• JOURNAL OF ELECTRICAL WORLD
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• s.440
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• pp.12-14
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• 2013

• The Safety technology
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• no.91
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• pp.40-41
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• 2005

• 프린팅코리아
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• v.9 no.7
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• pp.105-105
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• 2010

• the MEAT Journal
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• s.1 fall
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• pp.54-55
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• 1987

• KOREAN POULTRY JOURNAL
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• v.53 no.3
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• pp.116-121
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• 2021

• Elastomers and Composites
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• v.46 no.4
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• pp.304-310
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• 2011

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using briged rac-$Et[Ind]_2ZrCl_2$ or unbriged $Cp_2ZrCl_2$ metallocene catalysts. Bridged rac-$Et[Ind]_2ZrCl_2$ catalyst showed relatively good results compared with unbridged one. When cocatalyst/catalyst molar ratio was 3000, catalytic activity indicated more than 8000(kg of polymer/$mol{\cdot}h$) which was very remarkable value. As a polymerization time increased, the weight-average molecular weight of the terpolymer gradually increased to some degree. In the case of a polymerization time of 50 minutes, the state of the terpolymer became amorphous. The range of the weight-average molecular weight and the densities of the terpolymer was 110,000~200,000 and $0.85{\sim}0.89g/cm^3$, respectively. The thermal properties and the structure of the terpolymer were also identified.

• Elastomers and Composites
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• v.48 no.4
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• pp.263-268
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• 2013

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using bridged rac-$Et[Ind]_2ZrCl_2$ metallocene catalysts. The effect of 1-hexene on the terpolymerization rate was evaluated. When cocatalyst/catalyst molar ratio was 3,000, catalytic activity indicated more than 8,000 which was very remarkable value. As polymerization time increased, the weight-average molecular weight of the terpolymer gradually increased to some degree. In case of a polymerization time of 50 minutes, the terpolymer became amorphous state. The molecular weight distribution and densities of the terpolymer were 110,000-200,000 and $0.85-0.89g/cm^3$, respectively. Thermal properties and structure of the terpolymer were also identified.

• Journal of the Korean Electrochemical Society
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• v.6 no.3
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• pp.178-182
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• 2003

The oxygen reduction and NiO dissolution behaviors in Li-Na-K three component carbonate melts have been investigated with various compositions through electrochemical and chemical ways. The oxygen reduction currents and NiO solubilities were measured at $650^{\circ}C$ and atmospheric condition in Li-Na-K =47.4-32.6-20, 60-20-20, 50-40-10, $40-40-20 mol\%$ carbonate melts. The oxygen reduction currents showed dependence on the composition, indicating oxygen solubility is a function of carbonate composition. At the composition of $ Li-Na-K=50-40-10 mol%$, a broader peak was observed, suggesting different oxygen reduction mechanism probably prevails in this composition. In contrast, insignificant differences of NiO solubility were obtained among the compositions.

• Elastomers and Composites
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• v.47 no.4
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• pp.329-335
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• 2012

In this study, we synthesized poly(ethylene-ter-high ${\alpha}$-olefin-ter-p-methylstyrene) using Zr metallocene catalyst/borate type cocatalyst system. Various effects of the high ${\alpha}$-olefin (1-hexene, 1-octene, 1-decene, and 1-dodecene) were observed. The structure and composition of the terpolymers were characterized using $^{13}C$ NMR and $^1H$ NMR. Catalytic activity, polymer yield, molecular weight and molecular weight distribution were analyzed according to the chain length of high ${\alpha}$-olefin. We determined morphology, crystallinity and thermal properties of the terpolymers.

• Communications of Mathematical Education
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• v.25 no.1
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• pp.147-166
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• 2011

In this paper, we listed and discussed the properties of the Pythagorean triples which 5 gifted 9th graders could draw in spreadsheets environments. And we also discussed their implications. In detail, in spreadsheets environments students could make the table of Pythagorean triples easily under several conditions of generate numbers of Pythagorean triples. And they could draw several properties of Pythagorean triples from the tables and could prove them. In spreadsheets environments it is easy to give students chances of generalization of the properties of Pythagorean triples which they had obtained from the concrete table of Pythagorean triples.