• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.35-42
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• 2014

The efforts to reduce carbon emission have been made in many aspects and in road, the study to develop the construction method which will replace asphalt and cement is also underway. But given the low cost and high performance offered by cement, among many solidification agents, it's difficult to seek the competent alternative. Polymeric material has been used in various ways for its advantages including lightweight and easy process for complex function and generates less carbon emission, and thus it would possibly be efficient if it replaces soil pavement using cement. This study, using three different types of organic polymeric solidification agents with different solidification principle, is intended to identify the difference in strength depending on curing method, natural dry or oven dry. Applicability of organic polymeric solidification agents to walkway and bike lane was investigated and as a result of unconfined strength test, all of them satisfied the minimum strength requirements of bike lane. Furthermore, strength characteristics of soil pavement depending on variation of water content was evaluated to identify the relationship, thereby appropriate curing method using organic polymeric solidification agent is proposed.

• Journal of Adhesion and Interface
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• v.19 no.2
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• pp.74-82
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• 2018

Many methods for cross-linking acrylic PSAs have been discussed previously. For high cross-linking density, epoxy functionalized monomer and methyl aziridines as cross-linking agents were used in this study. Additionally, photopolymerization using different UV doses was investigated to synthesize a binder because of its rapid productivity. FT-IR analysis, curing behaviours and adhesion performance were examined for the relationship between UV doses and temperature as curing conditions. According to the results, the gel fraction was over 50% even at $120^{\circ}C$ after UV curing at a dose of $800mJ/cm^2$. On the other hand, while gel fractions of all samples reached approximately 80% only at $180^{\circ}C$ in thermal curing for 1 hour, gel fractions of the samples after thermal curing for 3 hours increased rapidly above $120^{\circ}C$ regardless of UV doses and reached approximately 100% at $180^{\circ}C$. This means that the second cross-linking reaction, esterification, is mainly dependent on the curing temperature.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.571-574
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• 2000

When fresh concrete is exposed to low temperature, the concrete may suffer from the frost damage at early ages and the strength development may be delayed. To solve such problems of cold weather concreting admixtures called agent for enduring cold climate are developed to prevent the fresh concrete from being frozen at early ages. In this study, the experiments are carried out on several kinds of agent for enduring cold climate to present their performance. According to experimental results, most kinds of agent for enduring cold climate show the strength development in the range $-5^{\circ}C$ of curing temperature, it tends to be delayed at long term maturity without agents for enduring cold climate. while it gains high strength maturity when agents for enduring cold climate is applied.

• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.33-39
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• 1995

To accelerate the cure of phenolic resin adhesives for plywood, the complexation with melamine resin and the addition of cure-accelerating agents were discussed. The hot-pressing temperature and time of phenol resin could be decreased by complexation with melamine resin. but the wet glue-joints strength of phenol melamine resin was lower than that of ordinary phenol resin in case of plywood using spruce veneer at core layer. Among the tested cure-accelerating agents. the sodium carbonate showed the greatest effect on shortening gelation time of phenolic resin. In addition, in the manufacturing scale test, the hot-pressing time of phenol resin with the addition of 5 parts sodium carbonate could be shortened about 20% compared with ordinary phenol resin which had same glue-joints properties.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.309-312
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• 2005

Admixture compounds for shortening setting time and accelerating early strength development of EVA polymer powder-modified mortars were made by mixing various quick setting agents. As a result, the quick setting agents contribute to strength development of the mortars in the early curing age of 168h or less. In the viewpoint of early strength development of EVA polymer powder-modified mortars, an quick setting agent content of 20$\%$ is recommended. Early strength of EVA polymer powder-modified mortars expresses the excellent strength with 5$\%$, 10$\%$ of rates of polymer mixing. The rate of polymer mixing was able to be adjusted and flexural strength which is a predeterminded initial strength was also able to satisfy 3MPa(s).

