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        검색결과 174

        85.
        2015.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to assess the efficacy of slurry acidification in reducing ammonia emission from manure storage and application. The non-fermented cattle manure (NFC) and swine slurry (SS) were acidified by sulfuric acid and stored in an acryl chamber for 168 and 96 hours, respectively. Ammonia emitted from the chamber was collected using an acid trap system. The amount of ammonia emission was significantly reduced when the livestock manures were treated with sulfuric acid. The absolute amount of ammonia in NFC increased rapidly starting from 48 h and 72 h in the control (pH 8.6) and acidified NFC (pH 6.5), respectively. The absolute amount of ammonia was the highest at 96 h (3.65 g kg ¯¹ h ¯¹) in the control and at 144 h (2.34 g kg ¯¹ h ¯¹) in pH 6.5 NFC. The cumulative ammonia content in the control continuously increased until 96 h and was maintained until 168 h, whereas the increase rate of emission gas accumulation in acidified NFC was much less throughout the experimental period. Acidification of SS mitigated ammonia emission as proven in NFC. The cumulative amount of ammonia emission was decreased by 49.4% and 92.3% in the acidified SS at pH 6.5 and pH 5.5, respectively, compared to the control at 96 h after treatment. These results indicate that ammonia emission can be significantly reduced by sulfuric acid treatment of livestock manure during processing and the subsequent land application.
        4,000원
        86.
        2015.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The experiment was performed using the cleaning precipitator To investigate the absorption efficiency of the SOX/NOX of the aqueous ammonia solution. Concentration of the cleaning liquid is 0.1, 0.5, and 1.0% with increasing absorption efficiency has improved. However, the reaction shown only a difference in time. Absorption efficiency has improved in accordance with the gas residence time. When the direction of the same gas and the cleaning liquid is determined that there is the effect of increasing the residence time. The relative impact of SOX and NOX is this likely to react slower than SOX/NOX. The yield is determined to require
        4,000원
        87.
        2015.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to improve the ammonia (NH3) emission inventory estimation in the domestic CAPSS (Clean Air Policy Support System). Currently, the ammonia emissions rate is obtained by multiplying the activity (number of livestock) by emission factors. The amount of movement and treatment are not considered in the estimation of ammonia emission rates. However, livestock manure is currently moved and treated in accordance with the energy recycling policy. In this study, the new emission estimation method were suggested considering the moving and treatment characteristics of livestock manure. A new ammonia emissions was calculated for Bcity and Y-gun at Chungcheongnam-do province. It was shown that the moving and treatment ratio of ammonia emissions were 4.3% and 8.4%, respectively. Furthermore, this ratio would be increased rapidly with the continuous establishment of large-scale manure treatment facilities.
        4,000원
        88.
        2015.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study provides a comparison and analysis of the predicted damages related to hazardous chemical substances used in “A” solar cell manufacturing process. In order to predict potential damages, different accident scenarios were established using the ALOHA model and the KOSHA guideline. This study evaluates chemical spills and leaks from cylinder and pipeline. Maximum distance of chemical movement, based on an initial concentration of 150 ppm, was estimated as up to 258 m in summer and 251 m in winter. The impacts of the leakage of chemicals such as ammonia, were dependent on the initial concentration of the chemical leaked, the atmospheric stability and temperature, and the wind speed. All of those however, were affected by air humidity.
        4,600원
        89.
        2015.06 구독 인증기관 무료, 개인회원 유료
        This study investigated the effects of LactoPlanta® (Lactobacillus plantarum (L. plantarum), 2.0 × 109 colony forming units (CFU)/kg) on reduction of noxious gas emission in pig houses as well as improvement of carcass weight and quality in finishing pigs. A total of 850 finishing pigs were assigned to four treatment groups: control (CON, basal diet) (n=190), LP-0.1, 0.1% LactoPlanta® (n=210), LP-0.2, 0.2% LactoPlanta® (n=230), and LP-0.4, 0.4% LactoPlanta® (n=220). Ammonia and hydrogen sulfide concentrations were significantly reduced in all treatment groups compared to CON. Mercaptan contents and carcass weights of LP-0.2 and LP-0.4 were significantly decreased compared to CON, whereas there were no significant differences between LP-0.1 and CON. Carcass weight of LP-0.1 was slightly higher than that of CON, but there was no significant difference. However, carcass weights of LP-0.2 and LP-0.4 were significantly higher than that of CON (P<0.05). The prevalence of grade A carcasses in groups administered with L. plantarum (46.7~63.3%) was higher than that in CON (43.3%) and increased in a dose-dependent manner. Based on the results of this study, L. plantarum could be an effective candidate to reduce noxious gas emissions in finishing pig houses as well as improve carcass weight and quality in finishing pigs.
