• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.783-786
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• 2009

Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and ion chromatography(IC) were employed to analyze the thermal behavior of $Li_xCoO_2$ cathode material of lithium ion battery. The mass loss peaks appearing between 60 and 125 ${^{\circ}C}$ in TGA and the exothermic peaks with 4.9 and 7.0 J/g in DSC around 75 and 85 ${^{\circ}C}$ for the $Li_xCoO_2$ cathodes of 4.20 and 4.35 V cells are explained based on disruption of solid electrolyte interphase (SEI) film. Low temperature induced HF formation through weak interaction between organic electrolyte and LiF is supposed to cause carbonate film disruption reaction, $Li_2CO_3\;+\;2HF{\rightarrow}\;2LiF\;+\;CO_2\;+\;H_2O$. The different spectral DSC/TGA pattern for the cathode of 4.5 V cell has also been explained. Presence of ionic carbonate in the cathode has been identified by ion chromatography and LiF reported by early researchers has been used for explaining the film SEI disruption process. The absence of mass loss peak for the cathode washed with dimethyl carbonate (DMC) implies ionic nature of the film. The thermal behavior above 150 ${^{\circ}C}$ has also been analyzed and presented.

• The Journal of Korean Medicine
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• v.41 no.4
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• pp.120-132
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• 2020

Objectives: Hyperemesis gravidarum (HG) is defined as severe nausea and vomiting during pregnancy (NVP) with weight loss, ketonuria, and electrolyte imbalance. Many NVP or HG patients get hard to take herbal medicine since the smell and taste of it. Therefore, the distilled herbal medicines are often used in clinical practice. A 32-year-old, 14-week pregnant female was admitted for 3 weeks at a Korean medicine hospital. She was experiencing HG accompanied by 19.61% (10 kg) weight loss, ketonuria, and electrolyte imbalance. The patient received Bosaeng-tang gagambang in its distilled form, acupuncture, electro-acupuncture, sticker needles, cupping, moxibustion, and hydration during admission. The severity and frequency of NVP, weight loss, and ketonuria significantly improved without any side effects. Before the therapy, she admitted to two obstetrics and gynecology hospitals, 1 week each, with no improvement. This case presents the therapeutic potential of Korean medicine including herbal medicine in its diluted form for HG and NVP.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.181-187
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• 2022

As the charges/discharges of VRFB-ESS were repeated during 150cycles or more, the capacity of electrolyte in VRFB-ESS was decreased little by little. It results from the decreasing of the level of anolyte and the increasing of the valance value of the catholyte. Then, we tried to recover the capacity loss with 3 different ways. The first way was that the levels of anolyte and catholyte were allowed to be evenly equalized when the difference in the levels of two different electrolytes were severe. The second one was to lessen the valance value of the catholyte through the reduction reaction to 4-valant ions of 5-valant ions in the catholyte with the reductant, oxalic acid. The last one was that the all electrolytes of analyte and catholyte were allowed to be electro-chemically reduced to 3.5 of the valance value by oxidizing new electrolyte with 3.5 valance ions. The last way was the most effective to recover the capacity loss.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.471-473
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• 2006

An object of the present study is to provide a hollow fiber membrane humidifier capable of improving the humidification efficiency while lowering the pressure loss, and is suitably usable for PEMFC(Polymer Electrolyte Membrane Fuel Cell). The performance of PEMFC is decisively dependent on the humidity of the electrolyte membrane(fluorinated membrane) and a humidifier plays an important role in moisturizing electrolyte membrane. Especially this humidifier is adaptable for lower price to promote the commercialization of fuel cell vehicles and is passive type to be power free and to be volumetrically optimized. In this research, we propose the substitutes for the expensive fluorinated materials and the optimum dry-jet wet spinning conditions of hollow fiber membrane to get the fuel cell humidifier. In addition to that we established the standard method of evaluating the moisturizing performance of the humidifier of various materials.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.177-179
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• 2007

An object of the present study is to provide a hollow fiber membrane humidifier capable of improving the humidification efficiency while lowering the pressure loss, and is suitably usable for PEMFC(Polymer Electrolyte Membrane Fuel Cell). The performance of PEMFC is decisively dependent on the humidity of the electrolyte membrane(fluorinated membrane) and a humidifier plays an important role in moisturizing electrolyte membrane. Especially, this humidifier is a passive type(power-free) item and is volumetrically optimized. In this research, we propose the substitutes for the expensive fluorinated humidifier materials and the optimum dry-jet wet spinning conditions of hollow fiber membrane. In addition to that, This study will present an performance of an humidifier and compare computational results with the experimental data.

