• Environmental Engineering Research
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• 제13권1호
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• pp.19-27
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• 2008

Simultaneous removal of ternary gases of $NH_3$, $H_2S$ and toluene in a contaminated air stream was investigated over 180 days in a biofilter. A commercially available inorganic/polymeric composite chip with a large void volume (bed porosity > 0.80) was used as a microbial support. Multiple microorganisms including Nitrosomonas and Nitrobactor for nitrogen removal, Thiobacillus thioparus (ATCC 23645) for $H_2S$ removal and Pseudomonas aeruginosa (ATCC 15692), Pseudomonas putida (ATCC 17484) and Pseudomonas putida (ATCC 23973) for toluene removal were used simultaneously. The empty bed residence time (EBRT) ranged from 60 - 120 seconds and the inlet feed concentration was $0.0325\;g/m^3-0.0651\;g/m^3$ for $NH_3$, $0.0636\;g/m^3-0.141\;g/m^3$ for $H_2S$, and $0.0918\;g/m^3-0.383\;g/m^3$ for toluene, respectively. The observed removal efficiency was 2% - 98% for $NH_3$, 2% - 100% for $H^2S$, and 2% - 80% for toluene, respectively. Maximum elimination capacity was about $2.7\;g/m^3$/hr for $NH_3$, > $6.4\;g/m^3$/hr for $H_2S$ and $4.0\;g/m^3$/hr for toluene, respectively. The inorganic/polymeric composite carrier required 40 - 80 days of wetting time for biofilm formation due to the hydrophobic nature of the carrier. Once the surface of the carrier was completely wetted, the microbial activity became stable. During the long-term operation, pressure drop was negligible because the void volume of the carrier was two times higher than the conventional packing materials.

• The Korean Journal of Ecology
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• 제28권6호
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• pp.347-351
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• 2005

The amounts of organic carbon and several nutrients in litterfall on the forest floor of Quercus mongolica forest were assessed for two years from 1998 through 2000 in Mt. Songnisan National Park in Korea. The amounts of organic carbon (C) in litterfall were the highest in autumn with the values of $150.4g/m^2$ (62.6%) in 1998 and $219.2g/m^2$ (61.0%) in 1999. In winter, organic C was the lowest with the values of $16.3g/m^2$ (6.8%) in 1998 and $12.5g/m^2$ (6.7%) in 1999. It was estimated that the organic C added to forest floor via litterfall was 240.1 $g{\cdot}m^{-2}yr^{-1}$ and 186.6 $g{\cdot}m^{-2}yr^{-1}$ 1998 and 1999, respectively. The amounts of nitrogen (N) in litterfall were the highest in autumn with the values of 5.9 $g/m^2$ (58.0%) in 1998 and 5.2 $g/m^2$ (62.3%) in 1999. The amount of phosphorus (P) in litterfall showed its peak in autumn with 0.19 $g/m^2$ (52.9%) in 1998 and 0.11 $g/m^2$ (52.6%) in 1999. The amount of P returned to forest floor via litterfall was 0.35 $g{\cdot}m^{-2}yr^{-1}$ in 1998 and 0.22 $g{\cdot}m^{-2}yr^{-1}$ in 1999. The amount of potassium (K) in litterfall showed its peak in autumn with 0.57 $g/m^{2}$ (53.8%) in 1998 and 0.42 $g/m^2$ (55.3%) in 1999. The amounts of K returned to forest floor via litterfall was 1.11 $g{\cdot}m^{-2}yr^{-1}$ in 1998 and 0.81 $g{\cdot}m^{-2}yr^{-1}$ in 1999.

