• Title/Summary/Keyword: SAMs

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Study on barrier characteristics of STM tip/Viologen molecules and morphology (STM tip/Viologen 분자의 Barrier특성과 모폴로지 촉정)

  • Lee, Nam-Suk;Choi, Won-Suk;Qian, Dong-Jin;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2006.10a
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    • pp.91-92
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    • 2006
  • The electrical properties of viologen derivatives were studied in terms of the tunneling current characteristics on the length of the viologen derivatives using self-assembling techniques and ultra high vacuum scanning tunneling microscopy (UHV-STM). We fabricated the Au substrate were deposited by thermal evaporation system ($420^{\circ}C$. Self-assembled monolayers (SAMs) were prepared on Au (111), which had been thermally deposited onto freshly cleaved, heated mica. The Au substrate was exposed to a 1 mM solution of viologen derivatives in ethanol for 24 hours to form a monolayer. We measurement of the morphology on the single viologen molecules ($VC_{8}SH$, $VC_{10}SH$, $HSC_{8}VC_{8}SH$, and $HSC_{10}VC_{10}SH$). The current-voltage (I-V) and differential conductance (dl/dV-V) properties were measured while the electrical properties of the formed monolayer were scanned by using a STS. The effective barrier height of viologen derivatives ($VC_{8}SH$, $VC_{10}SH$, $HSC_{8}VC_{8}SH$, and $HSC_{10}VC_{10}SH$) were calculated to be 1.076 eV, 1.56 ${\pm}$ 0.3 eV, 1.85 eV, 2.28 eV, respectively.

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Plating of Cu layer with the aid of organic film on Si-wafer (유기박막을 이용한 Si기판상의 구리피복층 형성에 관한 연구)

  • Park Ji-hwan;Park So-yeon;Lee Jong-kwon;Song Tae-hwan;Ryoo Kun-kul;Lee Yoon-bae
    • Proceedings of the KAIS Fall Conference
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    • 2004.06a
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    • pp.50-53
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    • 2004
  • 본 논문에서는 Si wafer와 Cu사이의 밀착력을 증가시키기 위해 Si wafer전처리 후 plasma와 SAMs처리 방법에 의한 Cu도금의 형성에 관한 방법을 설명하였다. Si wafer를 Piranha solution과 $0.5\%$ HF처리 후 유기박막인 SAMs과 plasma를 이용하는 방법으로 wafer와 Cu층 사이의 밀착력을 증가시켰다. 도금층의 밀착력은 scratch test 로 측정하였으며, AEM을 이용해 시편에 형성된 패턴의 형태를 관찰하고 SEM과 EDS를 이용해 시편의 조직을 관찰하였다. 그 결과 Si wafer를 O2, He, SAMs를 혼합처리 했을 때 밀착성이 가장 우수하였다.

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Formation of parallel nanostructures by Surface-Patterning Technique for the Application to Nano-Device (나노 소자의 응용을 위한 표면 패터닝 기술을 이용한 평형한 나노구조물 형성)

  • Kim, Yu-Duk;Kim, Hyung-Jin;Hong, Byung-You
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.514-514
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    • 2007
  • 1차원 구조를 갖는 나노 와이어들은 나노 소자를 구현하기 위한 building-block으로 많은 과학자들의 주목을 받고 있고 또한 연구되고 있다. 하지만 그것을 정확하게 위치시키고 일정한 간격으로 정렬시키기 위한 기술 개발은 아직도 해결해야 할 큰 과제로 남아 있다. 이 논문에서, 우리는 ahsing 기술과 표면 패터닝 기술을 이용하여 대면적의 실리콘웨이퍼 위에 DNA(deoxyribonucleic acid)를 기반으로 한 금 나노 와이어를 정확하게 위치시키고 일정한 간격으로 정렬시킬 수 있는 새로운 제어 기술을 제안한다. 먼저 우리는 포토 리소그래피 공정과 $O_2$ 플라즈마 ashing 기술을 이용하여 선폭을 100 nm로 감소 시켰다. 그리고 자기조립단분자막 (self-assembled monolayers; SAMs) 방법과 lift-off 공정을 반복함으로서 1-octadecyltrichlorosilane(OTS) 층과 aminopropylethoxysilane(APS) 층을 형성하였다. 마지막으로 DNA 용액을 샘플 표면 위에 도포하고 분자 빗질 방법으로 DNA를 한 방향으로 정렬 시켰고 금 나노입자 용액을 처리하였다. 그 결과 금 나노 와이어는 $10{\mu}m$ 간격으로 일정하게 정열 되었고, APS 층에만 정확하게 정렬되었다. 우리는 금 나노 와이어를 관찰하기 위하여 원자간력 현미경 (Atomic Force Microscope AFM)을 사용하였다.

