• KSBB Journal
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• v.15 no.2
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• pp.150-155
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• 2000

Antioxidative activity of c비ture of Streptomyces sp. BH-405 was investigated. After removal of pellets of Streptomyces sp. B BH-405, antioxidative substances were is미ated and suc$\infty$sively purified from culture of Streptomyces sp. BH-405 by by thin | layer chromatography $\pi$LC) or silica gel column chromatography. The fraction 3 obtained from ethylether fractionation of the C culture appeared highest level of anti oxidative activity as determined by thiocyanate method. Band 2 obtained by further P purification of this fraction showed higher anti oxidation level than that of same concentration of dl- $\alpha$ -tocopherol, butylated h hydroxy anisole (BHA). The band 2 showed higher rate of 1, 1.diphenyl 2-picrylhydrazyl (DPPH) decolorization than dl-$\alpha$-tocopherol. In the rat liver microsomes, band 2 rapidly inhibited lipid peroxidation which was initiated enzymatically by r reduced nicotinamide adenine dinucleotide phosphate (NADPH) or non-enzymatically by Fenton’s reagent. Band 2 inhibited on | lipid peroxidation of mitochondria or the linoleic acid hydro peroxide induced peroxidation system. It is concluded that band 2 obtained by fractionation of Streptomyces sp. BH-405 cultivation contained antioxidants with the capacity to inhibit oxidative m modification.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.13-20
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• 2011

The high fuel flexibility of Micro Gas Turbine(MGT) has boosted their use in a wide variety of applications. Recently, the demand for biogas generated from the digestion of organic wastes and landfill as a fuel for gas turbines has increased. We researched the influence of firing landfill gas(LFG) on the performance and operating characteristics of a micro gas turbine combined heat and power system. $CH_4$ and $CO_2$ simultaneous recovery process has been developed for field plant scale to provide an isothermal, low operating cost method for carrying out the contaminants removal in Land Fill Gas(LFG) by liquid phase catalyst for introduce into the green house for the purpose of $CO_2$ rich cultivation of the plants. Methane purification and carbon dioxide stripping by muti panel autocirculation bubble lift column reactor utilizing Fe-EDTA was conducted for evaluate optimum conditions for land fill gas. Based on inflow rate of LFG as 0.207 $m^3$/min, 5.5 kg/$cm^2$, we designed reactor system for 70% $CH_4$ and 27% $CO_2$ gas introduce into MGT system with $H_2S$ 99% removal efficiency. A green house designed for four different carbon dioxide concentration from ambient air to 1500 ppm by utilizing the exhaust gas and hot water from MGT system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.542-550
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• 2016

This study was carried out to investigate the optimal processing conditions for odor removal and maximal antioxidant effects of oyster (Crassostrea gigas) hydrolysate. The optimal hydrolysis conditions were 3.3% neutrase as the protease, $50^{\circ}C$ as the hydrolysis temperature, and 8.3 h as the hydrolysis time. Fish odor of enzymatic oyster hydrolysate was greatly reduced during Saccharomyces cerevisiae fermentation at $24^{\circ}C$ with 0.5% glucose. The protein content of the fermentation product from oyster hydrolysate powder was 25.7%, which contained the major amino acids Glu, Asp, Lys, Arg, Gly, and Ala, whereas Leu, Ala, Phe, Val, and Tau were abundant free amino acids. The important minor minerals were Zn and Fe. Toxicity against Chang cells was not observed in the fermentation product from the oyster hydrolysate up to $200{\mu}g/mL$. The results suggest that fermentation with S. cerevisiae could reduce the fish odor of enzymatic oyster hydrolysate. The hydrolysate has potential application as a food ingredients and nutraceutical.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.278-283
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• 2003

This study was carried out to examine the nitrogen removal rate of a subsurface-flow treatment wetland system which was constructed on floodplain of the Kwangju River from May to June 2001. Its dimensions were 29m in length, 9m in width and 0.65m in depth. A bottom layer of 45cm in depth was filled with crushed granite with about $15{\sim}30\;mm$ in diameter and a middle layer of 10cm in depth had pea pebbles with about 10 mm in diameter. An upper layer of 5 cm in depth contained course sand. Reeds (Phragmites australis) were transplanted on the surface of the system. They were dug out of natural wetlands and stems were cut at about 40 cm height from their bottom ends. Water of the Kwangju River flowed into it via a pipe by gravity flow and its effluent was funneled back into the river. The height of reed stems was 44.2 cm in July 2001 and 75.3cm in September 2001. The number of stems was increased from $80\;stems/m^2$ in July 2001 to $136\;stems/m^2$ in September 2001. Volume and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Inflow and outflow averaged 40.0 and $39.2\;m^3/day$, respectively. Hydraulic detention time was about 1.5 days. Average nitrogen uptake by reeds was $69.31\;N\;mg/m^2/day$. Removal rate of $NO_3-N$, $NH_3-N$, T-N averaged 195.58, 53.65, and $628.44\;mg/m^2/day$, respectively. Changes of $NO_3-N$ and $NH_3-N$ abatement rates were closely related to those of wetland temperatures. The lower removal rate of nitrogen species compared with that of subsurface-flow wetlands operating in North America could be attributed to the initial stage of the system and inclusion of two cold months into the six-month monitoring period. Increase of standing density of reeds within a few years will develop both root zones suitable for the nitrification of ammonia and surface layer substrates beneficial to the denitrification of nitrates into nitrogen gases, which may lead to increment in the nitrogen retention rate.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.220-225
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• 1998

