• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.391-392
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• 2003

한전 원자력 환경기술원에서는 중ㆍ저준위 방사성폐기물 유리화 기술의 상용화 가능성을 입증하기 위한 유리화 실증설비를 건설하여 시험 중에 있으며 이 유리화 기술은 유도 가열식 저온로(Cold Crucible Melter, CCM)에 폐기물을 투입하는 기술로서 폐기물의 부피 축소 효과와 더불어 최종 고화물로 생성되는 폐기물의 침출율이 매우 낮은 장점을 지닌다. 이와 같은 유리화 공정은 기존의 소각처리에서와 같이 폐기물의 열적 산화과정에 의해 유해오염가스와 입자성 물질이 발생된다. 따라서 이를 처리하기 위해배기체 처리공정(Off Gas Treatment System, OGTS)을 설치하여 환경 배출기준(SO$_2$300ppm, NO$_2$ 200ppm, CO 600ppm, HCI 50ppm, 분진 100mg/Nm$^3$ 등)을 만족하도록 하였고 특히 입자성 물질은 후단 OGTS나 배관내 침적으로 인한 방사성 오염을 막기 위해 CCM 후단에서 효율적으로 제거되어야만 한다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.49-50
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• 1995

고분자분리막을 이용한 기체 혼합물의 분리방법은 심냉법(cryogenic process), 가압기체흡착법(Pressure adsorption)과 더불어 상업적으로 중요한 기체분리공정으로 부각되고 있다. 특히 고분자막 중 Polyimide 막은 열적, 화학적으로 안정하고 기체에 대한 선택성이 높으며 기계적 성질이 뛰어나 좋은 막소재로 알려져 있다. 그러나 투과도와 선택도사이에 일반적으로 Trade-off 현상이 있어서 투과도와 선택도를 동시에 향상 하려는 연구가 수행중에 있다. 본 연구에서는 높은 산소투과도를 갖는다고 보고된 6FDA-p-TeMPD막에 hexafluoropropene (HEP)으로 Plasma polymerization을 시키거나 CF$_4$, Ar기체가 플라즈마처리하여 투과특성을 개선시키고 이를 비교 고찰하였다.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.176-179
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• 2004

Volatile organic compounds (VOCs) are emitted as gases from certain solids or liquids. VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects. Current technologies for the treatment of VOC contaminated off-gasses are expensive to operate and more cost effective technologies are needed.(omitted)

• Journal of the Korean Ceramic Society
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• v.33 no.9
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• pp.1064-1072
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• 1996

The synthetic conditions and characteristics of ZSM-5 type zeolites (ZSM-5/silicalite) for the preparation of the zeolite composite membranes for gas separation were investigated. ZSM-5 zeolites could be synthesized by the hydrothermal treatment of the mixture of colloidal silica sol aluminum nitrate sodium hydroxide and TPABr at a temperature range of 150-17$0^{\circ}C$ in the autoclave. Silicalties were done from the solution of water glass water and TPABr. Their crystalline structures transformed from orthorhombic to monoclinic from and their pore structures of three-dimensional channels were opened as TPABr filling channels was burned off at the calcination temperature of 50$0^{\circ}C$. The specific surface area of the calcined zeolite was about 360 m3/g and its surface property was hydrophobic. Crystal sizes of ZSM-5 and silicalite were 0.5-1.0${\mu}{\textrm}{m}$ and 8-10${\mu}{\textrm}{m}$ respectively having no change due to the calcination. In particular the shape and the size of the ZSM-5 type zeolite were sensitively varied with silica sources and concentrations of reaction solutions/sols.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.246-249
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• 1994

Shelf-life of pork packaged under $CO_{2}$ was observed and the optimal volume of $CO_{2}$ gas was determined. High gas barrier film, EVOH($CO_{2}$ permiability; 1 $cc/cm^{2}{\cdot}24\;h{\cdot}atm$) was used as packaging material and the volume ratios of sample to $CO_{2}$ of 1 : 1, 1 : 3 and 1 : 5 were tried using the control of vacuum packaged pork. To ev.3luate quality of pork cuts, total plate counts, TBA, color and sensory score were monitored during the storage at $4{\pm}1^{\circ}C$ for 31 days. TPC of vacuum packaged pork increased up to $4.6{\times}10^{6}\;CFU/cm^{2}$ in 24 days while that of $CO_{2}$ gas packaged pork $4.5{\times}10^{5}\;CFU/cm^{2}$ at the same storage period, and it took 7 days more for gas packaged pork to reach the same TPC count. There was no significant difference in TBA value between vacuum packaged and gas packaged pork. In the color L and a values were not affected by treatment but vacuum packaged pork cuts showed higher b value than gas packaged pork. According to sensory evaluation, gas packaged pork showed less off flavor, better flavor and freshness than vacuum packaged one (P<0.05).

