• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.6
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• pp.246-251
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• 2001

The $[(Pb_{1-x}$La_{2x/3})TiO_3$, X=0.2] powder was synthesized by the hydrothermal method, and their sintering and dielectric properties according to Mn additive were examined. The relative density of sintered PLT specimen at $1150^{\circ}C$ for 5 hrs with Mn 0.02 mol% additive was 96.7%. The dielectric properties of sintered PLT specimen were changed by content of Mn and increacement of sintering temperature. Dissipation factor was improved by increasing of measuring temperature. Curie temperature of sintered PLT specimens was decreased with increasing of Mn additive.

• Korean Journal of Materials Research
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• v.17 no.2
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• pp.100-106
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• 2007

The effects of $MgO-P_2O_5$ based sintering additive on the microstructure and material and biological properties of hydroxyapatite $(HAp,\;Ca_{10}(PO_4)_6(OH)_2)$ ceramic were investigated using XRD, SEM and TEM techniques. The $MgO-P_2O_5$ sintering additive improved the material properties and increased the grain size in the sintered HAp bodies. As the content of sintering additive increased over 4 wt%, a small amount of the HAp phase was decomposed and transformed to ${\beta}-TCP$. In the 2 wt% $MgO-P_2O_5$ content HAp sintered body, the maximum values of density and hardness were respectively about 3.10 gm/cc and 657 HV. However, the maximum fracture toughness in the HAp body containing 8 wt% $MgO-P_{2}O_{5}$ was about $1.02MPa{\cdot}m^{1/2}$ due to the crack deflection effect. Human osteoblast like MG-63 cells and osteoclast like raw 264.7 cells were well grown and fully covered all of the HAp sintered bodies. The osteoblast cells were grown with spindle-shaped and the osteoclast cells had a grape-like round shape.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.58-67
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• 2000

This study was carried out to acquire basic data necessary for the use of non-wood pulp. Various chemical pulping methods for rice straw to achieve higher yield, lower Kappa No. were investigated and then the physical properties of various pulps were tested. The results of this study were as follows: When various chemical pulps (Soda, Soda-AQ, Soda-$H_2O_2$, Soda-$Na_2S_2$, AS, AS-AQ, AS-$Na_2S_2O_3$, AS-$Na_2S_2O_4$, Kraft) were produced with rice-straw, the pulps with the highest yield and lowest Kappa No. were obtained with Soda-$Na_2S_2$and AS-$Na_2S_2O_4$pulps. For the breaking length, Soda and Soda-additive pulps(7.5~9.2km) were better than AS and AS-additive pulps(6.2~8.1km). Similarly, for the burst index, Soda and Soda-additive pulps(6.0~7.0 kPa.$m^2$/g) were better than AS and AS-additive pulps(4.5~6.3 kPa.m$^2$/g). But the tear index was showed 21.8-30.9 mN.$m^2$/g with a little different between pulping methods.

• Journal of the Korean Ceramic Society
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• v.20 no.1
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• pp.49-54
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• 1983

The main object of this study is to investigate the effect of Al powder as an additive on the sintering of calcined alumina comparing with that of calcined alumina alone. The degree of Al oxidation is calculated by measuring the weight increase during the firing Water absorption bulk density and compressive strength of the $Al_2O_3+Al$ system at each temperature are compared with those of $Al_2O_4$ alone. The $Al_2O_3+Al$ system shows better physical propeties than Al2O3 alone and it seems by the SEM observation that the fine oxidized Al particles(fine $Al_2O_3$ particles submicron unit) fill the interstices of the original $Al_2O_3$ par-ticles and thus result in the well-close-packed arrangement of the particles.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.2
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• pp.178-183
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• 2002

The effects of Dy$_2$O$_3$and Er$_2$O$_3$addition on the electromagnetic properties of Mn-Zn ferrite were investigated in the doping concentration range from 0.05 wt% to 0.25 wt%. All samples were prepared by standard fabrication of ferrite ceramics. The XRD patterns of sample were observed spinel and secondary phase. The densities of sample were showed nearly constant values. As the increased additive, electrical resistivity, initial permeability and real component of the series complex permeability increased with setting limits each other. Excess doped with Dy$_2$O$_3$ and Er$_2$O$_3$, those values decreased. The maximum electrical resistivity was observed with 0.15 we% and initial permeability was observed with 0.05 wt%. Magnetic loss decreased with additive and then increased in proportion to increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.960-966
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• 2004