• KSBB Journal
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• 제26권5호
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• pp.439-442
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• 2011

1,2-propanediol (1,2-PD) is a commodity chemical that is currently produced from petrochemical derivatives. Saccharomyces cerevisiae is well characterized and a successful industrial microorganism to enable the improvement of the 1,2-propanediol production by metabolic engineering. A recombinant S. cerevisiae M3G3 was used to produce 1,2-propanediol. S. cerevisiae M3G3 is the diploid strain that contains 3 copies of mgs (methylglyoxal synthase) and gldA (glycerol dehydrogenase). S. cerevisiae M3G3 was cultivated at various culture conditions by changing culture temperature, glucose concentration, and inducer concentration. Also the effect of induction time was studied to optimize the production of 1,2-propanediol. Batch and fed-batch cultivation of S. cerevisiae M3G3 was performed by using a 5 L jar fermenter. The highest concentration of 1,2-propanediol in batch cultivation was 0.86 g/L and it was further improved to 1.33 g/L in fed-batch cultivation.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 봄 학술발표회 발표논문집
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• pp.328-331
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• 2003

1) PM10의 질량농도는 평균 98.21 ${\mu}g$/$m^3$로 나타났으며, 최고농도는 330.56 ${\mu}g$/$m^3$로서 연간 기준치인 80 ${\mu}g$/$m^3$를 초과하였다. 또한 K(1.23 ${\mu}g$/$m^3$)>Ca(1.12 ${\mu}g$/$m^3$)>Na(0.79 ${\mu}g$/$m^3$)>Al(0.76 )>Fe(0.75 ${\mu}g$/$m^3$) 순으로서 높은 조성을 보였으며, Cd(2.72 ng/$m^3$)이 가장 낮은 질량 농도를 보였다. 2) Cd, Ni, Pb 및 Zn은 평균 지각농축계수가 10이상의 인위적인 기원으로 봄철과 여름철에 비하여 서풍계열의 바람이 우세한 겨울철에 매우 높은 값을 보였으며, 연구 지역의 서쪽에 인접한 사상공단과 서남쪽에 위치한 신평.장림공단으로부터 서풍계열의 바람을 타고 이동되었음을 알 수 있었다. 또한 이들 중금속은 조대입자보다는 미세입자의 조성에 많은 영향을 미치는 것으로 나타났으며, 평균 토양입자의 기여율은 9.5%로 나타났다. 3) PM10의 조성에 관여하는 금속 원소들은 토양, 해양 및 인위적인 오염물질에 의한 기원을 동시에 포함하고 있으나 해양기원보다는 토양 및 인위적인 기원들 간의 상관성이 우세하게 나타났다.

• BMB Reports
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• 제40권6호
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• pp.899-910
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• 2007

Extracellular Regulated Kinases (ERK) and Protein Kinase B (Akt) are intermediaries in relaying extracellular growth signals to intracellular targets. Each pathway can become activated upon stimulation of G protein-coupled receptors mediated by $G_q$ and $G_{i/o}$ proteins subjected to regulation by RGS proteins. The goal of the study was to delineate the specificity in which cardiac RGS proteins modulate $G_{q^-}$ and $G_{i/o}$-induced ERK and Akt phosphorylation. To isolate $G_{q^-}$ and $G_{i/o}$-mediated effects, we exclusively expressed muscarinic $M_2$ or $M_3$ receptors in COS-7 cells. Western blot analyses demonstrated increase of phosphorylation of ERK 1.7-/3.3-fold and Akt 2.4-/6-fold in $M_{2^-}/M_{3^-}$ expressing cells through carbachol stimulation. In co-expressions, $M_3/G_q$-induced activation of Akt was exclusively blunted through RGS3s/RGS3, whereas activation of ERK was inhibited additionally through RGS2/RGS5. $M_2/G_{i/o}$ induced Akt activation was inhibited by all RGS proteins tested. RGS2 had no effect on $M_2/G_{i/o}$-induced ERK activation. The high degree of specificity in RGS proteins-depending modulation of $G_{q^-}$ and $G_{i/o}$-mediated ERK and Akt activation in the muscarinic network cannot merely be attributed exclusively to RGS protein selectivity towards $G_q$ or $G_{i/o}$ proteins. Counter-regulatory mechanisms and inter-signaling cross-talk may alter the sensitivity of GPCR-induced ERK and Akt activation to RGS protein regulation.

