• Transactions on Electrical and Electronic Materials
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• 제12권2호
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• pp.68-71
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• 2011

[ $Ti_{1-x}W_xO_{2-y}$ ]solid solutions with compositions of x = 0.01(TW-1), x = 0.02(TW-2), x = 0.03(TW-3) and x = 0.04(TW-4) were prepared at 1,073 K in air under atmospheric pressure. All the solutions exhibited tetragonal symmetries. Nonstoichiometric chemical formulas have been obtained from oxidation-reduction titration and the partial substitution of $W^{6+}$ ions mainly caused the formation of $Ti^{3+}$ ion, rather than oxygen excess. Resistivities of the samples were highly dependent on humidity. The increase of the W amount resulted in an increase of $Ti^{3+}$ content, decrease of resistivity values and finally degradation of photocatalytic activities.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2011년도 임시총회 및 하계학술연구발표회
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• pp.17-18
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• 2011

• 한국구조물진단유지관리공학회 논문집
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• 제14권5호
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• pp.87-92
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• 2010

본 연구에서는 실리카흄 대체재로 활용 가능한 실리카 흄 무혼입 결합재(SFFB)의 치환율에 따른 고강도 콘크리트의 품질특성을 비교 분석하기 위하여, 실리카흄, SFFB의 2수준과 물-결합재비는 25, 35% 치환율은 실리카 흄 10%, SFFB 5, 10, 15(%)의 4수준으로 설정하였다. 실험을 실시한 결과, 목표 유동성을 확보하기 위한 고성능감수제의 첨가율은 물-결합재비가 낮을수록 증가하였으며, SFFB가 실리카 흄 보다 저흡수성을 갖는 재료적 특성으로 인해 고성능감수제의 첨가율이 감소하는 경향을 나타내었다. 압축강도에서는 SFFB 치환율이 10%일 경우 인장강도에서는 치환율이 15%일 경우 가장 우수한 강도를 나타내었으며, 자기수축에서는 W/B와 SFFB의 치환율과 상관없이 Plain(SF)에 비해 수축이 저감하는 것으로 나타났다.

• Journal of Magnetics
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• 제4권4호
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• pp.123-127
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• 1999

The Ga-stabilised $Sm_2Fe_{17-}$type alloy can hardly be disproportionated under ordinary HDDR condition. The HDDR characteristics of Ga-substituted $Sm_2Fe_{17-}$type alloy were examined, and, in particular, the effect of particle size on the disproportionation of the Ga-substituted alloy was investigated in detail. The reaction characteristics of the $Sm_2Fe_{17-}$type alloys with or without Ga-substitution with methane (CH4) gas are also examined. The Ga-stabilised $Sm_2Fe_{17-}$type alloy was able to be disproportionated significantly on heating up to 80$0^{\circ}C$ under hydrogen with normal pressure. The particle size influenced significantly on the disproportion-ation of the Ga-substitute alloy, and the materials with finer particle size (<40 ${\mu}{\textrm}{m}$) was fully disproportionated on heating up to around 80$0^{\circ}C$ under hydrogen gas with normal pressure. The Ga-substituted alloy has a very sluggish recombination kinetics with respect to the alloy without Ga-substitution. The $Sm_2Fe_{17}C_{x-}$type carbide was stabilised significantly by the Ga-substitution for Fe in the parent alloy. While the $Sm_2Fe_{17}C_x$ was disproportionated below 80$0^{\circ}C$ the Ga-stabilised $Sm_2Fe_{14}Ga_2C_x$ carbide remained intact even on heating up to 80$0^{\circ}C$.

• 한국전기전자재료학회논문지
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• 제14권1호
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• pp.20-25
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• 2001

To develop the piezoelectric actuator, the structural, dielectric and piezoelectric properties and electric fieldinduced strain of the ceramics(Pb$\_$1-2/Ba$\_$x/)[Mg$\_$1/2/W$\_$1/2/)$\_$0.03/-Ni$\_$1/3/Nb$\_$2/3/)$\_$0.12/-(Zr$\_$0.5/Ti$\_$0.5/)$\_$0.85/]O$_3$(x=0, 0.01, 0.03, 0.05, 0.07, 0.1) were investigated with the substitution of Ba. The tetragonality of crystal structure and grain size decreased by the substitution of Ba. Curie temperature decreased due to the decrease of the tetragonality, and dielectric constants increased with the substitution of Ba. The coercive field, remnant polarization and electromechanical coupling factor also decreased, whereas the piezoelectric constatns d$\_$33/ and d$\_$31/ were showed the highest value of 430 and 209(x10$\^$-12/C/N), respectively, because of the increase of dielectric constant. The strain induced by 60Hz AC electric field had the maximum value of 204x10$\^$-6/Δℓ/ℓ at the substitution of Ba 3mol%. As the applied electric field approaches to the coercive field, the piezoelectric element is depolarized and the electric field induced strain revealed non-linearity.