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A Study on the Public Acceptance of Offshore Wind Farm near Maldo (말도 인근 해상풍력발전에 대한 주민수용성 연구)

  • Park, Jaepil;Lee, Sanghyuk
    • New & Renewable Energy
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    • v.17 no.3
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    • pp.24-31
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    • 2021
  • Through 'The Renewable Energy 3020 Implementation Plan' for carbon neutrality, the government promised to raise the proportion of renewable energy generation to 20% and renewable energy installation capacity to 63.8% by 2030. Therefore, we plan to test a 5.5 MW offshore wind turbine near Maldo, Gunsan. In this project, we measure the level of public acceptance and perform ordinary least squares (OLS) regression analysis to show the determinants of public acceptance. The regression results are as followed. First, it is judged that the closer the distance to the offshore wind turbine, the more the economic effects considered by residents. Second, especially in Maldo, the experience of being discriminated from the Saemangeum project, is understood to have caused distrust in the surrounding fishing villages chief/Fisheries Cooperatives, converted into a local community effect. Finally, the policy implications are as follows. First, a bottom-up problem-solving method is required to improve public acceptance, based on the Living Lab. Second, the island community may be indifferent to the briefings or forums of outsiders. Therefore, a gradual approach is required through (in)formal channels based on reliability from a long-term perspective with nearby universities and research institutes using SamsØ Energy Academy.

Deposition of Poly(3-hexylthiophene)(P3HT) by Vapor Deposition and Patterning Using Self-Assembled Monolayers (Oxide 표면에 Self-Assembly Monolayers를 이용한 전도성 고분자 Poly(3-hexylthiophene)(P3HT) 증착 및 Patterning 연구)

  • Pang, Il-Sun;Kim, Hyun-Ho;Kim, Sung-Soo;Lee, Jae-Gab
    • Korean Journal of Materials Research
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    • v.18 no.12
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    • pp.664-668
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    • 2008
  • Vapor phase polymerization of a conductive polymer on a $SiO_2$ surface can offer an easy and convenient means to depositing pure and conductive polymer thin films. However, the vapor phase deposition is generally associated with very poor adhesion as well as difficulty when patterning the polymer thin film onto an oxide dielectric substrate. For a significant improvement of the patternability and adhesion of Poly(3-hexylthiophene) (P3HT) thin film to a $SiO_2$ surface, the substrate was pre-patterned with n-octadecyltrichlorosilane (OTS) molecules using a ${\mu}$-contact printing method. The negative patterns were then backfilled with each of three amino-functionalized silane self-assembled monolayers (SAMs) of (3-aminopropyl) trimethoxysilane (APS), N-(2-aminoethyl)-aminopropyltrimethoxysilane (EDA), and (3- trimethoxysilylpropyl)diethylenetriamine (DET). The quality and electrical properties of the patterned P3HT thin films were investigated with optical and atomic force microscopy and a four-point probe. The results exhibited excellent selective deposition and significantly improved adhesion of P3HT films to a $SiO_2$ surface. In addition, the conductivity of polymeric thin films was relatively high (${\sim}13.51\;S/cm$).

