• Proceedings of the Membrane Society of Korea Conference
• /
• 2003.05a
• /
• pp.110-113
• /
• 2003

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.3 no.1
• /
• pp.24-31
• /
• 1998

The separation and concentration of L-phenylalanine (L-Phe) using a supported liquid membrane (SLM) is investigated. A cation complex agent, di-2-ethylhexyl phosphoric acid (D2EHPA), is used as a carrier in the SLM with n-Heptane as a solvent. The reaction order and equilibrium constant in the formation reaction of L-phe-carrier complex are obtained from the extraction experiment. A mathematical model for a carrier mediated counter transport process is proposed to estimate the diffusion coefficient of L-phe-carrier complexly in the liquid membrant. Permeation experiments of L-phe using a SLM are performed under various operating conditions and optimum conditions for the transport of L-phe are obtained. Concentration of L-phe in the strip phase against its concentration is observed. Transport rate of glucose through liquid membrane is less than that of L-phe in the competitive transport of L-phe and glucose. And the existence of glucose reduced the transport rate of L-phe. The performance of separation with continuous strip phase is increased due to the dilution effect in the strip phase.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.625-627
• /
• 2007

We demonstrated high power efficiency and long lifetime in organic light-emitting diode (OLED) using new electron transport materials (ETMs). Electroluminescent device with these ETMs showed lower driving voltage than that with $Alq_3$. The device lifetime with a new ETM was 2 times longer than that with $Alq_3$.

• Bulletin of the Korean Chemical Society
• /
• v.17 no.12
• /
• pp.1109-1111
• /
• 1996

The Podand Ⅰ (Figure 1) has been studied as cation carrier in a bulk liquid membrane system. Ag+ and some other transition metal ions (M2+=Cu, Ni, Co, Zn, and Cd) have been transported using the podand as carrier in a bulk liquid membrane system. Studies on the transport of equimolar mixtures of two or three competing components have also been carried out with the same system. Ag+ exhibited a higher transport rate than the other M2+ in the competitive experiments. Ligand structure and the equilibrium constant for complex formation are important parameters in the transport of the metal ions.

• Journal of the Korean Chemical Society
• /
• v.58 no.5
• /
• pp.500-503
• /
• 2014

• Journal of the Korean Society of Safety
• /
• v.39 no.3
• /
• pp.20-26
• /
• 2024

The Chemical Substances Control Act of South Korea mandates submission of transportation plans containing information on the transportation of hazardous chemicals, with over 600,000 submissions recorded annually. In this study, big data analysis was performed on 2,506,985 transportation plans to identify trends and assess their correlation with chemical transportation accidents. The analysis confirmed that despite NaOH accounting for 20.7% of transportation plans, HCl constitutes 40% of chemical transportation accidents, which indicates a correlation of these accidents with the chemical properties of hazardous substances rather than with the number of submitted transportation plans. Furthermore, chemical transportation accidents show a higher probability of occurrence in the 6-8 am and 6-8 pm windows, which is in agreement with higher incidence and fatality rates. The departure points of transportation plans are closely related to the characteristics of local chemical industrial complexes such as Ulsan, Yeosu, and Gunsan, whereas the arrival points are closely related to Pyeongtaek, Hwaseong, and Icheon, which are the locations of semiconductor industries. Ultimately, achievement of safety by consideration of characteristics of transported chemicals, enhancement of driver concentration during specific times, and implementation of preventive measures tailored to local government characteristics are strategies anticipated to contribute to a reduction in chemical transportation accidents.

• Journal of the Society of Disaster Information
• /
• v.14 no.1
• /
• pp.59-64
• /
• 2018

In the trend of increasing awareness of chemical accidents, hazardous chemical transport vehicle accidents are occurring every year. In this study, we analyzed improvement of accident prevention and countermeasures through statistical analysis of hazardous chemical transport vehicle accidents. A total of 383 chemical accidents between January 2014 and December 2017 were analyzed. During this period, number of transportation accidents was 83 cases, accounting for 21.67% of total chemical accidents. In the current system, despite the direct handling of hazardous chemical, it is out of regulation of damage prediction unlike the workplace. In order to effectively respond to actual accident, information on damage prediction is required and should be shared with related ministry. And it should be developed to real-time monitoring of hazardous chemical transport vehicle through integrated control tower.

• Macromolecular Research
• /
• v.17 no.2
• /
• pp.104-109
• /
• 2009

Solid-state facilitated, olefin transport membranes were prepared by complexation of poly(styrene-b-iso-prene-b-styrene) (SIS) block copolymer and silver salt. Facilitated olefin transport was not observed up to a silver mole fraction of 0.14, representing a threshold concentration, above which transport increased almost linearly with increasing silver salt concentration. This was because firstly the silver ions were selectively coordinated with the C=C bonds of PI blocks up to a silver mole fraction of 0.20, and secondly the coordinative interaction of the silver ions with the aliphatic C=C bond was stronger than that with the aromatic C=C bond, as confirmed by FT-Raman spectroscopy. Small angle X-ray scattering (SAXS) analysis showed that the cylindrical morphology of the neat SIS block copolymer was changed to a disordered structure at low silver concentrations ($0.01{\sim}0.02$). However, at intermediate silver concentrations ($0.15{\sim}0.20$), disordered-ordered structural changes occurred and finally returned to a disordered structure again at higher silver concentrations (>0.33). These results demonstrated that the facilitated olefin transport of SIS/silver salt complex membrancs was significantly affected by their coordinative interactions and nano-structural morphology.

• Journal of the Korean Chemical Society
• /
• v.38 no.2
• /
• pp.129-135
• /
• 1994

Acyclic polyether dicarboxylic acid have been studied as metal cation carriers in a bulk liquid membrane system. The proton-ionizable ligands feature allows the coupling of a cation transport to reverse proton transport. This feature offers promise for the effective separation and concentration of metal cations with the metal cation transport being driven by a pH gradient. Metal cation transport increased regularly with increasing hydroxide($H^-$) concentration of source phase and with proton($H^+$) concentration of receiving phase. Competitive transport by the acyclic polyether dicarboxylic acids is selective for calcium ion over other alkaline-earth cations.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.6
• /
• pp.930-934
• /
• 2005

A chloroform membrane system containing a given mixture of benzylaza-12-crown-4 and oleic acid is introduced for the selective and efficient transport of $Pb^{2+}$ ion. The transport was capable of moving metal ions ‘up-hill’. In the presence of ${S_2O_3}^{2-}$ion as a suitable metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is (95.0 ${\pm}$ 1.7)%. The selectivity and efficiency of lead transport from aqueous solution containing $Tl^+,\;Ag^+,\;Mg^{2+},\;Ca^{2+},\;Co^{2+},$ $Ni^{2+},\;Cu^{2+},\;Zn^{2+},\;Hg^{2+}$ and $Cd^{2+}$were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of $Ag^+\;and\;Cu^{2+}$ were diminished drastically.