• Title/Summary/Keyword: sER

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Photoluminescence Properties of $TlGaS_2:Er^{3+}$ Single Crystal ($TlGaS_2:Er^{3+}$ 단결정의 Photoluminescence 특성 연구)

  • 송호준;윤상현;김화택
    • Journal of the Korean Vacuum Society
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    • v.2 no.3
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    • pp.299-303
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    • 1993
  • Erbium metal을 불순물로서 2mol% 첨가한 TlGaS2:Er3+ 단결정을 수평전기로에서 합성한 ingot를 사용하여 수직 Bridgman 방법으로 성장시켰다. 성장된 결정은 층상으로 이루어진 monoclinic 구조였으며, 10K에서 간접전이형 및 직접전이형 energy band gap은 각각 2.55eV, 2.57eV이었고, Er3+ 이온에 의한 두 개의 불순물 광흡수 peak가 524.9nm와 656.4nm에서 관측되었다. Themally stimulated current(TSC)를 측정하여 0.21eV와 0.38eV의 donor 준위와 0.71eV의 accptor 준위를 구하였다. 10K에서 측정된 photoluminescence(PL) spectrum에서는 632nm와 759nm에서 D-A pair에 의한 broad한 peak와 552, 559, 666, 813, 816, 827nm에서 Er3+ 이온에 의한 sharp한 peak들이 나타났다.

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Preparation and Luminescence Optimization of CeO2:Er/Yb Phosphor Prepared by Spray Pyrolysis (분무열분해법으로 CeO2:Er/Yb 형광체 제조 및 발광특성 최적화)

  • Jung, Kyeong Youl;Park, Jea Hoon;Song, Shin Ae
    • Applied Chemistry for Engineering
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    • v.26 no.3
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    • pp.319-325
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    • 2015
  • Submicron-sized $CeO_2:Er^{3+}/Yb^{3+}$ upconversion phosphor particles were synthesized by spray pyrolysis, and their luminescent properties were characterized by changing the concentration of $Er^{3+}$ and $Yb^{3+}$. $CeO_2:Er^{3+}/Yb^{3+}$ showed an intense green and red emission due to the $^4S_{3/2}$ or $^2H_{11/2}{\rightarrow}^4I_{15/2}$ and $^4F_{9/2}{\rightarrow}^4I_{15/2}$ transition of $Er^{3+}$ ions, respectively. In terms of the emission intensity, the optimal concentrations of Er and Yb were 1.0 % and 2.0%, respectively, and the concentration quenching was found to occur via the dipole-dipole interaction. Upconversion mechanism was discussed by using the dependency of emission intensities on pumping powers and considering the dominant depletion processes of intermediate energy levels for the red and green emission with changing the $Er^{3+}$ concentration. An energy transfer from $Yb^{3+}$ to $Er^{3+}$ in $CeO_2$ host was mainly involved in ground-state absorption (GSA), and non-radiative relaxation from $^4I_{11/2}$ to $^4I_{13/2}$ of $Er^{3+}$ was accelerated by the $Yb^{3+}$ co-doping. As a result, the $Yb^{3+}$ co-doping led to greatly enhance the upconversion intensity with increasing ratios of the red to green emission. Finally, it is revealed that the upconversion emission is achieved by two photon processes in which the linear decay dominates the depletion of intermediate energy levels for green and red emissions for $CeO_2:Er^{3+}/Yb^{3+}$ phosphor.

Association of Genetic Polymorphisms of Estrogen Receptor with Litter Size using PCR-RFLP in Yorkshire Swine (Yorkshire종 돼지에서 PCR-RFLP을 이용한 Estrogen Receptor의 유전적 다형과 산자수간의 관련성)

  • Kim, J.E.;Song, W.C.;Choi, B.D.;Kho, Y.;Park, S.S.;Hong, K.C.
    • Journal of Animal Science and Technology
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    • v.45 no.4
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    • pp.523-528
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    • 2003
  • This study was performed to investigate a possible association of the porcine estrogen receptor(ER) locus with the total number of born(TNB) and number of born alive(NBA) in Yorkshire pigs. Using DNAs extracted from 242 Yorkshire pigs, the ER genotype was determined by PvuII PCR-RFLP. The ER allele frequencies of two types of A and B were 0.39 and 0.61, respectively. The least squares means of the litter size by ER genotype was evaluated. The TNB and NBA were found to be associated with an specific ER allele. The genotype at the porcine ER locus has an application potential for marker-assisted selection for litter size in pigs.

