• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2316-2318
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• 2011

A novel technology has been developed for the synthesis of thioglycolic acid (TGA)-capped CdSe quantum dots (QDs) in aqueous medium. The reaction was carried out in air atmosphere with one-pot by using $SeO_2$ to replace Se or $Na_2Se$. The technological parameters including refluxing time, pH values and molar ratios of selenium to cadmium had significant influence on the luminescence properties of CdSe QDs. Furthermore, the obtained QDs were characterized by fluorescent spectroscopy, X-ray powder diffraction (XRD) and transmission electron microscopy (TEM), respectively. The results demonstrated that the CdSe QDs were of zinc-blended crystal structure in a sphere-like shape.

• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.93-101
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• 1997

A modified procedure for electroplating wastewater treatment using formaldehyde and hydrogen peroxide can destroy free cyanide. The representative diagram which is quite sensitive on reaction temperature is showed for this kinds of treatment. Principally free cyanide and some kinds of cyanide complex should be treated first, and then toxic heavy metals can be removed because cyanide component will be inhibited to remove other pollutants, if it is not destroyed perfectly. Formaldehyde and hydrogen peroxide are added in controlled amounts to cyanide treatment tank. Reasonable amounts of these chemicals are (HCHO/CN)=0.9 and ($H_2O_2/CN$)=1.1 in molar ratios, it is also variable on reaction temperature. Of course, actual treatment processes depending on plating material and chemical are good applicable, also to systematize operation manual for treating electroplating wastewater process, further works are desirable.

• Journal of Pharmaceutical Investigation
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• v.15 no.3
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• pp.130-139
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• 1985

Inclusion compounds of suprofen with ${\alpha}-$ and, ${\beta}-cyclodextrins\;({\alpha}-CyD,\;{\beta}-CyD)$ were studied in comparison with suprofen alone and commercial suprofen capsules. Inclusion compound formations of suprofen with ${\alpha}-$, and ${\beta}-CyDs$ in aqueous solution and in solid state were confirmed by UV absorption, circular dichroism spectroscopies, IR spectroscopy, differential scanning calorimetry and X-ray diffraction measurements. Solid inclusion complexes were prepared by freeze-drying method, and their molar ratios were found to be 1 : 1. The dissolution rate of inclusion complexes of suprofen with CyDs was notably higher than that of suprofen alone.

• YAKHAK HOEJI
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• v.30 no.2
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• pp.87-95
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• 1986

Inclusion complexation of $\alpha$-cyclodextrin($\alpha$-CD), $\beta$-cyclodextrin($\beta$-CD) and tri-O-methyl-$\beta$-cyclodextrin(tri-O-methyl-$\beta$-CD) with chlorpamide(CPA) in aqueous solution and in the solid state were studied by the solubility method, spectroscopy (UV, IR), differential scanning calorimetry (DSC) and powder X-ray diffractometry, and all their molar ratios were found to be 1:1. The solid complexes of CPA with three kinds of cyclodextrins were prepared by a freezedrying method, and their dissolution behaviors were examined. As a result, the release of CPA from the inclusion complexes was significantly improved. The intrinsic dissolution rate of CPA in cyclodextrin inclusion complexes was about 51 times ($\alpha$-CD inclusion complex) and 12 tmies ($\beta$-CD inclusion complex) larger than that of intact CPA.

• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.119-124
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• 1995

Conventional alkaline catalytic procedure, including sodium methoxide-methanol N, N, N', N'-tetramethyl guanidine-methanol, and acid-catalytic methods of $BF_{3}-methanol$ and HCI-methanol, have been applied for preparing methyl esters from the triacylglycerols of Trichosanthes kirilowiil seeds containing conjugated trienoic acids. The alkaline catalytic methods produce the methyl esters quantitatively without isomerization of the conjugated trienoic acids, but the acid-catalytic ones destroy almost the molecules of conjugated trienoic acids during transesterification of the triacylglycerols although the molar ratios of monoenoic and dienoic acids (non-conjugated) to saturated acids are in good agreement with those obtained from the alkaline methods.

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1211-1216
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• 2004

The interaction of the antitumour agent doxorubicin with calf thymus DNA is investigated in an aqueous solution at a pH level of 6-7 with molar ratios of 1/10. A UV-resonance Raman spectroscopy and surface enhanced Raman spectroscopy are used to determine the doxorubicin binding sites and the structural variations of doxorubicin-DNA complexes in an aqueous solution. Doxorubicin intercalates with adenine and guanine via a hydrogen bond formation between the N7 positions of purine bases and the hydroxyl group of doxorubicin.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.779-785
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• 2004

Syn (or anti) cinnamaldehydeoxime (1a, b) undergoes Diels-Alder addition to tetrabromo-p-benzoquinone (2)in dry xylene in 1 : 1 and 2 : 1 molar ratios to give the mono- and diadducts 3 and 4a, b respectively. The reaction of 3 with thioamides in ethanol gave thiazoloquinoline diones 6a-d, whereas with acid amides in ethylene glycol, it gave oxazoloquinolinediones 12a-f.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2029-2033
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• 2007

Hydrotalcite, layered double hydroxides (LDH), with hexagonal morphology has been rapidly synthesized by microwave reaction within 1 hour by urea hydrolysis from homogeneous solution. Different synthesis parameters, Mg/Al molar ratio, microwave reaction temperature and microwave power were systematically investigated. Pure hydrotalcite phase was obtained for Mg/Al ratios of 2:1 and 3:1, and higher reaction temperature gave higher crystallinity. The hydrotalcite synthesized at 600W power shows the highest crystallinity and more homogeneous crystal size distribution. The hydrotalcite samples were characterized by powder X-ray diffraction (XRD), simultaneous thermogravimetric/differential thermal analysis (TG/DTA), Fourier Transform Infrared (FT-IR) and Scanning electron micrograph (SEM).

• Proceedings of the Korean Nutrition Society Conference
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• 2001.05a
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• pp.148.2-148
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• 2001

• Bulletin of the Korean Chemical Society
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• v.22 no.7
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• pp.678-684
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• 2001

Porous silica-pillared montmorillonites were prepared by simultaneous intercalation of dodecylamine-TEOS [tetraethylorthosilicate, Si(OC2H5)4] into the H-montmorillonite and intragallery amine-catalyzed hydrolysis of TEOS. Mixtures of the H-montmorillonite, dodecylamine and TEOS at molar ratios of 1 : 2 : 15-30 and 1 : 2-6 : 20 resulted to swollen and viscous gel once at room temperature, allowing intercalation compounds which dodecylamine and TEOS were simultaneously intercalated into interlayer of H-montmorillonite. The hydrolysis of the gallery TEOS was conducted in water solution for 40 min at room temperature, affording siloxane-pillared H-montmorillonite. Calcination of samples at 500 $^{\circ}C$ in air resulted in silica-pillared montmorillonite with large specific surface areas between 403 and 577 m2 /g, depending on the reaction stoichiometry. The reaction at H-montmorillonite : dodecylamine : TEOS reaction stoichiometries of 1 : 2 : 15 and 1 : 4 : 20 resulted in high specific surface areas and mesopores with a narrow pore size distribution. Result indicates that the intragallery-amine catalyze the hydrolysis of gallery-TEOS and simultaneously have a role of gallery-templated micellar assemblies.