• 한국해양학회지:바다
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• 제9권4호
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• pp.196-203
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• 2004

한강 기수역에서 일어나는 지화학적 변화과정을 파악하기 위하여 2000년 6월과 2001년 2월 두 차례에 걸쳐 용존 무기영양염류,용존 유기 탄소,추출된 용존 유기물의 형광 특성, 용존 우라늄의 분포특성에 대해서 연구하였다. 용존 무기 영양염류는 염분이 증가함에 따라 감소하였는데,특히 질소계 영양염류의 경우 기수역에서 뚜렷한 질산화 과정(nitrification process)을 보였다. 인산-인 또한 질소계 영양염류와 같이 기수역에서 비보존적 분포특성을 보였다 용존 유기탄소와 형광 유기물은 염분이 증가함에 따라 감소하는 모습을 보였는데, 특히 5 psu이하의 저염분대에서 급격히 감소하는 양상을 나타내었다. 이러한 현상은 육상 기원의 지구거대 유기물질이 이온강도가 증가하는 기수역에서 응집, 침전하여 제거되기 때문으로 생각된다. 한편 용존 우라늄은 대부분 강을 통하여 해양으로 유입되는데, 염분이 증가함에 따라 같이 증가하는 양의 상관관계를 보였다. 용존 우라늄은 기수역에서 제거되는 비보존적인 분포 특성을 보였는데. 이는 용존 우라늄의 일부가 유기물질과 착화합물의 형태로 제거되기 때문으로 생각된다. 염분과 용존 우라늄의 분포 상관관계로부터 추정된 한강 기수역에서 용존 우라늄 제거량은 약 7.1 ton/year으로 Savannah salt marsh에서의 제거량과 비교해볼 때 약 51.4%에 해당하였다.

• 청정기술
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• 제15권3호
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• pp.154-164
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• 2009

2007년을 기준으로 울산에 위치한 사업장으로부터 발생된 유기성 폐수슬러지의 94%가 해양처분되었다. 유기성 슬러지의 해양처분은 2012년에는 완전 금지될 예정이다. 그러나 아직까지 울산에 위치한 사업장으로 부터의 유기성 슬러지는 소각 이외에 다른 대안이 없는 실정이며, 현재 울산석유화학산업단지의 사업장들은 슬러지의 육상처리 및 처분기술의 확보가 매우 중요한 과제이다. 본 연구에서는 울산의 석유화학사업장 슬러지와 하수처리 슬러지를 연료로 활용하기 위해 건조슬러지와 탄화슬러지의 재료적 측면에 대한 평가를 실시하였다. 연구결과 저위발열량 3,000 kcal/kg이상을 초과하는 테레프탈산, BTX, 프로필렌, 화학섬유 등을 생산하는 사업장으로부터의 건조슬러지와 탄화슬러지는 연료로서의 가능성이 높지만 건조할 경우 2,100 kcal/kg 이하, 탄화할 경우 1,100 kcal/kg 이하인 좀 더 무기성분이 많은 펄프, 제지, 메틸아민, 아마이드 등을 생산하는 사업장의 폐수슬러지는 연료로서의 가치가 적은 것으로 나타났다. 연구결과 대부분의 슬러지들이 에너지 측면에 있어서 탄화보다는 건조가 더 좋은 결과를 보여주었다.

• 공업화학
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• 제35권4호
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• pp.335-340
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• 2024

