• Journal of Radiation Protection and Research
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• v.35 no.2
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• pp.77-80
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• 2010

The spectroscopy toolkit has been developed and tested. The toolkit consists of a CsI(Tl)/PIN diode detector, integrated electronics, and a multi.channel.analyzer and its size was 40 cm(width) by 20 cm(length) by 6 cm(high). It is compact, very portable and simpler and cheaper compared to the conventional spectroscopy system. The gamma energy resolutions of the toolkit were 7.9% for the 660 keV of $^{137}Cs$ and 4.9% for 1,332 keV of $^{60}Co$ respectively. The linearity for gamma energies was good. When the energy spectrum of a ceramic sample containing $^{232}Th$ was measured with the spectroscopy toolkit for 20 minutes, there were significant peaks of the heavy metal. These results show that the resolution of the spectroscopy toolkit is sufficient to accumulate a quality spectrum in a few minutes by using weak, encapsulated commercial sources. Furthermore a toolkit experiment that how to measure energy spectra using the toolkit, and how to identify specific isotopes in a pottery piece, could be widely adopted for education and even for more sophisticated and higher level experiments.

• Near Infrared Analysis
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• v.1 no.1
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• pp.37-41
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• 2000

The purpose of this research was to develop a the reflection technique with near infrared (NIR) radiation for estimating soil components. NIR reflectance was scanned at 2nm intervals from 1100 to 2500nm with an InfraAlyzer 500 (Bran & Luebbe Co.). Over 400 soil sample from fields of different crops and land-use over Youngnam and Honam regions were used to obtain mean diffuse reflection of the soil for the calibration and validation of the calibration set in estimating moisture, organic matter (OM) and total nitrogen (T-N) of the soils. Multiple linear regression (MLR) was used to evaluate the correlation of NIR spectroscopy method. Reflection pattern of NIR spectra for finely sized sample (<0.5mm) and coarsely sized soil(<2mm) did not show much difference. The results showed that NIR spectroscopy and coarsely sized soil (<2mm) did not show much difference. The results showed that NIR spectroscopy could be used as a routine soil testing method in estimating OM, moisture, T-N in soil samples simultaneously.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.3101-3101
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• 2001

Near Infrared spectroscopy (NIR) used on human skin measurement was explored in the past decade. Many publications in different journals and magazines discussed the feasibility of the NIR technique for cosmetic product property studies. Based upon the results of pioneers, we have pursued some work of the NIR instrument coupled with a probe module for skin measurement in vivo and vitro. In part I of this paper, the specific Near Infrared spectroscopy instrument stability, human subject conditions and other parameters, which could affect the measurements reproducibility are discussed. Second derivative NIR spectra and Principle Components Analysis (PCA) are utilised for data interpretation. In part II of this paper, the relationship of human skin moisture and ageing, the gender information and finally, the discovery of penetration depth of NIR incident light on skin are reported. A theoretical penetration depth calculation equation is proposed. In part III, the study results of a couple of commercial skin care products effect will be described. The skin lotions were applied on human skin (in vivo) in order to exam the NIR feasibility to monitor the changes of moisture level. The results are consistently positive. From our primary study, it can conclude that the NIR is potentially a very powerful instrument for skin condition diagnostics, either for cosmetic and/or for medication purposes.

• Analytical Science and Technology
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• v.12 no.6
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• pp.509-514
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• 1999

The systematic modification of titanium(IV) isopropoxide with acetic acid as a organic additive was done and identifided by FT-IR, $^1H$, $^{13}C$ NMR and UV-Vis spectroscopy. The structure was cbanged after hydrolysis-condensation reaction and drying process. The hydrolysis-condensation rates of modified Ti alkoxide with acetic acid were investigated by $^1H$ NMR spectroscopy. This modified Ti(IV) alkoxide was less reactive toward hydrolysis-condensation reaction than $Ti(OPr^i)_4$, which can be attributed to the stable ligand structure between Ti alkoxide and ligand. The structural change on obtained from gel powders with heat treatment was also observed by FT-IR spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.173-177
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• 2003

The present work is focused on the preconcentration of nickel and its determination by means of diffuse reflection spectroscopy. The preconcentration of nickel was carried out by sorption on macroporous aminocarboxylic amphoteric resin ANKB-35. Based on this collector, a method to determine nickel in wastes of heat power industry was worked out using solid-phase spectroscopy. The colored surface compound to be determined was obtained by a preceding nickel sorption on the resin and by subsequent treatment of the concentrate obtained with definite amounts of 1-(2-pyridilazo)-2-naphtol (PAN). The Ni calibration curve is linear in the concentration range of 0.5-20.0 mg/L (sample volume is 200.0 mL) and the detection limit is 0.05 mg/L. The presence of $Cu^{2+},\;Fe^{3+},\;Co^{2+}$ ions as well as macrocomponents of natural water $(Na^+,\;K^+,\;Ca^{2+},\;Mg^{2+})$ do not hinder the solid-phase spectroscopy determination of nickel. The nickel determination by diffuse reflection spectroscopy was carried out in model solutions as well as in solutions obtained after the dissolution of wastes of heat power industry.

