• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.35-41
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• 2009

This study was conducted to investigate feasibility of feedstuff for animal using food waste by fermentation mechanism of indigenous microorganism. To achieve this purpose, indigenous bacteria was isolated from soils to use as an inoculant. Enzyme test was performed to verify activity of amylase, protease and lipase using isolated bacteria. Bacteria(H1, D1), which vigorously express the enzyme activity, was selected and used in the fermentation experiments of food waste. From the analysis of 16s rDNA sequencing, H1 and D1 were identified as Bacillus subtilis and Paenibacillus polymyxa, respectively. In the fermentation experiment, food waste was mixed with rice bran and popped rice to control moisture and nutrient content. Isolated bacteria(B. subtilis and P. polymyxa) was used as an inoculant. From the measured data such as temperature, pH and ORP, it can be verified that food waste adding the indigenous bacteria was effectively fermented. From the nutritional analysis of manufactured feedstuff, it showed that the contents of crude protein, crude fat and crude fiber were enough to use as feedstuff for animal. In addition, harmful components such as Pb, Hg, Cd, aflatoxin and salmonella concentration were not exceeded permitted standards. Therefore, fermented food waste using indigenous bacteria can be used as feedstuff.

• Journal of the Korean Magnetic Resonance Society
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• v.3 no.2
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• pp.100-108
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• 1999

Cop protein is the transcription repressor protein in rolling circle replication plasmid. With antisense RNA, Cop protein controls the copy number of plasmid. Cop family proteins have been found in various plasmids. Among Cop family proteins, Cop studied in this paper consists of 55 amino acids (Mw. 6,400), and was known to have trimer structure. Since no structural facts are elucidated, we have carried out preliminary experiments aimed at the elucidation of its three dimensional structure. The secondary structure of Cop is studied by CD and NMR. To solve the aggregation of Cop at high concentration, we tested various detergents and salts. The addition of detergents and salts could not solve the aggregation problem. However, we found that concentration is important in solving the aggregation problem. We knew that 0.18mM in 50mM potassium phosphate without any other ingredients is maximum concentration not to aggregate. Wa also investigated the pH dependence of Cop protein, and knew that Cop protein is more stable in acid state. At various temperatures, 15N-1H HSQC spectra were measured in order to find the optimal experimental condition. To enhance the peak resolution, 3D NOESY-HSQC spectrum is acquired. Since there are NOE peaks in the NH-NH region, we knew that Cop protein has $\alpha$-helical content, which was also confirmed by CD.

• Laser Solutions
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• v.7 no.3
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• pp.37-46
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• 2004

The shape and size variations of the nanopatterns produced on a polymer film using a near-field scanning optical microscope(NSOM) are investigated with respect to the process variables. A cantilever type nanoprobe having a 100nm aperture at the apex of the pyramidal tip is used with the NSOM and a He-Cd laser at a wavelength of 442nm as the illumination source. Patterning characteristics are examined for different laser beam power at the entrance side of the aperture($P_{in}$), scan speed of the piezo stage(V), repeated scanning over the same pattern, and operation modes of the NSOM(DC and AC modes). The pattern size remained almost the same for equal linear energy density. Pattern size decreased for lower laser beam power and greater scan speed, leading to a minimum pattern width of around 50nm at $P_{in}=1.2{\mu}W\;and\;V=12{\mu}m/s$. Direct writing of an arbitrary pattern with a line width of about 150nm was demonstrated to verify the feasibility of this technique for nanomask fabrication. Application on high-density data storage is discussed.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.113-122
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• 2007

Experimental studies were performed to investigate speciation and leaching potential of heavy metals(Cu, Cd, Pb Zn, Ni) in ten sediment samples collected from Nakdong River. Acid Volatile Sulfide (AVS) and Simultaneously Extractable Metals (SEM) measurements were used to estimate heavy metals that can be leached under anaerobic conditions. Sequential Extraction Procedure (SEP) and Toxicity Characteristic Leaching Procedure (TCLP) were used to characterize speciation and leaching potential of heavy metals under aerobic conditions. The results show that total concentrations of Cu, Zn and Ni were relatively high in the sediments from points Seongseo industrial complex stream (upper stream) (D), Seongseo industrial complex stream (midstream) (E), Dalseo stream (F), and Nakdong river estuary (J), and that Cd concentrations were higher in all sampling points except for Goriung Bridge (G) and Soosan Bridge (H). SEM and AVS analyses reveal that samples from points Ilsun Bridge (A), Namgumi Bridge (C), and Soosan Bridge (H) have potential of heavy metals leaching, although leachable concentrations are relatively low. The leaching potential of heavy metals in other points was low because of higher concentrations of AVS than SEM. SEP results show that more than 50% of Cu, Zn and Ni were present in residual fraction, which means these metals are less amenable to leaching in anaerobic conditions. On the other hand, more than 50% of Pb and Cd were extracted during the first through third step of the SEP, which means substantial fraction of these metals can be leached upon changing of redox conditions. TCLP tests predict that leaching potential of heavy metals was generally low, which is consistent with the results obtained by AVS and SEM measurements.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1415-1419
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• 2006

