• Carbon letters
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• v.10 no.1
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• pp.38-42
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• 2009

This study aims to find a correlation between XRD and Raman result of the oxidized high modulus carbon fibers as a function of its oxidation degrees, and compare with the isotropic carbon fiber reported early. La of the high modulus carbon fiber prepared by oxidation in carbon dioxide gas have been observed using laser Raman spectroscopy. The basic structural parameters of the fibers were evaluated by XRD as well. The La of the original high modulus carbon fibers were measured to be 144 ${\AA}$ from Raman analysis and 135 ${\AA}$ from XRD analysis. La of the 92% oxidized fiber were 168 ${\AA}$ by using Raman and 182 ${\AA}$ by using XRD. There was some correlation between the La value obtained from Raman and XRD. However the La value changes of the high modulus carbon fiber through whole oxidation process showed opposite tendency compare with the isotropic carbon fiber because of the fiber structure basically.

• Journal of the Korean institute of surface engineering
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• v.47 no.1
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• pp.48-52
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• 2014

Electric conductivities of $LaCl_3$-KCl binary melts have been measured by the Kohlausch bridge method over the range from their liquidus temperatures to about 1280 K. The electric conductivity increased with the content of KCl for all over the composition range of binary melts. The composition dependence of the electric conductivity and molar conductivity for the binary melt showed a non-linear relation from the additivity line, and the deviation showed a maximum value at about 60 mol.% KCl. The deviation implies the existence of complex ion of $LaCl^{4-}$ in the melt. Activation energy for electric conductivity of the binary melts decreased monotonously with increasing content of KCl.

• Fibers and Polymers
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• v.3 no.2
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• pp.60-67
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• 2002

In the present study, the fluorescence behavior ova phenylethynyl-terminated imide (LaRC PETI-5) resin, a bismaleimide (BMI) resin, and various LaRC PETI-5/BMI blends with different blend compositions has been characterized as a function of heat-treatment temperature, using a steady-state fluorescence technique with a front-face illumination method far solid-state films. It is observed that there are distinguishable changes in the spectral shape, size, and position of fluorescence with varying heat-treatment temperature in the pure and blend samples. The result is qualitatively explained in terms of charge transfer complex formation as well as microenvironmental change with local mobility and viscosity occurring in the LaRC PETI-5, BMI, and their blends during the cure process. The result also implies that a steady-state fluorescence technique may be a useful tool to understand the processing conditions of polyimides and their blends in the film form on the basis of their thermo-photophysical responses.

• Journal of the Korean institute of surface engineering
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• v.39 no.6
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• pp.282-287
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• 2006

Viscosities of $LaCl_3-NaCl$ binary melts were measured by the capillary method over the range of their liquidus temperatures to about 1200K. The cell constant were determined by using pure water. The results obtained are summerized as follows: Viscosities were decreased with the content of NaCl for all over the composition range of binary melts. Composition - viscosity relation for the binary melts show a non-linear from the additivity line and the deviations shows a maximum at about 60 mol% NaCl. This suggests the existence of the complex ion of $LaCl_4^-$ in the melt. Activation energy for viscous flow of the binary melts decrease monotonously with the increasing content of NaCl.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.48-51
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• 2002

In order to study the reaction behavior of bovine holo- and apo-$\alpha$-lactalbumin ($\alpha$-La) during heat treatment at 65~10$0^{\circ}C$, the samples were analysed by first (ID)-and second-dimensional (2D) native-polyacrylamide gel electrophoresis (Native-PAGE) and sodium dodecylsulfate (SDS)-PAGE. When bolo-$\alpha$-La or apo- $\alpha$ -La were heated, they formed non-native, monomers, dimers and trimers. The apo-$\alpha$-La was more heat-sensitive than holo-$\alpha$-La. The monomers seemed to have the same composition as the native $\alpha$-La, but many of the disulfide bonds could be non-native.

