• Title/Summary/Keyword: Red Shift

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The Study on the Physicochemical Properties of Fluid under High Pressure (1). Effects of Pressure and Temperature on the Pentamethyl Benzene-Iodine Charge Transfer Complex in n-HexaneⅠ

  • Kim, Jeong-Rim;Kwun, Oh-Cheun
    • Bulletin of the Korean Chemical Society
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    • v.6 no.2
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    • pp.74-79
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    • 1985
  • The stabilities of the charge transfer complexes of pentamethyl benzene with iodine in n-hexane have been investigated by UV-spectrophotometric measurements at 25, 40 and 60$^{\circ}C$ up to 1600 bars. The equilibrium constant of the complex formation was increased with pressure while being decreased with temperature raising. Changes of volume, enthalpy, free energy and entropy for the formation of the complexes were obtained from the equilibrium constants. The red-shift at higher pressure, the blue-shift at higher temperature, and the relation between pressure and oscillator strength have been discussed by means of thermodynamic functions. In comparison with the results in the previous studies, the absolute values of ${\Delta}$V at each temperature were increased with the number of methyl groups of polymethyl benzene. However, it can be seen that both ${\Delta}$H and ${\Delta}$S show extreme behaviors in durene near atmospheric pressure but they are negatively increased with the number of methyl groups near 1600 bar. This order of the thermodynamic parameters may be a measure of the relative basicities of polymethyl benzenes toward iodine under each pressure, and these phenomena are explained in terms of a positive inductive effect and a steric hindrance effect of the polymethyl benzene molecule.

Effect of Potassium Promoter on the Adsorption of Carbon Monoxide on Silica Supported Ruthenium

  • Lee, Jo-Woong;Chang, Sei-Hun;Pak, Hyung-Suk;Shin, Kook-Joe;Kim, Myung-Kun;Chung, Won-Il
    • Bulletin of the Korean Chemical Society
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    • v.9 no.3
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    • pp.137-143
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    • 1988
  • We have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported ruthenium with and without potassium coating within the frequency range of 1800-2200 $cm^{-1}$ at various ruthenium concentrations and CO pressures. For the system without potassium coating, three bands were observed in the infrared spectra when CO was adsorbed on both the reduced and oxidized form of supported ruthenium. However, the relative intensities of these three bands were found to have no interdependence. Therefore, we have assigned each of these bands as arising from the CO stretching vibration for carbon monoxide molecules adsorbed on the Ru sites of different nature. On coating with potassium, the 2030 $cm^{-1}$ band observed for the system without potassium coating was found to suffer red shift by 10-30 $cm^{-1}$ and we conclude that this bathochromic shift is caused by enhancement in the capability of back donation of electrons from the metal atom to the antibonding ${\pi}{\ast}$ orbitals of CO due to the presence of potassium.

Electroabsorption modulator-integrated distributed Bragg reflector laser diode for C-band WDM-based networks

  • Oh-Kee Kwon;Chul-Wook Lee;Ki-Soo Kim
    • ETRI Journal
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    • v.45 no.1
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    • pp.163-170
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    • 2023
  • We report an electroabsorption modulator (EAM)-integrated distributed Bragg reflector laser diode (DBR-LD) capable of supporting a high data rate and a wide wavelength tuning. The DBR-LD contains two tuning elements, plasma and heater tunings, both of which are implemented in the DBR section, which have blue-shift and red-shift in the Bragg wavelength through a current injection, respectively. The light created from the DBR-LD is intensity-modulated through the EAM voltage, which is integrated monolithically with the DBRLD using a butt-joint coupling method. The fabricated chip shows a threshold current of approximately 8 mA, tuning range of greater than 30 nm, and static extinction ratio of higher than 20 dB while maintaining a side mode suppression ratio of greater than 40 dB under a window of 1550 nm. To evaluate its modulation properties, the chip was bonded onto a mount including a radiofrequency line and a load resistor showing clear eye openings at data rates of 25 Gb/s nonreturn-to-zero and 50 Gb/s pulse amplitude modulation 4-level, respectively.

The Economic Evaluation of Outpatient-chemotherapy administration model (외래 항암 화학요법 주사실 모델의 적정성 분석)