Characterizations of Modified Silica Nanoparticles(I)

  • Min, Seong-Kee;Park, Chan-Young;Lee, Won-Ki;Seul, Soo-Duk
    • Korean Journal of Materials Research
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    • v.22 no.6
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    • pp.275-279
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    • 2012
  • (3-mercaptopropyl)trimethoxysilane (MPTMS) was used as a silylation agent, and modified silica nanoparticles were prepared by solution polymerization. 2.0 g of silica nanoparticles, 150 ml of toluene, and 20 ml of MPTMS were put into a 300 ml flask, and these mixtures were dispersed with ultrasonic vibration for 60 min. 0.2 g of hydroquinone as an inhibitor and 1 to 2 drops of 2,6-dimethylpyridine as a catalyst were added into the mixture. The mixture was then stirred with a magnetic stirrer for 8 hrs. at room temperature. After the reaction, the mixture was centrifuged for 1 hr. at 6000rpm. After precipitation, 150 ml of ethanol was added, and ultrasonic vibration was applied for 30 min. After the ultrasonic vibration, centrifugation was carried out again for 1 hr. at 6000rpm. Organo-modification of silica nanoparticles with a ${\gamma}$-methacryloxypropyl functional group was successfully achieved by solution polymerization in the ethanol solution. The characteristics of the ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) were examined using X-ray photoelectron spectroscopy (XPS, THERMO VG SCIENTIFIC, MultiLab 2000), a laser scattering system (LSS, TOPCON Co., GLS-1000), Fourier transform infrared spectroscopy (FTIR, JASCO INTERNATIONL CO., FT/IR-4200), scanning electron microscopy (SEM, HITACHI, S-2400), an elemental analysis (EA, Elementar, Vario macro/micro) and a thermogravimetric analysis (TGA, Perkin Elmer, TGA 7, Pyris 1). From the analysis results, the content of the methacryloxypropyl group was 0.98 mmol/g and the conversion rate of acrylamide monomer was 93%. SEM analysis results showed that the organo-modification of ultra-fine particles effectively prevented their agglomeration and improved their dispensability.

The Research Regarding Cheong-Sam Pattern of Fabric Design in the Period of the Republic of China(1912-1949) - Comparison Between Jing Pai and Hai Pai - (중국 민국시대(1912년-1949년)에 나타난 치파오 문양에 관한 연구 - 경파이 치파오와 해파이 치파오의 문양 비교를 중심으로 -)

  • Seo, A-Jeong;Oh, Hee-Kyoung;Kim, Sook-Jin
    • Journal of the Korea Fashion and Costume Design Association
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    • v.15 no.3
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    • pp.69-83
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    • 2013
  • Clothes show not just the different social status of people, but the ideology and value of former society through pattern, colour, materials, shapes, etc. The purpose of this article is to fill the academic blank of this part by researching the pattern of fabric design in Jing Pai(Beiing style) and Hai Pai(Shanghai style) cheong-sam during the period of the Republic of China. The contrastive analysis of regional pattern between Jing Pai and Hai Pai cheong-sam expect to provide the theoretical basis for the former fashion designers and scholars. There are three approaches in the article: Data collection method, comparison method and Combining theory with practice method as film. Regarding components of pattern, both Jing Pai and Hai Pai cheong-sam have mostly single or composite pattern like plants. Further the most of Jing Pai cheong-sam pattern is traditional flower pattern. But Haipai cheong-sam patterns have some western flower pattern. Beside that, it have some geometry pattern. Regarding arrangement of the pattern, both cheong-sams have scattered dot style, the border style, and pictures style. But continuous type of Jing Pai cheong-sam is less while Hai Pai cheong-sam is the most. Comparing Jing Pai cheong-sam color of patterns in "Moment in Peking" is unadorned and types are simple as chinese traditional clothes; However, "In the Mood for Love" introduces us various material colors, new types of patterns and extraneous characteristic geometry patterns of Hai Pai cheong-sam. Generally speaking, the main characteristic of Jing Pai cheong-sam is traditional and conservatism. It keeps Chinese traditional pattern and culture to the most extent. However, Hai Pai cheong-sam are confluent and open with absorbed external culture and techniques which are endowed new artistic color.

