• Korean Journal of Construction Engineering and Management
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• v.9 no.4
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• pp.84-91
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• 2008

"Eco-friendly construction" is an emerging issue in the building industry. Main purpose of the eco-friendly construction is to sustain the health and environment of building residents and to minimize the harmful effect on their environment. Apartment residents have great concern on eco-product, since many cases are reported that Sick Building Syndrome is caused by toxic substance from building materials. Environmental performance is to meet through using the highest grade eco-friendly materials. However, generally eco-friendly materials are more expensive than normal materials, Therefore, using eco-friendly materials at public housing project is limited to economical aspect. The purpose of this paper is development of eco-friendly material selection model considered cost efficiency. The selection of Eco-friendly finishing materials and their methods are constructed to consider environmental performance level and cost index compositively. Development of eco-friendly material selection method is economic and reasonable one when public housing is constructed.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.953-956
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• 2007

"Eco-friendly construction"is an emerging issue in the building industry. Main purpose of the eco-friendly construction is to sustain the health and environment of building residents and to minimize the harmful effect on their environment. Apartment residents have great concern on eco-product, since many cases are reported that Sick Building Syndrome is caused by toxic substance from building materials. Environmental performance is to meet through using the highest grade eco-friendly materials. However, generally eco-friendly materials are more expensive than normal materials. Therefore using eco-friendly materials at public housing project is limited to economical aspect. The purpose of this paper is development of eco-friendly material selection model considered cost efficiency. The selection of Eco-friendly finishing materials and their methods are constructed to consider environmental performance level and cost index compositively. Development of eco-friendly material selection method is economic and reasonable one when public housing is constructed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1415-1423
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• 2007

Carbon tetrachloride ($CCl_4$)-induced liver injury depends on a toxic agent that has to be metabolized by the liver NAPDH-cytochrome P450 enzyme system to a highly reactive intermediate. Alternations in the activity of cytochrome P450 enzymes affect the susceptibility to hepatic injury from $CCl_4$. In this study, we evaluated the potential protective activity of the traditional Korean medicinal herb, Corni fructus (CF), against an experimental model of hepatotoxicity induced by $CCl_4$. The CF exhibited a hepatoprotective activity against $CCl_4-induced$ liver damage in Sprague-Dawley (SD) rats, as measured by GOT, GPT, ALP and histological observation. The CF also showed significant decrease of malodialdehyde (MDA) and increase of glutathion (GSH), catalase activity in rat liver homogenate. In addition, the expression of CYP2E1, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis, was significantly decreased in the liver of CF treated SD rats. But $CCl_4$ and CF has no significant effect on 1A1 and 3A1 isoform of cytochrome P450. Based on these findings, it is suggested that hepatoprotective effects of CF possibly related to antioxidative effects and regulation of CYP2E1 expression.

• Environmental Engineering Research
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• v.17 no.4
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• pp.185-190
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• 2012

Rejection characteristics of perchlorate ($ClO_4^-$) were examined for commercially available reverse osmosis (RO) and nanofiltration (NF) membranes. A bench-scale dead-end stirred-cell filtration system was employed to determine the toxic ion rejection and the membrane flux. Model water solutions were used to prepare $ClO_4^-$ solutions (approximately, $1,000{\mu}g/L$) in the presence of background salts (NaCl, $Na_2SO_4$, and $CaCl_2$) at various pH values (3.5, 7, and 9.5) and solution ionic strengths (0.001, 0.01, and 0.01 M NaCl) in the presence of natural organic matter (NOM). Rejection by the membranes increased with increasing solution pH owing to increasingly negative membrane charge. In addition, the rejection of the target ion by the membranes increased with increasing solution ionic strength. The rejection of $ClO_4^-$ was consistently higher for the RO membrane than for the NF membrane and $ClO_4^-$ rejection followed the order $CaCl_2$ < NaCl < $Na_2SO_4$ at conditions of constant pH and ionic strength for both the RO and NF membranes. The possible influence of NOM on $ClO_4^-$ rejection by the membranes was also explored.

