Effects of the Zr concentration on transparent Y2O3 ceramics fabricated by vacuum pre-sintering and a subsequent HIP treatment

Zhu, L. L.,Park, Y. J.,Gan, L.,Go, S. I.,Kim, H. N.,Kim, J. M.,Ko, J. W. Chapman and Hall 2017 Journal of materials science Materials in electron Vol. No.

<P>Highly transparent Y2O3 ceramics doped with different Zr concentrations were successfully fabricated by vacuum pre-sintering at temperatures ranging from 1600 to 1800 degrees C combined with a subsequent hot-isostatic pressing (HIP) treatment using commercial powders as the starting materials. All of the 1 mol% Zr-doped Y2O3 ceramics exhibit very good optical quality. The sample with the highest transparency level was realized by vacuum sintering at 1650 degrees C for 4 h followed by a post-HIP treatment at 1450 degrees C lasting 5 h. It has a fine microstructure and the grain size is 1.48 mu m. Furthermore, the in-line transmittance reaches 83.3% at 1100 nm (1.2 mm thickness). It was found that a relatively low vacuum sintering temperature (1650 degrees C) and relatively low Zr doping concentration (1 mol%) are more appropriate to achieve optimally transparent Y2O3 ceramics with a subsequent HIP treatment.</P>

Thermoelectric properties of Gd, Y co-doped Ca3Co4O9+δ

H.Q. Liu,X.B. Zhao,T.J. Zhu,Y. Song,F.P. Wang 한국물리학회 2009 Current Applied Physics Vol.9 No.3

The Ca3-x-yGdxYyCo4O9+δ precursor powders were synthesized by the polyacrylamide gel method. The powders were sintered by the spark plasma sintering (SPS). The DTA analysis showed that the synthesis temperature of Ca3Co4O9+δ was about 933 K, which is lower than that of the conventional citric acid method. The resistivities, the Seebeck coefficients and the thermal conductivities of the samples were measured from room temperature to 973 K. The Seebeck coefficients and the resistivities of the doped samples were remarkably enhanced due to the decrease of the carrier concentration, whereas the thermal conductivities of them were decreased due to the impurity scattering effect. The maximal ZT value of 0.26 was obtained at 973 K for Ca2.7 Gd0.15 Y0.15Co4O9+δ. The Ca3-x-yGdxYyCo4O9+δ precursor powders were synthesized by the polyacrylamide gel method. The powders were sintered by the spark plasma sintering (SPS). The DTA analysis showed that the synthesis temperature of Ca3Co4O9+δ was about 933 K, which is lower than that of the conventional citric acid method. The resistivities, the Seebeck coefficients and the thermal conductivities of the samples were measured from room temperature to 973 K. The Seebeck coefficients and the resistivities of the doped samples were remarkably enhanced due to the decrease of the carrier concentration, whereas the thermal conductivities of them were decreased due to the impurity scattering effect. The maximal ZT value of 0.26 was obtained at 973 K for Ca2.7 Gd0.15 Y0.15Co4O9+δ.

Induction of leukemic-cell-specific cytotoxic T lymphocytes by autologous monocyte-derived dendritic cells presenting leukemic cell antigens

Lee, J.-J.,Park, M.-S.,Park, J.-S.,Kang, H.-K.,Kim, S.-K.,Nguyen Pham, T.-N.,Zhu, X.-W.,Cho, D.,Nam, J.-H.,Kim, Y.-J.,Rhee, J.-H.,Chung, I.-J.,Kim, H.-J. Wiley-Liss 2006 JOURNAL OF CLINICAL APHERESIS Vol.21 No.3