        4,000원
        90.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        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±8.0 g) were exposed to five levels of un-ionized ammonia (NH3) (control, 1, 2, 4, 8 mg 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 8 mg L-1 NH3, which was significantly high compared to normal 1 mg L-1 NH3. Although ammonia exposure had no effect on plasma Cl-, exposure to both 4 and 8 mg L-1 NH3, 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 8 mg L-1 NH3 showed significantly higher hematocrit than control group than those exposed to 1 and 2 mg L-1 NH3. 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.
        4,000원
        92.
        2014.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It is essential to decrease energy consumption and excess sludge to economically operate sewage treatment plant. This becomes more important along with a ban on sea dumping and exhaustion of resource. Therefore, many researchers have been study on energy consumption reduction and strategies for minimization of excess sludge production from the activated sludge process. The aeration cost account for a high proportion of maintenance cost because sufficient air is necessary to keep nitrifying bacteria activity of which the oxygen affinity is inferior to that of heterotrophic bacteria. Also, additional costs are incurred to stabilize excess sludge and decrease the volume of sludge. There were anoxic, aerobic, membrane, deairation and concentration zone in this MBR process. Continuous aeration was provided to prevent membrane fouling in membrane zone and intermittent aeration was provided in aerobic zone through ammonia sensor. So, there was the minimum oxygen to remove NH4-N below limited quantity that could be eliminated in membrane zone. As the result of this control, energy consumption of aeration system declined by between 10.4 % and 19.1 %. Besides, we could maintain high MLSS concentration in concentration zone and this induced the microorganisms to be in starved condition. Consequentially, the amount of excess sludge decrease by about 15 %.
        4,000원
        93.
        2014.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 국가단위 암모니아 인벤토리 작성을 위한 자료를 제공하기 위해 무창산란계사에서 사육되고 있는 Hy-line Brown 산란계를 대상으로 암모니아 휘산량을 조사하였다. 무창산란계사의 환기는 120 cm 직경의 배기팬 9대에 의해 이루어졌으며, 계분은 벨트로 매일 아침에 배출되었다. 온도, 암모니아 농도, 배기팬의 풍속 등은 계절별로 각각 3일동안 측정되었다. 무창산란계사에서의 암모니아 휘산량은 계절 간에 차이를 나타내지 않았으며, 연평균 무창산란계사 산란계의 암모니아 휘산량은 0.282 kg hd-1 yr-1로 나타났다.
        4,000원
        94.
        2014.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Ammonia is one of typical index substances of environmental odor. This study describes a rapid and simpleadsorption tube type detector to be able to measure the level of strict emission standards with quantitativeconcentration of gaseous ammonia as the regulations are enhanced. a gas detector tube can be measured theammonia gas concentration of 0.23ppm, 0.5ppm, 1ppm, 1.5ppm and 2ppm through the relation between theSampling rate Kog (=DA/L) and the discoloration reaction rate by physico-chemical analysis. Also this study canbe predicted the relation between the sampling volume and the sampling time. and it can be designed to measuringthe range of various concentrations. In this case study, an optimum design was found with an sampling rate, 42ml/min and with a tube diameter, 3.0mm. Adsorption and diffusion rate was evaluated by Fick's law.
        4,000원
        95.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 국가단위 암모니아 인벤토리 작성을 위한 자료를 제공하기 위해 한우와 육계를 대상으로 암모니아 휘산량을 조사하기 위해 실시되었다. 개방한우사의 계절별 암모니아 휘산량은 겨울철이 가장 낮았고, 봄, 여름, 가을 큰 차이를 보이지 않았다. 그리고 연평균 개방한우사 한우의 암모니아 휘산량은 7.605 kg hd-1 yr-1 로 평가되었다. 개방육계사의 계절별 암모니아 휘산량은 한우와 동일한 경향을 보였다. 연평균 개방육계사 육계의 암모니아 휘산량은 0.191 kg hd-1 yr-1로 평가되어 육계가 한우보다 높은 것으로 나타났다.
        4,000원
        96.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In order to improve the selective oxidation reaction of gaseous ammonia at a low temperature, various types of metal-impregnated activated alumina were prepared, and also physical and chemical properties of the conversion of ammonia were determined. Both types of metal (Cu, Ag) impregnated activated alumina show high conversion rate of ammonia at high temperature (over 300℃). However, at lower temperature (200 ℃), Ag-impregnated catalyst shows the highest conversion rate (93%). In addition, the effects of lattice oxygen of the developed catalyst was studied. Ce-impregnated catalyst showed higher conversion rate than commercial alumina, but also showed lower conversion rate than Ag-impregnated sample. Moreover, 5 vol.% of Ag activation under hydrogen shows the highest conversion rate result. Finally, through high conversion at low temperature, it was considered that the production of NO and NO2, toxic by-products, were effectively inhibited.
        4,000원
        97.
