• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.87-95
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• 1995

A rapid and selective co-extraction systems of copper and zinc-thiocyanate complex into various types of alkylamine for the simultaneous determination of two metal ions by atomic absorption spectrometry and ion chromatograph have been proposed. The quantitative extractions of Cu(II) and Zn(II) at 0.1 M-thiocyanate and 0.1 M-HCI were achieved with Aliquat 336-$CHCl_3$. The detection limits of Cu and Zn were 2 ppb and 0.9 ppb respectively.

• YAKHAK HOEJI
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• v.13 no.1
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• pp.38-42
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• 1969

Chloropentammine chromium(III) chloride를 출발물질로 하여 여러가지의 thiocyanatoammine계 착화합물을 합성하는 실험에 있어서 그 수득량이 예상보다 매우 적고 그 염의 모액이 농적자색이라는 점으로 보아 그 모액중에 어떠한 다른 착화합물이 다량 형성되어 있으리라고 추측하여 그 분리를 시도하였다든바 미려한 적자색의 결정을 얻었다. 그리고 분석에 의하여 이 물질이 potassium hexathiocyanatochromate(III) 임을 증명하였다. Cr$^{+++}$ 의 thiocyanate 착화합물형성에 관하여는 Niel Bjerrm$^{(8)}$에 의한 보고문이 있고 또 이들의 제법으로서는 Roesler$^{(9)}$들에 의하여 Potassium chromium alum에서부터 이 물질을 만드는 방법만이 보고되어 있을뿐이다. 따라서 Chloropentammine chromium(III) chloride에서 부터 이 물질을 만드는 이 새로운 방법이 이러한 화합물들의 제법으로서 앞으로 이용될 수 있는것으로 사료한다. 제조 방법: Chloropentammine chromium(III) chloride 3g을 KSCN 24g, 빙초산 24ml및 물 48ml의 혼합수용액에 현탁시킨 혼합물을 처음에는 잘 교반하면서 가온하고 다음 완전히 용해될때까지 끊인다. 냉각시킨 다음 생성된 증황색의 침반 Thiocyanatopentammine chromium(III) thiocyanate를 여과하고 여액 65ml에 KSCN 50g을 추가하여 완전용해시킨다. 이 용액을 방냉시키면 적자색의 미려한 결정이 석출되므로 이 결정을 여과하여 ethanol로 세척하고 진공 desiccator중에서 건조시켰다. 수득량 1.2~1.3g.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.760-763
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• 1992

A new ${\beta}$-lactam compound, 6-thiocyanopenicillanic acid(1a) was prepared by the reaction of diazonium salt of 6-aminopenicillanic acid with sodium thiocyanate. Reaction of 6-thiocyanopenicillanic acid(1a) with p-nitrobenzyl bromide, chloromethylpivalate and 1-chlorodiethylcarbonate, respectively, afforded the corresponding esters(1b∼d)

• Natural Product Sciences
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• v.8 no.2
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• pp.48-51
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• 2002

Antioxidative properties of fifteen anthraquinone derivatives, including eleven atural anthraquinones isolated from the roots of Morinda elliptica and four from synthetic origin were evaluated using thin layer chromatography (TLC), ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Five of the compounds, nordamnacanthal, damnacanthal, 2-formyl-1-hydroxyanthraquinone, morindone and alizarin showed higher antioxidative activity than standard natural antioxidant, ${\alpha}-tocopherol$, on the FTC assay. Morindone and alizarin showed the strongest antioxidant activity. The results from the bioassay using TBA method correlated well with the results of the FTC method.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.127-139
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• 2014

