• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.483-489
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• 2014

This study aimed at a scientific examination of the relationship between NVOCs concentration and the physical environment of red pine forest in spring season. Atmospheric NVOC samples in red pine forest was collected through five trials conducted from March to May 2013, using Tanax-Ta-charged disposable tubes and mini-pumps. At each trial, measurements were taken at three different points in daytime (sunrise, southing and sunset). For maximum accuracy, two tubes were used for each measurement at the same location, and the mean value was used for analysis. Compound analysis on the NVOC samples was done using the HS-SPME method and GC-MS. Analysis of the relationship between NVOC and the physical forest environment found higher concentrations of most substances, including ${\alpha}$-pinene and ${\beta}$-pinene, with higher temperature, dew point, and lower concentrations with higher wind velocity. The findings of this study offer scientific evidence which can inform the creation of 'healing forests' and 'recreational forests' as well as forest environment in general, helping to promote public health and recreational activities.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.57-57
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• 2019

본 연구는 관상 및 조경용으로 개발이 가능한 남방계 양치식물인 점고사리[Hypolepis punctata (Thunb.) Mett.]의 전엽체 증식 및 포자체 형성에 적합한 배양조건을 구명하고자 수행되었다. 무가온 온실에서 성숙한 포자엽을 채집한 후 포자를 기내에서 발아시켜 전엽체를 획득하였으며, 8주 간격으로 계대배양 하여 실험의 재료로 사용하였다. 배지종류에 따른 전엽체의 증식 및 형태형성을 확인하고자, 배양된 전엽체 0.3g을 메스로 잘게 다진 후, 농도를 1/4, 1/2, 1, 2배로 조절한 MS배지에 8주간 배양하였다. 이후 선발된 배지를 기준으로 sucrose, 활성탄, 질소급원의 농도를 조절하여 전엽체의 증식과 형태형성을 확인하였다. 그 결과, 1MS배지에서 전엽체의 생체중이 초기 접종량인 0.3g에 비해 10.7배 증가한 3.2g으로 가장 높은 증가율을 보였다. 형태관찰에서도 장정기의 형성이 관찰되었으며, 전엽체의 쿠션조직이 비교적 잘 발달하였다. 전엽체 증식에 가장 좋은 효과를 보인 1MS배지를 기준으로 sucrose의 농도를 0-4%로 달리하여 실험한 결과, 1%의 처리구에서 6.7g으로 가장 높은 생체중을 보였다. 활성탄의 농도를 0-0.8%로 첨가한 네 처리구 중에서는 0.8%의 처리구에서 14.2g으로 무처리구에 비해 생체중이 2배 이상 증가하였다. 전엽체의 형태 또한 정상적인 발달을 보였다. 질소급원의 비율을 30-120mM로 조절한 배지에서는 60mM의 처리구에서 4.9g으로 가장 높은 생체중을보였다. 이후 포자체 형성을 위한 최적의 토양조건을 구명하고자, 원예상토, 피트모스, 펄라이트 및 마사토의 비율을 달리하여 5종류의 배양토를 조성하였다. 혼합된 토양은 사각분($7.5{\times}7.5{\times}7.5cm$)에 충진 하였으며, 배양된 전엽체 1g을 증류수와 함께 10초간 분쇄한 다음 준비된 토양표면에 분주하여 재배하였다. 12주간의 재배 결과, 원예상토를 단용한 토양에서 포자체의 수가 포트당 250.0개로 가장 많이 형성되었으며, 포자체의 생육 또한 다른 처리구에 비해 우수한 결과를 보였다. 한편 피트모스가 혼합된 토양에서는 포자체가 형성되지 않았다. 따라서 점고사리의 전엽체 대량증식에 적합한 배지는 sucrose 1%와 질소급원의 농도를 60mM, 활성탄을 0.8% 첨가한 1MS배지로 판단되며, 포자체 대량생산을 위해서는 원예상토를 단용한 토양이 적합하다고 판단된다.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.112-118
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• 1984

Inverase was entrapped in calcium alginate gel. The immobilized beads had excellent uniform size and configuration. To screen the optimal conditions possessing high enzyme activity, effects of sodium alginate concentration, $CaCl_2$ concentration, and the incubation time of beads in $CaCl_2$ solution during the immobilization procedure were investigated. Immobilized beads prepared from the optimal conditions had 18.8 units per ml of gel, which is equivalent to 68% of the activity of soluble enzyme. Several kinetic parameters were determined: Km value. 143 mM; optimum pH, 4.5; optimum temperature, $50^{\circ}C$. Enzyme loading capacity was 150 mg per 20 ml gel. No significant decrease in sugar conversion was observed during the column operation for 6 days.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.3-15
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• 1999

This paper includes the basic experimental results performed for developing an innovative and technologically feasible process wherein gaseous ozone, a powerful oxidant. is injected directly into vadose zone by which in-situ chemical degradation of semi- or, non-volatile petroleum product such as diesel fuel is derived. As ozone gas injected continuously(50mL/min, 119.0$\pm$6.1mg/L) into soil packed columns artificially contaminated with diesel fuel(initial concentration 1,485mg-DRO/kg/soil), the removal rates at the inlet and outlet point of 14hrs-operated column are 87.9% and 100.0%, respectively. On the other hand, soil vapor extraction system showed less than 30% of removal rates of residual diesel both at the inlet and outlet samples under the same experimental conditions which confirms the limited treatability of SVE in diesel contaminated soil.