• Environmental Analysis Health and Toxicology
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• v.26
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• pp.10.1-10.7
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• 2011

Objects: Chironomus riparius, a non-biting midge (Chironomidae, Diptera), is extensively used as a model organism in aquatic ecotoxicological studies, and considering the potential of C. riparius larvae as a bio-monitoring species, little is known about its genome sequences. This study reports the results of an Expressed Sequence Tags (ESTs) sequencing project conducted on C. riparius larvae using 454 pyrosequencing. Method: To gain a better understanding of C. riparius transcriptome, we generated ESTs database of C.ripairus using pyrosequencing method. Results: Sequencing runs, using normalized cDNA collections from fourth instar larvae, yielded 20,020 expressed sequence tags, which were assembled into 8,565 contigs and 11,455 singletons. Sequence analysis was performed by BlastX search against the National Center for Biotechnology Information (NCBI) nucleotide (nr) and uniprot protein database. Based on the gene ontology classifications, 24% (E-value${\leq}1^{-5}$) of the sequences had known gene functions, 24% had unknown functions and 52% of sequences did not match any known sequences in the existing database. Sequence comparison revealed 81% of the genes have homologous genes among other insects belonging to the order Diptera providing tools for comparative genome analyses. Targeted searches using these annotations identified genes associated with essential metabolic pathways, signaling pathways, detoxification of toxic metabolites and stress response genes of ecotoxicological interest. Conclusions: The results obtained from this study would eventually make ecotoxicogenomics possible in a truly environmentally relevant species, such as, C. riparius.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3319-3326
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• 2014

Eosin yellow is used a dye and colorant but it is harmful toxic substance. In this paper, batch adsorption studies were carried out for equilibrium, kinetics and thermodynamic parameters for eosin yellow adsorption by activated carbon with varying the operating variables like pH, initial concentration, contact time. Equilibrium adsorption data were fitted into Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms. By estimated Langmuir constant value, $R_L$=0.067-0.083, and Freundlich constant value, $\frac{1}{n}=0.237-0.267$, this process could be employed as effective treatment for removal of eosin yellow. From calculated Temkin constant, value, B=1.868-2.855 J/mol, and Dubinin-Radushkevich constant, value, E=5.345-5.735 kJ/mol, this adsorption process is physical adsorption. From kinetic experiments, the adsorption process were found to confirm to the pseudo second order model with good correlation coefficient($r^2$=0.995-0.998). The mechanism of the adsorption process was determined two step like as boundary and intraparticle diffusion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.29-34
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• 2015

The objective of this study was to obtain data on the safety-in-use of nano calcium as a dietary supplement by assessing its acute and subacute oral toxicities in female and male Sprague-Dawley rats. A single oral dose of 5,000 mg/kg of nano calcium did not result in mortality or significant changes in the general behavior and gross appearance of the internal organs of rats. For subacute toxicity study, nano calcium was administered orally at a dose of 1,000 mg/kg daily for 14 days. There were no significant differences in organ weights between control and treated groups of both sexes. Hematological analysis and blood chemistry revealed no toxic effects of nano calcium. Pathologically, neither gross abnormalities nor histopathological changes were observed. These results show that nano calcium possesses very low toxicity as indicated in a rat model.

• Journal of Ocean Engineering and Technology
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• v.27 no.5
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• pp.105-114
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• 2013

Lots of orders of special vessels and offshore plants for developing the resources in deepwater have been increased in recent. Because the most of accidents on those structures are caused by fire and explosion, many researchers have been investigated quantitatively to predict the cause and effect of fire and explosion based on both experiments and numerical simulations. The first step of the evaluation procedures leading to fire and explosion is to predict the dispersion of flammable or toxic material, in which the released material mixes with surrounding air and be diluted. In particular turbulent mixing, but density differences due to molecular weight or temperature as well as diffusion will contribute to the mixing. In the present paper, the numerical simulation of hydrogen dispersion inside a simple-shaped offshore structure was performed using a commercial CFD program, ANSYS-CFX. The simulated results for concentration of released hydrogen are compared to those of experiment and other simulation in Jordan et al.(2007). As a result, it is seen that the present simulation results are closer to the experiments than other simulation ones. Also it seems that the hydrogen dispersion is closely related to turbulent mixing and the selection of the turbulence model properly is significantly of importance to the reproduction of dispersion phenomena.

