• Journal of the Korean Electrochemical Society
• /
• v.19 no.3
• /
• pp.80-86
• /
• 2016

High Ni content layered oxide materials for the positive electrode in lithium-ion batteries have high specific capacity. However, their poor electrochemical and thermal stability at elevated temperature restrict the practical use. A small amount of $Al_2O_3$ was added to the mixture of transition metal hydroxide and lithium hydroxide. The $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ was simultaneously doped and coated with $Al_2O_3$ during heat-treatment. Electrochemical characteristics of modified $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ were evaluated by the galvanostatic cycling and the LSTA(linear sweep thermmametry) at the constant voltage conditions. The nano-sized $Al_2O_3$ added materials show better cycle performance at elevated temperature than that of micro-sized $Al_2O_3$. As the added amount of nano-$Al_2O_3$ increased, the thermal stability of electrode also enhanced, but the use of 2.5 mol% Al showed the best high temperature performance.

• Journal of Bio-Environment Control
• /
• v.23 no.4
• /
• pp.337-341
• /
• 2014

Due to the nature of the ambient air temperature in summer in korea, the growth of crops in greenhouse normally requires cooling and dehumidification. Even though various cooling and dehumidification methods have been presented, there are many obstacles to figure out in practical application such as excessive energy use, cost, and performance. To overcome this problem, the lab scale experiments using lithium bromide(LiBr) solution and cooling coil for dehumidification and cooling in greenhouses were performed. In this study, preliminary experiment of dehumidification and cooling for the greenhouse was done using LiBr solution as the dehumidifying materials, and cooling coil separately and then combined system was tested as well. Hot and humid air was dehumidified from 85% to 70% by passing through a pad soaked with LiBr, and cooled from 308K to 299K through the cooling coil. computational Fluid Dynamics(CFD) analysis and analytical solution were done for the change of air temperature by heat transfer. Simulation results showed that the final air temperature was calculated 299.7K and 299.9K respectively with the deviation of 0.7K comparing the experimental value having good agreement. From this result, LiBr solution with cooling coil system could be applicable in the greenhouse.

• Economic and Environmental Geology
• /
• v.20 no.1
• /
• pp.35-60
• /
• 1987

The geochemical characteristics including minerals, major and trace elements chemistries of the Proterozoic, Jurassic and Cretaceous granites in Korea are systematically summarized and intended to decipher the origin and crystallization process in connection with the tectonic evolution. The granites in Korea are classified into three different ages of the granites with their own distinctive geochemical patterns: 1) Proterozoic granitoids; 2) Jurassic granites(cratonic and mobile belt); 3) Cretaceous-Tertiary granites. The Proterozoic granite gneisses (I-type and ilmenite-series) formed by metamorphism of the geochemically evolved granite protolith. The Proterozoic granites (S-type and ilmenite-series) produced by remobilization of sialic crust. The Jurassic granites (S-type and ilmenite-series) were mainly formed by partial melting of crustal materials, possibly metasedimentary rocks. The Cretaceous granites (I-type and magnetite-series) formed by fractional crystallization of parental magmas from the igneous protolith in the lower crust or upper mantle. The low temperature ($315{\sim}430^{\circ}C$) and small temperature variations (${\pm}20{\sim}30^{\circ}C$) in the cessation of exsolution of perthites for the Proterozoic and Jurassic granites might have been caused by slow cooling of the granites under regional metamorphic regime. The high ($520^{\circ}C$) and large temperature variations (${\pm}110^{\circ}C$) of perthites for the Cretaceous granites postulate that the rapid cooling of the granitic magma. In terms of the oxygen fugacity during the feldspar crystallization in the granite magmas, the Jurassic mobile belt granites were crystallized in the lowest oxygen fugacity condition among the Korean granites, whereas the Cretaceous granites in the Gyeongsang basin at the high oxygen fugacity condition. The Jurassic mobile belt granites are located at the Ogcheon Fold Belt, resulting by closing-collision situation such as compressional tectonic setting, and emplaced into a Kata-Mesozonal ductile crust. The Jurassic cratonic granites might be more evolved either during intrusion through thick crust or owing to lower degree of partial melting in comparison with the mobile belt granites. The Cretaceous granites are possibly comparable with a continental margin of Andinotype. Subduction of the Kula-Pacific ridge provided sufficient heat and water to trigger remelting at various subcrustal and lower crustal igneous protoliths.

