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Effects of Cd substitution on the superconducting properties of (Pb0.5Cu0.5-xCdx)Sr2(Ca0.7Y0.3)Cu2Oz

  • Lee, Ho Keun;Kim, Jin
    • Progress in Superconductivity and Cryogenics
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    • v.20 no.2
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    • pp.24-28
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    • 2018
  • To understand the effects of Cd substitution for Cu, $(Pb_{0.5}Cu_{0.5-x}Cd_x)Sr_2(Ca_{0.7}Y_{0.3})Cu_2O_z$ (x = 0 ~ 0.5) compounds were synthesized and the structural and superconducting properties of the compounds were characterized. Resistivity data revealed that superconducting transition temperature rises initially up to x = 0.25 and then decreases as the Cd doping content increases. Room-temperature thermoelectric power decreases at first up to x = 0.25 and then increases with higher Cd doping content, indicating that the change in $T_c$ is mainly caused by the change in the hole concentration on the superconducting planes by the Cd doping. The non-monotonic dependence of the lattice parameters and the transition temperature with Cd doping content is discussed in connection with the possible formation of $Pb^{+2}$ ions and the removal of excess oxygen caused by Cd substitution in the charge reservoir layer. A correlation between transition temperature and c/a lattice parameter ratio was observed for the $(Pb_{0.5}Cu_{0.5-x}Cd_x)Sr_2(Ca_{0.7}Y_{0.3})Cu_2O_z$ system.

The effect of $Ba^{+2}$ shortage on microwave dielectric characteristics of $Ba_{1-x}$ $(Z $n_{1/3}$T $a_{2/3}$ $O_3$ ceramics (B $a^{+2}$의 결핍에 따른 Ba(Z $n_{1/3}$T $a_{2/3}$ $O_3$ 세라믹스의 고주파 유전특성에 관한 연구)

  • 이문길;이두희;윤현상;김준한;홍재일;박창엽
    • Electrical & Electronic Materials
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    • v.7 no.5
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    • pp.403-408
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    • 1994
  • Dielectric and structural properties of $Ba_{1-x}$(Z $n_{1}$3/T $a_{2}$3/) $O_{3}$+1 mol% Mn $O_{2}$ (x=0, 0.01, 0.02, 0.03, 0.04) ceramics was investigated at microwave frequencies. With $Ba_{+2}$ shortage, the sinterability and the unloaded Q( $Q_{u}$) were much improved, and the ordering in B site and the lattice distortion was greatly enhanced and the structure approached the completely ordered structure. $Q_{u}$ was strongly correlated with these factors such as ordering ratio, lattice distortion and sinterability, and had the maximum value of 7500 at x=0.01. The dielectric constant was near 30 and the temperature coefficient of the resonant frequency was 2 ppm/.deg. C at x=0.01.1.1.1.

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Aroma Characteristics of Acai Berry (아사이베리의 향기성분 특성 연구)

  • Lim, Seung-Hee;Nam, Heesop;Baek, Hyung-Hee
    • Korean Journal of Food Science and Technology
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    • v.48 no.2
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    • pp.122-127
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    • 2016
  • The objective of this study was to identify the volatile compounds and aroma-active compounds from acai berry (Euterpe oleracea). Volatiles were isolated by high vacuum distillation using solvent-assisted flavor evaporation (SAFE) and liquid-liquid continuous extraction (LLCE). To identify the characteristic aroma-active compounds of acai berry, gas chromatography-mass spectrometry-olfactometry was used. Aroma-active compounds were evaluated by aroma extract dilution analysis (AEDA). A total of 51 and 54 volatile compounds from acai berry were identified from SAFE and LLCE extracts, respectively. Alcohols were confirmed to be important volatile compounds in acai berry, as the major volatile compounds were 2-phenylethanol, (Z)-3-hexenol, and benzyl alcohol. ${\beta}-Damascenone$ (berry, rose), trans-linalool oxide (woody), (Z)-3-hexenol (grass), and 2-phenylethanol (rose, honey) were considered the aroma-active compounds in acai berry. The most intense aroma-active compound of acai berry was ${\beta}-damascenone$.

