• 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.

• Analytical Science and Technology
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• v.10 no.6
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• pp.403-407
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• 1997

Separation factor for $^6Li$ and $^7Li$ have been determined using ion exchange resin having 1,7,13-trioxa-4,10,16-triazacyclooctadecane($N_3O_3$) as an anchor group. The lighter isotope, $^6Li$ is concentrated in the solution phase, while the heavior isotope, $^7Li$ is enriched in the resin phase. By Ccolumnl chromatography[0.9cm(I.D)${\times}$20cm(height)] using 2.0M ammonium chloride solution as an eluent, single separation factor, ${\alpha}$, 1.009. i.e.$(^7Li/^6Li)_{resin}$/$(^7Li/^6Li)_{solution}$ was obtained by the Glueckauf theory from the elution curve and isotope ratios.

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.2
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• pp.63-68
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• 2014

$^7Li$ nuclear magnetic resonance (NMR) spectra have been observed for $LiMPO_4$ (M = Fe, Mn) samples, as a promising cathode material of lithium ion battery. Observed $^7Li$ shifts of $LiFe_{1-x}Mn_xPO_4$ (x = 0, 0.6, 0.8, and 1) synthesized with solid-state reaction are compared with calculated $^7Li$ shift ranges based on the supertranferred hyperfine interaction of Li-O-M. Ex situ $^7Li$ NMR study of $LiFe_{0.4}Mn_{0.6}PO_4$ in different cut-off voltage for the first charge process is also performed to understand the relationship between $^7Li$ chemical shift and oxidation state of metals affected by delithiation process. The increment of oxidation state for metals makes to downfield shift of $^7Li$ by influencing the supertranferred hyperfine interaction.

• Korean Journal of Acupuncture
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• v.26 no.4
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• pp.23-38
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• 2009

Objectives : The purpose of this study was to identify the effect of the tonification & sedation manipulation for LI4 and KI7 on lacking of sweating in cold environment. Methods: The participants were divided into 3 groups as intact group without acupuncture, acupuncture group inserting and twisting with LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) and acupuncture group inserting and twisting with LI4 sedation and KI7 tonificaton method(LI4-purge KI7-tonify). We obtained baseline data at cold condition with the temperature $14{\pm}1^{\circ}C$. After making the participant staying in cold condition for 10 minute, we measured sweating rate in skin surface, body temperature, oxygen saturation, pulse rate, systolic blood pressure, diastolic blood pressure, deoxy-Hb and oxy-Hb in subcutaneous. Results : After acupuncture in cold environment, the sweating rate in skin surface significantly decreased in KI7-purge LI4-tonify group comparing the intact groups. The body temperature significantly increased in LI4-tonify KI7-purge and LI4-purge KI7-tonify groups comparing the intact group. The oxygen saturation significantly increased in LI4-tonify KI7-purge group comparing the intact group. Conclusions : These findings indicated that LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) could be effective for production of sweating in cold condition.

• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.735-741
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• 2004

$LiMn_{1.92}Co_{0.08}O_4$ and $LiNi_{0.7}Co_{0.3}O_2$ synthesized by a simplified combustion method had good electrochemical properties. Mixtures $LiMn_{1.92}Co_{0.08}O_4$-x wt$\%$ $LiNi_{0.7}Co_{0.3}O_2$ (x=9, 23, 33, 41, and 47) were prepared by milling for 30 min and their electrochemical properties were investigated. The electrode with x=9 had a relatively large first discharge capacity (109.9 mAh/g at 0.1 C) and good cycling performance. The decrease in the discharge capacity of the mixture electrodes with cycling is considered to result mainly from the degradation of $LiNi_{0.7}Co_{0.3}O_2$, caused by coating of $LiNi_{0.7}Co_{0.3}O_2$ with Mn dissolved from $LiMn_{1.92}Co_{0.08}O_4$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.601-605
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• 1999

$LiCoO_2$and $LiCo_{1-x}$$Ni_x$$O_2$ solid solutions were fabricated by the solid state reaction process. The structural cation mixing phenomena were investigated using XRD, SEM, particle size analysis and $^7$Li NMR,The synthesized LiCoO$_2$ and $LiCo_{1-x}Ni_XO_2$ microcrystallines showed the hexagonal layered structures. Mean particle sizes were increased with the increase of the amount of nickel in the solid solutions. The cation mixing effects were increased as increasing the fraction of nickel(x), x = 0.3, 0.5, 0.7. the peak frequency of $^7$Li NMR was shifted to the higher frequency and the line width increased as increasing the amount of nickel in the solid solutions.

