• Title/Summary/Keyword: $Bi_2S_3$

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Electrical Current Applied Hot Pressing Processing of $Bi_2Te_3$- $Bi_2Se_3$ Thermoelectrics

  • Park, S.C.;D.G.Baik;Hwang, C.W.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.516-518
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    • 1996
  • Bimuth telluride type thermoelectrics are prepared by AC current applied got pressing method. It is possible to minimize the defects arising from the vaporization of Te, because of the very short processing time. The optimum conditions for the got pressing of 95mol% $Bi_2Te_3$-5mol%$Bi_2Se_3$ themoelectrics are sintered at $400^{\circ}C$, for 2min. with 1500 kgf/$cm^2$ from the particle size of 125 to 250 $\mu$m rang of powder. the resulted Z value (figure of merit) was 2.2$\times$10-3deg-1.

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Fabrication and Characterization of BixCel-xO2-x/2 Electrolytes for IT-SOFC (중온형 고체산화물 연료전지BixCel-xO2-x/2 전해질의 제조 및 특성평가)

  • Han, Ju-Hyeng;Lee, In-Sung;Lee, Dokyol
    • Journal of the Korean Ceramic Society
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    • v.42 no.12 s.283
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    • pp.808-815
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    • 2005
  • [ $Bi_xCe_{l-x}O_{2-x/2}$ ](BD C : Bismuth Doped Ceria) powders with x = 0.1, 0.2, and 0.3 were synthesized using the Glycine Nitrate Process (GNP). They were then calcined at $500^{\circ}C$ for 2 hand sintered in a pellet or rod form at 900, 1000 or $1100^{\circ}C$ for 4 h for characterization as the alternative electrolyte material for intermediate temperature solid oxide fuel cells. The BDC powder consisted of a single phase of $CeO_2-Bi_2O_3$ solid solution in the as-synthesized state as well as in the as-calcined state with a mean powder size of 4.5nm in the former state and 6.5 - 10.1nm in the latter. On the contrary, the second phase of $\alpha-Bi_2O_3$ was observed to have been formed in the sinter with its amount increasing roughly with increasing temperature or $Bi_2O_3$ content. The BOC powder was superior in sinterability to other alternative electrolyte materials such as GDC, ScSZ, and LSGM with the minimum sintering temperature for a relative density of $95\%$ or larger as low as $1100^{\circ}C$. The ionic conductivity of BOC increased with $Bi_2O_3$ content and the maximum value of 0.119 S/cm was obtained at $800^{\circ}C$ for $Bi_{0.3}Ce_{0.7}O_{1.85}$.

Dielectric and Piezoelectric Properties of Nonstoichiometric Sr1±xBi2±yTa2O9 and Sr1±xBi2±yNb2O9 Ceramics (비화학양론 Sr1±xBi2±yTa2O9 과 Sr1±xBi2±yNb2O9 세라믹의 유전 및 압전 특성)

  • Cho, J.A.;Park, S.E.;Song, T.K.;Kim, M.H.;Lee, H.S.
    • Korean Journal of Materials Research
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    • v.13 no.6
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    • pp.360-364
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    • 2003
  • $Sr_{l}$ $\pm$x/$Bi_{2}$ $\pm$y/$Ta_2$ $O_{9}$ and $Sr_{l}$ $\pm$$Bi_{x}$ $2\pm$y$Nb_2$$O_{9}$ ceramics were prepared by a solid state reaction method. X-ray diffraction analysis indicated that single-phase of Bi-layered perovskite was obtained. According to Sr/Bi content ratio, Curie temperature( $T_{c}$), electromechanical factor($K_{p}$ ) and mechanical quality factor($Q_{m}$ ) were measured. The Curie temperature of SBN(SBT) rose from $414^{\circ}C$(314$^{\circ}C$) to $494^{\circ}C$(426$^{\circ}C$) when Sr/Bi content ratio was increased. In the case of Sr/Bi content ratio = 0.55/2.3, the maximum value of the mechanical quality factor $Q_{m}$ of SBT and SBN were obtained 3320 and 1010, respectively.