<P>Leukemic-dendritic cells (leukemic-DCs) have certain limitations, which include difficult generation in 30–40% of patients, and low levels of expression of several key molecules. Therefore, an alternative approach using monocyte-derived DCs pulsed with tumor antigens is required. We investigated the possibility of immunotherapy for AML using leukemic-cell-specific cytotoxic T lymphocytes that were stimulated in vitro by autologous DCs pulsed with tumor antigens. To generate DCs, CD14+ cells were isolated from peripheral blood mononuclear cells using magnetic-activated cell sorting, and cultured in the presence of GM-CSF and IL-4. On day 6, maturation of DCs was induced by addition of cytokine cocktail (TNF-&agr;, IL-1&bgr;, IL-6, and prostaglandin E<SUB>2</SUB>) for 2 days, and then the mature DCs were pulsed with whole leukemic cell lysates or apoptotic leukemic cells. There were no differences in the phenotypic expressions of mature DCs generated by pulsing with or without leukemic antigens. The mature DCs pulsed with tumor cell lysates or apoptotic leukemic cells showed a higher allostimulatory capacity for allogeneic CD3+ T cells as compared with mature non-pulsed DCs. Autologous CD3+ T cells stimulated by the mature pulsed DCs showed more potent cytotoxic activities against autologous leukemic cells than those stimulated by mature non-pulsed DCs. These results suggest that use of DCs pulsed with leukemic cell lysates or apoptotic leukemic cells is a feasible alternative immunotherapeutic approach to overcome the limitations of leukemic-DCs for the treatment of AML patients. J Clin Apheresis 2006. © 2006 Wiley-Liss, Inc.</P>

A self-assembled amphiphilic imidazolium-based ATP probe

Zhu, J. H.,Yu, C.,Chen, Y.,Shin, J.,Cao, Q. Y.,Kim, J. unknown 2017 Chemical communications Vol. No.

<P>A novel amphiphilic imidazolium-based probe containing a dansyl fluorophore and a long cetyl chain has been developed for ATP recognition. The probe forms self-assembled micelle-like aggregates at low concentration in its aqueous solution and can selectively recognize ATP among other bioactive anions with a significant enhancement in fluorescence emission.</P>

Strain-modulated antiferromagnetic spin orientation and exchange coupling in Fe/CoO(001)

Zhu, J.,Li, Q.,Li, J. X.,Ding, Z.,Hua, C. Y.,Huang, M. J.,Lin, H.-J.,Hu, Z.,Won, C.,Wu, Y. Z. American Institute of Physics 2014 JOURNAL OF APPLIED PHYSICS - Vol.115 No.19

The effect of CoO spin orientation on exchange coupling was investigated in single-crystalline Fe/CoO/MnO/MgO(001) systems. An antiferromagnetic CoO spin reorientation transition from the in-plane direction to the out-of-plane direction was found to be associated with the in-plane strain transition in CoO film from compression to expansion. The induced uniaxial anisotropies by exchange coupling at the Fe/CoO interface are significantly stronger for the in-plane CoO spin orientation than for the out-of-plane CoO spin orientation. Our study provides a way to modify the exchange coupling in the ferromagnetic (FM)/antiferromagnetic (AFM) bilayer by modulating the strain in the AFM film. (C) 2014 AIP Publishing LLC.

Linkage Disequilibrium Estimation of Chinese Beef Simmental Cattle Using High-density SNP Panels

Zhu, M.,Zhu, B.,Wang, Y.H.,Wu, Y.,Xu, L.,Guo, L.P.,Yuan, Z.R.,Zhang, L.P.,Gao, X.,Gao, H.J.,Xu, S.Z.,Li, J.Y. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.6

Linkage disequilibrium (LD) plays an important role in genomic selection and mapping quantitative trait loci (QTL). In this study, the pattern of LD and effective population size ($N_e$) were investigated in Chinese beef Simmental cattle. A total of 640 bulls were genotyped with IlluminaBovinSNP50BeadChip and IlluminaBovinHDBeadChip. We estimated LD for each autosomal chromosome at the distance between two random SNPs of <0 to 25 kb, 25 to 50 kb, 50 to 100 kb, 100 to 500 kb, 0.5 to 1 Mb, 1 to 5 Mb and 5 to 10 Mb. The mean values of $r^2$ were 0.30, 0.16 and 0.08, when the separation between SNPs ranged from 0 to 25 kb to 50 to 100 kb and then to 0.5 to 1 Mb, respectively. The LD estimates decreased as the distance increased in SNP pairs, and increased with the increase of minor allelic frequency (MAF) and with the decrease of sample sizes. Estimates of effective population size for Chinese beef Simmental cattle decreased in the past generations and $N_e$ was 73 at five generations ago.

