Effects of calcium doping on the superconducting properties of top-seeded melt growth processed Y_1.5Ba_2-xCa_xCu₃O_y superconductors

Park, S.D.,Kim, H.J.,Park, B.J.,Han, Y.H.,Jun, B.H.,Lee, J.S.,Kim, C.J. North-Holland 2011 Physica. C, Superconductivity Vol.471 No.21

The effect of calcium doping on the superconducting properties of top seeded melt growth (TSMG) processed Y<SUB>1.5</SUB>Ba<SUB>2-x</SUB>Ca<SUB>x</SUB>Cu<SUB>3</SUB>O<SUB>y</SUB> superconductors was studied in terms of calcium content (X<SUB>ca</SUB>). YBa<SUB>2-x</SUB>Ca<SUB>x</SUB>Cu<SUB>3</SUB>O<SUB>7-δ</SUB> (X<SUB>ca</SUB>=0, 0.005, 0.01, 0.02, 0.04, 0.1, 0.3) powders were synthesized by the powder calcination method. YBa<SUB>2-x</SUB>Ca<SUB>x</SUB>Cu<SUB>3</SUB>O<SUB>7-δ</SUB> powders were mixed with 0.25mole Y<SUB>2</SUB>O<SUB>3</SUB> powder and 1wt.% CeO<SUB>2</SUB> as Y<SUB>2</SUB>BaCuO<SUB>5</SUB> (Y211) refiner, and finally made into Y<SUB>1</SUB>.<SUB>5</SUB>Ba<SUB>2-x</SUB>Ca<SUB>x</SUB>Cu<SUB>3</SUB>O<SUB>y</SUB> (Y1.5)+1wt.% CeO<SUB>2</SUB> composition. The single Y123 growth on the top surface was observed up to X<SUB>ca</SUB>=0.1, while the multiple Y123 growth was observed at X<SUB>ca</SUB>≥0.1. The superconducting transition temperature (T<SUB>c</SUB>) and critical current density (J<SUB>c</SUB>) of TSMG processed Y1.5 samples were inversely proportional to X<SUB>ca</SUB>. The Y211 size increased with increasing X<SUB>ca</SUB> due to the enhancement of Y211 coarsening by calcium doping. No Y211 refining effect by CeO<SUB>2</SUB> was observed in the calcium doped samples. The T<SUB>c</SUB> and J<SUB>c</SUB> decrease by calcium doping are likely to be due to the calcium incorporation with the Y123 lattice and formation of coarse Y211 particles.

Analysis of 22 Y chromosomal STR haplotypes and Y haplogroup distribution in Pathans of Pakistan

Lee, E.Y.,Shin, K.J.,Rakha, A.,Sim, J.E.,Park, M.J.,Kim, N.Y.,Yang, W.I.,Lee, H.Y. Elsevier Science 2014 FORENSIC SCIENCE INTERNATIONAL GENETICS Vol.11 No.-

We analyzed haplotypes for 22 Y chromosomal STRs (Y-STRs), including 17 Yfiler loci (DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DY438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y-GATA-H4) and five additional STRs (DYS388, DYS446, DYS447, DYS449 and DYS464), and Y chromosomal haplogroup distribution in 270 unrelated individuals from the Pathans residing in the Federally Administered Tribal Areas and the North-West Frontier Province of Pakistan using in-house multiplex PCR systems. Each Y-STR showed diversities ranging from 0.2506 to 0.8538, and the discriminatory capacity (DC) was 73.7% with 199 observed haplotypes using 17 Yfiler loci. By the addition of 5 Y-STRs to the Yfiler system, the DC was increased to 85.2% while showing 230 observed haplotypes. Among the additional 5 Y-STRs, DYS446, DYS447 and DYS449 were major contributors to enhancing discrimination. In the analysis of molecular variance, the Pathans of this study showed significant differences from other Pathan populations as well as neighboring population sets. In Y-SNP analysis, a total of 12 Y chromosomal haplogroups were observed and the most frequent haplogroup was R1a1a with 49.3% frequency. To obtain insights on the origin of Pathans, the network analysis was performed for the haplogroups G and Q observed from the Pathans and the Jewish population groups including Ashkenazim and Sephardim, but little support for a Jewish origin could be found. In the present study, we report Y-STR population data in Pathans of Pakistan, and we emphasize the need for adding additional markers to the commonly used 17 Yfiler loci to achieve more improved discriminatory capacity in a population with low genetic diversity.

