• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.562-567
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• 2007

The stereoselective synthesis of chiral terminal epoxide is of immense academic and industrial interest due to their use as versatile starting materials as well as chiral intermediates. In this study, new polymeric chiral Co(salen) complexes bearing tallium (III)chloride and iron (III)chloride (ferric chloride) have been synthesized and characterized. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of various terminal epoxides using water and phenol derivatives as nucleophiles. The easily prepared polymeric complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ and phenol nucleophiles, providing enantiomerically enriched terminal epoxides (> 98% ee). The system described in this work is very efficient for the synthesis of chiral epoxide, 1,2-diol and ${\alpha}$-aryloxy alcohol intermediates.

• Resources Recycling
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• v.2 no.2
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• pp.1-8
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• 1993

This study was carried out in order to define the effective collectors and the opitimum conditions for the removal of iron ion in waste water by flotation method. The results obtained in this study are summarized as follows. Fe(II) and Fe(III) were removed effectively at pH7 and 6 respectively by using sodium lauryl sulfate, an anionic collector. The anionic collector, aeropromotor 845, removed both Fe(II) and Fe(III) effectively in pH ranges of from 5 to 9. The cationic collector, trimetyl dodecyl ammonium chloride, removed both Fe(II) and Fe(III) effectively in pH ranges from 10 to 11 and from 4 to 10, respectively. Therefore, Fe(II) and Fe(III) could be effectively removed by forming the iron hydroxide precipitates by simple pH adjustment of the solutions above precipitation point of ferrous and ferric ion by flotation method. Then, the effective pH regulator and collector were NaOH and $Na_2CO_3$,aeropromotor 845 and trimetyl dodecyl ammonium chloride, respectively.

• Corrosion Science and Technology
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• v.5 no.2
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• pp.39-44
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• 2006

The dissolution amount of Zn plate was $0.058mg/cm^2$ in the non-magnetically treated solution, and was $0.059mg/cm^2$ in the magnetically treated solution after 24 hours of immersion. The magnetic treatment had no effect to corrosion of Zn plate as pH on surface was not recognized the difference. The addition of Zn(II) ion in the solution was prepared to the effects of corrosion and dissolution of Fe. The regularity was not obtained the effect of the magnetic treatment on the dissolution of Fe plate.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.59-64
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• 2004

This study was carried out to investigate influencing factors of bisphenol A(BPA) removal characteristic in conventional water treatment systems to be connected with coagulation, sedimentation, filtration and disinfection. The result are summarized as follows; In BPA removal, optimal doses of PAC, alum, ferric chloride were 7.5 mg Al/L, 10.0 mg AI/L, 15.0 mg Fek. PAC was most effective coagulant to remove BPA. In coagulation process, BPA removal efficiency were increased about 2％ by adjusting pH of raw water as 6. At temperature rise 1$0^{\circ}C$, BPA removal efficiency were increased 0.94％. but BPA removal efficiency in sand filtration process were under 1 ％ie, so that BPA was almost not removed. At free chlorine dose 1, 2 mg/L, the reaction rate constant k in the BPA removal have been calculated to be 0.397, 0.953 min$^{-1}$ . At free chlorine dose 1, 2 mg/1-, degradation reaction of BPA was completed during 10 min and BFA removal efficiencies were 97.66, 99.99％ at this time.

• Journal of the Korean institute of surface engineering
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• v.29 no.1
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• pp.60-72
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• 1996

A photoetching process is widely used for small and high precision parts in machinery, electronic and semi-conductor industries. One of the high precision parts, grid is very important part of digitron which use electron display, and it is fabricated by only photoetching process because of high precision. In this study, to develop high precision digitron grid, characteristics of etching solution were investigated with electrochemical test, that was potentiodynamic test and immersion test in the ferric chloride solution and added some additives. Based on the electrochemical etching test, grid was fabricated by continuous photoetching process at various etching condition. From the result of measured line width and etching depth under-cut and etching factor were calculated. For the fabrication of 25$\mu\textrm{m}$ line width, optimal etching condition was etching temperature 40~$45^{\circ}C$, spray pressure 1.5kg/$\textrm{cm}^2$ and etching time 3~4min.

• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.61-65
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• 2005

The oxidative transformation of triclosan with laccase from Trametes versicolor was conducted in a closed, temperature controlled system containing phosphate buffer for pH control. The optimum pH for triclosan transformation showed about 5. Despite the observation that elevated temperatures tended to inactivate the enzyme, increased transformation of triclosan was observed up to $50^{\circ}C$. Of the mediators studied, ABTS was most successful at enhancing triclosan transformation. About 80% of the toxicity of the initial mixture was reduced after the enzymatic treatment. In the presence of 1.0 mM of anions such as sulfite, sulfide, and cyanide, triclosan transformation was greatly inhibited. Chloride and fluoride ions exhibited inhibition of triclosan transformation at 25 mM. Ferric ion substantially inhibited triclosan transformation at 1.0 mM.

• Fibers and Polymers
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• v.1 no.1
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• pp.25-31
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• 2000

Poly(3-hexyl thiophene)(P3HT) and poly(3-dodecyl thiophene)(P3DT) were polymerized by oxidative coupling with ferric chloride. The P3HT light-emitting device emitted red light and it could be observable in the ordinary indoor light. The device had the turn-on electric field of about 3$\times$$10^7$ V/m. The maximum electroluminescene (EL) intensity was obtained when the thickness of polymer layer was about 130 nm in IT0/P3HT/Al device. The maximum external quantum yield was 0.002%. The maximum luminance was 21 cd/$m^2$. The EL intensity decreases with increasing the crystallinity of the polymer layer. By using the oriented poly(3-alkyl thiophene)(PAT) layer as an electroluminescent layer in the ITO/polymer/Al light-emitting devices, the polarized EL light emission was observed. The EL intensity ratio of parallel to perpendicular direction to the stretch direction for P3HT was about 1.40.

• BMB Reports
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• v.41 no.9
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• pp.657-663
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• 2008

The present study was undertaken to investigate the protective role of taurine (2-aminoethanesulfonic acid) against cadmium (Cd) induced oxidative stress in murine erythrocytes. Cadmium chloride ($CdCl_2$) was chosen as the source of Cd. Experimental animals were treated with either $CdCl_2$ alone or taurine, followed by Cd exposure. Cd intoxication reduced hemoglobin content and the intracellular Ferric Reducing/Antioxidant Power of erythrocytes, along with the activities of antioxidant enzymes, glutathione content, and total thiols. Conversely, intracellular Cd content, lipid peroxidation, protein carbonylation, and glutathione disulphides were significantly enhanced in these cells. Treatment with taurine before Cd intoxication prevented the toxin-induced oxidative impairments in the erythrocytes of the experimental animals. Overall, the results suggest that Cd could cause oxidative damage in murine erythrocytes and that taurine may play a protective role in reducing the toxic effects of this particular metal.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1391-1396
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• 2013

The photocontrolled reduction of silver nitrate to silver (Ag) nanoparticles on honeycomb-patterned poly(N-vinylcarbazole) (PVK)-cellulose triacetate (CTA) composite thin films was studied. The composites were prepared via the oxidative polymerization of N-vinylcarbazole with ferric chloride using different CTA concentrations. A honeycomb-patterned film was fabricated by casting the composite solution under humid conditions. Ag particles with a homogeneous distribution were produced by the composite film in a moderate CTA concentration, whereas aggregated Ag was obtained from the pure PVK film.

• Macromolecular Research
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• v.17 no.8
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• pp.609-615
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• 2009

Two types of nano composite were obtained by in situ chemical method in polyaniline (PANI)/dodecyl-benzenesulfonic acid (DBSA) system depending on the use of either ammonium persulfate (APS) or ferric chloride ($FeCl_3$) as the oxidant. In order to study the difference of the two composites in the surface characteristics, thermal stability, and electric properties, the composite films were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and temperature dependent DC electrical conductivity. The results revealed a large difference in the surface morphology, thermal stability, and the microstructure properties between the two composites, and these differences were considered responsible for the molecular order and conductivity.