• Journal of Sensor Science and Technology
• /
• v.12 no.6
• /
• pp.273-281
• /
• 2003

A stoichiometric mixture for $CdIn_2Te_4$ single crystal was prepared from horizontal electric furnace. The $CdIn_2Te_4$ single crystal was grown in the three-stage vertical electric furnace by using Bridgeman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. The (001) growth plane of oriented $CdIn_2Te_4$ single crystal was confirmed from back-reflection Laue patterns. The carrier density and mobility of $CdIn_2Te_4$ single crystal measured with Hall effect by van der Pauw method are $8.61{\times}10^{16}\;cm^{-3}$ and $242\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CdIn_2Te_4$ single crystal obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.4750\;eV-(7.69{\times}10^{-3}\;eV)T^2/(T+2147)$. After the as-grown $CdIn_2Te_4$ single crystal was annealed in Cd-, In-, and Te-atmospheres, the origin of point defects of $CdIn_2Te_4$ single crystal has been investigated by the photoluminescence(PL) at 10 K. The native defects of $V_{Te}$, $Cd_{int}$, and $V_{Cd}$, $Te_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Cd-atmosphere converted $CdIn_2Te_4$ single crystal to an optical n-type. Also, we confirmed that In in $CdIn_2Te_4$ did not form the native defects because In in $CdIn_2Te_4$ single crystal existed in the form of stable bonds.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.11 no.1
• /
• pp.51-56
• /
• 1982

The thermal degradation of 0.05M glucose-arginine model system was occurred during heat treatment for 0$\sim$7 hours at $60{\sim}120^{\circ}C$. and the melanoid in formation was investigated as a function of temperature. The decomposition reaction of glucose and arginine, as well as the reaction of melanoidin formation, followed first-order kinetics, except the reaction at $120^{\circ}C$. and the rate constants ($hr^{-1}\times 10^3$) of those reactions were ranged from 14.20 to 837. 10. Temperature dependence of the rate constants was characterized by the Arrhenius equation, except the reaction at $120^{\circ}C$. The ranges of activation energy and $Q_{10}$ values were 12.122$\sim$18.142 kcal/mole and 1.65$\sim$2.12, respectively.

• Journal of Animal Science and Technology
• /
• v.54 no.1
• /
• pp.15-22
• /
• 2012

This study was conducted to investigate the effects of grain sources on the ruminal methane production in Hanwoo steers. Six Hanwoo steers (BW = 614.4 ${\pm}$ 8.3 kg) were fed, on a DM basis (TDN 6.91 kg), 10% rice straw and 90% barley or corn based concentrate, respectively, according to Korean Feeding Standards (Hanwoo). Each period lasted 18 days including a 14-day adaptation and a 4-day measuring period. The steers were in the ventilated hood-type respiration chamber system (one cattle per chamber) during each measuring period to measure heat and methane production for 1 day. Nutrient intake and digestibility were not affected by steer fed grain sources. Methane concentration was not affected by steer fed either barley or corn-based concentrate, respectively (0.022% vs. 0.025%). Methane production was greater by steers fed corn than those fed barley (119.3 g/day vs. 139.4 g/day). This result indicated that methane emission factor by maintenance energy requirement for the late fattening Hanwoo fed corn was higher than the steers fed barley (43.6 kg/head/year) vs. corn (50.9 kg/head/year). Methane conversion rate (Ym) was 0.04 Ym and 0.05 Ym for barley and corn, respectively.

