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.

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.

젖산나트륨 첨가와 젖산 침지가 비엔나 소세지의 품질 및 관능상에 미치는 영향

김영환,박구부,진상근,신택순,박범영,김영직 한국축산학회 1995 한국축산학회지 Vol.37 No.4

This study was conduct to investigate the interactive effects of sodium lactate addition and lactic acid dipping on the shelf life of Vienna sausage. Three kinds of Vienna sausages were macwfacaured as the control (addition of potassium sorbate and dipping in fumaric acid solution), treatment A(addition of sodium lactate and dipping in fumaric acid solution) and treatment B(addition of sodium lactate and dipping in lactic acid). They were divided into two groups and one group was stored at 5℃ for 6 weeks and the other one at 20℃ for 4 weeks. The physico-chemical properties of sausages were exanuned during the storage time. $quot;Ihe results are summarized as follows: 1. At both storage temperatures, lactic acid contents of treatment A and B were significantly (P$lt;0.05) higher than that of control. As storage period passed, it was significantly (P$lt;0.05) decreased in all treatments. Also, the decreasing rates of control and at 20℃ were higher than those of treatment A, B and at 5℃. 2. Jelly strength was low in the order of control, treatment A and B at both storage temperatures. Jelly strengths of control and treatment A were higher at the end of the storage compared to at the initial stage of the storage but treatment B was lower. It was lower at 30℃ than at 5℃. 3. At both storage temperatures, treatment B and control showed significantly (P$lt;0.05) higher $quot;L$quot; value than that of treatment A but lower $quot;a$quot; value, $quot;b$quot; value was decreased in the order of control, treatment A and B. $quot;L$quot; and $quot;a$quot; value were significantly (P$lt;0.05) decreased with storage period in all treatments but $quot;b$quot; value showed a increasing tendency. Treatment B showed intense discoloration compared to other treatments at 20℃. 4. In sensory panel score, there was a difference between control and treatment B and the difference was more obvious at 20℃ than at 5℃. From the results mentioned so far, it was shown that, treatment A maintained similar product quality to control at both storage temperatures white treatment B only at 5℃.

200 GeV/핵자 유황이온과 핵건판핵의 충돌에 의해 생성된 헬륨 파쇄핵의 극한파쇄 연구

김동철,송진섭,윤천실,정성헌,박인곤,김종오,김철수,김태연,이승희,조재희,천병구,김재률,김준원,김태익,박명렬,장한일,임인택 慶尙大學校 기초과학연구소 1992 基礎科學硏究所報 Vol.8 No.-

고에너지 중이온 원자핵과 핵건판의 충돌에서, 200GeV/핵자 유황이온에 의해 생성된 파쇄 헬륨핵(Z=2)의 실험실계의 방출각 분포는 표적핵에 무관한 회귀공식. dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)]로 잘 표현된다. 여기에서 의사신속도 η=-ln[tan(θ/2)]이고, y_b는 실험실계의 입사입자(^32S)의 신속도이다. 이 공식에 의한 적합에서 k=-0.057±0.008로 얻어진다. 즉, 핵건판과 고에너지 중이온의 충돌에서 파쇄 헬륨핵의 exp(η-y_b)의 분포는 "극한파쇄" 현상을 잘 설명하고 있다. The angular distribution of emission angle θ of helium (Z=2) produced in the collisions of incident particles of 200 GeV/nucleon ^32S in nuclear emulsion is well expressed by dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)] where the pseudorapidity is η=-ln[tan(θ/2)], the laboratory system primary rapidity is y_b, and k=-0.057+0.008. The shape of this frequency of occurrence distributions in terms of exp(η-y_b) attests to the validity of the concept of "limiting fragmentation" for helium projectile fragments produced in the projectile fragmentation regions of heavy ion collisions in nuclear emulsion.

