• Title/Summary/Keyword: Catalyst-free

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The Meaning of Experiences for mothers with young children by Participating in voluntary Small Groups (영유아기 자녀를 둔 어머니의 자발적 소모임 참여 경험의 의미 탐색)

  • Chung, Kai Sook;Park, Ji Yeong;Ryu, Su Min
    • Korean Journal of Childcare and Education
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    • v.12 no.5
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    • pp.91-113
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    • 2016
  • This study aims to find out the significance in the experiences of voluntary participation in small groups by mothers of young children. As a result of the interviews conducted by targeting five mothers, the total was divided into three categories and six sub-factors. First, mothers voluntarily participated in small groups. Free from the role of mother and wife, they focused on their real selves, and had experiences of emotional support by forming close relationships with people. Second, mothers did not just participate in small groups as a hobby, but tried to be role models that help the growth of their children. They also tried to be the catalyst that helps create positive changes in their children and husbands. Third, mothers had social experiences, participated in economic activities as members of society or exerted their capabilities through active exchange with other people. Finally, this research hopes to provide the community with parent education-related implications that can have a positive impact on mothers themselves, their families and society.

Improvement of Wrinkle Recovery and Functional Properties in Linen Fabrics (아마직물의 방추성과 복합기능성 향상을 위한 연구)

  • Kang, Mi-Jung;Kwon, Young-Ah
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.11
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    • pp.1859-1869
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    • 2010
  • This study provides improved wrinkle recovery and UV protection capabilities as well as an antibacterial and deodorizing function to linen fabrics for summer shirts. The results obtained from this study are as follows. By setting catalyst concentration to 1.2% and DMDHEU concentration to 6% respectively and applying a heat treatment to them at $160^{\circ}C$ for 5 minutes, the decrease of fabric strength could be minimized and the crease resistance of linen fabrics improved. Compared to the treatment with DMDHEU only, the crease resistance of linen fabrics could be maintained and degradation of their properties could be more effectively prevented by applying the mixture of the UV absorber and the nano silver to the DMDHEU resin. The UV protection of fabrics could be improved by adding the UV absorber. Although the separate treatment of resin or the nano silver had no effect on the improvement of the UV protection properties for treated fabrics, they could increase the UV protection capability when they were combined with the UV absorber. Linen fabrics could possess an antibiosis and deodorizing capability by applying the mixture of the UV absorber, the nano silver, and the resin. The UV protection, crease resistance and flexibility of finished fabrics were maintained even after laundering. Washed treated fabrics maintained excellent antibiosis and odor free capabilities compared to untreated fabrics.

Experimental and Theoretical Studies on the Tautomerism in 2-Aminopyridines and 2(1H)-Pyridinones: Synthesis of 2-Amino-4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)pyridines and 4-Aryl-3-cyano-6-(3,4-dimethoxyphenyl)-2(1H)-pyridinones

  • Davoodnia, Abolghasem;Attar, Paria;Morsali, Ali;Eshghi, Hossein;Tavakoli-Hoseini, Niloofar;Khadem, Shahriar
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1873-1878
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    • 2011
  • Under solvent-free conditions and in one-pot, a series of 2-amino-4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)-pyridines and 4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)-2(1H)-pyridinones were prepared using 3,4-dimethoxyacetophenone, an aldehyde, malononitrile (or ethyl cyanoacetate), and ammonium acetate in the presence of 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogen sulfate $[HO_3S(CH_2)_4MIM][HSO_4]$ (a Br${\o}$nsted acidic ionic liquid) as the catalyst in very short reaction time. The preference for the formation of more stable tautomers was consistence with the theoretical calculation using the Gaussian 03 program at the B3LYP hybrid density functional level.

