• Journal of Ocean Engineering and Technology
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• v.15 no.3
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• pp.58-62
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• 2001

The objective of research is to clarify the interaction between dislocations and precipitates during high temperature creep deformation behaviors of high n austenitic steels. After measuring the internal stress in minimum creep rate state under applied stress of 236MPa at 873K, a transmission electron microscope (TEM) observation was performed to investigate the interaction between dislocations and precipitates during high temperature creep deformation. The band widths and values of internal stress increased when the nitride precipitates distribute more densely. Fine nitrides disturbed the dislocation movement with pinning the dislocations and perfect dislocations were separated into Shockley partial dislocations by fine nitrides. Coarse nitrides disturbed the dislocation movement with climb mechanism.

• Journal of the Korean Ceramic Society
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• v.40 no.5
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• pp.460-467
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• 2003

Al-SiC$_{p}$ composite layer was prepared by plasma thermal spray on aluminum substrate using composite powder prepared by mechanical alloying. Mechanically alloyed powder was achieved after 24 h milling, which was used for thermal spray coating. The correlations between process conditions and thickness/porosity were analyzed, and increase of hardness was confirmed. The presence of Al-Si-C-O compound was detected by TEM analysis.

• Journal of the Korean Ceramic Society
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• v.26 no.5
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• pp.691-697
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• 1989

Fine TiO2 and BaTiO3 powders having spherical particles were synthesized by ultrasonic spray pyrolysis of alcoholic solution of metal alkoxide in an electric furnace heated at 400-90$0^{\circ}C$. Microstructure and composition of particles synthesized were observed by TEM and XRD respectively. Spectific surface area of powders synthesized was examined through BET specific surface area measurement. TEM observation revealed that the particle size did not change irrespective of pyrolysis temperature but decreased according to the increase of concentration and spherical particle was consisted of primary particles of about 0.02${\mu}{\textrm}{m}$. As for BaTiO3 powder, the ratio of Ti/Ba was 0.987 by EDX analysis.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.9-15
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• 2007

A comparative study of the structure and organization of the primary and secondary walls in different types of tropical plant waste fibers was carried out using transmission electron microscopy (TEM). The thickness of each layer was also measured using Image Analyzer. TEM micrographs haveconfirmed that cell wall structure of all six types of tropical plant waste fibers (empty fruit bunch, oil palm frond, oil palm trunk, coir, banana stem and pineapple leaf) has the same ultrastructure with wood fibre. The fibers consisted of middle lamella, primary and thick secondary wall with different thickness for different types of fibers. The secondary wall was differentiated into a $S_1$ layer, a unique multi-lamellae $S_2$ layer, and $S_3$ layer.

• Journal of Microbiology
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• v.44 no.1
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• pp.126-128
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• 2006

This study confirms that Taq DNA polymerase could be contaminated with the $blaTEM-1_a$ gene. It also proposes two different methods that could be used to overcome DNA contamination: (i) DNase I treatment prior to PCR amplification; and (ii) the use of a highly purified Taq DNA polymerase which was devoid of detectable contamination.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.18 no.2
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• pp.60-66
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• 2010

Normal Operations Safety Survey (NOSS), a methodology for capturing safety data during normal Air Traffic Control (ATC) operations. The NOSS methodology is based on the Threat and Error Management (TEM) framework, and is a safety management tool to monitor safety during normal aviation operations. Monitoring safety in normal operations is an essential activity within the safety management systems of Air Traffic Services (ATS) providing organizations, and NOSS is proposed as a suitable way to do this. This study, operating in the latter half of the year of 2010 in South Korea on NOSS was the understanding and to apply.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.3
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• pp.299-305
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• 1995

Visible photoluminescing (PL) silicon at room temperature has been prepared by a dry technique, that is, by spark processing, contrary to anodically etched porous silicon. PL peak maximum of photoluminescing spark processed Si was shifted to blue 520 nm. The stability of spark processed Si towards degradation upon UV radiation was found to be extremely high. Results from high resolution TEM, XRD and XPS studies suggest that spark processed silicon involves minute nanocrystalline (polycrystalline) particles which are imbedded in an amorphous matrix, preferably $SiO_2$.

• Journal of the Korean Ceramic Society
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• v.42 no.4
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• pp.287-291
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• 2005

Pop-in deformation phenomena in aluminum was studied. Whether a pop-in occurs or not depended on the surface polishing method. Pop-in did not occur in aluminum which was polished mechanically, while it occurred in aluminum which was polished electrically. When pop-in occurred, elastic deformation preceded. Pop-in mechanism based on dislocation activity was suggested. Suggested mechanism was consistent with the result of microstructure analysis by Focused Ion Beam polisher (FIB) and Transmission Electron Microscopy (TEM).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.7
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• pp.468-471
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• 2014

The effects of ZnO coating on the sensing properties of CNT:ZnO based gas sensors were studied for $H_2S$ gas. The nano ZnO sensing materials were grown by hydrothermal reaction method. CNT:ZnO was prepared by ball-mill method. The mole range of nano ZnO coating on CNT surface was from 0 to 10%. The CNT:ZnO gas sensors were fabricated by a screen printing method on alumina substrates. The structural and morphological properties of the CNT:ZnO sensing materials were investigated by XRD, EDS, SEM and TEM. The XRD patterns showed that CNT:ZnO powders with hexagonal structure were grown with (002) dominant peak. The diameter of CNT from TEM was about 28 nm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.6
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• pp.538-543
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• 2008

Nanostructured materials are attracting increased interest and application. Exciting perspectives may be offered by electrical insulation. Epoxy/Organoclay nanocomposites may find new and upgraded applications in the electrical industry, replacing conventional insulation to provide improved performances in electric power apparatus, e.g, high voltage motor/generator stator winding insulation, dry mold transformer, etc. In the paper work, the electrical and thermal properties of epoxy/organoclay nanocomposites materials were studied. The electrical insulation characteristics were analyzed through the permittivity characteristics. by analyzing the permittivity spectra, it was found that dielectric constant becomes smaller with increase frequency and becomes larger with increase temperature. This indicates restriction of molecular motion and strong bonds at the epoxy/organoclay nanocomposites. The morphology of nanocomposites obtained was examined using TEM and X-ray diffraction. It has been shown that the presence of polar groups leads to an increased gallery distance and partial exfoliation. Nevertheless, full exfoliation of clay platelets has not been achieved.