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.

한국잔디 수집계통들 중에서 우수계통들의 생육특성 비교

임용우(Y. W. Rim),김기용(K. Y. Kim),김맹중(M. J. Kim),성병렬(B. R. Sung),임영철(Y. C. Lim),정의수(E. S. Chung),신홍균(H. K. Shin),김용선(Y. S. Kim) 한국잡초학회·한국잔디학회 2003 Weed & Turfgrass Science Vol.17 No.2,3

2001년 수집된 한국잔디 133계통들 중에서 우수한 계통들을 선발하기위하여 밀도(품질),<br/> 피복성, 녹색기간, 내병성, 출수유무(종자수) 등의 주요특성과 그 외 생육특성들이 조사되었다. 생육특성이 우수한 6계통이 선발되었으며 그 결과를 요약하면 다음과 같다.<br/> 수집된 133계통들 중에서 가장 녹색기간이긴 계통은 J01067으로 11월초까지 녹색도를 유지하였다. J01106 및 J01129 계통들은 엽폭이 각각 1.5mm 및 2mm 정도로 매우 좁으며, 밀도가 높고, 피복성도 좋은 것으로 나타났으며, 내병성도 강하였다. J01122 계통은 들잔디 계통들 중에서 유일하게 내병성이 강한 계통으로 선발되었다. J01128 계통은 엽폭이 3.2mm로 중엽에 속하였으며, 대비품종인 Sunburst 와 비슷하였다. 이 계통의 경우도J01106, J01129 계통들과 마찬가지로 밀도가 높고 내병성이 강한 것으로 나타났다.<br/> 수집된 133계통들의 형태적 분류를 위하여 5가지의 생육특성을 사용하여 크게 세가지 군집<br/> 으로 분류하였으며, 그 중에서 대비품종으로 사용된 6품종들과 선발된 우수 6계통의 분류는<br/> 다음과 같다. 제 1군집에 속하는 품종 및 계통은 Belare, Meyer, 안양중지(Anyang-jungji), J01067, J01112 등이 포함되었으며, 제 2군집으로는 S-94, J01105가 포함되었고, 제 3군집에는 Sunburst, 건희(Konhee), J01106, J01128, J01129 등이 포함되었다. Growth characteristics such as density(quality), covering speed, green period, disease resistance, heading existence(number of seeds) and other characteristics were examined for selection of superior lines among the 133 zoysiagrass lines collected in 2001. Six superior lines were selected and the results were summarized as follows.<br/> Superior line, J01067 was longest for green period among the 133 zoysiagrasses and stayed green until the beginning of November. Leaf width of J01106 and J01129 lines was very narrow as 1.5㎜ and 2㎜, respectively and superior for density(quality), covering speed and disease resistance. J01122 line was selected for strongest disease resistance among the lines of Zoysia japonica. Leaf width of J01128 was 3.2㎜ showing midium type and similar to standard cultivar, Sunburst. This line also showed higher density and strong disease resistance like J01106 and J01129.<br/> Five growth characteristics for morphological classification of 133 zoysiagrass lines<br/> was used and divided into 3 cluster groups. Of 133 lines, 6 standard cultivars and 6 superior lines were classified as follows. First cluster group contained Belare, Meyer, Anyang-jungji, J01067, J01122, and second group contained S-94 and J01105, and third group contained Sunburst, Konhee, J01106, J01128 and J01129.<br/> <br/>

Confirmation of Y haplogroup tree topologies with newly suggested Y-SNPs for the C2, O2b and O3a subhaplogroups

Kwon, S.Y.,Lee, H.Y.,Lee, E.Y.,Yang, W.I.,Shin, K.J. Elsevier Science 2015 FORENSIC SCIENCE INTERNATIONAL GENETICS Vol.19 No.-

