• 제목/요약/키워드: Fourier transform IR

검색결과 557건 처리시간 0.031초

Preparation and Characterization of Surfactant-Exfoliated Graphene

  • Song, Yeari;Lee, Hoik;Ko, Jaehyoung;Ryu, Jungju;Kim, Minkyoung;Sohn, Daewon
    • Bulletin of the Korean Chemical Society
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    • 제35권7호
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    • pp.2009-2012
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    • 2014
  • An anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), was introduced during the ultrasonication process for exfoliation of graphene. The surfactant plays the roles of exfoliator and stabilizer by binding to the graphene surface. The obtained modified graphene was characterized by Fourier-transform infrared spectroscopy (FT-IR) and solid state $^{13}C$ CP/MAS NMR to analyze the binding between molecules, and by X-ray diffraction (XRD) to characterize the bulk structure. The resulting graphene exhibited good dispersion stability in both water and organic solvents.

Photoluminescence of Porous Silicon Carbide in Solvents

  • Lee, Ki-Hwan;Lee, Tae-Ho;Yoon, Seok-Won;Lee, Seung-Koo;Jeon, Hae-Kwon;Choi, Chang-Shik
    • Journal of Photoscience
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    • 제12권3호
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    • pp.171-174
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    • 2005
  • The relationship between porous surfaces and photoluminescence (PL) behavior of porous silicon carbide (PSC) in various solvents has been studied. The porous surfaces of p-type silicon carbide can be fabricated by electrochemical anodization from the 6H, 15R, 4H-${\alpha}$-SiC substrates in dark-current mode (DCM) condition. We have been investigated the dependence of the PL spectra of PSC under the medium having the different dielectric constants. It has been found that PL depends sensitively on the environment surrounding the surface. The extent of chemically stability on the surface of PSC due to the various solvents was confirmed by reflectance Fourier transform infrared (FTIR) spectroscopy. Detailed IR experiments on the PSC samples were carried out before and after various solvents immersion. These results will be offered important information on the origin of PL in porous structure.

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Preparation and Catalytic Properties of Pt/CNT/TiO2 Composite

  • Chen, Ming-Liang;Zhang, Feng-Jun;Oh, Won-Chun
    • 한국세라믹학회지
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    • 제47권4호
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    • pp.269-275
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    • 2010
  • In this study, we successfully prepared CNT/$TiO_2$, Pt/CNT and Pt/CNT/$TiO_2$ composites and investigated their photocatalytic activity in MB solution by irradiation under UV light. Fourier transform infrared (FT-IR) spectroscopy was used to characterize the functional group on the surface of MWCNTs, which oxidized by MCPBA. Brunauer-Emmett-Teller (BET) surface area, transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) were used to analyze the prepared composites. The results of the decomposition of the MB solution indicated that the Pt/CNT/$TiO_2$ composite had the best photocatalytic activity among the three kinds of composites.

펄스 레이저 증착법에 의한 DLC 박막 제작 연구 (Study on the fabrication of DLC thin films by pulsed laser deposition)

  • 정영식;은동석;이상렬;정해석;박형호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.285-287
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    • 1997
  • We have deposited hydrogen-free diamond-like carbon (DLC) films by pulsed laser deposition of graphite. Pulsed laser deposition (PLD) can be utilized to generate films with desired properties quite different from those of the starting material. Since DLC films grown by PLD using turbo pump are perpared without hydrogen, they have a higher density and a higher index of refraction than the hydrogenated DLC films. In this study, effects of the substrate temperature and laser energy density on the properties of DLC films were systematically investigated. The structure and properties of the films have been studied by scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), and Raman spectroscopy.

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Methacryloxypropyltrimethoxysilane(MAPTMS)의 광그라프트에 의한 PET직물의 열적 안정성 향상 (Improved Thermal Stability of PET Fabrics by Photografting of Methacryloxypropyltrimethoxysilane(MAPTMS))

  • 장진호;손정아
    • 한국염색가공학회지
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    • 제20권4호
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    • pp.1-7
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    • 2008
  • Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

에틸 아세토아세테이트 토토머리즘 평형 상수의 밀도 의존성 (The Effect of Solvent Density on the Ethyl Acetoaceate Tautomerism)

  • 박윤국
    • 공업화학
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    • 제17권3호
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    • pp.291-295
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    • 2006
  • 본 연구에서는 아임계 및 초임계 이산화탄소하의 에틸 아세토아세테이트의 케토-에놀 토토머릭 평형상수를 후리에 적외선 분광기를 이용하여 세 가지 다른 온도에서 측정하였다. 케토-에놀 토토머릭 평형상수의 용매에 대한 밀도 의존성을 연구하기 위하여 정온하에서 이산화탄소의 압력을 변화시켰다. 용매인 이산화탄소의 밀도를 증가 시키면, 케토 토토머의 양이 증가하게 되어 케토-에놀 토토머릭 평형상수값이 감소한다. 에틸 아세토아세테이트의 케토-에놀 토토머릭 평형상수의 밀도의존성을 연구하기 위하여 변형된 격자유체수소결합 모델을 적용하였다.