Hard-Soft Acid-Base (HSAB) 이론은 일반적인 유기, 무기반응의 반응성을 설명하는데 사용되어 왔다. 밀도범함수이론(DFT)을 기반으로 한 계산을 통하여 반응을 기술하기 위해 필요한 화학 퍼텐셜, global/local hardness/softness와 Fukui 함수 등을 얻을 수 있다. B3LYP 수준 하에서 DFT 양자계산을 이용하여 유기 반응을 분석했을 때 local HSAB 이론의 적용여부와 장단점을 알아보고자 하였다. 1-subtituted 다이엔과 비대칭 친다이엔체를 이용한 딜스-알더 반응의 경우 local HSAB 이론을 적용시켜, 오쏘 이성질체가 주 화합물인 이유를 설명할 수 있었다. 작용기를 변화시켰을 때 나타나는 차이점에서 규칙적인 경향성을 볼 수 없다는 사실을 통해서 전자, 입체 효과로 딜스-알더 반응을 분석할 수 없었던 이유를 이해할 수 있었다. Thiocyanate 음이온의 알킬화 반응의 경우 local HSAB 이론을 적용시켰을 때, 얻은 값을 통해서 반응 지점의 선호도를 예측할 수 없었는데 이는 thiocyanate를 생성하는 반응이 속도론적 지배 하에서 우세하는 반응이기 때문이다.

• YAKHAK HOEJI
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• v.47 no.4
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• pp.212-217
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• 2003

We have carried out the antioxidative activity of nuts species for the development of antioxidant from natural products. From our previous report, EtOAc and n-BuOH extracts of acorn hull and chestnut hull were found to have a strong antioxidative activity in various antioxidant experiment. In the continuous study, we isolated several compounds from EtOAc and n-BuOH extracts of acorn hull and chestnut hull by fractionation using column chromatography. The structures of isolated compounds were identified as catechin, naringenin and ellagic acid on the basis of their spectroscopic properties and by comparison of their physical and spectra data with published value. Antioxidative activities of catechin, naringenin and ellagic acid were measured by DPPH, ferric-thiocyanate and Rancimat method.

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.836-841
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• 1994

The polymer matrix effect on the selectivity, response rate and reproducibility for coextraction type anion-selective optode membranes were investigated with DOA-plasticized PVC, PVC/hydroxylated PVC, PU/hydroxylated PVC and DOS-plasticized CTA matrices. Optode membranes were prepared with TDMACl and ETH2412 dissolved in one of the four solvent polymeric matrices. The PU/hydroxylated PVC and PVC-based membranes have almost the same selectivity coefficients, while the CTA-based membrane is more selective toward lipophilic anions. The membrane with PU/hydroxylated PVC adhered strongly to a glass surface, and showed highly reproducible and relatively rapid response. Very poor adhesion of PVC/hydroxylated PVC and CTA-based membranes limited the usability of those membranes as sensor components. Based on these results, and considering the biocompatibility for clinical samples, the optode made with PU/hydroxylated PVC was applied to determine the thiocyanate ion in human saliva. The results obtained with this simple device were comparable to those with rather complicated ISE methods.

• Journal of the Korean Society of Food Culture
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• v.22 no.3
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• pp.336-341
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• 2007

Antioxidant activity of Astragalus membranaceus, Polygonatum stenophyllum, Angelica gigas, Acanthopanax sessiliflorus and Angelica pubescens extracts cultivated in Jecheon prepared with different solvents were determined by 1,1-diphenyl-2-picrylhydrzyl(DPPH) radical scarvenging ability and thiocyanate method . The highest hydroxy radical scarvenging activity was shown in Acanthopanax sessiliflorus, while the lowest was in Polygonatum stenophyllum. Angelica gigas showed strong antioxidant activity by thiocyanate method. Methanol extracts and water extracts showed higher antioxidant activities than ethanol extracts. Angelica pubescens showed the highest polyphenol contents and Acanthopanax sessiliflorus showed the highest flavonoid contents. Direct correlation between the hydroxy radical scavenging activity and polyphenol contents or flavonoid contents was established by simple regression(r>0.8) in each solvent extracts. Among medicinal plants cultivated in Jecheon, Acanthopanax sessiliflorus and Angelica pubescens showed strong antioxidant activities. These results suggest that methanol or water extracts of several medicinal plant cultivated in Jecheon could be used as natural antioxidants.

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.228-231
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• 1998

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.215-216
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• 2005