• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Applied Chemistry for Engineering
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• v.17 no.6
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• pp.575-579
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• 2006

Solid electrolyte interface is formed on a carbon electrode used as an anode in Li-ion battery, which can be of $Li^{+}$ intercalation/deintercalation during the first cycle. The passivation film formed by a solvent decomposition during the initial charge process affects cell performance and it was one of the main reason of an initial irreversible capacity. This paper describes the use, for the first time, of $Li_2CO_3$ as the additive for the formation of a passivation film on the carbon surface to suppress the initial irreversible reaction. Chronopotentiometry, cyclic voltammetry, and impedance spectroscopy were used to investigate the effects of the $Li_{2}CO_{3}$ additive. Scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction were also used to monitor changes in the surface morphology and composition of the passivation film formed by solvent decomposition and the precipitation of $Li_{2}CO_{3}$. The addition of $Li_{2}CO_{3}$ to a solution of 1 M $LiPF_{6}$/EC:MA (1:3, v/v) resulted in a decrease in the initial irreversible capacity and it was due to the suppression of the solvent decomposition on the electrode surface.

• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.718-724
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• 2018

In this study, the $Ni_{0.9}Co_{0.05}Ti_{0.05}(OH)_2$ precursor was prepared by the concentration gradient co-precipitation method. In order to overcome the structural change due to oxygen desorption in the cathode active material with high nickel content, the physical and electrochemical analysis of the cathode active material according to the calcination temperature were investigated. Physical properties of $Li_{1.05}Ni_{0.9}Co_{0.05}Ti_{0.05}O_2$ were analyzed by FE-SEM, XRD and TGA. The electrochemical performance of the coin cell using a cathode active material and $LiPF_6$(EC:EMC=1:2 vol%) electrolyte was evaluated by the initial charge/discharge efficiency, cycle retention, and rate capabilities. As a result, the initial capacity and initial efficiency of cathode materials were excellent with 244.5~247.9 mAh/g and 84.2~85.8% at the calcination temperature range of $750{\sim}760^{\circ}C$. Also, the capacity retention exhibited high stability of 97.8~99.1% after 50cycles.

• Journal of Animal Science and Technology
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• v.60 no.11
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• pp.26.1-26.9
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• 2018

Background: This experiment aimed at assessing polyphenol-rich plant biomass to use in complete feed making for the feeding of ruminants. Methods: An in vitro ruminal evaluation of complete blocks (CFB) with (Acacia nilotica, Ziziphus nummularia leaves) and without (Vigna sinensis hay) polyphenol rich plant leaves was conducted by applying Menke's in vitro gas production (IVGP) technique. A total of six substrates, viz. three forages and three CFBs were subjected to in vitro ruminal fermentation in glass syringes to assess gas and methane production, substrate degradability, and rumen fermentation metabolites. Results: Total polyphenol content (g/Kg) was 163 in A. nilotica compared to 52.5 in Z. nummularia with a contrasting difference in tannin fractions, higher hydrolysable tannins (HT) in the former (140.1 vs 2.8) and higher condensed (CT) tannins in the later (28.3 vs 7.9). The potential gas production was lower with a higher lag phase (L) in CT containing Z. nummularia and the component feed block. A. nilotica alone and as a constituent of CFB produced higher total gas but with lower methane while the partitioning factor (PF) was higher in Z. nummularia and its CFB. Substrate digestibility (both DM and OM) was lower (P < 0.001) in Z. nummularia compared to other forages and CFBs. The fermentation metabolites showed a different pattern for forages and their CFBs. The forages showed higher TCA precipitable N and lower acetate: propionate ratio in Z. nummularia while the related trend was found in CFB with V. sinensis. Total volatile fatty acid concentration was higher (P < 0.001) in A. nilotica leaves than V. sinensis hay and Z. nummularia leaves. It has implication on widening the forage resources and providing opportunity to use forage biomass rich in polyphenolic constituents in judicious proportion for reducing methane and enhancing green livestock production. Conclusion: Above all, higher substrate degradability, propionate production, lower methanogenesis in CFB with A. nilotica leaves may be considered useful. Nevertheless, CFB with Z. nummularia also proved its usefulness with higher TCA precipitable N and PF. It has implication on widening the forage resources and providing opportunity to use polyphenol-rich forage biomass for reducing methane and enhancing green livestock production.