• Journal of Animal Environmental Science
• /
• v.18 no.1
• /
• pp.1-8
• /
• 2012

The study was conducted to investigate the effects of climate on indoor environment of a swine house with natural. This study was tested in the beef swine stall at Young-in, Kyung-ki do. The test was experimented for the effect of interior environment by the outdoor environment and the interior-pan. The results are as follows. 1. In test 1 ($T_{out}$ : $25.7^{\circ}C$, without fan), an indoor air flow pattern was showed that entered from sidewall winch-curtain to went out of a indoor by the ridge winch-curtain. And the velocity of a section of the center was measured two times as large as the velocity of the floor. It is the acceleration of the velocity by thermal buoyancy. And, the entered air was rapidly dissipated by flow energy. So that in the swain livestock with sidewall winch-curtain is effected by thermal buoyancy. And the air temperature of the indoor was distributed more higher as compared with the outdoor temperature. This result is caused by the sensible heat from swine and the ventilation is restricted. 2. In test 2 (($T_{out}$ : $25.7^{\circ}C$, with fan), the velocity of a section of the center was measured more higher as compared with the test 1. And the variance of air velocity was distributed higher as compared with the test 1. This result is showed dead region of air flow with a fan operation. And, the variance of gas density was distributed lower as compared with the test 1.

• Economic and Environmental Geology
• /
• v.24 no.2
• /
• pp.131-150
• /
• 1991

The Weolseong diatreme was temporally and spatially related to the intrusion of the Gadaeri granite, and was -mineralized by meteoric aqueous fluids. In the Nokdong As-Zn deposit, pyrite, aresenopyrite and sphalerite are the most abundant sulfide minerals. They are associated with minor amount of magnetite, pyrrhotite, chalcopyrite and cassiterite, and trace amounts of Pb-Sb-Bi-Ag sulphosalts. The AsZn ore probably occurred at about $350^{\circ}C$ according to fluid inclusion and compositional data estimated from the arsenic content of arsenopyrite and iron content of sphalerite intergrown with pyrrhotite + chalcopyrite + cubanite. Heating studies of fluid inclusions in quartz indicate a temperature range between 180 and $360^{\circ}C$, and freezing data indicate a salinity range from 0.8 to 4.1 eq.wt % NaCl. The coexisting assemblage pyrite + pyrrhotite + arsenopyrite suggests that $H_2S$ was the dominate reduced sulfur species, and defines fluid parameter thus: $10^{-34.5}$ < ${\alpha}_{S_2}$ < $10^{-33}$, $10^{-11}$ < $f_{S_2}$ < $10^{-8}$, -2.4 < ${\alpha}_{S_2}$ < -1.6 atm and pH= 5.2 (sericte stable) at $300^{\circ}C$. The sulfur isotope values ranged from 1.8 to 5.5% and indicate that the sulfur in the sulfides is of magmatic in origin. The carbon isotope values range from -7.8 to -11.6%, and the oxygen isotope values from the carbonates in mineralized wall rock range from 2 to 11.4%. The oxygen isotope compositions of water coexisting with calcite require an input of meteoric water. The geochemical data indicate that the ore-forming fluid probably was generated by a variety of mechanisms, including deep circulation of meteoric water driven by magmatic heat, with possible input of magniatic water and ore component.

• Journal of Food Hygiene and Safety
• /
• v.32 no.5
• /
• pp.434-442
• /
• 2017

The UV light in sunlight breaks down the chemical bonds in a polyolefin polymer through a process called photodegradation, ultimately causing cracking, chalking, colour changes, and loss of physical properties such as impact strength, tensile strength, elongation, and others. UV absorbers are used to prevent or terminate the oxidation of plastics by UV light. They are receptive to UV radiation and dissipate the energy harmlessly as heat. Benzotriazoles and benzophenones are used mainly in polyolefins such as polyethylene and polypropylene. In this study, we have developed a method for the analysis of 12 UV absorbers, which are Uvinul 3000, Cyasorb UV 24, Uvinul 3040, Tinuvin 312 and P, Seesorb 202, Chimassorb 81, Tinuvin 329, 234, 326, 328 and 327, migrated from the food packaging materials into four food simulants for aqueous, acidic, alcoholic and fatty foods. The UV absorbers in food simulants were determined by reversed-phase high performance liquid chromatograph-ultraviolet detector with 310 nm after solid-phase extraction with a hydrophilic-lipophilic balance (HLB) cartridge or dilution with isopropanol. The analytical method showed a good linearity of coefficient ($R^2{\geq}0.99$), limits of detection (0.049~0.370 mg/L), and limits of quantification (0.149~1.120 mg/L). The recoveries of UV absorbers spiked to four food simulants ranged from 70.05% to 110.13%. The developed method would be used as a reliable tool to determine concentrations of the migrated UV absorbers.

