• Title/Summary/Keyword: naphthenate

Search Result 17, Processing Time 0.026 seconds

Preparation of $TiO_2$ thin films by coating-pyrolysis process of Ti-naphthenate (Ti-naphthenate의 코팅-열분해에 의한$TiO_2$ 박막의 제조)

  • 김진영;김승원;장우석;김현태;최상원
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.12 no.1
    • /
    • pp.7-10
    • /
    • 2002
  • $TiO_2$ thin films were prepared by coating and subsequent pyrolysis processes using Titanium-naphthenate as a raw material. $TiO_2$ thin films were made by spin-coating technique on the glass substrates, and heat treated at 45$0^{\circ}C$, The transmittance, refractive index, crystallinity and surface morphology of the $TiO_2$ thin films were measured by UV/Vis spec trophotometer, x-ray diffractometer and scanning electron microscope. $TiO_2$thin films on the slide glass showed the trans mittance of 70-90% and refractive index of 2.6 at 420 nm. The results of XRD and SEM showed that the $TiO_2$ thin films exhibited the anatase phase and the thread-like surface morphology.

Crystal structure of the epitaxial $BaTiO_{3}$ thin film on the MgO (100) substrate prepared by the coating-pyrolysis process

  • Kim, S.;Kwon, O.Y.;Choi, S.W.;Manabe, T.;Yamaguchi, I.;Kumagai, T.;Mizuta, S.
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.10 no.6
    • /
    • pp.378-380
    • /
    • 2000
  • The epitaxial $BaTiO_{3}$ thin film was prepared on the MgO substrate by the coating-pyrolysis process using a mixed solution of Ba-naphthenate and Ti-naphthenate. The crystal structure of the epitaxial $BaTiO_{3}$ thin film was characterized by XRD ${\theta}/2{\theta}$ scan and asymmetric {303} rocking curve scan. The epitaxial $BaTiO_{3}$ thin film had the cubic phase with the lattice parameter of a = c = 0.4018 nm.

  • PDF

Characteristics and Synergistic Effects of Coal/Wasted Tire/Polypropylene Coliquefaction (II) (석탄, 폐타이어, 폴리프로필렌 공동액화 특성 및 상승효과(II))

  • Jeong, Dae-Heui;Jeong, Tae-Jin;Kim, Sang-Jun;Na, Byung-Ki;Song, Hyung-Keun;Yoon, Do-Young;Kim, Dae-Heum;Han, Choon
    • Journal of Energy Engineering
    • /
    • v.10 no.4
    • /
    • pp.370-378
    • /
    • 2001
  • Characteristics and synergistic effects of the coliquefaction of Alaskan subbituminous coal, wasted tire, and polypropylene were investigated in a tubing-bomb reactor at 41$0^{\circ}C$, and the coliquefaction reactions were performed at 37$0^{\circ}C$~45$0^{\circ}C$ to evaluate the coliquefaction mechanism. The coliquefaction kinetic model based on the free-radical theory was proposed and simulated by the non-linear parameter estimation method. Simulated results represented experimental ones successfully with the correlation coefficient of 0.99. When a catalyst was not used, the conversions were decreased as tetralin increase due to the decrease of liquefaction of polypropylene. When naphthenate catalysts of Mo, Co, and Fe were used, the coliquefaction conversions were increased with the increase of the liquefaction of polypropylene. When Co-naphthenate catalyst was used, the increase of the coliquefaction conversion were as high as 21~23%.

  • PDF

Preparation of Asymmetric Ceramic Membrane by Coating-Pyrolysis Process (도포-열분해법을 이용한 비대칭 세라믹 분리막 제조)

  • Ryu, Hyun-Wook;Kim, Byung-Hoon
    • Journal of the Korean Ceramic Society
    • /
    • v.39 no.12
    • /
    • pp.1153-1157
    • /
    • 2002
  • The fabrication of a three-layered asymmetric ceramic membrane was performed by slip casting of the porous alumina support and dip coating of the alumina intermediate layer using high purity ${\alpha}-Al_2O_3$ powders that have different particle size, followed by screen printing-pyrolysis of the $Tio_2$ layer as an ultrafilteration membrane using Ti-naphthenate solution. The bending strength, porosity and mean pore size of the alumina support were 231 kg/$cm^2$s, 30.26% and 0.19 ${mu}m$, respectively. The thickness of the intermediate layer was 30 ${mu}m$ and the mean pore size of that was 0.063 ${mu}m$. Also, the top layer was 0.5 ${mu}m$ thick and micropores with about 20 nm size were formed uniformly.