The Study on the Reformative Costume of Gustav Klimt (구스타브 클림트[Gustav Klimt]의 개혁의상에 관한 연구)

  • Kim Sun-Young
    • Journal of the Korean Society of Costume
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    • v.56 no.4 s.103
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    • pp.1-14
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    • 2006
  • This paper is a perspectiveon the reformative costume expressed by Gustav Klimt who led the Secession Movement as a great master in Vienna. Klimt actively expressed a new costume style in his paintings, which influenced heavily on the modern costume design. This paper may contribute to reestablish the constructive direction for the 21st century fashion design based on Klimt's pursuing holistic art concept. The reformative costume in Klimt's paintings has two characteristics; ornamentism, eroticism, and reformativeness. Ornamentism is expressed with fantastic colors, various motives, exotic features, simple style clothes, and so on. Klimt used independent ornaments to express carnal desires metaphorically, which set ornaments free to lead spectators to the dreamy or elusive state and even have spectators indulged in ecstasy. As the Secession Movement focused on reforming all areas of life artistically, the costumes of Klimt's paintings symbolically express the reformativeness; he portrayed the woman in the early 20th century and sought to reform its contemporary value as a visual sensuality. Klimt tried to disrupt from the former era by over-emphasizing eroticism. The erotic expression with the colors and the style of ornaments substitute naturally for suggestive eroticism of the feminine body. With has creativity, Klimt has spectators extract the various senses from the female image in his paintings. Klimt's creative spirit on the holistic art concept could be helpful to develop a unique design as a catalyst foreseeing over the present.

Controllability of Structural, Optical and Electrical Properties of Ga doped ZnO Nanowires Synthesized by Physical Vapor Deposition

  • Lee, Sang Yeol
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.3
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    • pp.148-151
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    • 2013
  • The control of Ga doping in ZnO nanowires (NWs) by physical vapor deposition has been implemented and characterized. Various Ga-doped ZnO NWs were grown using the vapor-liquid-solid (VLS) method, with Au catalyst on c-plane sapphire substrate by hot-walled pulsed laser deposition (HW-PLD), one of the physical vapor deposition methods. The structural, optical and electrical properties of Ga-doped ZnO NWs have been systematically analyzed, by changing Ga concentration in ZnO NWs. We observed stacking faults and different crystalline directions caused by increasing Ga concentration in ZnO NWs, using SEM and HR-TEM. A $D^0X$ peak in the PL spectra of Ga doped ZnO NWs that is sharper than that of pure ZnO NWs has been clearly observed, which indicated the substitution of Ga for Zn. The electrical properties of controlled Ga-doped ZnO NWs have been measured, and show that the conductance of ZnO NWs increased up to 3 wt% Ga doping. However, the conductance of 5 wt% Ga doped ZnO NWs decreased, because the mean free path was decreased, according to the increase of carrier concentration. This control of the structural, optical and electrical properties of ZnO NWs by doping, could provide the possibility of the fabrication of various nanowire based electronic devices, such as nano-FETs, nano-inverters, nano-logic circuits and customized nano-sensors.

Synthesis and Thermal Characteristics of Nano-Aluminum/Fluorinated Polyurethane Binders (나노 알루미늄/불소 함유 폴리우레탄 결합제의 합성 및 열적 특성 연구)

  • Lan, Qianqian;Kim, Jin Seuk;Kwon, Younghwan
    • Journal of the Korean Society of Propulsion Engineers
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    • v.20 no.5
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    • pp.40-50
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    • 2016
  • Energetic plasticizers containing explosophore groups such as $-NO_2$, $-ONO_2$, and $-N_3$ group are susceptible to impact, shock, heat, etc, finally deteriorating the insensitivity of PBXs. In this study, in an attempt to investigate the feasibility of replacing sensitive explosophore groups to fundamentally inactive but potentially (latent) energetic fluorine group which was known to have an exothermic thermite reaction with aluminum, nano-aluminum/fluorinated polyurethane binders were prepared by simultaneous polyurethane and catalyst-free azide-alkyne click reaction in the presence of nano-aluminum. Thermal characteristics of nano-aluminum/fluorinated polyurethane binders were monitored by using DSC with high pressure crucible pan.

Pretargeting : A concept refraining traditional flaws in tumor targeting

  • Bhise, Abhinav;Yoo, Jeongsoo
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.6 no.1
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    • pp.53-58
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    • 2020
  • Pretargeting is a two-component strategy often used for tumor targeting to enhance the tumor-to-background ratio in cancer diagnosis as well as therapy. In the multistep strategy, the highly specific unlabeled monoclonal antibodies (mAbs) with the reactive site is allowed to get localized at tumor site first, and then small and fastclearing radiolabeled chelator with counter reactive site is administered which covalently attaches to mAbs via inverse electron demand Diels-Alder reaction (IEDDA). The catalyst-free IEDDA cycloaddition reaction between 1,2,4,5-tetrazines and strained alkene dienophiles aid with properties like selective bioconjugation, swift and high yielding bioorthogonal reactions are emergent in the development of radiopharmaceutical. Due to its fast pharmacokinetics, the in vivo formed radioimmunoconjugates can be imaged at earlier time points by short-lived radionuclides like 18F and 68Ga; it can also reduce radiation damage to the normal cells. Ultimately, this review elucidates the updated status of pretargeting based on antibodies and IEDDA for tumor diagnosis (PET and SPECT) and therapy.