Field Emission Characteristics of Nitrogen-Doped and Micro-Patterned Diamond-Like Carbon Films Prepared by Pulsed Laser Deposition

  • Shin, Ik-Ho;Lee, Taek-Dong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.133-134
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    • 2000
  • Effect of nitrogen doping on field emission characteristics of patterned Diamond-like Carbon (DLC) films was studied. The patterned DLC films were fabricated by the method reported previously[1]. Nitrogen doping in DLC film was carried out by introducing $N_2$ gas into the vacuum chamber during deposition. Higher emission current density of $0.3{\sim}0.4$ $mA/cm^2$ was observed for the films with 6 at % N than the undoped films but the emission current density decreased with further increase of N contents. Some changes in CN bonding characteristics with increasing N contents were observed. The CN bonding characteristics which seem to affect the electron emission properties of these films were studied by Raman spectroscopy, x-ray photoemission spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The electrical resistivity and the optical band gap measurements showed consistence with the above analyses.

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Effect of Preparation on Structure and Magnetic Properties of ZnFe2O4

  • Niyaifar, Mohammad
    • Journal of Magnetics
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    • 제19권2호
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    • pp.101-105
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    • 2014
  • In this work, Zinc ferrite nanoparticles have been prepared by various methods, conventional (ZC), mechanochemical processing (ZM) and Sol-Gel (ZS) method, to compare their structural and magnetic properties. The cation distribution obtained from XRD shows the degrees of inversions are 4%, 14.8%, and 16.4% from the normal $ZnFe_2O_4$ structure. Fourier transform infrared spectroscopy (FT-IR) confirms changes in cation distribution of $ZnFe_2O_4$ fabricated by sol-gel and mechanochemical processing. The $^{57}Fe$ M$\ddot{o}$ssbauer spectra of the samples were recorded at room temperature. The spectra exhibit a line broadening. The magnetic properties of the samples were studied by vibration sample magnetometer (VSM) at room temperature and the results show that the sample ZM has ferrimagnetic behaviour.

The Effect of Salt and pH on the Phase Transition Behaviors of pH and Temperature-Responsive Poly(N,N-diethylacrylamide-co-methylacrylic acid)

  • Liu, Tonghuan;Fang, Jian;Zhang, Yaping;Zeng, Zhengzhi
    • Macromolecular Research
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    • 제16권8호
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    • pp.670-675
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    • 2008
  • A series of pH and temperature-responsive (N,N-diethylacrylamide-co-methylacrylic acid) copolymers were synthesized by radical copolymerization and characterized by elemental analysis, Fourier-transform infrared (FT-IR), nuclear magnetic resonance (NMR) $^1H$, $^{13}C$ and LLS. The effects of salt and pH on the phase transition behaviors of the copolymers were investigated by uv. With increasing NaCl concentration, significant salt effects on their phase transition behaviors were observed. UV spectroscopic studies showed that the phase transition became faster with increasing NaCl concentration. In addition, the phase transition behaviors of copolymers were sensitive to pH. The pH and temperature sensitivity of these copolymers would make an interesting drug delivery system.

표면 개질된 메조기공실리카를 이용한 수중의 인 제거 (Surface modified mesoporous silica (SBA-15) for phosphate adsorbents in water)

  • 이승연;최재우;이상협;이해군;이기봉;홍석원
    • 상하수도학회지
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    • 제25권5호
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    • pp.719-724
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    • 2011
  • The excessive phosphate in water causes eutrophication which destroys water environment. In this study, mesoporous silica was synthesized and several functional groups were attached on it. Samples were tested to identify the ability to remove phosphate. The structures of synthesized materials were analyzed by X-ray diffractions (XRD), Fourier transform-infrared (FT-IR) and surface area analysis, Brunauer-Emmett-Teller (BET). To determine the maximum phosphate adsorption capacities and sorption rate, the equilibrium test and kinetic test was conducted. Among functionalized SBA-15 samples, pure SBA-15 didn't adsorb phosphate but Al-SBA-15 and Ti-SBA-15 showed good performances to remove phosphate. The maximum phosphate adsorption capacity of Al-SBA-15 was efficient compared to other adsorbents.