메탄을 탄소원 및 에너지원으로 이용하는 메탄산화균은 물질대사과정 중에 다량의 세포외 고분자물질인 Extracellular polymeric substances(EPS)를 생성하는데, EPS는 카르복실기와 같은 표면흡착 기능을 가지고 있어 생체흡착제로 사용이 가능하다. 따라서 본 연구에서는 메탄산화세균을 이용하여 중금속인 Cd의 흡착성능을 파악하여 활성슬러지의 흡착능과 비교하고, EPS 농도별, pH별 흡착량의 변화를 실험한 후 Freundlich 흡착모델식에 적용하여 흡착공정의 기본적인 설계인자를 도출하고자 하였다. 실험에 사용한 메탄산화세균은 매립지 복토층 상부 토양에서 분리하여 실험실에서 대량으로 배양하였으며, EPS 생성을 위해 메탄을 Head space의 20%를 주입하고 $30^{\circ}C$, 150rpm에서 질소원이 부족한 조건으로 48hr 동안 배양하였다. Cd의 흡착실험은 용액의 pH를 3에서 8까지 변화를 주면서 활성슬러지와 메탄산화세균의 시간별 흡착능을 측정하였다. 또한 중금속의 농도별 흡착능을 측정하여 흡착평형 상수를 파악하였으며, 중금속 흡착 전, 후 미생물의 SEM 촬영, FT-IR 분석, 전자현미분석(EPMA)을 통하여 무기성분 분석 및 표면관찰을 수행하였다. 실험결과 메탄산화세균에 의해 생성된 EPS 물질은 중금속에 대한 강한 결합능력이 있으며, Cd에 대한 최고 흡착능은 26mg Cd(Ⅱ)/g VSS의 값을 보였다. 이러한 미생물의 EPS의 흡착능은 pH와 칼슘이온의 영향을 많이 받았으며, 메탄산화세균의 FT-IR 분석결과 EPS에는 sulfate ester, pyruvate 등과 같은 작용기와 amino sugar, carboxyl 작용기들이 많이 존재하여 활성슬러지에 비해 중금속의 흡착능이 높은 것으로 사료되었다.X>${\mu}_{max,A}$는 최대암모니아 섭취률을 이용하여 구한 결과 $0.65d^{-1}$로 나타났다.EX>$60%{\sim}87%$가 수심 10m 이내에 분포하였고, 녹조강과 남조강이 우점하는 하절기에는 5m 이내에 주로 분포하였다. 취수탑 지점의 수심이 연중 $25{\sim}35m$를 유지하는 H호의 경우 간헐식 폭기장치를 가동하는 기간은 물론 그 외 기간에도 취수구의 심도를 표층 10m 이하로 유지 할 경우 전체 조류 유입량을 60% 이상 저감할 수 있을 것으로 조사되었다.심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전

• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.3-10
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• 1993

Polycrystalline CdS thin films were grown on ceramic substrate using a chemical bath deposition method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study CdS polycrystal structure. Using extrapolation method of X-ray diffraction patterns for the CdS samples annealed in $N_{2}$ gas at $550^{\circ}C$ it was found hexagonal structure whose lattice constants $a_{o}$ and $c_{o}$ were $4.1364{\AA}$ and $6.7129{\AA}$, respectively. Its grain size was about $0.35{\mu}m$. Hall effect on this sample was measured by Van der Pauw method and studied on carrier density and mobility defending on temperature. From Hall data, the mobility was likely to be decreased by piezo electric scattering at temperature range of 33K and 150k and by polar optical scattering at temperature range of 150K and 293K. We measured also spectral response, sensitivity (${\gamma}$), maximum allowable power dissipation and response time on these samples.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.194-203
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• 2005

