• 분석과학
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• 제5권1호
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• pp.97-101
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• 1992

순수한 니켈과 티타늄이 같은 양 함유되어 있는 NiTi 금속간 화합물의 인공 생리식염수에서의 부식 특성을 순수한 니켈 및 티타늄과 함께 연구하였다. Tafel 외삽법과 선형 분극법 공히 유사한 결과를 보였으며, 부식 전류 Icorr와 부식 속도는 다음과 같은 순서로 증가하였다. NiTi

• 한국세라믹학회지
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• 제49권2호
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• pp.135-141
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• 2012

To improve the visible-light induced photocatalytic application performances of $TiO_2$, in this study, the $NiS_2$ modied $TiO_2$ composites were prepared by two methods: hydrothermal method and sol-gel method. The composites were denoted as hs-$NiS_2$/$TiO_2$, and sg-$NiS_2$/$TiO_2$ and characterized by XRD, UV-vis absorbance spectra, SEM, TEM, EDX, and BET analysis. The photocatalytic activities under visible light were investigated by the degradation of methyl orange (MO). The photodegradation rate of methyl orange under visible light with $NiS_2$/$TiO_2$ composites was markedly higher than that of pure $TiO_2$, and the effect of hs-$NiS_2$/$TiO_2$ composites was better than that of sg-$NiS_2$/$TiO_2$. The results indicate that the hydrothermal process could partly inhibit the agglomeration of $NiS_2$/$TiO_2$. Thus, the dispersion of nanoparticles was improved, and that the promoting effect of $NiS_2$ could extend the light absorption spectrum toward the visible region.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1371-1374
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• 2001

Metal doping was adopted to modify TiO2 (P-25) and enhance the photocatalytic degradation of harmful cyanides in aqueous solution. Ni, Cu, Co, and Ag doped TiO2 were found to be active photocatalysts for UV light induced degradation of aqueous cyanides generating cyanate, nitrate and ammonia as main nitrogen-containing products. The photoactivity of Ni doped TiO2 was greatly affected by the state of Ni, that is, the crystal size and the degree of reduction of Ni. The modification effects of some mixed oxides, that is, Ni-Cu/TiO2 were also studied. The activity of Ni-Cu/TiO2 for any ratio of Cu/Ni was higher than that of Ni- or Cu-doped TiO2, and the catalyst at the Cu/Ni ratio of 0.3 showed the highest activity for cyanide conversion.

• 한국세라믹학회지
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• 제48권3호
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• pp.211-216
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• 2011

Nickel oxide-doped ACF and $TiO_2$ composites (NiO/ACF/$TiO_2$) were prepared by a sol-gel method. The composite obtained was characterized by BET surface area measurements, X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis. A methylene blue (MB) solution under visible light irradiation was used to determine their photocatalytic activity. Excellent photocatalytic degradation of the MB solution was observed using the $TiO_2$, Ti-ACF and NiO/ACF/$TiO_2$ composite under visible light.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4052-4058
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• 2012

The composite photocatalyst, N-$TiO_2$ loaded with $Ni_2O_3$, was prepared by $N_2$ plasma treatment. X-ray diffraction, X-ray fluorescence, $N_2$ adsorption, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared $TiO_2$ samples. The results indicated that the band gap energy was decreased obviously by nitrogen doping, whereas loading of $Ni_2O_3$ did not influence the band gap and visible light absorption. The photocatalytic activities were tested in the degradation of 2,4,6-trichlorophenol (TCP) under visible light. The photocatalytic activity and stability of composite photocatalyst were much higher than that of catalyst modified with nitrogen or $Ni_2O_3$ alone. The synergistic effect of doping nitrogen and $Ni_2O_3$ over $TiO_2$ was investigated.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.486-496
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• 2018

Bimetallic Pd@Ni nanostructure exhibited enhanced co-catalytic activity for the selective hydrogenation of benzaldehyde compare to their monometallic counterparts. Impregnation of these mono/bimetallic nanostructures on mesoporous $TiO_2$ leads to several surface modifications. The bimetallic PNT-3 ($Pd_3@Ni_1/mTiO_2$) exhibited large surface area ($212m^2g^{-1}$), and low recombination rate of the charge carriers ($e^--h^+$). The hydrogenation reaction was analyzed under controlled experiments. It was observed that under UV-light irradiations and saturated hydrogen atmosphere the bimetallic PNT-3 photocatalyst display higher rate constant $k=5.31{\times}10^{-1}h^{-1}$ owing to reduction in the barrier height which leads to efficiently transfer of electron at bimetallic/$mTiO_2$ interface.

