• Analytical Science and Technology
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• v.12 no.3
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• pp.243-247
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• 1999

After aconitine-type alkaloids have been isolated from the crude drug "Buza" as the precipitate, they could be identified with colour test, UV/Vis. absorption wavelength, TLC. The presence of aconitine-type alkaloids are confirmed by the reaction with the Reineke ion, $[Cr(NH_3)_2(SCN)_4]^{1+}$, and TCR ion, $[Co(SCN)4]^{2-}$, to produce the white precipitate or one of the containing from blue to yellowish blue. It is based on the formation of complex compounds by aconitine-type alkaloids with Reineke and TCR reagent. The method has been found to be simple, convenient and suitable for routine identification of aconitine-type alkaloids, related basic compounds, the crude drug "Buza" processed from the roots of certain Aconitum spp. plants(Ranunculaceae).

• Journal of the Korean Ceramic Society
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• v.51 no.4
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• pp.350-356
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• 2014

Recently, Chemical Vapor Deposition (CVD) synthetic diamonds have been introduced to the jewelry gem market, as CVD technology has been making considerable advances. Unfortunately, CVD diamonds are not distinguishable from natural diamonds when using the conventional gemological characterization method. Therefore, we need to develop a new identification method that is non-destructive, fast, and inexpensive. In our study, we employed optical microscopy and spectroscopy techniques, including Fourier transform infra-red (FT-IR), UV-VIS-NIR, photoluminescence (PL), micro Raman, and cathodoluminescent (CL) spectroscopy, to determine the differences between a natural diamond (0.30 cts) and a CVD diamond (0.43 cts). The identification of a CVD diamond was difficult when using standard gemological techniques, UV-VIS-NIR, or micro-Raman spectroscopy. However, a CVD diamond could be identified using a FT-IR by the Type II peaks. In addition, we identified a CVD diamond conclusively with the uneven UV fluorescent local bands, additional satellite PL peaks, longer phosphorescence life time, and uneven streaks in the CL images. Our results suggest that using FT-IR combined with UV fluorescent images, PL, and CL analysis might be an appropriate method for identifying CVD diamonds.

• KSBB Journal
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• v.5 no.2
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• pp.191-194
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• 1990

Tyrosine is a monohydrolic aromatic amino acid and DOPA is a tyrosine derivative containing dihydroxy group. DOPA can be synthesized from tyrosine by enzymatic reaction. The separation and quantitative determination of each component are very difficult in the reaction mixture. In the present study, two wavelengths giving maximum absorbance difference of each amino acid were determined using UV/VIS spectrophotometer by wavelength scanning and simple assay method was developed for the analysis of the reaction mixture of tyrosine and DOPA by measuring absorbances of reaction mixture. This method can be simply used for the analysis of the tyrosine and DOPA mixture because it does not require and procedure for the pretreatment of the reaction mixture.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.137-140
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• 2006

This paper describes a technique combining chemometrics with UV spectroscopy for the determination of the concentra tions of two tissue additives (i.e., wet strength and softening agents) in a cellulose fiber containing solution. In single as ent solutions, the concentration of the additive can be measured by UV spectroscopy at the wavelength where the species having absorption. For a binary (i.e., containing two additives) solution system, the spectral characterization is very complicated. However, if aided by a chemometrical calibration technique, each additive in the binary solution can be quantified simultaneously. The present method is very rapid and simple, it can easily perform a continuous measurement in the changes in the additives' concentration after fiber addition, and therefore this becomes a valuable tool for the adsorption kinetics study of chemical additives onto the cellulose fibers. The time-dependent adsorption behaviors of the wet-strength, softening agent, and their both on fiber were also presented.