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.197-203
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• 2019

This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.58-65
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• 2010

AlN thin films were deposited on sapphire substrates and ZnO templates by rf-magnetron sputtering. Powder-sintered AlN target was adopted for source material. Thickness of AlN layer was linearly dependent on plasma power from 50 to 110 W, and it decreased slightly when working pressure increased from 3 to 10 mTorr due to short mean free path of source material sputtered from AlN target by Ar working gas. When $N_2$ gas was mixed with Ar, the thickness of AlN layer decreased significantly because of low sputter yield of nitrogen. AlN layer was also deposited on ZnO template. However, it showed weak thermal stability that the interface between AlN and ZnO was deteriorated by rapid thermal annealing treatment above $700^{\circ}C$. In addition, ZnO layer was largely attacked by MOCVD ambient gas of hydrogen and ammonia around $700^{\circ}C$ through inferior AlN layer deposited by sputtering. And AlN layers were fully peeled off above $900^{\circ}C$.

• Asian Journal of Turfgrass Science
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• v.21 no.2
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• pp.127-135
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• 2007

Korea and Japan hosted the FIFA World Cup Soccer Game in 2002. Ten stadiums had been built and more than 30 soccer grounds for practice were renovated in Korea. Sport fields in both countries had problems on cool-season turfgrass growth and quality by summer decline during humid and warm climate especially followed by intensive uses. We measured the effects of air-flow system, which is designed to optimize rootzone soil gas and moisture levels to promote the growth and maintenance turfgrass. This experiment was carried out to verify the effects of the system on soil gas exchange, ground resilience, and turfgrass recovery in turfgrass rootzone. Within 1 or 2hr of operation of the system, rootzone soil gas ($CO_2$, $O_2$) levels returned to natural atmospheric levels completely Soil $CO_2$ levels began to decrease within the first 10 min of operation of the system. The levels were reduced from 1.3 to 0.06% after 30 min, and natural atmospheric levels within 1 hr. When the system was turned off, $CO_2$ levels increased to 0.36% and 0.7% after 5 and 20 hr, respectively. The application of the system did not affect the resilience of turf surface after traffic treatments. Higher traffic treatment resulted in higher surface resilience especially in zoysiagrass plots. Operation of the system had a significant beneficial impact on turf recovery by increased root dry wight and improved turf quality, as compared with the non-operated check plots.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.3
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• pp.221-227
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• 2010

The solidification methods for powder wastes dried at CWDS(Concentrate Waste Drying System) in PWR have been studied in a variety of ways both at home and abroad. The solidification for these wastes has been performed using stabilization agents such as cement, paraffin and polymer. The applicability studies to maximize the reduction ratio of wastes and operational effectiveness for wastes treatment have been carried out, recently. It is necessary to pretreat the powder wastes before feeding wastes to vitrification facility because the fines flying brings about clogging of feeding pipes and off-gas treatment system or workers' exposure to radiation during maintenance. This paper describes an effective method for treatment of powder wastes to improve safety and stability of vitrification facilities.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.475-480
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• 2009

These studies were carried out to find the effect of packing materials and storage temperature to enhance the storability of Salicornia europaea. The fresh weight loss was less than 2% at below $10^{\circ}C$ and non-perforated package, but $25^{\circ}C$ and perforated package treatment showed more than 4% of fresh weight loss that result to deteriorate quality. The carbon dioxide and oxygen contents remained 1~2% and above 15% in non-perforated package, and these contents were in proportion to gas permeability of packing materials. All the temperature treatments except 25c showed rapidly increasing ethylene concent from 7days after storage, and the highest ethylene content was $2^{\circ}C$ treatment that should appear chilling injury. The off-odor and deterioration ratio were lowest in $5^{\circ}C$ among the temperature treatments and $50{\mu}m$ thickness ceramic film treatment at $5^{\circ}C$ storage, while packing materials did not show any trends among the temperature treatments. The shelf life based on visual quality showed highest in $50{\ss}|$ thickness ceramic film packing and $5^{\circ}C$ treatment, and that was 28days.