• Journal of Magnetics
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• 제7권4호
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• pp.143-146
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• 2002

Mechanical milling technique is considered to be a useful way of processing the fine Nd-Fe-B-type powder with high coercivity. In the present study, phase evolution of the $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ (x=0-0.6) alloys during the high energy mechanical milling and annealing was investigated. The effect of Co-substitution on the crystallization of the mechanically milled $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ amorphous material was examined. The Nd-Fe-B-type alloys can be amorphized completely by a high-energy mechanical milling. On annealing of the amorphous material, fine $\alpha$-Fe crystallites form first from the amorphous. These fine $\alpha$-Fe crystallites reacts with the remaining amorphous afterwards, leading to crystallization to $Nd_2Fe_{14}$B phase. The Co-substitution for Fe in $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ ($\mu$x=0∼0.6) alloys lower significantly the crystallization temperature of the amorphous phase to the $Nd_2Fe_{14}$B phase. The mechanically milled and annealed $Nd_{15}Fe_{77}B_8$ alloy without Co-substitution exhibits consistently better magnetic properties with respect to the alloys with Co-substitution.

• Asian-Australasian Journal of Animal Sciences
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• 제33권4호
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• pp.662-669
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• 2020

Objective: This study was conducted to evaluate the effect of red glasswort (RG) (Salicornia herbacea L.) curing on the physicochemical, textural and sensory properties of cooked pork loin ham (M. longissimus thoracis et lumborum). Methods: All treatments were cured with different salt and RG powder levels. RG0 treatment was prepared with only 4% NaCl (w/w) as a control, and RG25, 3% NaCl:1% RG (w/w); RG50, 2% NaCl:2% RG (w/w); RG75, 1% NaCl:3% RG (w/w); RG100, 0% NaCl:4% RG (w/w) treatments were prepared sequentially. All samples were individually vacuum packaged in polyethylene bags and stored for 7 d at 3℃±1℃. Results: The results showed that as the rate of RG substitution increased, pH value, redness, myofibrillar protein solubility, and myofibrillar fragmentation index increased (p<0.05), but salt concentration and shear force decreased (p<0.05). However, there were no significant differences in cooking loss and moisture content. In terms of sensory evaluation, RG100 exhibited higher scores in tenderness and juiciness than RG0 (p<0.05). Conclusion: The partial substitution of NaCl by RG could improve the physicochemical properties, textural and sensory characteristics of cooked pork loin. Therefore, it is suggested that RG as a natural salt replacer could be an effective ingredient for developing low-sodium cured hams.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1128-1134
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• 1997

Lactobacillus helveticus was inoculated to the fermentation liquid containing skin milk powder(SMT) plus soymilk, SMP plus isolated soybean protein(ISP), SMP plus ISP plus whey powder(WP) to increase the nutritional and economic value of commercial soy yogurt. The yogurt fermented with soymilk and SMP showed the lower acid production than of SMP and had significant beany flavor in the product. The yogurt prepared with ISP and SMP showed the higher cell number and lower acid production than that of SMP. Also, the partial substitution of SMP with ISP over 6%(w/w) produced less acceptable product due to gel production. The yogurt prepared by the partial substitution of SMP with ISP, WP and SMP showed the higher cell number and lower acid production than that of SMP and not bring about gel formation unlike the case of ISP. Sensory properties of yogurt substituted SMP with ISP and WP(38:62 mixture) below 4% were not significantly different from that of SMP and the sample containing the mixture over 6% and 0.067% artificial flavor showed lower sensory score due to beany taste than that of SMP. But increase of yogurt flavor up to 0.1% resulted in significantly high score in organoleptic acceptability. The separation of water occured in yogurt prepared by the combined mixture of ISP, WP and SMP, and this problem could be resolved by addition of Na-alginate and PGA at the concentration of 0.1%(w/w).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.54-59
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• 1998

This experimental Study presents the flow properties of mortar Using the Blast-furnace Slag Sand. It gives following result. The substitution rate is inversely proportional to flow. But W/C ratio is directly proportional to flow. Consequently Flow characteristics of the Blast-furnace mortar is simillar to the river sand mortar.

• 공업화학
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• 제3권3호
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• pp.407-411
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• 1992

본 연구는 상이동 촉매를 이용하여 group 6 금속 카르보닐 착물($M(CO)_6$ [M=Cr, Mo, W])의 CO 리간드를 두자리 전자쌍 주게 리간드(L)인 2, 2'-bipyridine와 2, 2'-biquinoline에 의해서 치환된 $M(CO)_4(L)_2$를 생성할 때 반응 시간, 촉매의 첨가량, 리간드의 종류가 생성물의 수율에 미치는 영향을 관찰하였다.