The synergistic effects of combined NaOCl, gamma irradiation and vitamin B₁ on populations of Aeromonas hydrophila in squid

Park, S.Y.,Kim, B.Y.,Song, H.H.,Ha, S.D. Butterworths ; Taylor Francis ; Elsevier Science 2012 Food control Vol.27 No.1

The present study investigated the synergistic disinfection effects of combined NaOCl/gamma irradiation and NaOCl/vitamin B<SUB>1</SUB> treatment against Aeromonas hydrophila ATCC 7966 in tryptic soy broth (TSB) and squid. The synergistic effects were not dependent on the concentration of NaOCl or the dose of gamma irradiation, but were dependent on the vitamin B<SUB>1</SUB> concentration. Synergistic values for NaOCl/gamma irradiation treatment in TSB and squid were -0.37 to 2.09 log<SUB>10</SUB> CFU/mL and 0.00-2.92 log<SUB>10</SUB> CFU/g, respectively. The largest synergistic values, 2.09 log<SUB>10</SUB> CFU/mL in TSB and 2.92 log<SUB>10</SUB> CFU/g in squid, were as a result of treatment with a combination of 40 ppm NaOCl and 1.0 kGy gamma irradiation and 80 ppm NaOCl and 2.0 kGy gamma irradiation, respectively. Synergistic values for NaOCl/vitamin B<SUB>1</SUB> treatment in TSB and squid were 0.59-2.98 log<SUB>10</SUB> CFU/mL and 0.06-1.35 log<SUB>10</SUB> CFU/g, respectively. The largest synergistic values, 2.98 log<SUB>10</SUB> CFU/mL in TSB and 1.35 log<SUB>10</SUB> CFU/g in squid, were as a result of treatment with a combination of 300 ppm NaOCl and 1000 ppm vitamin B<SUB>1</SUB> and 1000 ppm NaOCl and 1000 ppm vitamin B<SUB>1</SUB>, respectively. The results in the broth study suggest that the combination of 40 ppm NaOCl and 1.0 kGy gamma irradiation and 300 ppm NaOCl and 1000 ppm vitamin B<SUB>1</SUB> could be regarded as a potential optimum hurdle approach for application to real target foods and(or) food surfaces for the control of A. hydrophila. Moreover, the results in the food study indicate that the combination treatment of 80 ppm NaOCl and 2.0 kGy gamma irradiation and 100 ppm NaOCl and 1000 ppm vitamin B<SUB>1</SUB> could possibly be used in seafood production, processing, and distribution processes to enhance seafood safety.

Effects of oxide coating on the growth of single grain YBCO bulk superconductors

Park, S.D.,Jun, B.H.,Park, B.J.,Jung, S.Y.,Seong, B.S.,Kim, C.J. North-Holland 2009 Physica. C, Superconductivity Vol.469 No.15

Surface oxide coating and bottom inserting of oxide plates have been conducted to top seeded melt growth (TSMG) processed YBa<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7-y</SUB> (Y123) bulk superconductors with an aim of controlling the Y123 nucleation and growth. The coating medium for surfaces was Yb<SUB>2</SUB>O<SUB>3</SUB> solution and the bottom inserts were Yb<SUB>2</SUB>O<SUB>3</SUB>/Y<SUB>2</SUB>O<SUB>3</SUB> powder compact. Many vertical cracks were found to develop at the compact/insert interfaces when an Yb<SUB>2</SUB>O<SUB>3</SUB> insert was used, but the crack evolution was greatly reduced when a (Yb<SUB>2</SUB>O<SUB>3</SUB>+Y<SUB>2</SUB>O<SUB>3</SUB>) insert was used. The formation of the vertical cracks is ascribed to the difference in thermal expansion between the YBCO compact and bottom insert. Presence of vertical cracks was found to be crucial to the trapped magnetic field and levitation forces of single grain YBCO bulk superconductors. The Y123 nucleation and growth in TSMG-processed YBCO bulk superconductors were successfully controlled by conducting surface coating and bottom plating using a (Yb<SUB>2</SUB>O<SUB>3</SUB>+Y<SUB>2</SUB>O<SUB>3</SUB>) insert and as a result, the levitation properties were much enhanced.

Expression of mosquitocidal crystal protein genes in non-insecticidal Bacillus thuringiensis subsp. israelensis

Gill, S.S.,Oh, H.W.,Lee, D.W.,Roh, J.Y.,Park, H.W.,Jin, B.R.,Je, Y.H.,Kang, S.K. 東亞大學校附設遺傳工學硏究所 1998 遺傳工學硏究 Vol.- No.5

