• 한국포장학회지
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• 제20권2호
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• pp.41-49
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• 2014

This study illustrates the synthesis of gelatin based zinc oxide nanoparticle (ZnONPs) incorporated nanocomposite films using different concentrations of ZnONPs. The ZnONPs were oval in shape and the size ranged from 100- 200 nm. The nanocomposite films were characterized by UV-visible, FE-SEM, FT-IR, and XRD. The concentrations of ZnONPs greatly influenced the properties of nanocomposite films. The absorption peaks around 360 nm increased with the increasing concentrations of ZnONPs. The surface color of film did not change while transmittance at 280 nm was greatly reduced with increase in the concentration of ZnONPs. FTIR spectra showed the interaction of ZnONPs with gelatin. XRD data demonstrated the crystalline nature of ZnONPs. The thermostability, char content, water contact angle, water vapor permeability, moisture content, and elongation at break of nanocomposite films increased, whereas, tensile strength and modulus decreased with increase in the concentrations of ZnONPs. The gelatin/ZnONPs nanocomposite films showed profound antibacterial activity against both Gram-positive and Gram-negative food-borne pathogenic bacteria. The gelatin/$ZnONP^{1.5}$ nanocomposite film showed the best UV barrier and antimicrobial properties among the tested-films, which indicated a high potential for use as an active food packaging films with environmentally-friendly nature.

• Current Photovoltaic Research
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• 제3권3호
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• pp.71-74
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• 2015

Soluble polyaniline was synthesized by attaching titanium isoproxide ($Ti(OPr)_4$) to the amine group of the aniline. Approximately 1 to 1 molar ratio of aniline and $Ti(OPr)_4$ was mixed and polymerized with ammonium persulfate. The FTIR result showed clear difference between $TiO_2$-aniline composite ($TiO_2An$) and $TiO_2$-polyaniline composite ($TiO_2PAn$). Although the $TiO_2An$ had negligible UV-visible absorption, the $TiO_2PAn$ showed strong absorption in the UV-visible region. Photoluminescence (PL) peaks of $TiO_2An$ were shifted toward red with the reduction of the excitation energy, which could be due to the multiple emission centers. The luminescence peak shift stopped at 501 nm. The PL spectra of $TiO_2PAn$ exhibited three emission peaks at 2.88 eV (430 nm), 2.48 eV (501 nm) and 2.22 eV (558 nm). The new emission center (2.22 eV) was observed after polymerization. Field emission scanning electron microscope image showed crack-free composite film.

• 전기화학회지
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• 제2권1호
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• pp.38-45
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• 1999

Electrochemical lithium intercalation into a PECVD (plasma enhanced chemical vapour deposited) carbon film electrode was investigated in 1 M $LiPF_6-EC$ (ethylene carbonate) and DEC (diethyl carbonate) solution during lithium intercalation and deintercalation, by using cyclic voltammetry supplemented with ac-impedance spectroscopy. The size of the graphitic crystallite in the a- and c-axis directions obtained from the carbon film electrode was much smaller than those of the graphite one, indicating less-developed crystalline structure with hydrogen bonded to carbon, from the results of AES (Auger electron spectroscopy), powder XRD (X-ray diffraction) method, and FTIR(Fourier transform infra-red) spectroscopy. It was shown from the cyclic voltammograms and ac-impedance spectra of carbon film electrode that a threshold overpotential was needed to overcome an activation barrier to entrance of lithium into the carbon film electrode, such as the poor crystalline structure of the carbon film electrode showing disordered carbon and the presence of residual hydrogen in its structure. The experimental results were discussed in terms of the effect of host carbon structure on the lithium intercalation capability.

• 대한화학회지
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• 제34권6호
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• pp.534-538
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• 1990

H$_2$O을 용매로 하여 헤테로고리 염기인 이소퀴놀린과 CrO$_3$를 반응시켜 Cr(Ⅵ)화합물인 [$C_9H_7$NH]$_2Cr_2O_7$을 얻었다. 이 화합물은 비흡수성이면서 물에 잘 녹았다. 그리고 원소분석, 적외선 분광법으로 이 화합물의 구조가 [$C_9H_7$NH]$_2Cr_2O_7$임을 확인하였다. 또한, 이 화합물이 여러 가지 알코올을 알데히드나 케톤으로 전환시킬 수 있는 산화제로 작용하는가를 알아보기 위하여 알릴, 일차, 이차 알코올을 각각 산화반응에 이용한 결과 알코올들에 대해 효율적인 산화제로 작용하였다.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.927-933
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• 2011

Conducting polyaniline-poly($\varepsilon$-caprolactone) polymer composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of poly($\varepsilon$-caprolactone) (PCL) (10%, 20%, 30%, 40%, and 50%), the oxidative polymerization of aniline was achieved using ammonium persulfate as an oxidant. FTIR, UV-vis spectra, and X-ray diffraction studies support a strong interaction between polyaniline (PANI) and PCL. Structural morphology of the PANI-PCL polymer composites was studied using scanned electron microscopy (SEM) and transmittance electron microscopy (TEM), and thermal stability was analyzed by thermogravimetric analysis (TGA) technique. The temperature-dependent DC conductivity of PANI-PCL polymer composite films was studied in the range of 305-475 K, which revealed a semiconducting behavior in the transport properties of the polymer films. Conductivity increased with the increase of PCL in below critical level, however conductivity of the polymer film was decreased with increase of PCL concentration higher than the critical value.

