• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.875-879
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• 2008

A method for the depolymerization of polycarbonate waste by glycolysis using ethylene glycol without catalyst was explored in order to get the monomer bisphenol A (BPA). The effect of operation variables such as reaction time, reaction temperature, EG/PC weight ratio and the kinetic of glycolysis were studied. It was found that the polymerization reaction has two different activation energies depending on the reaction temperature. A drop in activation energy with temperature indicates that the reaction mechanism has shifted from one of a succession of elementary steps to another in the series. The maximum yield of BPA of 95.6% was achieved at reaction temperature $220^{\circ}C$ for 85min with EG/PC weight ratio 4.

• Journal of the Korean Institute of Gas
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• v.8 no.4 s.25
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• pp.23-29
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• 2004

This work carried out experiment to change characteristics of hydrate formation using various chemicals which are acetone, dimethylbutane, polyvinylalcohol, methanol and ethlyene glycol as additives in gas hydrate formation. Gas storage ability of formed hydrate with acetone, firnethylbuthane and polyvinylalcohol in gas hydrate formation increased higher than that obtained with pure water. Among them polyvinylalcohol showed best gas storage ability, so it is a more useful promoter Methanol and Ethylene gl?col in using additives showed the characteristics of inhibitor and methanol is lower gas storage ability than ethylene gl)rcol as a inhibitor in hydrate formation, so it is a more useful inhibitor. But, low concentration of methanol and ethylene glycol showed considerably higher gas storage ability of hydrate than that obtained with Pure water and showed the characteristics of promoter in gas hydrate formation.

• Polymer(Korea)
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• v.25 no.4
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• pp.528-535
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• 2001

Polyurethane specimens were mainly composed of polyol, MDI, silicone surfactant, and water. The effects of ethylene glycol on the cell size, forming magnification, cream time, gel time, take free time, final free rising height, and reactive temperature were investigated. The cyclopentane was used for PU foam as a physical blowing agent. The components were hand-mixed at about 5000 rpm within 4 seconds at room temperature. The mixtures with various ethylene glycol contents were foamed in the wood mold. When the index of isocyanate was fixed, as the amount of ethylene glycol increased, cell size and thermal conductivity were decreased by about 5.1% and 14%, respectively.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.2
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• pp.111-115
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• 2012

In this paper, the thermal conductivities of ethylene glycol. based ZnO nanofluids manufactured using the pulsed wire evaporation method are experimentally measured using the transient hot wire method at temperatures in the range of $10^{\circ}C$ to $50^{\circ}C$. For this purpose, ethylene glycol.based ZnO nanofluids with 1%, 3%, and 5.5% volume fractions were manufactured using the pulsed wire evaporation method. Transmission electron microscopy (TEM) was performed to investigate the suspension stability of the ethylene glycol.based ZnO nanofluids. Based on the experimental results, the thermal conductivities of ethylene-glycol-based ZnO nanofluids increase with increasing volume fractions of ZnO nanofluids. The maximum enhancement of the thermal conductivity is 26.5% for a volume fraction of 5.5% at $22^{\circ}C$. Finally, the experimental results are compared with conventional models such as the Maxwell and Hasselman & Johnson models.

• 월간산업보건
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• s.297
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• pp.30-34
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• 2013

• Proceedings of the Korean Fiber Society Conference
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• 1992.06b
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• pp.58-59
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• 1992

• Proceedings of the Korean Fiber Society Conference
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• 1992.06b
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• pp.104-105
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• 1992

• 대한생식의학회:학술대회논문집
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• 2005.06a
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• pp.107.2-108
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• 2005

• Journal of the Korean Solar Energy Society
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• v.22 no.4
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• pp.51-61
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• 2002

Analysis of thermodynamic design data of double effect solar absorption heat pump system for heating has been done to find the property of Libr-water + ethylene Glycol mixture for working fluid by computer simulation. Derived thermodynamic design data. enthalpy based coefficient of performance and flow ratio for possible combinations of operating temperature for water - LiBr and Ethylene Glycol mixture (H2O: CHO ratio 10:1 by mole) by computer simulation. The obtained results, COP and mass flow ratio of the water-lithium bromide-ethylene glycol system, are compared with data for the water-Libr pair solution.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.58-58
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• 2001