• Clean Technology
• /
• v.21 no.1
• /
• pp.33-38
• /
• 2015

In this research, life cycle inventory database (LCI DB) was developed for liquid CO₂ employing life cycle assessment (LCA) methodology. As are result of characterization and normalization process, production of liquid CO₂ puts on environmental impact in the order of resource depletion, global warming, acidification, eutrophication and photochemical oxidation, and among a wide variety of input, electricity contributes in most of the impact categories. Air emission plays a key role in the acidification and eutrophication while ammonia affects most on the ozone depletion. It is anticipated that development of liquid CO₂ LCI DB makes it possible for national environmental strategies to be more activated including environmental labeling scheme.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.35 no.11
• /
• pp.1297-1308
• /
• 2011

This research investigates the application of ZnO (zinc oxide) nanoparticles and $TiO_2$ (titanium dioxide) nanoparticles to polypropylene nonwoven fabrics via an electrospinning technique for the development of textile materials that can decompose harmful gases. To fabricate uniform ZnO nanocomposite fibers, two types of ZnO nanoparticles were applied. Colloidal $TiO_2$ nanoparticles were chosen to fabricate $TiO_2$ nano- composite fibers. ZnO/poly(vinyl alcohol) (PVA) and $TiO_2$/PVA nanocomposite fibers were electrospun under a variety of conditions that include various feed rates, electric voltages, and capillary diameters. The morphology of electrospun nanocomposite fibers was examined with a field-emission scanning electron micro- scope and a transmission electron microscope. Decomposition efficiency of gaseous materials (formaldehyde, ammonia, toluene, benzene, nitrogen dioxide, sulfur dioxide) by nanocomposite fiber webs with 3wt% nano-particles (ZnO or $TiO_2$) and 7$g/m^2$ web area density was assessed. This study shows that ZnO nanoparticles in colloid were more suitable for fabricating nanocomposite fibers in which nanoparticles are evenly dispersed than in powder. A heat treatment was applied to water-soluble PVA nanofiber webs in order to stabilize the electrospun nanocomposite fibrous structure against dissolution in water. ZnO/PVA and $TiO_2$/PVA nanofiber webs exhibited a range of degradation efficiency for different types of gases. For nitrogen dioxide, the degradation efficiency was 92.2% for ZnO nanocomposite fiber web and 87% for $TiO_2$ nanocomposite fiber web after 20 hours of UV light irradiation. The results indicate that ZnO/PVA and $TiO_2$/PVA nano- composite fiber webs have possible uses in functional textiles that can decompose harmful gases.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2003.11a
• /
• pp.123-124
• /
• 2003

6개의 화학제제를 육계의 깔짚에 첨가한 후 6주간의 사육기간 동안 육계의 생산성, 계사 내의 암모니아 발생량을 측정하여 6개의 화학제제를 대조구와 비교하였다. 본 실험은 A계사와 B계사 각각에 대조구(4케이지)와 시험구(4케이지)를 배치하였으며 대구대학교 동물사육실에서 실시하였다. 시험은 각 방에서 4반복으로 실시하였다. A계사는 화학제제 I (T$_1$)을 깔짚에 첨가하고 나머지는 대조구로 하였다. B계사에는 화학제제II(T$_2$)를 깔짚에 첨가하고 나머지는 대조구로 하였다. 대조구와 실험구는 철저히 막아서 공기가 서로 내통되지 않게 하였다. 화학제제 I (T$_1$)과 II(T$_2$)의 실험이 끝난 후 같은 방법으로 화학제제III(T3)과 IV(T4)도 실시하였으며 계속해서 화학제제V(T$_{5}$)와 Ⅵ(T$_{6}$)이 실시되었다. 총 시험기간은 2002년 10월 31일부터 익년 3월 22일까지 143일간 계속되었다. 6개의 화학제제를 각각 깔짚에 첨가하였을 때 대조구에 비교하여 육계의 생산성에는 아무런 차이가 없었다. 암모니아 가스 농도는 화학제제 I (T$_1$)과 II(T$_2$)의 경우 2주에서 6주까지 처리구와 대조구간의 차이를 나타내었다. 화학제제III(T$_3$)의 처리구는 5주 동안 암모니아 가스발생은 거의 없었으며 대조구와는 큰 차이를 나타냈다. 화학제제IV(T$_4$)와 V(T$_{5}$) 그리고 Ⅵ(T$_{6}$)에서도 처리구와 대조구간에 차이가 인정되었으나 처리IV(T$_4$)와 Ⅵ(T$_{6}$)의 경우는 처리구에서도 5주와 6주의 경우 암모니아 농도는 25 ppm이거나 그 이상을 유지하였다. 모든 처리구에서 계사내 암모니아 가스농도는 25 ppm보다 낮았으나 화학제제III(T$_3$)에서는 계사내의 암모니아 가스 발생량은 거의 0에 가까웠다. 결론적으로 6개의 처리들간의 비교는 할 수 없지만 화학제제III(T$_3$)의 경우에서 처리구는 암모니아 가스 발생량을 다른 처리구에 비교하여 가장 낮게 나타났다.