Y chromosome single nucleotide polymorphisms (Y-SNPs) are useful markers for reconstructing male lineages through hierarchically arranged allelic sets known as haplogroups, and are thereby widely used in the fields such as human evolution, anthropology and forensic genetics. The Y haplogroup tree was recently revised with newly suggested Y-SNP markers for designation of several subgroups of haplogroups C2, O2b and O3a, which are predominant in Koreans. Therefore, herein we analyzed these newly suggested Y-SNPs in 545 unrelated Korean males who belong to the haplogroups C2, O2b or O3a, and investigated the reconstructed topology of the Y haplogroup tree. We were able to confirm that markers L1373, Z1338/JST002613-27, Z1300, CTS2657, Z8440 and F845 define the C2 subhaplogroups, C2b, C2e, C2e1, C2e1a, C2e1b and C2e2, respectively, and that markers F3356, L682, F11, F238/F449 and F444 define the O subhaplogroups O2b1, O2b1b, O3a1c1, O3a1c2 and O3a2c1c, respectively. Among six C2 subhaplogroups (C2b, C2e, C2e1*, C2e1a, C2e1b and C2e2), the C2e haplogroup and its subhaplogroups were found to be predominant, and among the four O2b subhaplogroups (O2b*, O2b1*, O2b1a and O2b1b), O2b1b was most frequently observed. Among the O3a subhaplogroups, O3a2c1 was predominant and it was further divided into the subhaplogroups O3a2c1a and O3a2c1c with a newly suggested marker. However, the JST002613-27 marker, which had been known to define the haplogroup C2f, was found to be an ancestral marker of the C2e haplogroup, as is the Z1338 marker. Also, the M312 marker for the O2b1 haplogroup designation was replaced by F3356, because all of the O2b1 haplotypes showed a nucleotide change at F3356, but not at M312. In addition, the F238 marker was always observed to be phylogenetically equivalent to F449, while both of the markers were assigned to the O3a1c2 haplogroup. The confirmed phylogenetic tree of this study with the newly suggested Y-SNPs could be valuable for anthropological and forensic investigations of East Asians including Koreans.

Investigation into the sequence structure of 23 Y chromosomal STR loci using massively parallel sequencing

Kwon, S.Y.,Lee, H.Y.,Kim, E.H.,Lee, E.Y.,Shin, K.J. Elsevier Science 2016 FORENSIC SCIENCE INTERNATIONAL GENETICS Vol.25 No.-

Next-generation sequencing (NGS) can produce massively parallel sequencing (MPS) data for many targeted regions with a high depth of coverage, suggesting its successful application to the amplicons of forensic genetic markers. In the present study, we evaluated the practical utility of MPS in Y-chromosome short tandem repeat (Y-STR) analysis using a multiplex polymerase chain reaction (PCR) system. The multiplex PCR system simultaneously amplified 24 Y-chromosomal markers, including the PowerPlex<SUP>®</SUP> Y23 loci (DYS19, DYS385ab, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS481, DYS533, DYS549, DYS570, DYS576, DYS635, DYS643, and YGATAH4) and the M175 marker with the small-sized amplicons ranging from 85 to 253bp. The barcoded libraries for the amplicons of the 24 Y-chromosomal markers were produced using a simplified PCR-based library preparation method and successfully sequenced using MPS on a MiSeq<SUP>®</SUP> System with samples from 250 unrelated Korean males. The genotyping concordance between MPS and the capillary electrophoresis (CE) method, as well as the sequence structure of the 23 Y-STRs, were investigated. Three samples exhibited discordance between the MPS and CE results at DYS385, DYS439, and DYS576. There were 12 Y-STR loci that showed sequence variations in the alleles by a fragment size determination, and the most varied alleles occurred in DYS389II with a different sequence structure in the repeat region. The largest increase in gene diversity between the CE and MPS results was in DYS437 at +34.41%. Single nucleotide polymorphisms (SNPs), insertions, and deletions (indels) were observed in the flanking regions of DYS481, DYS576, and DYS385, respectively. Stutter and noise ratios of the 23 Y-STRs using the developed MPS system were also investigated. Based on these results, the MPS analysis system used in this study could facilitate the investigation into the sequences of the 23 Y-STRs in forensic genetics laboratories.

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.

