• 한국콘텐츠학회논문지
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• 제12권7호
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• pp.273-283
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• 2012

급성심근경색증 환자에서 약물 용출 스텐트(drug-eluting stents, DES)는 일반 금속 스텐트(bare-metal stents, BMS)에 비해 재협착은 감소하지만 구조적인 특성으로 스텐트 혈전증(stent thrombosis, ST)이 증가한다고 알려져 있다. 이에 본 연구에서는 ST의 발생빈도, 임상양상, 그리고 1년간 예후를 알아보고자 하였다. 대학병원 심혈관센터에서 급성심근경색증으로 관상동맥 중재술을 받은 2,667명에서 스텐트 혈전증이 발생한 환자 80명을 대상으로 DES-ST를 I군(n=57), BMS-ST(n=23)를 II군으로 분류하여 양군 간의 특징을 분석하였다. 양군간의 ST는 I군에서 57명(2.7%)과 II군에서 23명(4.3%)로 양군 간에 유의한 차이는 없었다(p>0.064). ST의 유형으로는 acute ST는 I군5(8.8%), II군3(2.3%), subacute ST는 I군 29(50.9%), II군14(60.9%), late ST 는 I군11(19.3%), II군2(8.7%), very late ST는 I군12(21.1%), II군 4(17.4%)로 양군간의 차이는 없었다(p>0.605). DES와 BMS를 삽입 후 1년 예후에 미치는 인자로는 ST(OR 8.166 95% CI 2.825-23.608 p<0.001), 좌심실구혈율(<40) (OR 6.409 95% CI 2.422-16.955 p<0.001), 나이(${\geq}$75세) (OR 4.979 95% CI 1.946-12.744 p=0.001) 이었다. ST의 발생율은 양군 사이에 차이가 없었고, 1년 예후에 미치는 인자로는 ST의 발생, 좌심실 구혈률의 저하 및 환자의 연령 등 이었다.

• 대한기계학회논문집
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• 제12권4호
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• pp.747-754
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• 1988

본 연구에서는 우리나라 자동차업계에서 널리 사용되는 복합조직인 고장력 강 판(high strength steel sheet, HS)과 아연도금강판(galvanized steel sheet, GA)을 선택하여 각 강판간의 점용접 피로특성을 규명하기 위하여 아래와 같은 4가지 조건하 의 단점 점용접 시험편을 제작하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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• pp.57-60
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• 2001

The characterization of organic Metal/Insulator/Metal(MIM) devices were investigated from LB films. The physicochemical properties of the LB films were by UV absorption spectrum and AFM. We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 2, 10, 30[mN/ml The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it.

• 한국정밀공학회지
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• 제23권12호
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• pp.122-127
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• 2006

This paper reports on the development of carbon nanotube tip modified with focused ion beam(FIB). We used an electric field which causes dielectrophoresis, to align and deposit CNTs on a metal-coated canning Probe Microscope (SPM) tip. Using the CNT attached SPM tip, we have obtained an enhanced resolution and wear property compared to that from the bare silicon tip through the scanning of the surface of the bio materials. The carbon nanotube tip was aligned toward the source of the ion beam allowing their orientation to be changed at precise angles. By this technique, metal coated carbon nanotube tips that are several micrometer in length are prepared for SPM.

• Biomaterials and Biomechanics in Bioengineering
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• 제1권3호
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• pp.131-150
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• 2014

Vascular stenting has a great attention as a treatment for coronary arteries diseases as compared with percutaneous balloon angioplasty. In-stent restenosis and thrombosis are side effects resulting from using bare metal stent (BMS). Employing platelet therapy allowed to reduce the rate of thrombosis, however, the rate of restenosis remains a major problem. In 2002, drug-eluting stents (DESs) were introduced as an effort to reduce the restenosis. The commercially available DESs continue to suffer from coating defects that might lead to a series of adverse effects. Most importantly, multiple concerns remain regarding the polymer coating integrity on metal surfaces or the relation of polymer irregularities to longterm adverse events.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.461-462
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• 2006

This paper reports on the development of a scanning probe microscopy(SPM) tip with caborn nanotubes. We used an electric field which causes dielectrophoresis(DEP), to align and deposit CNTs on a metal-coated SPM tip. Using the CNT attached SPM tip, we have obtained an enhanced resolution and wear property compared to that from the bare silicon tip through the scanning of the surface of the bio materials. The carbon nanotube tip align toward the source of the ion beam allowing their orientation to be changed at precise angles. By this technique, metal coated carbon nanotube tips that are several micrometer in length are prepared for scanning probe microscopy.

• Corrosion Science and Technology
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• 제14권5호
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• pp.218-225
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• 2015

The electrochemical behaviors of various metals with and without diamond-like-carbon (DLC) coating in 3.5 wt% NaCl solution were investigated. The effect of hydrodynamic conditions was focused by employing a rotating disc electrode (RDE). The experimental results showed that each bare metal had a more positive corrosion potential and a higher corrosion rate due to enhanced oxygen transport at the higher rotating speed of the RDE. DLC coating caused a substantial increase in the corrosion resistance of all metals studied. However, localized corrosion was still found in the DLC-coated metal at sites where deposition defects existed. Surface morphology examination was performed after the electrochemical test to confirm the roles of hydrodynamic conditions and DLC coating.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1708-1710
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• 2000

The synthesis and characterization of polymers for organic Metal/Insulator/Metal(MIM) devices were investigated from LB films. The physicochemical properties of the LB films were examined by UV absorption spectrum and AFM. The AFM images showed for network structure of polyurethane monolayer that the film formed an unsymmetry mesh with intermolecular interaction within the large scale. The stable images are probably due to a strong interaction between the monolayer film and Si substrate. We are unable to obtain molecular resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1763-1768
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• 2006

The application of poly(Co(II)-(1,8-diaminonaphthalene))(poly(Co-DAN)) and poly(1,8-diaminonaphthalene) (Poly(1,8-DAN)) to the electrocatalytic reduction of molecular oxygen was investigated, which were electrochemically grown by the potential cycling method on the glassy carbon electrodes. The reduction of oxygen at the polymer and its metal complex polymer coated electrodes were irreversible and diffusion controlled. The Poly(1,8-DAN) and Poly(Co-DAN) films revealed the potential shifts for the oxygen reduction to 30 mV and 110 mV, respectively, in an aqueous solution, compared with that of the bare electrode. Hydrodynamic voltammetry with a rotating ring-disk electrode showed that Poly(1,8-DAN) and Poly(Co-DAN) coated electrodes converted respectively 84% and 22% of $O_2$ to $H_2O$ via a four electron reduction pathway.

• Bulletin of the Korean Chemical Society
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• 제16권3호
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• pp.205-210
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• 1995

Catalytic effects of various Schiff base metal(II) complexes on the reduction of thionyl chloride at glassy carbon electrode are evaluated by determining the kinetic parameters from cyclic voltammetry technique. The charge transfer process is affected strongly by the concentration of catalysts during the reduction of thionyl chloride. The catalytic effects are shown by both a shift of the reduction potential for thionyl chloride toward more positive direction and an increase in peak current. The diffusion coefficient value, Do, of the 8.17 ${\times}$ 10-9 $cm^2/s$ was observed at the bare glassy carbon electrode, whereas larger values (0.9-1.09 ${\times}$ 10-8 $cm^2/s$) were observed at the catalyst supported glassy carbon electrode. Significant improvements in the cell performance have been noted in terms of both exchange rate constants and current densities at glassy carbon electrode.