• 약학회지
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• 제13권2_3호
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• pp.80-83
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• 1969

Acetylsalicylic acid gives a water-insoluble violet complex with $<\alpha>$-Picolin-Cu(II) reagent. The Complex is extractable well with a mixture of $<\alpha>$-Picolin-tetrachloromethane solution. The Complex salt dissolved in the mixed solution shows a maximum absorption at 620 m$<\mu>$. It has a melting point at $171^{\circ}C-$173^{\circ}C and molar ratio of Acetylsalicylic acid: Cu(II): $<\alpha>$-Picolin was estimated as 2:1:2 by continuous variation method and chelate titration method.

• 생명과학회지
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• 제17권2호통권82호
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• pp.266-271
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• 2007

BPA는 플라스틱 가소제 및 폴리카보네이트 플라스틱 생산의 모노머로 광범위하게 사용되어 왔으며, 년간 세계적으로 640,000톤 이상이 생산되고 있다. 내분비장애활성을 가진 BPA는 수계 및 공업용수에서 흔히 발견되며, 이의 분석은 HPLC 및 GC 등 기기분석에 의존하고 있다. 그러나 본 연구에서는 환경 및 생활용품에 잔류하는 BPA를 신속, 정확하고, 경제적으로 분석할 수 있는 분광학적 정량방법을 개발하고자 하였으며, 이를 위해 $FeCl_3{\cdot}6H_2O$와 $K_3Fe(CN)_6$를 사용한 비색정량법을 확립하였다. 발색반응으로 생성된 청색화합물의 ${\lambda}max$ 및 반응특이성을 조사하였으며, 최적반응조건(시간, 온도, pH, 농도, 부피, 반응안전성)을 검토하였다. 확립된 발색반응조건에서 BPA에 대한 검량곡선(${\lambda}_{750}$=0.61 BPA $[{\mu}M]$+0.07155, $R^{2}$=0.992)을 얻었으며, 신규 확립된 비색정량법을 이용하여 토양, 수계 및 생활용품의 BPA 분석을 시도한 결과, HPLC 분석시스템과 유사한 결과를 얻을 수 있었다. 본 BPA 및 관련물질에 대한 비색정량법은, 기기분석에 비해 빠르고, 경제적이며, 대량의 시료를 일시에 취급할 수 있어 기기분석의 보완분석으로도 우수하며, BPA 분해산물은 발색반응을 나타내지 않아, 자연계로부터 BPA 분해균주 선별 등에 매우 유용하게 이용될 수 있다.

• 한국환경보건학회지
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• 제38권2호
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• pp.136-141
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• 2012

Objectives: The objective of this study was to investigate whether the ammonia nitrogen concentration of aqueous samples such as drinking water can be determined by measuring the saturation of the samples colored by indophenol method. Methods: A color saturation measurement system was constructed by connecting a notebook computer to an image acquisition device composed of a PC camera and a light source, and was then used to measure the saturation of samples colored by blue indophenol complex. Results: Between two available light sources, a fluorescent lamp was selected due to its demonstrating better linearity between color saturation and ammonia nitrogen concentration. Prediction by quadratic regression was more accurate than by linear regression, and prediction by quadratic regression in the concentration range of 0.1-1.0 $mg/l$ was more accurate than in the concentration range of 0.0-1.0 $mg/l$. Regression-based predictions over 0.25 $mg/l$, 0.55 $mg/l$ and 0.75 $mg/l$ concentrations were implemented both by spectrophotometric method and by measuring color saturation. In the case of 0.25 $mg/l$, the predicted concentration by spectrophotometric method was $0.256{\pm}0.0076\;mg/l$ and the predicted concentration by measuring color saturation was $0.246{\pm}0.0086\;mg/l$ (p=0.051). In the case of 0.55 $mg/l$, they were $0.561{\pm}0.0068\;mg/l$ and $0.564{\pm}0.0166\;mg/l$ (p=0.660). In the case of 0.75 $mg/l$, they were $0.755{\pm}0.0139\;mg/l$ and $0.762{\pm}0.0088\;mg/l$ (p=0.215). Conclusions: There were no statistically significant differences (p>0.05) between the data from the two methods in all three of the concentrations. Therefore, the color saturation measurement method proposed in this paper may be considered applicable for determining the ammonia nitrogen concentration of aqueous samples such as drinking water.

