• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.954-957
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• 1999

We have synthesized carbon nanotubes by thermal chemical vapor deposition of $C_2$H$_2$ on transition metal-coated silicon substrates. Carbon nanotubes are uniformly synthesized on a large area of the plain Si substrates, different from previously reported porous Si substrates. It is observed that surface modification of transition metals deposited on substrates by either etching with dipping in a HF solution and/or NH$_3$ pretreatment is a crucial step for the nanotube growth prior to the reaction of $C_2$H$_2$gas. We will demonstrate that the diameters of carbon naotubes can be controlled by applying the different transition metals.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.617-619
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• 2004

As an pretreatment, a Fe$(NO_3)_3{\cdot}9H_2O-Al(OH)_3$mixture was ground by a high energy mill and used as a supported catalyst for the growth of carbon nanotubes by a thermal CVD. The crystal structure of the catalyst disordered by the grinding influenced significantly the synthesis of carbon nanotubes in a thermal CVD.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.385-390
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• 2010

This study investigated the decomposition of fenitrothion in Smithion, which is applied on the golf course for pesticide, by the integrated Zero-valent iron(ZVI) and Granular activated carbon(GAC) process. First, the removal efficiencies of the fenitrothion by ZVI and GAC, respectively, were investigated. Second, the removal efficiencies of the fenitrothion by the integrated ZVI and GAC were investigated. The removal efficiencies of fenitrothion by ZVI were higher than those of TOC. The removal efficiencies of fenitrothion and TOC by GAC were similar. As the dosages of ZVI and GAC were increased, the removal efficiencies of fenitrothion and TOC increased. However, as the dosages of ZVI for pretreatment were increased, the adsorptions of fenitrothion on GAC were hindered.

• Journal of Yeungnam Medical Science
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• 제9권1호
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• pp.137-148
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• 1992

간에 괴사성 병변을 일으키는 사염화탄소의 독작용이 phenobarbital로 전처치한 경우 형태학적으로 어떤 영향을 받는가를 관찰하기 위해 먼저 체중 kg당 사염화탄소 0.4mg의 용량을 olive유에 20%로 희석하여 쥐의 복강내에 주입하였다. 그 다음 PB 전처치에 의한 영향율 조사하기 위해 전처치후 동량의 사염화탄소를 주입하였고 각각 투여후 6, 12, 24, 48, 72, 120 시간에 간조직을 적출하여 형태학적으로 관찰하여 다음과 같은 결과를 얻었다. 광학현미경하에서 사염화탄소 단독 투여시 6시간부터 소엽 중심부에 괴사성 병변이 나타나기 시작하여 48시간에 가장 심하였고, 72시간에는 회복되는 양상을 보였다. 괴사에 더하여 지방 변성, 수포성 변화가 심하게 동반되었다. PB 전처치시 6시간부터 괴사가 나타나기 시작하여 72시간까지 지속되었으며 그 정도도 더 심해졌다. 지방변성은 사염화탄소 단독투여군보다 더 심해졌고 수포성 변화는 감소되었다. 전자 현미경하에서 사염화탄소 단독 투여시 초기의 주된 변화는 내형질막의 덩어리 형성과 수포성 팽창이었고 PB 전처치시 이러한 내형질막의 변성 변화는 더 심하게 나타났으며 초기부터 사립체의 심한 변화를 동반하였다. 이상의 결과로 보아 사염화탄소의 간 독작용은 먼저 내형질막의 손상으로 시작하여, 이차적으로 다른 소기관에 손상이 수반되고 세포괴사가 나타나며, 이는 PB 전처치에 의해 악화됨을 알 수 있었다.