• 대한소아치과학회지
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• 제49권4호
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• pp.505-513
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• 2022

고탄성의 가는 강선을 이용한 부분교정은 약한 힘의 적용으로 고정원에 대한 부담을 줄이면서 치료기간을 단축시킬 수 있다. 기공실 과정 없이 즉시 적용이 가능하고 환자의 협조를 필요로 하지 않기 때문에 임상적으로 유용하게 사용될 수 있다. 본 증례들은 직선형의 0.012 인치 NiTi 분절 강선과 유동성 레진만을 이용하여 전치, 소구치, 대구치 등 구강 내 다양한 위치에 존재하는 문제들에 적용하여 단기간에 양호한 결과를 얻었기에 보고하는 바이다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.667-672
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• 2005

In order to effectively utilize visible light in the photocatalytic reaction, nanaocomposite of Ni doped $TiO_2$ and $NiTiO_3$ powders were synthesized by mechanical alloying and heat treatment. About 5.4 wt% of $NiTiO_3$ with particle size less than 15nm was uniformly formed in the Ni-doped rutile $TiO_2$ matrix. The UV/VIS-DRS and PL investigation showed that the nanocompasite $TiO_2$ powders had a longer absorpt ion wavelength (600$\sim$650nm, 2.0$\sim$1.9eV) than that of Ni-doped $TiO_2$ or rutile $TiO_2$ powder. The carbon decomposition of 4-CP by the nanocompasite $TiO_2$ powders were higher than other $TiO_2$ (P-25).

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.350-355
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• 2009

The crysralline silicon solar cell where the solar cell market grows rapidly is occupying of about 85% or more high efficiency and low cost endeavors many crystalline solar cells. The fabricaion process of high efficiency crystalline silicon solar cells necessitate complicated fabrication processes and Ti/Pd/AG contact, This metal contacts have only been used in limited areas in spite of their good srability and low contact resistance because of expensive materials and process. Commercial solar cells with screen-printed solar cells formed by using Ag paste suffer from loe fill factor and high contact resistance and low aspect ratio. Ni and Cu metal contacts have been formed by using electroless plating and light-induced electro plating techniques to replace the Ti/Pd/Ag and screen-printed Ag contacts. Copper and Silver can be plated by electro & light-induced plating method. Light-induced plating makes use the photovoltaic effect of solar cell to deposit the metal on the front contact. The cell is immersed into the electrolytic plating bath and irradiated at the front side by light source, which leads to a current density in the front side grid. Electroless plated Ni/ Electro&light-induced plated Cu/ Light-induced plated Ag contact solar cells result in an energy conversion efficiency of 16.446 % on 0.2~0.6${\Omega}$ cm, $20{\times}20mm^2$, CZ(Czochralski) wafer.

• 한국재료학회지
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• 제14권9호
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• pp.634-641
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• 2004

The photocatalytic performance of $TiO_2$ thin films coated on porous alumina balls using various aqueous $TiOCl_2$ solutions as starting precursors, to which 1.0 $mol\%$ transition metal ($Ni^{2+},\;Cr^{3+},\;Fe^{3+},\;Nb^{3+},\;and\;V^{5+}$) chlorides had been already added, has been investigated, together with characterizations for $TiO_2$ sols synthesized simultaneously in the same autoclave through hydrothermal method. The synthesized $TiO_2$ sols were all formed with an anatase phase, and their particle size was between several nm and 30 nm showing ${\zeta}-potential$ of $-25{\sim}-35$ mV, being maintained stable for over 6 months. However, the $TiO_2$ sol added with Cr had a much lower value of -potential and larger particle sizes. The coated $TiO_2$ thin films had almost the same shape and size as those of the sol. The pure $TiO_2$ sol showed the highest optical absorption in the ultraviolet light region, and other $TiO_2$ sols containing $Cr^{3+},\;Fe^{3+}\;and\;Ni^{2+}$ showed higher optical absorption than pure sol in the visible light region. According to the experiments for removal of a gas-phase benzene, the pure $TiO_2$ film showed the highest photo dissociation rate in the ultraviolet light region, but in artificial sunlight the photo dissociation rate of $TiO_2$ coated films containing $Cr^{3+},\;Fe^{3+}\;and\;Ni^{2+}$ was measured higher together with the increase of optical absorption by doping.