Effects of $BaCO_3$ purity on the superconducting properties of top seeded melt growth processed $Y_{1+x}Ba_2Cu_3O_y$ superconductors

Choi, J.S.,Park, S.D.,Jun, B.H.,Han, Y.H.,Sung, T.H.,Choo, K.N.,Kim, C.J. The Korean Society of Superconductivity and Cryoge 2009 한국초전도저온공학회논문지 Vol.11 No.2

Effects of $BaCO_3$ purity on the superconducting properties of top seeded melt growth (TSMG) processed $Y_{1+x}Ba_2Cu_3O_{7-y}$ (Y1+x, x=0.1 and 0.2) superconductors were investigated. $YBa_2Cu_3O_{7-y}$ (Y123) powder prepared using $BaCO_3$ with 99.75% purity and commercially available Y123 powder of 99.9% were used for the fabrication of single Y123 grain superconductors. $T_c$ values of the Y1+x samples prepared using low purity Y123 powder were slightly lower than those of the samples prepared using a high purity powder. In addition to the lower $T_c$, an anomalous peak effect in the intermediate magnetic fields was observed in Y1+x samples prepared using the low purity $BaCO_3$ powder. The slight decrease in $T_c$ and the anomalous peak effect are ascribed to the possible incorporation of a Y123 phase with impurity elements such as strontium and calcium included in the $BaCO_3$powder of 99.7%. The result suggests that the low purity $BaCO_3$ powder of a low price can be used as a raw power for the fabrication of single grain YBCO bulk superconductors.

Effects of Y₂O₃ additions on the oxygen diffusion in top-seeded melt growth processed YBa₂Cu₃O_7-y superconductors

Jun, B.H.,Jung, S.A.,Park, S.D.,Park, B.J.,Han, Y.H.,Kim, C.J. North-Holland 2011 Physica. C, Superconductivity Vol.471 No.21

To understand the effect of Y<SUB>2</SUB>BaCuO<SUB>5</SUB> (Y211)/YBa<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7-y</SUB> (Y123) interfaces on the oxygen diffusion in single grain YBa<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7-y</SUB> superconductors, single grain Y123 superconductors with 0.05 and 0.3moles of Y<SUB>2</SUB>O<SUB>3</SUB> additions were fabricated by a top-seeded melt growth (TSMG) process. Y123 compacts with Y<SUB>2</SUB>O<SUB>3</SUB> additions were subjected to melt growth heating cycles with a cooling rate of 1<SUP>o</SUP>C/h through a peritectic temperature (1015<SUP>o</SUP>C) and then annealed at 450<SUP>o</SUP>C for 200h in flowing oxygen. The superconducting temperature (T<SUB>c</SUB>) and critical current density (J<SUB>c</SUB>) were estimated for the three different regions (top surface (s), intermediate (i) and center (c)) of samples. The amount of Y211/Y123 interface area in single grain Y123 superconductors was successfully controlled by Y<SUB>2</SUB>O<SUB>3</SUB> additions. The T<SUB>c</SUB> values of s regions were higher than those of i and c regions, which indicates the presence of more oxygen at the sample surfaces. In addition, the T<SUB>c</SUB> values of i and c regions of the Y123 sample with 0.3mole Y<SUB>2</SUB>O<SUB>3</SUB> addition were higher than those of the same regions of the Y123 sample with 0.05mole Y<SUB>2</SUB>O<SUB>3</SUB> addition due to the promoted oxygen diffusion through Y211/Y123 interfaces and other related defects. In spite of the promoted oxygen diffusion by Y<SUB>2</SUB>O<SUB>3</SUB> addition, the large T<SUB>c</SUB> difference among the regions still existed, which suggests sluggish oxygen diffusion into single Y123 grains.