Background: The patients of facial hyperhidrosis have been known that they had much difficulties in interpersonal relationships and social activities due to excessive hidrosis when they were in stress, hot weather, or having meals. Previous drug therapy and stellate ganglion block have only temporary effects. The surgical method, $T_1$ sympathetomy has the risk of Hornor's syndrome. For that reasons, the sympathicotomy of proximal and distal portions of $T_2$ sympathetic ganglion with electroresectoscope used in transurethral resection seemed to be appropriate procedure, and we would like to report the results of our procedure. Method: Under the general anesthesia with semi-sitting position, and the portal was made through the small incision along the upper border of the 4th rib at the crossing point of mid-axillary line. After the partial collapse of lung by insufflation of 300 to 500 ml of $CO_2$, $T_2$ sympathetic ganglion was identified and resected proximally and distally with electro-cauterization. Finally the lung was expanded by limiting flow until the airway pressure reached 30 to 40 cm$H_2O$, and the wound was closed after removal of electroresectoscope. Result: There was no postoperative complication requiring surgical interventions. The facial sweating was stopped immediately after the operation and all the patients appeared to be satisfied. Conclusion: $T_2$ sympathicotomy with TUR electroresectoscope is thought be the minimal invasive and highly successful method in the treatment of facial hyperhidrosis. But longer terms follow-up will be needed to prove this result.

• Applied Chemistry for Engineering
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• v.33 no.5
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• pp.482-487
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• 2022

In this study, the activity test and characterization were performed to evaluate the hydrogen sulfide removal characteristics using a V/TiO₂ catalyst at room temperature. The optimal vanadium loading was 10 wt%, and the durability was greater than 60 minutes at 60~80% relative humidity. The Brunauer-Emmett-Teller (BET) surface area and raman spectroscopy results confirmed that the structure of the vanadium site exposed to the surface was a dominant factor in catalyst activity. From Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray crystallography (XRD) analyses, it was found that sulfur can be accumulated on the catalyst surface, which results in a decrease in durability under catalytic activity tests. Therefore, it is judged that a combined process of catalytic oxidation and regeneration is needed.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.5
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• pp.559-569
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• 2007

The purposes of this study were to find the main foulant of membrane and the optimal chemical cleaning method for MF(microfiltration) drinking water treatment system using D dam water as water source. The MF pilot plant which can treat maximum $500m^3/d$ consisted of 3 racks and was operated for 10 months under various operation conditions. After 10 months operation, $1^{st}$ and $2^{nd}$ rack of membrane pilot plant system were cleaned chemically and the degree of the restoration of the fouled membrane in terms of the pure water flux was detemnined. Inorganic compounds which contained in chemical cleaning waste was analyzed by Inductively Coupled Plasma (ICP). One membrane module for 3rd rack was disjointed and membrane fouling materials, especially inorganic compounds were investigated by Electron Probe Microanlysis (EPMA) to elucidate the reason of TMP increase. And also, the various chemical reagents (1N HCl or $H_2SO_4$, oxalic acid as acid and 0.3% NaOCl as alkali) were tested by combination of acid and alkali to determine the optimal chemical cleaning method for the MF system using micro-modules manufactured using the disjointed module. It was verified that the inside and outside of membrane module was colorized with black. As a result of the quantitative and semi-qualitative analysis of membrane foulant by ICP, most of inorganic foulant was manganese which is hard to remove by inorganic acid such as HCI. Especially, it was observed by EPMA that Mn was attached more seriously in inside surface of membrane than in outside surface of that. It was supposed that Mn fouling in inside surface of membrane might be caused by the oxidation of soluble manganese (Mn(II)) to insoluble manganese ($MnO_2$) by chlorine containing in backwashing water. The optimal cleaning method for the removal of manganese fouling was consecutive cleaning with the mixture of 1N HCl and 1% of oxalic acid, 0.3% NaOCl, and 1N HCl showing 91% of the restoration of the fouled membrane.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.209-216
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• 2009

The aim of this study was to investigate the removal effects of the color, nutritive salts and other pollutants on piggery slurry by advanced oxidation process (AOP) system. The experimental AOP system was designed to treat 300 L of piggery slurry per hour. To enhance oxidizing power of the experimental APO system, a ultraviolet irradiation system and the ultrasonic system were attached to the AOP system. With 5 min ultrasonic treatment, COD, SS and T-N concentrations were changed from 210, 820, and 309 to 200, 760, and 262 mg/L, respectively. With 10 min ultrasonic treatment, SS and T-N concentrations tended to decrease but T-P concentration was not changed. With the treatment of both ozone and ultrasonic waves for 30 min, COD, SS, T-N and T-P decreased from 238, 900, 400, and 5 to 165, 540, 263, and 4 mg/L, respectively. With the treatment of both ozone and ultraviolet irradiation for 30 min, COD, SS, T-N and T-P decreased from 321, 340, 204, and 15 to 151, 140, 111, and 7 mg/L, respectively, and color was changed from 4,344 to 624.