• The Journal of Korean Medicine
• /
• v.17 no.1 s.31
• /
• pp.374-406
• /
• 1996

This study has been carried out to investigate the types of differential diagnosis of amnesia. The results are as follows; 1. Amnesia has various types of differential diagnosis(辨證分型) ; deficiency of both the heart and spleen(心脾兩虛型), deficiency of the heart(心虛型), deficiency of the kidney(腎虛型), breakdown of the coordination between the heart and the kidney(心腎不交型), mental confusion due to phlegm(痰迷心竅型), accumulation of stagnant blood(蓄血型), internal injury by seven emotion (七情所傷型). 2. The type of deficiency of both the heart and spleen(心脾兩虛型) occurs when the heart and spleen is injured by overthinking(思慮過度), The symptoms are heart palpitation(心悸), continuous palpitation(??), insomnia(少寐), hypochondric discomfort(心煩), dream disturbed sleep(多夢), being easy to be scared(易驚), dizziness(眩暈), these are caused by blood deficiency of the heart(心血不足), poor appetite(飮食不振), loss of appetite(納?), short breath(氣短), sense of turgid abdormen(腹部膨滿感), loose stool(泥狀便), these are caused by deficiency of the spleen(脾虛), lassitude and weakness (身倦乏力), lassitude of the extremities (四肢無力), dim complexion (面色少華), pale lips(舌質淡), thready and feeble(脈細弱無力), these are caused by deficiency of both qi and the blood(氣血虛損). The remedy is nourishing the heart-blood(養心血) and regulating the spleen(理脾土). I can prescribe the recipes such as Guibitang(歸脾湯), Gagambosimtang(加減補心湯), Seongbitang(醒脾湯), Insin-guisadan(引神歸舍丹), Insamyangyoungtang(人蔘養榮湯), Sojungjihwan(小定志丸), Yungjigo(寧志膏), Palmijungjihwan(八味定志丸), etc., 3. The type of deficiency of the heart(心虛型) occurs when the heart-blood is injured by the mental tiredness(神勞) and so blood cannot nourish the heart. The symptoms are amnesia(健忘), short breath(氣短), heart palpitation(心悸), perspire spontaneously(自汗), facial pallidness(顔面蒼白), pale lips (舌質淡白), feeble pulse and lassitude(脈虛無力), intermittent pulse(結代脈). The remedy is nourishing the hart and blood and allaying restlessness(補心益血安神). I can prescribe the recipes such as Chenwangbosimdan(天王補心丹), Jeongji-hwan(定志丸), Gaesimhwan(開心丸), Youngjigo(寧志膏), Chilseonghwan(七聖丸), Baegseogyoungtang(白石英湯), Oseohwan(烏犀丸), Yangsinhwan(養神丸), Guisindan(歸神丹), Bogsinsan(茯神散), Jinsamyohyangsan(辰砂妙香散), Cheongeumboksinsan(千金茯神散), Samjotang(蔘棗湯), jangwonhwan(壯元丸), Sa gunjatang(四君子湯) minus rhizoma atractylodis macrocephalae(白朮) plus rhizoma acori graminei(石菖蒲), radix polygalae(遠志), cinnabaris(朱砂), etc. 4. The type of deficiency of the kidney(腎虛型) occurs when the kidney-qi and kidney-essence is deficient(腎氣腎精不足) and so it cannot nourish the brain. The symptoms arc amnesia(健忘), ache at the waist and lassitude in the lower extremities(腰산腿軟), dizziness and tinnitus(頭暈耳嗚), emmission and premature ejaculation(遺精早泄), burning sensation of the five centres(五心煩熱), flushed tongue(舌紅), rapid and small palse(脈細數). The remedy is nourishing the kidney and strengthen the essence(補腎益精). I can prescribe the recipes such as