• Journal of the Korean Magnetic Resonance Society
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• v.9 no.2
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• pp.155-162
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• 2005

The interaction of poly(ethylene glycol)(PEG) with cationic dodecyl trimethyl ammonium bromide (DTAB)micelle was studied with electron spin resonance (ESR) by determining line widths of the ESR spectra and coupling constant of nitrogen($A_N$). The degree of ESR line shape change such as line widths and coupling constant indicated that PEG mixes well with DTAB micelle due to a great hydrophobic interaction with surfactant alkyl chains. This suggests that the PEG can be used as non-ionic surfactant to disperse the exposed oil in the ocean.

• Journal of the Korean Magnetic Resonance Society
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• v.1 no.1
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• pp.59-70
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• 1997

The interaction of poly(ethylene glycol) (PEG) with cationic dodecyl trimethyl ammonium bromide (DTAB) micelle was studied with electron spin resonance (ESR) by determining line widths of ESR spectra and coupling constant of nitrogen(AN). The degree of ESR line shape change such as line widths and coupling constant indicated that PEG mixes well with DTAB micelle due to a great hydrophobic interaction with surfactant alkyl chains. This suggests that the PEG can be used as non-ionic surfactant to disperse the exposed oil in the ocean.

• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.341-353
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• 1974

The electrochemical reduction of triphenylphosphine penylimide in nonaqueous media has been examined by polarography, cyclic voltammetry, controlled-potential coulometry and electron spin resonance spectroscopy. The reduction of triphenylphosphine phenylimide proceeds by a one-electron transfer to form anion radical which undergoes both protonation and a second one-electron reduction followed by cleavage of the phosphorus-nitrogen double bond. Aniline is a major product. The cleavage of a phosphorus-phenyl bond was also observed after reduction of triphenylphosphine oxide which is one of the major products of the chemical reaction which follow the primary process.

• BMB Reports
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• v.29 no.2
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• pp.169-174
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• 1996

Yeast cytochrome c (cyt c) was modified at cysteine-102 with a thiol-specific spin label and its interaction with liposomes containing acidic phospholipids was studied by electron paramagnetic resonance (EPR) spectroscopy. Association of cyt c with liposomes resulted in a significant reduction in the mobility of the spin label and a fraction of cyt c even seemed to be immobilized. Based on a large spectral change upon binding and the proximity of the spin-label to lysine-86 and -87, we propose these two residues to be the potential binding site at neutral pH. The interaction is electrostatic in nature because the spectral changes were reversed by addition of anions. Dissociation of the bound cyt c by anions, however, became less effective as the lipid/protein ratio increased. This suggests a repulsive lateral interaction among the bound cyt c. Unlabeled cyt c molecules added to preformed cyt c-liposome complex displaced the bound (spin labeled) cyt c and the process was competitive and reversible.

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.01a
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• pp.15-15
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• 2002

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2000.01a
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• pp.23-23
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• 2000

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.146-151
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• 2007

Gas phase and particulate phase radicals in mainstream cigarette smoke were determined Electron Spin Resonance(ESR) spectroscopy. The free radicals in particulate phase have been investigated by benzene extract of Cambridge Filter Pad containing the smoke condensate. Spin trapping method in conjunction with ESR was used to investigate free radicals in the gas phase of cigarette smoke. Several analytical experiments were conducted in order to determine the optimal conditions for maximum signal intensities and reproducibility of results. All the tests were optimized and normalized using the University of Kentucky 2R4F reference cigarette. The optimal conditions were 0.6 mL for analysis volume of ESR, $4{\sim}5\;mL$ for collection volume of spin-adducts, and PBN for quantification of free radicals in gas phase. The radical levels of Kentucky 2R4F cigarettes were found $2.18{\times}10^{14}\;spins/cig.$ and $2.10{\times}10^{15}\;spins/cig.$ in gas phase.

• Journal of the Semiconductor & Display Technology
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• v.23 no.3
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• pp.29-34
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• 2024

We investigated the n-type δ-doping activation of the tunneling junctions of Si nanolayers for silicon tandem cell applications. The thin film growth of pn junction with the inclusion of phosphorus monolayer was performed by plasma-enhanced chemical vapor deposition with the implement on 6-inch wafers of p-Si microtextured substrates. The rapid thermal annealing processes with various temperatures were performed to activate the δ-doped layer. The activation was confirmed by the electron spin resonance with Lande factor g=2.006085 for the delocalized conduction electron from the phosphorus δ-doped layer at the magnetic field of 3357.5 Gauss. The tunneling junction shows the Ohmic character at the low voltage and the Schottky character at the high voltage bias.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.308-313
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• 2012

Fresh (raw roots), white (dried), and red (steamed-drid) ginseng samples were gamma-irradiated at 0 to 7 kGy. Electron spin resonance (ESR) technique was used to characterize the irradiation status of the samples, targeting the radiation-induced cellulose radicals after different sample pretreatments. All non-irradiated samples exhibited a single central signal (g=2.006), whose intensity showed significant increase upon irradiation. The ESR spectra from the radiation-induced cellulose radicals, with two side peaks (g=2.0201 and g=1.9851) equally spaced (${\pm}3mT$) from the central signal, were also observed in the irradiated samples. The core sample analyzed after alcoholic-extraction produced the best results for irradiated fresh ginseng samples. In the case of irradiated white and red ginseng samples, the central (natural) and radiation-induced (two-side peaks corresponding to cellulose radical) signal intensities showed little improvement on alcoholic-extraction. The water-washing step minimized the effect of $Mn^{2+}$, but reduced the intensity of side peaks making them difficult to indentify. The effect of different origins was negligible, however harvesting year showed a clear effect on radiation-induced ESR signals.

• Journal of the Korean Magnetics Society
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• v.22 no.3
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• pp.73-78
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• 2012

We calculated the electron spin resonance (ESR) line-profile function. The line-width of single-walled carbon nanotube (SWNT) was studied as a function of the temperature at a frequency of 9.5 GHz in the presence of external electromagnetic radiation. The temperature dependence of the line-widths is obtained with the projection operator method (POM) proposed by Argyres and Sigel. The scattering is little affected in the low-temperature region (T < 200 K). We conclude that the calculation process presented in this method is useful for optical transitions in SWNT.