Haplotype and mutation analysis for newly suggested Y-STRs in Korean father-son pairs

Oh, Y.N.,Lee, H.Y.,Lee, E.Y.,Kim, E.H.,Yang, W.I.,Shin, K.J. Elsevier Science 2015 FORENSIC SCIENCE INTERNATIONAL GENETICS Vol.15 No.-

In this study, 363 Korean father-son haplotype transfers in 351 families were analyzed using an in-house multiplex PCR system for 14 Y-STRs (DYS385a/b, DYF387S1, DYS391, DYS449, DYS460, DYS481, DYS518, DYS533, DYS549, DYS570, DYS576, DYS627 and DYS643), that included 11 loci newly added to the PowerPlex Y23 system or the Yfiler Plus system. The Y-STRs showed gene diversity values ranging from 0.2499 to 0.9612; the multicopy Y-STR loci DYS385 and DYF387S1 had high gene diversity of 0.9612 and 0.9457, respectively. In addition, DYF387S1, which has two copies, showed three alleles in seven individuals, and micro-variant alleles were observed in 14 individuals at four loci (DYS448, DYS518, DYS570 and DYS627). Among 351 haplotypes for the 11 newly added Y-STRs, 350 different haplotypes were observed, with an overall haplotype diversity of 0.9999 and discrimination capacity of 99.72%. In 363 haplotype transfers from 351 pedigrees, 29 single-step mutations were observed at 11 Y-STRs. Locus-specific mutation rate estimates varied from 0.0 to 1.93x10<SUP>-2</SUP>, with an average estimated mutation rate of 6.66x10<SUP>-3</SUP>. Two father-son pairs had mutations at two different loci in 11 Y-STRs. The number of pairs with mutations at multiple loci increased to five when the mutation event was investigated for haplotype transfer at 28 Y-STRs including 17 Yfiler loci and 11 Y-STRs examined in this study: four father-son pairs had mutations at two loci, and one pair had mutations at three loci. Overall, mutations were frequently observed at DYS449, DYS576 and DYS627 loci, which are known to be rapidly mutating Y-STRs. Mutation rate estimates at most loci were not significantly different from rates in other populations, but estimates for DYF387S1, DYS518 and DYS570 were considerably lower in the Korean population than in other populations.

Particle distribution in melt-processed Y_1.5 Ba₂Cu₃O_x superconductors with BaCeO₃ addition

Youn, J.S.,No, K.,Kim, Y.H.,Mahmood, A.,Jun, B.H.,Han, Y.H.,Sung, T.H.,Kim, C.J. North-Holland 2009 Physica. C, Superconductivity Vol.469 No.15

To understand the effect of BaCeO<SUB>3</SUB> on a Y<SUB>2</SUB>BaCuO<SUB>5</SUB> (Y211) distribution, Y<SUB>1.5</SUB>Ba<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>x</SUB> (Y1.5) superconductors with/without 1wt.% BaCeO<SUB>3</SUB> additions were prepared by a top-seeded melt-textured growth (TSMG) process. Two different BaCeO<SUB>3</SUB> powders (as-synthesized (coarse powder) and an attrition-milled (fine powder)) were used and the size effect was compared with that obtained from a Y1.5 sample with no addition. A refinement of the Y211 particles was achieved for both the as-synthesized and attrition-milled BaCeO<SUB>3</SUB> additions. The distribution of the Y211 particles was most uniform in the Y1.5 sample prepared with the attrition-milled BaCeO<SUB>3</SUB> powder due to the reduced size of the Y211-free regions by the fine size BaCeO<SUB>3</SUB> addition. The highest J<SUB>c</SUB> was achieved in the Y1.5 sample prepared with the attrition-milled BaCeO<SUB>3</SUB> powder. The J<SUB>c</SUB> result agreed well with the microstructure variations by the addition of BaCeO<SUB>3</SUB> powders.

The effects of Sm and Y addition on the properties of YBCO thin film prepared by a DCA-MOD method

Kim, B.J.,Yu, J.H.,Lee, J.B.,Yoo, Y.S.,Kim, J.G.,Lee, H.G.,Hong, G.W. North-Holland 2009 Physica. C, Superconductivity Vol.469 No.15