        2013.08 구독 인증기관 무료, 개인회원 유료
        The main objective of this work is to perform experimental analyses of a absorption refrigeration system using a new refrigerant-sorbent pair as the working pair. The active component of sorbent is sodium thiocyanate (NaSCN). Ammonia (NH3) is chosen as refrigerant. As a result of these, it is concluded that the unit exhibits good cooling performance and the average cooling capacity is approximately 28.8kW and the average coefficient of performance (COP) of absorption system is 0.56. The unit is a thermal compressor which uses low-grade waste heat to generate refrigeration (cooling or freezing).
        4,000원
        98.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Polypyrrole (PPy)/multi-walled carbon nanotubes (MWCNTs) composites were prepared by in situ polymerization of pyrrole on the surface of MWCNTs templates to improve the ammonia gas sensing properties. PPy morphologies, formed on the surface of MWCNTs, were investigated by field emission scanning electron microscopy. The thermal stabilities of the PPy/MWCNTs composites were improved as the content of MWCNTs increased due to the higher thermal stability of the MWCNTs. PPy/MWCNTs composites showed synergistic effects in improving the ammonia gas sensing properties, attributed to the combination of efficient electron transfer between PPy/MWCNTs composites and ammonia gas, and the reproducible electrical resistance variation on PPy during the gas sensing process.
        4,000원
        99.
        2012.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 강제환기가 적용되는 슬러리 돈사를 대상으로 돼지 생육 단계별 돈방 유형 측면과 계절적 조건에 따른 암모니아와 황화수소의 실내 농도를 측정 분석하여 정량화하는 데 있다. 임신/분만 돈방의 경우 봄철은 5.60(±2.48) ppm과 178.4(±204.8) ppb, 여름철은 2.51(±3.08) ppm과 86.6(±112.5) ppb, 가을철은 4.96(±2.84) ppm과 182.3(±242.6) ppb, 겨울철은 6.82(±3.42) ppm과 206.3(±356.8) ppb로, 자돈방의 경우 봄철은 7.18(±3.26) ppm과 486.0(±190.2) ppb, 여름철은 4.23(±2.95) ppm과 206.4(±186.9) ppb, 가을철은 7.02(±2.65) ppm과 465.4(±156.8) ppb, 겨울철 은 9.25(±3.68) ppm과 618.4(±298.3) ppb로, 육성/비육 돈방의 경우 봄철은 9.26(±3.02) ppm과 604.4(±186.8) ppb, 여름철은 6.78(±3.88) ppm과 312.5(±215.4) ppb, 가을철은 9.34(±2.14) ppm과 578.2(±248.1) ppb, 겨울철은 14.65(±3.15) ppm과 825.3(±316.9) ppb로 분석되었다. 측정 결과 암모니아와 황화수소 모두 돼지 생육 단계별 돈사 유형 측면에서는 육성/비육 돈사>자돈사>임신/분만 돈사의 순서로 나타났고(p<0.05), 계절적 측면에서는 겨울>봄>가을>여름 순서로 조사되었으나 봄철과 가을철 데이터 간의 차이는 통계적으로 입증되지 않았다(p>0.05).
        4,000원
        100.
        2010.12 KCI 등재 구독 인증기관·개인회원 무료
        Addition of ammonia or any nitrogenous materials to the soil that release ammonia causing alkaline condition during decomposition stimulates the fruiting of a particular chemoecological group of fungi, called ammonia fungi (Sagara 1975). The study of ammonia fungi by artificial application of urea in forest soil has been done in diverse geographical regions such as in Japan, Taiwan, New Zealand, Western Australia, and UK. Up to date about 70 species of ammonia fungi have been recorded in those regions. However, ammonia fungi in the boreal forest of American continent have not yet been investigated. Thus, we collected the soils of A0 and the upper layer of HA horizons in plant pots from aspen forest near Edmonton, Canada. Thereafter, we applied urea (granular fertilizer; 46% nitrogen, 10 mg/g dry soil) in plant pots and incubated at 25˚C under 12 hours dark and light regime. After 40 days of incubation, several basidiomata of Coprinopsis species appeared. Among them one specimen was identified as C. rugosobispora based on macro- and microscopic features. Morphologically this species was very similar to C. phlyctidospora which was characterized by warty, ovoid basidiospores, and diverticulate veil elements. C. phlyctidospora has 4-spored basidia while C. rugosobispora had only 2-spored. In the beginning, it was thought probably it was only a 2-spored form of C. phlyctidospora. The basidiospore of C. rugosobispora (9.8-11.7×8.3-9.6㎛) was distinctly larger than that of C. phlyctidospora (8.4-10.6×6.0-7.6 ㎛). It was therefore separated from the C. phlyctidospora. Furthermore in this study we investigated its phylogenetic relationship based on the nuclear rDNA sequence in ITS regions and mating reactions among its close allies and further confirmed it as a distinct species. This is the first record of C. rugosobispora from American continent since it has been collected only from Europe (Belgium and Netherlands). Although urea effectively stimulated its occurrence but it has not yet been reported any other urea application studies so far. This indicates it is a new record in ammonia fungi as well.
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