• 한국세라믹학회지
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• 제36권12호
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• pp.1369-1373
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• 1999

• 펄프종이기술
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• 제44권5호
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• pp.32-38
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• 2012

This study was carried out to elucidate the potential in substitution of SB latex with eco-friendly starch based bio-binder as a coating binder. The part of SB latex in coating color of pre- and top layer was substituted with starch based bio-binder in order to evaluate the characteristics of coating color and coated paper, and printability. The viscosity and water retention of coating color were increased by substitution of SB latex with starch based bio-binder. Roughness of coated paper was increased by substitution with starch based bio-binder, although there was not significant changes in roughness when SB latex is used as a binder in pre-coating color. Brightness and whiteness of coated paper were not affected, but opacity and print mottle were improved by substitution with starch based bio-binder. The interesting result observed was that dry-pick did not affected significantly, and ink set-off was improved by starch based bio-binder. It is expected that starch based bio-binder can be commercialized if the systematic further research works are carried out.

• 펄프종이기술
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• 제46권6호
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• pp.63-70
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• 2014

Part of SB latex in pre-coating color was substituted with newly developed starch-based bio-binder in order to investigate the effect of starch-based bio-binder in pre-coating color on the properties of coating color and coated paper. Smoothness and gloss of coated paper were decreased with the increase of bio-binder substitution ratio. Brightness and whiteness did not show the significant changes, but stiffness was improved with bio-binder. Ink set-off, dry-pick and wet pick were decreased with the increase of bio-binder substitution ratio. In general, when all SB latex is substituted with bio-binder, ink set-off, dry- and wet-pick were deteriorated. However, it was found that if the bio-binder substitution ratio is controlled below 50%, similar qualities with coated paper manufactured by the use of SB latex binder can be obtained.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.124-128
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• 2000

The high Tc phase disappeared and low Tc phase increased in the substitution of transistion elements for Bi ions. The high Tc phase decreased in the substitution of Si and Sn for Bi ions. The high Tc phase increased in the substitution of Sb, As and P Which Were the same group of Bi for Bi ions. The substitution of P ions was the most effective and then the high Tc phase was formed in large quantity by replacing Bi ions with 30%of P ions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.255-258
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• 2000

In this study, the structural, dielectric and piezoelectric properties of Pb[(Sb$\sub$1/2/Nb$\sub$1/2/)$\sub$x/- (Ni$\sub$1/3/Nb$\sub$2/3/)$\sub$0.15-x/- (Zr,Ti)$\sub$0.85/]O$_3$(x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) ceramics is investigated as a function of Pb(Sb$\sub$1/2/Nb$\sub$1/2/)O$_3$ (abbreviated PSN) substitution. With the increase of PSN substitution, the crystal structure is transO$_3$formed from the tetragonal phase to the rhombohedral phase and the grain size is decreased abruptly. The curie temperature is decreased with the PSN substitution. The dielectric constant is increased with the PSN substitution and maximum value of 2290 is obtained at 4mol% PSN. With the PSN substitution, the coercive field is increased and the remnant polarization is decreased. The Electromechanical coupling factor(k$\sub$p/) Is showed the highest value of 0.622 at lmol% PSN and the mechanical quality factor(Q$\sub$m/) is decreased abruptly with the PSN substitution.

• 한국전기전자재료학회논문지
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• 제14권5호
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• pp.356-361
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• 2001

The structureal, dielectric and piezoelectric properties of Pb[(Sb$\_$1/2/Nb$\_$1/2/)$\_$x/-(Ni$\_$1/3/Nb$\_$2/3/)$\_$0.15-x/-(Zr$\_$y/Ti$\_$1-y/)$\_$0.85/]O$_3$(x=0∼0.05, y=0.47∼0.52) ceramics were investigated with the substitution of Pb(Sb$\_$1/2/Nb$\_$1/2/)O$_3$(abbreviated PSN) and the Zr/Ti ratio. At Zr/Ti ratio of 50/50, tetragonality was decreased and grain size abruptly decreased with the increase of PSN substitution. Curie temperature was decreased and dielectric constant increased with the substitution of PSN. The coercive field increased and remnant polarization decreased with the substitution of PSN. Electromechanical coupling factor(k$\_$p/) showed the highest value of 0.622 at 1mol% PSN, but mechanical quality factor(Q$\_$m/) showed the minimum value at that composition. Dielectric constant and electromechanical coupling factor with the Zr/Ti ratio showed maximum values at Zr/Ti ratio of 50/50 and mechanical quality factor showed minimum values near the Zr/Ti ratio of 50/50.

