• Journal of the Korean Electrochemical Society
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• v.24 no.4
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• pp.120-132
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• 2021

Although the development of high-Nickel is being actively carried out to solve the capacity limitation and the high price of raw cobalt due to the limitation of high voltage use of the existing LiCoO₂, the deterioration of the battery characteristics due to the decrease in structural stability and increase of the Ni content. It is an important cause of delaying commercialization. Therefore, in order to increase the high stability of the Ni-rich ternary cathod material LiNi_0.6Co_0.2Mn_0.2O₂, precursor Ni_0.6Co_0.2Mn_0.2-x(OH)₂/xTiO₂ was prepared using a nanosized TiO₂ suspension type source for uniform Ti substitution in the precursor. It was mixed with Li₂CO₃, and after heating, the cathode active material LiNi_0.6Co_0.2Mn_0.2-xTi_xO₂ was synthesized, and the physical properties according to the Ti content were compared. Through FE-SEM and EDS mapping analysis, it was confirmed that a positive electrode active material having a uniform particle size was prepared through Ti-substituted spherical precursor and Particle Size Analyzer and internal density and strength were increased, XRD structure analysis and ICP-MS quantitative analysis confirmed that the capacity was effectively maintained even when the Ti-substituted positive electrode active material was manufactured and charging and discharging were continued at high temperature and high voltage.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1152-1159
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• 2013

Four male lambs (Katahdin; average live weight $25.9{\pm}2.9$ kg) with "T" type cannulas in the rumen and proximal duodenum were used in a $4{\times}4$ Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p<0.01), but decreased ruminal organic matter (OM) digestion (linear effect, p<0.01). Replacing corn with DDGS increased (linear, $p{\leq}0.02$) duodenal flow of lipids, NDF and feed N. But there were no treatment effects on flow to the small intestine of microbial nitrogen (MN) or microbial N efficiency. The estimated UIP value of DDGS was 44%. Postruminal digestion of OM, starch, lipids and nitrogen (N) were not affected by treatments. Total tract digestion of N increased (linear, p = 0.04) as the DDGS level increased, but DDGS substitution tended to decrease total tract digestion of OM (p = 0.06) and digestion of gross energy (p = 0.08). However, it did not affect the dietary digestible energy (DE, MJ/kg), reflecting the greater gross energy content of DDGS versus DR corn in the replacements. The comparative DE value of DDGS may be considered similar to the DE value of the DR corn it replaced up to 30% in the finishing diets fed to lambs.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.4
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• pp.161-171
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• 1997

$AB_2$ type Zr-based Laves phase alloys have been studied for potential application as negative electrode in Ni/MH batteries. However, They have a serious disadvantage of poor activation behavior in KOH solution. In this work, a new method of alloy design method was tried for improving Zr-based alloy activation. this method has focused on phase controlling to make multi-phase microstructure. In the case of multi-phase Zr-V-Mn-Ni shows good performance in activation, but activation mechanism has not been known. So, we were in search of elucidating this mechanism, Using morphological and electrochemical analysis, we could find that surface morphology and electocatalytic activity of the alloy change during immersion in KOH solution. V-rich second phases are selectively corroded and dissolved and then become Ni-rich phases. Resulting from these surface reaction in KOH solution, self-hydrogen charging occurs through Ni-rich phase. However, the alloy has poor cyclic durability because of such a corrosion mechanism. Therefore, finally we developed durable alloys by substitution of other alloying element.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.379-382
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• 2005

The new cationic meso-substituted N-quarternized 4-pyridylporphyrins and their metal derivatives were synthesized as novel chemotherapeutics. The level of DNA damage induced by porphyrins TOBut4PyP, TOBut4PyP, TOEt4PyPMn and TOBut4PyPMn and its dependence on the chemical structure of compounds were analyzed by the Comet-assay. On the base of data obtained, the investigated porphyrins may be arranged by their genotoxic activity in the following order: TOEt4PyP>TOEt4PyPMn>TOBut4PyP>TOBut4PyPMn. Thus, i) the genotoxicity of the Mn-derivatives of TOEt4PyP and TOBut4PyP is higher than the original porphyrins and ii) the genotoxicity of TOEt4PyP and TOEt4PyPMn is increased after substitution of a butyl radical for ethyl one. The applied Comet-assay permits to reveal the dependence of DNA damage induction on the chemical structure of porphyrins.

