• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.55-59
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• 2010

The effect of aging on the precipitation of the $\sigma$ phase and corrosion resistance in W-substituted, super-duplex stainless steel was investigated. The volume fraction of the $\sigma$ phase and the current density increased as the aging temperature increased up to $750^{\circ}C$, and, then, they decreased. As aging time increased, the volume fraction of the $\sigma$ phase and the current density also increased. The $\sigma$ phase considerably influenced to corrosion resistance. When Mo was substituted for W in super-duplex stainless steel, the volume fraction of the $\sigma$ phase and the current density both decreased markedly.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.387-392
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• 1995

Though a variety of non-conventional feedstuffs have been successfully evaluated in research stations in Asian countries, there had been little adoption of these technologies at the small farm level. The methodology and results of three separate on-farm trials evaluation the possible use of some non-conventional feedstuffs in broiler diets under small farm conditions in Sri Lanka are reported in this paper. In all trials, the commercial mash, that in normally used in the farms, served as the control. In trials 1 and 2, 5 and 10% cassava leaf meal, respectively, was substituted (w/w) for the commercial mash and fed to broilers for six weeks. In trial 3, several non-conventional feedstuffs (cassava leaf meal, rubber seed meal, ipil ipil leaf meal and died poultry manure) were substituted (w/w) for the commercial mash at levels of 15-20%. The results demonstrated that these non-conventional feed resources can be used in broiler diets under small farm conditions, with no adverse effects on performance. The salient features of on-farm animal research are highlighted.

• Magazine of the Korea Concrete Institute
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• v.9 no.3
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• pp.149-156
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• 1997

In order to improve compressive strength of cement mortar, powder admixture(FAS) was mmufactured by mixing fly ash. Il-anhydite and silica hume, and superplasticizer was used for the control of fluidity reduction with the use of this admixture. Cement was substituted by 10, 20wt% of FAS respectively. At W/S = 0.40, the fluidity of' cement paste substituted by PAS was decreased. NSF and NT-2 were very effective fbr the control of fluidity reduction. As the particle size of U -anhydrite was fine, the fluidity of cement mortar was increased. The fluidity reduction of cement mortar substituted by 10wt% of FAS was controlled. The compressive strength of cement mortar substituted by 10wt% of FAS showed higher. value than that of 20wt%, expecially specimen(C1) substituted by 10wt% of $\gamma$ had the highest compressive strength value.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.55-59
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• 2012

Treatments of organic isothiocyanates (R-NCS) with $NaN_3$ in the presence of pyridine in water at room temperature gave corresponding various organic tetrazole-thiones, [$S=CN_4(R)$] (R = alkyl or aryl). Isolated products are obtained as white or yellow solids in good yields (76-97%). The molecular structure by X-ray diffraction study for one of products shows the proposed formation. In addition, one-pot synthesis of 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles has been demonstrated. Addition of alkyl or aryl halides into the mixture of organic isothiocyanates, $NaN_3$, and pyridine in water at room temperature exclusively formed 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles (S-derivatives) in high yields.

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.100-100
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• 2001

• Journal of Magnetics
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• v.4 no.4
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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$0^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1463-1482
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• 2002

Partially doped Aurivillius phases SrBi2N$b_{2-x}M_xO_9$ (M=Cr and Mo) were successfully synthesized and characterized. The extent of the substitution was limited at ~20 mole % because of the size differences between $Nb^{5+}$ and $Cr^{6+}$, and between $Nb^{5+}$ and $Mo^{6+}$. When the amount of substitution exceeded ~20 mole%, the phases began to collapse and the second phases were made. The dielectric constants of substituted compounds were enlarged nevertheless Cr or Mo is substituted. The increment is bigger in the Mo substituted compound than in the Cr doped one although the Nb(Cr)$O_6$ octahedra could be more strongly distorted than the Nb(Mo)$O_6$ octahedra since the ionic size difference between $Nb^{5+}$ and of $Cr^{6+}$ is much bigger than that between $Nb^{5+}$ and $Mo^{6+}$. Consequently, the dielectric constant of the substituted Aurivillius phase $Bi_2$A_{n-1}B_{n-x}M_xO_{3n+1}$$ depends on the extent of distortion of the B$O_6$ octahedra and more strongly on the polarizability of the metal.

