• Title/Summary/Keyword: SB계수

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Physical Properties of Recycled Sidewalk Pavement Using Wood Chip (Wood Chip을 사용한 자원순환형 보도 포장체의 물성에 관한 연구)

  • Yu, Hyeok-Jin;Choi, Jae-Jin
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.2
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    • pp.91-96
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    • 2010
  • The purpose of this study is to find problems about pedestrian road of tourist resort and to make new type of sidewalk pavement with wood chip and binder using urethane resin on the parks and tourist resort. The wood chip pavement has new economics and durability with comfortable texture. Samples of these pavement materials were tested for tensile strength, permeability and ball rebound value. Also, after immersion for 24 hours, tensile strength, samples' thickness and weight were measured and discussed the strength reduction according to the water immersion. Tensile strength experimentation was examined on dry condition and water immersion. The result of examination on dry condition was 1.06MPa and on water immersion was 0.67MPa. The results showed 36.8% decreasing rate of tensile strength. Permeability experiment test based on field permeability method of pavement were conducted as a result, permeability coefficients were in the range of 0.67~0.78mm/s that all exceeds object permeability coefficient. Elasticity experiment was based on elasticity test method of Japan road association. GB coefficient was 21% and SB coefficient was 10%. GB coefficient and SB coefficient increased if fine aggregate were increased.

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Crystallization behavior and thermoelectric properties of p-type $(Bi_{1-X}Sb_X)_2Te_3$ thin films prepared by magnerron sputtering (마그네트론 스퍼터링법으로 제조한 P형 $(Bi_{1-X}Sb_X)_2Te_3$ 박막의 결정성과 열전특성)

  • 연대중;오태성
    • Journal of the Korean Vacuum Society
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    • v.9 no.4
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    • pp.353-359
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    • 2000
  • $(Bi_{0.15}Sb_{0.85})_2Te_3$ and $(Bi_{1-x}Sb_x)_2Te_3$ thermoelectric thin films were prepared by magnetron sputtering process, and their thermoelectric characteristics were investigated with variation of the sputtering condition and the $Sb_2Te_3$ content. The $(Bi_{0.15}Sb_{0.85})_2Te_3$ film, deposited by DC sputtering at $300^{\circ}C$ with rotating the Corning glass substrate at 10 rpm, was fully crystallized to $(Bi,Sb)_2Te_3$ phase with c-axis preferred orientation. This $(Bi_{0.15}Sb_{0.85})_2Te_3$ film exhibited the Seebeck coefficient of 185 $\mu$V/K which was higher than the values of other $(Bi_{0.15}Sb_{0.85})_2Te_3$ films fabricated with different sputtering conditions. With increasing the $Sb_2Te_3$ content, the Seebeck coefficient and electrical resistivity of p-type $(Bi_{1-x}Sb_x)_2Te_3$ (0.77$\leq$x$\leq$1.0) film were lowered. Among p-type $(Bi_{1-x}Sb_x)_2Te_3$ films, a maximum power factor of $0.79{\times}10^{-3}W/K^2-m$ was obtained at (Bi_{0.05}Sb_{0.95})_2Te_3$ composition..

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Electrical and Thermoelectric Properties of $\textrm{SbI}_{3}$-doped 85% $\textrm{Bi}_{2}\textrm{Te}_{3}$-15% $\textrm{Bi}_{2}\textrm{Se}_{3}$ Thermoelectric Semiconductor ($\textrm{SbI}_{3}$를 첨가한 85% $\textrm{Bi}_{2}\textrm{Te}_{3}$-15% $\textrm{Bi}_{2}\textrm{Se}_{3}$ 열반도체의 전기적 특성과 열전 특성)

  • Hyeon, Do-Bin;Hwang, Jong-Seung;O, Tae-Seong;Yu, Byeong-Cheol;Hwang, Chang-Won
    • Korean Journal of Materials Research
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    • v.8 no.5
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    • pp.413-418
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    • 1998
  • Electrical and Thermoelectric Properties of$ SbI_{3}$-doped 85% 85% $BiTe_{2}$$Se_{3}$ 단결정에서 전하 이동에 대한 살란인자는 0.1이었으며, 전자이동도와 정공이동도의 비($\mu_{e}$ /$\mu_{h}$ )는 1.45이었다. $SbI_{3}$의 첨가량이 증가할수록 전자 농도의 증가로 Seebek 계수와 전기비저항이 감소하며, Seebeck 계수와 전기비저항이 최대값을 나타내는 온도가 고온으로 이동하였다. $SbI_{3}$를 첨가한 85%$Bi_{2}$$Te_{3}$단결정에서 성능지수의 최대값은 $SbI_{3}$를 0.1 wt%첨가한 조성에서 $2.0 x 10^{-3}$ K이었다.