• 한국대기환경학회지
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• 제11권2호
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• pp.179-184
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• 1995

This study was carried out to characterize sources of suspended particulate matter(SPM) in Mt. Soback area from January to Novembver in 1993. The collection and major water soluble ion analysis of SPM were conducted by using a High Volumn Air Sampler(HVAS; W&A Inc., PM-10) and ion chromatograph(DIONEX 4000i), respectively. The variations of SPM and major ion concentrations were found to be 9. sim. 156.mu.g/ $m^{3}$, $F^{-10}$ 0.00 .sim. 0.15.mu.g/ $m^{3}$, C $l^{-10}$ 0.06 .sim. 3.79.mu.g/ $m^{3}$, N $O_{3}$$^{-10}$ 0.90 .sim. 6.85.mu.g/ $m^{3}$, S $O_{4}$$^{2-}$ 1.99 .sim. 9.36.mu.g/ $m^{3}$ N $a^{+}$0.00 .sim. 0.27.mu.g/ $m^{3}$, N $H_{4}$ $^{+}$0.72 .sim. 5.77.mu.g/ $m^{3}$, $k^{+}$0.03 .sim. 0.88.mu.g/ $m^{3}$ and $Ca^{2+}$0.12 .sim. 2.76.mu.g/ $m^{3}$. Tree sources were identified by Principal Component Amalysis(PCA) using a SPSS/P $C^{+}$. The explanation ability of forst, second and third Principal Component were 60.8%, 13.6%, 8.2%, of total variance. The sources classfied by PCA were found to be secondary aerosol/fuel combustion, soil dust related cement production/yellow sand and aerosol related waste burning.related waste burning.g.

• 한국어병학회지
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• 제18권3호
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• pp.269-276
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• 2005

본 실험에서 잉어를 대상으로 CPF, NRF 및 OXA등의 약제를 어체당 20 mg/kg 현탁액을 경구투여 후에 1-96 시간 경시적으로 약물의 동태를 조사 하였다. 각 약제별 최고장기농도도달시간은 간장 (8 h), 혈액 (12 h), 신장(12 h) 및 근육 (24 h) 이었다. 각 약제별 최대농도는 CPF (13.8-19.6 ${\mu}g$/$m\ell$), NRF (11.8-15.9 ${\mu}g$/$m\ell$), 및 OXA (10.8-13.9 ${\mu}g$/$m\ell$)순으로 나타났다. 약제농도는 최고치의 도달 이후 빠르게 소실되다가 48-96 h는 완만한 감소를 보였으며, 이때 장기별 약제농도는 근육 (3.3-6.3 ${\mu}g$/$m\ell$)> 간장 (2.5-5.5 ${\mu}g$/$m\ell$)> 신장 (2.3-4.2 ${\mu}g$/$m\ell$) > 혈장 (2.1-3.0 ${\mu}g$/$m\ell$)순으로 나타났다. 한편, OXA의 경우 다른 약제에 비해서 약물의 정체기가 나타났다. 즉 혈중은 12-36 h;, 고농도저류대 (24 hr; 10.9-8.8 ${\mu}g$/$m\ell$), 근육은 36-96 h에 중간농도대 (60 hr; 8.5-5.8 ${\mu}g$/$m\ell$) 및 간장은 12-96 h에 저농도대 (84 hr; 6.8-3.3 ${\mu}g$/$m\ell$)등이 형성되었다.약제의 혈중농도에 대한 각 장기농도비 (간장;L, 신장;K, 및 근육;M / 혈액;B)는 시간대에 따라 차이를 보였다. CPF는 즉 L>K>M (0.65-1.2/0.82-0.93/1.0-1.7)순으로 시간대별로 차이가 없었다. NRF는 시간대별로 1-8 h 및 12-24 h L>K>M (0.65-1.3/0.86-1.0)순이었으나, 36 h 이후 L>M>K (0.89-1.26)순이었다. OXA의 있어서는 1-8 h에는 L>K>M (0.95-2.1), 12-36에는 M>K>L (0.51-1.0) 및 48-96 h에는 M>L>K (1.0-2.3)으로 나타났다.

