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Characterization of Fe-ACF/$TiO_2$ composite Photocatalysts Effect Via Degradation of MB Solution (Fe-ACF/$TiO_2$ 복합체의 특성과 MB용액의 분해에서 포토-펜톤 효과)

  • Zhang, Kan;Meng, Ze-Da;Ko, Weon-Bae;Oh, Won-Chun
    • Elastomers and Composites
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    • v.44 no.3
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    • pp.290-298
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    • 2009
  • In this paper, the Fe-activated carbon fiber (ACF)/$TiO_2$ composite catalysts were prepared by a sol-gel method. The synthesized photocatalysts were used for the photo degradation of Methylene blue solution under UV light. From Brunauer-Emmett-Teller measurements (BET) data, it was shown the blocking of the micropores on the surface of ACF by treatment of Fe and Ti compound. As shown in SEM images, the ferric compounds and titanium dioxides were fixed onto the ACF surfaces. The result of X-ray powder diffraction showed that the crystal phase contained a mixing anatase and rutile structure and the 'FeO+$TiO_2$' from the composites. The EDX spectra for the elemental analysis showed the presence of C, O, and Ti with Fe peaks. Degradation activity of MB could be attributed to +OH radicals derived from electron/hole pair's reactions due to photolysis of $TiO_2$ and photo-Fenton effect of Fe.

Development of Cookies with Brewer's Yeast and Beans to Improve Skin Health of Lactating Women (피부 미용 개선을 위한 맥주 효모 및 두류 첨가 수유부용 쿠키 개발)

  • Lee, Yeonje;Kim, Dah-sol;Jung, Eun-kyung;Joo, Nami
    • Journal of the Korean Dietetic Association
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    • v.24 no.1
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    • pp.31-47
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    • 2018
  • The purpose of this research was to provide basic information for cookies made with black soybeans, chick peas, lentils, oatmeal, and brewer's yeast and to establish the optimum formula for the development of low glycemic index (GI) cookies with high biotin content for lactating women. This study was performed to determine the optimal composite recipe of oatmeal cookies with two different concentrations levels of bean powder (black soybeans, chick peas, lentils) and brewer's yeast using a central composite design. In addition, the mixing conditions of oatmeal cookies were optimized using response surface methodology of sensory evaluation and mechanical and physicochemical analysis. As a result, mechanical and physicochemical analyses showed significant values for lightness, redness, yellowness, hardness, and water content (P<0.05), while sensory evaluation showed significant values for flavor, taste, crispness, and overall acceptability (P<0.05). The optimal sensory combination was suggested to be 3.73 g of bean powder and 1.59 g of brewer's yeast. Considering all outcomes obtained throughout the experiments, brewer's yeast, black soybeans, chick peas, lentils, and oatmeal are suitable ingredients for increasing functionality and consumer acceptability of cookies. In addition, these results are expected to be useful in producing cookies of optimal quality, contributing to the development of various nutritious foods, and improving the food industry for lactating women.

The Preparation and Characteristics of Covalently Cross-Linked SPEEK/Cs-TPA/Ceria Composite Membranes for Water Electrolysis (수전해용 공유가교 SPEEK/Cs-TPA/Ceria 복합막의 제조 및 특성 연구)

  • Song, Minah;Ha, Sungin;Park, Deayong;Ryu, Cheolhwi;Moon, Sangbong;Kang, Ansoo;Chung, Janghoon
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.5
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    • pp.437-447
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    • 2012
  • Ceria ($CeO_2$) was used to scavenge free radicals which attack the membrane in the polymer electrolyte membrane water electrolysis (PEMWE) circumstance and to increase the duration of the membrane. In order to improve the electrochemical, mechanical and electrocatalytic characteristics, engineering plastic of the sulfonated polyether ether ketone (SPEEK) as polymer matrix was prepared in the sulfonation reaction of polyether ether ketone (PEEK) and the organic-inorganic blended composite membranes were prepared by sol-gel casting method with loading the highly dispersed ceria and cesium-substituted tungstophosphoric acid (Cs-TPA) with cross-linking agent contents of 0.01 mL. In conclusion, CL-SPEEK/Cs-TPA/ceria (1%) membrane showed the optimum results such as 0.130 S/cm of proton conductivity at $80^{\circ}C$, 2.324 meq./g-dry-membrane of ion exchange capacity and mechanical characteristics, and 65.03 MPa of tensile strength which were better than Nafion 117 membrane.