음이온 치환을 이용한 Li_1-xFeO_2-yF_y-Li_xMnO₂ (Mn/(Mn + Fe) = 0.8, 0≤y≤0.15) 양극 활물질의 합성 및 전기화학적 특성

허정배,박금재,이윤성,Heo, J.B.,Park, G.J.,Lee, Y.S. 한국전기화학회 2007 한국전기화학회지 Vol.10 No.4

산소자리에 치환된 불소가 $Li_{1-x}FeO_2Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8) 양극 활물질에 미치는 영향을 고찰하기 위해 다양한 양의 불소를 치환시킨 $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.05{\le}y{\le}0.15$) 양극 활물질을 고상법을 이용하여 합성하였다. 불소 미치환 시료 및 치환양이 0.05와 0.1의 시료의 경우, $1-1.5\;{\mu}m$ 크기의 막대 형상 분말 형태에 50-100 nm정도의 작은 구형 입자들이 주위에 분포되어 있는 형태이었다. 반면, 불소 치환양이 0.15인 시료의 경우, 그 모양이 구형으로 변화되어지며 입자가 급격하게 성장하였다. 합성된 시료를 이용하여 제작된 셀들의 충 방전 수행 결과, $Li/Li_{1-x}FeO_{1.9}F_{0.1}-Li_xMnO_2$ 셀이 163 mAh/g의 가장 높은 초기용량을 보였으며 50 싸이클 후에도 95%의 높은 가역 특성을 보였다. 특히, 활물질내의 불소 치환양이 증가할수록 초기 방전용량도 같이 증가하였으나, 불소이온의 치환양이 일정량을 (y>0.1) 넘는 경우에는 산소 자리에 불소이온이 완전하게 치환되지 못하고 불순물로 존재함으로써 전지의 가역특성을 현저하게 저하시키는 요인으로 작용함을 확인하였다. In order to investigate the effect of fluorine ion in the $Li_{1-x}FeO_2Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8) cathode material, it was synthesized $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.05{\le}y{\le}0.15$) cathode materials at $350^{\circ}C$ for 10hrs using solid-state method. $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.0{\le}y{\le}0.1$ was composed many large needle-like particles of about $1-1.5\;{\mu}m$ and small particles of about 50-100 nm, which were distributed among the larger particles. However, $Li_{1-x}FeO_{1.85}F_{0.15}-Li_xMnO_2$ material showed slightly different particle morphology. The particles of $Li_{1-x}FeO_{1.85}F_{0.15}-Li_xMnO_2$ were suddenly increased and started to be a spherical type of particle shape. $Li/Li_{1-x}FeO_{1.9}F_{0.1}-Li_xMnO_2$ cell showed a high initial discharge capacity of 163 mAh/g and a high cycle retention rate of 95% after 50 cycles. The initial discharge capacity of $Li/Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ ($0.05{\le}y{\le}0.15$) cells increased according to the increase of F content. However, the cycleability of this cell was very rapidly decreased when the substituted fluorine content is over 0.1. We suggested that too large amount of F ion fail to substitute into the $Li_{1-x}FeO_2-Li_xMnO_2$ structure, which resulted in the severe decline of battery performance.

Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation

Kim, S.-H.,Lee, S.-O.,Park, I.-A.,Park, S.J.,Choi, S.-H.,Kim, Y.S.,Woo, J.H.,Park, S.-K.,Park, J.S.,Kim, S.C.,Han, D.J. Blackwell Publishing Inc 2010 Transplant infectious disease Vol.12 No.2