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.576-577
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• 2003

I. Objectives This study investigated the dentin shear bond strength and the degree of conversion (DC) of currently used dentin bonding agents (DBAs) that were irradiated with a light emitting diode (LED) light curing unit (LCU) and a halogen LCU. II. Materials and methods The halogen LCU and the LED LCU used in this study were a VIP(Bisco, Schaumburg, IL, USA) and an Elipar Freelight(3M ESPE, St Paul, MN, USA) respectively. For the VIP, $400mW{\cdot}cm-2$ intensity mode was used to adjust to the intensity of the LED LCU. The DBAs used in this study were Scotchbond Multipurpose (3M ESPE), Single Bond (3M ESPE), One-step(Bisco), Clearfil SE Bond(Kuraray), and Adper Prompt(3M ESPE).(omitted)

• Proceedings of the KACD Conference
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• 2008.05a
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• pp.213-223
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• 2008

The objective of this study was to compare dentin shear bond strength (DSBS) of dentin bonding agents (DBAs) cured with a plasma arc (PAC) light curing unit (LCU) and those cured with a light emitting diode (LED) LCU. Optical properties were also analyzed for Elipar freelight 2 (3M ESPE); LED LCU, Apollo 95E (DMT Systems); PAC LCU and VIP Junior (Bisco); Halogen LCU. The DBAs used for DSBS test were Scotchbond Multipurpose (3M ESPE), Singlebond 2 (3M ESPE) and Clearfil SE Bond (Kuraray). After DSBS testing, fractured specimens were analyzed for failure modes with SEM. The total irradiance and irradiance between 450 nm and 490 nm of the LCUs were different. LED LCU showed narrow spectral distribution around its peak at 462 nm whereas PAC and Halogen LCU showed a broad spectrum. There were no significant differences in mean shear bond strength among different LCUs (P > 0.05) but were significant differences among different DBAs (P < 0.001).

• Restorative Dentistry and Endodontics
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• v.33 no.3
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• pp.213-223
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• 2008

The objective of this study was to compare dentin shear bond strength (DSBS) of dentin bonding agents (DBAs) cured with a plasma arc (PAC) light curing unit (LCU) and those cured with a light emitting diode (LED) LCU. Optical properties were also analyzed for Elipar freelight 2 (3M ESPE); LED LCU, Apollo 95E (DMT Systems); PAC LCU and VIP Junior (Bisco); Halogen LCU. The DBAs used for DSBS test were Scotchbond Multipurpose (3M ESPE), Singlebond 2 (3M ESPE) and Clearfil SE Bond (Kuraray). After DSBS testing, fractured specimens were analyzed for failure modes with SEM. The total irradiance and irradiance between 450 nm and 490 nm of the LCUs were different. LED LCU showed narrow spectral distribution around its peak at 462 nm whereas PAC and Halogen LCU showed a broad spectrum. There were no significant differences in mean shear bond strength among different LCUs (P > 0.05) but were significant differences among different DBAs (P < 0.001)

• Food Science and Preservation
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• v.23 no.5
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• pp.645-653
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• 2016

The objective of this study was to examine quality characteristics of a smoked duck marinated in natural curing agents containing extracts of pear by sugar, celery powder, and vitamin C. We evaluated the composition food additives residue and total plate count, chromaticity, sensory properties, total polyphenol contents, 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of general smoked duck (GSD) and natural smoked duck (NSD). The nitrite ion, antioxidant and sodium glutamate of NSD were not detected. The lightness, yellowness and redness of the two smoked duck decreased significantly as growing longer storage days. The total plate count (CFU/g) of coliform bacteria of two smoked duck were not grown. The sensory properties showed that NSD was higher than GSD in the aspect of taste, texture and overall preferences. The total polyphenol contents and DPPH radical scavenging effect of NSD were higher than those of GSD. These results suggested that it was possible to manufacture a smoked duck marinated in natural curing agents including extracts of pear by sugar, celery powder, and vitamin C for the improvement of safety and quality.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.2
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• pp.68-78
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• 2001

UV-curable resin has the properties of quick-drying, thigh productivity at low temperature, energy savint, space saving, solventless, non-polluting and low-stinking, and thus, UV-curing system has been widely used in the fields of printing inks, adhesives, paints and coating agents. This study has been executed to micro-patterning used UV-curable resin, The micro-patterning properties of this photoresist were investigated under irradiation of UV light low pressure mercury lamp. When the exposed photoresist film was developed by pure water developer, the resolution of this photoresist was about 50$\mu\textrm{m}$.