• 제목/요약/키워드: Zinc selenide

검색결과 15건 처리시간 0.023초

흰쥐의 소뇌에서 selenium 방법에 의한 아연이 함유된 세포의 확인 (Identification of the Zinc-containing Cells in the Cerebellum of Rat by Selenium Method)

  • 조현욱;최은상
    • Applied Microscopy
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    • 제26권4호
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    • pp.411-420
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    • 1996
  • A zinc-specific method (selenium method) has been employed to identify the zinc-containing cells in the cerebellum of the rats. When rats were allowed to survive 24 hours after the sodium selenite administration, zinc selenide reaction products formed in zinc-containing cellular boutons are retrogradely transported to the somata of those boutons. And the zinc selenide products accumulated in somata of the cells can be rendered visible by silver amplification of developer. Zinc-containing cells identified by the method were Bergmann glial and granule cells. Labeled zinc-containing cells were absent in molecular layer and white matter of the cerebellum. In ultrastructural level, the zinc selenide products were located in lysosomes of somata of the zinc-containing cells.

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Growth and characterization of $Cu_2ZnSnSe_4$ (CZTSe) thin films by sputtering of binary selenides and selenization

  • Munir, Rahim;Jung, Gwang-Sun;Ahn, Byung-Tae
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2012년도 춘계학술발표대회
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    • pp.98.2-98.2
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    • 2012
  • Thin film solar cells are growing up in the market due to their high efficiency and low cost. Especially CdTe and $CuInGaSe_2$ based solar cells are leading the other cells, but due to the limited percentage of the elements present in our earth's crust like Tellurium, Indium and Gallium, the price of the solar cells will increase rapidly. Copper Zinc Tin Sulfide (CZTS) and Copper Zinc Tin Selenide (CZTSe) semiconductor (having a kesterite crystal structure) are getting attention for its solar cell application as the absorber layer. CZTS and CZTSe have almost the same crystal structure with more environmentally friendly elements. Various authors have reported growth and characterization of CZTSe films and solar cells with efficiencies about 3.2% to 8.9%. In this study, a novel method to prepare CZTSe has been proposed based on selenization of stacked Copper Selenide ($Cu_2Se$), Tin Selenide ($SnSe_2$) and Zinc Selenide (Zinc Selenide) in six possible stacking combinations. Depositions were carried out through RF magnetron sputtering. Selenization of all the samples was performed in Close Space Sublimation (CSS) in vacuum at different temperatures for three minutes. Characterization of each sample has been performed in Field Emission SEM, XRD, Raman spectroscopy, EDS and Auger. In this study, the properties and results of $Cu_2ZnSnSe_4$ thin films grown by selenization will be presented.

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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.

Convection in the growth of zinc telluride single crystal by physical vapor transport

  • Kim, Geug-Tae
    • 한국결정성장학회지
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    • 제13권4호
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    • pp.187-198
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    • 2003
  • Zinc selenide (ZnSe) single crystals hold promise for many electro-optics, acousto-optic and green laser generation applications. This material is prepared in closed ampoules by the physical vapor transport (PVT) growth method based on the dissociative sublimation. We investigate the effects of diffusive-convection on the crystal growth rate of ZnSe with a low vapor pressure system in a horizontal configuration. Our results show that for the ratios of partial pressures, s=0.2 and 2.9, the growth rate increases with the Peclet number and the temperature differences between the source and crystal. As the ratio of partial pressures approaches the stoichiometric value of 2, the rate increases. The mass fluk based on one dimensional (1D model) flow for low vapor pressure system fall within the range of the predictions (2D model) obtained by solving the coupled set of conservation equations, which indicates the flow fields would be advective-diffusive. Therefore, the rate and the flow fields are independent of gravity acceleration levels.

수열합성법에 의한 Zinc Selenide 나노 분말 합성 및 미세구조 특성 연구 (Fabrication and Characterization of Nano-Sized ZnSe Powders by Hydrothermal Process)

  • 김미소;홍현선
    • 한국재료학회지
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    • 제27권9호
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    • pp.459-465
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    • 2017
  • Nano-sized Zinc selenide (ZnSe) powder was successfully synthesized using Zn and Se precursors in a hydrothermal process. Temperature for the synthesis was varied from $95^{\circ}C$ to $180^{\circ}C$ to evaluate its influence on the microstructural properties of the synthetic particles. ZnSe powder thus fabricated was characterized using various analytical tools such as SEM, XRD, TEM and UV-Vis methods. Two types of ZnSe particles, that is, the precipitated particle and the colloidal particles, were identified in the analysis. The precipitated particles were around 100 nm in average size, whereas the average size of the colloidal particles was around 20 nm. The precipitated particles made at $150^{\circ}C$ and $180^{\circ}C$ were found to be a single phase of ZnSe; however, an inhomogeneous phase was obtained at the lower synthesis temperature of $95^{\circ}C$, suggesting that the temperature for the synthesis should be over $100^{\circ}C$. The precipitated particles were inactive in the UV-Vis absorption investigation, whereas the colloidal particles showed that absorptions occurred at 380 nm in the UV-Vis spectrum.

