• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1767-1770
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• 2003

A simple, rapid and sensitive spectrophotometric method is herewith proposed for the determination of copper(II) by using diamine-dioxime ligand, meso-3,6,6,9-tetramethyl-4,8-diazaundecane-2,10-dione dioxime or meso-HexaMethyl Propylene Amine Oxime (meso-HMPAO). This method is based on the formation of a stable 1 : 1 red-pink complex between copper(II) and meso-HMPAO in aqueous solution. Absorption measurements were carried at 497 nm, with a molar absorptivity value of 338 L $mol^{-1}\;cm^{-1}$. Beer's law was obeyed over the concentration range of 0.5-370 ${\mu}$g $mL^{-1}$ with a Sandell's sensitivity value of 0.18 ${\mu}$g $cm^{-2}$. The proposed method has been successfully applied for determination of copper(II) in foodstuffs and pharmaceutical samples. The results obtained from this method are comparable with those obtained AAS.

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1444-1448
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• 2003

The microsurface adsorption - spectral correction (MSASC) technique has been applied to the interaction of indigo carmine (IC) with cetyltrimethylammonium bromide (CTAB). The aggregation of IC on CTAB obeys Langmuir isothermal adsorption. The results show that both the monomer complex $IC{\cdot}CTAB$ and the micellar complex $(IC{\cdot}CTAB)_{78}$ were formed. The binding constant of the monomer complex was calculated to be $K_{IC{\cdot}CTAB}$ = 2.20 ${\times}10^5L{\cdot}mol^{-1}$, and the molar absorptivity of the micellar complex was calculated to be ${\varepsilon}_{(IC{\cdot}CTAB)78}\;^{560nm}$ = 8.58 ${\times}10^5L{\cdot}mol^{-1}{\cdot}cm^{-1}$. The aggregation was applied to the determination of cationic surfactant in wastewater.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1764-1768
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• 2004

The present work reports on the investigations based on the interaction of sodium hydroxide with catechol derivatives. The first derivative spectra allowed the simultaneous determination of levodopa and carbidopa. The calibration graph was constructed from the first derivative signals by measuring $^1D$ at 350 nm for standard samples containing between 3 and 30 mg $L^{-1}$ of levodopa and at 305 nm for standard samples containing between 3 and 80 mg $L^{-1}$ of carbidopa. This method offers the advantages of simplicity, rapidity, selectivity and higher sensitivity than most of the existing spectophotometric methods.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.197-200
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• 2009

A simple dye having phenol and indole moieties was synthesized and its chromogenic signaling behaviors for the determination of water content in organic solvents were investigated. The compound revealed a pronounced chromogenic behavior in response to the variation of water content in water miscible aprotic organic solvents of acetone, acetonitrile, THF, and dioxane. Significant red shifts and changes in absorption spectra allowed a ratiometric analysis of the signaling behavior. The chemosensing behaviors were particularly pronounced in water content in less than 10% that is suitable for the application of the compound as a probe for the determination of water content in binary aqueous organic solutions having lower water content.

• Journal of the Korean Chemical Society
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• v.11 no.1
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• pp.8-11
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• 1967

A method of determination of gold in ores has been established: Disolved ore solution is evaporated to dryness, redissolved with 0.1N HCl then chloroaurate formed is adsorbed on anion exchange resin, Dowex $1\;{\cdot}\;{\times}4$. The resin is ignited and the residue is dissolved with HCl-$HNO_3$. After evaporation of the acid, and then dilution with water, sodium azide is added. The gold is extracted with amyl alcohol from the solution buffered to pH 6. The gold is determined by measuring absorbancy of the alcohol layer spectrophotometricaly at $385m{\mu}$. Various factors, HCl concentration, amount of the resin rate, if adsorption, foreign ions, effecting to the method, have been examined. This method seems to be satisfactory for the determination of gold presented dawn to 1g per metric ton in ore.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.29-32
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• 1961

