• 제목/요약/키워드: Se

검색결과 26,059건 처리시간 0.042초

비정질 AsSeS 박막의 홀로그래픽 데이터 격자형성 (Holographic Grating Formation of Amorphous AsSeS Thin Film)

  • 구용운;이송희;남기현;구상모;정홍배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.447-448
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    • 2008
  • In this paper, we investigated the diffraction grating efficiency on AsSeS and Ag-doped amorphous chalcogenide Ag/AsSeS thin film for used to volume hologram. The film thickness was 0.5um and diffraction efficiency was obtained from (P:P) polarized He-Ne (632.8nm)laser beam on AsSeS and Ag/AsSeS thin films. As a results, diffraction grating was not formed at AsSeS thin film but at Ag-doped AsSeS thin film, diffraction grating was formed well compare with the former.

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Effect of Tributylphosphine for the Solution-Liquid-Solid Synthesis of CdSe Nanowires

  • Jang, Hee Su;Lee, Jin Seok
    • Bulletin of the Korean Chemical Society
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    • 제34권2호
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    • pp.590-594
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    • 2013
  • Semiconductor CdSe nanowires (NWs) can serve as model systems for investigating the physical properties of one-dimensional (1D) nanostructures and have great potential for applications in electronics and photonic nanodevices. With numerous attractions arisen from their physical properties, CdSe NWs have been synthesized by vapor-liquid-solid (VLS) methods, but they have some limitations of high reaction temperature and low production. Here, we synthesized CdSe NWs via the solution-liquid-solid (SLS) mechanisms using bismuth (Bi) covered substrates as a low-melting point catalyst and compared the products after injecting identical amount of Se and different amount of tributylphosphine (TBP). CdSe NWs have similar diameters but longer lengths with decreasing TBP, so we proposed the role of TBP as a solvent and capping agent of Se.

간호학생의 전문직사회화, 자아존중감 및 자기효능감에 대한 종단적 연구 (A Longitudinal Study on Professional Socialization, Self-esteem, and Self-efficacy in Nursing Students)

  • 하나선;최정
    • Perspectives in Nursing Science
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    • 제8권2호
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    • pp.73-85
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    • 2011
  • Purpose: The purpose of this study was to clarify longitudinally the professional socialization (PS), self-esteem (SE1), and self-efficacy (SE2) over time in nursing students. Methods: Using a structured questionnaire, data were collected from the same nursing students in 2008, 2009, and 2010 years. Descriptive statistics and one-way ANOVA test with the SAS package were used for the data analysis. Results: The differences in the PS, SE1, and SE2 over time were not significant in nursing students. However, the differences in decision making over time were significant in nursing students. Conclusion: These results suggest that SE1 and SE2 continuously affected professional socialization over time. Therefore, it is necessary to devise a continuing and long-term strategy, which strengthens SE1 and SE2 in order to improve professional socialization.

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S를 고용한 CuInSe$_2$ 박막의 광학 특성 (Optical proper of S solute CuInSe$_2$ thin film)

  • 김규호;이재춘;김민호;배인호
    • 한국표면공학회지
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    • 제30권2호
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    • pp.136-143
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    • 1997
  • The photvoltaic power system has received considerable attention as the petroleumalterative energies to the environmental problems in the wored scale. $CuLnSe_2$is one ofthe most promising materials for the fabrication of large-area modules and low cost photovoltaic devices. Sulfur solute CuInSe2 thin films were prepared by RF sputtering using powder targer which were previously compacted by powder of $Cu_2Se, \;In_2Se_3, \;Cu_2S, \;and\;In_2S_3$ in various ratios. The results induicated that the sulfur ratio, the(112) texture, and the energy band gap were increased by the increase of the S/(S+Se) that was controlled by stoichiometric compound. The energy band gap can be shifted from 1.04eV to 1.50eV by abjusting the S/(S+Se) ratio, which maich it possible to obtain perfect match to the solar spectrum.