《황앵아(黃鶯兒)》에 관한 서지적 분석

  • Seo, Yeon-Ju
    • 중국학논총
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    • no.61
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    • pp.181-202
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    • 2019
  • Huangying-er黃鶯兒 is regarded as one of Feng Menglong's folk song books such as Guazhi-er掛枝兒, Shange山歌, and Jiazhutao夾竹桃. However, preceding researches criticized Huangying-er as 'a fly in the ointment' for laughing at pitiable female entertainers and harming the spirit of edification. In response, there has not been a detailed research on basic items such as editions, compiler, and written time. Thus, this study tried to shed new light on bibliographic information of Huangying-er. To discuss the bibliographic information of Huangying-er, this study organized and supplemented the 8 editions featuring Huangying-er in Ming Dynasty and Qing Dynasty periods. Most of these editions have signature of 'Fubaizhuren浮白主人' or 'Fubaizhaizhuren浮白齋主人'. After organizing the existing theories, this study came to support the theory claiming that the complier is Feng Menglong himself. Also, in reference to the works related to Huangying-er, this study concluded that Huangying-er was complied before compilation of Guazhi-er and Shange, the middle of the Wanli萬曆 reign period.

Optical Properties of Er-implanted GaN (Er 이온 주입된 GaN의 광학적 특성)

  • Son, Chang-Sik
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.12
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    • pp.1101-1105
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    • 2005
  • We have investigated the optical properties of Erbium (Er)-implanted GaN by photoluminescence (PL). Various doses of Er ion were implanted on GaN epilayers by ion implantation. Visible green emission lines due to inner 4f shell transitions for $Er^{3+}$ were observed from the PL spectrum of Er-implanted GaN. The emission spectrum consists of two narrow green lines at 537 and 558 nm. The green emission lines are identified as $Er^{3+}$ transitions from the $^{5}H_{11/2}$ and $^{4}S_{3/2}$ levels to the $^{4}I_{15/2}$ ground state. The stronger peaks in the case with the dose of $5{\times}10^{14}cm^{-2}$, together with the relatively higher intensity of the $Er^{3+}$ luminescence in the lower doped sample. It implies that some damage remains in the case with the dose of $1{\times}10^{16}cm^{-2}$. The peak positions of emission lines due to inner 4f shell transitions for $Er^{3+}$ do not change with increasing temperature. It indicates that $Er^{3+}$ related emission depends very little on the ambient temperature.

Differential expression of glycoconjugates, estrogen receptor-α, c-fos and c-jun in the vagina of normal and ovariectomized rat (흰쥐 발정주기와 난소절제에 따른 질상피의 glycoconjugates, estrogen receptor-α, c-fos 및 c-jun 분포변화)

  • 최병태;길영기;김강련;김순옥;최영현;이준혁
    • Journal of Life Science
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    • v.12 no.3
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    • pp.317-324
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    • 2002
  • We investigated the compositional changes of glycoconjugates (GCs) and expression of estrogen receptor (ER)-$\alpha$, c-fos and c-jun in the vagina of normal and ovariectomized rats by histochemical and immunohistochemical methods. The mucinous transformation of the superficial layer that occurred from late diestrus to proestrus was accompanied with extensive enrichment of GCs. According to the cyclic changes of the vagina, distinct reactivity patterns such as SBA affinity in the diestrus and Con A affinity in the diestrus and estrus phase was observed. However, weak staining for GCs was detected in the atrophied vaginal epithelium of ovariectomized rats. ER-$\alpha$ immunoreaction was mainly demonstrated in the basal layer of epithelium and estrus cycle-related variation in the number of ER-$\alpha$ immunoreaction were not pronounced. But the stromal cells showing ER-$\alpha$ immunoreaction were abundantly observed from diestrus to estrus phase. The most numerous c-fos immunoreactive cells were observed in the basal and intermediate layer of epithelium and stromal fells from the proestrus to estrus phase and c-jun in the basal layer of epithelium during estrus phase. The c-jun immunoreaction of stromal cells expressed only in the estrus phase. In the ovariectomized rats, a few of ER-$\alpha$, c-fos and c-jun immunoreactive cells were observed in the vaginal epithelium and no immunoreaction were found in the stromal cells. ER-$\alpha$ and c-fos immunoreaction fully expressed in the proestrus coincident with the cell proliferation, mutinous transformation and cornification of vaginal epithelium. These data indicate that vagina epithelium and stromal reals express multiple protein such as ER-$\alpha$, c-fos and c-iun by estrogen that may function in process of cells proliferation and differentiation of vagina epithelium.

