• Analytical Science and Technology
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• v.13 no.6
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• pp.759-765
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• 2000

A study on the separation of Zr metal from $LiF-BeF_2-ZrF_4$ (67-27-6 mol%) molten salt was carried out using electrowinning. The decomposition potentials of the $LiF-BeF_2$ (72-28 mol%) and the $LiF-BeF_2-ZrF_4$ (67-27-6 mol%) molten salts were measured to be -1.55 and -1.35 volt, respectively. The Zr separation voltage from the salt were found to be in a range of -1.4 -1.5 volt. As increasing applied current, the deposition of molten salt on a cathode increases but the current efficiency decreases. In addition, the deposition and current efficiency decreases with increasing temperature.

• Nuclear Engineering and Technology
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• v.7 no.3
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• pp.191-198
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• 1975

A study was made on the neutron dosimetry in a mixed gamma-neutron field with LiF thermoluminescent dosimeter. In order to estimate the neutron dose in a mixed field, $^{6}$ LiF and $^{7}$ LiF dosimeters were used for fast and thermal neutron doses. The over-all conversion factors for the effects of dosimeter positions were derived for personnel monitoring and the glow curves of the LiF dosimeters for neutron and gamma-ray doses were also analyzed.

• Nuclear Engineering and Technology
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• v.4 no.3
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• pp.214-222
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• 1972

In the optic,11 grade LiF crystal, the electron traps corresponding to the thermoluminescence(abbreviated to TL) glow peak develop as irradiation dose is increased. Originally the electron trap of the crystal has two levels but as the dose reaches to the order of 10$^4$rontgen, it attains five levels as observed in the TL glow curves. The five trap depths are determined from the glow peak temperatures for two different heating rates, $\theta$=6.6$^{\circ}C$/sec and 3.4$^{\circ}C$/sec. The electron trap depths have the following values E$_1$=0.79 eV, E$_2$=0.93 eV, E$_3$=1.02 eV, E$_4$=1.35 eV, E$_{5}$=1.69eV. The special feature of thermoluminescence of optical grade LiF is that the traps, except E$_1$and E$_2$corresponding to 12$0^{\circ}C$ glow peak and 15$0^{\circ}C$ glow peak for $\theta$=6.6$^{\circ}C$/sec, have severe thermal instability, namely E$_3$, E$_4$and E$_{5}$ levels disappear during bleaching process. These defects in the optical grade LiF crystal seem annealed out during the course of TL measurement. The fresh or long time unused LiF(Mg) crystal shows only two glow peaks at 17$0^{\circ}C$ and 23$0^{\circ}C$ for $\theta$=6.6$^{\circ}C$/sec, but upon sensitization with r-ray irradiation, it converts to the six glow peak state. The four electron traps, E$_1$, E$_2$, E$_3$, and E$_{6}$ created by r-ray irradiation and corresponding to the glow peaks at T=10$0^{\circ}C$ 13$0^{\circ}C$, 15$0^{\circ}C$ and 29$0^{\circ}C$ are stable and not easily annealed out thermally, The sensitization essentially required to LiF(Mg) dosimeter is to give the crystal the stable six levels in the electron trap. In optical grade LiF, the plot between logarithm of total TL output versus logarithm of r-ray dose gives more supra-linear feature than that of LiF(Mg). However, if one takes the height of 12$0^{\circ}C$ glow peak(S=6.6$^{\circ}C$/sec), instead of the total TL output, the curve becomes close to that of LiF(Mg).

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.147-147
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• 2015

The multilayer structure of the organic light emitting diode has merits of improving interfacial characteristics and helping carriers inject into emission layer and transport easier. There are many reports to control hole injection from anode electrode by using transition metal oxide as an anode buffer layer, such as V2O5, MoO3, NiO, and Fe3O4. In this study, we apply thin films of LiF which is usually inserted as a thin buffer layer between electron transport layer(ETL) and cathode, as an anode buffer layer to reduce the hole injection barrier height from ITO. The thickness of LiF as an anode buffer layer is tested from 0 nm to 1.0 nm. As shown in the figure 1 and 2, the luminous efficiency versus current density is improved by LiF anode buffer layer, and the threshold voltage is reduced when LiF buffer layer is increased up to 0.6 nm then the device does not work when LiF thickness is close to 1.0 nm As a result, we can confirm that the thin layer of LiF, about 0.6 nm, as an anode buffer reduces the hole injection barrier height from ITO, and this results the improved luminous efficiency. This study shows that LiF can be used as an anode buffer layer for improved hole injection as well as cathode buffer layer.

• Journal of the Korean Ceramic Society
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• v.37 no.6
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• pp.552-558
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• 2000

LiMn2O4 thin fiolm cathodes for Li-ion secondary battery were fabricated by r.f. magnetron sputtering technique. As-deposited films were amorphous. A spinel structure could not be obtained LiMn2O4 films by in-situ thermal annealing. After post thermal annealing over $700^{\circ}C$ in oxygen atmosphere, LiMn2O4 films prepared above 100 W r.f. power could be crystallized into a spinel structure. The electrochemical property of the LiMn2O4 film cathodes was tested in a Li/1 M LiClO4 in PC/LiMn2O4 cell. From cyclic voltammetry at scan rate of 2mV/sec of 2.5~4.5V, LiMn2O4 electrode prepared by post annealing at 75$0^{\circ}C$ showed good initial capacity. LiMn2O4 electrode prepared by post annealing at 80$0^{\circ}C$ showed the best crycling performance.

• Journal of the Korean Ceramic Society
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• v.33 no.6
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• pp.653-659
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• 1996

• Journal of the Korean Ceramic Society
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• v.31 no.2
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• pp.201-205
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• 1994

Glasses being prepared, measurements and investigations of glass transition temperature and IR edge optical absorption have been performed for the compositions of 56ZrF4-14BaF2-6LaF3-4AlF3-(20-x)NaF-xLiF. Values for transition temperature of these glasses decrease in proportion to increasing LiF mol%(x) in the range of 0

• Analytical Science and Technology
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• v.13 no.6
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• pp.712-721
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• 2000

$LiF-BeF_2-ZrF_4$(63-30-7 mol%) molten salt was dissolved up to 0.02g in 1ml of distilled water at room temperature. $ZrO_2$ oxide made from $ZrF_4$ through pyrohydrolysis was recovered by leaching in distilled water with $LiF-BeF_2-ZrF_4$molten salt including it at room temperature. The crystalline sharpness of recovered $ZrO_2$ oxide was not damaged.

• Journal of the Korean Ceramic Society
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• v.21 no.3
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• pp.271-277
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• 1984

To study interface between crystals grown and molten state in the crusible. Pulling and rotating rate of the shaft were varied in LiF crystal growth by Czochralski method. Lower speed of the pulling and rotating rate increased the degree of convexity in solid-liquid interface and higher speed of the pulling and rotating rate decreased it. Optimum condition of LiF crystal growth obtained as pulling rate was 6.5cm/h when it rotated as 46rpm.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.292.2-292
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• 2001