Predictions of zinc selenide single crystal growth rate for the micro gravity experiments

  • Kim, Geug-Tae
    • 한국결정성장학회지
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    • 제14권5호
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    • pp.226-232
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    • 2004
  • One predicts the crystal growth rate of ZnSe with a low vapor pressure system in a horizontal configuration based on one dimensional advection-diffusion and two-dimensional diffusion-convection model. The present results show that for the ratios of partial pressures, s = 0.2 and 2.9, the growth rate increases with the temperature differences between the source and crystal. As the ratio of partial pressure approaches the stoichiometric value, s = 2 from s = 1.5 (zinc-deficient case: s < 2) and 2.9 (zinc-rich case: s > 2), the rate increases sharply. For the ranges from 1.5 to 1.999 (zinc-deficient case: s < 2) and from s = 9 to 2.9 (zinc-rich case: s > 2), the rate are slightly varied. From the viewpoint of the order of magnitude, the one-dimensional model for low vapor pressure system falls within the 2D predictions, which indicates the flow fields would be advective-diffusive. For the effects of gravitational accelerations on the rate, the gravitational constants are varied from 1 g to $10^{-6}$ g for $\Delta$T = 50 K and s = 1.5, the rates remain nearly constant, i.e., 211 mg/hr, which indicates Stefan flow is dominant over convection.

랫드 후각점막내 Zinc 이온의 조직화학적 동정 (Histochemical Detection of Ionic Zinc in the Rat Olfactory Mucosa: Zinc Selenium Autometallography ($ZnSe^{AMG}$))

  • 남동우;손원재;김성주;김용국;김수진;유윤조;정영길;조승묵
    • Applied Microscopy
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    • 제33권2호
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    • pp.145-154
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    • 2003
  • 본 연구는 후각점막에 내재하는 zinc의 분포를 형태학적으로 뚜렷이 보여준 예가 없기에 조직화학적으로 염색한 후 광학 및 전자현미경으로 이들의 분포를 기술하고자 하였다. 실험동물로는 성숙한 수컷 랫드(SD 계통)를 사용하였다. 우선 동물은 전신마취시킨 후 만들어진 selenium 용액 $100{\mu}l$를 복강에 주사하였고(i.p 실험군), 다른 방법으로는 selenium 용액 $100{\mu}l$를 비강 깁숙히 플라스틱관을 삽입한 후 Hamilton 주사기로 한 방울씩 떨어뜨렸다(i.n 실험군). 후각점막내 zinc를 조직화학법으로 동정하기 위해서 zinc 특이성이 높은 AMG법(Danscher, 1985)을 이용하였다. 각 실험군의 동물은 주사 후 2시간에 이르러 3% Glutaraldehyde 고정액으로 관류함으로써 희생시켰다. 고정후 비중격을 포함하여 후각부위를 떼어낸 수 $30{\mu}l$ 두께의 관상절편을 만들었다. AMG 반응이 끝나면 toluene blue (TB)로 대조염색하고, 알코올과 자일렌 등을 이용한 탈수과정 및 청명과정을 거쳐 광학현미경하에서 관찰하였다. 전자현미경적 절편을 만들기 위해 전자현미경 관찰을 위한 실험으로 vibratome을 사용하여, $100{\mu}m$ 두께의 가로절편을 만들었고, AMG염색이 끝나면 일반적인 전자현미경적 관찰을 위한 일련의 과정을 거쳐 투과전자현미경하에서 관찰하였다. Selenium 용액을 복강에 투여한 i.p 실험군에서는 $30{\mu}m$ 두께의 후각점막의 상층부와 기저부에서 강한 AMG 반응산물(silver grains)이 관찰되었으나 기저막아래 고유판에서는 전혀 관찰되지 않았다. 반면 selenium 용액을 비강점막에 직접 도포한 i.n 실험군에서는 i.p 실험군과 같이 후각점막에서 강한 AMG 반응이 관찰되었을 뿐만 아니라 이러한 반응이 기저막내 후각실의 주행을 따라 관찰되었다. 투과전자현미경으로 관찰된 후각상피에서는 AMG 과립이 지지세포의 세포 상층부에서 관찰되는 분비과립에 국한되는 소견이며, 이곳에서 관찰된 AMG은 과립(silver grains)은 원형 또는 난원형으로 그 크기는 다양하였다. 반면 세포체 하부에서 관찰된 AMG grains은 주로 용해소체위에서 밀집되어 관찰되었으며, 핵주변부 및 세포사이공간(intercellular space)에서는 AMG grains이 낱개로 구분, 관찰되었다. 한편 i.n 실험군에서 관찰된 후각점막의 전반적인 구조가 손상된 소견을 보였으며, 지지세포의 위쪽에서는 전자밀도가 높고 간상의 crystalloid structure가 다수 관찰되었고, 이들 구조에 다수의 AMG 과립이 붙어 있었다. 본 연구의 결과를 요약하면 랫드 후각점막에 존재하는 zinc는 지지세포의 분비과립과 후각세포의 축삭다발인 후각실에서 관찰되었는데 이는 zinc가 후각기능과 매우 밀접한 관련있음을 시사하며, 이는 향후 후각기능과 zinc의 연관성을 연구하는데 소중한 자료가 될 것으로 믿는다. 또한 본 연구의 결과는 후각점막의 이상으로 나타나는 여러 가지 질환의 병리에서 zinc가 영위하는 신경생물학적 기능을 밝히는데 유용한 기초자료가 될 수 있을 것으로 기대한다.

