_2$ and temperature has rarely been studied. In this paper, we first report the interactive effect of elevated $CO_2$ and temperature on ammonia volatilization from rice paddy soils applied with urea. Urea labeled with $^{15}N$ was used to quantitatively estimate the contribution of applied urea-N to total ammonia volatilization. This study was conducted using Temperature Gradient Chambers (TGCs) with two $CO_2$ levels [ambient $CO_2$ (AC), 383 ppmv and elevated $CO_2$ (EC), 645 ppmv] as whole-plot treatment (main treatment) and two temperature levels [ambient temperature (AT), $25.7^{\circ}C$ and elevated temperature (ET), $27.8^{\circ}C$] as split-plot treatments (sub-treatment) with triplicates. Elevated temperature increased ammonia volatilization probably due to a shift of chemical equilibrium toward $NH_3$ production via enhanced hydrolysis of urea to $NH_3$ of which rate is dependent on temperature. Meanwhile, elevated $CO_2$ decreased ammonia volatilization and that could be attributed to increased rhizosphere biomass that assimilates $NH_4^+$ otherwise being lost via volatilization. Such opposite effects of elevated temperature and $CO_2$ resulted in the accumulated amount of ammonia volatilization in the order of ACET>ACAT>ECET>ECAT. The pattern of ammonia volatilization from applied urea-$^{15}N$ as affected by treatments was very similar to that of total ammonia volatilization. Our results suggest that elevated $CO_2$ has the potential to decrease ammonia volatilization from paddy soils applied with urea, but the effect could partially be offset when air temperature rises concomitantly.

• Asian-Australasian Journal of Animal Sciences
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• 제4권1호
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• pp.47-57
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• 1991

Supplementation of iodine at the level of 3.5mg/kg reduced weight gain of the rats fed rapeseed oil meal (ROM) diets. Treatment of ROM with ammonia at the level of 2 or 4% tended to increase metabolizable energy value and availability of dry matter, crude protein and crude ash of ROM in the chicken. Potential goitrin level of ROM was reduced by ammoniation at 6% level, while the level of potential isothiocyanates was increased by ammoniation. Treatment of ROM with ammonia at the level of 3% and above reduced weight gain of the chickens fed treated ROMs. Weight of thyroid glands of the birds increased as the level of ammoniation of ROM increased. Supplementation of Avoparcin to the diets containing ROM improved weight gain and dressing percentage of the broiler chickens.

• 한국대기환경학회지
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• 제20권6호
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• pp.729-738
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• 2004

Seasonal variation of major inorganic ions in the greater Seoul area was estimated using a photochemical box model and a gas/aerosol equilibrium model with emphasis on semi -volatile nitrate. Pollutant emission was determined by season by comparing the predicted concentration with the measurement one obtained for a year from the late 1996. The results showed that particulate nitrate was the highest in summer but about 40% of total nitrate was present in the gas phase. This was due to volatilization at high temperature since ammonia was sufficient to neutralize all nitrate regardless of season. As relative humidity in summer was higher than the deliquescence point, particulate ion concentration with water was two times higher than that in other season. So called ‘NOx disbenefit’ indicating increase in particulate ion concentration with decrease in NOx emission was evident especially in winter.

• 한국물환경학회지
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• 제22권3호
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• pp.540-545
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• 2006

The anaerobic digester supernatant (ADS) with high $NH_4-N$ concentration often results in a $NH_4-N$ overloading to the mainstream process of municipal wastewater treatment plant (MWTP). The nitrogen removal from the ADS is therefore important in order to achieve a stable mainstream process performance as well as to prevent $NH_4-N$ overloading due to ADS. Recently because of several advantages compared to the full nitrification, many works have shown interests in controlling the build-up of $NO_2-N$ in nitritation processes. The application of nitritation could save the aeration power compared to the full nitrification processes. In addition, the denitrification of $NO_2-N$ could reduce organic carbon requirements compared to the $NO_3-N$ denitrification. The purpose of this research was to find out the characteristics of the ADS nitritation and $NO_2-N$ accumulating factors from the laboratory reactor study. As a result based on the long-term laboratory experiment, it can be concluded that the degree of nitritation was closely related with the availability of alkalinity, free ammonia (FA), solid retention time (SRT) and solid concentration in the nitritation reactor.

• The Korean Journal of Ecology
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• 제8권1호
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• pp.21-29
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• 1985

The physico-chemical properties of sediment, the species composition and biomass of benthic diatoms were investigated in the intertidal zone of Kum river estuary, from July 1983 to May 1984. Sandflat sediment was more oligotrophic than mudflat one. The diatom composition was primarily associated with sediment grain size. The dominant epipelic diatoms belonged to the centric diatoms such as Paralia sulcata and Thalassiosira spp., while the epipsammic diatoms consisted mainly of Achnanthes haukiana and Amphora sabyii. Diatom flora of sandflat was more significantly diverse than that of mudflat. Mean yearly crop of sandflat diatoms was 2.8 times greater than that of mudflat diatoms and peaked at March reflecting the greater availability of ammonia.