This study was peformed to investigate effect of feeding experimental mixture containing chitosan, hibiscus extract and L-carnitine on body weight and lipid metabolism in rats. Forty-eight male rats(Charles River CD) of eight weeks old and weighing $336.5{\pm}2.3g$ were raised for five weeks with high fat diet(40% fat as calorie) to induce obesity. After induction of obesity, rats weighing $560.4{\pm}5.6g$ were blocked into four groups according to body weight and raised for eight weeks with diet containing either 0.09%(+1D group), 0.9%(+10D group) or 4.5%(+50D group) of experimental mixture. Aspartate aminotransferase(AST) and alanine aminotransferase(ALT), total protein and albumin were normal levels in plasma. Body weight gain and epididymal fat pad weight were lower in experimental mixture groups than control group However, weights of perirenal fat pad and brown adipose tissue were not significantly different among all groups. There was no significant difference in plasma and hepatic lipid levels among all groups. Liver citrate lyase and camitine acyltransferase activities were not significantly different among all groups, however, citrate lyase activity was tended to be decreased with increasing experimental mixture level in diet. Fecal total lipid and total cholesterol excretions were highest in +50D group, and triglyceride excretion was highest in +1D group. in conclusion, intake of experimental mixture containing chitosan, hibiscus extract and L-camitine was effective in reducing body weight and body fat, and its inhibitory effects might lead to obesity improvement.

• Natural Product Sciences
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• v.27 no.1
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• pp.49-53
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• 2021

Balanophora laxiflora Hemsl. (Balanophoraceae) is a traditional medicinal plant with a diverse array of biological activities. In our exploration of new bioactive constituents from B. laxiflora, we isolated five compounds, including a new lignan, balanophorone (5), and four known phenolic compounds (1-4). The chemical structures of these compounds were determined by extensive spectroscopic analyses, including 1D and 2D NMR, HR-ESI-MS, and CD. In addition, we evaluated the effects of each of the isolates (1-5) on the messenger RNA expression levels of tumor necrosis factor (TNF)-α and cyclooxygenase (COX)-2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells. Compound 2 showed significant inhibition of LPS-induced COX-2 and TNF-α expression in RAW 264.7 macrophages, while compound 4 showed moderate cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells, with IC50 values of 18.3 and 30.7 µM, respectively. No significant effects on the viability of normal mammary epithelial cells were observed.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3223-3228
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• 2011

To quantify the presence of mercuric ions in aqueous solution, double-stranded DNA (dsDNA) of poly(dT) was employed using a light switch compound, $Ru(phen)_2(dppz)^{2+}$ (1) which is reported to intercalate into dsDNA of a right-handed B-form. Addition of mercuric ions induced the dehybridization of poly(dT)${\cdot}$poly(dA) duplexes to form a hairpin structure of poly(dT) at room temperature and the metal-to-ligand charge transfer emission derived from the intercalation of 1 was reduced due to the dehybridization of dsDNA. As the concentration of $Hg^{2+}$ was increased, the emission of 1 progressively decreased. This label-free emission method had a detection limit of 0.2 nM. Other metal ions, such as $K^+$, $Ag^+$, $Ca^{2+}$, $Mg^{2+}$, $Zn^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Ni^{2+}$, $Cu^{2+}$, $Cd^{2+}$, $Cr^{3+}$, $Fe^{3+}$, had no significant effect on reducing emission. This emission method can differentiate matched and mismatched poly(dT) sequences based on the emission intensity of dsDNA.

• Korean Journal of Environmental Agriculture
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• v.39 no.1
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• pp.10-19
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• 2020

BACKGROUND: This study was to carry out risk assessment of contamination of cadmium (Cd), lead (Pb), and inorganic arsenic (I-As) in agricultural products of 25 crops from the abandoned mine areas. The 36 typical investigation sites located in Gyeongbuk provincial area were selected by considering the heavy metal levels, that had been known that the amount of the heavy metals exceeded the contamination level based on the previous survey. METHODS AND RESULTS: Cadmium, lead, and total arsenic (T-As) concentrations were determined using microwave device and ICP-MS. Inorganic arsenic was determined by HPLC-ICP-MS. The limits of quantification for heavy metals were 0.59 ㎍/kg for Cd, 0.42 ㎍/kg for Pb, 0.55 ㎍/kg for T-As, and sum of As (III) (1.74 ㎍/kg) and As (V) (2.25 ㎍/kg) for I-As, respectively. The contents of Cd, Pb, and I-As (only rice) were N.D.-0.958 mg/kg, N.D.-0.227 mg/kg, and 0.082 mg/kg, respectively, in the agricultural products. For risk assessment, dietary exposures of heavy metals through usual intake were 5.20×10^-4-7.15×10⁰ ㎍/day for Cd, 7.00×10^-5-7.75×10^-1 ㎍/day for Pb, and 1.17×10¹ ㎍/day for I-As, taking 0.01-14.37%, 0.01-2.05%, and 15.16% as risk indices, respectively. CONCLUSION: It requires to consider the critical levels of heavy metals in agricultural products due to unexpectedly high levels in a few places, while concentrations of heavy metals in the samples were relatively low in most areas.