• 한국재료학회지
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• 제20권6호
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• pp.326-330
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• 2010

$CoSb_3$ Skutterudites materials have high potential for thermoelectric application at mid-temperature range because of their superior thermoelectric properties via control of charge carrier density and substitution of foreign atoms. Improvement of thermoelectric properties is expected for the ternary solid solution developed by substitution of foreign atoms having different valances into the $CoSb_3$ matrix. In this study, ternary solid solutions with a stoichiometry of $Co_{1-x}Ni_xSb_3$ x = 0.01, 0.05, 0.1, 0.2, $CoSb_{3-y}Te_y$, y = 0.1, 0.2, 0.3 were prepared by the Spark Plasma Sintering (SPS) system. Before the SPS synthesis, the ingots were synthesized by vacuum induction melting and followed by annealing. For phase analysis X-ray powder diffraction patterns were checked. All the samples were confirmed as single phase; however, with samples that were more doped than the solubility limit some secondary phases were detected. All the samples doped with Ni and Te atoms showed a negative Seebeck coefficient and their electrical conductivities increased with the doping amount up to the solubility limit. For the samples prepared by SPS the maximum value for dimensionless figure of merit reached 0.26, 0.42 for $Co_{0.9}Ni_{0.1}Sb_3$, $CoSb_{2.8}Te_{0.2}$ at 690 K, respectively. These results show that the SPS method is effective in this system and Ni/Te dopants are also effective for increasing thermoelectric properties of this system.

• 자원환경지질
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• 제26권3호
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• pp.327-335
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• 1993

자연에는 팔라듐을 주성분으로 하는 백금족광물이 다수 산출되고 있다. 그 중 일부 광물은 독립된 광물로서 결정학적 광물학적 연구가 잘 되어 있는 반면 아직도 광물로서의 특성이 완전하게 규명되지 못한 경우도 상당수가 있다. 따라서 이 연구에서는 팔라듐-안타몬-테루르 성분계를 택해 이 3성분계에서의 상관계를 $1000^{\circ}C$, $800^{\circ}C$, $600^{\circ}C$에서 각각 연구하고 이들 연구결과를 천연광물을 보다 체계적으로 규명 보완하는데 적용시키는 것을 그 연구 목적을 두었다. 합성실험을 위해 순수한 원소물질을 정량적으로 혼합시킨 후 실리카 튜브에 넣고 진공상태에서 밀봉하였다. 전기 고온로에서 가열반응시킨 시료는 얼음물을 이용해 급냉시켰으며 반응물은 반사현미경, 전자현미분석, X선 회절법 등으로 분석하였다. $1000^{\circ}C$에서 안정한 고체로는 Pd, $Pd_{20}Sb_7$, $Pd_8Sb_3$, $Pd_{31}Sb_{12}$, $Pd_5Sb_2$가 있다. $800^{\circ}C$에서는 $Pd_5Sb_3$, PdSb, $Pd_8Te_3$, $Pd_7Te_3$, $Pd_{20}Tc_7-PdSb_7$ 완전고용체가 추가로 존재한다. $600^{\circ}C$에서는 $PdSb_2$, $Pd_{17}Te_4$, $Pd_9Te_4$, PdTe, $PdTe_2$, $Sb_2Te_3$, Sb, 그 밖에 PdSb-PdTe와 PdTe-$PdTe_2$ 고용체가 다시 안정한 고체 화합물로 추가된다. 모든 고체 화합물이 Sb와 Te간의 원소치환에 의해 고용체를 이루고 있으며 그 고용한계의 범위는 생성온도에 따라 변한다. Pd-Sb화합물에서 안티몬(Sb)를 치환하는 테루르(Te) 최대 치환범위(at.%)는 $Pd_8Sb_3$에서 44.3, $Pd_{31}Sb_{12}$에서 52.0, $Pd_5Sb_2$에서 46.2이며 그 최대 치환현상은 $800^{\circ}C$에서 일어난다. $Pd_5Sb_3$와 $PdSb_2$에서의 최대 치환은 $600^{\circ}C$에서 일어나며 그 정도는 각각 15.3, 68.3이다. Pd-Te화합물에서 Te를 치환하는 Sb의 최대치(at.%)는 $Pd_8Te_3$가 $800^{\circ}C$에서 34.5, $Pd_7Te_3$, $Pd_{17}Te_4$, $Pd_9Te_4$, $PdTe_2$는 $600^{\circ}C$에서 각각 41.6, 5.2, 19.1로 나타난다. $Pd_9Te_4$, PdTe, $PdTe_2$, $Pd_8Sb_3$, PdSb, $Sb_2Te_3$는 각각 tellurantimony와 일치하며 광학적 결정구조적 성질이 매우 잘 일치한다. 지금까지 등축정계의 Pa3구조를 가지고 있는 것으로 알려진 $PdSb_2$화합물은 Gandolfi camera와 Guinier camera법에 의해 310으로 격자 지수화할 수 있는 $2.035{\AA}$ peak가 일정하게 기록이 되므로 $P2_13$공간군에 속하는 것으로 재평가 된다. Testibiopal1adite의 성분을 가지는 PdSbTe성분의 화합물을 합성하여 X선 회절분석을 실시하면 testibiopalladite의 X선 회절양상과 일치함을 알 수 있다. 이 사실은 testibiopalladite가 등축정계이며 동시에 $P2_13$공간군에 속하는 $PdSb_2-Pd(Sb_{0.32}Te_{0.68})$고용체의 일부분에 속하는 광물임을 알 수 있게 한다. 따라서 현재의 testibiopalladite의 이상화학식인 PdSbTe는 PdTe(Sb, Te)로 바뀌어져야 할 것으로 믿어진다. $Pd_3SbTe_4$로 표현되는 borovskite는 $1000^{\circ}{\sim}600^{\circ}C$의 온도범위에서는 존재하지 않음을 알 수 있다.