Preparation of pitch from pyrolized fuel oil by electron beam radiation and its melt-electrospinning property

  • Jung, Jin-Young;Lee, Young-Seak
    • Carbon letters
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    • v.15 no.2
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    • pp.129-135
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    • 2014
  • Spinnable pitch for melt-electrospinning was obtained from pyrolized fuel oil by electron beam (E-beam) radiation treatment. The modified pitch was characterized by measuring its elemental composition, softening point, viscosity, molecular weight, and spinnability. The softening point and viscosity properties of the modified pitch were influenced by reforming types (heat or E-beam radiation treatment) and the use of a catalyst. The softening point and molecular weight were increased in proportion to absorbed doses of E-beam radiation and added $AlCl_3$ due to the formation of pitch by free radical polymerization. The range of the molecular weight distribution of the modified pitch becomes narrow with better spinning owing to the generated aromatic compounds with similar molecular weight. The diameter of melt-electrospun pitch fibers under applied power of 20 kV decreased 53% ($4.7{\pm}0.9{\mu}m$) compared to that of melt-spun pitch fibers ($10.2{\pm}2.8{\mu}m$). It is found that E-beam treatment for reforming could be a promising method in terms of time-savings and cost-effectiveness, and the melt-electrospinning method is suitable for the preparation of thinner fibers than those obtained with the conventional melt-spinning method.

Experiment of CO Cleaning Process in DME Autothermal Reformate Gas for PEMFC Application (고분자 전해질 연료전지 적용을 위한 DME 자열개질가스 내 CO제거 공정 특성 연구)

  • Choi, Seung-Hyeon;Bae, Joong-Myeon
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.4
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    • pp.474-480
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    • 2011
  • Hydrocarbon is required to be converted to pure hydrogen without carbon monooxide (CO) for polymer exchange membran fuel cell (PEMFC) applications. In this paper, CO cleaning processes as the downstream of Dimethyl ehter (DME) autothermal reforming process were performed in micro-reactors. Our study suggested two kinds of water gas shift (WGS) reaction process: High Temperature shift (HTS) - Low Temperature shift (LTS), Middle temperature shift (MTS). Firstly, using perovskite catalyst for MTS was decreased effieiciency since methanation. Using HTS-LTS the CO concentration was decreased about 2% ($N_2$ & $H_2O$ free) with the reaction temperature of $420^{\circ}C$ and $235^{\circ}C$ for HTS and LTS, respectively. As the final stage of CO cleaning process, preferential oxidation (PROX) was applied. The amount of additional oxygen need 2 times of stoichiometric at $65^{\circ}C$. The total conversion reforming efficiency of 75% was gained.

Growth and Characterization of P-type Doping for InAs Nanowires during Vapor-liquid-solid and Vapor-solid Growth Mechanism by MOCVD

  • Hwang, Jeongwoo;Kim, Myung Sang;Lee, Sang Jun;Shin, Jae Cheol
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.328.2-328.2
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    • 2014
  • Semiconductor nanowires (NWs) have attracted research interests due to the distinct physical properties that can lead to variousoptical and electrical applications. In this paper, we have grown InAs NWs viagold (Au)-assisted vapor-liquid-solid (VLS) and catalyst-free vapor-solid (VS) mechanisms and investigated on the p-type doping profile of the NWs. Metal-organic chemical vapor deposition (MOCVD) is used for the growth of the NWs. Trimethylindium (TMIn) and arsine (AsH3) were used for the precursor and diethyl zinc (DEZn) was used for the p-type doping source of the NWs. The effectiveness of p-type doping was confirmed by electrical measurement, showing an increase of the electron density with the DEZn flow. The structural properties of the InAs NWs were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition, we characterize atomic distribution of InAs NWs using energy-dispersive X-ray spectroscopy (EDX) analysis.

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