• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.77-80
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• 1995

Enhancing the electrical conductivity of the ultrathin organic films using Langmuir-Blodget technique is important step for the developement of molecular electronic device. The Octadecylviologen-TCNQ was synthesized with Octadecylviologen-Bromide an Lithium TCNQ Sine Octadecylviologen-TCNQ has two TCNQ snion radicals, the conductivity of LB film is expected to increase. The $\pi$-A isotherm showed that the limiting area was 150${\AA}$$\^$2/ molecule and the silid-like transition surface pressure was 25 mN/m. The electronic transition of the TNCNQ anion radical was observed at 400 nm. Intermolecular charge transfer absorption was observed at 600nm and 850~1050 nm which ay resulted from the TCNQ anion radical dimer formation. The electrical conductivity of the viologen -TCNQ LB film was 10$\^$-6/cm This values was 100 times higher than that of the quinolinium-TCNQ and pyridinium-TCNQ LB films.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.334-337
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• 2002

The drinking water industry faces a growing number of difficultiesin the treatment of groundwater for drinking water production. Groundwater sources are frequently contaminated with nitrates and phosphates due to usage of chemical fertilizer In this study, feasibility of micellar enhanced ultrafiltation (MEUF) was investigated to remediate groundwater contaminated with nitrate and phosphate. Ultrafiltration membrane was cellulose acetate with molecular weight cut off (MWCO) 10,000 and celtyl pyridinium chloride (CPC) was used to form pollutant-micelle complex with nitrate and phosphate. The results show that nitrate and phosphate rejections are satisfactory. The removal efficiency of nitrate and phosphate show 80% and 84% in single pollutant system, respectively with 3 molar ratio of CPC to pollutants. In the multi-pollutant systems, the removalefficiency increased to 90 % and 89 % for nitrate and phosphate, respectively, The presence of nitrate in the solutions did not affect the removal of phosphate and that of phosphate did not affect the removal of nitrate. The concentration of CPC in the permeate and removal efficiency of CPC was a function of the concentration of CPC in the feed solutions.

• Journal of the Korean Chemical Society
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• v.25 no.3
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• pp.177-182
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• 1981

Benzoylpyridinium and lutidinium salts containing$ [MoO(NCS)_5]^{2-}$ have been synthesized. The complexes have been characterized by spectroscopic, magnetic susceptibility and conductivity studies. Benzoylpyridinium and lutidinium oxopentaisothiocyanatomolybdates(Ⅴ) arise from d-d and charge transfer transitions. The magnetic moments of the complexes are close to the spin-only values. The complex anions are mononuclear containing N-bonded $NCS^-$ ligand.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.412-422
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• 2002

The use of biochemical markers of bone turnover may be particular interest in the investigation of bone disorders with osteoporosis. Serum osteocalcin(OC), total alkaline phosphatase and procollagen C, reflecting bone formation, and urinary pyridinium cross-links excretion, reflecting bone reabsorption have been measured in hyperthyroidism, postmenopause women, after testosterone supplementation, androgen, testosterone and estrogen deficiency, bone mineral density degree, age duration. Bone marks which is reflect to metabolic bone disorders are biochemical indices method to measure enzyme activity about bone formation, bone absorption and bone components in blood or urine. Bone metabolism biochemical marks are correlated with osteophorotic agents and also represent significantly different between bone mineral density and bone biochemical marks. Therefore if we develope and use bone metabolism marks which have higher sensitivity and specificity in bone formation and bone absorption, I think that these bone biochemical marks can have utility in the clinical application to predict osteoporosis risk group, bone loss, bone fracture and response degree to treatment of osteoporosis risk groups.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.414-418
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• 1985

A general synthesis of ${\alpha},\{\beta}$-unsaturated carbonyl compounds has been developed by oxidation of t-allylic alcohols. In simpler system, pyridinium chlorochromate oxidation affords the functionality transposed carbonyls in excellent yields, making the reaction a useful and versatile synthetic method.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.1-6
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• 1998

To change permselectivity between anions through the anion exchange membrane in electrodialysis, the various modified anion exchange membranes were prepared: highly crosslinked anion exchange membranes, anion exchange membranes having benzyl trialkylammonium groups with different carbon number of alkyl chain as anion exchange groups and anion exchange membranes having pyridinium groups with a hydrophilic or hydrophobic substituent at a different position as anion exchange groups. It became clear from the evaluation of these membranes that the degree of the hydrophilicity of the anion exchange membranes greatly affects the permselectivity between two artions. To increase the hydrophiticity of the anion exchange membranes further, electrodialysis was carried out in the presence of ethylene glycols and the permeation of strongly hydrated anions increased and that of less-hydrated anions decreased. It became clear that the change in the permselectivity between two artions is due to the change in the affinity of anions to the membranes, not the change in mobility ratio of the anions in the membranes phase.

• Journal of the Korean Chemical Society
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• v.26 no.2
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• pp.73-80
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• 1982

The pyridine and 3,5-lutidine complexes of quinquevalent molybdenum have been prepared. The infrared, electronic and reflectance spectra and magnetic susceptibility data of the complexes are reported. It is found that the binuclear complexes contain the di-${\mu}$-oxo-dimolybdenum(V) group, $MoO_2Mo$, and the possible structures are proposed on the basis of elemental analysis and physical measurements.

• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1425-1446
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• 2002

An efficient procedure for the synthesis of 6,7-dichloro-5,8-phthalazinedione (4) was developed in 49% overall yield via chloroxidation of 5,8-diaminophthalazine (8). And a series of its derivatives, 7-pyridinium-5,8-phthalazinedione-6-oxide (9), 6-chloro-7-phenylamino-5,8-phthalazinedione (10), 6,6-dimethoxy-6H-2,3,6b,11-tetraazabenzo[a]fluoren-5-one (11a), and 6,6-diethoxy-6H-2,3,6b,11-tetraazabenzo[a]fluoren-5-one (11b) have been synthesized.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.487-490
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• 1996

The 13-hydroxyberbine(1), derived from berberinephenolbetaine, has been derivatized to furnish a variety of compounds such as 13-oxoberbine(2), 13-thioberbine(3), 13-chloroberbi ne(4), 13-(2-methylaziridine)berbine(5) and 13-carbolactoneberbine(6). Antitumor activity of these compounds was tested.

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1392-1396
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• 2004

The micellization of dodecylpyridinum chloride (DPC) assembled on aqueous gold nanoparticles has been studied as a function of concentration using Surface-Enhanced Raman Scattering (SERS). At the low concentration, the strong SERS band of the benzene ring moiety was observed at 1025 $cm^{-1}$, and assigned to “trigonal ring breathing”. According to high concentration of DPC, a new strong band was also appeared at 1012 $cm^{-1}$, which was assigned to “totally symmetry ring breathing”. The difference of two spectra seems to ascribe to the geometry of polar head group, i.e., pyridinium cation. These geometry exist flat-down at low concentration, whereas standing-up or tilted geometry at high concentration. The critical micelle concentration (CMC) was first obtained from the ratio of intensities of the two bands related to the benzene ring moiety by vibrational spectroscopy, and was about 28 mM. After the CMC, the benzene ring moiety in the micelle state was more restricted than in monomer state because there is no more change of intensities at 1012 $cm^{-1}$. In addition, the size of gold-assembled micelle was estimated using light scattering and it was about 328.3 nm.