• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.267-270
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• 2013

• Journal of Plant Biology
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• 제38권1호
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• pp.1-10
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• 1995

Photoinhibition and its recovery of spectrally adapted Anacystis nidulans were studied. Phycocyanin and Chl content and phycocyanin/Chl ratio were increased in cells grown under blue-green light compared with those grown in white light. Photosynthetic activities of white light and blue-green light grown cells were reduced by 50% after 15 min and 10 min of photoinhibitory light treatment (1.2 mmol·m-2s-1), respectively, largely due to the decline of PSII activities. However, their activities were recovered fully after 30 min incubation under weak light. Treatment of rifampicin and chloramphenicol magnified the photoinhibitory effects and suppressed the recovery with disappearance of susceptibility to photoinhibition and delayed the recovery process, indicating no significant differences in phosphorylation, dephosphorylation and protease activity between two cells. Therefore, it is suggested that the increased sensitivity of blue-green adapted cells might be attributed to the decline of protein synthesis, and phosphorylation-dephosphorylation of protein and protease activity might be involved in the recovery process.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1556-1560
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• 2012

A simple highly versatile and efficient method has been developed for the three-component coupling of aldehydes, amines and alkynes to prepare propargylamines, in the presence of a catalytic amount of $BiCl_3$. The advantages of methods are high yield, mild reaction conditions, no environmental pollution and easy work up procedure.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2890-2896
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• 2012

A simple regioselective synthesis of cinnoline derivatives was achieved by a one-pot three component synthetic methodology. New substituted 7,8-dihydrocinnolin-5(6H)-ones are prepared via one-pot three component reaction of arylglyoxals with 1,3-cyclohexanedione and dimedone in the presence of hydrazine hydrate in moderate to good yields.

• 대한화학회지
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• 제63권6호
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• pp.435-439
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• 2019

An efficient one pot multicomponent synthesis of pyrimidinone derivatives of Biginelli type is described. 4-amino-6-aryl-pyrimidine-5-carbonitrile molecules were synthesized efficiently via three-component Biginelli-type condensation of aldehyde, malononitrile, and semicarbazone as urea substituent in the presence of a catalytic amount of PEG-400 as green medium under microwave irradiation. The reactions proceeded efficiently in the presence of microwave radiation to afford the desired products in good to excellent yields. Products have been confirmed by IR, and NMR spectral analysis. All the molecules were tested for their antimicrobial activity against E. coli, S. aureus, P. aeruginosa and C. tropicalis. Some of the compounds have shown moderate to good inhibition efficiency against both gram-positive and gram-negative bacteria. The potent activity was observed against the fungal species with minimum inhibition concentration 12.5 ㎍/mL.

• 대한화학회지
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• 제51권4호
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• pp.339-345
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• 2007

Urea는 높은 온도(60~80 °C)의 수용액 상태에서 PtCl2, H2[PtCl6]·6H2O, H2[IrCl6] Ni(CH3CO2)2 와 반응해서 각각 (1)[PtCl2(Urea)]·2H2O, (2)(NH4)2[PtCl6], (3)(NH4)2[IrCl6]·H2O, (4)[Ni2(OH)2(NCO)2(H2O)2]의 complexes를 생성 한다. complexe 1에서 urea는 중성 bidentate 리간드로써 Pt(II)와 배위한다. complexe 2,3,4에서는 높은 온도에서 반 응하는 동안 배위 urea분자들이 분해되고 다양한 반응생성물들을 얻을 수 있다. 모든 complexes은 각각 적당한 수득률 로 dark green(1) yellow(2), pale brown (3) faint green(4)의 침전물로 분리된다. 반응생성물은 열분석, IR, 1H and 13C NMR spectra에 의해 측정 되었다. 이 complexes의 구성을 설명하는 일반적인 매카니즘이 제시되었다.

• 공업화학
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• 제24권6호
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• pp.650-655
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• 2013

본 연구에서는 Pd/C 촉매를 이용하여 무수말레인산(maleic anhydride) 수용액상에서 수소화 반응을 통해 호박산(succinic acid) 합성을 진행하였으며, 그에 따른 최적 공정 조건을 도출하고자 하였다. 반응 온도 및 반응시간에 따른 호박산 순도의 차이는 크지 않았으나 압력과 교반속도가 증가함에 따라 불순물의 생성이 줄고, 호박산의 순도가 증가함을 확인하였다. 실험 결과 본 수소화 반응에서는 압력과 교반속도가 기체-액체 간 물질전달저항을 감소시켜 반응속도를 증가시킬 수 있는 가장 중요한 변수임을 확인하였으며 이에 따라 압력과 교반속도에 대한 반응속도를 구하였다. 반응압력이 5 bar에서 10 bar로 2배 증가 시, 반응속도는 2.14배 증가하였으며 교반속도가 300 rpm에서 700 rpm으로 2배 증가 시, 반응속도는 2.36배 증가함을 확인할 수 있었다.

• Journal of Electrochemical Science and Technology
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• 제10권3호
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• pp.313-320
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• 2019

In this study, cobalt diselenide ($CoSe_2$) and the composites ($CoSe_2@RGO$) of $CoSe_2$ and reduced graphene oxide (RGO) were synthesized by a facile hydrothermal reaction using cobalt ions and selenide source with or without graphene oxide (GO). The formation of $CoSe_2@RGO$ composites was identified by analysis with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and scanning electron microscopy (SEM). Electrochemical analyses demonstrated that the $CoSe_2@RGO$ composites have excellent catalytic activity for the reduction of $I_3{^-}$, possibly indicating a synergetic effect of $CoSe_2$ and RGO. As a consequence, the $CoSe_2@RGO$ composites were applied as a counter electrode in DSSC for the reduction of redox couple electrolyte, and exhibiting the comparable power conversion efficiency (7.01%) to the rare metal platinum (Pt) based photovoltaic device (6.77%).

• Journal of Electrochemical Science and Technology
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• 제6권4호
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• pp.111-115
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• 2015

In this work electrochemical oxidation of Ascorbic acid (AA) on the surface of Cobalt nano particle modified carbon paste electrode (CoNPsMCPE) was studied in alkaline media. CoNPs were green synthesized using Piper longum and a mixture of 5% (w/w) of it were made with carbon paste. CoNPs showed good electrocatalytic activity in alkaline media. Cyclic voltammetry (CV) and chronoamperometry (CA) were used to study the electrochemical performance of CoNPsMCPE. The number of monolayers on the surface of electrode was calculated as 1.08×10⁹ mol cm⁻² that is equal to that of metal Cobalt electrode. Diffusion coefficient of AA was determined using CA analysis which was equal to 1.5×10⁻⁶cm² s⁻¹.

• 한국염색가공학회지
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• 제28권3호
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• pp.156-163
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• 2016

The 6 novel super hydrophobic bluish-green dyes, showing the maximum absorption at 600~650nm, were synthesized to dye polyolefin fibers such as polypropylene and high strength polyethylene fibers. Their absorption spectra appeared almost the same at visible range, which meant the length of alkyl substituents did not affect on color appearance of the dyes. The optimum length of alkyl group was determined as hexyl substituents from the practical point of view. From the dyeing results, the optimum dyeing condition was $130^{\circ}C$ for 1 hour. The good fastness ratings to washing, rubbing were obtained showing 4-5 for both fibers. Light fastness was obtained also good rating 4 for both fibers.