• Journal of Welding and Joining
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• v.30 no.1
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• pp.64-71
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• 2012

The characteristics of high heat input (342kJ/cm) EG (Electro Gas Arc) welded joint of EH36-TM steel has been investigated. The weld metal microstructure consisted of fine acicular ferrite (AF), a little volume of polygonal ferrite (PF) and grain boundary ferrite (GBF). Charpy impact test results of the weld metal and heat affected zone (HAZ) met the requirement of classification rule (Min. 34J at $-20^{\circ}C$). In order to evaluate the relationship between the impact toughness property and the grain size of HAZ, the austenite grain size of HAZ was measured. The prior austenite grain size in Fusion line (F.L+0.1 mm) was about $350{\mu}m$. The grain size in F.L+1.5 mm was measured to be less than $30{\mu}m$ and this region was identified as being included in FGHAZ(Fine Grain HAZ). It is seen that as the austenite grain size decreases, the size of GBF, FSP (Ferrite Side Plate) become smaller and the impact toughness of HAZ increases. Therefore, the CGHAZ was considered to be area up to 1.3mm away from the fusion line. Results of TEM replica analysis for a welded joint implied that very small size ($0.8\sim1.2{\mu}m$) oxygen inclusions played a role of forming fine acicular ferrite in the weld metal. A large amount of (Ti, Mn, Al)xOy oxygen inclusions dispersed, and oxides density was measured to be 4,600-5,300 (ea/mm2). During the welding thermal cycle, the area near a fusion line was reheated to temperature exceeding $1400^{\circ}C$. However, the nitrides and carbides were not completely dissolved near the fusion line because of rapid heating and cooling rate. Instead, they might grow during the cooling process. TiC precipitates of about 50 ~ 100nm size dispersed near the fusion line.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.220-227
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• 2012

The objective of this study was to investigate the influence of emulsion processing with various homogenization treatments on the physical properties of nanoparticles. For the manufacturing of nanoparticles, by taking the emulsion-diffusion method, various coating materials, such as gum arabic, hydroxyethyl starch, polycarprolactone, paraffin wax, ${\kappa}$-carrageenan and emulsifiers like Tween$^{(R)}$60, Tween$^{(R)}$80, monoglyceride and Pluronic$^{(R)}$F68, were added into the emulsion system. Furthermore, the various speeds (7,000 rpm to 10,000 rpm), and times (15 s to 60 s) of homogenization were treated during the emulsion- diffusion process. NEO II homomixer was the most effective homogenizer for making nanoparticles as 51 nm ($D_{10}$) and 26 nm ($D_{50}$). To manufacture smaller nanoparticles, by using NEO II homomixer, 10,000 rpm of agitation speed, polycaprolactone as coating material, and Pluronic$^{(R)}$F68 as an emulsifier were the optimum operating conditions and components. For the stability of nanoparticles for 7 days, $20^{\circ}C$ of storage temperature was appropriate to maintain the particle size. From these results, the type of homogenizer, homogenization speed, homogenization time and storage temperature could affect the particle size. Moreover, type of coating materials and emulsifier also influenced the size and stability of the nanoparticles.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.302-311
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• 1995

Benfuresate or oxolinic acid, as an experimental pesticide, was applied to the different textural paddy or upland soil respectively under the field condition and the residual concentrations were determined. Six kinetic models were employed to characterize the best-fit kinetic model describing the residual pattern of benfuresate or oxolinic acid and the $t\frac{1}{2}$ estimated from each model was comparatively assessed. All of the six models explained significantly the residual patterns of the pesticides but the empirical models such as PF, EL, and PB were not recommendable for the $t\frac{1}{2}$ estimation. Among theoretical models, the residual patterns were followed in the orders of the second-order(SO)>first-order(FO)>zero-order(ZO) kinetics, judging from the size and significance of coefficient of determination and standard error. However, the multiple FO model, consisting of the fast and slow decomposition steps, was better than the single FO model for the residual pattern and the $r^2$ in this case became similar to that of SO kinetic model. Thus the multiple FO and SO models were represented as the best fit model of the experimental pesticide. The $t\frac{1}{2}$ of benfuresate estimated from the single FO kinetic model in Weolgog and Cheongwon series was 49 and 63 days, respectively, which were 20 and 13% longer than the respective $t\frac{1}{2}$ from the SO kinetic model. The $t\frac{1}{2}$ of oxolinic acid from the FO model in Yonggye and Ihyeon series were 87 and 51% longer than those from the SO kinetic model, respectively. These results demonstrated that the best-fit model representing the residual pattern of a pesticide and the resultant $t\frac{1}{2}$ might be variable with the kinds of pesticides and the environmental conditions. Therefore it is recommended that the half-life of a pesticide be assessed from the best-fit model rather than from the FO kinetic model uniformly.

