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Freshness of 'Fuji' Apples Packed Anti-fogging Agents Film (결로 방지 필름으로 포장한 '후지' 사과의 신선도)

  • Park, Hyung-Woo;Ryu, Na-Hee
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.19 no.1
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    • pp.29-33
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    • 2013
  • This study investigated the effect of films treated with anti-fogging (LA) agent on the freshness extension of 'Fuji' Apples. Preference, weight loss, total ascorbic acid, sugar content, acidity, change of gas composition in package were evaluated during storage at $15^{\circ}C$. After 150 days of storage, the weight loss of apples in control (L), LA was 1.0 to 1.1%. Total ascorbic acid content of apples in control after 150 days was 2.09 mg/100g F.W, that of apple in LA was 2.47 mg/100g F.W. The titratable acidity of apple in LA was lower than that in control, while soluble solids content of LA was higher than that in control after 150 days. Ethylene gas adsorbability in control package was 192.2 ppm and that in LA was 195.7 ppm. It was verified that LA treated with anti-fogging agent are few different compare to control, but commerdity on the display in market was considered higher than that of non-treated anti-fogging agent.

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Preparation and Characterization of LaAlO3 Ceramics from High Energy Ball Milling Powders (고에너지 볼 밀에 의한 LaAlO3 세라믹스의 제조와 특성)

  • 최상수;서병준;여기호;정수태
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.1
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    • pp.39-45
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    • 2004
  • Fine LaAlO$_3$ powders wore successfully synthesized from La$_2$O$_3$ and ${\gamma}$ $Al_2$O$_3$ powders milling for 10∼50 hours via the high energy milling technique (mechanochemical method) in room temperature and air. The particle size of LaAlO$_3$ powder were estimated from XRD patterns and SEM images to be 160∼180 nm. The LaAlO$_3$ ceramics arc derived for the synthesized powders (milling for 10, 30 and 50 hours) by sintering at 140$0^{\circ}C$ and 150$0^{\circ}C$. The micrographs of grains showed an agglomeration and the degree of agglomeration increased with the milling time. The LaAlO$_3$ made from synthesized powders milling for 50 hours can be sintered to 99.5% of theoretical density at 150$0^{\circ}C$ for 1 hour. These ceramics exhibits a dielectric constant of 20, a dielectric loss of 0.0003 and a temperature coefficient of capacitance of 15 ppm/$^{\circ}C$ at 1 MHz.

Relationship between Typhoon and El Niño·La Niña Events (태풍과 엘니뇨·라니냐 현상과의 관계)

  • Seol, Dong-Il
    • Journal of Navigation and Port Research
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    • v.37 no.6
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    • pp.611-616
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    • 2013
  • This paper studies relationship between typhoon and El Ni$\tilde{n}$o La Ni$\tilde{n}$a events by using 25 years meteorological data of KMA and JMA. The results are listed below. Annual mean number of typhoon's occurrence in El Ni$\tilde{n}$o event year is 23.9, and that in La Ni$\tilde{n}$a event year is 24.9. The number of typhoon's occurrence decreases in El Ni$\tilde{n}$o event year. Mean central minimum pressure and mean maximum wind speed in El Ni$\tilde{n}$o event year are 959.3hPa and 35.8m/s, and those in La Ni$\tilde{n}$a event year are 965.5hPa and 33.7m/s respectively. Intension of typhoon is stronger in El Ni$\tilde{n}$o event year than La Ni$\tilde{n}$a event year. To be more specific mean central minimum pressure is lower 6.2hPa and mean maximum wind speed is stronger 2.1m/s. This result is closely connected with sea area of typhoon's occurrence. Typhoons in El Ni$\tilde{n}$o event year are more likely to occur in east of 150E and south of 10N, but those in La Ni$\tilde{n}$a event year are more likely to occur in 120-150E and north of 20N. Typhoons which occur in east of 150E and south of 10N can be stronger because the typhoons move in broad sea area of high sea surface temperature in western North Pacific.

