• Journal of the Korean Electrochemical Society
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• v.13 no.2
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• pp.103-109
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• 2010

$Li_4Mn_5O_{12}$ was synthesized by combustion method using $LiNO_3$, $Li(CH_3COO){\cdot}2H_2O$ and $Mn(CH_3COO)_2{\cdot}4H_2O$. $Li_4Mn_5O_{12}$ was obtained over $400^{\circ}C$, however, the sample calcined at $400^{\circ}C$ for any time was mixed phases of $Li_4Mn_5O_{12}$ and $Mn_2O_3$. $Li_4Mn_5O_{12}$ calcined at $400^{\circ}C$ for 5 h had larger first discharge capacity (41.5mAh/g) at 1C-rate for 3.7~4.4V than other calcined samples. Moreover, applying to hybrid capacitor, it had good discharge capacity (24.74 mAh/g or 10.46 mAh/cc) at 100 mA/g for 1~2.5 V and higher energy density (39Wh/kg or 16.49Wh/cc) at same condition.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.251-264
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• 2019

The displacement monitoring of unstable block at the rock slope located in the Cheonbuldong valley of Seoraksan National Park was carried out using Terrestrial LiDAR. The rock slopes around Guimyeonam and Oryeon waterfall where rockfall has occurred or is expected to occur are selected as the monitoring section. The displacement monitoring of unstable block at the rock slope in the selected area was performed 5 times for about 7 months using Terrestrial LiDAR. As a result of analyzing the displacement based on the Terrestrial LiDAR scanning, the error of displacement was highly influenced by the interpolation of the obstruction section and the difference of plants growth. To minimize the external influences causing the error, the displacement of unstable block should be detected at the real scanning point. As the result of analyzing the displacement of unstable rock at the rock slope using the Terrestrial LiDAR data, the amount of displacement was very small. Because the amount of displacement was less than the range of error, it was difficult to judge the actual displacement occurred. Meanwhile, it is important to select a section without vegetation to monitor the precise displacement of unstable rock at the rock slope using Terrestrial LiDAR. Also, the PointCloud removal and the mesh model analysis in a vegetation section were the most important work to secure reliability of data.

• Journal of Haehwa Medicine
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• v.10 no.1
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• pp.269-286
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• 2001

Objectives : This Investigation was aimed to find out the Classification of Cause and the Effect of Acupuncture and Moxibustion Treatment for Dentalgia Methods : We surveyed the oriental medical books from $\ll$HungTiNeiChing$\gg$ to recent published books concerning the Acupuncture therapy for Dentalgia Results : 1. Since the time of $\ll$HungTiNeiChing$\gg$ there was called "yateng", "yatong", "chiyaqutong", "kouchitong", "nichi", "chichong", "fengchi", "chongshitong", "chongshiyachi", "chifengzhongtong", "chiyinzhong", "yachuangzhongtong" 2. The Oriental Medical cause of Dentalgia are fire, wind, cold, blood stasis, stomach-heat, phlegm, difficiency of kidney, late snack, insect and wound, and then the Western Medical cause are cacodontia, periodontal disease, trigeminal nerve pain, stress 3. The meridians used for the treatment are large intestine, stomach, triple warmer, gallbladder and small intestine 4. The most frequently used acupuncture point for the treatment are Hapkok(LI3), Naejong(S44), Hyopko(S6), Igan(LI2), Sohae(H3), Yanggok(SI5), Hagan(S7), Taeyong(S5), Samgan(LI3), Kokehi(LI11) 5. The most frequently used moxibustion for the treatment are Sungjang(CV24), Yolgyol(L7), Kyonu(LI15), Taeyon(L9), Hapkok(LI3) 6. In the superior dental pain there commonly used the acupuncture point of stomach meridian, triple warmer meridian, gallbladder meridian in the inferior dental pain there commonly used the acupuncture point of large intestine meridian. 7. The most frequently used acupuncture point for the superior dental pain are Naejong(ST44), Yanggok(SI5), Chongnyong(G17), Kakson(TE20), In the inferior detal pain there are Taeyong(S5), Hapkok(LI3), Igan(LI2), Sangyang(LI1), Samgan(LI3) 8. In the treatment of dental pain The Acupuncture therapy utilized the division of region are the Erzhen therapy(耳針療法), the Touzhen therapy(頭鍼療法), the Shouzhen therapy(手鍼療法), the Zuzhen therapy(足鍼療法), the Bizhen therapy(鼻針療法), the Wanhuaizhen therapy 9. In dental pain the other therapy are the Taozhen therapy(陶鍼療法), the Pifuzhen therapy(皮膚針療法), the Dianzhen therapy(電鍼療法), the Yaozhen therapy(藥針療法).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.2
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• pp.196-206
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• 1995

