• 한국표면공학회지
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• 제46권2호
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• pp.87-92
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• 2013

Viscosities of $LaCl_3$-CsCl binary melts were measured by the capillary method over the range of their liquidus temperatures to about 1200 K. The cell constant were determined by using pure water. The results obtained are summerized as follows: Viscosities of melted $LaCl_3$ were decreased with the content of CsCl for all over the composition range of binary melts. Composition versus viscosity relation for the binary melt showed a non-linear relationship from the additivity line and the deviations showed a maximum value at about 60 mol% CsCl. This suggest the existence of the complex ion of $LaCl_4{^-}$ in the melt. Activation energy for the viscous flow of the binary melts decreased monotonously with the increasing content of CsCl after a few increasement till 40 mol% CsCl. All of these results were the resemble with the viscosities of $LaCl_3$-NaCl binary melts.

• 한국표면공학회지
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• 제39권6호
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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.

• 한국표면공학회지
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• 제37권5호
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• pp.301-306
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• 2004

Electric Conductivities of $LaCl_3$-LiCl binary melts have been measured by the Kohlausch bridge method over the range of their liquidus temperatures to about 1200 K. The electric conductivity increases with the content of LiCl for all over the composition range of binary melts. Composition dependence of the electric conductivity and molar conductivity for the binary melt shows a non-linear relation from the additivity line, and the deviations displays a maximum value at about 60 mol % LiCl. This suggest the existence of the complex ion of$ LaCl_{4}^{-}$ in the melt. Activation energy for electric conductivity of the binary melts decrease monotonously with increasing content of LiCl.l.

• 한국표면공학회지
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• 제47권1호
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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.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.166-172
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• 2003

Calcium lactate (CL) prepared from powdered black snail (PBS) or its ashed powder (ABS), was investigated for ideal manufacturing conditions to optimize color, solubility and sensory quality. Based on the amount of PBS and 100 mL lactic acid (LA), the yields of PBS-CL were 300% and 15 g in 10% LA and 260% and 20 g in 20% LA. Yields of ABS-CL based on the amount ABS and 100 mL LA were 400% and 60 g in 10% LA and 329% and 66 g in 20% LA. Both of the yields were decreased with an increase of the LA concentration on the basis of PBS and ABS amounts, but proportionally increased with the increment in the LA concentration on the basis of LA volume. Optimal preparation times of the dehydrated PBS-CL and ABS-CL were, respectively, 4 hr and 5 hr at 10$0^{\circ}C$, 3 hr and 4 hr at 12$0^{\circ}C$, and 1 hr and 2 hr at 15$0^{\circ}C$, which showed shorter time in preparing the dehydrated ABS-CL. PBS-CL and ABS-CL were confirmed to be Ca($CH_3$CHOH$CO_2$)$_2$ by the analysis results of IR and $^1$H-NMR. Calcium contents of the anhydrous PBS-CL and ABS-CL were individually 15.4% (w/w) and 17.3% (w/w) representing 84.2% and 94.5% or each theoretical value. Colors or PBS-CL and ABS-CL were light yellow and light-greenish white each. Solubilities of PBS- CL and ABS-CL in distilled water at pH 3~8 were 5.43 and 6.11 g/100 mL, respectively, which demonstrated higher mean solubilities rather than the 4.74 g/100 mL of standard CL. Solubilities of PBS-CL (3.14~5.03 g/100 mL) and ABS-CL (4.69~6.05 g/100 mL) against soup soy sauce, 3% brine, Soju (Korean distilled liquor), thick soy sauce, grape juice and orange juice were higher than those of standard CL (2.94~5.84 g/100 mL). ABS-CL was believed to have a wide use range due to its low sourness while different applications of PBS-CL in food are expected due to its mild astringent taste and strong savory taste despite its strong bitter taste as estimated by sensory evaluation.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1303-1309
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• 2012

A novel ligand N,N'-(2,6-pyridinedicarbonyl)bis[N-(carboxymethyl)] (L1) was designed and synthesized. Four co-luminescence groups of Sm-La-pyridyl carboxylic acids systems were researched, which are $K_4Sm_{(1-x)}-La_x(L_1)Cl_3{\cdot}y_1H_2O$, $K_4Sm_{(1-x)}La_x(L_2)Cl_3{\cdot}y_2H_2O$, $K_6Sm_{2(1-x)}La_{2x}(L_3)Cl_6{\cdot}y_3H_2O$, $K_4Sm_{(1-x)}La_x(L_4)Cl_3{\cdot}y_4H_2O$. The results indicated the addition of La(III) could sensitize the luminescence of Sm(III) obviously in a certain range, enhancing emission intensity of Sm-pyridyl carboxylic acids relative to the undoped ones. The optimal mole percentages of La(III) in the mixed ions for $L_1$, $L_2$, $L_3$, $L_4$ were confirmed to be 0.6, 0.5, 0.3, 0.6, respectively. The mechanism of the fluorescence enhancement effect was discussed in detail. Furthermore, the binding interaction of $K_4Sm_{0.4}La_{0.6}(L_4)Cl_3{\cdot}5H_2O$ with bovine serum albumin (BSA) have been investigated due to its potential biological activity. The binding site number n was equal to 1.0 and binding constant $K_a$ was about $2.5{\times}10^5\;L{\cdot}mol^{-1}$.