Gagamgobonhwan(加減固本丸), Jeongjihwan(定志丸), Gongseongchlmjungdan(孔聖枕中丹), Yugmigihwanghwan(六味地黃丸) plus ra-dix polygalae(遠志), fructus schizandrae(五味子), Yugmigihwanghwan(六味地黃丸) plus radix polygalae(遠志), fructus schizandrae(五味子), rhizoma acori graminei(石菖蒲), semen zizyphi spinosae(酸棗仁), Palmihwan(八味丸) plus fructus schizandrae(五味子), semen zizyphi spinosae(酸棗仁). etc., 5. The type of breakdown of the coordination between the heart and the kidney (心腎不交型) occurs when the heart-fire(心火) and kidney-fluid(腎水) are imbalanced. The symptoms are amnesia(健忘), hypochondric discomfort(心煩), insomnia(失眠), dizziness and tinnitus(頭最耳嗚), feverish sensation m the palms and soles(手足心熱), emmision(遺精), ache at the waist and lassitude in the lower extremities(腰?腿軟), flushed tongue(舌紅), rapid pulse(脈數). The remedy is coordinating each other(交通心腎). I can prescribe the recipes such as Gangsimdan(降心丹), Jujaghwan(朱雀丸), Singyotang(神交湯), Simsinyang- gyotang(心腎兩交湯), Yugmihwan(六味丸) plus fructus schizandrae(五味子), radix polygalae(遠志), Yugmihwan(六味丸) plus fructus schizandrae(五味子), radix polygalae(遠志), rhizoma acari graminei(石菖蒲), semen zizyphi spinosae(酸棗仁), etc., 6. The type of mental confusion due to phlegm(痰迷心竅型) occurs when the depressed vital energy(氣鬱) create phlegm retention(痰飮) and phlegm stagnancy(痰濁) put the heart and sprit(心神) out of order. The symptoms arc amnesia(健忘), dizziness(頭暈), chest distress(胸悶), nausea(惡心), dull(神思欠敏), dull and slow facial expression(表情遲鈍), tongue with yellow and greasy fur(舌苔黃?), sliperry pulse(脈滑). The remedy is removing heat from the heart to restore consciousness and dispersing phlegm(淸心化痰開竅) I can prescribe the recipes such as Gamibogryeongtang(加味茯?湯), Goa-rujisiltang(瓜蔞枳實湯), Jusaansinhwan(朱砂安神丸), Dodamtang(導痰湯) plus radix saussurea(木香), Yijintang(二陳湯) plus succus phyllostachyos(竹瀝), rhizoma zingiberis(生薑) Ondamtang(溫膽湯) plus rhizoma acori graminei(石菖蒲), rhizoma curcumae aromaticae(鬱金), etc., 7. The type of accumulation of stagnant blood(蓄血型) occurs when the blood is accumulated in the lower part of body. The symptoms are amnesia(健忘), chest distress(胸悶), icteric skin(身黃), rinsing the mouth but don't wanting eat(漱水不欲燕), madness(發狂), black stool(屎黑), pain in the lower abdomen(小腹硬痛). The remedy is dispersing phlegm and absorb clots (化痰化瘀), I can prescribe the recipes such as Jeodangtang(抵當湯), Daejeodanghwan(代抵當丸), Hyeolbuchugeotang (血府逐瘀湯) plus rhizoma acori graminei (石菖蒲), rhizoma curcumae aromaticae(鬱金), Jusaansinhwan(朱砂安神丸) plus rhizoma curcumae aromaticae(鬱金), radix polygalae(遠志), semen persicae(桃仁), cortex moutan radicis(收丹皮), etc., 8. The type of internal injury by seven emotion(七情所傷型) occurs when the anger injures the will stored in the kidney(腎志). The symptoms are amnesia(健忘), heart palpitation(心悸). hot temper(易怒), being easy to be scared(善驚), panic(易恐). The remedy is relieving the depressed liver and regulating the circulation of qi(疏肝解鬱). I can prescribe the recipes such as Tongultang(通鬱湯), Sihosogantang(柴胡疏肝湯) plus rhizoma acari graminei(石菖蒲), rhizoma curcumae aromaticae(鬱金), etc.