• Korean Journal of Veterinary Service
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• v.25 no.4
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• pp.371-376
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• 2002

To determine the effect of picolinic acid on NOㆍ production, murine macrophages were incubated with either medium, various concentrations of picolinic acid, or IFN-${\gamma}$ plus picolinic acid for 48 hr. Picolinic acid does not induce NOㆍ production by itself, it acted synergistically with INF-${\gamma}$ for the induction of reactive nitrogen intermediate production in murine macrophages. Thymidine incorporation appeared to be reciprocally related to nitrite levels, suggesting that IFN-${\gamma}$ plus picolinic acid induced NOㆍ synthesis exerted antiproliferative effects.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.202-205
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• 2005

The effects of ligands on reactivity under GoAgg oxidation system have been studied. Picolinic acid containing carboxylic acid showed the most excellent activity among various ligands. Also, Picolinic acid of ortho position carboxylic group in pyridine ring largely increased reaction rates in the GoAgg oxidation systems. From these results, we proposed the new mechanism on the GoAgg oxidation using ligands having carboxylic group at ortho position.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.3
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• pp.192-197
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• 2016

A novel heteroleptic ruthenium(II) complex bearing a 4-picolinic acid unit as anchoring ligands (trans-dithiocyanato bis(4-picolinic acid)ruthenium(II) (trans-H1)) was synthesized and its chemical structure was identified by $^1H$-NMR, FT-IR and mass spectroscopy. The optical, thermal, electrochemical and dye adsorption properties of trans-H1 dye were investigated and compared with those of the gold standard ruthenium complex, Ru(4,4'-dicarboxy-2,2'-bipyridine)$_2cis(NCS)_2$ (N3). DSSCs based on trans-H1 dyes were examined under the illumination of AM 1.5 G, $100mWcm^{-2}$ and exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.46 V, a short-circuit current ($J_{SC}$) of $4.10mA{\cdot}cm^{-2}$, a fill factor (FF) of 60.4%, and a conversion efficiency (PCE) of 1.14%.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1331-1332
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• 2002

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.114-114
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• 2001

Since hypoxia-inducible factor-lalpha (HIF-lalpha) and the arylhydrocarbon receptor (AhR) shared the AhR nuclear translocator (Arnt) for hypoxia- and AhR-mediated signaling, respectively, it was possible to establish the hypothesis that hypoxia could regulate Cyplal expression. In order to understand the mechanism of Cyplal gene expression, we demonstrated here that hypoxic agents such as cobalt chloride, desferrioxarnine, and picolinic acid reduced the TCDD induced Cyplal promoter activity based on the determination of luciferase activity in Hepa I cells transfected with pmCypla1-Luc. Also cobalt chloride inhibited the TCDD stimulated Cyplal mRNA level as well as EROD activities in both Hepa I and MCF-7 cells. Hypoxic agents such as cobalt chloride, picolinic acid, and desferrioxamine showed inhibition of luciferase activity that was induced by lnM TCDD treatment with dose dependent manner. Concomitant treatment of 150${\mu}$M ferrous sulfate with 1∼100${\mu}$M desferrioxarnine or 1∼100${\mu}$M picolinic acid recovered from the hypoxic agents-inhibited luciferase activity that was stimulated by TCDD. Reciprocally, the hypoxic agents down regulated TCDD induced Cyplal mRNA level and CYP1A1 enzyme activity in Hepa I cells.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.4
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• pp.219-227
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• 2009

