• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.204-210
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• 2004

Though the recycling rate of coal fly ash generated from domestic thermoelectric power plants is gradually increased, at present, the most amount of coal bottom ash is disposed by a landfill instead of recycling. Therefore, to reuse a coal bottom ash as high-value materials the synthesis of zeolite made from a coal bottom ash was investigated in this study. NaPl, hydroxy-sodalite and tobermorite were produced through the alkaline hydrothermal reaction of pulvelized bottom ash at various temperatures; 80, 120, $150^{\circ}C$, and the concentration of NaOH at the range from 1 to 5 M. Especially, NaPl with excellent cation exchange capability had a high crystallinity at ${\leq}2$ M NaOH and ${\leq}120^{\circ}C$.

• Journal of Environmental Science International
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• v.10 no.6
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• pp.451-459
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• 2001

Adsorption characteristics of triadimefon and diniconazole(pesticide) by natural zeolite($CLI_N$) and several synthetic zeolites were Investigated. The synthetic zeolites used En this study were as follows: Faujasite synthesized from coal fly ash($FAU_F$); Zeolite synthesized from the mixture of FAU and Na-Pl synthesized from the ratio of Cheju scoria 6 to coal fly ash 4 by weight($(FAU + Na-Pl)_{SF}$); waste fluid catalytic cracking catalyst($FCC_W$). The distribution coefficient, $K_D$ and Freundlich constant, $K_F$ decreased in the fellowing sequence : $FCC_W ＞ FAU_F ＞ (FAU + Na-Pl)_{SF} ＞CLI_N$ among the zeolites. The distribution coefficient and the adsorption capacity of $(FAU + Na-Pl)_{SF}$ for pesticides were 4.4 and 2.6 times higher for triamefon, and 2.0 and 2.4 times higher for diniconazole than those of $CLI_N$, respectively.

• Journal of the Korean Vacuum Society
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• v.7 no.1
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• pp.11-16
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• 1998

In this study, we prepared a Na$_2$Se/NH$_4$OH solution to investigate a passivation effect of Se on GaAs surface. X-ray photoelectron spectroscopy and photoluminescence (PL) were used to analyse the surface chemical bonding states and the optical properties of GaAs after Se-treatment and a successive exposure to air, respcetively. It was observed that all of the observed selenium bound with arsenic to form As-Se bond and showed only one oxidation state as -2. PL intensity of Se-passivated surface was larger than that of HCI-cleaned surface, and this means that the effective reduction of surface state density of GaAs was successfully obtained by this treatment. However the existence of partial oxide on the Se-passivated surface was seemed to be a major cause to the degradation of Se passivation effcet. PL intensity of Se-passivated surface also decreased according to air-exposure and converged to that of HCI-cleaned surface.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.167-175
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• 1992

This study was conducted for an efficient utilization of waste fly ash obtained from the power plant. Fly ash was used for synthesizing zeolite. Na-Pl zeolite could be easily synthesized from waste fly ash and showed the potential to remove heavy metal ions. The synthetic zeolite showed good adsorption property for heavy metal much better than raw fly ash and natural zeolites. Na-Pl exhibited the high adsorption efficiency with a maximum value of 260 Pb mg/g and strong affinity for Pb2+ ion. The metal ion selectivity of Na-Pl was determined in a decreasing order : $Pb^{2+}$>$Cd^{2+}$>$Cu^{2+}$+>$Zn^{2+}$>$Fe^{3+}$

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.7-10
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• 2001

Adsorption of the pesticides (phosphamidon, fenitrothion, triadimefon and diniconazole) in natural zeolite (CL $I_{N}$) and several synthetic zeolites was incestigated. The pesticides were not adsorbed on zeolites (Na-Pl, SOD, ANA, JBW and CAN) synthesized from Jeju scoria. The distribution coefficient ( $K_{D}$) and the Freundlich constant ( $K_{F}$) decreased in the following sequences. FC $C_{W}$ (waste catalytic cracking catalyst)>FA $U_{F}$ (FAU Synthesized from coal fly ash)>(FAU+Na-Pl)$_{SF}$ (the mixture of FAU and Na-Pl synthesized from the ratio of Jeju scoria 6 to coal fly ash 4 by weight)>CL $I_{N}$ among the zeolites; diniconazole>fenitrothion> triadimefon>phosphamidon. As the temperature was increased, the amount of pesticide adsorbed per unit mass of zeolite increased for FC $C_{W}$, FA $U_{F}$ and (FAU+Na-Pl)$_{SF}$ but it decreased for CL $I_{N}$, for all the pesticides used in this study. It was independent of pH for phosphamidon, fenitrothion and triadimefon, but decresed as pH was increased for all the zeolites used in this study.y.udy.y.y.y.y.y.y.

• Proceedings of the Safety Management and Science Conference
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• 2007.11a
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• pp.181-191
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• 2007

Logistics creates a boom in accordance with the recent new technique's development along with the recent RFID/USN of ubiquitous computing technique. The wave of 4PL(Fourth Party Logistics) that added the strategic consulting based on new IT techniques to logistics outsourcing through existing 3PL service with is a great issue. Moreover, the customer enterprises which contained manufacturers and distributors need the one stop service, therefore a method for effectively dealing with global logistics' environment changes is needed. Above all, a development of the 4PL system with RFID is very urgent. We developed the RFID u-4PL system progressed more than the present system, in which we applied many international standards. Finally, we constructed the web service based on Web 2.0 because of important condition of 4PL.

• Journal of the Korea Safety Management & Science
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• v.9 no.5
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• pp.87-95
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• 2007

Logistics creates a boom in accordance with the recent new technique's development along with the recent RFID/USN of ubiquitous computing technique. The wave of 4PL(Fourth Party Logistics) that added the strategic consulting based on new IT techniques to logistics outsourcing through existing 3PL service with is a great issue. Moreover, the customer enterprises which contained manufacturers and distributors need the one stop service, therefore a method for effectively dealing with global logistics' environment changes is needed. Above all, a development of the 4PL system with RFID is very urgent. We developed the RFID u-4PL system progressed more than the present system, in which we applied many international standards. Finally, we constructed the web service based on Web 2.0 because of important condition of 4PL.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.579-582
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• 2008

The wave of 4PL added to strategic consulting based on new IT techniques, for example RFID, with logistics outsourcing through existing 3PL service is a great issue. It is also worthy of notice that EPCglobal network strengthen the role of 4PL. In conclusion, the 4PL system based on EPCglobal network will result in a good success, so it will raise a prestige of air cargo in Korea to a higher position. This study deals with the new logistics system, air cargo logistics system based on u-4PL system, RFID and EPCglobal network, that will bring many advantages.

• The Monthly Technology and Standards
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• s.9
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• pp.25-34
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• 2002

• The Monthly Technology and Standards
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• s.8
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• pp.16-28
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• 2002