• East Asian mathematical journal
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• 제14권2호
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• pp.249-257
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• 1998

• 광학세계
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• 통권172호
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• pp.14-15
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• 2017

• 한국전기전자재료학회논문지
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• 제28권7호
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• pp.419-423
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• 2015

Sintering, microstructure, thermal conductivity and microwave dielectric properties of xLiF-(1-x)MgO ceramics (x=0.03~0.10 mol) were investigated. The high density was obtained in the specimens of $x{\geq}0.06$, i.e., 0.04 LiF-0.96 MgO in mol, whereas the amount of 0.03 mol LiF was insufficient to densify. From the result that the contact flattening in the sintered specimen was observed, the densification occurred through the liquid-phase sintering. The specimen of x=0.06 showed the highest room-temperature thermal conductivity. Relative density, thermal conductivity, dielectric constant, and quality factor ($Q{\times}f$) of the specimen for x=0.06 sintered at $900^{\circ}C$ for 4 h were 97.8%, $39.2Wm^{-1}K^{-1}$, 9.45, and 14,671 GHz, respectively.

• Macromolecular Research
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• 제14권6호
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• pp.624-629
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• 2006

The cellulose-based, Electroactive Paper (EAPap) has recently been reported as a smart material with the advantages of lightweight, dry condition, biodegradability, sustainability, large displacement output and low actuation voltage. However, it requires high humidity.. This paper introduces an EAPap made with a cellulose solution and lithium chloride (LiCl), which can be actuated in room humidity condition. The fabrication process, performance test and effect of LiCl content of the EAPap actuator are illustrated. The bending displacement of the EAPap actuators was evaluated with actuation voltage, frequency, humidity and LiCl content changes. At a LiCl/ cellulose content of 3:10, the displacement output was maximized at a room humidity condition. Even though the displacement output was less than that of a high humidity EAPap actuator, the mechanical power output was not reduced due to the increased resonance frequency, which is promising for developing EAPap actuators that are less sensitive to humidity.

• 마이크로전자및패키징학회지
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• 제3권2호
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• pp.27-38
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• 1996

Lithium fluorhectorite 결정상을 함유한 glass ceramics 분말의 형성과 제조된 glass ceramics 분말을 이용한 저온 소결기판의 특성평가를 하였다. Li2O-MgO-MgF2-SiO2 계 유 리로 핵형성 및 결정 성장을 실시하여 lithium fluorhectorite 결정상을 지닌 glass ceramics 를 제조하였다. 유리시편의 핵형성 온도는 46$0^{\circ}C$였고 결정성장온도는 600, 640, 110$0^{\circ}C$에서 나타났다. $600^{\circ}C$에서의 결정상으 Li2.4LiSi4O10F2가 나타났다. Li2.4Mg8LiSi4와 Li2.8Mg0.6SiO4은 lithium fluorhectorite 결정상으로 되기 위한 중간상임을 확인할수 있었다. 64$0^{\circ}C$에서 열처리 후 110$0^{\circ}C$에서 재열처리하여 형성된 결정은 lithium fluorhectorite 와 tridymite가 최종 결정 상으로 나타났다. 이것은 수중에서 water swelling 현상에 의하여 분말화할 수 있었다, 기판 제조용 slurry를 제조하기 위해 glass ceramics 분말에 Al2O3분말을 0,25,50wt%로 혼합한것 과 glass ceramics 분말에 potashborosilica-te glass 분말을 15, 30, 45, 60 wt% 로 배합하 여 doctor blade 법으로 green sheet를 제조하였다. green sheet 는 950~150$0^{\circ}C$로소성하여 기판의 특성을 평가하였다. 겉보기 기공율은 3.06~19,14%이었고, 전기적 특성으로 유전상수 는 3~5(100KHz)를 나타내었다.