The effect of organic acids on the adsorption of U(VI) onto oxide surfaces ($TiO_2)$(anatase), $SiO_2$(amorphous) and $Al_2O_3$(amorphous)) has been investigated. Two different organic acids, salicylic and picolinic acids, were used. Changes of adsorption ratio of U(VI), which depend on the existence of organic acids in a sample, were measured as a function of pH. Quantities of adsorbed organic acids, which depend on the existence of U(VI) in a sample, were also measured as a function of pH. It is confirmed that the soluble complex formation of U(VI) with organic acids can deteriorate the adsorption of U(VI) onto $TiO_2$ surface. It is noteworthy that salicylic acid does not affect the adsorption of U(VI) onto $SiO_2$ surface, however, picolinic acid enhances the adsorption of U(VI) onto $SiO_2$ surface. The latter effect can be understood by considering the formation of a ternary surface complex on $SiO_2$ surface, which was confirmed by the co-adsorption of picolinic acid with U(VI) and the change in a fluorescence spectra of U(VI) on surface, In the case of $Al_2O_3$, organic acids themselves were largely adsorbed onto a surface without deteriorating the adsorption of U(VI). This would support the possibility of a ternary surface complex formation on the $Al_2O_3$ surface, and an additional spectroscopic study is required.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.929-936
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• 1995

LOMI 제염제의 전기화학적 제조공정 중 전하운반체의 역할 및 V$^{3+}$ 이온의 침전현상을 방지하기 위하여 첨가되는 과량의 formic acid 는 제염제 제조시에는 중요한 역할을 하지만 제염 폐기물의 양을 증가시키는 요인이 되기도 한다. EPRI 공정에서는 formate : V 의 비율(FVR)이 10:1 인 조건에서 V$^{2+}$-formate 를 제조한 후 음이온 교환 수지를 이용하여 과량의 formate 를 제거하는 공정을 사용한다. 이러한 방법으로 줄일 수 있는 FVR의 한계가 약 2.5 : 1 이다. 본 연구에서는 제염제 중 formate 의 양을 더욱 줄일 수 있는 방법으로써 V$^{2+}$-formate 제조시 용액 중에 picolinic acid를 미리 첨가하는 영향을 조사하였다. V$^{2+}$ 이온의 농도가 0.1 M 일 때 FVR 를 1.5:1 까지도 줄일 수 있음을 확인하였다.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.238-246
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• 1994

Partial oxidation of cyclohexane by HOOH was carried out with the transition metal complexes composed of Fe(II) or Fe(III)/picolinic acid derivatives. The major products were turned out to be cyclohexanone and cyclohexanol wlth the one/ol ratios of 3~10. The best performance was observed in a mixed solvent of pyridine/acetic acid(volume ratio 2.5:1, pH 5.3) and optimal temperature was $25{\sim}40^{\circ}C$. It was known that cyclohexyl hydroperoxide is the reaction intermediate, and that the reaction dominantly follows non-radical pathways which was ascertained from the results of the adamantane oxidation and radical trap experiments.

• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.33-36
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• 1985

The luminescence intensity of $Tb^{3+}$ bound to picolinic acid, squaric acid, and 2,3-pyrazinedicarboxylic acid has been studied in water and water-ethanol mixtures. It has been found that the emission intensity of $Tb^{3+}$ in the complexes is enhanced with the increase of ethanol content in water-ethanol mixtures. Several factors affecting on the emission intensity of $Tb^{3+}$ in waterethanol mixtures are discussed.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.138-142
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• 1989

Three oxovanadium(IV) complexes with bidentate ligands having only oxygen donor atoms, benzohydroxamic acid (Hben), 8-hydroxyquinoline-N-oxide(Hhqno) and picolinic acid-N-oxide (Hpicn) are prepared and magnetic and spectroscopic properties are investigated for the complexes $VO(ben)_2,\;VO(hqno)_2\;and \;VO(picn)_2.$ Magnetic data together with IR results strongly indicate that dimeric intermolecular interaction is significant in $VO(ben)_2$ while the presence of polymeric V-O${\cdot}{\cdot}$V-O interaction is suggestive in $VO(picn)_2$. For all three complexes, three electronic d-d transitions were observed; extremely strong optical absorption of these bands of $VO(ben)_2$ in DMSO are supposed to be arised from a great metal-ligand covalency. Some fundamental vibration modes of oxovanadium(IV) complexes were empirically assigned from the differences in the spectrum of metal complexes with free ligand.