• Nuclear Engineering and Technology
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• 제40권1호
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• pp.93-98
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• 2008

Several adhesive tapes have been studied in terms of their suitability for securing gold wires into positions for neutron flux measurements in the reactor core and irradiation facilities surrounding the core of the Open Pool Australian Light water (OPAL) reactor. Gamma ray spectrometry has been performed on each irradiated tape in order to identify and quantify activated components. Numerous metallic impurities have been identified in all tapes. Calculations relating to both the effective neutron shielding properties of the tapes and the error in measurement of the $^{198}Au$ activity caused by superfluous activity due to residual tape have been made. The most important identified effects were the prolonged cooling times required before safe enough levels of radioactivity to allow handling were reached, and extra activity caused by residual tape when measured with an ionisation chamber. Knowledge of the most suitable tape can allow a minimal contribution due to these effects, and the use of gamma spectrometry in preference to ionisation chamber measurements of the flux wires is shown to make all systematic errors due to the tape completely negligible.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.25-32
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• 2014

The amount of TPH contaminated soil treated at off-site remediation facilities is ever increasing. For the recycle of the treated-soil on farmlands, it is necessary to restore biological and physico-chemical soil characteristics and to remove residual TPH in the soil by an economic polishing treatment method such as phytoremediation. In this study, a series of experiments was performed to select suitable plant species and to devise a proper planting method for the phyto-restoration of TPH-treated soil. Rye (Secale cereale) was selected as test species through a germination test, among 5 other plants. Five 7-day-old rye seedlings were planted in a plastic pot, 20 cm in height and 15 cm in diameter. The pot was filled with TPH-treated soil (residual TPH of 1,118 mg/kg) up to 15 cm, and upper 5 cm was filled with horticulture soil to prevent TPH toxic effects and to act as root growth zone. The planted pot was cultivated in a greenhouse for 38 days along with the control that rye planted in a normal soil and the blank with no plants. After 38 days, the above-ground biomass of rye in the TPH-treated soil was 30.6% less than that in the control, however, the photosynthetic activity of the leaf remained equal on both treatments. Soil DHA (dehydrogenase activity) increased 186 times in the rye treatment compared to 10.8 times in the blank. The gross TPH removal (%) in the planted soil and the blank soil was 34.5% and 18.4%, respectively, resulting in 16.1% increase of net TPH removal. Promotion of microbial activity by root exudate, increase in soil permeability and air ventilation as well as direct uptake and degradation by planted rye may have contributed to the higher TPH removal rate. Therefore, planting rye on the TPH-treated soil with the root growth zone method showed both the potential of restoring biological soil properties and the possibility of residual TPH removal that may allow the recycle of the treated soil to farmlands.

• Journal of Microbiology and Biotechnology
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• 제19권5호
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• pp.468-473
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• 2009

The antibiotic meroparamycin was produced in the free culture system of Streptomyces sp. strain MAR01. Five solid substrates (rice, wheat bran, Quaker, bread, and ground corn) were screened for their ability to support meroparamycin production in solid-state fermentation. In batch culture, wheat bran recorded the highest antibacterial activity with the lowest residual substrate values. The highest residual substrate values were recorded for both ground corn and Quaker. On the other hand, no antibacterial activity was detected for rice as a solid substrate. The use of the original strength of starch-nitrate medium in the solid-state fermentation gave a lower antibacterial activity compared with the free culture system. Doubling the strength of this medium resulted in the increase in the activity to be equivalent to the free culture. The initial pH (7.0) of the culture medium and 2 ml of spore suspension (1 ml contains $5{\times}10^{9}spores/ml$) were the optima for antibiotic production. The water was the best eluent for the extraction of the antibiotic from the solid-state culture. Ten min was enough time to extract the antibiotic using a mixer, whereas, 60 min was required when shaking was applied. Semicontinuous production of meroparamycin using a percolation method demonstrated a more or less constant antibacterial activity over 4 runs ($450-480{\mu}g/ml$). The semicontinuous production of the antibiotic was monitored in a fixed-bed bioreactor and the maximum activity was attained after the fourth run ($510{\mu}g/ml$) and the overall process continued for 85 days.

• Applied Biological Chemistry
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• 제38권2호
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• pp.106-110
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• 1995

알칼리성 protease를 생산하는 균을 고추장에서 분리하여 Alteromonas sp. CN301로 동정하고 그 알칼리성 protease를 생산하여 정제효소의 성질을 조사한 결과, 최적 pH 12.0, 최적 온도 $35^{\circ}C$이었으며 pH 안정성은 $pH\;6.0{\sim}13.0$ 범위에서 80% 이상의 잔존효소 활성을 나타냈고 $50^{\circ}C$에서 1시간 처리로 64%의 활성을 보였다. SDS-PAGE에 의한 분자량은 31,000 dalton이었고 $Hg^{2+}$를 제외한 다른 금속이온에 대해서는 저해를 받지 않았다. 계면활성제인 Triton X-100, Tween 20과 80은 이 효소의 활성을 상승시키는 효과를 보였으며 EDTA와 PMSF에 의하여 효소활성이 저해되므로 효소분자 중에 금속이온을 가지는 serine protease로 생각되었다.