• Korean Journal of Organic Agriculture
• /
• v.10 no.4
• /
• pp.47-60
• /
• 2002

'Probiotics' as a live microbial feed supplementation which beneficially affects the host animal by improving its microbial balance and it is known to as a substitue for antibiotics in livestock feed industry. Lactic acid bacteria as a Lactobacillus sp. is formed acid and decrease pH in gastro-intestine that is result in suppress harmful microorganism. Lactobacillus sp. also produces vitamin and a variety amino acids. Yeast as a saccharomyces sp. secretes digestive enzymes, decreases ammonia emission and increases feed palatability by alcohol and glutamic acid. The effects of dietary probiotics in monogastric animals that improve weight gain and feed efficiency ratio and decrease diarrhea accurence frequency in pigs. Also, probiotics increase egg production ratio and beneficial microorganisms in laying hens. In broiler, they have more gain weight and lower blood cholesterol concentrations by probiotics. However, the other study reported probiotics supplementation in animal diets has no effect on ADG, G/F or performance. Thus, future study in these area will allow for more efficient use of the probiotics, selection of more superior microorganism and development of more efficient environment-friendly probiotics like a photosynthetic bacteria.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.3
• /
• pp.905-914
• /
• 2019

In this study, The PMF model was used to identify pollutant sources and their contribution to pollution sources of $PM_{2.5}$. The contribution of A city to each source was 19.8% for Secondary Sulfate, followed by Mobile 19.5%, Industry 16.0%, Biomass Buring 14.1%, Secondary Nitrate 14.1%, Oil Combustion 11.6%, Aged Sea Salt 2.6%, Soil 2.5% and so on. Sulfate and Ammonium concentrations were the highest contributing sources in the source profile, which was analyzed to be Secondary Aerosols produced by Photochemical Reactions of gaseous precursors (SOx and ammonia gas) in the atmosphere.

• Journal of the Korea Convergence Society
• /
• v.10 no.4
• /
• pp.131-138
• /
• 2019

Diesel engines have important advantages over its gasoline counterpart including high thermal efficiency, high fuel economy and low emissions of CO, HC and $CO_2$. However, NOx reducing is more difficult on diesel engines because of the high $O_2$ concentration in the exhaust, marking general three way catalytic converter ineffective. Two method available technologies for continuous NOx reduction onboard diesel engines are Urea-SCR and LNT. The implementation of the Urea-SCR systems in design engines have made it possible for 2.5l and over engines to meet the tightened NOx emission standard of Euro-6. In this study, we investigate the characteristics of NOx reduction with respect to engine speed, load, types of catalyst and the $NH_3$/NOx ratio and present the conditions which maximize NOx reduction. Also we provide detailed experimental data on Urea-SCR which can be used for the preparation for standards beyond Euro-6.

• Applied Chemistry for Engineering
• /
• v.32 no.3
• /
• pp.237-242
• /
• 2021

Simultaneous removal technologies of multi-pollutants such as particulate matters (PMs), NOx, SOx, VOCs and ammonia have received consistent attention due to the enhancement of pollutant abatement efficiency in addition to the stringent environmental regulation and emission standard. Pretreatment of insoluble NO by an ozone oxidation can be considered to be more effective route for saving space occupation as well as operation cost in comparison with that of traditional selective catalytic reduction (SCR) process. Moreover the primary advantage of ozone oxidation process is that the simultaneous removal with acidic gas including SOx is also available. Herein, we highlight recent studies of multi-pollutant abatement via ozone oxidation process and the promising research topics for better application in industrial sectors.

