• 한국물환경학회지
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• 제24권3호
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• pp.306-310
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• 2008

Characteristics of microalgal growth was investigated using anaerobic effluent from two-phase animal waste digestor as substrate. Batch experiments were carried out to investigate the effect of the initial nitrogen and phosphorus concentrations on growth of Microcystis aeruginosa, Chlorella sp. and Euglena gracilis. In 400 times diluted anaerobic effluent (TN 3 mg/L), single cell growth of the Euglena gracilis population increased twice without delay, although Chlorella sp. and Microcystis aerugenos take over 144 hours. Similar appearance with single cell growth was observed in mixed cultures. However, microalgae population did not increase under condition of 10 times diluted influent (TP 3 mg/L) in both pure and mixed cultures, which was affected by high organic and nitrogen concentration. Logistic growth model successfully fitted to determine biokinetic parameters such as ${\lambda}$: lag time, ${\mu}m$: maximal specific growth rate, A: asymptote of growth.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.33-36
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• 2004

Two biokinetic models (\circled1 Mrichaelis-Menten kinetics with competitive inhibition \circled2 with both competitive inhibition and Haldane inhibition) for reductive dechlorination were developed and compared with results from batch kinetic tests conducted over a wide range of PCE and TCE concentrations with two different dechlorinating cultures. At PCE concentrations lower than 300 $\mu$M, both model simulated the experimental results well. However, The kinetic model that incorporated both competitive and Haldane inhibitions much better simulated experimental data for PCE concentrations greater than 300-400 $\mu$M, and TCE concentrations at half its solubility limit (4000 $\mu$M). The PM culture showed Haldane inhibition constants of 900, 6000, 7000 $\mu$M for TCE, c-DCE and VC, indicating very weak Haldane inhibition for c-DCE and VC, while the EV culture had lower Haldane inhibition constants for TCE, c-DCE, and VC of 900, 750, and 750 $\mu$M, respectively. The BM culture had better transformation abilities than the individual cultures over a wide range of PCE and TCE concentrations. Modeling results indicated that a combination of competitive and Haldane inhibition kinetics is required to simulate dechlorination over a broad range of concentrations up to the solubility limits of PCE and TCE.

• 한국대기환경학회지
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• 제8권4호
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• pp.269-276
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• 1992

인체에 영향을 미치는 중금속은 대개 환경중에서 음식물, 공기, 먼지 및 음료수를 통하여 축적된다. 본 연구는 중금속중 납이 인체에 미치는 유해정도를 평가하기 위하여 서울과 여주등 대기중 납농도가 차이가 나는 지역주민들의 혈액중 납농도를 측정하여 Bio kinetic Model을 이용 납에 대한 인체의 위해성 정도를 알아보았으며 그 결과는 다음과 같다. - 지역별로는 혈액중 납농도가 별다른 차이를 보이지 않았으나 나이와 성별에 따라서는 다소 차이가 나고 있다. - 또한 혈액중 납농도는 log normal 분포를 나타내고 있음. - 기하표준편차는 1.2 $\sim$ 1.3 정도의 값으로 미국 EPA에서 추정한 1.31 $\sim$ 1.41의 값보다 약간 적은 값을 나타냈다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.1-7
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• 2015

The most critical health effect of lead exposure is the neurodevelopmental effect to children caused by the increased blood lead level. Therefore, the endpoint of the risk assessment for lead-contaminated sites should be set at the blood lead level of children. In foreign countries, the risk assessment for lead-contaminated sites is conducted by estimating the increased blood lead level of children via oral intake and/or inhalation (United States Environmental Protection Agency, USEPA), or by comparing the estimated oral dose to the threshold oral dose of lead, which is derived from the permissible blood lead level of children (Dutch National Institute for Public Health and the Environment, RIVM). For the risk assessment, USEPA employs Integrated-Exposure-Uptake-Biokinetic (IEUBK) Model to check whether the estimated portion of children whose blood lead level exceeds 10 µg/dL, threshold blood lead level determined by USEPA, is higher than 5%, while Dutch RIVM compares the estimated oral dose of lead to the threshold oral dose (2.8 µg/kg-day), which is derived from the permissible blood lead level of children. In Korea, like The Netherlands, risk assessment for lead-contaminated sites is conducted by comparing the estimated oral dose to the threshold oral dose; however, because the threshold oral dose listed in Korean risk assessment guidance is an unidentified value, it is recommended to revise the existing threshold oral dose described in Korean risk assessment guidance. And, if significant lead exposure via inhalation is suspected, it is useful to employ IEUBK Model to derive the risk posed via multimedia exposure (i.e., both oral ingestion and inhalation).

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.381-384
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• 2002

Response surface methodology (RSM) was successfully applied to optimize for the production of Ganoderma lucidum in batch fermentations using the whey (40,000 mg latose/L) as substrate. This study was performed according to the central composite design (CCD) with respect to pH and temperature, where the designed intervals were 3.3$22.9^{\circ}C$$37.1^{\circ}C$, respectively. A second-order factorial design of the experiments was used to build empirical models providing a quantitative interpretation of the relationships between the two variables. The optimum conditions to maximize the production of G. lucidum were pH 4.2 and $28.3^{\circ}C$. At optimum conditions, the mycelial dry weight (MDW) and residual soluble COD (SCOD) were simultaneously used to evaluate the biokinetic coefficients assocoated with substrate inhibition model by nonlinear least squares method with 95% confidence interval. The. maximum microbial growth rates (${\mu}m$), half saturation coefficient ($K_s$), and the inhibition substrate concentration ($K_{is}$) were determined to be 0.095 l/hr, 128,000 mg SCOD/L and 49,000 mg SCOD/L, respectively. And the microbial yield coefficient (Y), biomass decay rate coefficient ($K_d$), and the maintenance energy coefficient ($m_s$) were determined to be 0.37 mg MDW/mg SCOD, 0.001 1/hr, and 0.0015 1/hr, respectively.

• Journal of Radiation Protection and Research
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• 제31권3호
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• pp.135-140
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• 2006

비밀봉 방사성물질의 취급 사고시 방사성핵종은 흡입과 취식의 두 가지 경로로 섭취될 수 있다. 이때 일상 감시처럼 하나의 섭취경로만 가정하여 예탁유효선량을 평가하면 심각한 오차를 유발할 수 없다. 이러한 잠재 오차를 제시하기 위해 총 섭취에 대한 흡입섭취의 비율을 달리할 때 예탁유효선량의 변동을 분석하였다. $^{241}Am$(AMAD 5 ${\mu}m$, 흡수형 M)을 대상으로 핵종의 생물역동학적 모델과 데이터를 이용하여 여러 흡입섭취 분율에서 폐, 소변 및 대변에 대한 바이오어세이 측정치를 모의하였다. 섭취 3일 후 예상 측정치를 이용하고 단일 경로 섭취를 가정한 경우 평가된 예탁유효선량의 잠재 오차는 -100%에서부터 많게는 +34,000%에 이르는 것으로 나타났다. 흡입섭취가 있을 때 대변만 분석하면 큰 오차가 발생하였다. 섭취경로 오판에 따르는 선량평가의 오차를 줄이기 위해 두 종류의 바이오어세이를 이용하는 전략을 제안하였다.