Experimental investigations on heat and mass transfer characteristics in a vertical tube absorber have been carried out. Three different copper tubes with a length of 1.5m have been tested using LiBr solution and LiBr-$CaCl_2$ solution. The effects of solution flow rate, cooling water temperature, solution inlet temperature and evaporation temperature have been investigated in detail. It is found that heat transfer coefficient increases gradually with the increase of solution flow rate, but decreases rapidly for the flow rates less than 0.02kg/ms. The grooved tube generally shows better heat transfer performances than the smooth tube. LiBr solution shows almost no absorption capability for the cooling water temperatures over $40^{\circ}C$. LiBr-$CaCl_2$ gives less decreasing rate in absorption capability at these temperatures and the heat transfer coefficient becomes less dependent on the types of tubes in use. Considering heat and mass transfer rates, LiBr-$CaCl_2$ solution is found to be more suitable than LiBr solution for air cooled absorber, which operates at higher temperature than water cooled absorber.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.531-536
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• 2011

Al doped $LiMn_2O_4$ ($LiMn_2O_4:Al$) synthesized by several Al doping process and Solid State method. The Al contents in $Mn_{1-x}Al_xO_2$ for $LiMn_2O_4:Al$ were analyzed 1.7 wt% by EDS. The $LiMn_2O_4:Al$ confirmed cubic spinel structure and approximately 5 ${\mu}m$ particles regardless of three kinds of doping process by solid state method. In the result of electrochemical performances, initial discharge capacity had 115 mAh/g in case of $LiMn_2O_4$ and 111 mAh/g of $LiMn_2O_4:Al$ after 100th cycle at room temperature. But the capacity retention results showed that $LiMn_2O_4$ and $LiMn_2O_4:Al$ were 44% and 69% respectively in the 100th cycle at 60$^{\circ}C$. Therefore we are confirmed that $LiMn_2O_4:Al$ increased the capacity retention about 25% than $LiMn_2O_4$, thus the effect of Al dopping on $LiMn_2O_4$ capacity retention.

• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.85-95
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• 2023

In recent years, solid-state Li metal batteries (SSLBs) have attracted significant attention as the next-generation batteries with high energy and power densities. However, uncontrolled dendrite growth and the resulting pulverization of Li during repeated plating/stripping processes must be addressed for practical applications. Herein, we report a plastic-crystal-based polymer/ceramic composite solid electrolyte (PCCE) to resolve these issues. To fabricate the one-side ceramic-incorporated PCCE (CI-PCCE) film, a mixed precursor solution comprising plastic-crystal-based polymer (succinonitrile, SN) with garnet-structured ceramic (Li₇La₃Zr₂O₁₂, LLZO) particles was infused into a thin cellulose membrane, which was used as a mechanical framework, and subsequently solidified by using UV-irradiation. The CI-PCCE exhibited good flexibility and a high room-temperature ionic conductivity of over 10^-3 S cm^-1. The Li symmetric cell assembled with CI-PCCE provided enhanced durability against Li dendrite penetration through the solid electrolyte (SE) layer than those with LLZO-free PCCEs and exhibited long-term cycling stability (over 200 h) for Li plating/stripping. The enhanced Li⁺ transference number and lower interfacial resistance of CI-PCCE indicate that the ceramic-polymer composite layer in contact with the Li anode enabled the uniform distribution of Li⁺ flux at the interface between the Li metal and CI-PCCE, thereby promoting uniform Li plating/stripping. Consequently, the Li//LiFePO₄ (LFP) full cell constructed with CI-PCCE demonstrated superior rate capability (~120 mAh g^-1 at 2 C) and stable cycle performance (80% after 100 cycles) than those with ceramic-free PCCE.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.541-551
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• 1988