• Korean Journal of Acupuncture
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• v.27 no.2
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• pp.203-216
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• 2010

Objectives : The purpose of this study is to identify the effect of tonifying or sedative manipulation on LI4 and KI7 for sweet deficiency under cold environment. Methods : The participants were divided into 4 groups; intact group without acupuncture(Intact), acupuncture group inserting straightly with LI4 & KI7 method((LI4-straight KI7-straight), acupuncture group inserting twisting with LI4 tonificaton & KI7 tonificaton method(LI4-tonify KI7-tonify) and acupuncture group inserting twisting with LI4 sedation & KI7 sedation method(LI4-purge KI7-purge). We obtained the baseline data under cold condition with the temperature $14{\pm}1^{\circ}C$. After making the participant staying under cold condition for 10 minute, we measured sweating rate on skin surface and biological responses such as body temperature, oxygen saturation, pulse rate, systolic blood pressure, diastolic blood pressure, deoxy-Hb and oxy-Hb in subcutaneous. Results : The sweating rate on skin surface was not different in all treatment groups compared to the intact group. The body temperature was significantly increased in LI4-straight KI7-straight group compared to the intact group. The oxygen saturation significantly increased in LI4-purge KI7-purge group compared to the intact group. The systolic blood pressure was significantly increased in LI4-purge KI7-purge group compared to the intact group. The deoxy-Hb was significantly decreased in LI4-purge KI7-purge group compared to the intact group. Conclusions : The above results, the effect of LI4, KI7 acupuncture due to the tonifying or sedative manipulation on sweating control could be observed. However, other biological responses with the acupuncture of tonifying or sedative manipulation were giving different expressions. We suggest that continued research of tonifying or sedative manipulation is of importance order to find these expressions.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.157-160
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• 2002

The dosage of intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons was evaluated with the calculation method validated with the phantom experiment. The production of both neutrons by near-threshold $^{7}$ Li(p,n)$^{7}$ Be and gamma rays by $^{7}$ Li(p,p'gamma)$^{7}$ Li in a Li target was calculated using Lee's method and their transport in the phantom was calculated with MCNP-4B. As a result, the region satisfying the requirements of the protocol in intra-operative BNCT for brain tumors in Japan was acknowledged to be comparable to present BNCT, for the proton energy of 1.900 MeV for example. A boron-dose enhancer (BDE) introduced in this study to increase $^{10}$ (n,$\alpha$)$^{7}$ Li dose in a living body was effective. The void used to increase doses in deep regions was also valid with the BDE. It was found that intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons is feasible.

• Analytical Science and Technology
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• v.11 no.4
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• pp.231-234
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• 1998

Separation factor for $^6Li$ and $^7Li$ has been determined using ion exchange resin having 1,7,13-trioxa-4,10,16-triazacyclooctadecane ($N_3O_3$) as an anchor group. The ion exchange capacity of the $N_3O_3$ ion exchanger was 2.0 meq/g dry resin. The lighter isotope, $^6Li$, is concentrated in the fluid phase, while the heavier isotope, $^7Li$, is enriched in the resin phase. By column chromatography [0.3 cm(I.D)${\times}$30 cm (height)] using 3.0 M ammonium chloride solution as an eluent, single separation factor, ${\alpha}$, 1.018, i.e. $(^7Li/^6Li)_{resin}/(^7Li/^6Li)_{fluid}$ was obtained by the Glueckauf theory from the elution curve and isotope ratios.

• Journal of radiological science and technology
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• v.28 no.1
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• pp.1-7
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• 2005

High-quality single crystals of pure $Li_2B_4O_7$ as well as $Li_2B_4O_7$ doped with Cu, Mn and Mg impurities (1.0mol%, respectively) have been grown from the melt of $Li_2CO_3+2B_2O_3$ by Czochralski method in platinum crucibles. To study the thermoluminescent properties, $Li_2B_4O_7$ series single crystal TLDs were made by cutting in the size of $4{\times}5{\times}1\;mm^3$. The glow curves show two or three peaks which can be easily deconvoluted. It is observed that room temperature($20{\sim}30^{\circ}C$) fadings of the dosimetric peaks of $Li_2B_4O_7$ series single crystal TLDs were about 10 % for 30 days. The relative photon energy response for $Li_2B_4O_7$ series single crystal TLDs were about 85 % when the responses were normalized to that measured with $^{60}Co\;(1.25\;MeV)\;{\gamma}-rays$. The measured data are in a good agreement with theoretical ones. The $Li_2B_4O_7$ series single crystal TLDs fabricated in this work can be used for monitoring personal and environmental radioactivity.