• 대한예방의학회:학술대회논문집
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• 1994.02b
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• pp.169-179
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• 1994

B-mode ultrasound is being used to assess carotid atherosclerosis in epidemiological studies and clinical trials. Recently the interpretation of measurements made from ultrasound images has been questioned. This study examines the anatomical correlates of B-mode ultrasound of carotid arteries in vitro and in situ in cadavers. Twenty-seven segments of human carotid artery were collected at autopsy. pressure perfusion fixed in buffered 2.5% gluteraldehyde and 4% paraformaldehyde and imaged using an ATL UM-8 (10 MHz single crystal mechanical probe). Each artery was then frozen, sectioned and stained with van Gieson or elastin van Gieson. The thickness of the intima. media and adventitia were measured 'to an accuracy of 0.01 mm from histological sections using a calibrated eye graticule on a light microscope. Shrinkage artifact induced by histological preparation was determined to be 7.8%. Digitised ultra sound images of the artery wall were analysed off-line. The distance from the leading edge of the first interface ($LE_{1}$) to the leading edge of the second interface ($LE_2$) was measured using a dedicated programme. $LE_{1}$-$LE_{2}$ measurements were correlated against histological measurements corrected for shrinkage. Mean values for the far wall were: ultra sound $LE_{1}$-$LE_{2}$ (0.97 mm, S.D. 0.26), total wall thickness (1.05 mm, S.D. 0.37), adventitia (0.35 mm, S.D. 0.16), media (0.61 mm, S.D. 0.18). intima (0.09 mm, S.D. 0.13). Ultrasound measurements corresponded best with total wall thickness, rather than elastin or the intima-media complex. Excision of part of the intima plus media or removal of the adventitia resulted in a corresponding decrease in the $LE_{1}$-$LE_{2}$ distance of the B-mode image. Furthermore. increased wall thickness due to intimal atherosclerotic thickening correlated well with $LE_{1}$-$LE_{2}$ distance of the B-mode images. B-mode images obtained from the carotid arteries in situ in four cadavers also corresponded best with total wall thickness measured from histological sections and not with the thickness of the intima plus media. In conclusion, the $LE_{1}$-$LE_{2}$ distance measured on B-mode images of the carotid artery best represents total wall thickness of intima plus media plus adventitia and not intima plus media alone.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.73.2-73.2
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• 2011

석탄 합성가스 중에는 $H_2S$, HCl, $NH_3$와 같은 불순물이 포함되어 있다. 이러한 가스들은 오염가스 배출과 관련한 환경기준 준수와 터빈과 같은 설비의 보호를 위해 제거되어야 한다. 석탄 합성가스 중 HCl 농도는 탄종에 따라 다르기는 하지만 많게는 1000 ppmv 수준까지 존재한다. 합성가스를 이용하여 발전을 하는 경우 가스터빈 보호를 위해 HCl은 <3 ppmv 이하로 정제되어야 하고, 합성가스를 연료전지에 사용하고자 하는 경우에는 HCl을 <0.5 ppmv 수준까지, 화학원료로 사용하고자 하는 경우에는 <10 ppbv 수준까지 정제하여야 한다. 또한 HCl은 고온 탈황공정에 사용되는 흡수제의 활성에도 장기적으로 부정적인 영향을 주기 때문에 고온에서 HCl을 정제할 수 있는 흡수제가 필요하다. 본 연구에서는 알칼리금속을 활성물질로 사용하여 분무건조법으로 제조한 HCl 흡수제에 대해 물성 및 HCl과의 반응성을 살펴보았다. $300-500^{\circ}C$ 영역에서 K-계 및 Na-계 흡수제에 대해 고정층반응기에서 HCl 가스를 함유한 모사 합성가스를 이용하여 상압 조건에서 Cl 흡수능을 측정한 결과 15wt% 이상의 흡수능을 나타내었으며 반응온도가 높을수록 흡수능이 증가함을 알 수 있었다. XRD 분석을 통하여 Cl은 K 및 Na와 반응하여 KCl과 NaCl을 형성하면서 흡수됨을 알 수 있었다. 20 bar 조건에서 실험한 결과에서도 동일한 경향의 반응성을 나타내었으며 반응온도가 낮을수록 흡수능은 감소하지만 Cl을 더 낮은 농도로 정제할 수 있었다. 본 실험에 사용된 Na 및 K계 흡수제는 모두 연소 후 배가스 중 $CO_2$를 제거하기 위한 흡수제로 사용되는 고체 흡수제이다. 석탄화력발전소 배가스에 연계되어 $CO_2$ 회수실험에 사용되었던 사용 후 $CO_2$ 흡수제에 대해 HCl 흡수 실험을 수행한 결과에서도 우수한 HCl 제거 성능을 보여 주었다. 이로부터, 폐 $CO_2$ 흡수제의 HCl 흡수제로서의 활용가능성을 확인 하였다.