Mechanochemical Synthesis of LaNiO3 Crystalline Phase from Mixture of La2O3sub> and NiO (La2O3의 메카노케미컬 합성에 의한 LaNiO3결정상 생성)

  • 김대영;김강언;이명교;정수태
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.8
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    • pp.681-687
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    • 2003
  • The syntheses of LaNiO$_3$Perovskite crystalline phase from mixtures of La$_2$O$_3$and NiO via it mechanochemical(used planetary mill) and a wet ball mill process were investigated. A single and stable LaNiO$_3$perovskite crystalline phase was successfully prepared by using a heat free mechanochemical process which produced a fine amorphous powder, while that phase was not formed in a wet ball mill process which needed heat treatment ranging from 500 to 150$0^{\circ}C$ and produced a coarse powder. It was shown that the LaNiO$_3$ceramics made of the mechanochemically synthesized powder possesed a good metallic characteristic.

Patterning of BiLaO film using imprinting process for liquid crystal display (임프린팅을 이용한 BiLaO 패터닝과 액정 디스플레이 소자의 응용)

  • Lee, Ju Hwan
    • Journal of IKEEE
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    • v.25 no.1
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    • pp.64-68
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    • 2021
  • We demonstrate an effect of annealing temperature on imprinting process of BiLaO thin film for liquid crystal alignment. BiLaO prepared sol-gel process was deposited by spin coating on a glass substrate, and then transferred to a pre-fabricated aligned pattern which is fabricated on a silicon wafer by laser interference lithography. Thin film was annealed at different temperature of 100, 150, 200, and 250 ℃. From the polarized optical microscopy analysis, the liquid crystal orientation was not uniform at the annealing temperature of 200 ℃ or lower and the uniform liquid crystal alignment characteristics were confirmed at the annealing temperature of 250 ℃. From atomic force microscopy, the pattern was not transferred at a temperature of 200 ℃ or lower. In contrast, the pattern was transferred at 250 ℃. Anisotropy of the thin film was obtained by the alignment pattern transferred at a temperature of 250 ℃, and the liquid crystal molecules could be evenly oriented on the thin film. Therefore, it was confirmed that the liquid crystal alignment process by the imprinting process of the BiLaO oxide film was affected by the annealing temperature.

Gas sensing characteristics of $LaCoO_3$ thick-films ($LaCoO_3$ 후막의 가스 감지 특성)

  • Shin, Jeong-Ho;Jang, Jae-Young;Ma, Tae-Young;Park, Ki-Cheol;Kim, Jeong-Gyoo
    • Journal of Sensor Science and Technology
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    • v.8 no.6
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    • pp.454-460
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    • 1999
  • $LaCoO_3$ thick-films for gas sensing layers were prepared on alumina substrate by screen printing method. The sensitivities to $C_4H_{10}$, $NH_3$, NO and CO gases were investigated for different heat treatment temperatures of the films. Their structural properties were examined by X-Ray Diffraction measurements and SEM photographs. The sensitivity of $LaCoO_3$ thick-film to CO gas was much higher than those of $C_4H_{10}$, $NH_3$, and NO gases. The optimal heat treatment and operating temperatures were $800^{\circ}C$ and $150^{\circ}C$, respectively. The sensitivities of $LaCoO_3$ thick-films to 500ppm and 1250ppm CO gas were 72% and 95%, respectively.

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Comparative studies of the mechanochemically treatment of $La_{2}O_{3}-Al(OH)_{3}$ (메카노케미컬 공정에 의한 $La_{2}O_{3}-Al_{2}O_{3}$$La_{2}O_{3}-Al(OH)_{3}$의 비교연구)

  • 조정호;최상수;김강언;정수태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.701-704
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    • 2001
  • The dielectric and sintering properties of LaAlO$_3$ceramics synthesised with La$_2$O$_3$-Al$_2$O$_3$(LAO) and La$_2$O$_3$-Al(OH)$_3$(LAH) were investigated. In case of LAH samples, a single phase of LaAlO$_3$powders was formed at 100$0^{\circ}C$, density of the ceramics sintered at 140$0^{\circ}C$ was 6.41g/㎤, and the dielectric constant and loss were 22.4 and 0.003, respectively. In case of LAO samples, a single phase of LaAlO$_3$powders was formed at 130$0^{\circ}C$, density of the ceramics sintered at 150$0^{\circ}C$ was 6.35g/㎤, and the dielectric constant and loss were 22.16 and 0.009, respectively.