• Journal of applied mathematics & informatics
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• 제10권1_2호
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• pp.27-40
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• 2002

For two integers m, n with m $\leq$ n, an [m,n]-factor F in a graph G is a spanning subgraph of G with m $\leq$ d$\_$F/(v) $\leq$ n for all v ∈ V(F). In 1996, H. Enomoto et al. proved that every 3-connected Planar graph G with d$\_$G/(v) $\geq$ 4 for all v ∈ V(G) contains a [2,3]-factor. In this paper. we extend their result to all 3-connected locally finite infinite planar graphs containing no unbounded faces.

• Toxicological Research
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• 제13권3호
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• pp.203-208
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• 1997

The antigenic potential of M3S tumor necrosis factor-$\alpha$(M3S TNF), which is a mutated form of TNF(TNF mutein) designed to reduce adverse effects of wild type human TNF, was investigated in the present study. The antigenicity of M3S TNF was examined by conducting active systemic anaphylaxis (ASA) test in guinea pigs, heterologous(mouse-rat) passive cutaneous anaphylaxis(PCA) test and passive hemagglutination(PHA) test. The experimental animals were divided into low, medium, high and the highest dose groups and the groups with or without immunoadjuvant, sensitized according to the appropriate schedule and challenged. In ASA test, when challenged with 120 $\mu\textrm{g}$ /animal, moderate to severe positive anaphylactic responses were observed in groups sensitized with 12 $\mu\textrm{g}$ /animal, 120 $\mu\textrm{g}$ /animal and 120 $\mu\textrm{g}$ /animal+Freund's complete adjuvant. In PCA test, positive responses were observed in the group sensitized with the highest dose emulsified with an alum(12 $\mu\textrm{g}$ /animal+alum). In PHA test, positive responses were observed in the group sensitized with 3 $\mu\textrm{g}$ /animal emulsified with an alum. All the other groups in each experiment showed negative responses. Based on these results, M3S TNF is considered to have some antigenic potential.

• 분석과학
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• 제20권6호
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• pp.453-459
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• 2007

신축공동주택의 실내공기질에 영향을 미치는 휘발성유기화합물 및 카보닐화합물의 농도와 입주 후 거주기간에 따른 오염도 변화추이를 파악하고자 입주 후 신축 공동주택 120세대를 대상으로 실내공기 오염도를 조사하였다. 신축 공동주택 입주 후 TVOC (Total Volatile Organic Compounds; TVOCs)평균농도는 $688.61{\mu}g/m^3$으로 나타났으며, 포름알데히드, 톨루엔, m, p-자일렌, 아세톤, 에틸벤젠이 $158.56{\mu}g/m^3$, $146.58{\mu}g/m^3$, $69.28{\mu}g/m^3$, $63.80{\mu}g/m^3$, $29.65{\mu}g/m^3$의 순으로 높게 나타났다. 또한, 대부분의 실내오염물질들은 입주 후 거주기간이 증가함에 따라 평균농도가 감소하는 경향을 나타내었으나, d-리모넨의 경우 입주 후 2개월에서 10개월까지 지속적으로 증가하는 것으로 나타났다. 또한, 톨루엔, 에틸벤젠, m, p, o-자일렌 등의 주요오염물질이 전체 VOCs에서 차지하는 비율은 38.8%로 나타났으며, 거주기간에 증가함에 따라 구성비율이 감소하는 것으로 나타났다.