Interfacial Reaction Characteristics of a Bi-20Sb-10Cu-0.3Ni Pb-free Solder Alloy on Cu Pad (Bi-10Cu-20Sb-0.3Ni 고온용 무연 솔더와 Cu와의 계면 반응 특성)

  • Kim, Ju-Hyung;Hyun, Chang-Yong;Lee, Jong-Hyun
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.1
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    • pp.1-7
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    • 2010
  • Interfacial reaction characteristics of a Bi-10Cu-20Sb-0.3Ni Pb-free alloy on Cu pad was investigated by reflow soldering at $430^{\circ}C$. The thickness of interfacial reaction layers with respect to the soldering time was also measured. After the reflow soldering, it was observed that a $(Cu,Ni)_2Sb$, a $Cu_4Sb$ intermetallic layer, and a haze layer, which is consisted of Bi and $Cu_4Sb$ phases, were successively formed at the Bi-10Cu-20Sb-0.3Ni/Cu interface. The total thickness of the reaction layers was found to be linearly increased with increasing of the reflow soldering time up to 120 s. As the added Ni element did not participate in the formation of the thickest $Cu_4Sb$ interfacial layer, suppression of the interfacial growth was not observed.

Thermoelectric Power Generation by Bi Alloy Semiconductors (Bi계화합물 반도체에 의한 열전발전)

  • 박창엽
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.5 no.3
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    • pp.1-8
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    • 1968
  • This thermcelectrie generator devices have been determined for bismuth alloys, Sb2T and AnSb containing small amounts of doping materials. The thermoeleotric matermoelectric power;$\alpha$; resistivity; $\rho$, heatconduction; k, and temperature difference between cold and hot junction was measured. Generator consisting both B T + B S and B T+S T is better efficient than others containing another thermoceuple matarials. Its efficiency is 1.42%.

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A Novel RGB Channel Assimilation for Hyperspectral Image Classification using 3D-Convolutional Neural Network with Bi-Long Short-Term Memory

  • M. Preethi;C. Velayutham;S. Arumugaperumal
    • International Journal of Computer Science & Network Security
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    • v.23 no.3
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    • pp.177-186
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    • 2023
  • Hyperspectral imaging technology is one of the most efficient and fast-growing technologies in recent years. Hyperspectral image (HSI) comprises contiguous spectral bands for every pixel that is used to detect the object with significant accuracy and details. HSI contains high dimensionality of spectral information which is not easy to classify every pixel. To confront the problem, we propose a novel RGB channel Assimilation for classification methods. The color features are extracted by using chromaticity computation. Additionally, this work discusses the classification of hyperspectral image based on Domain Transform Interpolated Convolution Filter (DTICF) and 3D-CNN with Bi-directional-Long Short Term Memory (Bi-LSTM). There are three steps for the proposed techniques: First, HSI data is converted to RGB images with spatial features. Before using the DTICF, the RGB images of HSI and patch of the input image from raw HSI are integrated. Afterward, the pair features of spectral and spatial are excerpted using DTICF from integrated HSI. Those obtained spatial and spectral features are finally given into the designed 3D-CNN with Bi-LSTM framework. In the second step, the excerpted color features are classified by 2D-CNN. The probabilistic classification map of 3D-CNN-Bi-LSTM, and 2D-CNN are fused. In the last step, additionally, Markov Random Field (MRF) is utilized for improving the fused probabilistic classification map efficiently. Based on the experimental results, two different hyperspectral images prove that novel RGB channel assimilation of DTICF-3D-CNN-Bi-LSTM approach is more important and provides good classification results compared to other classification approaches.

A study on the type of Bi(肥) and Su(痩) of Body in 'Yellow Emperior's Nei-Ching' (${\ll}$내경(內徑)${\gg}$을 중심(中心) 한 체형(體型)의 비수(肥痩)에 대(對)한 고찰(考察))

  • Chun, Tae Kang;Hong, Won Sik
    • Journal of Korean Medical classics
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    • v.6
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    • pp.176-188
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    • 1993
  • After studing on the type of Bi(肥) and Su(痩) of Body in 'Yellow Emperior's Nei-Ching', I reached the following conclusions; 1. The specific charactor of bi(肥) and su(痩) were explained in table 1. 2. The specific charactor of gi(脂), ko(膏) and youk(肉) were explaned in table 2. 3. Obserbing the type of bi(肥) and su(痩) by the view of YinYang(陰陽), bi(肥) belongs to Yin(陰) and su(痩) belongs to Yang(陽). Also the each of bi(肥) and su(痩) could obserbed by the view of YinYang(陰陽). The type of su(痩) easily becomes to yanghea(陽虛) because chi(氣) easely becomes to exhaust also easely becomes to yinhea(陰虛) because blood(血) easely becomes to exhaust. So the outer of body is cold, the inner of body is hot. The type of bi(肥) easely causes YinYang(陰陽) to exceed because blood(血) easely becomes to black and turbid(血黑以濁), chi(氣) easely becomes to rough and slow(氣澁以遲). So the outer of body is hot, the iner of body is cold 4. Obserbing the type of bi(肥) and su(痩) by the view of viscera, in view of upper and lower(上下觀點) su(痩) is yang(陽) so heart and lung belongs to su(痩) bi(肥) is yin(陰) so liver and kidney belongs In bi(肥). in view of inner and outer(內外觀點) su(痩) is inner(內) so heart 3I1d liver belongs In su(痩) bi(肥) is outer(外) so lung and kidney belongs to bi(肥). 5. Obserbing the type of bi(肥) and su(痩) by the view of body constitution(體質), partially body constitution was divided into gi(脂), ko(膏) and youk(肉), entirely there was OhtaeinLon(五態人論) and four constitutional medicine(四象醫學) I thing that taeyangin(太陽人) and soyangin(少陽人) belong to su(痩), taeyinin(太陰人) and soyinin(少陰人) belong to bi(肥).