• KSBB Journal
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• 제17권1호
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• pp.14-19
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• 2002

본 연구의 목적은 회전생물반응기에 고정화한 P. chrysosporium IFO 31249를 이용하여 LiP 생산의 최적 조건을 조사하는 것이다. 회전생물반응기에서 batch culture시 최대 LiP 활성도는 300 U/L이었다. LiP 생산의 최적 조건은 드림의 회전 속도는 1 rpm, 담체 충진율은 20%이었다. MnP 생산을 위한 $MnSO_4$$\cdot$$H_2O$ 의 최적 농도는 50 ppm이었다. 그리고 산소의 충분한 공급은 LiP 생산의 가장 중요한 인자이었다. 또한 LiP 및 MnP의 생산에 있어 repeated-batch culture가 3번이나 가능하였다.

• 한국수소및신에너지학회논문집
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• 제14권2호
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• pp.122-130
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• 2003

Li/S 이차전지의 유황양극의 전기전도도를 향상시키고 유황이 충방전시 전해질내로 용출되는 것을 방지하기 위하여 multi-walled carbon nanotubes (MWNTs)를 thermal CVD 방법으로 제조하여 유황양극에 첨가하였다. 실험결과 첫 사이클에서 Li/S 이차전지의 방전용량은 485mAh/g-sulfur이었고, MWNT 첨가 이후에 유황양극의 cycle life와 rate-capability가 향상되는 것을 관찰할 수 있었다. 그러므로 MWNT는 polysulfide를 유황양극에 흡착시키는 동시에 good electric conductor로서 작용한다는 것을 알 수 있었다.

• Journal of Electrochemical Science and Technology
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• 제14권4호
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• pp.320-325
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• 2023

In Li-ion batteries, a thick electrode is advantageous for lowering the inactive current collector portion and obtaining a high energy density. One of the critical failure mechanisms of thick electrodes is inhomogeneous lithiation and delithiation owing to the axial location of the electrode. In this study, it was confirmed that the top layer of the composite electrode contributes more to the charging step owing to the high ionic transport from the electrolyte. A high-loading multilayered electrode containing LiFePO₄ (LFP) and LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) was developed to overcome the inhomogeneous electrochemical reactions in the electrode. The electrode laminated with LFP on the top and NCM811 on the bottom showed superior cyclability compared to the electrode having the reverse stacking order or thoroughly mixed. This improvement is attributed to the structural and interfacial stability of LFP on top of the thick electrode in an electrochemically harsh environment.

• 전자공학회논문지D
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• 제35D권7호
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• pp.109-116
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• 1998

In this work was produced and analyzed a z-cut Ti:LiNbO$_{3}$ optical waveguide which applies for various optical devices.A waveguide channel with a thickness 8 .mu.m and a length 66,000.mu.m and a mach-zehnder interferometer type waveguide were fabricated at a diffusion temperature 1050.deg. C for 6-8hours in a wet $O_{2}$ environment. The resulting Ti:LiNbO$_{3}$ optical waveguide was measured to have a Ti-strip thickness of 950.angs. and low loss. Surfaces and cross-sections of a fabricated waveguide were analysed. The mode pattern anaysis revealed that the waveguide showed a single mode at a 1550nm wavelength. The effective dimension of the waveguide was calculated by measuring a gaussian profile; Wx=10.95.mu. and Wy=9.14.mu.m. a propagation loss, of 0.50dB/cm for a TM mode and 0.45dB/cm for a TE mode, was low enough to be accepatable for optical devices.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.375-378
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• 2000

This paper investigated that resonant frequencies of microstrip patch antenna were tunable when piezoelectric materials were used as the antenna substrates. The resonant frequencies of the microstrip antenna using the piezoelectric substrate, like PZT, LiNbO$_3$ were able to be controlled by applied DC voltage. The frequency variation of the air gap antenna was 29MHz when the voltage variation was 14[kV/cm], and the frequency variation of microstrip patch antenna made of LiNbO$_3$substrate was 29MHz when voltage variation was 6[kV/cm].