• 여성건강간호학회지
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• 제7권3호
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• pp.331-347
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• 2001

The purpose of this study was to compare the effects on labor pain and duration of delivery time for primipara women treated by Hob-Gog (LI-4) pressure. 1. The proposed hypothesis was that 'the score of labor pain could be lower in the group which had LI-4 pressure applied than in the control group'. 1-1. The sub hypothesis was that the score of subjective labor pain would be lower in the group which had LI-4 pressure applied than in the group which did not have LI-4 pressure applied. 1-2. Another sub hypothesis was that the score of objective labor pain would be lower in the group which had LI-4 pressure applied than in the group which did not have LI-4 pressure applied. 2. The proposed hypothesis was that 'the score of duration of delivery time could be shorter in the group which had LI-4 pressure applied than in the control group'. The design of this study was a nonequivalent control group non-synchronized post test only design to verify the effect on labor pain for primipara women treated by LI-4 pressure and to evaluate the benefits of using LI-4 pressure on some women and judging the degree of their labor pains in comparison with other primipara women not treated with LI-4 pressure. The subjects included 63 primipara women who underwent vaginal delivery, who were between 38-41 weeks intra uterine pregnancy; who did not have any complications; and who were under pitocin augmentation or induction. They were recruited with informed consent; 34 were in the control group and 29 were in the experimental group. The study was measured with a structured questionnaire consisting of general characteristics, knowledge related to delivery, subjective (Johnson, 1974) and objective(McLachlan, 1974) labor pain scale, data collection was done by research during the period from April, 2000 to July, 2000 and data was analyzed by descriptive statistics, $x^2$-test, and t-test. The results were as follows: 1. The scores of total labor pain in the group which had LI-4 pressure applied were lower($347.62{\pm}49.84$) than in the group($411.02{\pm}55.79$) which did not have LI-4 pressure applied; And these differences were statistically significant(t=4.7193, p=.000). 1-1. The scores of subjective labor pain in the group which had LI-4 pressure applied were lower($203.44${\pm}33.88$)$ than in the group ($$233.82{\pm}31.31$$) which did not have LI-4 pressure applied(t=3.6953, p=.000). 1-2. The scores of objective pain in the group which had LI-4 pressure applied were lower ($144.18{\pm}29.12$) than in the group which did not have LI-4 pressure applied($177.20{\pm}35.01$). but there were no statistically significant differences found in regard to the scores of objective pain(t=4.0271, p=.000). 3. The duration of delivery time in the group which had LI-4 pressure applied was shorter ($390.51min{\pm}111.91$) than in the group ($460.44min{\pm}190.78$)which did not have LI-4 pressure applied and the duration of delivery time in the experimental group was statistically more significant than that in the control group. therefore this thesis was adapted(t=1.734, p=.0879). It could be concluded that LI-4 pressure is effective in relation to labor pain and duration of delivery time for primipara women. Therefore it is necessary to increase the number of subjects to generalize this result.

• 한국결정성장학회지
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• 제18권6호
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• pp.248-252
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• 2008

전기전도성이 우수하면서 입자 크기가 작은 $LiFePO_4$ 분말을 얻기 위해서, 이종원소(Cr+B 또는 Cr+Al) 도핑이 $LiFePO_4$의 전기전도도에 미치는 영향과 열처리 조건이 입자 크기에 미치는 영향에 대해서 조사하였다. 조성이 $LiFe_{0.965}Cr_{0.03}B_{0.005}PO_4$ and $LiFe_{0.065}Cr_{0.03}Al_{0.005}PO_4$인 두 종류의 분말을 기계화학적 밀링법으로 혼합 후 $675{\sim}759^{\circ}C$에서 $5{\sim}10$시간 열처리하여 합성하였다. 이종원소 도핑은 입자성장을 촉진하였고 전기전도도를 높이는 효과가 있었다. $LiFe_{0.065}Cr_{0.03}Al_{0.005}PO_4$의 전기전도도는 $1{\times}10^{-8}S/cm$로 도핑하지 않은 것의 $5{\times}10^{-10}S/cm$보다 높았다.

