• The Korean Journal of Physiology
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• v.16 no.2
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• pp.165-175
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• 1982

Changes in handling of $Li^+$ by contralateral kidney during acute $Li^+$ loading were investigated immediately after unilateral ureteral obstruction. Carotid artery, jugular vein, renal vein and ureter of experimental animal were catheterized and renal venous flow was shunted to .external jugular vein. In experimental group right ureter was ligated. One to two hours after operation a single shot of LiCl solution (2 mEq/kg) was intravenously injected and then .arterial, renal venous blood and urine samples were taken sequentially for 1 to $1{\frac{1}{2}}$ hours. Urine volume, plasma and urinary concentrations of $Li^+$, $Na^+$ and $K^+$ were measured and urinary excretion of them were calculated. Results obtained were as follows: 1) In experimental group urine volume, urinary excretion of $Na^+$, and $K^+$ by contralateral kidney after unilateral ureteral obstruction were slightly larger than mean value of both kidney in control group. 2) During acute $Li^+$ loading contralateral kidney in experimental group showed limited $K^+$ excretion, but urinary flow and $Na^+$ excretion were comparable to mean value of both kidney in control group. 3) Urinary osmolar concentration in experimental group was much lower than that in control group, and it was maintained at low level even after Li loading. 4) In experimental group plasma$Li^+$ concentration decreased more slowly than in control group after a single shot of LiCl solution. 5) Urinary excretion of $Li^+$ in experimental group was markedly decreased, even lesseer than mean of both kidney in control group. 6) From the above results it was concluded that immediately after unilateral ureteral obstruction contralateral kidney showed normal water and $Na^+$ diuretic response to Li load but urinay $Li^+$ excretion was decreased and reclaimed $Li^+$ to systemic circulation.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1736-1738
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• 2000

ITO/TPD($450{\AA}$)/$Alq_{3}(500{\AA})$/Al:Li($1200{\AA}$) 구조의 유기 LED를 제작하였다. Al과 Al:Li(0.lwt%), Al:Li(1wt%), Al:Li(5wt %) 합금을 음전극으로 증착시켜 소자의 전기적 광학적 특성을 분석하였다. 음전극 내의 Li의 분포를 알아보기 위하여 SIMS(Secondary ion Mass Spectroscopy) depth profiling을 하였다. Al:Li합금에서 Li의 함량이 0.1 wt %에서 5 wt %로 증가함에 따라 소자의 turn-on voltage는 약 3.5 V에서 3 V로 감소하였고, 구동전압도 감소하였다. 200$cd/m^2$의 휘도를 기준으로 Al:Li(0.1wt %) 합금을 사용한 소자의 경우 3.5 lm/W로 발광효율이 최대였다. 증착된 Al:Li(0.1wt%) 합금의 SIMS depth profiling 결과 초기에만 Al:Li이 증착되어 Al:Li/Al의 두 층이 형성되었고, Al:Li 합금층의 두께는 약 120${\AA}$ 이었다.

• Analytical Science and Technology
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• v.9 no.1
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• pp.43-51
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• 1996

We have discussed on the deintercalation process of Li-EaGICs and Li-EGICs synthesized under pressure and temperature by spontaneous oxidation reaction of those compounds based on the results of X-ray diffraction, thermal analysis and electrical specific resistivity analysis. According to the results of the X-ray analysis for the intercalation process, we have found that the stage 1 for Li-EaGICs and Li-EGICs were not completly formed, but their lower stages were formed mainly. And from this results of the deintercalation process, we have found that the deintercalation process did not occur any more after 4 weeks, and the Li-EGDICs have more residual lithium metals than LiEaGDICs between the graphite interlayers. According to the thermal decomposition analysis, Li-two compounds had included very hard exothermic reaction. And we have found that these compounds did not occrurred deintercalation reaction above $400^{\circ}C$. According to the results of the electrical specific resistivity measurements, Li-EGDICs have relatively lower electrical specific resistivity than Li-EaGDICs, and Li-EaGDICs showed a formation of the ideal curve. From these results, we can suggest that Li-EaGDICs have a better properties as an anode material secondary than Li-EGICs.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1459-1461
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• 1997