Two methods for the determination of Cesium-137 in various foods(ashes) were compared. The one comprises two steps, the first being the separation of alkalies as cobaltinitrites or perchlorates by the radiochemical method, and the second being the measurement of photopeak area due to the presence of Cs-137 by the use of scintillation spectrometer. The other method is the direct subjection of ash samples to the spectrometry without the radiochemical separation. The combined contribution of K-40 and Rb-87 to the spectrum was not found on account of the difference in energies of these nuclides. These two methods gave, a good agreement in the determination of Cs-137 in 50-100g ash samples of vegetables or cereals under investigation.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.84-87
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• 1961

A polarographic method for rapid determination of Uranium in the presence of foreign ions was proposed. The method is based on the measurement of polarogram in the sulfuric acid as supporting electrolyte. In this medium Uranyl ions give well defined reduction waves, and half-wave potentials are -0.19V vs. S.C.E. as first wave, and uncertain volt. vs. S.C.E. as second wave in $2.4 N-H_2SO_4.$ The first wave has a linear relationship between the concentration of Uranyl ion and wave height. The author also studied a method for rapid determination of Uranium in Korean monazite sand without eliminating the foreign ions. The Korean monazite sands were analyzed by this method and satisfactory result were obtained.

• Bulletin of the Korean Chemical Society
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• v.20 no.1
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• pp.59-64
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• 1999

Based on the study of hydrolysis behaviour of U(Ⅵ) ion and major fission product metal ions such as Cs(Ⅰ), Ce(Ⅲ), Nd(Ⅲ), Mo(Ⅵ), Ru(Ⅱ), and ZR(Ⅳ) in the titration media, the performance of noncomplexing-alkalimetric titration method for the determination of free acid in the presence of these metal ions was investigated and its results were compared to those from the completing methods. The free acidities could be determined as low as 0.05 meq in uranium solutions in which the molar ratio of U(Ⅵ)/H+ was less than 5, when the end-point of titration was estimated by Gran plot. The biases in the determinations were less than 1% and about +3% respectively for 0.4 meq and 0.05 meq of free acid at the U(Vl)/H+ molar ratio of up to 5. Applicability of this method to the determination of free acid in spent fuel solutions was confirmed by the analysis of nitric acid content in simulated spent fuel solutions and in a real spent fuel solution.

• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.50-56
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• 1998

A solvent sublation was studied for the determination of trace Cd, Co, Cu and Ni in water samples. Ammonium pyrrolidine dithiocarbamate (APDC) was used as a complexing agent. Experimental conditions such as pH of solution, amounts of APDC, the type and amount of surfactant, the type of solvent, etc. were optimized for the effective sublation of analytes. After metal-PDC complexes were formed in sample solutions of pH 2.5, the precipitate-type complexes were floated in a flotation cell with an aid of sodium lauryl sulfate as a surfactant and by bubbling with nitrogen gas. The precipitates were dissolved and separated into the surface layer of methyl iso-butyl ketone (MIBK). The analytes preconcentrated were determined by a graphite furnace atomic absorption spectrophotometry (GF-AAS). Extractability of each element was 88% for Cd(Ⅱ), 86% for Co(Ⅱ), 95% for Cu(Ⅱ) and 76% for Ni(Ⅱ), respectively. And this procedure was applied to the analysis of real samples. From the recoveries of more than 92%, it was concluded that this method could be simple and applicable for the determination of trace elements in various water samples of a large volume.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.595-598
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• 2011

Cetirizine hydrochloride reacted with $BiI_4^-$ in an acidic aqueous solution to form precipitate. After centrifugation, the atomic emission intensity of $Bi^{3+}$ contained in the supernatant solution was measured at the characteristic wavelength of 206.170 nm. The difference between the spectral signal intensity of the blank solution and that of the supernatant, ${\Delta}I$, was linearly related to the concentration of cetirizine hydrochloride. As a result, a new inductively coupled plasmaatomic emission spectrometric (ICP-AES) method was developed for the analysis of cetirizine hydrochloride. The linear range was from 27.7 to 184.8 $mg{\cdot}L^{-1}$, with a correlation coefficient (r) of 0.9961 and a detection limit of 9.6 $mg{\cdot}L^{-1}$. This method is simple and accurate, Without using toxic organic solvents, and is feasible for the quality control of cetirizine hydrochloride tablets and capsules.