• Journal of Animal Environmental Science
• /
• v.16 no.2
• /
• pp.99-108
• /
• 2010

The principal objective of this study was to investigate the cooling effects of geothermal heat pump system (GHPS) in farrowing house. A total of 96 sows were allocated to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in summer season. During the experimental period of four weeks, the highest outside temperature observed was approximately $34.1^{\circ}C$, GHPS decrease indoor temperature of pig housing up to $30.9^{\circ}C$, but conventional pig housing was similar to outside temperature. Dust concentrations (maximum 61.4%) of particulate matter less than $10{\mu}m$ (PM 10) in GHPS-housing were lower than the conventional housing. GHPS showed no signigicant difference in carbon dioxide emission, whereas the ammonia gas concentration was significantly decreased in GHPS-housing compared to that of conventional housing. Sows in GHPS-housing showed significantly lower respiratory rate than those of the control group. GHPS did not affect hormone level, litter size and birth weight, but weaning weight of piglets was influenced by GHPS. Feed consumption of sows was significantly increased in GHPS-housing compared to the conventional hosing. These results suggest that GHPS decrease dust concentration, ammonia gas emission and indoor temperature of pig housing and may affect performance in sows and weaned piglets.

• Korean Journal of Poultry Science
• /
• v.48 no.3
• /
• pp.151-160
• /
• 2021

This study was conducted to determine the concentrations of particulate matter (PM) and NH3 emissions from different types of laying hens poultry houses during spring. The concentrations of PM and NH3 were measured three times (2-week intervals; March to May) in Floor-pen-, Aviary-, and Cage-type poultry houses. Overall, PM₁₀ and PM_2.5 concentrations were found to be low from 22:00 to 04:00. The PM₁₀ and PM_2.5 concentrations in Floor-pen and Cage houses were similar with no significant daily deviation. NH₃ concentrations measured over 24 h at the center and end of Floor-pen house were relatively constant. Irrespective of measurement location, NH₃ concentrations were the lowest in Floor-pen house. Moreover, NH₃ concentrations were higher at the end of Floor-pen and Aviary houses than that at the center; however, lower concentrations of NH₃ were detected at the end of Cage house. The concentrations of PM₁₀ and PM_2.5 around the poultry houses were 57.5 and 34.0 ㎍/m³, respectively, with the daily average PM₁₀ and PM_2.5 concentrations (4,730 and 447.7 ㎍/m³, respective) being the highest in Aviary house. The concentrations of NH₃ at the center and end of Cage house were the highest at 12.0 and 9.31 ppm, respectively. Furthermore, in Cage house, the emission factor of NH₃ was the lowest, whereas there was no significant difference on that of NH₃. In conclusion, among the three types of poultry houses assessed, PM (PM₁₀, PM_2.5) concentrations were higher in Aviary house, whereas NH3 concentrations were higher in Cage house.

• Korean Journal of Heritage: History & Science
• /
• v.56 no.2
• /
• pp.136-146
• /
• 2023

Biological materials, such as stuffed specimens, can release various acids or volatiles. There has been no research carried out on the emission characteristics of organic compounds generated from the preservatives used in taxidermy specimens or associated manufacturing materials and methods. Therefore, in order to identify the organic compounds generated from taxidermy specimens, a degradation experiment was conducted on specimens for each material and for storage specimens. To produce Ogye chicken specimens, naphthalene and borax were used as preservatives, and planer sawdust, newspaper, and polystyrene foam were used as the core body materials. The deterioration experiment was conducted for 2 weeks in a high-temperature environment(50℃) and a high-humidity environment (95%), with an Ogye chicken specimen (year 2015) kept in an animal storage facility. Results indicated that the concentration of organic compounds generated by the specimen in the high-temperature environment tended to be greater than that in the high-humidity environment. The preservatives benzene, toluene, xylene, and p-dichlorobenzene were detected in the specimens using naphthalene, confirming that naphthalene is a major organic compound release factor, and the specimens that used sawdust, newspaper, and polystyrene foam also exhibited organic compounds. This appears to have been due to degradation of the material. In addition, ammonia was detected in the specimens for each material due to decay. In particular, the specimens using borax at high temperature were subject to approximately 9 times higher rates of ammonia-related deterioration than the specimens using naphthalene. These results can be considered to result from the prevention of biological damage through insecticidal effects by accelerating the sublimation of naphthalene in a high-temperature environment. Naphthalene is a potentially carcinogenic substance, and when used as a preservative, proper use management is required. Taxidermy specimens can release various organic compounds depending on the manufacturing techniques used, so a systematic preservation management plan is required that depends on conditions such as the applicable manufacturing materials and preservatives.