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자동차용 마찰재에 사용되는 고체 윤활재($Sb_{2}S_{3}$)와 연마재 (ZrSiO$){4}$)의 상대량에 따른 마찰특성의 변화에 관한 연구

  • Jang, Ho
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1996.04b
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    • pp.30-34
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    • 1996
  • 자동차용 마찰재의 원료로 사용되는 고체 윤활제($Sb_{2}S_{3}$)와 연마재(ZrSiO$){4}$)의 상대량이 다른 3가지의 마찰재를 제조하여 그들의 마찰특성을 자동차용 Brake Dynamometer를 사용하여 연구하였다. 각각의 마찰재에 관하여 자동차 제동시에 나타나는 마찰계수의 변화와 Torque 변화 그리고 시험후의 마찰재와 rotor의 마모량을 측정하였다. 제동특성과 직접 관련 있는 것으로 알려져있는 마찰계수의 안정성은 $Sb_{2}S_{3}$이 상대량이 높을 때 좋은 특성을 나타내었으며, 반면에 ZrSiO$_{4}$의 상대량이 많은 경우에는 마찰계수의 안정성이 저하되었을 뿐 아니라 제동시의 torque 변화량도 증가하여, 자동차의 Judder현상을 해결하는데 좋지않은 경향을 나타내었다. 이는 마찰시에 계면에 형성되는 윤활막의 거동에 의한 현상이며 이때 마찰재 및 상대재의 마모량은 연마재의 양이 증가함에 따라 마모량이 증가 하였다.

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Basic Study on the Characteristics of Wooden Sidewalk Pavement Material using Wood Waste Chip (폐목재 칩을 활용한 목질계 보도포장재의 특성에 대한 기초연구)

  • Choi, Jae Jin;Song, Jin Woo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.3D
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    • pp.413-420
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    • 2011
  • An experiment was conducted to suggest the road pavement material combining wooden chip crushed from little useful roots and branches from logging sites or wood waste from construction sites with urethane resin. For the specimen, the mass ratio of urethane resin to construction wood waste chip/lumber waster chip was set to three different levels of 0.5, 0.75, and 1.0, which was measured, mixed with mixer, and molded; 7 days after, tensile strength test, elasticity test using golf balls and steel balls, permeability coefficient measurement, and flammability test were executed. As the result, the tensile strength of the specimen at the dry state in the air exhibited the range of 0.2-1.1MPa, and there was no change after 7 days of aging. When submerged in water, however, the strength was partially diminished; the diminishing rate was greater for less urethane resin usage, and therefore it appears desirable to set the mass ratio of resin to the wood waste chip over 0.75 to consider the moisture intrusion by precipitation and such. As the result of elasticity test, the GB and SB coefficients of the specimen using wood waste chips and urethane resin were measured to be low at below 20%, exhibiting excellent elasticity as road pavement material. Also, the permeability coefficient was over 0.5mm/sec for specimens of all combinations, exceeding the standard value required after construction for permeable pavement material, and the flammability of wood-type pavement material was evaluated to have no practical issues.

Fabrication Process and Sensing Characteristics of the In-plane Thermoelectric Sensor Consisting of the Evaporated p-type Sb-Te and n-type Bi-Te Thin Films (n형 Bi-Te와 p형 Sb-Te 증착박막으로 구성된 in-plane 열전센서의 형성공정 및 감지특성)

  • Bae, Jae-Man;Kim, Min-Young;Oh, Tae-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.1
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    • pp.33-38
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    • 2012
  • An in-plane thermoelectric sensor was processed on a glass substrate by evaporation of the n-type Bi-Te and p-type Sb-Te thin films, and its sensing characteristics were evaluated. The n-type Bi-Te thins film used to fabricate the inplane sensor exhibited a Seebeck coefficient of -165 ${\mu}V$/K and a power factor of $80{\times}10^{-4}W/K^2-m$. The p-type Sb-Te thin film used to fabricate the in-plane sensor exhibited a Seebeck coefficient of 142 ${\mu}V$/K and a power factor of $51.7{\times}10^{-4}W/K^2-m$. The in-plane thermoelectric sensor consisting of 15 pairs of the n-type Bi-Te and the p-type Sb-Te evaporated thin films exhibited a sensitivity of 2.8 mV/K.

Surface acoustic wave characteristics of $Pb(Sn_{1/2}Sb_{1/2})O_3-PbZrO_3-PbTiO_3$ ceramics ($Pb(Sn_{1/2}Sb_{1/2})O_3-PbZrO_3-PbTiO_3$ 세라믹스의 탄성 표면파 특성)

  • 홍재일;김준한;유주현;강진규;위규진;박창엽
    • Electrical & Electronic Materials
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    • v.4 no.3
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    • pp.220-228
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    • 1991
  • 본 연구에서는 핫프레스법으로 제작된 0.05Pb(Sn$_{1}$2/Sb$_{1}$2/)O$_{3}$-0.60PbZrO$_{3}$-0.35PbTiO$_{3}$+x[wt%]MnO$_{2}$ 세라믹스에 대해 구조적, 전기적 특성 및 탄성 표면파 특성을 조사하였다. x가 0.4인 조성을 1150[.deg.C]에서 45분간 소성한 시편의 경우 탄성표명파의 전기 기계 결합 계수 k$_{s}$ $^{2}$가 2.8[%], 기계적 품질 계수 Q$_{m}$ 이 1976으로 탄성 표면파 소자용 기판으로서 응용 가능함을 보였다.