The microwave dielectric ceramic properties of $CaTiO_3-(Li_{1/2}Nd_{1/2})TiO_3$ were investigated. The solid solution of $CaTiO_3-(Li_{1/2}Nd_{1/2})TiO_3$ had the perovskite structure in the range of all composition. The dielectric constant and temperature coefficient of resonant frequency of solid solution were decreased with the contend of $(Li_{1/2}Nd_{1/2})TiO_3$, whereas, the $Q{\times}f$ value was increased. In the $(1-X)CaTiO_3-X(Li_{1/2}Nd_{1/2})TiO_3$ system, the microwave properties could be controlled by the variation of X, X is weight fraction. Typical value of K=119, $Q{\times}f=2970$ and $TCF=14ppm/^{\circ}C$ were obtained for $0.2CaTiO_3-0.8(Li_{1/2}Nd_{1/2})TiO_3$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.133-133
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• 2009

Phospho-olivine $LiFePO_4$ and $LiTi_{0.1}Fe_{0.9}PO_4$ cathode materials were prepared by the solid-state reaction. To improve conductivity we carried out electrochemical performance of $Ti^{2+}$ doped $LiFePO_4$. The $Ti^{2+}$ doped $LiFePO_4$ started 3.36 V of flat voltage on discharge curve and showed a gentle decline in the curve compared to undoped $LiFePO_4$ without great changes of capacity. And so, we could achieve to improve electrochemical performance as reversible, cycle life. Similarly, $LiFePO_4$ doping with $Ti^{2+}$ was showed the effect of dopant which was obtained the improved discharge capacity as 140 mAh/g and good cycling performance.

• Korean Journal of Optics and Photonics
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• v.4 no.1
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• pp.84-89
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• 1993

Spatial homogenity of Mg (4 mole %):LiNb$O_3$ is investigated by studying the characteristic of Second Harmonic Generation in Mg:LiNb$O_3$ as a function of temperature and DC Electric Field. It is found that the temperaturs at which the intensity of the second harmonic is reduced to the first zero from its maximum for the phase matching condition is shifted linearly to the strength of DC Electric field applied to optic axis of Mg:LiNb$O_3$. From these results, the electro-optic coefficient of Mg:LiNb$O_3$ is estimated to be higher than that of Congruent LiNb$O_3$ by a factor of 1.5.

• Journal of Environmental Science International
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• v.5 no.4
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• pp.535-544
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• 1996

In the development of Molten Carbonate Fuel Cell, one of the serious problems is the dissolution of cathode material. Therefore, the development of the alternative cathode which is stable in molten carbonate is needed. In this research, the licoo, was chosen as alternative cathode material. $LiCoO_2$ powder was synthesized by high temperature calcination method and by citrate sol-gel method. And its structure and physical iharacteristics were analyzed by XRD, 1 R, TCA and porosimeter. The conductivity and solubility of $LiCoO_2$ electrode were also measured. Homogeneous $LiCoO_2$ Powder was obtained by citrate sol-Rel method at 445$^{\circ}C$, however, obtained above 75$0^{\circ}C$ by high temperature calcination method. Homogeneous particle size distribution and fine powder were obtained by the citrate sol-Rel method. $LiCoO_2$ electrode showed higher electric conductivity ($1.7 $\Omega$^{-1}cm^{-1}$) than NiO (0.1 $\Omega$^{-9} cm^{-1}) at $650^{\circ}C$. The solubilities of $LiCoO_2$ electrode in electrolyte were varies 0.6 to 1.0 ppm during 200 hours. So, the solubilities of $LiCoO_2$ were much lower than that of NiO.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.1
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• pp.15-20
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• 2011