• Korean Journal of Veterinary Research
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• v.32 no.4
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• pp.641-647
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• 1992

This study was conducted to determine the serum antibodies against toxoplasma in the artificially infected dogs, pet and street dogs by latex agglutination (LA) and indirect fluorescent antibody (IFA) test. LA test was carried out with commercial Toxo-MT kit (Eiken chemical Co.) and IFA test was carried out with rabbit-anti-dog IgG labelled with FITC (Cappel Co.) and toxo-antigen slides prepared in laboratory. The results obtained were as follows ; 1. Antibodies to Toxoplasma gondii in the artificially infected dogs were detected firstly at the Day 8 in IFA and Day 9 in LA test after inoculation. Positive antibody reactions by these tests were declined gradually afterward but maintained up to 12 weeks. 2. In LA test serum antibody titers in 310 test sera were shown as 10 cases(32%) in 1 : 32.5(1.0%) in 1 : 64, 4(1.3%) in 1 : 128 and 2(0.7%) in 1 : 256. In IFA test serum antibody titers 310 test sera were shown as 17 cases(5.5%) in 1 : 64, 8(2.6%) in 1 : 128 and 5(1.6%) in 1 : 256. 3. In the total of 310 sera from pet and street dogs toxoplasma antibody positive rates were 21 cases (6.8%) by LA and 30 cases (9.7%) by IFA test and the positive detection rates between these two groups by LA and IFA test were not significant(p<0.05). 4. In the total of 115 sera from pet dogs toxoplasma antibody positive rates were 12 cases(10.4%) by LA and 15(13.0%) by IFA test. And in the 195 street dogs the positive rates were 9 cases(4.6%) by LA and 15(7.7%) by IFA test. Also, the positive detection rates between these two groups by LA and IFA test were not significant(p<0.05). 5. Agreement of reactivity between LA and IFA test for 310 sera was 91.3% in total of 283 cases consisting of 12 cases(3.9%) of both LA and IFA positive and 271 cases(87.4%) of LA and IFA negative. 6. LA test was almostly equivalent to the IFA test in producibility and proved to be a simple tool for the screening of toxoplasma antibody in laboratory.

• Journal of the Korean Society of Costume
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• v.65 no.3
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• pp.28-46
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• 2015

The aim of this research is to classify the concept expressed in the mobility of la diff${\acute{e}}$rant play, and supplement logic, which is process of the changeability of fashion style. The specific research questions are as follows: first question deals with the relationship between changeability and la diff${\acute{e}}$rant images, and how la diff${\acute{e}}$rant images are divided by each phase and how their circumduction play is proceeded. The second question is about the important features of the mobility of la diff${\acute{e}}$rant play and the method of la diff${\acute{e}}$rance play. The last topic of this study covers the supplement logic and the condition, and how supplement logic has been applied in the process of changeability of fashion style. This paper deploys a qualitative research method providing a systematic review of the previous studies. To sum it up, the mobility of la diff${\acute{e}}$rant play is the root of power, which is controlling the changeability of fashion style, and the objective of the play is to outline new la diff${\acute{e}}$rant images through spatialization of time. In addition, supplement logicis the method of la diff${\acute{e}}$rant play and the purpose of the logic is to harmonize 'ultimate la diff${\acute{e}}$rant image', which is the phenomenological construction stratum in the state of sub-conscious changeability, and 'immediate la diff${\acute{e}}$rant image', which is the structural construction level stratum in the state of external changeability. This research proves that the intrinsic attribute of changeability is contained the mobility of la diff${\acute{e}}$rant play and supplement logic.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.418-427
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• 1997