• Journal of the Korean Electrochemical Society
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• v.2 no.3
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• pp.123-129
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• 1999

Initial electrochemical characteristics of $LiCoO_2$ electrode for lithium ion battery with various content of super s black as conductive material were evaluated through the charge/discharge with the potential range of 4.3V to 2.0V versus $Li^+/Li^+$. The rate of C/4 and C/2 by the 3 electrode test cell composed with an electrolytic solution of 1 mol/l $LiPF_6/EC+DEC(1:3\;by\; weight)$. Lithium was used as reference electrode. High impedance charge behavior was observed at early stage of charge. In the case of $3\%w/w$ of super s black as conductive material, the specific resistance of the high impedance releasing was $3.82\;{\Omega}\;{\cdot}\;g-LiCoCo_2$ at the current density of $0.5 mA/cm^2$, which corresponds 7 times of the specific resistance of electrode $(0.728 g-LiCoO_2)$. At second charge, the specific resistance of the high impedance releasing was 63 mn · g-Lico02, which corresponds 12eio of the specific resistance of electrode and only $1.7\%$ of that of the first charge. The first charge and discharge specific capacities at C/4 rate were 160-161 and $153\~155mAh/g-LiCoO_2$, respectively, to lead $95.4\~96.4\%$ of coulombic efficiencies and ca. $6 mAh/g-LiCoO_2$ of initial irreversible specific capacity. Specific resistance at the end of charge and rest showed low value at content of super s black between 2 and $7\%w/w$, which agreed with characteristics of irreversible specific capacity. Capacity densities were reduced by the increasing the content of conductive material. They were 447 and 431mAh/ml when 2 and $2.9\%w/w$ of super s black were used, respectively, at the rate of C/4.

• Journal of Life Science
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• v.19 no.8
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• pp.1093-1103
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• 2009

The purpose of this study was to analyze the effects of ballet program training at the Royal Academy of dance (RAD) on body composition (BC), physical fitness (PF) and bone mineral density (BMD) in college women. The subjects for this study were 14 females aged 19 to 22, who were divided into the Experimental group (n=7, EG) and the Control group (n=7, CG). The RAD ballet program training was done by 7 subjects (EG), 60 minutes per day, three times a week for 12 weeks. The TBF and %fat significantly decreased and LBM increased in the Experimental group, but all the variables of Body composition in the Control group did not significantly changed. The AMS, Sit ups, STF, SLJ CFB and 1,200 m R & W in the EG significantly increased, but 1,200 m R & W in the CG decreased. The lumbar vertebra (LV), femoral neck (FN), greater trochanter (GT) and ward's triangle (WT) did not significantly change in the EG, but LV, GT and WT in the CG decreased. There was no significant difference in osteopenia for EG, but there were increases in GT and WT for the CG. There was significant correlation between BMDs and body weight, TBF, LBM, %fat, BMI, AMS. There was significant correlation between LV and FN and LV and whole body. In conclusion, regular and continuous RAD training was effective in improving the body composition, physical fitness and bone mineral density. Consequently, RAD training will be effective for preventing osteopenia and osteoporosis, and for improving the health-related fitness for college and middle-aged women.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.954-964
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• 1996

Background : The type of the infiltrating cells in al veolitis may be determined by the chemokines in the lesion. MIP-1 ${\alpha}$, a C-C type chemokine, stimulates proliferation and cytokine secretion from macrophages and induces early neutrophilic and later monocytic inflammation in vi vo. IL-8, a C-X-C type chemokine is known to attract neutrophils and T-lymphocytes. This study is performed to find out the relative role of two different chemokines in diffuse interstitial lung disease. Subject and Method : We measured the secretion of MIP- 1 ${\alpha}$ and IL-8 from alveolar macrophages(AM), and their level in BAL fluid of 26 patients with DILD (10 IPF, 4 collagen disease, 10 sarcoidosis, and 2 hypersensitivity pneumonitis) and 7 normal control. Result: IL-8 secretion was significantly increased in patients with DILD ($8.15{\pm}4.58$ ng/ml) than in normal ($1.10{\pm}0.93$ ng/ml, p=0.0003). Significant correlation was found between IL-8 secretion and total cell number in BAL fluid (r=0.484, p=0.0068), %(r=0.592, p=0.0004) and No. (r=0.516, p=0.0042) of lymphocyte, and % of AM (r=-0.505, 0.0032). MIP- 1 ${\alpha}$ secretion was also increased in DILD ($2.41{\pm}1.45$ ng/ml) compared to control ($0.63{\pm}0.30$ ng/ml, p=0.0031), and showed a tendency of correlation with total cell number (r=0.368, p=0.0456) and No. of alveolar macrophages (r=0.356, p=0.0579) in BAL fluid. The concentration of IL-8 in BAL fluid was significantly increased in the patients with DILD ($40.4{\pm}34.5$ pg/ml) compared to control ($3.90{\pm}2.47$ pg/ml, p=0.0094) and it showed a significant correlation with the total cell number (r=0.484, p=0.0068), %(r=-0.505, p=0.0032) of AM, and % (r=0.592, p=0.0004) and No. (r=0.516, p=0.0042) of lymphocyte in BAL fluid. But there was a no significant difference in MIP- 1 ${\alpha}$ concentration in BAL fluid between normal control group and the patients with DILD. Conclusion : From the above results, we concluded that AM of DILD releases increased amount of both IL-8 and MIP- 1 ${\alpha}$ but IL-8 has better correlation with the type of alveolitis.