A Novel Synthesis and Photonic Effect of Fe-CNT/TiO2 Composites by Controlling of Carbon Nanotube Amounts

  • Zhang, Kan;Meng, Ze-Da;Oh, Won-Chun
    • Korean Journal of Materials Research
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    • v.20 no.3
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    • pp.117-124
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    • 2010
  • Titanium dioxide ($TiO_2$) particles deposited on different quantitative Fe-treated carbon nanotube (CNT) composites with high photocatalytic activity of visible light were prepared by a modified sol-gel method using TNB as a titanium source. The composites were characterized by BET, XRD, SEM, TEM and EDX, which showed that the BET surface area was related to the adsorption capacity for each composite. From TEM images, surface and structural characterization of for the CNT surface had been carried out. The XRD results showed that the Fe-ACF/$TiO_2$ composite mostly contained an anatase structure with a Fe-mediated compound. EDX results showed the presence of C, O, and Ti with Fe peaks in the Fe-CNT/$TiO_2$ composites. The photocatalytic activity of the composites was examined by degradation of methylene blue (MB) in aqueous solution under visible light, which was found to depend on the amount of CNT. The highest photocatalytic activity among the different composites was related to the optimal content of CNT in the Fe-CNT/$TiO_2$ composites. In particular, the photocatalytic activity of the Fe-CNT/$TiO_2$ composites under visible light was better than that of the CNT/$TiO_2$ composites due to the introduction of Fe particles.

Quality Characteristics of Dried Noodle Prepared with Doenjang Powder (된장분말을 첨가한 국수의 품질 특성)

  • Park, Bock-Hee;Koh, Kyeong-Mi;Cha, Min-hye;Kim, Sol;Jeon, Eun-Raye
    • Journal of the Korean Society of Food Culture
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    • v.31 no.6
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    • pp.616-623
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    • 2016
  • This study evaluated the quality characteristics of dried noodles prepared with doenjang powder (0, 3, 6, 9%) in order to determine the most preferred noodle recipe. The proximate composition of the composite doenjang powder-wheat flours was as follows: calories 365 kcal, carbohydrates 79 g, saccharides 3 g, protein 10 g, fat 0.8 g, and sodium 65 mg. As the level of doenjang powder increased, the content of total amino acids increased; aspartic acid, glutamic acid, tyrosine, and lysine contents increased, in particular. Water-binding capacity decreased as the level of doenjang powder increased. When viscosity of composite doenjang powder-wheat flours was measured by amylography, gelatinization point increased as the level of doenjang powder increased. As the level of doenjang powder increased, L value decreased, whereas a and b values increased. Weight, water absorption, and volume of cooked noodles decreased, whereas turbidity of soup increased. For textural properties, hardness decreased, whereas springiness increased as the level of doenjang powder increased. For overall preference according to the results of sensory evaluation, noodles added with 3% doenjang powder were the most preferred. According to the results, addition of doenjang powder positively affects the overall sensory evaluation of dried noodle, and 3% is the optimal level for addition.

Printability of Thermally and Chemically Stable Silica-Titanium Dioxide Composite Coating Layer (실리카-이산화티탄 복합 코팅층의 열적, 화학적 안정성 및 인쇄적성 평가)

  • Kim, Hye Jin;Han, Kyu Sung;Hwang, Kwang Taek;Nahm, Sahn;Kim, Jin Ho
    • Korean Journal of Materials Research
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    • v.29 no.10
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    • pp.631-638
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    • 2019
  • As automation systems become more common, there is growing interest in functional labeling systems using organic and inorganic hybrid materials. Especially, the demand for thermally and chemically stable labeling paper that can be used in a high temperature environment above $300^{\circ}C$ and a strong acid and base atmosphere is increasing. In this study, a composite coating solution for the development of labeling paper with excellent thermal and chemical stability is prepared by mixing a silica inorganic binder and titanium dioxide. The silica inorganic binder is synthesized using a sol-gel process and mixed with titanium dioxide to improve whiteness at high-temperature. Adhesion between the polyimide substrate and the coating layer is secured and the surface properties of the coating layer, including the thermal and chemical stability, are investigated in detail. The effects of the coating solution dispersion on the surface properties of the coating layer are also analyzed. Finally, it is confirmed that the developed functional labeling paper showed excellent printability.