The effect of $La_2O_3$ as a dopant on the microstructure structure, crystal structure and electrical properties was studied. $0.05Pb(Sn_{0.5}Sb_{0.5})O_3＋0.11PbTiO_3＋0.84PbZroO_3＋0.4Wt%MnO_2$ (=0.05PSS ＋0.11PT＋0.84PZ+0.4wt%$MnO_2$) systems doped with 0, 0.1, 0.3, 0.5, 0.7, 1, 3, 5 mole% $La_2O_3$ were fabricated and investigated sintering density, crystal structure and micro-structure. The sintered 0.05PSS＋0.11PT＋0.84PZ+0.4wt%$MnO_2$ system doped with $La_2O_3$showed sintering density of the range of 7.683 g/㎤ of 0 mole% doping to 7.815 g/㎤ of 0 mole% doping. The average grain sizes in the range of 0 to 5 mole% $La_2O_3$were decreased from 9.0 $\mu\textrm{m}$ to 1.3 $\mu\textrm{m}$. X-ray diffraction investigation of sintered bodies showed that solid solutions were formed between 0.05PSS＋0.11PT＋0.84PZ+0.4wt%$MnO_2$ system and $La_2O_3$ in the range of 0 to 1 mole% but second phases were formed in case of 3, 5 mole%. Dielectric constants at 1 kHz were increased with 0 to 3 mlole% $La_2O_3$ before and after poling at the condition of 5 $KV_{DC}$/mm at $120^{\circ}C$ or $140^{\circ}C$ during 20 minutes. All Dielectric losses at 1 kHz were less than 1%, Curie temperatures were $208^{\circ}C$, $183^{\circ}C$, $152^{\circ}C$ and $127^{\circ}C$ at 0, 0.5, 1, 3 mole% $La_2O_3$ respectively. The values of $K_p$ were increased from 0 to 3 mole% $La_2O_3$ after poling at condition of 5 $KV_{DC}$mm at the condition of $120^{\circ}C$ or $140^{\circ}C$. The case of 0.7 mole% $La_2O_3$doped 0.05PSS＋0.11PT＋0.84PZ+0.4wt%$MnO_2$ system showed $K_p$ of 14.5% by poling at $140^{\circ}C$ during 20 minutes.

• Journal of Powder Materials
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• v.19 no.6
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• pp.429-434
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• 2012

With increase in operating temperature of gas turbine for higher efficiency, it is necessary to find new materials of TBC for replacement of YSZ. Among candidate materials for future TBCs, zirconate-based oxides with pyrochlore and fluorite are prevailing ones. In this study, phase structure and thermal conductivities of $(La_{1-x}Gd_x)_2Zr_2O_7$ oxide system are investigated. $(La_{1-x}Gd_x)_2Zr_2O_7$ system are comprised by selecting $La^{3+}/Gd^{3+}$ as A-site ions and $Zr^{4+}$ as B-site ion in $A_2B_2O_7$ pyrochlore structures. With powder mixture from each oxide, $(La_{1-x}Gd_x)_2Zr_2O_7$ oxides are fabricated via solid-state reaction at $1600^{\circ}C$. Either pyrochlore or fluorite or mixture of both appears after heat treatment. For the developed phases along $(La_{1-x}Gd_x)_2Zr_2O_7$ compositions, thermal conductivities are examined, with which the potential of $(La_{1-x}Gd_x)_2Zr_2O_7$ compositions for TBC application is also discussed.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.481-489
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• 1996

D,L-lactide (2-LA) was copolymerized with ${\beta}$-methyl-${\delta}$-valerolactone (MVL) using tetraphenyltin as a catalyst and the properties of the copolymers were investigated. The composition of the repeating unit of lactic acid in the copolymers was higher than that in the monomer feeds. The composition of the lactic acid unit in the copolymers decreased with increasing copolymerization time. The yield and the molecular weight of the copolymer increased with increasing 2-LA in the feed composition. These results suggest that the reactivity of 2-LA is larger than that of MVL. The number average molecular weight was in the range of 54,000 to 63,000 and the polydispersity index was in the range of 1.7 to 2.1. The copolymers did not show melting point, but glass transition temperature. The degradable tendency of the copolymers with lipase was almost equal to that of L-lactide-MVL copolymer.