본 논문에서는 UIO-66에 항체 기능성을 도입한 유무기 하이브리드 소재를 합성하고 이를 표면 플라즈몬 공명(surface plasmon resonance, SPR) 분석법에 접목하여 옥시토신과 같은 작은 분자를 검출하는 감도를 향상시키고자 하였다. 옥시토신은 암, 알츠하이머, 심부전증 진단에 중요한 생물학적 표지 펩타이드 분자로 알려져 있으며, 이를 수 펨토몰(femtomole, fM) 농도 수준까지 검출하기 위해 다공성이며 표면적이 우수한 metal organic frameworks 중 하나인 UiO-66-(COOH)₂ 소재를 신호증폭용으로 활용하면서 옥시토신에 특이적인 항체 페어를 이용하는 표면 샌드위치 분석법을 개발함으로써 선택성을 향상시키고자 하였다. 이를 위해 먼저 선정한 각 옥시토신 특이적 항체가 옥시토신에 대해 강하게 결합하는지 그리고 각 항체가 옥시토신의 서로 다른 결합사이트에 결합하는지를 실시간 SPR 분석법으로 확인하였다. 선정한 항체 중 한 개(예: anti-OXT [OTI5G4])를 SPR용 금 박막 칩 표면에 고정하고, 옥시토신을 흘려준 후, UiO-66-(COOH)₂에 컨쥬게이션된 다른 항체(예: anti-OXT[4G11])를 순차적으로 흘려주어 표면에 샌드위치 복합체(anti-OXT[OTI5G4]/옥시토신/UiO-66-(COOH)₂-anti-OXT[4G11])를 형성하였을 때 옥시토신 농도에 따라 SPR 신호가 변화하는 것을 실시간으로 모니터링하였다. 그 결과, UiO-66-(COOH)₂를 사용하지 않았을 때 대비 약 백만 배 이상 감도를 증폭시켜 약 10 fM까지 검출 가능함을 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권12호
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• pp.1717-1724
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• 2004

The study was conducted to determine the effect of Salmonella typhymurium lipopolysaccharide (LPS) challenge on egg-laying performance, inflammatory response, zinc metabolism in layer fed diets supplemented with organic or inorganic zinc since 3-wk-old. The three dietary treatments were corn-soybean meal basal diet without supplemental zinc or with supplemental zinc at 60 mg/kg zinc from $ZnSO_4$ or zinc amino acid complex (ZnAA). At the age of 58 wk-old, twelve hens from each dietary treatment were allotted into two sub-groups. On day 1, 3, 5, 7 of the $58^{th}$ week of age, six birds of one sub-group were injected intraperitoneally (i.p.) with 2 ml LPS (1.0 $\ell$/ml) or sterile saline. Neither zinc source ${\times}$ immune challenge interaction nor zinc source effect on egg production performance was observed (p>0.05), LPS-challenge decreased egg production (p<0.04) and increased percentage of cracked eggs (p <0.01). With LPS challenged, the fever response of hens fed ZnAA peaked and subsided earlier than in hens fed $ZnSO_4$ or basal diet. Serum IL-1$\beta$ at 3 h was higher (p<0.01), but lower (p<0.001) at 12 h post-challenge with LPS in hens fed ZnAA than $ZnSO_4$. In salinetreated groups, serum IL 1$\beta$ was higher in hens fed ZnAA than the basal diet at 3 h post-injection (p<0.01). LPS-challenged birds had lower serum zinc and higher zinc sequestered in liver and spleen (p<0.001). In saline-treated birds, there was no difference in zinc concentration of serum, liver and spleen among different dietary treatments (p>0.05). Supplementation of 60 mg/kg zinc from either ZnAA or $ZnSO_4$ significantly (p<0.05) elevated metallothionein (MT) concentration in liver and spleen. MT concentration in liver of birds fed ZnAA diet was higher than in those fed $ZnSO_4$ diet (p<0.05). The magnitude of increase of hepatic and splenic MT due to LPS challenge was higher by supplementation of ZnAA than $ZnSO_4$. The results suggest that zinc amino acid complex enhanceed MT synthesis and zinc sequestered in liver and spleen and increased the sensitivity to immune response due to LPS challenge.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권1호
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• pp.49-58
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• 2017