• 한국대기환경학회지
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• 제23권1호
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• pp.74-83
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• 2007

Artifacts due to inter-particle and gas-particle interactions during PM2.5 sampling were quantified by comparing the measurement results between the annular denuder-filterpack system and the filterpack system without denuder. Measurements were carried in Seoul for 10 days in each season; Nov. 2004, Jan. 2005, Mar. 2005, and Jul. 2005, respectively. In each day, two 12-h samples were obtained. The concentrations of nitrate and chloride showed seasonal variations mainly due to the availability of ammonium to neutralize nitrate or chloride. Nitrates and chloride losses were prominent in summer. Since most of ammonia was used to neutralize sulfuric acid and formed ammonium sulfate in summer, nitrate and chloride could not exist in particles and ammonium loss was smaller than other seasons.

• 한국물환경학회지
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• 제32권4호
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• pp.343-348
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• 2016

A chemical sequencing batch reactor was operated to test the feasibility of nutrient recovery from a biological livestock wastewater treatment plant. Both phosphate and ammonia could be successfully recovered as magnesium ammonium phosphate (MAP) crystals. The contents of TP and TN in the recovered MAP crystals were 26.2% and 4.0%, respectively. Zn, Cr and Ti were identified in the crystals, but the contents remained below the Korean standard for an organic fertilizer. Chemical analyses confirmed that the MAP crystals could be useful phosphate fertilizers. On the other hand, the results of physical analyses using an X-ray diffractometer and an energy dispersive X-ray spectrometer strongly suggested that crystalline materials like magnesium potassium phosphate (KMP) and hydroxyapatite (HAP) were also formed during the MAP crystallization, depending on the availability of K⁺ and Ca²⁺.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.18-18
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• 2002

Nitrogenase, comprised of the MoFe and Fe proteins, catalyzes the reduction of dinitrogen to ammonia at ambient temperature and pressure. The MoFe protein contains two metal centers, the P-cluster (Fe8S7-8) and the FeMo-cofactor (Fe7S9：homocitrate), the substrate binding site. Despite the availability of the crystal structure of the MoFe protein, suprisingly little is known about the molecular details of catalysis at the active site, and no small-molecule substrate or inhibitor had ever been shown to directly interact with a protein-bound cluster of the functioning enzyme, until our electron-nuclear double resonance(ENDOR) study of CO-inhibited nitrogenase.(omitted)

• 한국토양비료학회지
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• 제12권2호
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• pp.91-97
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• 1979

1. 인삼(人蔘)의 유기질비료(有機質肥料)(약토류, 낙엽류(落葉類), 골분(骨粉)) 질소성분(成分)을 그 용해성(溶解性), 형태(形態) 및 함량(含量)에 따라 분석(分析)함으로서 질소성분(成分)의 성상과 유효성에 대해 밝히고자 하였다. 2. 용해성(溶解性)(수용성(水溶性), 플빅산(酸)과 부식산(腐植酸)의 산가수분해성(酸加水分解性), 가성(苛性)소다액(液) 추출성(抽出性))에 따른 질소성분(成分)의 분별결과(分別結果)는 다음과 같다. 약토류는 휴민태(態)>산가수분해(酸加水分解)>비가수분해성(非加水分解性)>수용성(水溶性), 낙엽류(落葉類)는 산가수분해성(酸加水分解性)>휴민태(態)>수용성(水溶性)${\geq}$산비가수분해성(酸非加水分解性), 골분(骨粉)은 산가수분해성(酸加水分解性)${\gg}$수용성(水溶性)>산비가수분해성(酸非加水分解性)의 순(順)이었다. 3. 수용성(水溶性)질소의 형태분석(形態分析)은 약토류와 낙엽(落葉)경우 부식태(腐植態)>아미노태(態)>초산태(硝酸態)(약토류만)>암모니아태(態)>Hexosamine태(態)>아마이드태(態). 골분(骨粉)은 아미노태(態) 부식태(腐植態)>암모니아태(態)${\geq}$아마이드태(態)의 순(順)이었다. 산가수분해성(酸加水分解性)질소 경우, 아미노태(態)>부식태(腐植態)${\simeq}$암모니아태(態)>Hexosamine태(態)의 순(順)이었다. 4. 질소의 용해성별(溶解性別) 및 주요형태(主要形態)(아미노태(態), 부식태(腐植態) 무기태(無機態))의 유효성에 대해 고찰(考察)하였다.