• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1046-1053
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• 2010

The objective of this study was to investigate the pyrolytic reaction characteristics of a mixed fuel of municipal solid wastes and low-grade anthracite. The reaction variables are pyrolysis condition of mixing ratio, reaction temperature, temperature increase rate. As a result, the optimum mixing ratio was 20 wt.% low-grade anthracite in MSW, which maintains for the low heating value over 3,500 kcal/kg on pyrolysis. The most high reaction velocity constant was shown at $700^{\circ}C$. Also, under the all experimental condition, the reaction velocity constant increased linearly as temperature rate increase, but pyrolysis has to be considered electric power cost and yield of char at lower temperature rate.

• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.104-108
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• 2001

Naphthalene derived mesophase pitch WP) was spun into short fibers by using melt-blown technology. The pitch fibers oxidative stabilization were carried out heating rates of $2^{\circ}C/min,\;5^{\circ}C/min\;and\; 10^{\circ}/min$. The heating rate was a key factor to maximate the capacity of the Li-ion secondary battery through controlling the morphology of the graphitized fiber. The diameters of the melt-blown fibers prepared were in the range of $4{\mu}m\~16{\mu}m$ with functions of air jet speed, air temperature and the temperature of the nozzle. The graphitized fibers of $10{\mu}m$ diameters showed various morphological structure with heating rate of the stabilization. Radial, radial-random and skin-core cross-sectional structure of the fibers were observed at the respective heating rate of $2^{\circ}C/min\;5^{\circ}C/min\;and\;10^{\circ}C/min$. Most crystalline structure of graphite was obtained from the fiber stabilized at heating rate of $10^{\circ}C/min$ exhibiting the best anode performance with 400 mAh/g of capacitance and $96.8\%$ of charge/discharge efficiency.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.135.2-135.2
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• 2007

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.109.2-109
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.264-264
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• 1999

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.04a
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• pp.55-56
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• 2005

• Korean Journal of Materials Research
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• v.5 no.3
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• pp.345-356
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• 1995

본 연구에서는 TiAl 금속간 화합물을 자전 고온 반응법을 이용하여 제조시 반응과정을 열시차 분석 방법으로 분석하였다. 합금 조성은 Ti-45at% Al, 53at%Al, 알루미늄 분말 크기, 승온 속도, 성형 밀도 등을 변화시켜 이들이 반응 과정에 미치는 영향을 관찰하였다. 분말이 미세할수록, 승온속도가 느릴수록, 성형 밀도가 낮을수록 반응 점화 온도 및 연소 온도가 감소하였으며, 고상 Ti와 고상 Al간의 반응정도가 증가하는 것이 관찰되었다. 고상 Ti와 고상 Al간의 반응에서 생성되는 것은 XRD 분석 결과 Ti$Al_{3}$상으로 확인되었다. 이에 비하여 반응 점화 온도가 알루미늄의 용융 온도보가 높을 경우에는 생성되는 상이 $Ti_{3}$Al, TiAl상으로 확인되었다. 이러한 상의 생성 원인에 대하여 확산 계수 및 알루미늄의 용해도등의 요인으로 설명하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.2
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• pp.191-196
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• 1999

Effects of agitation and heating rate on crystallinity, size distribution and mean size of $\alpha$-$SiO_2$powder prepared hydrothermally were investigated. $\alpha$-$SiO_2$crystalline powder, in mean particle size of 1~3.2 $\mu\textrm{m}$, was obtained at $350^{\circ}C$ using KOH as a mineralized for a 3 h reaction. Experimental results showed that particle size became smaller as the rate of agitation increased if it was introduced from the beginning of reaction, however, crystallinity was reduced at the low rate of agitation and it was became enhanced at above 150 r/min. Particle size became larger if agitation was introduced at any time during the reaction rather than introduced from the beginning of reaction. It was also found that particle size became smaller if heating rate was reduced, while the rate of agitation kept constant.

• Journal of the Korean Ceramic Society
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• v.42 no.1
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• pp.33-36
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• 2005

Effect of heating rate was studied on consolidation of the low-temperature-sinterable PMN-PT-BT powder by varying the heating rate from 5, 10, to $20^{circ}C/min$. Slow rate of $5^{circ}C/min$ showed more homogeneous microstructure than high rate of 10 or $20^{circ}C/min$ due to low PbO (m.p. $886^{circ}C$) evaporation at 850^{circ}C$. It showed sintered density of $7.93 g/cm^{3}$, room temperature dielectric constant of 15300, and dissipation factor of $0.92\%$.

• Elastomers and Composites
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• v.38 no.4
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• pp.326-333
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• 2003

Even though many studies have been reported about rubber vulcanization, it is still remained difficult to find a quantitative relationship between the final states of vulcanized rubber and initial formulation or processing conditions. Dynamic differential scanning calorimetry (DSC) method is known as a comparatively easy method to research for the rubber vulcanization in both experimental and analysis. In the present research, a study on the vulcanization reaction of NR/CB composites modified by isoprene(IR) and chloroprene(CR) rubbers is carried out using dynamic DSC method. Thermograms with several different heating rates were obtained and analyzed using the Kissinger method. Analysis showed that the vulcanization reaction was progressed through the first order reaction mechanism. In addition, the reaction temperature was severely influenced by the kinds or rubber modifiers, in this case, more influenced by CR than by IR. Those effects were clearly verified in the values of activation energy. Kinds of carbon blacks, however, could hardly influence on the reaction mechanism.