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근적외선 센서를 위한 Ag2Se 나노 입자 합성 및 광전기적 특성 (Synthesis and Optoelectronic Characteristics of Ag2Se Nanoparticle for NIR Sensor Application)

  • 장재원
    • 센서학회지
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    • 제28권4호
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    • pp.266-269
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    • 2019
  • In this study, $Ag_2Se$ nanoparticles were synthesized by employing the colloidal method. The synthesized $Ag_2Se$ nanocrystals were spherical in shape with a diameter of approximately 4 nm and had high crystallinity. These attributes of $Ag_2Se$ nanocrystals were determined through images obtained from a high resolution transmission electron microscope. Thin films comprising the synthesized $Ag_2Se$ nanoparticles had an optical band gap of 1.5 eV. Furthermore, fabricated NIR sensors comprising $Ag_2Se$ nanoparticles exhibited a high detectivity of $5.5{\times}10^9$ Jones (above $1{\times}10^9$) at room temperature, leading to low power consumption

Enhancing the Thermoelectric Properties of Layered Bi2O2Q (Q = S, Se): the Effect of Mixed Chalcogen Net

  • Lee, Wang Ro;Lee, Changhoon
    • Journal of the Korean Physical Society
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    • 제73권11호
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    • pp.1684-1690
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    • 2018
  • The layered semiconductors $Bi_2O_2Q$ (Q = S, Se) consists of $Bi_2O_2$ layers sandwiched by Q square nets. On the basis of density functional theory calculations, we examined the thermoelectric properties of $Bi_2O_2S$, $Bi_2O_2Se$ as well as hypothetical structure of $Bi_2O_2$($S_{0.5}Se_{0.5}$) consisting of mixed chalcogen nets. The thermoelectric power factor of $Bi_2O_2S_{0.5}Se_{0.5}$ is much greater than those of $Bi_2O_2S$ and $Bi_2O_2Se$, suggesting that introducing mixed chalcogen net in $Bi_2O_2Q$ is a possible way of enhancing the thermoelectric property of $Bi_2O_2Q$.

Surface Characterization of Zinc Selenide Thin Films Obtained by RF co-sputtering

  • Lee, Seokhee;Kang, Jisoo;Park, Juyun;Kang, Yong-Cheol
    • 대한화학회지
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    • 제66권5호
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    • pp.341-348
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    • 2022
  • In this work, radio frequency magnetron sputtering was used to deposit zinc selenide thin films on p-type silicon (100) wafers and glass substrates in a high vacuum chamber. Several surface characterization instruments were implemented to study the thin films. X-ray photoelectron spectroscopy results revealed that oxidized Zn bound to Se (Zn-Se) at 1022.7 ± 0.1 eV becomes the dominant oxidized species when Se concentration exceeds 70%. Scanning electron microscopy coupled with energy dispersive spectroscopy showed that incorporating Se in Zn thin films will lead to formation of ZnSe grains on the surface. Contact angle measurements indicated that ZnSe-60 exhibited the lowest total surface free energy value of 24.94 mN/m. Lastly, ultraviolet-visible spectrophotometry and ultraviolet photoelectron spectroscopy data evinced that the energy band gap gradually increases with increasing Se concentration with ZnSe-70 having the highest work function value of 4.91 eV.

rBST, Vitamin E 및 Selenium 투여가 한우 종모우의 정액성상, 혈액성분 및 호르몬 변화에 미치는 효과 III. rBST, Vitamin E 및 Selenium 투여가 한우 종모우의 혈액성분 및 호르몬 농도 변화에 미치는 효과 (Effects of rBST, Vitamin E and Selenium Administration on Semen Characteristics, Blood Chemical Values and Hormone in Hanwoo Sires III. Effects of rBST, Vitamin E and Selenium Administration on Blood Chemical Values and Hormone Concentration of Blood in Hanwoo Sires)

