• Title/Summary/Keyword: 유효농도

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Indoor Radon Levels and Effective Dose Estimation in Learning and Common Living Space of University (대학 내 학습공간과 공동 생활공간에 대한 실내 라돈 농도 측정과 유효선량 산출)

  • Kim, Jung-Su
    • Journal of the Korean Society of Radiology
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    • v.12 no.3
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    • pp.329-334
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    • 2018
  • Radon which is natural component of air is a colorless and odorless radioactive gas. Radon exposure can also occur from some building materials if they are made from radon-containing substances by breathing. In this study, The radiation dose of radon concentration was detected at 8 buildings of the A university during 3-month from June. 2017 to August. 2017. We detected indoor radon exposure at 8 building of the university and estimated annual effective dose. The radon concentration of Hall G and Hall F of the A university represented 81 and $14Bq/m^3$ respectively and average indoor radon concentration represented $41.63Bq/m^3$. Average effective dose was estimated 0.40 mSv/y, maximum effective dose was 0.78 mSv/y and minimum effective dose was 0.13 mSv/y respectively. University is the place that students spend the almost whole time. We suggest ventilation and appropriate management of a building, which could reduce the natural radiation exposure by radon concentration.

A Study on the NOx Reduction of Flue Gas Using Un-divided Electrolysis of Seawater (무격막식 해수 전기분해 방식을 통한 배연 탈질에 관한 연구)

  • Kim, Tae-Woo;Choi, Su-Jin;Kim, Jong-Hwa;Song, Ju-Yeong
    • Korean Chemical Engineering Research
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    • v.50 no.5
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    • pp.825-829
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    • 2012
  • In this study, we investigated NO oxidation characteristic that depends on available chlorine concentration and temperature of seawater which is treated by un-divided electrolysis. Reactant gas passed through bubbling reactors which is filled with electrolyzed water and then NO concentration change was analyzed. In the closed-loop electrolysis system, concentration of available chlorine increased with electrolysis time. The higher oxidation rate of NO to $NO_2$ was obtained with the higher concentration of available chlorine. Oxidation of NO was fast when temperature of electrolyzed water was high, in the case of same concentration of available chlorine.

The investigation of antibiotic resistance community in environment samples using EC (effective concentration) concept (EC개념을 사용하여 환경 표본안에 항생제 저항 군집에 관한 연구)

  • Kim, Sung-Pyo;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.13 no.2
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    • pp.181-187
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    • 2011
  • The overall objective of this study is to develop the engineering-friendly-methodology which can investigate the fate of antibiotic resistance in environment microbial community. For this purpose, effective concentration (EC) concept was adopted with cultural based method which is currently used in engineering practice. When a tetracyline antibiotic was present as selective pressure agent among microbial community, activated sludge, the $EC_{50}$ and/or $EC_{90}$ of tetracycline in microbial community were statistically increased compared to control, especially higher growth rate and organic loading conditions of SBRs. Therefore, these results strongly suggested that the continuous monitoring of EC in microbial community can be used for characterizing the fate of tetracycline resistance community in environmental samples.