• Carbon letters
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• v.10 no.4
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• pp.325-328
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• 2009

This cycloaddition of [70]fullerene with methyl azidoacetate in benzene under ultrasonic irradiated condition afforded the closed [5,6]-bridged aziridino[70]fullerene derivative, which was unusual product of cycloaddition to the 5,6-junction of fullerene. Its structure was determined by FAB-MS, UV-vis, $^1H-$ and $^{13}C$-NMR spectral data. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films were self-assembled using the layer-by-layer method on the reactive of glass slides functionalized with 3-mercaptopropyl trimethoxysilane. The functionalized glass slides were alternately soaked in the solution containing closed the [5,6]-bridged aziridino[70]fullerene and 4-aminothiophenoxide/hexanethiolate-protected gold nanoparticles. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films have grown up to 5 layers depending on the immersion time. The self-assembled nanoparticle multilayer films were characterized using UV-vis spectroscopy showed that the surface plasmon band of gold at 527 nm gradually became more evident as successive layers were added to the films.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.306-310
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• 2010

Petroleum visible markers (dye) have been used to distinguish different fuel classes and to prevent illegal mixing. It is difficult to recognize the real color of visible marker when the small amount of petroleum product was mixed in another fuel oil. In this study, we determined the two wavelengths (370 nm, 645 nm) which detect all Korean petroleum visible marker using UV/Vis spectrophotometer. Then we analyzed the visible marker using high performance liquid chromatography (HPLC) in two wavelength detectors. Also, we optimized the analytic method for petroleum visible marker in illegal mixed fuel oil.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.616-621
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• 1990

The spectrophotometric methods for the determination of Nd, Pr, Sm, Eu, Ho, Er were developed, using the multicomponent method of absorption spectra cointerference. The absorption spectra of individual Nd, Pr, Sm, Eu, Ho, Er, mixture of Sm, Eu, Ho, Er in hydrochloric acid solutions were investigated, and also a band register which includes the molar absorptions for all trivalent Nd, Pr, Sm, Eu, Ho and Er absorption band maxima were measured. The spectrophotometric determination of Nd, Pr, Sm, Eu, Ho and Er were investigated using the analytically significant absorption bands at 444.2, 575.1, 401.7, 394.2, 416.6, and 379.7 nm, respectively.

• Analytical Science and Technology
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• v.7 no.2
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• pp.193-199
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• 1994

We have synthesized K-CFICs by the modified two-bulb method. These synthesized compound were analysed with X-ray diffractometer and UV/VIS spectrophotometer. According to X-ray diffraction analysis, the intercalation of potassium between the carbon layers of carbon fiber was better then other intercalants. From obtained data for this deintercalation process, we can see that a number of potassiums were presented as a residue between the carbon layers and this residue compounds had a stability for a long term. Therefore, it is appear that these compounds have a capability as new useful material. From UV/VIS spectrometry data, we can suppose that spectrum of K-CFICs synthesized at $250^{\circ}C$ had only a $R_{min}$, and spectra of any other compounds were not appeared charecteristic peaks because potassium ions were little affect the energy levels of original carbon fiber.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.611-615
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• 2013

Vanadium oxide ($VO_2$) and tungsten-doped vanadium oxide (W-$VO_2$) powder, well known as thermochromic materials, were prepared from vanadium pentoxide ($V_2O_5$) and oxalic acid dihydrate by hydrothermal and calcination process. The crystal structure and thermochromic property of samples were analyzed using FE-SEM, XRD, XPS, DSC, and UV-Vis-NIR spectroscopy. With increasing the doping amount of W, the phase transition temperature of W-$VO_2$ sample decreased from $70^{\circ}C$ to $42^{\circ}C$. When heating W-$VO_2$ sample above the phase transition temperature, the UV-Vis-NIR spectrum was not changed in the visible range and shifted towards a low transparency in the full name (NIR) region.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.5
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• pp.182-187
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• 2005

The FT-IR absorption spectrum by the lattice vibrations of ruby and garnet obtained from FT-IR shows quite different characteristics. By the UV-VIS spectroscopy it was found that the ruby has two transmission bands in red and blue region, while garnet has only one transmission band in red region. The color filter to distinguish ruby from garnet was developed and named HWANG JI HO filter. Through the HWANG JI HO filter, ruby was shown in blue color and garnet was shown in dark red color because of the only the blue region transmittance of the filter. Other red stones, such as spinel, tourmaline were shown in dark red color like as garnet. The ruby could be recognized easily from the red stone.