• 대한화학회지
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• 제54권3호
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• pp.283-286
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• 2010

지르코늄의 부유-분광 광도의 측정에 대한 감도가 좋고 재현성 있는 방법이 기록되었다. 그 방법은 지르코늄과 자일렌오렌지(XO)착물 형성에 기초하였고 그것은 격렬한 진탕에 의해 수용액 상과 n-헥산의 표면에 떠있게 된다. 수용액과 n-헥산을 폐기함에 따라 분리된 깔대기의 벽에 있던 흡착된 착물은 작은 부피의 메탄올 용액으로 해리되어진다. 그리고 그것의 흡광도는 429 nm에서 측정되었다. PH, HCl, XO의 농도, n-헥산 부유 용매의 부피, 지속시간과 진탕시간과 같은 다른 변수의 효과가 연구되었다. 보정곡선은 0.9991의 상관계수를 갖는 지르코늄의 7 ~ 120 ng/mL의 범위에서 선형이었다. 검출한계(LOD)는 58 ng/mL이었다. 지르코늄의 50과 110 ng/mL 의 7개의 분할척정에 대한 상대표준편차(RSD)는 4.4와 3.0%였다. 이 방법은 물샘플에서 지르코늄의 측정에 성공적으로 적용되었다.

• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1529-1532
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• 2005

A simple and cost effective method for separation and preconcentration of Ag(I) at the $10^{-7}\;mol\;L^{-1}$ level in the environmental and mineral samples is present. The method is based on the flotation of Ag(I)-iodide complex as an ion-associate with ferroin in pH of 4 from a large volume of an aqueous solution (500 mL) using nheptane. The floated layer was then dissolved in dimethylsulfoxide (DMSO) for the subsequent spectrophotometric determination. Beer's law was obeyed over a range of 2.0 ${\times}$ $10^{-7}$-4.0 ${\times}$ $10^{-6}$ mol $L^{-1}$ with the apparent molar absorptivity of 2.67 ${\times}$ $10^5$ L $mol^{-1}\;cm^{-1}$. The detection limit (n = 5) was 4 ${\times}$ $10^{-8}$ mol $L^{-1}$, and RSD (n = 5) obtained for 2.0 ${\times}$ $10^{-6}$ mol $L^{-1}$ of Ag(I) was 2.2%. The interference effects of a number of elements was studied and found that only $Hg^{2+}$ at low concentration, and $Pb^{2+}$, $Cd^{2+}$, $Cu^{2+}$, and $Fe^{3+}$ ions at moderately high concentrations were interfered. To overcome on these interference effects, the solution was treated with EDTA at a buffering pH of 4 and passed through a column containing Amberlite IR-120 ionexchanger resin, just before the flotation process. The proposed method was applied to determine of Ag(I) in a synthetic waste water, a photographic washing sample and a geological sample and the results was compared with those obtained from the flame atomic absorption spectrometry. The results were satisfactorily comparable with together, so that the applicability of the proposed method was confirmed in encountering with the real samples.

• 대한화학회지
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• 제19권5호
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• pp.343-350
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• 1975

염산수용액중에 존재하는 이리듐을 그 분자량 아민(Alamine 336)의 벤젠용액으로 추출한 바 20${\sim}$100${\mu}g$의 이리듐을 정량적으로 추출할 수 있음을 알았고 이때 이리듐 추출의 가능성에 관하여는 방사성 추적자(Ir-192)를 써서 확인하였다. 유기층에 추출된 화학종의 흡광도를 파장 322.5nm에서 측정한 결과 본 방법은 이리듐의 정량을 위한 미량분석법으로 사용할수 있음을 알았다. 이리듐이 아민층에 추출되는 메카니즘에 대한 설명을 시도하였다.