Optical, Structural and Photo-catalytic properties of TiO2 thin films prepared by using Ti-naphthenate (Ti-naphthenate를 이용하여 제조한 광감응성 TiO2 박막의 광학적 및 구조적 특성)

  • Lim, Yong-Moo;Jung, Ju-Hyun;Hwang, Kyu-Seog
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.10 no.3
    • /
    • pp.185-191
    • /
    • 2005
  • Photo-reactive $TiO_2$ thin films on soda-lime-silica slide glass were prepared by spin coating technique with a Ti-naphthenate precursor. Optical, structural and photo-catalytic properties of the films after annealing at $500^{\circ}C{\sim}600^{\circ}C$ were evaluated. As increase with annealing temperature, absorption bands and total transmittance of the films showing an average transmittance (about 80%) at visible spectra range were shifted to UV spectra range and slightly decreased. Refractive index and thickness of the films were increased from 2.16 to 2.63 and decreased from 484 nm to 439 nm, respectively, with increase of annealing temperature. Anatase phase was visible at all annealing temperature. More rougher surface structure was obtained at $600^{\circ}C$ than those of films annealed at $500^{\circ}C$ and $550^{\circ}C$. The hydrophilic conversion was found within 45 min by UV stimulation and optical activation was UVC>UVA>UVB at the case of $500^{\circ}C{\sim}550^{\circ}C$ and UVA>UVC>UVB at the annealing temperature of $600^{\circ}C$. The lowest initial contact angle was obtained at $600^{\circ}C$.

  • PDF

Optical Property of Zinc Oxide Thin Films Prepared by Using a Metal Naphthenate Precursor (금속 나프텐산염을 이용하여 제조한 ZnO 박막의 광학적 특성)

  • Lim, Y.M.;Jung, J.H.;Jeon, K.O.;Jeon, Y.S.;Hwang, K.S.
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.10 no.3
    • /
    • pp.193-203
    • /
    • 2005
  • Highly c-axis oriented nanocrystalline ZnO thin films on silica glass substrates were prepared by spin coating-pyrolysis process with a zinc naphthenate precursor. Only the XRD intensity peak of (002) phase was observed for all samples. With an increase in heat treatment temperature, the peak intensity of (002) phase increases. No significant aggregation of particle was present. From scanning probe microscopy analyses, three-dimensional grain growth, which was thought to be due to inhomogeneous substrate surface and c-axis oriented grain growth of the ZnO phase, was independent on heal-treatment temperature. Highly homogeneous surface of the highly-oriented ZnO film was observed at $800^{\circ}C$. All the films exhibited a high transmittance (above 80%) in visible region except film heat treated at $1000^{\circ}C$, and showed a sharp fundamental absorption edge at about $0.38{\sim}0.40{\mu}m$. The estimated energy band gap for all the films were within the range previously reported for films and single crystal. ZnO films, consisting of densely packed grains with smooth surface morphology were obtained by heat treatment at $600^{\circ}C{\sim}800^{\circ}C$, expected to be ideal for practical application, such as transparent conductive film and optical device.

  • PDF

Preparation of Nanocrystalline ZrO2 Film by Using a Zirconium Naphthenate and Evaluation of Calcium Phosphate Forming Ability (지르코늄 나프테네이트를 이용한 나노결정질 ZrO2 박막의 제조와 칼슘 포스페이트 형성 능력의 평가)

  • Oh, Jeong-Sun;Ahn, Jun-Hyung;Yun, Yeon-Hum;Kang, Bo-An;Kim, Sang-Bok;Hwang, Kyu-Seog;Shim, Yeon-A
    • Journal of the Korean Ceramic Society
    • /
    • v.39 no.9
    • /
    • pp.884-889
    • /
    • 2002
  • In order to investigate the calcium phosphate forming ability of nanocrystalline $ZrO_2$ film, we prepared $ZrO_2/Si$ structure by using a chemical solution deposition with a zirconium naphthenate as a starting material. Precursor sol was spin-coated onto the (100)Si substrate and prefired at 500$^{\circ}C$ for 10 min in air, followed by final annealing at 800$^{\circ}C$ for 30 min in air. Crystallinity of the annealed film was examined by X-ray diffraction analysis. Surface morphology and surface roughness of the film were characterized by field emission-scanning electron microscope and atomic force microscope. After annealing, nanocrystalline $ZrO_2$ grains were obtained on the surface of the film with a homogeneous interface between the film and substrate. After immersion for 1 or 5 days in a simulated body fluid, formation of calcium phosphate was observed on $ZrO_2$ film annealed at 800$^{\circ}C$ by energy dispersive X-ray spectrometer. The fourier transform infrared spectroscopy revealed that carbonate was substituted into the calcium phosphate.