• 대한한방내과학회지
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• 제1권1호
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• pp.92-97
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• 1976

Upon feeding dried Ginseng to rats of either low-protein or high protein diet ethanol was administered intraperitoneally and disappearance rate blood alcohol was enzymatically measure. In terms of residual blood alcohol after a time lapse of 3.5 hours between intraperitonial administration and blood withdrawal neither ginseng nor ginseng plus 40% casein did improve the rate, of alcohol clearance but sexual difference was clearly demonstrated in favor of female rats. In the case of blood withdrawn only 2 hours after intraperitoneal injection of alcohol, the tendency of female superiority in alcohol clearance rate is demonstrated when a comparison is made among the groups fed with ginseng and this was particularly true is groups of rats fed with basal diet plus 1 percent ginseng residual blood ethanol being 15.4 mg/ml vs. 8.8 mg/ml. Liver homogenate alcohol dehydrogenase activity measured in terms of residual ethanol content after in vitro reaction on which a known amount of alcohol was added clearly demonstrated a male superiority in alcohol clearance.

• 약학회지
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• 제40권1호
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• pp.65-71
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• 1996

Characterization of Polyphenol oxidase (PPO) in Perillae Folium, particullarly inhibitor studies were investigated. This enzyme was stable at pH 5.0 and the residual activity of PPO at ${\geq}$ ph 5.5 was estimated to be very low. PPO activity was decreased slightly by adding amino acid with catechol as a substrate, particullary PPO activity was inhibited markedly by cystein, histidine, lysine and arginine. In the absorption spectra of the product formed when catechol was oxidized by PPO, with a ${\lambda}_{max}$ at 410nm, the peak shifted toward ${\lambda}_{max}$ 520nm by addition of L-proline. At relatively low concentrations($10^{-3}M$), sulfite and dithiothreithol completely inhibited PPO activity. Inhibition of PPO activity by amino acids and inhibitors increased or decreased depending on the pH used to measure it.

• 한국미생물·생명공학회지
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• 제20권2호
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• pp.150-155
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• 1992

토양 분리 균주로부터 얻은 배양액을 20-80 황산암모늄으로 분획한 후 세포의 cytosine deaminase의 성질을 검토하였다. 이 효소는 cytosine과 5-fluorocytosine(5-FC)에 기질 특이성을 가짐으로서 각각 uracil과 5-fluorouracil(5-FU)로 전환을 촉매하였다. 효소안정성에 대한 온도와 보존기간은 tris-HC1 완충용액에서 검토한 결과 최적온도는 $50^{\circ}C$ 부근이하에서 90 이상의 잔존활성을, 보존시간은 4일정도에서 80 이상의 잔존활성을 유지하였다. 최대 pH 8.0과 $37^{\circ}C$의 온도에서 나타났다. 활성에 적당한 pH는 8.0~8.5였고, 온도는 37~$45^{\circ}C$의 범위였다.

• 한국응용곤충학회지
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• 제40권4호
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• pp.327-335
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• 2001

원예작물 중 온실가루이의 발생이 가장 심한 오이를 대상작물로 선정하여 온실가루이에 대한 기존의 살충제를 이용한 화학적 방제체계를 수립하기 위하여, 중후기에 방제효과와 잔효독성, 엽중 농약 잔류량 조사, 방제횟수 절감, 농약 저항성 발달 및 오이의 수량 등 온실가루이 방제체계 확립에 필요한 기초적인 사항을 조사하였다. 조사결과 온실가루이에 대하여 가장 효과적인 살충제는 furathiocarb였고 특히 이 약제는 carbofuran으로 더욱 강력한 활성화 과정을 거치면서 온실가루이의 저항성 발달이 비교적 더디게 나타났고 따라서 방제효과가 길고 결과적으로 방제횟수도 줄이는데 기여하는 것으로 판명되었다. 이와는 달리 기존의 다른 약제들에 대해서는 합성피레스로이드계의 약제, deltamethrin, etopenprox, zetacypermethrin 등에 대해서는 저항성 발달이 빨리 나타났고, 일부 유기인계 약제, methidathion, phenthoate, profenofos 등의 경우에는 살포 후 분해가 빨리되어 약효의 상실이 빨라짐으로 인해서 결과적으로 살포회수를 늘여야하는 것으로 나타났다. 이들 기존 살충제들에 대한 저항성 온실가루이의 발생으로 방제가 곤란한 경우에 acetamiprid가 대체 약제로서 유망하였다.

• 대한화장품학회지
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• 제5권1호
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• pp.43-57
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• 1975

• 농약과학회지
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• 제17권3호
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• pp.206-212
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• 2013

본 연구는 살충제의 잔효성을 이용하여 집합페로몬 통발트랩에 유인된 톱다리개미허리노린재의 살충효과를 평가하였다. 트랩 내에 방사한 1령, 2령 약충의 트랩 이탈시간을 조사한 결과 접종 후 70분 이내에 100% 탈출률을 보였다. 노린재류에 등록된 6종의 약제를 3종류의 재질[나무(각목), 철(철망), 플라스틱(PVC)]에 처리하여 살충활성을 조사한 결과, bifenthrin, fenitrothion 2종의 약제가 1령, 3령, 5령 및 약충 그리고 성충에서 100% 살충활성을 나타냈다. 2종 약제의 재질에 따른 약제 잔효성은 플라스틱 표면에 처리하였을 때, 5령을 제외한 1, 3령 약충 및 성충에서 15일 이상 100% 살충효과를 나타냈다. 플라스틱 재질의 트랩에 대한 야외실험에서는 2종 약제 모두 1령 약충과 성충에 처리 후 10일 후까지 100%의 살충률을 보였으며, 그 후 살충률이 점차 감소하였다. 본 연구결과를 통하여 집합 페로몬 트랩과 살충제를 이용한 톱다리개미허리노린재의 방제효율을 개선에 도움이 될 것으로 생각된다.