  • Song, Jung Hup
    • Quality Improvement in Health Care
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    • v.11 no.1
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    • pp.16-30
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    • 2004
  • Background: Although the number of cancer patients increase, the resources for cancer management are not increased. If the outpatient chemotherapy administration room is operated, the shift of patients from inpatient 10 outpatient is occurred. So the capacities for chemotherapy increased and the shifted rooms were occupied with new non-chemotherapy patients. The income of the hospital increased. The purpose of this study was to assess usefulness and cost-effectiveness of the outpatient-chemotherapy adminstration model. Method: There are six beds, two chairs and two nurses and one personnel in the outpatient chemotherapy room. The satisfaction study by patients/family and doctors and the cost analysis over 12 months, by comparing costs of chemotherapy administration at outpatient chemotherapy room with inpatient at ward and inpatient-nonchemotherapy at ward were done. Results: The 97.1 percent of patients/family and the 94.4 percent of doctor who involved chemotherapy were satisfied with outpatient chemotherapy administration. The 91.7% of doctors said there were no differences in treatment outcome between outpatient and inpatient chemotherapy administration. The average number of patients in outpatient chemotherapy room increased from 10.7 to 15.4 but in inpatient from 19.4 to 18.3. The average number of inpatient chemotherapy were not changed related to increase of the average number of outpatient chemotherapy. The profit between outpatient chemotherapy and inpatient chemotherapy administration was 45,344,710 won and the profit between outpatient chemotherapy and non chemotherapy treatment was -185,294,614 won. Conclusion: The outpatient chemotherapy administration model is good for patients/family, doctors and hospital partially. But the hypothesis described above was not correct. The process of cancer patients treatment were from diagnosis and treatment to first administration of chemotherapy. So the shift from inpatient to outpatient was not occurred. In economic aspect, the profit between outpatient chemotherapy and non chemotherapy treatment was in the red. As the level of health care fees was so low, the hospitals hesitate operating the room of outpatient chemotherapy. It is necessary to raise the level of health case fees for outpatient chemotherapy administration.

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2D/3D conversion method using depth map based on haze and relative height cue (실안개와 상대적 높이 단서 기반의 깊이 지도를 이용한 2D/3D 변환 기법)

  • Han, Sung-Ho;Kim, Yo-Sup;Lee, Jong-Yong;Lee, Sang-Hun
    • Journal of Digital Convergence
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    • v.10 no.9
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    • pp.351-356
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    • 2012
  • This paper presents the 2D/3D conversion technique using depth map which is generated based on the haze and relative height cue. In cases that only the conventional haze information is used, errors in image without haze could be generated. To reduce this kind of errors, a new approach is proposed combining the haze information with depth map which is constructed based on the relative height cue. Also the gray scale image from Mean Shift Segmentation is combined with depth map of haze information to sharpen the object's contour lines, upgrading the quality of 3D image. Left and right view images are generated by DIBR(Depth Image Based Rendering) using input image and final depth map. The left and right images are used to generate red-cyan 3D image and the result is verified by measuring PSNR between the depth maps.

COLOR CHANGE WITH CEMENT THICKNESS AND COLOR SHIFT PATTERN OF EACH SHADE ERIES IN GI CEMENT (두께에 따른 GI Cement의 색상 변화 및 각 Shade 내의 색상 변화 추이도)

  • Park, Ki-Yeon;Shin, Dong-Hoo
    • Restorative Dentistry and Endodontics
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    • v.22 no.2
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    • pp.622-636
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    • 1997
  • Glass ionomer cements, which had been developed in 1972, were widely used as an agent for cementation, base, pit and fissure sealant, and esthetic filling material with the advantages of excellent biocompatibility, anti-cariogenic fluoride release. Specimens were made to evaluate the color change of Glass ionomer cement with a newly developed improved Fuji II Le. Specimens for color change study with cement thickness of 1, 2, 3mm were made and those for the study of color shift pattern were made with the assumption that new mid-shade can be made by mixing of equal amount of both shades in 2mm thickness. After 24 hours in a $37^{\circ}C$ incubator, CIELAB color spaces were evaluated with a spectrophotometer. The results were as follows ; 1. All specimens discolored to dark and blue with an increased thickness in all shades (p<0.05). 2. There were significant $a^*$ space (red-green direction) changes in every A, B, C, D shade series except the relationship between 1mm and 2mm thickness groups in B shade series. But the changes were irregular, i.e., each shade series has its own pattern. 3. Each shade series showed its own specific color shift pattern in all $L^*$, $a^*$, $b^*$ spaces. 4. B shade series showed less amont of changes in ${\Delta}{\pm}E$ than those of A and C shade series (p<0.05), but there was no significant difference in ${\Delta}E$ within each shade series.

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The Photoluminescence(PL) Spectroscopy and the Photo-Darkening(PD) Effect of the Amorphous SeGe Thin Films (비정질 SeGe 박막의 PL 특성과 광흑화 효과에 관한 연구)