• Journal of Energy Engineering
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• v.6 no.2
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• pp.203-211
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• 1997

This study is on the separation of Global warming effect gas, CO$_2$by chemical absorption from mixture of CO$_2$-N$_2$which was modeled after flue gas of fire power plant. Investigation of optimum condition for absorbent was carried out by using sparged vessel apparatus. Through packed tower experiments, applicabilities of two absorption models were tested by comparing experimental results with theoretical values. Absorbent used in the experiments was Monoethanolamine (MEA) and gas mixture was made in the mole composition of 15% CO$_2$and 85% N$_2$. Through estimations of CO$_2$loading and CO$_2$removal efficiency, optimum concentration of absorbent was found in the range of 4-5 M. To find a rate of absorption, an enhancement factor was introduced. Values of rate of absorption were calculated by Film model and Higbie model, respectively. Higbie model showed good agreement with experimental results. Therefore, this models is considered to be applicable to the CO$_2$separation process for flue gas from fire power plant.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.7
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• pp.58-64
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• 2006

Recently deep interests have been paid on the effective generation of ozone, which has been widely used for water treatment, deodorization, color removal, and chemical processing of exhausted smoke. The silent discharge reaction has been proposed as the most effective one in the many ozone generation methods, because the silent discharge can be generated under the conditions of lower applied voltage and power consumption, compared other ones. In this paper, in order to improve the ozone generation and ozone generation efficiency, the conventional silent discharge chamber with $Al_2O_3$ dielectric layer and tubular ferroelectric bed discharge reactor packed with $Al_2O_3$ pellets were made, and the silent discharge of the reactors were studied experimentally. The ozone generation characteristics are also discussed based on the discharge characteristics, especially on the wall charge accumulation properties and power consumption. The results show that the electric charges of discharge tube with bead are around 2.5 times as large as those without bead. In the discharge chamber packed with dielectric beads, the ozone concentration and the energy yield characteristics were also improved, compared with those in the conventional silent discharge reactor.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.115-125
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• 1998

The biodegradation of ($C^{14}$)phenanthrene was studied in water and soil-water systems with nonionic surfactants and biosurfactant : polyoxyethylene alkyl ester($C_{17}$$H_33$COO($C_2$$H_4$O)nH) and sophorolipid. The extents of so1ubilization and biodegradation were monitored by radiotracer technique. Experimental results showed that surfactant concentrations above the critical micelle concentration were toxic to the phenanthrene-degrading bacteria in soil or active sludge and the presence of surfactant micelles inhibited mineralization of PAHs. Solubility and bioavailibility of phenanthrene in water and soil-water system were enhanced by mixed surfactants system. The optimum water content and hydrogen concentration were 30% (w/v) , pH 7, respectively.

• KSBB Journal
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• v.21 no.1 s.96
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• pp.28-33
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• 2006

A sewage was treated using a horizontal flow zeolite-filled reed bed. The sewage from the student dormitory of Changwon National University was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^2$ day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolite : $0.5{\sim}1mm$ and $1{\sim}3mm$ in diameter. Annual average removal efficiency was SS $88.5%,\;COD_{cr},\;86.1%,\;COD_{Mn}\;81.0%,\;T-N\;48.6%,\;NH_4^+-N\;97.1%$ and T-P 42.8%. T-N of effluent was mostly $NO_3^--N$ and the concentration of $NO_2^--N$ in effluent was lower than 0.1 mg/L. All removal efficiencies did not show a remarkable seasonal change.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.21-30
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• 1998

The purpose of this study is to assess contaminant transfer and environmental impacts to the surroundings by inadequate control of USTs. Several methodologies can be used to approach for the site assessment depending on the appearance of contaminants on the site and their types. In this case study, randomized and/or triangle matrix techniques were used. As a result, the composition of materials in tank station were appeared in several state. From 1 to 1.5m depth, the soil was composed of reclaimed soils. And 1.8-3.5m depth, silty sand was appeared and about 4m, weathered soil was appeared. Based on the preliminary and actual site investigation by DPT methodologies on the width and depth of the site with analysis of BTEX and TPH, the contamination was found in this tank station and already distributed near areas. Finally, it was found that the hydroflow differences during the season affects the area and depth of contamination.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.167-177
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• 2011

Billions of barrels of briny produced water are generated in the United States every year during oil and gas production. The first step toward recovering or reusing this water is to remove the hazardous organics dissolved in the briny produced water. Biological degradation of hazardous volatile compound could be possible regardless of salinity if they were extracted from briny water. In the current work, the effectiveness of a vapor phase biofilter to degrade the gas-phase contaminants (benzene, toluene, ethylbenzene and xylenes, BTEX) extracted from briny produced water was evaluated. The performance of biofilter system responded well to short periods when the BTEX feed to the biofilter was discontinued. To challenge the system further, the biofilter was subjected to periodic spikes in inlet BTEX concentration as would be expected when it is coupled to a Surfactant-Modified Zeolite (SMZ) bed. Results of these experiments indicate that although the BTEX removal efficiency declined under these conditions, it stabilized at 75% overall removal even when the biofilter was provided with BTEX-contaminated air only 8 hours out of every 24 hours. Benzene removal was found to be the most sensitive to time varying loading conditions. A passive, granular activated carbon bed was effective at attenuating and normalizing the peak BTEX loadings during SMZ regeneration over a range of VOC loads. Field testing of a SMZ bed coupled with an activated carbon buffering/biofilter column verified that this system could be used to remove and ultimately biodegrade the dissolved BTEX constituents in briny produced water.