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The Validation of a Measurement for Assessing the Capacity of Korean Older Adults to Consent to Research (한국노인의 연구참여를 위한 동의능력평가척도의 타당성 연구)

  • Lee, Min-Hong
    • Korean Journal of Social Welfare
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    • v.61 no.3
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    • pp.55-76
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    • 2009
  • This study tested the psychometric properties of the Korean version of the Capacity-to-Consent Screen: K-CCS) scale. A total of 404 South Korean older adults were e Cruited using the purposive sampling method. The participants were asked to res-Cod to a structured questiConaire which included older adults' characteristics, ADLs, IADLs, cognitive impairments and creen: K-CCS) scale. A total of. Item analysis, explonalory factor analysis(EFA), and ) sfirmalory factor analysis(CFA) were cCoducted to verifK-Che psychometric properties of the Korean Version of CCS. The sample was divided into two groups: one group for EFA(n=202) alysis(Eois(r group for CFA(n=202). The totults revealeysisae. he final version of the 8-item K-CCS with two dimensions had a excellent internof. Itemstencyonofpha value=.f) alysa CFA) sfirmed the acceptaas diviof the modef.fdi(RMSEA=.057, NNFI=.f4, IFI=.f6, CFI=.f6) to twaddition, claims for the convergent and criterion-related validdiviwere demItetnaled. Ity-tnclusion, the K-CCS can be rmed for professi sams to asersioolder participants' capacity to consent to clinical or survey research.

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Analysis of calcium phosphate nanoclusters using the TOF-MEIS

  • Jung, Kang-Won;Park, Jimin;Yang, Ki Dong;Nam, Ki Tae;Moon, DaeWon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.228.2-228.2
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    • 2015
  • We have developed a TOF-MEIS system using 70~100 keV He+. A TOF-MEIS system was designed and constructed to minimize the ion beam damage effect by utilizing a pulsed ion beam with a pulse width < 1 ns and a TOF delay-line-detector with an 120 mm diameter and a time resolution of 180 ps. The TOF-MEIS is an useful tool for interfacial analysis of the composition and structure of nano and bio systems. Our recent applications are reported. We investigated the effect with Polyaspartic Acid (pAsp) and Osteocalcin on the initial bone growth of calcium hydroxyl appatite on a carboxyl terminated surface. When pAsp is not added to the self-assembled monolayers of Ca 2mM with Phosphate 1.2 mM, the growth procedure of calcium hydroxyl appatite cannot be monitored due to its rapid growth. When pAsp is added to the SAMs, the initial grow stage of the Ca-P can be monitored so that the chemical composition and their nucleus size can be analyzed. Firstly discovered the existence of 1-nm-sized abnormal calcium-rich clusters (Ca/P ~ 3) comprised of three calcium ions and one phosphate ion. First-principles studies demonstrated that the clusters can be stabilized through the passivation of the non-collagenous-protein mimicking carboxyl-ligands, and it progressively changes their compositional ratio toward that of a bulk phase (Ca/P~1.67) with a concurrent increase in their size to ~2 nm. Moreover, we found that the stoichiometry of the clusters and their growth behavior can be directed by the surrounding proteins, such as osteocalcin.

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Process Development of Self-Assembled Monolayers(SAMs) of Colloidal Particles (콜로이드 입자의 자기 배열성을 이용한 Monolayer 형성에 관한 연구)

  • Ko, Hwa-Young;Lee, Hae-Weon;Kim, Joo-Sun;Moon, Joo-Ho
    • Journal of the Korean Ceramic Society
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    • v.39 no.10
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    • pp.981-987
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    • 2002
  • Monodispersed colloidal silica was prepared by Stober process. We have synthesized monodispersed colloidal silica of carious sizes (100 nm, 200 nm, 300 nm) by controlling volume ratios of TEOS(Tetraethylorthosilicate), $NH_4OH$, Ethanol and D. I. water. Shape and monodispersity of the synthesized colloidal particles were observed by Scanning Electron Microscopy(SEM) and laser light scattering particle analyzer. Self-assembled monolayer of monodispersed colloids was achieved by dipping Si substrate into a well-dispersed silica suspension. It was determined that uniformity and spatial extent of the self-assemble monolayer of monodispersed colloids are significantly influenced by the experimental parameters such as concentration, pH and surface tension of the colloidal suspension. We have observed a hexagonally well-ordered packing colloidal monolayer in a relatively large area (1.5 mm ${\times}$ 1.5 mm) as confirmed by SEM.