Relative Photonic Properties of Fe/TiO2-Nanocarbon Catalysts for Degradation of MB Solution under Visible Light

  • Oh, Won-Chun;Zhang, Feng-Jun;Meng, Ze-Da;Zhang, Kan
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1128-1134
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    • 2010
  • Nanocarbon supported Fe/$TiO_2$ composite catalysts were prepared using CNTs (carbon nanotubes) and $C_{60}$ (fullerene) as nanocarbon sources by a modified sol-gel method. The Fe/$TiO_2$-nanocarbon composites were characterized by the BET surface area, scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) and UV-vis spectra. In comparison with non-nanocarbon doped Fe/$TiO_2$ composites, the nanocarbon supported Fe/$TiO_2$ composites had higher absorption ability with a larger specific surface area, and showed higher photocatalytic activity during the degradation of methylene blue (MB) under visible light. The reasons for the obvious increase of photocatalytic activity indicated that the photoactivity not only benefits from nanocarbon introduced, but also relates to the cooperative effect of the Fe as a dopant.

Synthesis of Aluminum Nitride Powder from Aluminum Hydroxide by Carbothermal Reduction-Nitridation (알루미나 수화물로부터 탄소환원질화법에 의한 질화알루미늄 분말의 합성)

  • 황진명;정원중;최상욱
    • Journal of the Korean Ceramic Society
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    • v.31 no.8
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    • pp.893-901
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    • 1994
  • In this study, AlN powder of fine particle size and of high purity was synthesized by the carbothermal reduction-nitridation of monodisperse, spherical Al(OH)3 which had been prepared by sol-gel method using Al(O-sec-C4H9)3 as the starting material. Depending on the mixing order and kinds of reducing agents, the optimum condition for the preparation of AlN was determined as follows. AlN single-phase was produced by the carbothermal reduction-nitridation of (1) Benzene-washed Al(OH)3 and the reducing agent, carbon, which was mixed in a ball mill: for 5 hours at 140$0^{\circ}C$ under NH3 atmosphere; (2) The mixture prepared by hydrolysis of alkoxide solution into which carbon had been dispersed beforehand: for 5 hours at 135$0^{\circ}C$ ; (3) Al(OH)3 Poly(furfuryl alcohol) composite powder: for 2.5 hours at 135$0^{\circ}C$; (4) The mixture of Al(OH)3 and polyacrylonitrile: for 5 hours at 140$0^{\circ}C$. Addition of CaF2 increased the nitridation rate when carbon or polyacrylonitrile was used as the reducing agent; but it had no effect on the nitridation rate when furfuryl alcohol was used as the reducing agent.

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Effect of ACF and WO3 from ACF/WO3/TiO2 Composite Catalysts on the Photocatalytic Degradation of MO Under Visible Light

  • Meng, Ze-Da;Song, Da-Ye;Zhu, Lei;Park, Chong-Yeon;Choi, Jong-Geun;Oh, Won-Chun
    • Journal of the Korean Ceramic Society
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    • v.48 no.4
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    • pp.282-287
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    • 2011
  • ACF and $WO_3$ modified $TiO_2$ composites (ACF/$WO_3$/$TiO_2$) were prepared using a sol-gel method. The composites were characterized by Brunauer.Emmett.Teller (BET) surface area measurements, X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis and scanning electron microscope (SEM) analysis. A methyl orange (MO) solution under visible light irradiation was used to determine the photocatalytic activity. The degradation of the MO was determined using UV/Vis spectrophotometry. An increase in photocatalytic activity was observed and attributed to an increase of the photo-absorption effect by the $WO_3$ and the cooperative effect of the ACF.

Effect of Heat-Treated Temperature on Surface Crystal Structure and Catalytic Activity of ACF/ZnO Composite under Ultraviolet Irradiation and Ultrasonication

  • Zhang, Kan;Oh, Won-Chun
    • Journal of the Korean Ceramic Society
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    • v.47 no.2
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    • pp.136-141
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    • 2010
  • ACF/ZnO photocatalyst was synthesized by a sol-gel method using activated carbon fiber (ACF) and Zn $(NO_3)_2$ as precursors. Samples were characterized by Brunauer-Emmett-Teller measurements (BET), scanning electron microscope (SEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX). The XRD results showed that ACF/ZnO composites only included a hexagonal phase by heat-treated temperature at $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, and $700^{\circ}C$. The SEM analysis revealed that the ACF/ZnO composites did not exhibit any morphological changes of the catalyst surface according to the different heat-treated temperatures. The photocatalytic activity of the samples was tested for degradation of methylene blue (MB) solutions under ultraviolet (UV) light and ultrasonication respectively. The results showed that the photocatalytic activity of ACF/ZnO composites heat-treated at $500^{\circ}C$ was higher than other samples, which is ascribed to the fine distribution of ZnO particles on the surface of the ACF. In addition, an ultrasound of low power (50 W) was used as an irradiation source to successfully induce ACF/ZnO composites to perform sonocatalytic degradation of MB. Results indicated that the sonocatalytic method in the presence of ACF/ZnO composites is an advisable choice for the treatments of organic dyes.