• BMB Reports
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• 제37권5호
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• pp.629-633
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• 2004

NADPH-cytochrome P450 reductase (CPR) transfers electrons from NADPH to cytochrome P450, and catalyzes the one-electron reduction of many drugs and foreign compounds. Various forms of spectrophotometric titration have been performed to investigate the electron-accepting properties of CPR, particularly, to examine its ability to reduce cytochrome c and ferricyanide. In this study, the reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH) by CPR was assessed as a means of monitoring CPR activity. The principle advantage of DPPH is that its reduction can be assayed directly in the reaction medium by a continuous spectrophotometry. Thus, electrons released from NADPH by CPR were transferred to DPPH, and DPPH reduction was then followed spectrophotometrically by measuring $A_{520}$ reduction. Optimal assay concentrations of DPPH, CPR, potassium phosphate buffer, and NADPH were first established. DPPH reduction activity was found to depend upon the strength of the buffer used, which was optimal at 100 mM potassium phosphate and pH 7.6. The extinction coefficient of DPPH was $4.09\;mM^{-1}\;cm^{-1}$. DPPH reduction followed classical Michaelis-Menten kinetics ($K_m\;=\;28\;{\mu}M$, $K_{cat}\;=\;1690\;min^{-1}$). This method uses readily available materials, and has the additional advantages of being rapid and inexpensive.

• 약학회지
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• 제33권3호
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• pp.141-148
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• 1989

The weak UV absorbing antihistaminics such as chlorpheniramine, triprolidine, tripelennamine and diphenhydramine were analyzed by charge-transfer spectrophotometric method. The results obtained are summarized as folows. It was possible to determine a weak UV absorbing antihistaminics using the intense charge-transfer UV bands in chloroform. Charge transfer complexes were formed in a 1:1 ratio between antihistaminics and iodine in chloroform. Linear relationship was found between absorbance and concentration in the range of $1.0\;{\times}\;10^{-5}M-5.0\;{\times}\;10^{-5}M$ for chlorpheniramine( ${\varepsilon}\;=\;2.082\;{\times}\;10^4$) and tripelennamine ( ${\varepsilon}\;=\;1.578\;{\times}\;10^4$), $1.0\;{\times}\;10^{-5}M-8.0\;{\times}\;10^{-5}M$ for triprolidine ( ${\varepsilon}\;=\;1.120\;{\times}\;10^4$) and $1.0\;{\times}\;10^{-5}M-1.0\;{\times}\;10^{-4}M$ for diphenhydramine ( ${\varepsilon}\;=\;9.900\;{\times}\;10^3$). Charge transfer complexes of chlorpheniramine, triprolidine and tripelennamine have absorption maxima at 293 nm and complex form of diphenhydramine has absorption maximum at 270 nm. By UV, IR spectra, it could be inferred that CT-complexes were formed by interaction between the basic nitrogen of antihistaminics as electron donor (non bonding electron) and iodine as electron acceptor (${\sigma}$ bonding electron).

• 대한화학회지
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• 제9권2호
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• pp.101-105
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• 1965

7-Nitroso-8-hydroxyquinoline-5-sulfonate(NHQS)는 pH 4.5에서 Co(Ⅱ)와 安定한 赤色 complex를 形成하므로 이것을 利用하여 NHQS에 依한 Co(Ⅱ)의 吸光光度定量方法을 檢討하였다. 吸光度는 528$m{\mu}$, $25^{\circ}C$에서 測定하였다. Co(Ⅱ)의 濃度 0.3∼6p.p.m에서 Beer의 法則은 成立하며 complex의 分子吸光係數는 $1.1{\times}10^4$이었다. 共存이온中 Fe(Ⅱ), Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ), Hg(Ⅰ), CN-, EDTA 等은 本定量에서 妨害가 된다. Complex의 組成을 몰比法과 連續變化法으로 檢討한 結果 NHQS와 Co(Ⅱ)의 몰比는 3:1이었다.

• 대한화학회지
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• 제34권6호
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• pp.616-621
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• 1990

UV-VIS 흡광광도법으로 Nd, Pr, Sm, Eu, Ho 및 Er을 정량할 때 스펙트럼 방해를 다원소 보정법으로 방법에 대하여 연구하였다. 개별희토류의 흡광도를 측정하고 또, Nd와 Pr의 혼합용액 및 Sm, Eu, Ho, Er의 혼합용액의 흡광도를 측정하여 몰흡광 계수를 구하고 이들로부터 상호 방해가 가장 적은 파장 즉, Nd(444.2nm), Pr(575.1nm), Sm(401.7nm), Eu(394.2nm), Ho(416.6nm), Er(379.7 nm)임을 알았다.