Biotic ligand model (BLM) and species sensitivity distribution (SSD) were used to determine the site-specific Cu threshold concentration (5% hazardous concentration; HC5) in soil pore water. Model parameters for Cu-BLM were collected for six plants, one collembola, and two earthworms from published literatures. Half maximal effective concentration ($EC_{50}\{Cu^{2+}\}$), expressed as $Cu^{2+}$ activity, was calculated based on activities of major cations and the collected Cu-BLM parameters. The $EC_{50}\{Cu^{2+}\}$ varied from 2 nM to $251{\mu}M$ according to the variation in environmental factors of soil pore water (pH, major cation/anion concentrations) and the type of species. Hazardous activity for 5% (HA5) and HC5 calculated from SSD varied from 0.076 to $0.4{\mu}g/L$ and 0.4 to $83.4{\mu}g/L$, respectively. HA5 and HC5 significantly decreased with the increase in pH in the region with pH less than 7 due to the decrease in competition with $H^+$ and $Cu^{2+}$. In the region with pH more than 7, HC5 increased with the increase in pH due to the formation of complexes of Cu with inorganic ligands. In the presence of dissolved organic carbon (DOC), Cu and DOC form a complex, which decreases $Cu^{2+}$ activity in soil pore water, resulting in up to 292-fold increase in HC5 from 0.48 to $140{\mu}g/L$.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2002년도 추계학술대회
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• pp.720-720
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• 2002

A number of investigations have shown that the presence of bacteria is prerequisite for developing pulpal and/or periradicular pathosis. Depending on the stage of pulpal pathosis, various species of bacteria can be cultured from infected root canals. Kakehashi et al. showed that exposure of pulpal tissue in germ-free rats was characterized by minimal inflammation and dentinal bridging while exposure of pulpal tissue in conventional rats with normal oral flora was characterized by pulpal necrosis, chronic inflammation, and periapical lesions. Currently used methods of cleaning and shaping, especially rotary instrumentation techniques, produce a smear layer that covers root canal walls and the openings to the dentinal tubules. The smear layer contains inorganic and organic substances that include fragments of odontoblastic processes, microorganisms, their by products and necrotic materials. Because of its potential contamination and adverse effect on the outcome of root canal therapy, it seems reasonable to suggest removal of the smear layer for disinfection of the entire root canal system. Presence of this smear layer prevents penetration of intracanal medications into the irregularities of the root canal system and the dentinal tubules and also prevents complete adaptation of obturation materials to the prepared root canal surfaces. Removal of the smear layer by an intracanal irrigant and placement of an antibacterial agent in direct contact with the content of dentinal tubules should allow disinfection of this complex system and better outcome for the root canal therapy. A new solution, which was a mixture of a tetracycline, an acid, and a detergent(MTAD), was developed in the Department of Endodontics, Dental School. Lorna Linda University, USA. It has been demonstrated that MTAD was an effective solution for the removal of the smear layer and does not significantly change the structure of the dentinal tubules when used as a final irrigant in conjunction with 1 % NaOCl as a root canal irrigant. Studies are in progress to compare the anti- microbial properties of this newly developed solution with those of sodium hypochlorite and EDTA that are currently used to irrigate the root canals and remove the smear layer from the surfaces of instrumented root canals.canals.

• 한국환경보건학회지
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• 제24권3호
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• pp.63-69
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• 1998

The treatment of soils and water contaminated with MTBE using the Fenton oxidation was investigated. The effects of dosage of $H_{2}O_{2}$, and Fe$^{2+}$ concentrations, and solution pH on transformation and mineralization in soil were evaluated. Generation of TBA and acetone following Fenton-oxidation of MTBE in water and generation of acetone following Fenton-oxidation of TBA were observed. Therefore TBA and acetone are degradation intermediates of MTBE. There was a large difference of treatment efficiency in Fenton oxidation of MTBE between soil and water system. This may be caused by the complex nature of soil, soil organic matter which can consumed OH $\cdot$ radicals, and interacting with inorganic-soil constituents. The pH of soil was observed to have a significant effect on the chemical oxidation efficient of MTBE in soil The data demonstrated that optimal pH range were pH 3~4 and around 6. The soil batch studies demonstrated that treatment efficiency of MTBE was enhanced by adding additional ferrous salts but Fenton-oxidation occurred in no additional iron which indicated that iron in soil can catalyze the Fenton-oxidation. The most effective parameter of Fentonoxidation was $H_{2}O_{2}$/Fe$^{2+}$ ratio which theocratical ratio is 0.5. The optimal range of this ratio was found to be 0.6~2.3. In evaluating effect of $H_{2}O_{2}$ dosage on treatment efficiency, the increase of $H_{2}O_{2}$ did not always lead to increase of decompositions of MTBE in soil. Fenton oxidation was effective in destroying MTBE in aqueous extracts of contaminated soil and water. Experimental data provided evidence that the Fenton oxidation can effectively remediate MTBE-contaminated water and soil.