Off-stoichiometric (Y<SUB>1</SUB>RE<SUB>x</SUB>)Ba<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7-δ</SUB>; (x=0-0.4, RE=Y or Sm) films have been prepared on LaAlO<SUB>3</SUB> (100) single-crystal substrates by a metal-organic deposition using dichloroacetic acid as chelating solution. Coating solutions with excess Sm or Y were prepared by dissolving Y, Sm, Ba and Cu acetates in dichloroacetic acid and distilled water followed by refluxing, drying to obtain blue gel. The final precursor solution for dip coating was prepared by diluting blue gel in 2-methoxyethanol. Coated films were calcined at low temperature up to 500<SUP>o</SUP>C in flowing humid oxygen atmosphere. Conversion heat treatment was performed at 800<SUP>o</SUP>C for 2h in flowing Ar gas containing 1000ppm oxygen with a humidity of 9.45%. The viscosities of the precursor solution were increased as the content of added Sm or excess Y increased. The transport critical current density (J<SUB>c</SUB>) of (Y<SUB>1</SUB>RE<SUB>x</SUB>)Ba<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7-δ</SUB>; film was enhanced with the addition of excess Sm and Y up to 20% and then decreased with further addition. Scanning electron microscope (SEM) observation showed that surface roughness was increased with the addition of excess Y.

