• Bulletin of the Korean Chemical Society
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• v.13 no.6
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• pp.650-654
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• 1992

Absorption and fluorescence spectra are reported for four different 1 : 3 $Dy^{3+}$ : ligand systems in aqueous solution under mild alkaline pH conditions. The ligands included in this study are oxidiacetate, dipicolinate, iminodiacetate and methyliminodiacetate. The oscillator strengths for the 4f→4f multiplet-to-multiplet transitions are empirically determined from the absorption spectra and the intensity parameters ${\Omega}_{\lambda}$}(${\lambda}$ = 2, 4, 6) for the systems are also obtained by applying the Judd-Ofelt theorem to the observed oscillator strengths. The values of the intensity parameters for the systems are compared and discussed in terms of ligand structural properties to investigate how the intensity parameters can response to the minor changes in the ligand environment. In addition, the relative oscillator strengths for fluorescence are evaluated and compared to the results obtained from absorption spectra.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.232-237
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• 1995

The absorption spectra of holmium nitrate and erbium nitrate and the difference absorption spectra of their complexes with crown ethers were measured in acetonitrile. The crown ethers used in this study are 12-crown-4 and 15-crown-5. The oscillator strengths for the 4f→4f multiplet-to-multiplet transitions are empirically determined from the absorption spectra in combination with the difference spectra. The intensity parameters Ωλ (λ=2, 4, 6) for the systems are also evaluated by applying the Judd-Ofelt theorem to the observed oscillator strengths. The values of the intensity parameters are compared and discussed to investigate the sensitivity of the intensity parameters to the ligand environment.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.109-117
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• 2010

To enable high-performance computing (HPC) for applications with large datasets using a $Sony^{(R)}$ $PLAYSTATION^{(R)}$ 3 ($PS3^{TM}$) video game console, we configured a hybrid system consisting of a $Windows^{(R)}$ PC and a $PS3^{TM}$. To validate this system, we implemented the real-time multiplet identifier (RTMI) application, which identifies multiplets of microearthquakes in terms of the similarity of their waveforms. The cross-correlation computation, which is a core algorithm of the RTMI application, was optimised for the $PS3^{TM}$ platform, while the rest of the computation, including data input and output remained on the PC. With this configuration, the core part of the algorithm ran 69 times faster than the original program, accelerating total computation speed more than five times. As a result, the system processed up to 2100 total microseismic events, whereas the original implementation had a limit of 400 events. These results indicate that this system enables high-performance computing for large datasets using the $PS3^{TM}$, as long as data transfer time is negligible compared with computation time.

• Publications of The Korean Astronomical Society
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• v.10 no.1
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• pp.127-134
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• 1995

Recent discovery of an Io-related feature in Jupiter's auroral regions prompted us to search for an or multiplet at $1304{\AA}$ in IUE aurora spectra. In three independent IUE spectra taken on January 18, 1981, we found an emission structure at $1304{\AA}$, with a signal-to-noise of about three. If the structure is due to the OI emission, then it is a direct evidence of oxygen ion precipitation, which may originate from Io and Io torus. The emission rates of the $H_2$ band systems and the or multiplet are about 50 kR and 150 R, respectively. We have constructed high resolution model spectra with the estimated emission rates of $H_2$, OI and SI for the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope. The model spectra clearly show the or and SI mulitplets separated from crowded $H_2$ Lyman and Werner band lines, and therefore it is promising to detect the OI and SI multiplets with the GHRS. Given the possibility that the lo-related feature may be caused by ion precipitations from the Io flux tube, it is likely that the OI emission may be detected in the footprint area of the IO flux tube.

• Macromolecular Research
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• v.10 no.6
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• pp.304-310
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• 2002

In a recent study by the same authors using a DMTA (Dynamic Mechanical Thermal Analyzer), it was found that the 4-aminobenzoic arid (ABA) molecules acted as either a neutralizing agent, or a plasticizer, or a filler, depending on the order of mixing of poly(styrene-co-styrenesulfonic acid) (PSSA), ABA, and NaOH. Subsequent to that study, we here pursued the same topic, i.e., the effect of the addition of CsOH (instead of NaOH) and ABA on the morphology of PSSA, but this time, by using a small-angle X-ray scattering (SAXS) technique. In line with the previous results, the present study with the SAXS technique verified that the order of mixing has a significant effect on the morphology of ionomers. In addition, with the SAXS data and the density values of the ionomers, we attempted to calculate both the number of sulfonate ionic groups per multiplet and the size of the multiplet of the ionomer.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.54-59
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• 1992