• Journal of Yeungnam Medical Science
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• 제8권2호
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• pp.84-94
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• 1991

간에 급성 출혈성 괴사를 일으키는 dimethylnitrosamine(DMN)의 간 독작용이 과량의 사염화탄소로 전처치시 어떤 영향을 받는 가를 관찰하기 위해 먼저 DMN을 쥐의 복강내에 주입하였다. 또 사염화탄소 전처치에 의한 영향을 조사하기 위해 사염화탄소 투여 후 DMN을 투여하고 간조직을 적출하여 광학 현미경 및 전자 현미경으로 관찰하였다. 광학 현미경하에서 DMN 단독 투여시 12시간부터 간 소엽중심부에 심한 출혈성 괴사가 나타나서 120시간까지 지속되었다. 과량의 사염화탄소로 전처치시 초기부터 광범위한 괴사가 나타났으나 24시간부터는 활발한 재생성변화가 나타나서 120시간에는 거의 정상으로 회복되어서 괴사의 정도는 DMN 단독 투여군과 유사하고 회복되는 시간은 단독 투여군보다 더 빨랐다. 전자 현미경하에서 DMN 단독 투여시 초기 변화는 주로 과립성 내형질막의 분열로 나타났고, 사염화탄소 단독 투여시는 내형질막의 덩어리 형성과 수포성 팽창으로 나타났다. 사염화탄소 전처치 후 DMN 투여시 초기에 나타난 변화는 그 양상이 사염화탄소 단독 투여시와 유사했지만 정도가 더 심했다. 이상의 결과에서 DMN의 급성중독 효과는 과량의 사염화탄소로 전처치한 경우에 재생이 더 빨리 이루어지는 것으로 보아 사염화탄소가 DMN에 대해 방어적인 작용을 하는 것으로 추측된다.

• 동의생리병리학회지
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• 제24권3호
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• pp.439-445
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• 2010

Pretreatment with Taraxacum Mongolicum H(TMH) prior to the administration of on $CCl_4$ significantly prevented the increased serum enzymatic activity of aminotransferase(ALT, AST), gamma-glutamyl transpeptidase(GGT) and bilirubin concentration in dose-dependent manner. In addition, pretreatment with TMH also significantly restored the elevation of hepatic malondialdehyde formation and the depletion of reduced glutathione content in the liver $CCl_4$-intoxicated rats. The restoration of microsomal aniline hydroxylase and aminopyrine N-demethylase activities indicated the improvement in functional status of endoplasmic reticulum. $CCl_4$-induced hepatotoxicity was also essentially prevented, as indicated by a liver histopathologic study. TMH showed antioxidant effects in $FeCl_2$-ascorbate-induced lipid peroxidation in rat liver homogenate and in superoxide radical scavenging activity. Our results suggest that the protective effect of TMH against $CCl_4$-induced hepatotoxicity possibly involve mechanisms related to its ability to block p450-mediated $CCl_4$ bioactivation and free radical scavenging effects.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.387-392
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• 2018

Various technical approaches and concepts have been proposed to develop conductive super-hydrophobic (SH) surfaces. However, most of these approaches are not usable in practical applications because of insufficient adhesion and cost issues. Additionally, durability and uniformity issues are still in need of improvement. The goal of this research is to produce a large-area conductive SH surface with improved adhesion performance and uniformity. To this end, carbon nanotubes (CNT) with a high aspect ratio and elastomeric polymer were utilized as a conductive filler and matrix, respectively, to form a coating layer. Additionally, nanoscale silica particles were utilized for stable implementation of the conductive SH surface. To improve the adhesion properties between the SH coating layer and substrate, pretreatment of the substrate was conducted by utilizing both wet and dry etching processes to create specific organic functional groups on the substrate. Following pretreatment of the surface, a zirco-aluminate coupling agent was utilized to enhance adhesion properties between the substrate and the SH coating layer. Raman spectroscopy revealed that adhesion was greatly improved by the formation of a chemical bond between the substrate and the SH coating layer at an optimal coupling agent concentration. The developed conductive SH coating attained a high electromagnetic interference (EMI) shielding effectiveness, which is advantageous in self-cleaning EMI shielding applications.