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MOCVD of $Bi_2Te_3$-based thermoelectric materials and their material characteristics (MOCVD법으로 성장된 열전재료용 $Bi_2Te_3$ 박막의 특성)

  • Kim, Jeong-Hun;Jung, Yong-Chul;Suh, Sang-Hee;Ju, Byeong-Kwon;Kim, Jin-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.13-15
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    • 2005
  • The growth of $Bi_2Te_3$ thin films on (001) GaAs substrates by metal organic chemical vapour deposition (MOCVD) is discussed in this paper. The results of surface morphology, electrical and thermoelectrical properties as a function of growth parameters are given. The surface morphologies of $Bi_2Te_3$ films were strong1y dependent on the deposition temperatures. Surface morphologies varied from step-flow growth mode to island coalescence structures depending on deposition temperature. In-plane carrier concentration and electrical Hall mobility were highly dependent on precursor's ratio of Te/Bi and deposition temperature. The high Seebeck coefficient (of $-160{\mu}VK^{-1}$) and good surface morphology of our result is promising for $Bi_2Te_3$ based thermoelectric thin film and two dimensional supperlattice device applications.

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"Over-inlay" block graft and differential morphometry: a novel block graft model to study bone regeneration and host-to-graft interfaces in rats

  • Ghiacci, Giulia;Graiani, Gallia;Ravanetti, Francesca;Lumetti, Simone;Manfredi, Edoardo;Galli, Carlo;Cacchioli, Antonio;Macaluso, Guido Maria;Sala, Roberto
    • Journal of Periodontal and Implant Science
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    • v.46 no.4
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    • pp.220-233
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    • 2016
  • Purpose: The aim of this study was to present new a model that allows the study of the bone healing process, with an emphasis on the biological behavior of different graft-to-host interfaces. A standardized "over-inlay" surgical technique combined with a differential histomorphometric analysis is presented in order to optimize the use of critical-size calvarial defects in pre-clinical testing. Methods: Critical-size defects were created into the parietal bone of 8 male Wistar rats. Deproteinized bovine bone (DBBM) blocks were inserted into the defects, so that part of the block was included within the calvarial thickness and part exceeded the calvarial height (an "over-inlay" graft). All animals were sacrificed at 1 or 3 months. Histomorphometric and immunohistochemical evaluation was carried out within distinct regions of interest (ROIs): the areas adjacent to the native bone (BA), the periosteal area (PA) and the central area (CA). Results: The animals healed without complications. Differential morphometry allowed the examination of the tissue composition within distinct regions: the BA presented consistent amounts of new bone formation (NB), which increased over time ($24.53%{\pm}1.26%$ at 1 month; $37.73%{\pm}0.39%$ at 3 months), thus suggesting that this area makes a substantial contribution toward NB. The PA was mainly composed of fibrous tissue ($71.16%{\pm}8.06%$ and $78.30%{\pm}2.67%$, respectively), while the CA showed high amounts of DBBM at both time points ($78.30%{\pm}2.67%$ and $74.68%{\pm}1.07%$, respectively), demonstrating a slow remodeling process. Blood vessels revealed a progressive migration from the interface with native bone toward the central area of the graft. Osterix-positive cells observed at 1 month within the PA suggested that the periosteum was a source of osteoprogenitor elements. Alkaline phosphatase data on matrix deposition confirmed this observation. Conclusions: The present model allowed for a standardized investigation of distinct graft-to-host interfaces both at vertically augmented and inlay-augmented sites, thus possibly limiting the number of animals required for pre-clinical investigations.