• The Korean Journal of Physiology
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• v.25 no.2
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• pp.159-170
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• 1991

In the rabbit renal artery, mechanisms of contraction by sodium depletion were investigated. The helical strips of isolated renal artery were immersed in the Tris-buffered salt solution. The contractions were recorded isometrically using a strain-gauge transducer. Na-free solution (Na was substituted by Li, choline or sucrose) produced contractions which were dependent on the nature of the Na substitutes. Na-free solution (choline) produced the contraction in ouabain-pretreated artery (Na loaded artery) even in the presence of verapamil. The amplitude of the contraction was dependent on the duration of the pretreatment with ouabain $(10\;^5M)$. Monensin potentiated the effect of ouabain on the contraction. Removal of Ca from bathing solution abolished the contraction and the substitution of Sr for Ca produced the contraction. Divalent cations such as Mg, Mn blocked the depolarization-induced contraction, while they had little effect on the Na-free contraction in Na loaded artery. These results suggest that the contraction induced by Na removal is dependent on the cellular Na content and may be caused by Ca influx via the Na-Ca exchange carrier.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.192-198
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• 2007

Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a major constituent of rhubarb. Although it has been claimed to have a wild spectrum of therapeutic value, its side effects, especially in human kidney cells have not been well characterized. In this study, we have carried out in vitro genetic toxicity test of emodin and microarray analysis of differentially expressed genes in response to emodin. The result of Ames test showed mutations with emodin treatment in base substitution strain TA1535 both with and without exogenous metabolic activation. Likewise, emodin showed mutations in frame shift TA98 both with and without exogenous metabolic activation. The result of COMET assay in L5178Y cells with emodin treatment showed DNA damage both with and without exogenous metabolic activation. Emodin did not increase micronuclei in CHO cells both with and without exogenous metabolic activation. 150 Genes were selected as differentially expressed genes in response to emodin by microarray analysis and these genes would be candidate biomarkers of genetic toxic action of emodin.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.199-204
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• 2007

Carbamates have excellent insecticidal activities against a broad spectrum of insects. They possess knocking-down, fast-killing, and systemic effects, however, they are toxic to mammals. In this study, we have carried out in vitro genetic toxicity test of methylcarbamate and microarray analysis of differentially expressed genes in response to methylcarbamate. Methylcarbamate did not show mutations in base substitution strain TA1535 both with and without exogenous metabolic activation. Methylcarbamate did not show mutations in frame shift TA98 both with and without exogenous metabolic activation. Methylcarbamate showed DNA damage based on single cell gel/comet assay in L5178Y cells both with and without exogenous metabolic activation. Methylcarbamate did not increase micronuclei in CHO cells both with and without exogenous metabolic activation. Microarray analysis of gene expression profiles in L5178Y cells in response to methylcarbamate selected differentially expressed 132 genes that could be candidate biomarkers of genetic toxic action of methylcarbamate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.59-61
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• 2005

In this paper, in order to develop the low temperature sintering ceramics for multilayer piezoelectric transformer, $Pb[(Mn_{1/3},Nb_{2/3})_{0.07}(Zn_{1/3}Nb_{2/3})_a(Zr_{0.48}Ti_{0.52})_{1-0.07-a}O_3]$ ceramics were manufactured with the variations of PZN from 2 to 14mol% and their dielectric and piezoelectric properties were investigated. Sintering temperature was varied from 910 to $1000^{\circ}C$. At 8mol% PZN substituted specimen sintered at $970^{\circ}C$, electromechanical coupling factor(kp), mechanical quality factor(Qm), dielectric constant and peizoelectric constant($d_{33}$) showed the optimal values of 0.536, 1803, 1551 and 328[pC/N), respectively, for multilayer piezoelectric transformer application.

• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.246-252
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• 2006

1,2-Dibromoethane(DBE) has been widely used as a soil fumigant, an additive to leaded gasoline and an industrial solvent. In this study, we have carried out in vitro genetic toxicity test of 1,2-dibromoethane and microarray analysis of differentially expressed genes in response to 1,2-dibromoethane. 1,2-Dibromoethane showed mutations in base substitution strain TA1535 both with and without exogenous metabolic activation. 1,2-Dibromoethane showed mutations in frame shift TA98 both with and without exogenous metabolic activation. 1,2-Dibromoethane showed DNA damage based on single cell gel/comet assay in L5178Y cells both with and without exogenous metabolic activation. 1,2-Dibromoethane increased micronuclei in CRO cells both with and without exogenous metabolic activation. Microarray analysis of gene expression profiles in L5178Y cells in response to 1,2-dibromoethane selected differentially expressed 241 genes that would be candidate biomarkers of genetic toxic action of 1,2-dibromoethane.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.683-686
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• 1995

Using by the x-ray diffractometry(XRD), the thermomagnetic analysis(TMA), a scanning electron microscopy (SEM-EDX), we knew that the $(Sm_{0.5}RE_{0.5})Fe_{11}Ti$ (RE=Ce,Pr,Nd,Sm,Gd,Tb) compounds were formed to tetragonal $ThMn_{12}$-type structure having a uniaxial magnetocrystalline anisotropy with easy magnetization c-axis. The intrinsic magnetic properties of those were determined by fitting the two magnetization curves of experimental and calculation magnetization. The anisotropy constant $K_{1}$ of this compounds was in the range of $1.75\;-\;9.2\;MJ/m^{3}$ and approximately one order higher than $K_{2}$. $SmFe_{11}Ti$ had the highest anisotropy of $K_{1}\;=\;9.2\;MJ/m^{3}$, $K_{2}\;=\;0.4\;MJ/m^{3}$ and ${\mu}_{o}H_{A}=\;19.8\;T$ among the compounds, substitution of any other rare earth elements for Sm decreased magnetocrystalline anisotropy.