• 대한금속재료학회지
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• 제56권11호
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• pp.822-828
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• 2018

P-type Ce/Yb-filled skutterudites were synthesized, and their charge transport and thermoelectric properties were investigated with partial double filling and charge compensation. In the case of $(Ce_{1-z}Yb_z)_{0.8}Fe_4Sb_{12}$ without Co substitution, the marcasite ($FeSb_2$) phase formed alongside the skutterudite phase, but the generation of the marcasite phase was inhibited by increasing Co concentration. The electrical conductivity decreased with increasing temperature, exhibiting degenerate semiconductor behavior. The Hall and Seebeck coefficients were positive, which confirmed that the specimens were p-type semiconductors with holes as the major carriers. The carrier concentration decreased as the concentration of Ce and Co increased, which led to decreased electrical conductivity and increased Seebeck coefficient. The thermal conductivity decreased due to a reduction in electronic thermal conductivity via Co substitution, and due to decreased lattice thermal conductivity via double filling of Ce and Yb. $(Ce_{0.25}Yb_{0.75})_{0.8}Fe_{3.5}Co_{0.5}Sb_{12}$ exhibited the greatest dimensionless figure of merit (ZT = 0.66 at 823 K).

• 한국세라믹학회지
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• 제37권4호
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• pp.395-401
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• 2000

In this study, we chose the basic composition which indicated the best electrical properties by change of x content(0, 0.05, 0.1, 0.15, 0.2, 0.25 mol respectively) in xPb(Mn1/3Sb2/3)O3-(1-x)Pb(Zr0.52Ti0.48)O3 ceramics. And we substituted Cd2+ for Pb2+ site, then observed the sintering behavior, microstructure and electrical propertties according to the various sintering temperature. The basic composition was the 0.05PMS-0.95PZt, and it showed single perovskite phase and excellent properties. In case of Cd2+ substitution, we were able to sinter at 90$0^{\circ}C$ which was lower than conventional sintering temperature(1200~130$0^{\circ}C$). Especially, when the 2mol% substituted PMS-PZT specimens were sintered at 90$0^{\circ}C$ for 2h, we obtained the p=7.6g/㎤, kp=56%, Qm=520 and made sure of a position of Cd2+ substitution by observing lattice parameter, phase transition temperature. From this results, we could infer that because Cd2+ substituted fro A-site, low temperature sintering of Cd2+ substituted PMS-PZT without any loss of electrical properties shows its applicability for the piezoelectric ceramic transformer.