On the bases of the results from "Additive Coating of BaTiO$_3$ Powder using Sol Coating Method I", experimental condition was defined. Representative additives for BaTiO$_3$, that is to say, Mg, Ca and Mn were experimented. The sources of the metal ion were used by organometal complex. As added it, the stability of BaTiO$_3$ sol was evaluated. Mg and Ca were stable, however, The solubility limit of Mn-ATH was 0.05 mol ratio in Mn-ATH/sol. The solubility limit of Mg ion in BaTiO$_3$ was lower than 2 mol%. From the x Ray diffraction patterns, lattice parameters were different with temperature and additives, because the solubility of metal ion was varied in BaTiO$_3$. The dielectric constant of BaTiO$_3$ powders which coated with the 1.5 mol% Mg and calcined at 1200$^{\circ}C$ was increased with 20%.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.107-109
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• 2003

This paper was to measure the structure, piezoelectric properties of $0.03Pb(Mg_{0.5}W_{0.5})O_3$ - $0.12Pb(Sb_{0.5}Nb_{0.5})O_3$ - $0.85Pb(Zr_{0.52}Ti_{0.48})O_3$ + $0.5[wt%]MnO_2$ ceramics dropped with additive CuO after manufacturing the specimens with a general method. It is shown that X-ray diffraction pattern variation of lines (211) have tendency to move minutely by addition of additive CuO. According to dropping with Cu, the dielectric constant at 20[$^{\circ}C$] reduced to CuO 3.0[wt%]. In case of sintering at 1050[$^{\circ}C$], dielectric constant was maximum value 623.59 at CuO 1.0[wt%]. Dielectric loss was maximum value 2.7[%] at Cu 2.0[wt%] in case of sintering at 1050[$^{\circ}C$].

• Journal of the Korean Ceramic Society
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• v.53 no.6
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• pp.712-718
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• 2016

In this study, we investigate the effect of the$Li_3BO_3$ additive on the densification and ionic conductivity of garnet-type $Li_7La_3Zr_2O_{12}$ solid electrolytes for all-solid-state lithium batteries. We analyze their densification behavior with the addition of $Li_3BO_3$ in the range of 2-10 wt.% by dilatometer measurements and isothermal sintering. Dilatometry analysis reveals that the sintering of $Li_7La_3Zr_2O_{12}-Li_3BO_3$ composites is characterized by two stages, resulting in two peaks, which show a significant dependence on the $Li_3BO_3$ additive content, in the shrinkage rate curves. Sintered density and total ion conductivity of the system increases with increasing $Li_3BO_3$ content. After sintering at $1100^{\circ}C$ for 8 h, the $Li_7La_3Zr_2O_{12}-8$ wt.% $Li_3BO_3$ composite shows a total ionic conductivity of $1.61{\times}10^{-5}Scm^{-1}$, while that of the pure $Li_7La_3Zr_2O_{12}$ is only $5.98{\times}10^{-6}Scm^{-1}$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.5
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• pp.188-192
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• 2005

High $T_c(Y_{0.5}Nd_{0.25}Sm_{0.25})Ba_2Cu_3O_y[(YNS)-123]$ superconductors with/without $CeO_2$ additive were systematically investigated by the zone melt growth process in air. Cylindrical green rods of (YNS)-123 oxides were fabricated by cold isostatic pressing (CIP) method using rubber mould. A sample prepared by this method showed well-textured microstructure, and $(Y_{0.5}Nd_{0.25}Sm_{0.25})_2BaCuO_5[(YNS)211]$ nonsuperconducting inclusions were uniformly dispersed in large $(Y_{0.5}Nd_{0.25}Sm_{0.25})Ba_2Cu_3O_y$[(YNS)123] superconducting matrix. In this study, optimum melting temperature and growth rate were $1100^{\circ}C$ and 3 mm/hr, respectively. The directionally melt-textured (YNS)-123 sample with $CeO_2$ additive showed an onset critical temperature $(T_c)\;T_c{\geq}93K$ and sharp superconducting transition.

• 전기의세계
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• v.31 no.6
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• pp.445-449
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• 1982

This Paper describes the influence of additive concentrations and sintering temperature on the surge protection performance in ZnO ceramic varistors. It is found from the experiments that the metal-oxide semiconductors based oi ZnO with an additive incorporation of 0.50% molx(Bi$\_$2/O$\_$3/+MnO+CoO+Cr$\_$2/O$\_$3/+2Sb$\_$2/O$\_$3/) and sintered at 1250.deg. C present excellent V-I characteristics in view of transient surge suppression. Gapless arrester element with aluminum electrodes shows also good reliability against impulse shock and marks a low voltage clamping ratio(V$\_$1KA/V$\_$1mA/<2.0) compared with the conventional SiC varistors.