<P>S.-H. Kim, S.-O. Lee, I.-A. Park, S.J. Park, S.-H. Choi, Y.S. Kim, J.H. Woo, S.-K. Park, J.S. Park, S.C. Kim, D.J. Han. Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation.Transpl Infect Dis 2010: <B>12:</B> 113–119. All rights reserved</P><P>Background</P><P>The presence of latent tuberculosis (TB) infection (LTBI) should be evaluated before kidney transplantation. Although a new T cell-based assay for diagnosing LTBI gave promising results, this assay has not yet been compared with the tuberculin skin test (TST) for diagnosing LTBI in renal transplant candidates before transplantation.</P><P>Patients and methods</P><P>All adult patients admitted to a single institute for renal transplantation over a 1-year period were prospectively enrolled. A clinically predictive risk of LTBI was defined as: (i) recent close contact with a person with pulmonary TB; (ii) abnormal chest radiography; (iii) a history of untreated or inadequately treated TB; or (iv) a new infection (i.e., a recent conversion of TST).</P><P>Results</P><P>Of 209 renal recipients, 47 (22%) had a positive TST≥5 mm, 21 (10%) had a positive TST≥10 mm, 65 (30%) had a positive T-SPOT.<I>TB</I> test, and 25 (12%) had an indeterminate T-SPOT.<I>TB</I> test. The induration size of TST was significantly associated with a high positivity rate on T-SPOT.<I>TB</I> (<I>P</I><0.001). Agreement between T-SPOT.<I>TB</I> test and TST≥10 mm was fair (<I>k</I>=0.24, 95% confidence interval 0.11–0.36). However, neither univariate nor multivariate analysis showed any association between the clinical risk for LTBI and positivity on T-SPOT.<I>TB</I> or TST.</P><P>Conclusion</P><P>T-SPOT.<I>TB</I> test was more frequently positive than TST in renal transplant candidates. However, further longitudinal studies are awaited to determine whether the ability of T-SPOT.<I>TB</I> assay to detect LTBI in renal transplant recipients can better predict the development of TB than can TST after transplantation.</P>

공정육묘 온실의 표준모델 및 자동화 시스템 개발과 활용기술연구 5 : 제5장 공정육묘사업의 경영분석과 경영체계 수립 Chapter5 Management Analysis of Plug Production Bussiness and Establishment of Management System

박중춘,민영봉,정병룡,설인준,이영만,윤용철,강호종,김태규,김광용,장사문,정한택,오태한,김평태,김진일,손영걸,박봉식,김시론,이형정,오상석,김명승,조정호,하종규,임동희,이은주,변정희,이정한,최우진,강환규 경상대학교 시설원예연구소 1997 施設園藝硏究 Vol.4 No.-

발화합성용액의 pH가 Y₁Ba₂Cu₃O_7-x 초전도상 생성 속도에 미치는 영향

박정식,김영순,양석우,김춘영,신형식,Park, J.S.,Kim, Y.S.,Yang, S.W.,Kim, C.Y.,Shin, H.S. 한국공업화학회 1998 공업화학 Vol.9 No.2

$Y_2O_3$(99.9%)와 $BaCO_3$(99.9%) 및 CuO(99.9%)를 사용하여 $Y_1Ba_2Cu_3O_{7-x}$(123) 분말을 발화합성법에 의해 제조하였다. 발화전 용액을 여러 가지 pH로 변화시켜 제조하였으며, 이 분말을 성형하여 열처리 온도와 시간 변화에 따른 상형성과 반응특성을 조사하였다. 시료의 조성과 조직의 특성은 ICP와 SEM을 이용하여 측정하였고, Y-Ba-Cu-O계의 상형성과 전화율을 결정하기 위해 X선 회절분석을 하였다. 발화합성법을 이용하여 pH 7(${\pm}0.3$)에서 제조된 123 분말이 순도와 균일성 및 반응특성에서 가장 좋은 결과를 보였다. pH 7(${\pm}0.3$)에서 제조된 분말을 이용한 123 상생성에 따른 활성화에너지(${\Delta}E_a$)는 191kJ/mol으로서 고상반응법의 230kJ/mol에 약 13% 정도 더 낮았다. The $Y_1Ba_2Cu_3O_{7-x}$(123) superconductor powders were prepared by pyrophoric synthesis method(PSM) using $Y_2O_3$(99.9%), $BaCO_3$(99.9%), and CuO(99.9%) powders. The phase formation and reaction kinetics of 123 superconductor manufactured with powders prepared in various pHs of pyrophoric synthetic solution have been studied through the experiments at various heat treatment temperatures and times. Inductively coupled plasma(ICP) spectroscopy and scanning electron microscopy(SEM) measurements were performed to examine the composition and morphology of the sample. X-ray diffraction(XRD) analysis was done to determine phase formation and conversion ratio of Y-Ba-Cu-O systems. The 123 powder prepared at pH 7(${\pm}0.3$) yields the best result in terms of purity, homogeneity, and reactivity. The activation energies(${\Delta}E_a$) of 123 phase formation were found to be 191 kJ/mol and 230kJ/mol in solid state reaction method and pyrophoric synthesis method, respectively.