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Control of Working Temperature of Isothermal Magnetic Entropy Change in La0.8Nd0.2(Fe0.88Si0.12)13 by Hydrogen Absorption for Magnetic Refrigerants

  • Fujieda, S.;Fujita, A.;Fukamichi, K.;Suzuki, S.
    • Journal of Magnetics
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    • v.18 no.2
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    • pp.150-154
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    • 2013
  • $La_{1-z}Nd_z(Fe_{0.88}Si_{0.12})_{13}$ and their hydrides were investigated to obtain large magnetocaloric effects (MCEs) in a wide temperature range, including room temperature, for applications in magnetic refrigents. Since the magnetization change due to the itinerant-electron metamagentic (IEM) transition for $La_{1-z}Nd_z(Fe_{0.88}Si_{0.12})_{13}$ becomes larger with increasing z, the isothermal magnetic entropy change ${\Delta}S_m$ and the relative cooling power (RCP) are enhanced. In addition, the Curie temperatrue $T_C$ of $La_{0.8}Nd_{0.2}(Fe_{0.88}Si_{0.12})_{13}$ is increased from 193 to 319 K by hydrogen absorption, with the IEM transition. The maximum value of $-{\Delta}S_m$, $-{\Delta}S{_m}^{max}$, in a magnetic field change of 2 T for $La_{0.8}Nd_{0.2}(Fe_{0.88}Si_{0.12})_{13}H_{1.1}$ is about 23 J/kg K at $T_C$ = 288 K, which is larger than that of 19 J/kg K at $T_C$ = 276 K for $La(Fe_{0.88}Si_{0.12})_{13}H_{1.0}$. The value of RCP = 179 J/kg of the former is also larger than 160 J/kg of the latter. It is concluded that the partial substitution of Nd improves MCEs in a wide temperautre range, including room temperature.

Synthesis of Ultrafine LaAlO$_3$ Powders with Good Sinterability by Self-Sustaining Combustion Method Using (Glycine+Urea) Fuel ((Glycine+Urea) 혼합연료를 이요한 자발착화 연소반응법에 의한 우수한 소결성의 초미분체 LaAlO$_3$ 분말 합성)

  • Nam, H.D.;Choi, W.S.;Lee, B.H.;Park, S.
    • Journal of the Korean Ceramic Society
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    • v.36 no.2
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    • pp.203-209
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    • 1999
  • LaAlO3d single phase used as the butter layer on Si wafer for YBa2Cu3O7-$\delta$ superconductor application were prepared by solid state reaction method and by self-sustaining combustion process. The microstructure and crystallity of synthesiszed LaAlO3 powder studied using scanning electron microscope (SEM) and X-ray diffractometer(XRD), specific surface area and sintering characteristics fo powder were investigated by Brunauer-Emmett-Teller (BET) method and dilatometer respectively. In solid state reaction method, it is difficult to obtain LaAlO3 single phase up to 150$0^{\circ}C$ period. However, in self-sustaining combustion process, it is to easy to do it only $650^{\circ}C$. Based on the results of analysis of dilatometer it is easier to obtain high sintering density (98.87%) in self-sustaining combustion process than in the solid state reaction method. This reason is that the average particle size prepared by self-sustaining combustion process is nano crystal size and has high specific surface are value(56.54 $m^2$/g) compared with that by solid state reaction method. Also, LaAlO3 layer on the Si wafer has been achieved by screen printing and sintering method. Even though the sintering temperature is 130$0^{\circ}C$, the phenomena of silicon out diffusion in LaAlO3/Si interphase are not observed.

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