급성 정신분열병 환자에 대한 Risperidone(R 64766)의 임상 효과 및 안정성 연구

  • 우종인;권준수;김성윤
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.04a
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    • pp.165-165
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    • 1993
  • 목적:지금까지 Risperidone의 치료 효능과 안전성에 대한 연구들이 모두 만성 정신분열병 환자들만을 대상으로 이루어졌고, 효율적인 약물 요법의 중요한 지침이 되는 유효치료용량(effective therapeutic dosage)에 대한 연구가 이루어지지 않고 있는 바, 본 연구에서는 초발인 급성 정신분열병 환자들을 대상으로 첫째, Risperidone의 항정신병 효과(antipsychotic effect)와 추체외로계증상(extrapyramidal symptoms)을 평가하고 둘째, Risperidone의 항정신병 효과와 혈장 Risperidone 및 9-hydroxyrisperidone 농도와의 상관관계를 분석하여 유효혈장농도(therapeutic dose range)와 유효치료용량(effective therapeutic dosage)의 존재 여부를 검토코자 한다. 방법: DSM-III-R 진단기준(APA 1987)예 의해 정신분열병형 장애로 진단된 환자 11명(남자 5, 여자 6)을 대상으로 Risperidone을 이중맹검법(double blind design)으로 6주간 투약하였다. 정신병리의 평가는 PANSS(Kay 1988)를 이용하였고 추체외로계 부작용의 평가는 ESRS(Chouinard 1980)를 이용하였다. 혈장 Risperidone 농도와 혈장 9-hydroxyrisperidone 농도는 Jansen사의 Radioimmunoassay Kit를 이용하여 3회 측정하였다. 결과: PANSS 점수는 Risperidone 투여 후 1주째부터 통계적으로 유의하게 감소하였다. Parkinsonism과 dyskinesa에 대한 physician's examination 점수는 전체 연구 기간 동안 유의한 변화를 보이지 않았다. Dystonia에 대한 physician's examination 점수는 Risperidone 투여 후 1주째에는 평균 5.96점으로 높았으나 2주째부터 통계적으로 유의하게 감소되어 6주째에는 유지되었다. 혈장 Risperidone 농도와 혈장 9-hydroxyrisperidone 농도는 PANSS 점수와 유의한 상관관계를 보이지 않았다.

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Investigation of the Ethanol Fermentation Characteristics of K. fragilis by Semicontinuous Culture (반 연속식 배양에 의한 효모 K. fragilis의 알콜발효 특성에 관한 연구)

  • 허병기;류장수목영일
    • KSBB Journal
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    • v.4 no.2
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    • pp.185-190
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    • 1989
  • Semicontinuous alcohol fermentation of Jerusalem Artichoke by K. fragilis CBS 1555 was performed to investigate the effect of the effective dilution rate and influent sugar concentration to the ethanol concentration and alcohol productivity at steady state. When the time interval for the replacement of fresh influent with fermentation broth was less than or equal to 1 hr, the effective dilution rate was found out to be equal to the specific growth rate. Wash out was not occurred until the effective dilution rate, 0.425 hr-1, and the maximum alcohol productivity was around 5.5 g/1·hr. In this case, the effective dilution rate was 0.25 hr-1 and the influent sugar concentration was distributed from 85 g/l to 135 g/1.

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Soil nitrogen availability in a thinned Larix leptolepis plantation using ion exchange resin bags (이온교환수지봉지를 이용한 일본잎갈나무 간벌지의 질소 유효도 측정)

  • Son, Yo-Whan;Kim, Hyun-Seop
    • Korean Journal of Environmental Agriculture
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    • v.19 no.2
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    • pp.188-190
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    • 2000
  • We explored changes in soil nitrogen (N) availability in a thinned (control, light, moderate, and heavy thinning) Larix leptolepis plantation determined by using ion exchange resin bags. Nitrogen availability varied among measurement periods, however, total available N (ammonium plus nitrate) concentrations did not change significantly in the 1 year since thinning. We found higher N availability in summer and fall than in winter.

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Adsorption Characteristics of Alkaline Copper Quat Preservative Components in Wood (구리⋅알킬암모늄화합물계 목재방부제 (ACQ) 유효성분의 목재 흡착 특성)

  • Lee, Jong-Shin;Choi, Gwang-Sik
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.4
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    • pp.491-498
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    • 2014
  • In order to obtain basic data for concentration control of alkaline copper quat (ACQ) solution in wood preservative treatment, this study investigates the change of concentration and adsorption of treating solution and active ingredient, copper oxide (CuO) and didecyldimethyl ammonium chloride (DDAC), in the process of recycling of ACQ solution. Japanese larch (Larix leptolepis), Douglas-fir (Psedotsuga menziesii) and Radiata pine (Pinus radiata) were treated with ACQ solution. The active ingredient concentration of ACQ solution was decreased continuously with increase of recycling. There are differences between extent of concentration decrease of Cu (as CuO) and DDAC. DDAC was decreased more quickly and to a higher degree than Cu for all recycling. The extent of DDAC concentration decrease was remarkable than that of Cu for wood species. The amount of DDAC adsorbed into wood decreased with the increase of ACQ solution recycling, but adsorption of Cu was little difference regardless of recycling. The adsorption of Cu into wood increased as DDAC concentration decrease by recycling of ACQ solution. This is likely due to decrease of DDAC competition with Cu for the same reaction site in wood.