• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.6 s.336
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• pp.17-22
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• 2005

Organic-inorganic hybrid type thin films are the next generation candidates as low-k materials. SiOC films are analyzed the bonding structure by the red and blue chemical shift using the fourier transform infraredspectra. Conventional chemical shift of organic chemistry is a red shift, but hybrid type SiOC films were observed the red and blue shift. The chemical shift originates from the interaction between the C-H bond and high electronegative atoms, and the blue shift in SiOC films is caused by the porosity due to the increase of the electron rich group such as much methyl radicals. The bonding structures of SiOC films are also divided into the Si-O-C cross-link structure and the Si-O-C cage-link structure due to the chemical shifts. The Si-O-C cross-link structure progressed the adhesion attributed to the C-H bond elongation in the reason of the red shift, and the dielectric constant also decreases.

• Journal of Korean Biological Nursing Science
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• v.22 no.4
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• pp.308-316
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• 2020

Purpose: This study aimed to explore the knowledge and performance of sleep hygiene among nurses with shift work schedules and examine the influence on sleep disturbance. Methods: A total of 199 shift-work nurses from a tertiary hospital were included in the study. To examine the knowledge and performance of sleep hygiene, the participants were asked to respond to a self-reported survey. To assess sleep disturbance, the General Sleep Disturbance Scale was used. Descriptive statistics and multiple linear regression were applied using the SPSS/WIN 21.0 program to analyze the data. Results: Both the knowledge and performance of sleep hygiene among nurses with shift work schedules were measured at a moderate level. Nurses' knowledge and the performance of sleep hygiene was not significantly associated with sleep disturbance, whereas age, experience with shift-working, and perceived health status were significantly associated. Conclusion: Strategies for providing more accurate information and motivating better sleep hygiene would help to enhance sleep hygiene in nurses with shift work schedules. Further studies examining the association of knowledge and the performance of sleep hygiene with sleep disturbances in nurses with shift work schedules are needed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.6
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• pp.514-519
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• 2007

The surfaces of $SiO_2$ films were treated by PMMA diluted solutions, and analyzed the chemical shift from Fourier Transform Infrared Spectrometer. The $SiO_2$ film treated by PMMA diluted solution changed the properties of the surface, and showed the blue and red shift according to the concentration of PMMA. The C-H bond elongation effect due to the high electro-negative atom chlorine showed the red shift, and makes the final material with the cross-link structure. The leakage current was efficiently reduced at the sample No 7 with the red shift, witch depends on the electron deficient group.

• Analytical Science and Technology
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• v.11 no.6
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• pp.413-420
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• 1998

The hydrophobic interaction has been studied on sodium naphthalene derivatives such as sodium 1-naphthaleneacetate (S1NA), sodium 1-naphthalenemalonate (SINM), sodium 2-naphthaleneacetate (S2NA), and sodium 2-naphthalenepropionate (S2NP) in $H_2O$-MeOH mixture solutions and in surfactant solutions. In $H_2O$-MeOH mixture solutions, the hydrophobic interaction was measured, and resulted in the red shift in emission spectra. In cationic surfactant, cetyltrimethylamonium bromide (CTAB) solution, the hydrophobic interaction was also observed by the red shift in absorption and emission spectra.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.1-7
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• 1999

Metal colloidal particles have been prepared by a photo-chemical process in an aqueous solution containing semiconductor nanocrystallites. Metal colloidal particles produced in CdS and AgBr exhibit different absorption spectra. Au particles produced in solution with CdS show typical Au plasmon resonance absorption spectra. On the other hand Ag particles in solution with AgBr shows surface plasmon resonance absorption spectra which are red-shifted, as compared to that of a dispersion of homogeneous Ag colloidal particles in the same host. The extent of red-shift depends on the UV illumination time. This phenomenon is interpreted within the context of effective medium theory for small volume fractions. From the theory, a metal coated particle predicts Ag plasmon resonance, red shifted with respect to 400 nm that would be associated with a silver particle in solution. The absorption peak position is very sensitive to the coating thickness.