• Korean Journal of Acupuncture
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• 제20권1호
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• pp.21-30
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• 2003

Objectives : The pain was induced on upper and lower incisor of the rat based on the theory of 'connections of upper incisor pain with stomach meridian and lower incisor pain with large intestine meridian'. Such acupoints as LI4 and ST36 were used for alleviation of upper and lower incisor pain. Methods : The digastric myogram (dEMG) was utilized for the pain measurement. Results : The ST36 acupuncture after induction of upper incisor pain was gradually decreased or increased the dEMG. The LI4 acupuncture after induction of upper incisor pain was gradually decreased the dEMG. The ST36+LI4 acupuncture after induction of upper incisor pain was gradually decreased the dEMG. We knew this thing which the ST36+LI4 acupuncture decreased the dEMG most greatly and kept long compared to ST36 acupuncture, LI4 acupuncture. Conclusions : Acupuncture treatment at the loci of not only ST36 acupuncture but LI4 acupuncture were relieved the upper incisor pain. It was well suitable to the theory 'connections of upper incisor pain with stomach meridian' that ST36 acupuncture decreased the upper incisor pain. But there was not to decrease the dEMG for the ST36 acupuncture. We are considered as tracing study continuously about ST36 acupuncture. It was not suitable to the theory 'connections of upper incisor pain with stomach meridian' that LI4 acupuncture decreased the upper incisor pain. These results was considered as the function by the characteristic of the LI4 acupoint.

• 한국전기전자재료학회논문지
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• 제15권4호
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• pp.361-366
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• 2002

Spinel $LiMn_{2-y}M_yO_4$ and $LiMn_{2-y}M_yO_4$ (M=Mg, Zn) powders were synthesized by solid-state method at $800^{\circ}C$ for 37h. Crystal structure and electrochemical properties were analyzed by X-ray diffraction, charge-discharge test, cyclic voltammetry and ac impedance to $LiMn_{2-y}M_yO_4$. All cathode material showed spinel structure in X-ray diffraction. Ununiform distortion which calculated by (111) face and (222) face was almost constant in spite of the change of the kind and the substituting ratio of the metal cation in $LiMn_{2-y}M_yO_4$ (M=Mg, Zn). $LiMn_{1.9}Mg_{0.05}Zn_{0.05}O_4/Li$ cell substituted $Mg^{+2}$ and $Zn^{+2}$ showed excellent discharge capacities than other cells, which it presented about 120mAh/g at the 1st cycle and about 73mAh/g at the 250th cycle, respectively. AC impedance of $LiMn_{2-y}M_yO_4/Li$ cells showed the similar resistance of about 65~110$\Omega$ before cycling.

• Journal of Electrochemical Science and Technology
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• 제3권2호
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• pp.63-67
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• 2012

We prepared various $LiNi_{0.8}Co_{0.15}Al_{0.05}O_2-LiFePO_4$ mixed-cathode electrodes by changing the content of $LiNi_{0.8}Co_{0.15}Al_{0.05}O_2$ and $LiFePO_4$ used, and we analyzed the electrochemical characteristics of the cathodes. We found that the reversible specific capacity of the cathodes increased and that the capacity retention ratios of the cathodes decreased during cycling as the content of $LiNi_{0.8}Co_{0.15}Al_{0.05}O_2$ increased. Conversely, we found that although the reversible specific capacity of the cathodes decreased because of the material composition, the cycle property of the cathodes increased when the $LiFePO_4$ content increased. We analyzed the thermal stability of the $LiNi_{0.8}Co_{0.15}Al_{0.05}O_2-LiFePO_4$ mixed-material cathodes by differential scanning calorimetry and found that it increased as the $LiFePO_4$ content increased.