The purpose of this investigation was to prepare multicomponent monolithic Li-Al-Si gels of composition(mol%) 16.67 Li2O-16.67 Al2O3-66.67 SiO2 and to convert the gels to monolithic glass-ceramic at low temperature without melting. The hydrolysis, DTA, TGA, TMA, SEM, pore distribution, density and the activation energy for crystallization of the glass-ceramic formation with rawmaterials of which tetraethl orhosilicate of networkforming cation(Si) is partially hydrolyzed, aluminum isoproxide and lithium methoxide prepared by Li-metal react with methanol were studied. The results were as follows : 1) Monolithic gels which were added with additional water, resulting in a total water content 2.5 to 3.0 times the stoichiometric amount required to fully hydrolyze the alkoxides. 2) Specimens were dried to form crylinders 60mm in length and 40mm in diameter in about 800 hrs at 5$0^{\circ}C$. 3) $\beta$-eucryptite crystals and $\beta$-spodumene crystals were detected in samples heated above 75$0^{\circ}C$. 4) Within the temperature and range of 25-50$0^{\circ}C$ and 1,00$0^{\circ}C$ the thermal expansion coefficient for crystallized samples were shown as 2.6-5.7$\times$10-7/$^{\circ}C$ and 7.4-12.5$\times$10-7/$^{\circ}C$, respectively. 5) The activation energy for the crystal growth was 11.01kcal/mol at 794$^{\circ}C$ to 85$0^{\circ}C$.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.17-23
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• 2023

In this study, the thermoluminescence kinetics of electron trap in Li₆Y_0.5Gd_0.5(BO₃)₃ (LY_0.5G_0.5BO) scintillator for neutron detection composed of Li, Gd, and B with a high neutron response cross-section were investigated. The thermoluminescence glow curve of the LY_0.5G_0.5BO scintillation single crystal was measured and analyzed using the peak shape method, the initial rise method, and the machine learning algorithm to evaluate the physical parameters of the electron trap. The glow curve of the LY_0.5G_0.5BO scintillation single crystal consisted of a single peak. As a result of analyzing this peak, the activation energy, emission order, and frequency factor of the electron trap were 0.61 eV, 1.1, and 1.7×10⁷ s^-1, respectively. In addition, the possibility of thermoluminescence analysis of scintillators using machine learning was confirmed.

• Journal of Korea Foundry Society
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• v.12 no.2
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• pp.149-154
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• 1992

The wetting behaviour of SiC/Al-Li composite interface has been investigated by using an infiltration method. The critical pressure for melt infiltration into SiC particulate preform has been determined by measuring the melt infiltration distance changes with the variation of applied pressure. The threshold pressure of pure Al, Al-0.2wt%Li, Al-0.5wt%Li for melt infiltration are 3.94, 3.93, $3.7Kg/cm^2$ respectively, which implies a slight improvement in wettability of SiC/Al composite by addition of Li. The threshold pressure for melt infiltration also changes with the variation of other parameters such SiC particulate size, SiC particulate fraction and melt temperature.

• Journal of the Korean Ceramic Society
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• v.33 no.10
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• pp.1079-1088
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• 1996

Discontinuous ${\gamma}$-LiAlO2 fibers for fiber-reinforcing MCFC matrixes have been produced by the sol-gel process using the centrifugal spinning apparatus of the Rotary type. Gel fibers could be obtained through spinning of stable LiAlO2 complex polymetric sols under the optimum spinning conditions (hollow-disc rotating velocity 9000 rpm sol feeding rate of 4ml/min flowing N2 temperature of 4$0^{\circ}C$ and flowing N2 pressure of 4 bar). It was found that defect free and densified ${\gamma}$-LiAlO2 fibers with the relative density of 98% and the mean diameter of 4.7${\mu}{\textrm}{m}$ were prepared when the spinned fibers were heat-treated to 100$0^{\circ}C$ on the specified heating schedule. in particular the mean diameter and length of fibers could be controlled by the pressure of flowing N2 and the chopping-sieving method respectively.