식물성 세포벽에 함유된 Ca과 P의 Rooster에 있어서 소화율에 관한 연구

김종쾌,김영규,김대진 東亞大學校 1992 東亞論叢 Vol.29 No.1

본 연구는 綠葉중에서 ladino clover 잎, alfalfa 잎, 칡잎, 아카시아잎, 싸리잎 등을 5월과 6월의 生育시기를 두 시기로 하여 동물 체내에서 Ca과 P 그리고 NDF에 결합된 Ca과 P의 이용성을 조사하였다. 실험에 사용된 동물은 10개월된 재래 숫탉(rooster)으로서 이들 綠葉은 체중 kg당 약 1% 강제 급여(forced feeding) 한 후 36시간 동안의 배설물을 채취하였으며, 이와 동시에 대사성 糞과 내인성 뇨로 분비되는 Ca과 P을 보정하기 위하여 36시간 절식시켜서 배설물을 채취하였다. 생체내 Ca과 P의 이용성 실험은 세번 반복을 하였으며, 대사성 분과 내인성 뇨 실험도 다섯번 반복을 실시하였는데 그 결과를 요약하면 다음과 같다. 1. NDF 含量에 있어서 綠葉(ladino clover잎, alfalfa 잎, 칡잎, 아카시아잎, 싸리잎)은 5월 예취가 30.42%-37.28% 범위였으며, 6월 예취는 45.43-59.36% 점위로 生育이 進行됨에 따라 增加하였다. (p<0.05). 2. 眞正 DM 消化率(TDMD)에 있어서 綠葉은 5월 예취가 24.75-47.24%의 범위였으며, 6월 예취는 23.31-42.20% 범위로 生育이 進行됨에 따라 減少하였다(p<0.01). 3. 眞正 이용 Ca(TACa)에 있어서 綠葉은 5월 예취가 7.94-56.65%의 범위였으며, 6월 예취는 4.02-51.09% 범위로 生育이 進行됨에 따라 alfalfa 잎은 增加하였으나, ladino clover 잎은 減少하였고(p<0.05), 칡잎, 아카시아잎은 뚜렷한 변화가 없었다. 4. 眞正 이용 P(TAP)에 있어서 綠葉은 5월 예취가 8.52-4.89%의 범위였으며, 6월 예취는 24.86-42.6%로 生育이 進行됨에 따라 增加하였으나 ladino clover 잎에서는 減少하였다(p<0.05). 5. NDF에 결합된 Ca의 이용율에 있어서 綠葉은 5월 예취가 4.04-15.80%의 범위였으며, 6월 예취는 3.23-8.11%로 生育이 進行됨에 따라 減少하였으나 (p<0.05), ladino clover 잎, 싸리잎은 뜨렷한 변화가 없었다. 6. NDF에 결합된 P의 이용율에 있어서 綠葉은 5월 예취가 3.97-17.01% 범위였으며, 6월 예취는 4.06-14.93%로 生育이 進行됨에 따라 ladino clover잎, 칡잎, 아카시아잎은 減少하였으나(p<0.05), la-dinl clover 잎과 싸리잎은 뚜렷한 변화가 없었다. 7. 綠葉에 있어서 TDMD(Y) 含量과 NDF 含量(X) 사이에는 Y=53.5-0.42X의 回歸式과 r=-0.50의 相關關係를 보였다(p<0.01). 8. Ladinl clover 잎의 P-D(Y)와 P 含量(X) 사이에는 Y=84.5-85.1X의 回歸式과 r=-0.91의 相關關係를 보였다(p<0.01). 9. Alfalfa 잎의 Ca-D(Y)와 Ca含量(x) 사이에는 Y=18.9+13.0X의 回歸式과 r=0.99의 相關關係를 보였다(p<0.01). 10. 칡잎의 P-D(Y)와 P含量(X) 사이에는 Y=139-368X의 回歸式과 r=-0.95의 相關關係를 보였다(p<0.01). 11. 아카시아잎의 P-D(Y)와 P含量(X) 사이에는 Y=87.8-229X의 回歸式과 r=-0.98의 相關關係를 보였다(p<0.01). 12. 싸리잎의 Ca-D含量(Y)과 Ca含量(X) 사이에는 Y=17.9-12.8X의 回歸式과 r=-0.83의 相關關係를 보였다(p<0.01). This experiment was conducted to evaluate the Ca and P bioavailabilities of green leaf meal by roos-ter. The cell wall binding Ca and P of green leaf meal such as ladino clover, alfalfa, kudzu, acacia and bush clover were collected by two stage of cutting for May and June 1990. Rooster employed in the present experiment were fed about one percentage of body weight by forced feeding of ingredient. Collection of excreta as fed after 36 hous and did not given ingredient during the determinate of urinary endogenous and metabolic fecal Ca, P and excreta for 36 hours. The feeding experiment was conducted triplication for bioassay of Ca and P and was give five repli-cation for composition of metabolic and endogenous material. The results obtained are summarized as follows : 1. The contents of neutral detergent fiber(NDF) of several green leaves meal were ranged from 30.42% to 37.28% for cutting of May and were ranged from 45.43% to 59.36% for cutting of June, there-fore NDF were decreased by abvanced stages of maturity(p<0.05). 2. The true dry matter digestibility(TDMD) of several green leaves meal were ranged from 24.57% to 42.24% for cutting of May and were ranged from 23.31% to 42.20% for cutting of June and TDMD was decreased by advanced stages of maturity(p<0.05). 3. The true available clacium(TACa) of several green leaves meal were ranged from 7.94% to 56.65% for cutting of May and were ranged from 4.02% to 51.09% for cutting of June, exception of alfalfa among other did not show increase by advanced stages of maturity(p<0.05). 4. The true avilable phosphorus(TAP) of several green leaves meal were ranged from 8.25% to 46.89% for cutting of May and were ranged from 24.86% to 42.6% for cutting of June and TAP was increased but decreased only ladino clover by advanced stages of maturity(p<0.05). 5. NDF binding of avilable calcium(NDF+Ca) of several green leaves meal were ranged from 4.04% to 15.80% for cutting of May and were ranged from 3.23% to 50 8.11% for cutting of June and they were decreased by advanced stages of maturity(p<0.05) but ladino clover and bush clover did not changed by advanced stage of maturity. 6. NDF binding of avilable phosphorus(NDF+P) of several green leaves meal were ranged from 3.97% to 17.01% for cutting of May and were ranged from 4.06% to 14.93% for cutting of June and they were decreased by advanced stages of maturity(p<0.05) but alfalfa and bush clover did not changed by advanced stage of maturity. 7. Regression equation and correlation coefficients of several green leaves meal between TDMD(Y) and NDF(X) were Y=53.5=0.42X and r=-0.50(p<0.01). 8. Regression equation and correlation coefficients of ladino clover leaf meal between digestible phos-phorus(Y) and phosphorus(X) were Y=84.5-85.1X and r=-0.91(p<0.01). 10. Regression euqation and correlation coefficients of kudzu leaf meal between digestible phosphours(Y) and phosphours(X) were Y=139-368X and r=-0.95(p<0.01). 11. Regression euqation and correlation coefficients of acacia leaf meal between digestible phosphours(Y) and phosphours(X) were Y=87.8-229X and r=-0.98(p<0.01). 12. Regression euqation and correlation coefficients of bush clover leaf meal between digestible calcium(Y) and calcium(X) were Y=17.9-12.8X and r=-0.83(p<0.05).

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.