• 센서학회지
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• 제27권1호
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• pp.36-39
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• 2018

Transparent olivine $LiNiPO_4$ thin films on sapphire substrates were fabricated by radio frequency (RF) magnetron sputtering. The X-ray diffraction patterns show these thin films have the phase of $LiNiPO_4$ with an ordered olivine structure indexed to the orthorhombic Pmna space group. $LiNiPO_4$ thin films deposited on sapphire substrates exhibit transmittance of about 83 %. It was confirmed that the $LiNiPO_4$ thin film exhibits a high potential of 5 V-class.

• 한국자기공명학회논문지
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• 제18권2호
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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.

• 한국세라믹학회지
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• 제42권7호
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• pp.503-508
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• 2005

A simple and effective method for the synthesis of LiMn$_{2}$O$_{4}$ powder as a cathode material for lithium secondary battery is reported. Micrometer size LiMn$_{2}$O$_{4}$ was prepared by combustion synthesis technique employing initial mixture of l.l LiNO$_{3}$ -1.3Mn-0.7MnO$_{2}$-1NaCl composition. Parametric study of the combustion process including molar ratio of Mn/MnO$_{2}$ and NaCl concentration were carried out under air atmosphere. The combustion products obtained were additionally heat treated at the temperature 900$^{\circ}C$ and the washed by distilled water. The results of charging-discharging characteristics revealed that LiMn$_{2}$O$_{4}$ cell synthesized in the presence of NaCl had a high capacity and much better reversibility than one formed without NaCl An approximate chemical mechanism for LiMn$_{2}$O$_{4}$ formation is proposed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.363-364
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• 2007

Phospho-olivine $LiFePO_4$ cathode materials were prepared by hydrothermal reaction at different temperatures. The structural performance of $LiFePO_4$ powders were characterized by X-ray diffraction (XRD). $LiFePO_4$/Li batteries were characterized electrochemically by charge/discharge experiments. The XRD results demonstrate that $LiFePO_4$ powder has an orthorhombic olivine-type structure with a space group of Pnmb. Among the synthesized cathode materials, $LiFePO_4$synthesized at $170^{\circ}C$ and subsequently annealed at $500^{\circ}C$ shows the best electrochemical properties. It shows initial discharge capacity of $167\;mAh\;g^{-1}$ (98% of the theoretical capacity) close to the theoretical capacity of $LiFePO_4$ ($170\;mAh\;g^{-1}$) at 0.1 C rate, which is ascribed to the enhanced degree of crystallinity, better phase purity, more spherical and more finely dispersed nanoparticles, crystallization and activation of small amount impurity.

• 한국세라믹학회지
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• 제41권10호
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• pp.735-741
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• 2004

단순화한 연소법에 의해 합성한 $LiMn_{1.92}Co_{0.08}O_4$와 $LiNi_{0.7}Co_{0.3}O_2$의 혼합물의 전기화학적 성질을 알아보기 위하여, 30분 동안 milling하여 $LiMn_{1.92}Co_{0.08}O_4$-x wt$\%$ $LiNi_{0.7}Co_{0.3}O_2$ (x=9, 23, 33, 41, and 47) 조성의 혼합물을 제조하였다. x=9 조성의 전극이 비교적 큰 초기방전용량(109.9mAh/g at 0.1C)과 좋은 싸이클 성능을 가지고 있었다. 싸이클링에 따른 혼합물 전극의 방전용량 감소는 주로 $LiNi_{0.7}Co_{0.3}O_2$의 퇴화에 기인한다고 생각된다. $LiNi_{0.7}Co_{0.3}O_2$의 퇴화는 $LiMn_{1.92}Co_{0.08}O_4$로부터 용해된 Mn이 $LiNi_{0.7}Co_{0.3}O_2$ 입자를 둘러싸서(coating) 일어나는 것으로 판단된다.