생쥐 맥락얼기에 분포하는 ZnT3 및 zinc 이온의 조직화학적 동정 (Ultrastructural Localization of ZnT3 and Zinc Ions in the Mouse Choroid Plexus)

  • 김성주;김용국;손원재;김수진;정영길;유윤조;조승묵
    • Applied Microscopy
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    • 제32권4호
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    • pp.377-383
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    • 2002
  • 본 연구는 BALB/c 생쥐 맥악얼기내 ZnT3 및 zinc 이온을 ZnT3 항혈청을 이용한 면역세포화학법(ABC법)과 autometallography ($ZnSe^{AMG}$)로 각각 동정하였다. 저배율에서 맥락얼기내 ZnT3 면역반응은 미약하였으나, 고배율에서는 맥락상피와 맥락조직에 국한된 뚜렷한 면역반응이 관찰되었다. 전자현미경에서 관찰된 ZnT3 면역반응은 주로 맥락상피의 자유면쪽 미세융모 및 막성 소기관에 국한되었던 반면 맥락조직내 모세혈관의 내피세포에서는 면역반응이 전혀 관찰되지 않았다. AMG 염색결과 맥락상피와 맥락조직에서 강한 AMG 과립이 관찰되었으며, 특히 모세혈관의 내피상피에서 가장 많이 AMG 과립이 분포하고 있었다. 맥락상피내 AMG 과립은 주로 다소포체에서 관찰되었으며, 소수는 특정 세포질소기관과 상관없이 사이토졸에 산재해 있었다. 이러한 본 연구의 결과를 바탕으로 저자들은 맥락얼기가 일종의 zinc pool의 역할이 있을 것이며, 최소한 뇌척수액과 뇌실질간에 zinc의 이동에 중요한 역할을 담당할 것으로 믿는다.

Properties and Peculiar Features of Application of Isoelectronically Doped $A^2B^6$ Compound-Based Scintillators

  • Ryzhikov, V.;Starzhinskiy, N.
    • Journal of Radiation Protection and Research
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    • 제30권2호
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    • pp.77-84
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    • 2005
  • The authors submit the data concerning the methods of obtaining semiconductor scintillators on the basis of the zinc chalcogenide crystal doped with impurities (Te, Cd, O, $Me^{III}-metals$ Al, In, etc.). Characteristics of such crystals and mechanisms for the semiconductor scintillator luminescence are described as well. The scintillator luminescence spectra maximums are located within the range 450-640nm, which depends on the method of preparing the scintillator. The luminescence decay time ranges within $0.5-10{\mu}s\;and\;30-150{\mu}s$. The afterglow level is less than 0.01% after $10-20{\mu}s$, and the radiation stability is ${\geq}5{\cdot}10^8$ rad. Thermostability of the output characteristics of new semiconductor scintillators on the basis of zinc selenide is prescribed by thermodynamic stability of the principal associative radiative recombination centers that come into existence due to the crystal lattice inherent imperfections. Certain application fields of the new scintillators are examined taking into account their particular qualities.