• Korean Chemical Engineering Research
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• 제53권2호
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• pp.145-149
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• 2015

LiCl 용융염에서 희토류 금속을 포함한 $Nd_2O_3-La_2O_3-NiO$ 복합산화물의 전해환원을 통한 $La_{0.5}Nd_{0.5}Ni_5$ 합금제조에 대한 연구를 수행하였다. $Nd_2O_3-La_2O_3-NiO$ 복합산화물은 $1100^{\circ}C$에서 소결시에 $NiNd_2O_4$ (스피넬)과 $LaNiO_3$ (페로브스카이트) 구조가 생성되었다. 스피넬 및 페로브스카이트 구조는 복합산화물의 전해환원 반응속도를 증가시켰다. LiCl 용융염에서 전해환원 반응 동안 $Nd_2O_3-La_2O_3-NiO$ 복합산화물은 Ni, $NiLa_2O_4$ 등의 다양한 중간생성물을 거쳐 $La_{0.5}Nd_{0.5}Ni_5$ 합금으로 환원됨을 확인할 수 있었다. XRD 분석결과를 통해 최종 생성물인 $La_{0.5}Nd_{0.5}Ni_5$의 생성 메카니즘을 제시하였다.

• 한국산학기술학회논문지
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• 제12권2호
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• pp.600-604
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• 2011

본 Czochralski 방법으로 새로운 섬광체인 $LaCl_3:Eu^{2+}$ 결정을 육성하고, 육성된 섬광체의 섬광 특성을 조사하였다. 육성한 $LaCl_3:Eu^{2+}$ 결정 구조는 육방정계로서 $P_63$/m 공간군에 속함을 확인할 수 있었으며, 격자상수는 각각 a = b = $7.48{\AA}$, c = $4.37{\AA}$이었다. 335 nm로 여기시킨 $LaCl_3:Eu^{2+}$ 결정의 발광 스펙트럼 파장 범위는 약 370 ~ 640 nm 이었으며, 중심 파장은 430 nm이었다. 형광 감쇠 곡선은 $2.82{\pm}0.72{\mu}s$의 단일 성분으로 구성되었으며, $^{137}Cs$ 662 keV ${\gamma}$-선에 대한 에너지 분해능은 약 8.8%이었다.

• 대한방사선기술학회지:방사선기술과학
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• 제20권1호
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• pp.65-69
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• 1997

[ $Mg_2SiO_4(La.Ho)$ ] thermoluminescent phosphor was made by putting the $MgCl_2.6H_2O$ and $SiO_2$ and by doping the rare earth element of $LaCl_3.7H_2O$ and $HoCl_3$. The heating rate is $10^{\circ}C/sec$ for the thermoluminescent phosphor. Two peaks are found in the measured $Mg_2SiO_4(La.Ho)$ Tl glow curve at $152^{\circ}C$ and $205^{\circ}C$ when the heating rate is $5^{\circ}C/sec$. The peak value at $205^{\circ}C$ is the most sensitive to X-ray among the glow peaks. The activation energy of the main peak has been estimated by the peak shape method. The estimated activation energies for Ho and La are $0.52{\sim}1.77\;eV$ respectively.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 춘계총회 및 제22차 학술발표회
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• pp.122-122
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• 2003

다슬기의 분말(PSB)과 그 회화분(ASB)으로부터 체내 흡수력이 높은 젖산칼슘의 제조조건과 색상, 용해도 및 관능적 품질을 조사하였다. PSB로부터 제조한 젖산칼슘(PSB-CL)의 PSB 및 젖산 100 mL에 대한 수율은 젖산농도가 10%일 때는 300% 및 15 g, 20%일 때는 260% 및 20 g이었으며, ASB로 제조한 젖산칼슘(ASB-CL)의 ASB 및 젖산 100 mL에 대한 수율은 10% 젖산에서는 400% 및 60 g, 20% 젖산에서는 329% 및 66 g으로 원료량을 기준으로 하였을 때는 다같이 젖산농도의 증가에 따라 감소하였으나 젖산의 부피를 기준으로 하였을 때는 젖산농도의 증가에 따라 증가하였다. Dehydated PSB-CL 및 ASB-CL 제조의 적정온도와 시간은 10$0^{\circ}C$에서는 각각 4 및 5시간, 12$0^{\circ}C$에서는 3 및 4시간, 15$0^{\circ}C$에서는 1 및 2시간으로 ASB-LA의 경우가 짧았다. IR 및 H-NMR spectrum의 분석결과 PBS-LA와 ASB-LA의 구조는 Ca($CH_3$CHOH$CO_2$)$_2$임이 확인되었다. 무수 PSB-CL 및 ASB-CL의 칼슘함량은 각각 15.4%(w/w)와 17.3%(w/w)로 이론 값의 각각 84.2%와 94.5%를 나타내었으며, 미량의 Fe, Na, Mn Zn을 함유하였다. PBS-CL와 ASB-CL의 색상은 각각 연한 황색과 연녹색을 지닌 백색을 띠었다. pH 3~8로 조정한 증류수에서 PSB-CL과 ASB-CL의 평균 용해도는 각각 5.43 g/100 mL 및 6.11 g/100 mL로 standard CL의 4.74 g/mL에 비하여 높았다. 국간장을 제외한 대부분의 액체식품(3% 소금물, 소주, 진간장, 국간장, 포도주스 및 오렌지주스)에서의 용해도는 PSB-CL(3.14~5.03 g/100 mL)과 ASB-CL(4.69~6.05 g/100 mL)이 standard CL(2.94~5.84 g/100 mL)에 비하여 높았다. 관능검사 결과, ASB-CL은 신맛이 낮아 사용범위가 높은 것으로 평가되었으며 PSB-CL는 쓴맛은 높으나 떫은맛이 낮고 구수한 맛이 강하여 식품에의 응용이 기대된다.