• Journal of Dairy Science and Biotechnology
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• 제33권4호
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• pp.271-275
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• 2015

Colloidal semiconductor CdSe-ZnS core-shell nanocrystal quantum dot (Qdot) are luminescent inorganic fluorophores that show potential to overcome some of the functional limitations encountered with organic dyes in fluorescence labeling applications. Salmonella Enteritidis has emerged as a major cause of human salmonellosis worldwide since the 1980s. A rapid, specific, and sensitive method for the detection of Salmonella Enteritidis was developed using Qdot as a fluorescence marker coupled with immunomagnetic separation. Magnetic beads coated with anti-Salmonella Enteritidis antibodies were employed to selectively capture the target bacteria, and biotin-conjugated anti-Salmonella antibodies were added to form sandwich immune complexes. After magnetic separation, the immune complexes were labeled with Qdot via biotin-streptavidin conjugation, and fluorescence measurement was carried out using a fluorescence measurement system. The detection limit of the Qdot method was a Salmonella Enteritidis concentration of $10^3$ colony-forming units (CFU)/mL, whereas the conventional fluorescein isothiocyanate-based method required over $10^5CFU/mL$. The total detection time was within 2 h. In addition to the potential for general nanotechnology development, these results suggest a new rapid detection method of various pathogenic bacteria from a complex food matrix.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.217-219
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• 2006

This study focused an water quality response to land-based pollution loads and the appropriate pollutant load reduction in Chinhae Bay using an eco-hydrodynamic model. Land-based discharge foam urban areas, industrial complex and sewage treatment plant was the greatest contributor to cause red-tide blooms and summer hypoxia. Tidal currents velocity af the ebb tide was about 10 cm/s stronger than that of the flood tide. A residual current was simulated to. have a slightly complicated pattern with ranging from 0.1 to. 2.7 cm/s. In Masan Bay, pollutant materials cannot flaw from the inner to the outer bay easily because af residual currents flaw southward at surface and northward at the bottom. The simulation results of COD distribution showedhigh concentrations aver 3 mg/L in the inner part of Masan Bay related pollutant discharge, and charge, and lower levels less than 1.5mg/L in the central part of Chinhae Bay. For improvement water quality in Chinhae Bay, it is necessary to reduce the organic and inorganic loads from paint sources by mare than 50% and ameliorate severe polluted sediment.

• 한국환경보건학회지
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• 제33권6호
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• pp.479-487
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• 2007

[ $PM_{2.5}$ ], particulate matter less than 2.5 um in a diameter, can penetrate deeply into the lungs. Exposure to $PM_{2.5}$ has been associated with increased hospital visits for respiratory aliments as well as increase mortality. $PM_{2.5}$ is a byproduct of combustion processes and as such has a complex composition including a variety of metallic elements, inorganic and organic compounds as well as biogenic materials (microorganisms, proteins, etc). In this study, the average concentrations of fine particulates $PM_{2.5}$ have been measured simultaneously in Asan and Seoul, Korea, by using particulate matter portable sampler from September 2001 to August 2002. Sample collection filters were analyzed by ICP-OES to determine the concentrations of metallic elements (As, Ni, Fe, Cr, Cd, Cu, Pb, Zn, Si). Annual mean $PM_{2.5}$ concentrations in Asan and Seoul were 37.70 and $45.83\;{\mu}g/m^3$, respectively. The highest concentrations of $PM_{2.5}$ were found in spring season in both cities and the concentrations of measured metallic elements except As in Asan were higher than those in Seoul, suggesting that yellow dust in spring could affect $PM_{2.5}$ concentrations in Asan rather than Seoul. The correlation coefficients of Pb and Zn were 0.343 for Asan and 0.813 for Seoul during non-yellow dust condition, suggesting that Pb and Zn were influenced with the same sources. The correlation coefficients between Si and Fe in the fine particulate mode were 0.999 (Asan) and 0.998 (Seoul) during yellow dust condition. It was suggested that these two elements were impacted by soil-related transport from China during the yellow dust storm condition.