• Advances in environmental research
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• v.9 no.2
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• pp.135-150
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• 2020

Many industries, such as textiles, chemical refineries, leather, plastics and paper, use different dyes in various process steps. At the same time, these industrial sectors are responsible for discharging contaminants that are harmful and toxic to humans and microorganisms by introducing synthetic dyes into wastewater. Of these dyes, methylene blue dye, which is classified as basic dyes, is accepted as a model dye. For this reason, methylene blue dye was selected in the study and its removal from the water was studied. In this study, two efficient biosorbents were developed from chitosan and sunflower waste, an agro-industrial waste and modified using iron nanoparticles. The biosorption efficiency was evaluated for methylene blue (MB) dye removal from aqueous solution under various parameters such as treating agent, solution pH, biosorbent dosage, contact time, initial dye concentration and temperature. We investigated the kinetic properties of dye removal from water for Chitosan-Sunflower (CS), Chitosan-Sunflower-Nanoiron (CSN). When the wavelength of MB dye was spectrophotometrically scanned, the maximum absorbance was determined as 660 nm. For the core shell biosorbents we obtained, we found that the optimum time for removal of MB from wastewater was 60 min. The pH of the best pH was determined as 5 in the studied pH. The most suitable temperature for the experiment was determined as 30℃. SEM-EDAX, TEM, XRD, and FTIR techniques were used to characterize biosorbents produced and modified in the experimental stage and to monitor the change of biosorbent after dye removal. The interactions of the paint with the surface used for removal were explained by these techniques. It was calculated that 80% of CS and 88% of CSN removed MB in optimum conditions. Also, the absorption of MB dye onto the surface was investigated by Langmiur and Frendlinch isotherms and it was determined from the results that the removal was more compatible with Langmiur isotherm.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.106-106
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• 2019

많은 도심의 하천들은 오염물질의 유입에 취약하다. 최근 신소재 공학 등 첨단산업이 발전하게 되면서 유해화학물질의 유입문제는 더욱 대두되고 있으며, 실제로 최근 유해화학물질 유입사고 발생건수가 늘어나고 있다. 특히 국내 취수량의 90%는 지표수에서 취수하고 있어, 하천오염사고는 직접적인 피해로 이어지게 된다. 따라서 이러한 사고에 대응하기 위하여 수환경에 유입된 유해물질의 거동 매커니즘을 반영한 수질해석이 필요하다. 수체 내에 유입된 유해화학물질은 기본적으로 흐름에 따른 이송 확산을 하며 흡 탈착, 휘발, 침전 부유, 생화학 반응과 같은 다양한 반응과 함께 혼합거동을 한다. 특히 소수성물질의 경우 용해된 상태뿐만 아니라, 유사에 흡착된 상태로 수체에 존재하게 된다. 결국 유해화학물질의 거동을 해석하기 위해서는 유체의 흐름 해석뿐만 아니라 수체에 존재하는 유사의 이송 또한 해석해야한다. 본 연구에서는 흐름해석을 위하여 서울대에서 개발한 흐름모형(HDM-2D)을 사용하였으며, 부유사 거동모의를 위해 부유사거동모형(STM-2D)을 개발하였다. 또한 유해화학물질의 거동모의를 위해 서울대에서 개발한 수질모형(CTM-2D)에 생성/소멸항을 추가하였으며 흐름모형과 부유사모형과의 연계를 통해 유해화학물질의 혼합거동 수치모형을 개발하였다. 각 반응항(흡 탈착, 휘발, 침전 부유, 생화학 반응)을 수치모형에 반영 시에는 보통 두 계(물-토양, 물-공기) 사이의 선형 물질교환으로 이해된다. 따라서 물질의 각 반응 별 평형농도와 물질교환속도계수를 추정식을 통해 산정하여 사용하게 된다. 하지만 각 기작이 반영유무에 따라 계산시간 및 필요입력변수가 늘어나게 되므로, 유해화학물질 유입사고와 같은 빠른 대처가 필요한 경우 각 반응 텀의 유의성을 판단하여 모형에 반영여부를 결정을 통해 경제적인 모의를 할 수 있어야 한다. 이에 따라 본 연구에서는 개발된 모형의 각 매개변수들의 민감도를 분석하고, 흐름조건 및 물질의 특성에 따른 반응항의 유의성을 판단하였다. 본 연구에서는 개발된 모형(부유사거동모형, 유해화학물질의 혼합거동모형)은 해석해 및 현장 데이터와 비교검증을 통해 개발을 완료하였으며, 각 반응항의 민감도 분석을 통해 매개변수의 임계값을 결정하였다.