PCR Cloning of Genes Encoding the Mn-Peroxidase Isozyme Family from Trametes versicolor KN9522 Using Degenerate Primers (구름버섯균 KN9522에서 degenerate primer를 이용한 Mn-Peroxidase 동위효소 유전자들의 PCR 클로닝)

  • Jun, Sang-Cheol;Kim, Kyu-Joong
    • Korean Journal of Microbiology
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    • v.42 no.1
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    • pp.77-81
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    • 2006
  • Degenerate primers corresponding to the sequences of the N-terminal regions of Mn-peroxidase isozymes were used to isolate the genomic fragments encoding the isozymes of Mn-peroxidase, CVMP1, CVMP2, CVMP3 and CVMP5 from the white-rot fungus Trametes versicolor KN9522. Three isozymes except one gave the expected PCR products (cmp1, cmp2 and cmp5) of about 900 base pairs, respectively. DNA sequence data obtained from each PCR products were used to analyze the BLAST program search on the National Center for Biotechnology Information. cmp1, cmp2 and cmp5 were similar to MPG-I (GenBank accession number Z30668) and PGV-II (GenBank accession number, Z54279) gene T. versicolor PRL572. PCR products of cmp1 and cmp2 showed 77%, 95% base sequence similarities to MPG-I gene and cmp5 showed about 88% similarity to PGV-II gene from T. versicolor PRL572. From this experiment, we could isolate genomic DNA fragments with degenerate primers designed from the N-terminal amino acid sequences of Mn-peroxidase isozyme family.

Continuous rapid Production of Soy Sauce by Coimmobilized Mixed Culture system of Zygosaccharomyces rouxii and Candida versatilis using Air Bubble Column Reactor (Zygosaccharomyces rouxii와 Candida versatilis의 동시 고정화에 의한 Air Bubble Column Reactor에서 간장의 연속적 속성 생산)

  • 류병호
    • KSBB Journal
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    • v.18 no.6
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    • pp.455-460
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    • 2003
  • This study was designed to find out the rapid fermentation of soy sauce from koji hydrolyzates using air bubble column reactor packed with coimmobilized mixed culture system. Continuous ripid production was performed by coimmobilized Z. rouxiii BH-90 and C. versatilis BH-91. Coimmobilized cells of Zygosaccharomyces rouxii BH-90 and Candida versatilis BH-91 mixture cells in the column reactor produced 2.8% ethyl alcohol and 18mg/L 4-ethylguaiacol over 96 hours under the optimal conditions. Coimmobilized cells produced 2.30∼2.4% ethyl alcohol during 30 days, and decreased gradually from 40 days to 70 days. Also coimmobilized cells produced 4-ethylguaiacol at the constant rate of 16∼18mg/L and decreased gradually after 40 days. Final product of soy sauce contained 2.4% ethyl alcohol and 18mg/L 4-ethylguaiacol. However, amino acid compositions of soy sauce were consisted of predominantly glutamic acid, leucin, arginine, aspartic acid, Iysine and valine, which were more than 50% of total amino acid.

Research on Afterglow Brightness of Sr4-(x+y+z)Al14O25 : Eux, Dyy, Agz by Solid State Synthesis (고상법으로 합성한 Sr4-(x+y+z)Al14O25 : Eux, Dyy, Agz계 축광성 형광체 장잔광의 연구)

  • Kim, Seung-woo;Kim, Jung-sik
    • Korean Journal of Metals and Materials
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    • v.49 no.4
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    • pp.348-354
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    • 2011
  • Long-lasting brightness $Sr_{4}Al_{14}O_{25}$ : $Eu^{2+}$, $Dy^{3+}$, $Ag^{+}$ phosphor was synthesized by modified solid state reaction and its photoluminescence was investigated. $Sr(NO_3)_{2}$ and $Al(NO_3)_3{\cdot}9H_{2}O$ as starting materials, and $B_{2}O_{3}$ as a flux were mixed with $Eu_{2}O_{3}$ as an activator, $Dy_{2}O_{3}$ as a coactivator, and $AgNO_{3}$ as a charge compensator. The crystalline of target powder showed a single-phase $Sr_{4}Al_{14}O_{25}$ by the XRD characterization and the average particle size was about 20-30 ${\mu}m$ from the FE-SEM observation. $Ag^{+}$ ion doping effects (0-0.06 mol) on $Sr_{4}Al_{14}O_{25}:Eu^{2+},\;Dy^{3+},\;Ag^{+}$ phosphor were measured by photoluminescence spectrometer and luminescence meter. The of photoluminescence intensity of the $Sr_{3.64}Al_{14}O_{25}:Eu_{0.11},\;Dy_{0.22},\;Ag_{0.03}$ phosphor was higher than other compositions and afterglow brightness was 0.186 $cd/m^{2}$.