  • 김진우;이현용;정홍배
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.5
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    • pp.435-440
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    • 2002
  • In this study, we have investigated photo-induced changes of optical energy gap( $E_{OP)}$ and photoluminescence (PL) in amorphous ($\alpha$-) S $e_{100-x}$G $e_{x}$ (x=5, 25 and 33) thin films prepared by conventional thermal evaporation method. In the $\alpha$-S $e_{100-x}$G $e_{x}$ thin film, the $E_{OP}$ is obtained by a linear extrapolation of the ($\alpha$hν)$^{\frac{1}{2}}$ versus hν plot to the energy axis using the optical absorption coefficient ($\alpha$) calculated from the extinction coefficient k measured in the wavelength range of 290~900nm. Although the values of $\Delta$ $E_{OP}$ are very different, all films exhibit photo-induced photo-darkening (PD) effect that is a red shift of $E_{OP}$ . In particular, $\Delta$ $E_{OP}$ in $\alpha$-S $e_{75}$ G $e_{25}$ thin film exhibits the largest value (i, e., $\Delta$ $E^{OP}$ ~40meV for $\alpha$-S $e_{95}$ G $e_{5}$ , $\Delta$ $E_{OP}$ ~200meV for $\alpha$-S $e_{75}$ G $e_{25}$ , $\Delta$ $E_{OP}$ ~130meV for $\alpha$-S $e_{67}$ G $e_{33}$ ). PL spectra in $\alpha$-SeGe by hν$_{HeCd}$ have no-Stokes shift (SS) and show a tendency dependent on both composition and illumination time. We explain the energy-induced phenomena such as the PD and thermal bleaching, the native charged-defect generation and the no-SS PL, etc..the PD and thermal bleaching, the native charged-defect generation and the no-SS PL, etc..tc..

Relationship between Dielectric Constant and Increament of Si-O bond in SiOC Film (SiOC 박막에서 Si-O 결합의 증가와 유전상수의 관계)

  • Oh, Teresa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.11
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    • pp.4468-4472
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    • 2010
  • SiOC films made by the inductively coupled plasma chemical vapor deposition were researched the relationship between the dielectric constant and the chemical shift. SiOC film obtained by plasma method had the main Si-O-C bond with the molecule vibration mode in the range of $930{\sim}1230\;cm^{-1}$ which consists of C-O and Si-O bonds related to the cross link formation according to the dissociation and recombination. The C-O bond originated from the elongation effect by the neighboring highly electron negative oxygen atoms at terminal C-H bond in Si-$CH_3$ of $1270cm^{-1}$. However, the Si-O bond was formed from the second ionic sites recombined after the dissociation of Si-$CH_3$ of $1270cm^{-1}$. The increase of the Si-O bond induced the redshift as the shift of peak in FTIR spectra because of the increase of right shoulder in main bond. These results mean that SiOC films become more stable and stronger than SiOC film with dominant C-O bond. So it was researched that the roughness was also decreased due to the high degree of amorphous structure at SiOC film with the redshift after annealing.

Electronic Photodepletion Spectroscopy of Dibenzo-18-crown-6 with a Potassium Ion

  • Kim, Hwan-Jin;Shin, Won-Jik;Choi, Chang-Min;Lee, Jun-Ho;Kim, Nam-Joon
    • Bulletin of the Korean Chemical Society
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    • v.29 no.10
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    • pp.1973-1976
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    • 2008
  • Electronic photodepletion spectrum of dibenzo-18-crown-6 with a potassium ion ($K^+$-DB18C6) was obtained in the gas phase using electrospray ionization and quadrupole ion-trap reflectron time-of-flight mass spectrometry. The spectrum exhibited rather a broad absorption band at 36350 $cm^{-1}$, which was tentatively assigned as the origin of the S1 band. The photodepletion spectrum of $Cs^+$-DB18C6 was also obtained to elaborate the effects of metal cations on electronic and geometric structures of metal cation-DB18C6 complexes. We found that the S1 band of $Cs^+$-DB18C6 was red-shifted by 180 $cm^{-1}$ from that of $K^+$-DB18C6. With the results of quantum theoretical calculations using the density functional theory, we suggested that the red-shift arose mainly from weaker binding of $Cs^+$ to DB18C6 than that of K+, which resulted from a larger size of $Cs^+$ than that of the cavity in DB18C6.

Photocurrent characteristics of close-packed HgTe nanoparticles in the infrared-wavelength range (적외선 영역에서의 HgTe 나노입자 광전류 특성)

  • Kim, Hyun-Suk;Park, Byung-Jun;Kim, Jin-Hyoung;Lee, Jun-Woo;Kim, Dong-Won;Cho, Kyoung-Ah;Kim, Sang-Sig
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.25-28
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    • 2004
  • Photocurrent spectrum, photoresponse, and I-V measurements were made for close-packed HgTe nanoparticles without organic capping materials to investigate their photocurrent characteristics in the infrared range. In absorption and photoluminescence (PL) spectra taken for the close-packed nanoparticles film, the wavelengths of exciton peaks was red-shifted, compared with organic capped HgTe nanoparticles dispersed in solution. This red-shift is caused by the lessening of the exciton binding energy. The I-V curves and photoresponse for the close-packed nanoparticles film reveal their dark current and fast photoresponse with no current decay, respectively. The observation suggests that the HgTe nanoparticles are a very prospect material applicable for photodetectors in the whole IR range.

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