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Study of Mobility for Radionuclides in Nuclear Facility Sites (원자력 시설물 주변에서의 방사성 오염물 거동 특성 연구)

  • Chang, Seeun;Park, JongKul;Um, Wooyong
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.99-111
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    • 2018
  • In this study three target radionuclides ($^{60}Co$, $^{137}Cs$, and $^{125}Sb$) were reacted with solid samples collected from the nuclear facility sites to investigate their sorption and mobility behaviors for preparing unexpected nuclear accidents. The highest sorption distribution coefficients ($K_{ds}$) of target radionuclides ($^{60}Co=947mL/g$, $^{137}Cs=2105mL/g$, $^{125}Sb=81.3mL/g$) were found in topsoil layer under groundwater condition, and the $K_d$ values of three radionuclides decreased in the order of fractured rock and bedrock samples under the same groundwater condition. High $K_d$ values of $^{60}Co$ in topsoil layer and fracture rock resulted from the clay minerals present, and the $K_d$ values decreased 58-69 % under seawater condition due to high ionic strength. $^{137}Cs$ sorption was controlled by the ion exchange reaction with $K^+$ on flayed edge sites (FES) of mica. The $^{137}Cs$ sorption was the most affected by seawater (89-97 % decrease), while $^{125}Sb$ sorption was not much affected by seawater. As the results of column and batch experiments, the retardation factors (R) of $^{137}Cs$, $^{60}Co$, and $^{125}Sb$ were determined about 5400-7400, 2000-2500, and 250-415, respectively, indicating no significant transport for these radionuclides even in fractured zone with groundwater. These results suggest that even in the case of severe nuclear accident at the nuclear facilities the mobility of released radionuclides ($^{60}Co$, $^{137}Cs$, and $^{125}Sb$) can be significantly retarded by the topsoil layer and fractured rock. In addition, the results of this study will be used for the safety and environmental performance assessment of nuclear facilities.

Efface of Annealing in a Reduction Ambient on Thermoelectric Properties of the $(Bi,Sb)_{2}Te_{3}$ Thin Films Processed by Vacuum Evaporation (환원분위기 열처리가 $(Bi,Sb)_{2}Te_{3}$ 증착박막의 열전특성에 미치는 영향)

  • Kim, Min-Young;Oh, Tae-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.15 no.3
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    • pp.1-8
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    • 2008
  • Effects of annealing process in a reduction ambient on thermoelectric properties of the $(Bi,Sb)_{2}Te_3$ thin films prepared by thermal evaporation have been investigated. With annealing at $300^{\circ}C$ for 2 hrs in a reduction ambient(50% $H_2$+50% Ar), the crystallinity of the $(Bi,Sb)_{2}Te_3$ thin films were substantially improved with remarkable increase in the grain size. Seebeck coefficients of the $(Bi,Sb)_{2}Te_3$ thin films increased from$\sim90{\mu}V/K$ to $\sim180{\mu}V/K$ with annealing in the reduction ambient due to decrease in the hole concentration. Power factors of the $(Bi,Sb)_{2}Te_3$ thin films were remarkably improved for $5\sim16$ times with annealing in the reduction atmosphere. After annealing in the reduction ambient, a $(Bi,Sb)_{2}Te_3$ evaporated film exhibited a maximum power factor of $18.6\times10^{-4}W/K^{2}-m$.

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Synthesis and characterization of thermoelectric Zn1-xAgxSb compounds (열전재료 Zn1-xAgxSb의 제조와 특성)

  • Kim, In-Ki;Oh, Han-Jun;Jang, Kyung-Wook
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.4
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    • pp.162-166
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    • 2017
  • Thermoelectric compounds of $Zn_{1-x}Ag_xSb$ with x = 0~0.2 were prepared by vacuum melting and quenching process and their crystal phases and thermoelectric properties were examined. It was found that free metallic Sb phases were formed in the compound with x = 0.05, leading to increasing the electrical conductivities. The power factors were significantly affected by the electrical conductivity rather than Seebeck coefficient. When x > 0.05, the peak intensities of $Ag_3Sb$ phases in XRD patterns were increased and those of free Sb phases were weakened. These changes of second phases resulted in decreasing the electrical conductivities and the power factors and became more obvious in the compound with x = 0.2.