• Current Applied Physics
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• v.18 no.12
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• pp.1465-1472
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• 2018

The magnetic and optical properties of Ce-doped ZnO systems have been widely demonstrated, but the effects of different strains of Ce-doped ZnO systems remain unclear. To solve these problems, this study identified the effects of biaxial strain on the electronic structure, absorption spectrum, and magnetic properties of Ce-doped ZnO systems by using a generalized gradient approximation + U (GGA + U) method with plane wave pseudopotential. Under unstrained conditions, the formation energy decreased, the system became stable, and the doping process became easy with the increase in the distances between two Ce atoms. The band gap of the systems with different strains became narrower than that of undoped ZnO without strain, and the absorption spectra showed a red shift. The band gap narrowed, and the red shift became weak with the increase of compressive strain. By contrast, the band gap widened, and the red shift became significant with the increase of tensile strain. The red shift was significant when the tensile strain was 3%. The systems with -1%, 0%, and 1% strains were ferromagnetic. For the first time, the magnetic moment of the system with -1% strain was found to be the largest, and the system showed the greatest beneficial value for diluted magnetic semiconductors. The systems with -3%, -2%, 2%, and 3% strains were non-magnetic, and they had no value for diluted magnetic semiconductors. The ferromagnetism of the system with -1% strain was mainly caused by the hybrid coupling of Ce-4f, Ce-5d, and O-2p orbits. This finding was consistent with Zener's Ruderman-Kittel-Kasuya-Yosida theory. The results can serve as a reference for the design and preparation of new diluted magnetic semiconductors and optical functional materials.

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.1-7
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• 2010

The five new red disperse dyes for unmodified pure polypropylene fibers were synthesized. As a coupling component, a di-n-hexyl substituent was used in common, while various substituents were used for the diazo component. The dye having electron donating group at diazo component showed hypsochromic shift compared to the unsubstituted dye, while the dyes having electron withdrawing groups showed bathochromic shift. Owing to their extreme hydrophobicity caused by the di-n-hexyl substituent, all dyes exhibited very high affinity toward pure polypropylene fibers. Fastness to washing was very good for all dyes and fastness to light was good except two purplish red dyes.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.9-17
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• 1983

The effect of pressures and temperatures on the stabilities of the durene-iodine charge transfer complex have been investigated through ultraviolet spectrophotometric measurements in n-hexane. The stabilities of complexes were measured at 25, 40 and $60^{\circ}C$ under $1{\sim}1600$ bars. The equilibrium constant of the complex was increased with pressure and decreased with temperature raising. The absorption coefficient was increased with both pressure and temperature. Changes of volume, enthalpy, free energy and entropy for the formation of complexes were obtained from the equilibrium constants. The red-shift observed at a higher pressure, the blue-shift at a higher temperature, and the relation between pressure and oscillator strength were discussed by means of thermodynamic functions.

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.405-412
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• 1980

The effect of pressures and temperatures on the stabilities of the mesitylene-iodine charge transfer complex have been investigated through ultraviolet spectrophotometric measurements in n-hexane. The stabilities of complexes were measured at 25, 40 and $60^{\circ}C$ under 1∼1600 bars. The equilibrium constant of the complex was increased with pressure and decreased with temperature raising. The absorption coefficient was increased with both pressure and temperature. Changes of volume, enthalpy, free energy and entropy for the formation of complexes were obtained from the equilibrium constants. The red-shift observed a higher pressure, the blue-shift at a higher temperature and the relation between pressure and oscillator strength were discussed by means of thermodynamic functions.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.513-519
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• 1988

The effect of pressure and temperature on the stabilities of hexamethylbenzene-1,3,5-trinitrobenzene charge transfer complex in carbon tetrachloride has been investigated by spectrophotometric measurements. The absorption spectra of charge transfer complexes were measured at 25, 40, $50^{\circ}C$ under 1, 200, 500, 1000, 1400 bar in this experiments. The equilibrium constants of the complex were increased with pressure and decreased with temperature rising. The absorption coefficients were increased with pressure and temperature. Change of volume, enthalpy, free energy and entropy for the formation of complexes were calculated from the equilibrium constants. The red-shift observed at a higher pressure, the blue-shift at a higher temperature and the relation between pressure and oscillator strength were discussed by means of thermodynamic fuctions.