[ $^7Li$ ]Magic Angle Spinning (MAS) NMR spectroscopy has been used to study the lithium local environments in $Li_4P_2O_7$ and$LiFePO_4$ materials. The purpose of this study was to know the structure of the solid electrolyte interphase (SEI) in lithium ion cells composed of $LiFePO_4$ as cathode material. $Li_4P_2O_7$ and $LiFePO_4$ were prepared by a solid-state reaction. The $^7Li$ MAS NMR experiments were carried out at variable temperatures in order to observe the local structure changes at the temperatures in $Li_4P_2O_7$ system. The $^7Li$ MAS NMR spectra of in $Li_4P_2O_7$ indicate that the lithium local environments in $Li_4P_2O_7$ were not changed in the temperature range between $27^{\circ}C$ and $97^{\circ}C$ Through this work, we confirmed that the small amount of $Li_4P_2O_7$ less than 5.0 wt% in $LiFePO_4$ could be clearly measured by the $^7Li$ MAS NMR spectroscopy at high spinning rate over than 11 kHz.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.101-106
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• 2016

In this study, we prepared an ionic liquid composite solid polymer electrolyte (PEO-LiTFSI-$Pyr_{14}TFSI$) with poly(ethylen oxide), lithium bis(trifluoromethanesulfonyl)imide, N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide by blending-cross linking process. Although the PEO-LiTFSI-$Pyr_{14}TFSI$ composite solid polymer electrolyte displayed a small peak at 4.4 V, it had high electrochemical oxidation stability up to 5.7 V. Ionic conductivity of the PEO-LiTFSI-$Pyr_{14}TFSI$ composite solid polymer electrolyte increased with increasing temperature from $10^{-6}S\;cm^{-1}$ at $30^{\circ}C$ to $10^{-4}S\;cm^{-1}$ at $70^{\circ}C$. To investigate the electrochemical properties, the PEO-LiTFSI-$Pyr_{14}TFSI$ composite solid polymer electrolyte assembled with $LiFePO_4$ cathode and Li-metal anode. At 0.1 C-rate, the cell delivered $40mAh\;g^{-1}$ for $30^{\circ}C$, $69.8mAh\;g^{-1}$ for $40^{\circ}C$ and $113mAh\;g^{-1}$ for $50^{\circ}C$, respectively. The PEO-LiTFSI-$Pyr_{14}TFSI$ solid polymer electrolyte exhibited good charge-discharge performance in Li/SPE/$LiFePO_4$ cells at $50^{\circ}C$.

• Resources Recycling
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• v.32 no.1
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• pp.42-49
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• 2023

The glass ceramic secondary resource containing Li-Al-Si is used in inductor, fireproof glass, and transparent cookware and accounts for 14% of the total consumption of Li, which is the second most widely used after Li-ion batteries. Therefore, new Li resources should be explored when the demand for Li is exploding, and extensive research on Li recovery is needed. Herein, we recovered Li from fireproof Li-Al-Si glass ceramic, which is a new secondary resource containing Li. The fireproof glass among all Li-Al-Si glass ceramics was used as raw material that contained 1.5% Li, 9.4% Al, and 28.9% Si. The process for recovering Li from the fireproof glass was divided into two parts: (1) calcium salt roasting and (2) water leaching. In calcium salt roasting, a sample of fireproof glass was crushed and ground below 325 mesh. The leaching efficiency was compared based on the presence or absence of heat treatment of the fireproof glass. Moreover, the leaching rates based on the input ratios of calcium salt, Li-Al-Si glass, and ceramics and the leaching process based on calcium salt roasting temperatures were compared. In water leaching, the leaching and recovery rates of Li based on different temperatures, times, solid-liquid ratios, and number of continuous leaching stages were compared. The results revealed that fireproof glass ceramics containing Li-Al-Si should be heat treated to change phase to beta-type spodumene. CaCO₃ salt should be added at a ratio of 6:1 with glass ceramics containing Li-Al-Si, and then leached 4 times or more to achieve a recovery efficiency of Li over 98% from a solution containing 200 mg/L of Li.