• International Journal of Safety
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• v.10 no.1
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• pp.1-4
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• 2011

The fuel cell is one of the green energy receiving a lot of attention. Among the fuel cells, it is generally referred to SOFC(solid oxide fuel cell) which is made up composites of a solid. SOFC has excellent merits in the side of environment and energy. However because of the high operating temperature, it has economic loss by the using of expensive materials and problems of structural instability by thermal stresses. Therefore, this study aims to the effect of analysis by the FEMLAB. The results have deformations and the maximum stresses from the variation of the thickness of vulnerability spots. The deformation shows expansion as 0.82% and the stress ${\sigma}_{xx}$ is 392MPa in electrolyte and -56.31MPa in anode. When increasing or decreasing the thickness to 50% of the reference thickness about the electrolyte which is vulnerable spots.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.1
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• pp.17-31
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• 2000

In order to investigate the effects of emitted-qi therapy(EQT) and cold water therapy(CWT) on the inhibition of the blood loss, the protein loss and the electrolyte loss in burned rats. The white blood cell, hematocrit and hemoglobin values in blood, and the total protein, albumin, globulin, $Na^+,\;Cl^-,\;K^+\;and\;Ca^{2+}$ values in serum were measured. The results were obtained as follows; 1. White blood cell count in blood was significantly increased in CWT group compared with control group. 2. Hematocrit value in bolld was significantly increase in EQT and CWT group compared with control group. 3. Hemoglobin value in blood was significantly increased in CWT group compared with control group. 4. Total protein value in serum was significantly increased in CWT group compared with control group. 5. Albumin value in serum was significantly increased in EQT and CWT group compared with control group. 6. Globulin value in serum tended to be increase in EQT and CWT group compared with control group, but it was not significant. 7. A/G ratio in serum was significantly increased in EQT and CWT group compared with contort group. 8. $Na^+$, value in serum was significantly increased in EQT and CWT group compared with ontrol group. 9. $K^+$, value in serum tended to be increased in EQT group compared with control group, but it was not significant. 10. $Cl^-$ value in serum was significantly increased in EQT and CWT group compared with control group. 11. $Ca^{2+}$ value in serum tended to be increased in EQT and CWT compared with control group, but it was not significant. According to the above results, the EQT and CWT inhibited the blood loss, the protein loss and the electrolyte loss. Therefore, it is considered that the EQT and CWT can be applied to the burn therapy.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.59-71
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• 2014

This study was conducted to find out the freezing hardness of apple tree as influenced by dwarfrootstocks, cultivars, and low temperature treatments. The dwarf-rootstocks used were M.9 and M.26, and three cultivars used were early-maturing 'Tsugaru', mid-maturing 'Hongro', and late-maturing 'Fuji'. Chilling temperatures were applied from $0^{\circ}C$ to $-40^{\circ}C$. Checking points of apple tree for freezing hardness were rootstock, trunk, feather, floral bud and foliar bud. Investigations were evaluated by the measure of water loss, electrolyte leaching, and sprouting. The results did not show the differences in water loss, electrolyte leaching, and sprouting by dwarf-rootstocks. Water loss of 'Fuji' was lower than that of 'Tsugaru' and 'Hongro', but sprouting ratio of 'Fuji' was higher than that of 'Tsugaru' and 'Hongro'. Water loss and electrolyte leaching increased as treated by lower temperature, while sprouting ratio decreased. In $-35^{\circ}C$ treatment, sprouting of rootstock and trunk part were higher than that of feather, while sprouting of floral bud was lower than that of foliar bud. Sprouting of bourse shoot at the accumulated low temperature in terms of $-10^{\circ}C$ per day was 100% in the 28 days, and sharply decreased about 50% in the 35 days. In conclusion, there were no differences in freezing hardness between M.9 and M.26, but freezing hardness of late-maturing cultivar was tended to stronger than that of early-maturing and mid-maturing cultivars. Freezing hardness of floral bud was extremely weak $-30^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.48 no.1
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• pp.110-115
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• 2011

$Gd_2O_3$-doped $CeO_2$ (GDC) and $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_3$ (LSCF) composite cathode materials were prepared in order to be applied to intermediate-temperature solid oxide fuel cells. The electrochemical polarization was evaluated using ac impedance spectroscopy involving geometric restriction at the interface between an ionic electrolyte and a mixed-conducting cathode. In order to optimize the cathode composites applicable to a GDC electrolyte, the cathode composites were evaluated in terms of polarization losses with regard to a given electrolyte, i.e., GDC electrolyte. The polarization increased significantly with decreasing temperature and was critically dependent on the compositions of the composite cathodes. The optimized cathode composite was found to consist of GDC 50 wt% and LSCF 50 wt%; the corresponding normalized polarization loss was calculated to be 0.64 at $650^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.25 no.2
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• pp.95-100
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• 1995

Serum electrolyte concentration and body weight were determined before and after exercise for 2h in Korean cyclists. The serum concentration of electrolytes (Na, Ca, Zn, K, P and Cl) was increased but that of Mg was decreased as a result of exercise. The increase of serum K and P concentration was statistically significant after exercise. As the exercise time increased, the loss of body weight also increased due to dehydration and sweat. The loss of body weight ranged 1.0 to 2.3 Kg as a function of exercise time but cyclists showed the exhaustion and muscle fatigue 2h after exercise. As the ambient temperature increased, the loss of body weight was slightly increased. However, frequent drinking water was required because of dehydration and thirst. Although frequent drinking water may reduce weight loss and thirst during exercise, sports drinking beverages simultaneously containing electrolytes and nutrients are more useful to replenish loss of water and electrolytes in an exhausted condition, resulting in the improvement of physical performance.