• 한국세라믹학회지
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• 제37권3호
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• pp.271-279
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• 2000

5 m/o Yb-doped SrCeO3 proton conductor was prepared by a solid state reaction method and its total electriccal conductivity measured as a function of both oxygen partial pressure and water vapor partial pressure in the temperature range of 500~100$0^{\circ}C$. From the total conductivity have been deconvoluted the partial conductivities of oxide ions, protons, and holes, respectively, on the basis of the defect model proposed. The equilibrium constant of hydrogen-dissolution reaction, proton concentration, and mobilities of oxygen vacancies and protons have subsequently been evaluated. It is verified that SrCe1-xYbxO3 is a mixed conductor of holes, protons and oxide ions and the proton conduction prevails as temperature decreases and water vapor pressure increases. The heat of water dissolution takes a representative value of $\Delta$HoH=-(140$\pm$20) kJ/mol-H2O, but tends to be less negative with increasing temperature. Migration enthalpies of proton and oxygen vacancy are extracted as 0.83$\pm$0.10 eV and 0.81$\pm$0.01 eV, respectively.

• 한국결정성장학회지
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• 제19권1호
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• pp.11-14
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• 2009

Micro-pulling down(${\mu}-PD$)법을 이용하여 직경 2mm, 길이 $15{\sim}25\;mm$의 Zn와 Yb가 첨가된 near-stoichiometric 조성의 $LiNbO_3$ 단결정을 성장하였다. 일정 직경의 매끄럽고 결함이 없는 양질의 단결정임을 확인하였고, 결정 내 첨가된 Zn와 Yb의 조성이 고루 분포되었음을 알 수 있었다. Raman spectra를 통해 나타난 모든 peak은 $LiNbO_3$ power의 peak과 일치함을 알 수 있었고, 이를 통해 Hexagonal 구조의 $LiNbO_3$가 성장되었음을 확인할 수 있었다. Zn의 첨가량 증가에 따른 IR 영역의 투과도 비교를 통해 광손상을 억제에 효과가 있는 Zn 첨가의 역치량이 1 mol%임을 알 수 있었다.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.241-245
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• 2007

[ $(Ba_{0.9-x}Sr_xCa_{0.10})TiO_3$ ] (x=0.33, 0.36) powders were prepared by sol-gel method. $(Ba,Sr,Ca)TiO_3$(BSCT) thick films, undoped and doped with $MnCO_3$ and $Yb_2O_3(0.1{\sim}0.7mol%)$, were fabricated by the screen printing method on the alumina substrate. The coating and drying procedure was repeated 6-times. The Pt bottom electrode was screen printing method on the alumina substrate. These BSCT thick films were annealed at $1420^{\circ}C$ for 2 hr in atmosphere. The upper electrodes were fabricated by screen printing the Ag paste and then firing at $590^{\circ}C$ for 10 min. And then the structured and dielectric properties as a function of the doping amount of $Yb_2O_3$ were studied. As a result of the TG-DTA, exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All BSCT thick films showed XRD patterns of typical cubic peroveskite structure. The average thickness of BSCT thick films was about $70^{\mu}m$. The curie temperature and the dielectric constant decreased with increasing $Yb_2O_3$ doped content and the relative dielectric constant of the specimen, doped with 0.5 mol% $Yb_2O_3$ at BSCT(54/36/10), showed a best value of 5018 at curie temperature.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.71-71
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• 2006

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.104-104
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• 2001

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 추계학술발표회
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• pp.34-34
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• 1997

• 한국광학회:학술대회논문집
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• 한국광학회 2004년도 제15회 정기총회 및 동계학술발표회
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• pp.302-303
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• 2004

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 하계학술발표회
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• pp.42-43
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• 2002

고상 소결법으로 715iO$_2$＋11$Na_2$O＋10CaO＋3Er$_2$O$_3$＋5Yb$_2$O$_3$(all wt%) 조성의 스퍼터용 유리 타겟을 제조하여, RF 마그네트론 스퍼터에 의해 희토류 원소가 첨가된 광증폭기용 다성분계 sodium calcium silicate 유리박막을 제조하였다. 최적의 공정조건을 얻기 위해 RF-power, 공정압력, 기판온도를 변화시키면서 박막을 제조하여 RF-power 150W, 공정압력 4mtorr, 기판온도 50$0^{\circ}C$, 타겟-기판 거리 6cm에서 타겟의 손상이 심하지 않으면서, 1.4$mu extrm{m}$/h의 최고 증착율을 가지는 양질의 박막을 제조하였다. (중략)

• 한국군사과학기술학회지
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• 제21권3호
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• pp.295-305
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• 2018

We present a passively Q-switched monolithic Er:Yb:glass microchip laser developed in our lab. The microchip laser can produce pulses at 1535 nm of the 'eye-safe' wavelengths with the pulse energy of 50 uJ and the pulse width of 4-6 ns. Using the laser we also designed and developed a pulsed Er:Yb:glass microchip laser rangefinder. Expressions for background and signal power, noise, and signal-to-noise ratio are reviewed. A computer simulation was used to optimize laser power, receiver aperture, and preamplifier bandwidth for the efficient system design of the laser rangefinder. Experimental results are presented to compare with the theory.

• 한방안이비인후피부과학회지
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• 제19권2호
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• pp.99-107
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• 2006

Objectives : This experimental study was performed to investigate the effects of the Hominis placenta extracts on skin barrier. Methods : Male hairless mice, average weight 20g, were divided into two groups, intact and treatment group(paired, n=15). Intact group was not applied YB-301(an ointment including Hominis placenta). Treatment group was applied YB-301(an ointment including Hominis placenta) two times a day for 8 days. We observed skin melanin, skin erythema, skin pH, skin humidity, transepidermal water loss. Statistical analysis was performed by using paired sample T-test. Statistical significance was achieved if the probability was less than 5%(p<0.05) or 1%(p <0.01) Results : 1. YB-301(an ointment including Hominis placenta) showed statistically significant effect on skin melamin, skin pH, skin humidity(p<0.05). 2. YB-301(an ointment including Hominis placenta) showed statistically significant inhibitory effect on transepidermal water loss(p<0.01). 3. YB-301(an ointment including Hominis placenta) showed statistically no significant effect on skin erythema(p<0.05). conclusions : YB-301(an ointment including Hominis placenta) was effective m skin melanin, skin pH, skin humidity, transepidermal water loss in our study, so we suggest that Hominis placenta can be used as a ointment ingredient for strengthening the function of skin barrier.