• 약학회지
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• 제45권1호
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• pp.78-84
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• 2001

Heme oxygenase is a rate-limiting enzyme in heme catabolism that cleaves heme to form biliverdin, iron, and carbon monoxide. Heme oxygenase-1 is expressed in many types of cells and tissues and is highly induced in response to oxidative stress. Carbon monoxide, one of the products of heme oxygenase, can stimulate soluble guanylate cyclase and dilate the vascular smooth muscle. So, the induction of heme oxygenase by lipopolysaccharide (LPS)-induced oxydative stress and the effect of the resultant carbon monoxide on aortic contractility were examined in this study. Zinc protoporphyrine IX (ZnPP), a inhibitor of heme oxygenase, elicited weak contraction of thoracic aortic ring, and this effect was more potent in aorta of LPS-treated rats than control and was blocked by methylene blue. The hyperreactivity to ZnPP in LPS-treated group was blocked by co-treatment with aminoguanidine. In the aortic ring of LPS-treated rats, ZnPP didn't change the vasoreactivity to phenylephrine or acetylcholine. ZnPP elicited hyper-tensive effect in concious rats, and pretreatment with LPS did not affect this effect. Prazosin significantly diminished the hypertensive effect of ZnPP. These results indicate that LPS induced heme oxygenase in aotra, and the resultant carbon monoxide diminished the aortic reactivity to vasoconstrictor.

• 한국지반환경공학회 논문집
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• 제15권10호
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• pp.15-21
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• 2014

본 연구는 부산시 남부하수처리장의 탈수슬러지를 이용하여 전처리에 따른 분해 및 혐기성 상태에서의 최종 메탄 및 이산화탄소 발생량을 평가하기 위해 Biochemical Methane Potential(BMP) 실험을 실시하였다. 초기 1 % TS 농도의 탈수슬러지를 각각 30분 동안 5M NaOH를 이용하여 알칼리 전처리를 실시하였고 초음파 전처리는 30분 동안 조사밀도를 1.5 W/mL로 조절하여 실시하였으며 알칼리와 초음파 전처리를 병합한 동시 전처리를 시행하였다. 그에 따라 SCOD 값이 초기 33.1 mg/L에서 최대 494 mg/L로 증가하였다. 또한 BMP 실험을 실시한 결과 31.2~84.2 mL $CH_4/g$ VS, 9.2~13.5 mL $CO_2/g$ VS로 나타났다. 영양배지와 상등액 슬러지를 주입여부에 따른 BMP 실험을 실시한 결과 각각 73.1, 73.8 mL $CH_4/g$ VS, 11.2, 13.6 mL $CO_2/g$ VS으로 나타났으며 모델값과는 큰 차이를 보이지 않았다. BMP 실험을 종료 후 VS를 분석한 결과 초기 62 %에서 33.8~45.4 %로 감소하였다. 알칼리, 초음파 전처리보다는 동시 전처리가 메탄발생량과 SCOD 값을 증가시켰으며 VS 감소율이 증가하여 혐기성 소화율이 향상되었다.

• 펄프종이기술
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• 제46권1호
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• pp.39-45
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• 2014

Various approaches have been tried to reduce the emission of carbon dioxide in paper industry. One of important approaches is to use PCC manufactured from emission gas as a filler. However, it was recognized that PCC is inferior to other fillers in the paper strength properties of view. Therefore, pretreatment of PCC with pulp powder was tried to mitigate the strength reduction of paper. Pretreatment of PCC with pulp powder improved the bulk(7.4~12.9%) and air permeability(24.8~42.98%), but there is no significant change in opacity. Tensile index, burst index and stiffness were decreased by the use of pretreated PCC with pulp powder. Anionic and cationic PAM were used as a additive for PCC pretreatment in order to improve strength properties. There was no significant change in bulk in all kinds of PAM used in this study. Most strength properties were improved by the pretreatment of PCC with the anionic and cationic PAM and pulp powder, although the opacity and stiffness were more or less decreased.