• 한국결정성장학회지
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• 제3권1호
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• pp.31-36
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• 1993

FZ법을 이용하여 Tourmaline ($NaFe_3Al_6B_3Si_6O_{27}F_4$) 단결정을 성장하였다. 성장조건으로 회전수 상호 역방향으로 20~30rpm, 성장속도 2~5mm/hr로 조절하였다. 성분 원소 중 전이금속 원소가 존재하여 dopant는 첨가하지 않았다. 원료봉은 $1000~1100^{\circ}C$에서 소결하였고 이 온도보다 고온의 영역에서는 F등의 휘발원소의 휘발로 인해 원료봉을 제작하기가 어려웠다. 성장된 결정은 어두운 색을 띄고 있었고 길이 60~50mm, 직경 5~6mm였다. 결정의 원료에 대하여 XRD 분석을 통하여 Tourmaline 조성을 확인하였고 FTIR로 성분의 결합상을 보았다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.8-8
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• 2008

Two-dimensional photonic quasicrystal (PQCs) template patterns have been fabricated on a $1.1{\mu}m$-thick DMI-150 photoresist using a multiple-exposure holographic method. A 442-nm HeCd laser was utilized as a light source and the holographic exposure was carried out at a fixed angle of $\theta=6^{\circ}$. After the first holographic exposure, the sample was rotated to a proper angle and the second exposure was performed to the same manner. This exposure process was repeated n/2 times to obtain n-fold symmetric PQC patterns and then the sample was developed. The fabricated PQCs exhibited 8, 10 and 12-fold rotational symmetry and the diffraction patterns using a 632.8-nm HeNe laser were observed for n-rotation symmetry corresponding n-fold PQCs. The fabricated PQC template patterns were examined using scanning electron microscopy(SEM). Transmission spectra were measured fourier transform infrared(FTIR) spectrometer.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.2031-2036
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• 2012

Melt copolymerization reactions of several bis(diethylamino)silane derivatives, bis(diethylamino)methylphenylsilane, bis(diethylamino)methyloctylsilane, 1,2-bis(diethylamino)tetramethyldisilane, and 1,3-bis(diethylamino) tetramethyldisiloxane, with 2,7-dihydroxyfluoren-9-one were carried out to yield poly[oxy(2,7-fluoren- 9-onenylene)oxy(diorganosilylene)]s bearing the fluoren-9-one fluorescent aromatic group in the polymer main chain: poly[oxy(2,7-fluoren-9-onenylene)oxy(methylphenylsilylene)], poly[oxy(2,7-fluoren-9-onenylene) oxy(methyloctylsilylene)], poly[oxy(2,7-fluoren-9-onenylene)oxy(tetramethyldisilylene)], and poly[oxy- (2,7-fluoren-9-onenylene)oxy(tetramethyldisiloxanylene)]. These polymeric materials are soluble in common organic solvents such as $CHCl_3$ and THF. FTIR spectra of all the materials reveal characteristic Si-O-C stretching frequencies at 1012-1018 $cm^{-1}$. In the THF solution, the prepared materials show strong maximum absorption peaks at 258-270 nm, strong maximum excitation peaks at 260-280 nm, and strong maximum fluorescence emission bands at 310-420 nm. TGA thermograms suggest that most of the polymers are essentially stable to $200^{\circ}C$ without any weight loss and up to $300^{\circ}C$ with only a weight loss of less than 5% in nitrogen.

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.44-52
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• 2006

New organotin(IV) derivatives with general formulae R_2SnL_2 and R_3SnL, where R = methyl, n-butyl, n-octyl and phenyl and HL is either 3-[N-(4-nitrophenyl)amido]-propenoic acid or 3-[N-(4-nitrophenyl)amido] propanoic acid have been synthesized in 1 : 2 and 1 : 1 molar ratio by different methods. The FTIR spectra clearly demonstrated that the organotin(IV) moieties react with [O,O] atoms of the ligands. The bonding and coordination behavior in these complexes are discussed on the basis of multinuclear (^1H,\,^{13}C,\,^{119}Sn) NMR and mass spectrometric studies. Antibacterial, and antifungal screening tests were performed for these compounds and reported here. These values were compared to those of the precursors and it was found that diorganotin(IV) complexes exhibit less activity as compared to triorganotin(IV) complexes . LD_{50} data were obtained by Brine Shrimp assay method. Insecticidal activity was performed for selective compounds by contact toxicity method.

• 한국진공학회지
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• 제21권4호
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• pp.212-218
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• 2012

RF 마그네트론 스퍼터에 의해 만들어진 AZO 박막을 기판의 화학적 특성에 따른 광학적 특성에 대하여 조사하였다. 기판은ICP-CVD방법으로 제작된 SiOC 박막으로 화학적 특성의 변화를 관찰하기 위해서 산소와 아르곤(DMDMOS)가스의 유량비를 다르게 하여 증착하였다. 아르곤의 유량이 증가할수록 Si-O 결합이 증가하였으며, 비정질구조가 증가되었다. 비정질도가 높은 SiOC 박막 위에 성장된 AZO 박막의 거칠기는 감소하였으며, 표면의 평탄도가 개선되었다. 더불어 비정질도가 높은 SiOC박막 위에 성장된 AZO 박막에서 자외선 영역의 방사 강도가 제일 높았다.