COLOR STABILITY OF NEW SILORANE-BASED COMPOSITE RESIN: AN IN VITRO SPECTROPHOTOMETRIC STUDY (Silorane-based 복합레진의 색안정성에 관한 연구)

  • Son, Yu-Jin;Hyun, Hong-Keun;Kim, Young-Jae;Kim, Jung-Wook;Lee, Sang-Hoon;Kim, Chong-Chul;Hahn, Se-Hyun;Jang, Ki-Taeg
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.1
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    • pp.73-81
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    • 2010
  • The objective of this study was to evaluate the color stability of new silorane-based composite resin compared with methacrylate-based composite resins after immersion in 3 staining solutions. One silorane-based composite(Filtek P90) and 3 methacrylate -based composites(Filtek Z250, Filtek Z350, Tetric Ceram) were evaluated. Twenty disk-shaped specimens($10{\times}2mm$) of each of 4 composite resins were prepared. The specimens were then divided into 4 groups of 5 specimens each and immersed in 3 staining solutions( coffee, red wine, curry solution) or distilled water(control) for 28-day test period. Color of the specimens was measured with a spectrophotometer(Color Eye 7000A) using CIE $L^*a^*b^*$ color space relative to CIE standard illuminant D65 at baseline, 1day, 3days, 7days, 14days, 21days and 28days after staining. The color differences( ${\Delta}{E^*}_{ab}$) were calculated. The results were obtained as follows ; 1. The mean color changes(${\Delta}{E^*}_{ab}$) of the composites were greatest in curry solution, then red wine, coffee and distilled water, in decreasing order. 2. The mean color changes(${\Delta}{E^*}_{ab}$) of the composites were greatest in Z350, Z250, Tetric Ceram and P90, in decreasing order.

An Analytical Study on the Stem-Growth by the Principal Component and Canonical Correlation Analyses (주성분(主成分) 및 정준상관분석(正準相關分析)에 의(依)한 수간성장(樹幹成長) 해석(解析)에 관(關)하여)

  • Lee, Kwang Nam
    • Journal of Korean Society of Forest Science
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    • v.70 no.1
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    • pp.7-16
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    • 1985
  • To grasp canonical correlations, their related backgrounds in various growth factors of stem, the characteristics of stem by synthetical dispersion analysis, principal component analysis and canonical correlation analysis as optimum method were applied to Larix leptolepis. The results are as follows; 1) There were high or low correlation among all factors (height ($x_1$), clear height ($x_2$), form height ($x_3$), breast height diameter (D. B. H.: $x_4$), mid diameter ($x_5$), crown diameter ($x_6$) and stem volume ($x_7$)) except normal form factor ($x_8$). Especially stem volume showed high correlation with the D.B.H., height, mid diameter (cf. table 1). 3) (1) Canonical correlation coefficients and canonical variate between stem volume and composite variate of various height growth factors ($x_1$, $x_2$ and $x_3$) are ${\gamma}_{u1,v1}=0.82980^{**}$, $\{u_1=1.00000x_7\\v_1=1.08323x_1-0.04299x_2-0.07080x_3$. (2) Those of stem volume and composite variate of various diameter growth factors ($x_4$, $x_5$ and $x_6$) are ${\gamma}_{u1,v1}=0.98198^{**}$, $\{{u_1=1.00000x_7\\v_1=0.86433x_4+0.11996x_5+0.02917x_6$. (3) And canonical correlation between stem volume and composite variate of six factors including various heights and diameters are ${\gamma}_{u1,v1}=0.98700^{**}$, $\{^u_1=1.00000x_7\\v1=0.12948x_1+0.00291x_2+0.03076x_3+0.76707x_4+0.09107x_5+0.02576x_6$. All the cases showed the high canonical correlation. Height in the case of (1), D.B.H. in that of (2), and the D.B.H, and height in that of (3) respectively make an absolute contribution to the canonical correlation. Synthetical characteristics of each qualitative growth are largely affected by each factor. Especially in the case of (3) the influence by the D.B.H. is the most significant in the above six factors (cf. table 2). 3) Canonical correlation coefficient and canonical variate between composite variate of various height growth factors and that of the various diameter factors are ${\gamma}_{u1,v1}=0.78556^{**}$, $\{u_1=1.20569x_1-0.04444x_2-0.21696x_3\\v_1=1.09571x_4-0.14076x_5+0.05285x_6$. As shown in the above facts, only height and D.B.H. affected considerably to the canonical correlation. Thus, it was revealed that the synthetical characteristics of height growth was determined by height and those of the growth in thickness by D.B.H., respectively (cf. table 2). 4) Synthetical characteristics (1st-3rd principal component) derived from eight growth factors of stem, on the basis of 85% accumulated proportion aimed, are as follows; Ist principal component ($z_1$): $Z_1=0.40192x_1+0.23693x_2+0.37047x_3+0.41745x_4+0.41629x_5+0.33454x_60.42798x_7+0.04923x_8$, 2nd principal component ($z_2$): $z_2=-0.09306x_1-0.34707x_2+0.08372x_3-0.03239x_4+0.11152x_5+0.00012x_6+0.02407x_7+0.92185x_8$, 3rd principal component ($z_3$): $Z_3=0.19832x_1+0.68210x_2+0.35824x_3-0.22522x_4-0.20876x_5-0.42373x_6-0.15055x_7+0.26562x_8$. The first principal component ($z_1$) as a "size factor" showed the high information absorption power with 63.26% (proportion), and its principal component score is determined by stem volume, D.B.H., mid diameter and height, which have considerably high factor loading. The second principal component ($z_2$) is the "shape factor" which indicates cubic similarity of the stem and its score is formed under the absolute influence of normal form factor. The third principal component ($z_3$) is the "shape factor" which shows the degree of thickness and length of stem. These three principal components have the satisfactory information absorption power with 88.36% of the accumulated percentage. variance (cf. table 3). 5) Thus the principal component and canonical correlation analyses could be applied to the field of forest measurement, judgement of site qualities, management diagnoses for the forest management and the forest products industries, and the other fields which require the assessment of synthetical characteristics.