Spectroscopic measurements and theoretical calculations are performed for the four 1 : 3 Sm(III) : ligand solutions. The ligands included in this study are oxidiacetate, iminodiacetate, methyliminodiacetate and dipicolinate. The oscillator strengths for the $4f{\to}4f$ multiplet-to-multiplet transitions are empirically determined from the absorption spectra. The intensity parameters ${\Omega}_{\lambda}\;({\lambda}=2,\;4,\;6)$ of $Sm^{3+}$(aquo) and ${SmL_3}^{3-}$ complexes are also evaluated by applying the Judd-Ofelt theorem to the observed oscillator strengths. The values of the intensity parameters are compared and discussed in term of structural properties of the complexes. In addition, the fluorescence spectra are reported for the Sm(III) complex systems under mild alkaline condition. The excitation from the $^6H_{5/2}$ ground state to any excited states lying above the emitting energy level $(^4G_{5/2})$ produces four fluorescence bands, following nonradiative transitions from a certain excited state to the $^4G_{5/2}$ state. The ratios of oscillator strengths of ${SmL_3}^{3-}$ complexes to that of $Sm^{3+}$(aquo) are also evaluated from the fluorescence spectra and compared to the results obtained from the absorption bands.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.29-33
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• 2005

To facilitate establishing regulations for irradiated foods, Korean traditional soybean-based fermented powdered doenjang (PD), kanjang (PK), kochujang (PKC) and chungkukjang (PC) were irradiated at 1, 3, 5 and 7 kGy, and subjected to irradiation detection analyses as part of establishing a database for detecting irradiated foods. Photostimulated luminescence (PSL) and electron spin resonance (ESR) were applied as the detection methods. Using PSL analysis, the irradiated PD, PK and PKC could be easily distinguished from the non-irradiated ones, while irradiation of the PC at 5 kGy or higher was detectable. The ESR spectra of the irradiated PD, PK and PKC exhibited symmetrical multiplet lines, which might be induced from the crystalline sugar, whereas, the PC showed a single signal at the paramagnetic centers. The signal intensity increased with incremental increases of irradiation doses distinguishing the irradiated samples from the control. In addition, the peak height also revealed that irradiation induced an increment in the intensity of single and/or multiplet lines of the ESR signals, resulting in clear confirmation of irradiation. Thus, the data from this study could be used as references for detecting irradiated soybean-based fermented powdered sauces.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.423-426
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• 2001

Electron spin resonance (ESR) spectroscopy was used to investigate the effect of irradiation dose on irradiated dried fruits. Dried banana, pineapple and pistachio were irradiated with doses of 0, 0.5, 1, 2 and 5 kGy at room temperature using a Co-60 irradiator. Multiplet ESR signals were observed in irradiated dried banana and pineapple, and singlet ESR signal was observed in irradiated pistachio, while these characteristic signals were not detected in non-irradiated samples. Since the amount of free radicals linearly increased with the applied doses $(0.5{\sim}5\;kGy)$, highly positive correlation coefficients $(R^2=0.9874{\sim}0.9974)$ were obtained between the irradiation doses and the corresponding free radical concentrations. The characteristic ESR signals were observed in irradiated samples even after 40 days of storage at room temperature.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.1-7
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• 1989

The autoxidation products derived from methyl linolenate are isolated and characterized by using thin-layer chromatography, infrared, ultraviolet and nuclear magnetic resonance spectrometries. In addition, the propriety of the application of NMR spectrometry to the analysis of the autoxidation products is examined. Spectroscopic data indicate that the autoxidation of methyl linolenate produces hydroperoxides and trans, cis-substituted diene. The autoxidation products have a predominant cis, trans-conjugated diene system with some trans, trans-configuration. The spectroscopic data of ir, uv, and nmr are very consistent with each other, and further investigation of the multiplet region at $5.83{\sim}6.60ppm$ would be very helpful for the structural elucidation of the autoxidation products.

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.1
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• pp.59-73
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• 2006

Spin-lattice relaxation pathway of $CH_2$ spin system by two dimensional NOESY sequence has been discussed. Two-dimensional spectra governed by dipolar relaxation mechanism were simulated in term of transfer mode, the generalization of conventionally used magnetization mode in one dimension. The transfer matrix directly related to the Redfield relaxation matrix can be constructed by the multiplet of transfer mode. The observable relaxation transfer modes causes to variation of the off-diagonal signal intensity of phase sensitive NOESY spectra from which variable spectral density can be extracted with simple group theoretical calculation. The variation of the J-coupling peak intensity as a function of the mixing time in 2-D spectra for $n-Undecane-5-^{13}C$ and Bromoacetic $2-^{13}C$ acid has been theoretically traced.