• Bulletin of the Korean Space Science Society
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• 1997.04a
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• pp.11.2-11
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• 1997

• Bulletin of the Korean Space Science Society
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• 1997.04a
• /
• pp.12.2-12
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• 1997

• Bulletin of the Korean Space Science Society
• /
• 1997.04a
• /
• pp.13.2-13
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• 1997

• The Bulletin of The Korean Astronomical Society
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• v.22
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• pp.7.1-7.1
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• 1997

• The Bulletin of The Korean Astronomical Society
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• v.23
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• pp.41-41
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• 1998

• Publications of The Korean Astronomical Society
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• v.13 no.1 s.14
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• pp.129-134
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• 1998

Observations of the J=1-0 transition line of HCN were made at the center of Comet C/1995 O1 (Hale-Bopp) from November, 1996 to April, 1997 with the 14-m radio telescope at the TRAO (Taeduk Radio Astronomical Observatory). From the obtained data, an HCN production rate at each observed date was derived. The rapid variation of the HCN production rate near the perihelion was detected, and it is thought to be caused by jet(s) from the nucleus. The correlation between the visual magnitude and the HCN production rate is found to be $Q_{HCN}=27.03-0.11(m_v-5log{\Delta})$.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.363-364
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• 1996

• Bulletin of the Korean Space Science Society
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• 1996.11a
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• pp.25-25
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• 1996

No Abstract, See Full Text

• Polymer(Korea)
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• v.30 no.4
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• pp.298-304
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• 2006

Blends of poly (acrylic acid-co-maleic acid)(PAM) with poly (vinyl alcohol)(PVA) were obtained by solution blending. The blends were solvent-on to a film to examine thermo-mechanical properties and gas permeability. The transition temperatures $(T_g\;and\;T_m)$ of the blends remained constant regardless of PAM contents. However, the values of enthalpy changes corresponding to melting transition $({\Delta}H_m)$ and initial degradation temperature $({T_D}^i)$ were decreased with increasing PAM content. The values of ultimate strength and initial modulus gave the maximum value at the 12 wt% PAM then decreased with further increase of PAM content up to 15 wt%. To measure the gas permeability of the PVA/PAM blend films, the PVA blend solutions were coated onto both biaxially oriented propylene (BOPP) and poly (ethylene terephthalate)(PET) films. The oxygen transmission rate $(O_2\;TR)$ permeability values mono- tonically decreased with increasing PAM content. However, moisture vapor transmission rate was not affected by PAM content.

• Journal of Adhesion and Interface
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• v.23 no.3
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• pp.94-99
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• 2022

Ternary phased graphene/silica/EVOH nanocomposite coating materials were prepared via sol-gel process and solution blending process. From both SEM observations and XRD analysis, the exfoliated structure and dispersion state of graphene nanosheets and silica particles in the nanocomposites as well as the intercalated and exfoliated structure of the prepared graphene oxide were confirmed. The incorporation of GrO and silica at appropriate content resulted in remarkable improvement in oxygen barrier property of the ternary phased nanocompoiste-coated BOPP films, compared with that of binary(silica/EVOH) phased nanocomposite coating films, however, at excess amount of GrO and silica, very slight variation was observed due to incomplete exfoliation, dispersion of graphene tactoids, and formation of micro cracks in the silica clusters. In addition, the transparency of nanocomposite-coated film was investigated by measuring the light transmittance as a function of GrO contents, suggesting the possibility for the application of food packaging films.