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Effects of Maternal-Child Health Education Program for Nurses in Tigray, Ethiopia on Their Knowledge and Confidence (에티오피아 일개 지역 간호사를 위한 모자보건교육 프로그램이 간호사의 모자보건 지식과 수행자신감에 미치는 효과)

  • Bang, Kyung-Sook;Lee, Insook;Chae, Sun-Mi;Yu, Juyoun;Park, Jisun;Kim, Hyungkyung
    • Child Health Nursing Research
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    • v.20 no.4
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    • pp.275-282
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    • 2014
  • Purpose: The purpose of this study was to identify effects of a maternal-child health education program for nurses in Tigray, Ethiopia. Methods: One-group pre-posttest design was used. The maternal-child health (MCH) education program was given to nurses from 5 health centers in Tigray, Ethiopia. Knowledge and confidence levels were measured before and after each education session. Data were analyzed using paired t-test. Results: The topics of the 5 educational sessions were family planning, antenatal care, care during labor, immunization, and integrated management of neonate, and child illness. Knowledge scores (1st: Z=3.931, p=.001; 2nd: Z=6.189, p <.001; 3rd: Z=5.658, p <.001, 4th: Z=8.734, p <.001, 5th: Z=14.167, p <.001) and confidence levels (1st: Z=8.467, p <.001; 2nd: Z=4.183, p <.001; 3rd: Z=4.992, p <.001) improved significantly. Conclusion: The findings of this study imply that the MCH education program for nurses was effective in developing the maternal-child health capacity of the nurses in Tigray, Ethiopia.

An Analysis of Korean Dependency Relation by Homograph Disambiguation (동형이의어 분별에 의한 한국어 의존관계 분석)

  • Kim, Hong-Soon;Ock, Cheol-Young
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.6
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    • pp.219-230
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    • 2014
  • An analysis of dependency relation is a job that determines the governor and the dependent between words in sentence. The dependency relation of predicate is established by patterns and selectional restriction of subcategorization of the predicate. This paper proposes a method of analysis of Korean dependency relation using homograph predicate disambiguated in morphology analysis phase. The disambiguated homograph predicates has each different pattern. Especially reusing a stage transition training dictionary used during tagging POS and homograph, we propose a method of fixing the dependency relation of {noun+postposition, predicate}, and we analyze the accuracy and an effect of homograph for analysis of dependency relation. We used the Sejong Phrase Structured Corpus for experiment. We transformed the phrase structured corpus to dependency relation structure and tagged homograph. From the experiment, the accuracy of dependency relation by disambiguating homograph is 80.38%, the accuracy is increased by 0.42% compared with one of undisambiguated homograph. The Z-values in statistical hypothesis testing with significance level 1% is ${\mid}Z{\mid}=4.63{\geq}z_{0.01}=2.33$. So we can conclude that the homograph affects on analysis of dependency relation, and the stage transition training dictionary used in tagging POS and homograph affects 7.14% on the accuracy of dependency relation.