• Biomedical Science Letters
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• v.11 no.2
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• pp.221-225
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• 2005

To investigate the spectroscopic findings of embolized lesions induced with a fat-emulsion technique with magnetic resonance images (MRI). A fat emulsion was made with 0.1 ml of triolein and 20 ml of normal saline. In 12 cats, the internal carotid artery was infused with the fat emulsion. Contrast-enhanced T1-weighted MRI and multivoxel spectroscopy were obtained at 1 hour, 1 and 4 days, and 1 week after embolization. NAA (N-acetylaspartate), Cr (creatine) and Cho (choline) were evaluated on the spectroscopy. Statitistical analysis wsperformed at the embolized and contralateral normal hemisphere in the integral and amplitude of NAA, Cr and Nho in time course. Also NAA/Cr and Cho/Cr were compared in both hemisphere and in time course. The emboli zed lesions showed contrast enhance ments on Gd-enhanced Tl-weighted i~ages at 1 hour. This contrast enhancement was decreased at day 1, and id not appear agter day 4. In spectroscopy, the embolized hemisphere showed no statistical difference to the normal contralateral side at 1 hour and in time course. NAA/Cr and Cho/Cr were not significantly different in both hemispheres at 1 hour and in time course. Cerebral-fat embolism induced by a triolein emulsion in cats revealed no statistical difference on MR spectroscopy. Triolein-emulsion can be used in the study of blood-brain barrier.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.222-227
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• 2003

Recent advances in room-temperature, visible and near-IR diode laser sources for telecommunication, optical data storage applications are enabling combustion diagnostics system based on diode laser absorption spectroscopy. In contrast to some traditional sampling-based gas-sensing instruments, tunable diode laser absorption spectroscopy system is advantageous because of their non-invasive nature, high sensitivity, fast response time and real-time measurement capability. So, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor system arc now appearing for a variety of applications. The objective of this research is to take advantage of distributed feed-back diode laser and measure the $CO_{2}$ concentration (by using direct absorption and wavelength modulation spectroscopy methods). In addition to survey spectra of $CO_{2}$ bands and spectroscopic parameters between 1565 and 1579 run were computed at temperatures between 296 and 1200 K (by using HITRAN 2000 database). It experimentally found out that the features of direct absorption and wavelength modulation spectroscopy methods.

• Analytical Science and Technology
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• v.9 no.4
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• pp.355-363
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• 1996

The two metabolites, Aaptamine(1) and Demethyl(oxy)aaptamine(2) were isolated from marine Sponge Luffariella sp., collected in October 1992, Manado Bay, Sulawesi in Indonesia showed in vitro activity against KB cancer cell line. Their structures were elucidated by $^1H-$, $^{13}C-NMR$, $^1H-^{13}C$(1 bond) heteronuclear multiple quantum coherence spectroscopy(HMQC), electron ionization mass spectroscopy(EIMS), ultra-violet spectroscopy(UV) and infrared spectroscopy(IR).

• Tribology and Lubricants
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• v.35 no.3
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• pp.151-157
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• 2019

Insulated oil degradation produces charged by-products, such as acids and hydro-peroxides, which tend to reduce the insulating properties of the oil. In this study, UV-vis spectroscopy measurement technology is developed and experimentally compared with other measurement methods, such as the titration method and IR spectroscopy, to validate its ability to monitor the degradation of electrical insulating paper. The degradation characteristics of the insulating paper are appropriately represented through various types of measurement methods, such as the Tan (delta) method, $CO_2$ gas production measurement, the titration method, and IR spectroscopy. The results are demonstrated to be well comparable to a change in the fluorescence emission ratio (FER), which is defined as the shift in fluorescence intensity in the measured wavelength range, and also to the chromatic ratio, which is defined as a color shift to longer wavelength ranges. The results also show that, by using UV-vis spectroscopy, it is possible to detect the degradation of the insulating paper. This study suggests that UV-vis spectroscopy can be applied as an alternative to high-performance liquid chromatography, which is the internationally recognized measurement technology for cellulose paper degradation. The FER detector is also verified to be useful as an effective condition-monitoring device for power transformers.

• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.98-102
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• 2010

Magnolia kobus leaf extract was used for the synthesis of bimetallic Au core-Ag shell nanoparticles. Gold seeds and silver shells were formed by first treating aqueous solution of $HAuCl_4$ and then $AgNO_3$ with the plant leaf extract as reducing agent. UV-visible spectroscopy was monitored as a function of reaction time to follow the formation of bimetallic nanoparticles. The synthesized bimetallic nanoparticles were characterized with transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS), and X-ray photoelectron spectroscopy(XPS). TEM images showed that the bimetallic nanoparticles are a mixture of plate(triangles, pentagons, and hexagons) and spherical structures. The atomic Ag contents of the bimetallic Au/Ag nanoparticles determined from EDS and XPS analysis were 34 and 65 wt%, respectively, suggesting the formation of bimetallic Au core-Ag shell nanostructure. This core-shell type nanostructure is expected to have potential for application in surface enhanced Raman spectroscopy and in the sensitive detection of biomolecules.