간호대학생의 에니어그램 성격유형에 따른스트레스 대처방식

김희주,박가영,박지영,송예빈,심지현,이수연,이지영,장주희,정영민 이화여자대학교 간호과학대학 2011 이화간호학회지 Vol.- No.45

The purpose of this study is to analyze the relationship between stress coping behaviors and Enneagram personality types. The subject of the study is 342 college students who are attending 4-year nursing colleges in Seoul, Korea, and 198 students among them are qualified for the study. Typified statistical tools SPSS, chi-square, and ANOVA are used as analyzing methods in the study. The research results are as follows: 1. In nursing students, freshman class is the highest population in the study with 63 students(31.82 %), and the highest percentage of population does not have a religion(89 students, 44.95 %). 120 students (60.61 %) answered that their interpersonal relationships are good, and 105 students(53.03 %) are satisfied with the nursing major. 2. In Enneagram personality type, 9 type is the highest(42.42 %). 3. Problem focused coping type is the highest in stress coping behaviors(28.12(±20.16) points). 4. Problem focused coping behavior and social support coping behavior show significance. 5. Social support coping behavior shows significance, and 3 type scored the highest(17.67(±2.66) points). Further studies are suggested based on above results: First, in order to achieve more accurate results, the research of Enneagram and stress coping behavior with representative for sample Korean nursing students is necessary. Second, Development and verification the effect of stress coping program based on Enneagram personality types among nursing students are necessary.

20대 여성의 신발종류에 따른 족저압 영역별 비교 연구

김용재,지진구,김정태,홍준희,이중숙,이훈식,박승범 한국운동역학회 2004 한국운동역학회지 Vol.14 No.3

Y. J. KIM, J. G. JI, J. T. KIM, J. H. HONG, J. S. LEE, H. S. LEE, S. B. PARK. A comparison study for mask plantar pressure measures to the difference of shoes in 20 female. Korean Journal of Sport Biomechanics, Vol. 14, No. 3, pp. 83-98, 2004. The purpose of this study was to investigate the test-retest of plantar pressures using the F-Scan system over speeds and plantar regions. 6 healthy female subjects in 20's were recruited for the study. Plantar pressure measurements during locomotor activities can provide information concerning foot function, particularly if the timing and magnitude of the loading profile can be related to the location of specific foot structures such as the metatarsal heads. The Tekscan F-Scan system consists of a flexible, 0.18mm thick sole-shape having 1260 pressure sensors, the sensor insole was trimmed to fit the subjects' right. left shoes - sneakers shoes & dress shoes. It was calibrated by the known weight of the test subject standing on one foot. The Tekscan measurements show the insole pressure distribution as a function of the time. This finding has important implications for the development of plantar pressure test protocols where the function of the forefoot is important. According to the result of analysis it is as follows : 1) Center of force trajectory in women's dress shoes display direct movement, compare with center of force trajectory in Sneaker shoes displays a little bit curved slow pronation movement. Sneaker shoes in forefoot part display very quick supination movement, therefore, this shoes effects negative effectiveness for ankle's stability. Considering center of force trajectory analyzing, the more center of force close straight line, the more movement can be quick movement for locomotion. For foot pressure distribution, center of force trajectory in locomotion is better to curved trajectory with pronation movement. So sneaker shoes style is good shoes considering center of pressure distribution trajectory compare with women's dress shoes. 2) Women's dress shoes increased peak pressure in medial, this is effected by high hill's height. The more increased women's dress shoes's height, the more women's peak pressure will increase, pronation can increase compare with before. Supination movement increase, this focused pressure in lateral, also, supination increased more. If the supination movement increased, foot pressure focused in lateral, therefore, it is appeared force distribution in gait direction. This is bad movement in foot's stability. 3) Women's dress shoes in landing phase displayed a long time, this is when women's dress shoes wear, gait movement is unbalance, so, landing phase displayed a long time. For compensation in gait, swing phase quick movement. 4) Women's dress shoes displayed peak pressure distribution in lateral of rearfoot part, Sneakers shoes displayed peak pressure distribution in medial of forefoot part. Its results has good impact absorption compare with women's dress shoes. In forefoot part, sneakers shoes has good propulsive force compare with women's dress shoes.