J.Y.ROH,H.W.PARK,Y.H.JE,D.W.LEE,B.R.JIN, H.W.OH,S.S.GILL AND S.K.KANG.1997. Bacillus thuringiensis NTB-1 isolated from soil samples in Korea produces ovoidal parasporal inclusions with proteins of approximately 24-40kDa in size. Although serological study indicated that the isolate has a flagella (H) antigen identical with subsp. israelensis, it seemed to be non-insecticidal against Lepidoptera and Coleoptera as well as Diptera. To investigate the activity of non-insecticidal B.thuringiensis transformed with insecticidal crystal protein genes, cryIVD and cytA genes of B. thuringiensis subsp. morrisoni PG-14, highly toxic to mosquito larvae, were introduced into the isolate NTB-1. The expression of mosquitocidal crystal protein genes in NTB-1 was characterized by SDS-PAGE analysis and electron microscopy. The results showed that crystalline inclusions of host, CryIVD and CytA were stably expressed in the transformant. However, the mosquitocidal activity of transformant was similar to that of B. thuringiensis subsp. kurstaki Cry-B harbouring cryIVD and cytA genes, demonstrating that a synergistic effect by an interaction of both introduced insecticidal and resident non-insecticidal crystal proteins was not observed.

ASK1/JNK-mediated TAp63 activation controls the cell survival signal of baicalein-treated EBV-transformed B cells

Park, G. B.,Kim, Y. S.,Lee, H. K.,Yang, J. W.,Kim, D.,Hur, D. Y. Springer Science + Business Media 2016 MOLECULAR AND CELLULAR BIOCHEMISTRY - Vol.412 No.1

<P>Transcriptionally active p63 (TAp63) promotes cell cycle arrest, senescence, and apoptosis in several cancer cells. Migration inhibitory factor (MIF)/CD74 regulates B-cell survival through nuclear factor (NF)-kappa B-dependent TAp63 expression. In this study, we investigated how the level of TAp63 expression influences the induction of apoptosis in baicalein-treated EBV-transformed B cells. Baicalein induced the expression of TAp63 and apoptosis signal-regulating kinase 1 (ASK1), as well as cytotoxicity, by disrupting the mitochondrial membrane and inhibiting the activation of phosphoinositide 3-kinase (PI3K)/Akt and NF-kappa B. Genetic knockdown of TAp63 or ASK1 by small interfering RNA resulted in protection from apoptosis accompanied by the recovery of CD74, CD44, alpha 4 integrin, Bcl-2, and NF-kappa B activation. Baicalein-induced reactive oxygen species activated the ASK1/JNK pathway with subsequent expression of TAp63. Pre-engagement with MIF/CD74 maintained the expression of CD74, CD44, and alpha 4 integrin, as well as Syk/Src-mediated PI3K/Akt activation, in baicalein-treated EBV-transformed B cells. Meanwhile, ASK1/JNK-dependent TAp63 expression was efficiently suppressed after pre-treatment with MIF. Our results suggest that baicalein-mediated ASK1/JNK activation regulates the mitochondria-dependent apoptosis pathway through the up-regulation of TAp63 and downregulation of NF-kappa B and CD74/CD44 in B-cell malignancies.</P>

INFLUENCE OF B AND Nd CONTENT ON THE MAGNETIC PROPERTIES OF α-Fe BASED NdFeB MAGNETS WITH ULTRAFINE GRAINS

Y.S. Cho,Y.B. Kim,W.S. Park,C.S. Kim,T.K. Kim 한국자기학회 1995 韓國磁氣學會誌 Vol.5 No.5

The influence of Nd and B contents on the magnetic properties and structures of α-Fe based Nd-(Fe, Co)B-Mo-Cu alloys was investigated. Nd₄(Fe_(0.9)Co_(0.1))_(92-x)BxMo₃Cu₁ and Nd_x(Fe_(0.9)Co_(0.1))_(86-x)B_(10)Mo₃Cu₁ amorphous alloys prepared by rapid solidification process were crystallized to form nanocrystalline structure. The increase of B content in Nd₄(Fe_(0.9)Co_(0.1))_(92-x)BxMo₃Cu₁ nanocrystalline resulted in the change of structure of soft phase in the sequence of α-Fe → α-Fe+Fe₃B → Fe₃B. The coercivitis of the alloys were increased with increasing B content and was 263 kA/m at x=18. On the contrary, the remanence has shown an opposite trends. The increase of Nd content in Nd_x(Fe_(0.9)Co_(0.1))_(86-x)B_(10)Mo₃Cu₁ nanocrystalline containing α-Fe as main phase had no effect on the structure and improved coercivity up to 256 kA/m. However, the remanence was decreased from 1.4 T to 1.15 T according to the increase of Nd content.

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.