Electrorhelological Properties of Monodispersed Submicron-sized Hollow Polyaniline Adipate Suspension

  • Sung, Bo-Hyun;Choi, Ung-Su
    • KSTLE International Journal
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    • v.6 no.1
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    • pp.28-32
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    • 2005
  • The electrorheoloRical (ER) fluids are composed of a colloidal dispersion of polarizable particles in insulating oil, and it's the rheological property changes by the applied electric field. These changed are reversible and occur fast within a fewmilliseconds. The ER properties of the ER fluid such as increment of viscosity and yield stress come from the particle chain structure induced by electric fleld. When formulating the ER fluid for a speciflc application, some requirement must besatisfled, which are high yield stress under electric field, rapid response, and dispersion stability. While this characteristic makes valuable ER fluids in valious industrial applications, their lung term and quiescent application has been limited because ofproblems with particle sedimentation. In an effort to overcome sedimentation problem of ER fluids, the anhydrous ER materials of monodispersed hollow polyaniline (PANI) and adipate derivative respectively with submicron-sized suspension providing wide operating temperature range and other advantage were synthesized in a four-step procedure. The ER fluidswere characterized by FT-lR, TGA, DLS, SEM, and TEM. Stability of the suspensions was examined by an UV spectroscopy.The rheological and electrical properties of the suspension were investigated Couette-type rheometer with a high voltagegenerator, current density, and conductivity. And the behavior of ER suspensions was observed by a video camera attached toan optical microscope under 3kV/mm. The suspensions showed good ER properties, durability, and particle dispersion.

Evaluation of Mechanical Characteristic of Al Alloy for Ship's Welded with Various Welding Techniques (다양한 용접기술을 적용한 선박용 알루미늄합금의 기계적 특성 평가)

  • Kim, Seong-Jong;Jang, Seok-Ki;Han, Min-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.13 no.3
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    • pp.223-228
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    • 2007
  • This paper investigated on mechanical characteristic of Al alloy for ship's welded with various welding techniques such as TIG, MIG welding and welding by robot. The yield strength, tensile strength and elongation in TIG welding present 83.9%, 64.6% and 21.9% compare to those in base metal, respectively. The MIG welding is carried out with welding eletrode of ER5183 and ER5356. The mechanical characteristics in ER5356 are improved at approximately 2-4% for ER5183. The mechanical properties of 5083O in welding by robot are better than those of 5456-H116.

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Thermomechanical Effect on the Water Wet Dental Hard Tissue by the Q-switched Er : YAG Laser

  • Y. H. Kwon;Ky0-han Kim
    • Journal of Biomedical Engineering Research
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    • v.20 no.2
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    • pp.231-236
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    • 1999
  • Understanding the exgenous water induced thermomechanical effect on the dental hard tissue by the Q-switched Er:YAG laser (1-$mutextrm{s}$-long pulse width) has an important impact on the further understanding of the free-running Er:YAG laser (250-$mutextrm{s}$-long pulse width) ablation on the dental gard tissue because one macroscopic effect in the free-running laser is an accumulation of microscopic effects we investigated in this study. The Q-switched Er:YAG laser with exogenous water on the tooth enhanced ablation rate compared to the case of no water on the tooth. The frequency of exogenous-water jet on the tooth has affected the ablation rate in such a way that as we dispensed water drops less frequently we could get more enhanced ablation rate. The amplitude of the recoil pressure depends on the tooth surface conditions such that as surfaces wet, and as the volume of the exogenous water drop increased, the amplitude of the recoil pressure increased also. From this study we realized that the 1 $mutextrm{s}$ long pulsed induced thermomechanical effect provides us useful information for the understanding of the free-running Er:YAG laser induced ablation with exogenous water.

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