• Composites Research
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• v.34 no.3
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• pp.180-185
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• 2021

Due to the formation of random three dimensional network structure, which cause a lot of scattering of phonons, the thermal conductivity is low when the liquid crystalline epoxy is cured with amine-based curing agent. This problem is solved by using a cationic initiator that can make mesogen groups to be stacked structure. In this experiment, the thermal stability is compared by investigating the activation energy of isothermal decomposition through TGA of an epoxy using an amine-based curing agent and a cationic initiator. As a result, the energy of the activation of the epoxy using a cationic initiator is high. Compared with the previous experiments, the thermal stability is similar to the thermal conductivity.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.127-128
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• 2006

Nafion/basic polymer composite membranes were prepared to reduce the methanol crossover for the application of direct methanol fuel cell. The thermal and mechanical properties increased with increasing basic polymer contents due to the formation of complex via acid/basic interaction. The water uptake, proton conductivity, methanol permeability decreased with increasing basic polymer concentration by reduction of acidity associated with the formation of acid/base complex. The molecular effect on those properties was not considerable.

• Analytical Science and Technology
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• v.8 no.4
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• pp.821-827
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• 1995

Polychlorodibenzo-p-dioxins(PCDDs) have been prepared by microsacale pyrolysis of trichlorophenates. During the pyrolysis reaction, dechlorinated dibenzo-p-dioxins were also formed by the thermolysis of PCDDs. The dechlorination pathways of PCDDs were suggested in this reaction. The identification of these products was performed using capillary column gas chromatography-mass spectrometry.

• Journal of the Korean Vacuum Society
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• v.4 no.S2
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• pp.115-130
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• 1995

In order to produce Cu nanocrystallite in silicon wafer, the implantation technique was used. The samples of silicon (100) wafers were implanted by $Cu^+$ ions at 100 keV and with varying the doses at room temperature. Post-annealing was performed at $800^{\circ}C$ with Ar environment. To investigate the formation of Cu nanocrystallite with ion doses and growth process by thermal annealing, SIMS and HRTEM(high resolution transmission electron microscopy)spectra were studied.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.245-248
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• 1990

A series of compounds were synthesized that contain varying number of mesogenic units, 4-n-butylazobenzene moiety, attached to the central benzene ring through ester bond. These compounds were subjected to thermal analysis on a differential scanning calorimeter (DSC) and also on a polarizing microscope. It was found from this study that the presence of mesogenic units in a multi-mesogenic compound does not guarantee for the compound to become mesomorphic and that the linear molecular shape is conducive to form a liquid crystalline phase.

• 한국연소학회:학술대회논문집
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• 1998.10a
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• pp.155-164
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• 1998

Numerical analysis was performed with multicomponent transport properties and detailed reaction mechanisms for axisymetric 2-D CH4 jet diffusion, partial premixed, premixed flame. Calculations were carried out twice with C2-Full Mechanism including prompt NO reaction in addition to the above C2-Thermal NO Mechanism. The role of thermal NO mechanism and prompt NO mechanism on each flame's NO production is investigated by using the numerical result. The NOx production of each flame were evaluated Quantitatively in terms of the NOx emission index

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.339-342
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• 2014

Rotary kiln produces lime from limestone through thermal decomposition. Ring formation in kiln internal wall is known issue that decreases productivity. The cause of ring formation is temperature imbalance as flame leans toward upper wall. Therefore, burner nozzle geometry was changed to improve air-fuel mixing state which leads to prevention of ring formation. CFD simulation and experimental test were performed in this study to investigate the effect of air-fuel mixing on flame structure, temperature and $NO_X$ concentration. It is shown that combustion efficiency has been enhanced and $NO_X$ concentration has been decreased by using swirl flow for secondary combustion air. It's also shown that flame has been straightened by using straight flow for secondary combustion air.

• Journal of the Semiconductor & Display Technology
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• v.6 no.4
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• pp.5-9
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• 2007

Phase transition and dopant redistribution during silicidation of $CoSi_2$ thin films were characterized depending on their preparation methods. Our results indicated that cleanness of the substrate surface played an important role in the formation of the final phase. This effect was found to be reduced by addition of W resulting in the formation of $CoSi_2$. However, even in this case, the formation of the final phase was achieved at the cost of extra thermal energy, which induced rough interface between the substrate and the silicide film. As for the dopant redistribution, the deposition sequence of Co and Si on SiGe was observed to induce significant differences in the dopant profiles. It was found that co-deposition of Co and Si resulted in the least redistribution of dopants thus maintaining the original dopant profile.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.10
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• pp.814-820
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• 1991

TaSi$_2$ was formed by rapid thermal annealing(RTA) on BF$_2$ doped single crystalline silicon substrates. The formation and various properties of TaSi$_2$ have been investigated by using 4-point probe, HP414, XRD, and SEM. And the redistribution of boron with RTA has been observed by SIMS. Implanted boron was diffused out into the TaSi$_2$ for RTA temperature but did not significantly affect the formation temperature of TaSi$_2$. Also, the contact resistance for TaSi$_2$/p$^{+}$ region had a low value 22$\Omega$, at contact size of 0.9$\mu$m, and the native oxide formed on Si-substrates by BF$_2$ implantation retarded the formation of TaSi$_2$.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.166-170
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• 2001

Dopants implanted in silicon substrate affect the reaction between cobalt and silicon substrate. Phosphorous, unlike boron and arsenic, suppressing the reaction between cobalt and silicon induces CoSi formation during a low temperature thermal treatment instead of CoSi₂formation. The CoSi layer should move to the silicon substrate to fill the vacant volume that is generated in the silicon substrate due to the silicon out-diffusion into the cobalt/CoSi interface. The movement of CoSi at gate sidewall spacer region is suppressed by a cohesion between gate oxide and CoSi layers, resulting in a void formation at the gate sidewall spacer edge.