• Korean Journal of Poultry Science
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• v.11 no.2
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• pp.115-125
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• 1984

The Waste Rice Straws (W.R.S.) after cultivation with the Pleurotas Ostreatus SACCARDO was substituted for wheat bran in the broiler ration. The results of the experiment 1 and 2 obtained were summerized as follows; 1. The content of C. protein in the W.R.S. showed 1.5% higher value than that in the rice straw. No change was detected in the content of C. fat. However the content of C. fiber and N.F.E in W.R.S. decreased in comparision with those of raw rice straw. 2. The treated groups were inclned to rapid gain of body weight, especially the 4% W.R.S. group had been showed significatly higher value of gain than the control and 6% treated groups (p＜0.05 ). 3. No significant differences were observed in the amount of feet intake among experimental groups, even if the treated groups showed slightly higher intake than control group. 4. The treated groups in W.R.S. were inferior to the control group in feed intake but there were no significant differences. 5. The methionine in W.R.S. was the only amino acid which contained similar quantity of wheat brans. 6. To extend the amount of W.R.S. in broiler ration the 6% of W.R.S. was substituted for wheat bran and methionine mixture was added. No significance differences had been showed in weight gain, feed intake and feed efficiency between control and treated groups. Even though the treated groups showed more feed intake and lower weight gain in comparision with control group. 7. The methionine added group showed adverse effect in economics of production (p＜0.01) because of high cost of the methionine mixture, Therefore less than. 6% of the WRS could be substituted for wheat bran. According to the results of the experiment 1 and 2 it could be concluded that maximum use of the W.R.R. as substitute for wheat bran was less than 4% of the ration.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.363-367
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• 2006

We synthesized new blue and bluish green emitting materials by using fully substituted ethylene moieties. Multi-layered EL devices were fabricated with synthesized materials and evaluated in terms of emission color and luminescence efficiency. BPBAPE[EML 4] having high $T_g$ of $155^{\circ}C$ showed luminance and power efficiency of 10.33cd/A and 4.0 lm/W without any doping agent. BTBPPA[EML 5] exhibited 5cd/A and 1.67lm/W efficiency with blue CIE value of (0.165, 0.195).

• Journal of the Korean Ceramic Society
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• v.20 no.3
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• pp.227-235
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• 1983

The dielectric and piezoelectic properties in which $(Zr_{0.52} Ti_{0.48})^{+4}$ ions of $Pb(Zr_{0.52} Ti_{0.48})O_3$ are partially substituted for $W^{+6}$ ions were studied. $ZrTiO_4$ was made by coprecipitation. The specimens of disc shape were sintered respectively at 1180$^{\circ}$to 130$0^{\circ}C$ at an intervals of 2$0^{\circ}C$ for 1 hour. The optimum sintering temperature were found to be between 126$0^{\circ}C$ and 128$0^{\circ}C$. PZT solid solutions sintered had the tetragonal structure with c/a=1.025$\pm$0.005 and theoretical densities incre-ased from 8.02 to 8.17g/cm3 with increasing the amount of the partial substitution of $(Zr_{0.52} Ti_{0.48})^{+4}$ ion for $W^{+6}$ ion The grain size and curie temperature decreased with increasing the amount of $WO_3$ while the dielectric constant increased. When $(Zr_{0.52} Ti_{0.48})^{+4}$ ion was substituted for 1 mole% of $W{+6 ]$ion the planar coupling coefficient$(K_P)$ was as high as 0.58 But as the amount of $WO_3$ increased the mechanical quality factor(Qm) decreased considerably.