• Polymer(Korea)
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• v.26 no.5
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• pp.559-567
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• 2002

Poly (vinyl chloride) was blended with blended with vinyl chloride-acrylonitrile copolymers (MO-01 : M$\sub$w/=199049, AN=22.79%, MO-02 : M$\sub$w/=238523, AN=47.03%, MO-03 : M$\sub$w/=289496, AN=52.49%, MO-04 : M$\sub$w/=341837, AN=58.68% by mixing dimethylformamide (DMF) solution of each polymer and their morphology, viscosity, viscoelastic and mechanical properties were studied. Blends of PVC and MO-01 showed a homogeneous morphology. On the contrary, the other copolymer blends showed a large phase separation with spherical domains. Miscibility of blends of PVC and MO-01 was shown to be better than that of blends of other copolymers from morphological and viscoelastic studies. Even though blends of PVC and MO-01 were observed to be the considerable compatibility at a composition of PVC/MO-01=90/10, the mechanical properties of blend films were not improved too much in most blend cases.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1699-1702
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• 2012

$TiO_2$ nanostructures with various morphologies like cubes, spheres, hexahedral pillars and spherical tubes were synthesized by microwave-assisted hydrothermal process. Each structure was obtained by changing the relative concentrations of titanium tetraisoproxide (TTIP), tetrabutylammonium hydroxide (TBAH) and ethanol. Scanning electron microscopy (SEM), transmission electoron microscopy (TEM), X-ray diffraction and Brunauer-Emmett-Teller (BET) surface area analysis were used to characterize the synthesized $TiO_2$ nanostructures. From these results, it has been proved that $TiO_2$ structure could be controlled to have specific morphology, size, surface area, pore volume and pore size distribution.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.5
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• pp.219-223
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• 2014

Pulsed laser ablation in liquid medium was successfully employed to synthesize hydroxyapatite colloidal nanoparticles. The crystalline phase, particle morphology, size distribution and microstructure of the hydroxyapatite nanoparticles were investigated in detail. The obtained hydroxyapatite nanoparticles had spherical shape with sizes ranging from 5 to 20 nm. The laser ablation and the nanoparticle forming process were discussed with explosive ejection mechanism by investigating change of surface morphology on target. The analytical results of XPS, FT-IR and Raman spectroscopy confirms that the stoichiometry and bonding properties of the hydroxyapatite nanoparticles are in good agreement with reported bulk hydroxyapatite materials.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.286-286
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• 2006

We report on a fascinating morphology; giant spherical conducting polythiophene by the in-situ gamma radiation-induced chemical polymerization method. The resultant micron-size buckyball-shaped polymer structures were identified by high resolution transmission electron microscopy and scanning electron microscopy. Different characterizations e.g. Fourier transform infrared, x-ray diffraction, and x-ray photoelectron microscopy were utilized to prove that the new morphological conducting polythiophene was synthesized successfully by this novel method.

• Journal of Electrochemical Science and Technology
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• v.3 no.4
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• pp.172-177
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• 2012

Mo-doped $LiFePO_4$ was synthesized via co-precipitation method using sucrose as the carbon source. Structure, surface morphology, and the electrochemical properties of the synthesized olivine compounds were investigated using Rietveld refinement of X-ray diffraction data (XRD), scanning electron microscopy (SEM), and electrochemical charge-ischarge tests. Spherical morphology with the particle size of ${\sim}8{\mu}m$ authenticated the enhanced tap density and volumetric energy density of the synthesized materials. Charge-discharge behavior of $LiFePO_4$ and Mo-doped $LiFePO_4$ cells demonstrated a specific capacity of 130 and 145 mAh $g^{-1}$, respectively. Mo-doped $LiFePO_4$ cells exhibited an excellent discharge capacity at 96 mAh $g^{-1}$ at 7 C-rate.

• Journal of The Korean Astronomical Society
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• v.36 no.4
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• pp.261-270
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• 2003

We have conducted a V-band CCD surface photometry of 68 disk galaxies to analyze the bulge morphology of nearby spirals. We classify bulges into four types according to their ellipticities and the misalignments between the major axis of the bulge and those of the disk and the bar: spherical, oblate, pseudo triaxial, and triaxial. We found that one third of the bulges are triaxial and they are preponderant in barred galaxies. The presence of the triaxial bulges in a significant fraction of unbarred galaxies as well as in barred galaxies might support the secular evolution hypothesis which postulates that the bar driven mass inflow leads to the formation of triaxial bulges and the destruction of bars when sufficient mass is accumulated in the central regions.

• Macromolecular Research
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• v.16 no.1
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• pp.62-65
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• 2008

The morphology of the $D_2O$-induced reverse micellar structure of an amphiphilic block copolymer of poly( ethylene oxide )-b-poly(propylene oxide )-b-poly( ethylene oxide )($EO_{76}PO_{29}EO_{76}$) was investigated in hydrophobic media by small angle neutron scattering (SANS). Increasing $D_2O$ in the styrene/divinylbenzene solution of $EO_{76}PO_{29}EO_{76}$ led to a change in morphology of the reverse micelles from a short range ordered molecular aggregate to a hexagonally arranged micelle, and further to a spherical micelle.

• Journal of Korea Foundry Society
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• v.19 no.6
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• pp.466-471
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• 1999

To investigate inclusions(oxides) which cause some trouble in the quality of the metal and a steel-making process, samples were manufactured. The molten irons were deoxidized using Al deoxidizer, and the morphology of the deoxidation products and the process of deoxidation were investigated by optical microscope, scanning electron microscope (SEM) and energy dispersive X-ray spectrometer(EDS). The reactions between Fe melt and Al deoxidizer formed deoxidation product, and those reaction may accelerates the reduction of oxide in Fe melt. According to the results of SEM analysis after deoxidizing treatment, it was found that deoxidation products had spherical cluster shape when 1% Al was added and dendritic shape with $2{\sim}3%$ A1 addition. The deoxidation products were globular, dendritic, polygonal(square) and cluster shape.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.123-127
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• 1997

Various recrystallization techniques has been applied to control morphology and size of NTO(3-nitro-1, 2, 4-triazole-5-one) crystals. With cooling method, it was found that the size of NTO at aqueous solution was controlled in the range of 5 to 500 $\mu\textrm{m}$. The spherical or cubic shapes of particles were obtained by adjusting operating conditions. Hexagonal and cubic shaped crystals of NTO were also obtained by sonication and evaporative method using aqueous solution of NTO. Their particle sizes were ranged 20 to 30 $\mu\textrm{m}$. In gas anti-solvent method with NTO/DMF and NTO/DMSO solutions, cubic type of NTO was obtained and the range of their sizes was 0.5-2$\mu\textrm{m}$.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1266-1268
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• 2008