Penetrating Performance of Wood-preservatives by Ultrasonic Steeping (초음파침지처리에 의한 목재방부제의 주입성)

  • Lee, Myung Jae;Lee, Dong-Heub;Lee, Hyun-Mi;Son, Dong-Won
    • Journal of the Korean Wood Science and Technology
    • /
    • v.33 no.3 s.131
    • /
    • pp.64-71
    • /
    • 2005
  • In this study, we attempted to apply ultrasonic treatment for the preservative treatment of two softwood species, Korean pine and Japanese red pines to evaluate its effectiveness. Wood samples were submerged in oilborne preservative, copper naphthenate (NCU) and waterborne preservative, alkyl ammonium compound (AAC) and then treated with ultrasonic wave of 40 kHz, 400 W. After the treatment, the retention and penetration depth of these preservatives in the specimens were measured as a function of treatment time. Both the retention and penetration depth were continuously increased with increasing the treatment time up to 120 hours, where the retention reached about 95% by the application of AAC and the penetrating depth of 95% and 83% by the application of NCU, respectively for both species. The results of electronic microscopic observation showed that the improved retention capacity could be attributed to air deflation, wood extractive deflation working of ultrasonic wavelength, and destruction of wood pits which served as the pathway of preservatives. The results suggested that the use of ultrasonic treatment could be applied to thick wood veneers for the production of laminated wood products.

Peroxidase를 이용한 cardol의 중합과 경화 거동

  • Park, Seung-Yeong;Kim, Yong-Hwan;Ryu, Jeong-Yong;Song, Bong-Geun
    • 한국생물공학회:학술대회논문집
    • /
    • 2003.04a
    • /
    • pp.121-125
    • /
    • 2003
  • Enzymatic polymerization of cardol derived from cashew nut shell liquid have been examined. t-Butyl alcohol aqueous systems showed high yield of polycardol when SBP was as biocatalyst. Compared other solvents, peroxidase actiyity was maintained stable, which was seemed major cause. Solvent aqueous system and concentration of hydrogen peroxide were found to have an influence on the yield and molecular weight distribution of polycardol under the reaction of enzymatic polymerization using peroxidase. The polymer was subjected to the hardening by methyl ethyl ketone peroxide and cobalt naphthenate catalyst, giving a crosslinked tough film. Polycardol was cured rapidly and the hardness increased with time. Finally, the pencil scratch hardness reached to 7H, which is enough hard for industrial uses.

  • PDF

Preparation of nanocrystalline $TiO_2$ photocatalyst films by using a titanium naphthenate (티타늄 나프테네이트를 이용한 나노결정질 $TiO_2$ 광촉매 박막의 제조)

  • 이선옥;김상복;윤연흠;강보안;황규석;오정선;양순호;김병훈
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.12 no.5
    • /
    • pp.240-246
    • /
    • 2002
  • $TiO_2$ films on soda-lime-silica glasses were prepared by spin coating-pyrolysis process using titanium naphthenate as a starting material. As-deposited films were pyrolyzed at $500^{\circ}C$ for 10 min in air and annealed at 500, 550 and $600^{\circ}C$ for 30 min in air. Crystallinity of the film was investigated by X-ray diffraction analysis. A field emission-scanning electron microscope and an atomic force microscope were used for characterizing the surface morphology and the surface roughness of the film. After annealing at 550 and $600^{\circ}C$, the X-ray diffraction patterns consist of only anatase peak. Films annealed at 500 and $550^{\circ}C$ exhibited flat surfaces. While with the increase in annealing temperature to $600^{\circ}C$, the $TiO_2$ film showed abnormal growth of three-dimensional needle-shaped grains. For all samples, high transmittance, above 90 % at 500 nm, was obtained at visible range. To investigate photocatalytic properties, IR absorbance associated with the C-H stretching vibrations of a thin solution-cast film of stearic acid under 365 nm (2.4 mW/$\textrm{cm}^2$) UV irradiation was estimated.