  • 박동헌;양부근;김종복;정희태;박춘근;김정익;이성수;박노형;원유석
    • 한국가축번식학회지
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    • 제24권2호
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    • pp.163-170
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    • 2000
  • 본 연구는 rBST, vitamin E 및 selenium (Se)의 투여가 한우 종모우의 혈액성분 및 호르몬의 농도변화에 미치는 영향을 검토하였다. 1. rBST 투여구, Vit. E 투여구 및 Se 투여가 한우 종모우의 혈액성분에 미치는 효과를 조사한 결과, 혈중 albumin의 함량은 Se 투여구가 대조구, rBST 투여구 및 Vit. E 투여구보다 통계적으로 유의하게 높은 함량을 나타났으며 (P<0.05), 혼합투여구는 여타구 (대조구, rBST 투여구 및 vitamin E 투여구)보다 통계적으로 유의하게 높게 나타났다 (P<0.05). 혈중 BUN (Blood Urea Nitrogen)과 creatinine의 함량은 rBST 투여구가 여타구보다 통계적으로 유의하게 높게 나타났다 (P<0.05). 혈중 total protein 함량은 rBST 투여구, Se 투여구 및 혼합투여구가 대조구보다 통계적으로 유의하게 높은 함량을 나타냈다 (P<0.05). 혈중 calcium, cholesterol, glucose, inorganic phosphoros 의 함량은 투여구간에 차이가 없었다 (P>0.05). 2. rBST, Vit. E 및 Se 투여가 한우 종모우의 혈중내 호르몬의 변화에 미치는 효과를 조사한 결과, 혈중 estradiol의 농도는 Se 투여구와 혼합투여구가 여타구 (대조구, rBST 투여구 및 Vit. E 투여구 )보다 다소 높게 나타났지만 유의차는 인정되지 않았으며 (P>0.05), 혈중 testeserone의 농도는 투여구간에 커다란 차이는 없었다 (P>0.05).

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$CaS_{1-x}Se_x:Eu$ 형광체의 발광 특성 (Photoluminescence properties of $CaS_{1-x}Se_x:Eu$ phosphors)

  • 유은경;허영덕
    • 한국결정성장학회지
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    • 제17권5호
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    • pp.204-209
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    • 2007
  • 형광체-변환 3파장 백색 발광 다이오드(LED)의 응용을 위하여 일련의 $CaS_{1-x}Se_x:Eu$ 형광체를 합성하였다. $CaS_{1-x}Se_x:Eu$의 구조와 발광 특성을 조사하였다. $CaS_{1-x}Se_x:Eu$ 형광체는 청색 발광 다이오드의 발광 파장인 455nm에서 강한 흡수가 있다. $Eu^{2+}$$4f^65d^1(T_{2g}){\rightarrow}4f^7(^8S_{7/2})$ 전이 때문에 CaS:Eu는 651nm에서 적색 발광 봉우리를 가지고 있다. $CaS_{1-x}Se_x:Eu$의 발광 봉우리는 Se이 증가함에 따라서 651nm에서 598nm으로 이동이 된다. $CaS_{1-x}Se_x:Eu$ 형광체는 청색 LED로 여기하면 가변 파장의 적색 발광을 하는 형광체로 사용될 수 있다. $SrGa_2S_4:Eu$$CaS_{0.50}Se_{0.50}:Eu$ 형광체를 청색 발광 다이오드에 도포하여 백색 발광 다이오드를 제작하였다.

$Ag_2CdSnSe_4$$Ag_2CdSnSe_4:Co^{+2}$단결정의 광학적 특성 (Optical properties of $Ag_2CdSnSe_4$ and $Ag_2CdSnSe_4:CO^{2+}$ single crystals)

  • 이충일
    • 한국진공학회지
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    • 제10권1호
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    • pp.16-21
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    • 2001
  • 4원 화합물 반도체인 $Ag_2CdSnSe_4$$Ag_2CdSnSe_4$:$CO^{2+}$ 단결정을 화학수송법으로 성장시켜 광학적 특성을 조사하였다. 성장된 결정들은 wurtzite 결정구조로서 격자상수는 각각 a = 4.357 $\AA$, c = 7.380 $\AA$($Ag_2CdSnSe_4$:$CO^{2+}$)이었다. 298k에서의 광 흡수 측정으로부터 구한 에너지 띠 간격은 순수한 $Ag_2$CdSnSe의 경우 1.21eV, cobalt 불순물로 첨가한 $Ag_2CdSnSe_4$의 경우 1.02ev이었으며, cobalt를 불순물로 첨가함에 따라 190meV의 에너지 띠 간격의 감소를 보였다. $Ag_2CdSnSe_4$ 결정의 광 흡수 스펙트럼에서 4개의 흡수 피크들을 관측하였으며, 이들 피크 들은 $T_d$결정장내에서 스핀 - 궤도결합효과에 의한 $Co^{2+}$ 이온의 분리된 준위사이의 전자전이에 의한 것으로 설명되었다.

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