Formation Processes of Exciton in AlGaAs / GaAs Quantum Well Structure

J. B. Zhu,H. J. Jeon,E. K. Suh,H. J. Lee,Y. G. Hwang 대한전자공학회 1995 대한전자공학회 학술대회 Vol.1995 No.1

Effects of Supplemental Levels of Saccharomyces cerevisiae Fermentation Product on Lactation Performance in Dairy Cows under Heat Stress

Zhu, W.,Zhang, B.X.,Yao, K.Y.,Yoon, I.,Chung, Y.H.,Wang, J.K.,Liu, J.X. Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.6

The objectives of this study were to evaluate the effects of different supplemental levels of Saccharomyces cerevisiae fermentation product (SCFP; Original XP; Diamond V) on lactation performance in Holstein dairy cows under heat stress. Eighty-one multiparous Holstein dairy cows were divided into 27 blocks of 3 cows each based on milk yield ($23.6{\pm}0.20kg/d$), parity ($2.88{\pm}0.91$) and day in milk ($204{\pm}46d$). The cows were randomly assigned within blocks to one of three treatments: 0 (control), 120, or 240 g/d of SCFP mixed with 240, 120, or 0 g of corn meal, respectively. The experiment was carried out during the summer season of 2014, starting from 14 July 2014 and lasting for 9 weeks with the first week as adaption period. During the experimental period, average daily temperature-humidity index (measured at 08:00, 14:00, and 20:00) was above 68, indicating that cows were exposed to heat stress throughout the study. Rectal temperatures tended to decrease linearly (p = 0.07) for cows supplemented with SCFP compared to the control cows at 14:30, but were not different at 06:30 (p>0.10). Dry matter intake was not affected by SCFP supplementation (p>0.10). Milk yield increased linearly (p<0.05) with increasing levels of SCFP. Feed efficiency (milk yield/ dry matter intake) was highest (p<0.05) for cows fed 240 g/d SCFP. Cows supplemented with SCFP gained (p<0.01) body weight, while cows in the control lost body weight. Net energy balance also increased linearly (p<0.01) with increasing levels of SCFP. Concentrations of milk urea nitrogen (p<0.01) decreased linearly with increasing levels of SCFP, while no difference (p>0.10) was observed among the treatments in conversion of dietary crude protein to milk protein yield. In summary, supplementation of SCFP alleviated the negative effect of heat stress in lactating Holstein dairy cows and allowed cows to maintain higher milk production, feed efficiency and net energy balance. Effects of SCFP were dose-dependent and greater effects were observed from higher doses.

HIGH-PERFORMANCE Pt/CNTs CATALYSTS VIA HYDROGEN PLASMA FOR METHANOL ELECTROOXIDATION

J. L. XU,S. G. WANG,Q. R. DENG,Y. LIU,J. L. ZHU,C. B. XU,J. H. WANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

High-performance carbon nanotubes-supported Pt catalysts (Pt/CNTs) catalysts were pre-pared on the basis of Pt precursors reduced by hydrogen plasma (Pt/CNTs-HP) generated bymicrowave. The other two Pt/CNTs catalysts prepared by hydrogen (Pt/CNTs-H) and NaBH 4(Pt/CNTs-N) reduction were also involved for comparison. The practical composition of thecatalysts was characterized with energy dispersive analysis of X-ray (EDAX). It was shown fromtransmission electron microscopy (TEM) and X-ray di®raction (XRD) that the Pt nanoparticlesin Pt/CNTs-HP were uniformly dispersed on CNTs with smaller particle size around 2 nmand narrower size distribution as compared with the other two catalysts. Additionally, X-rayphotoelectron spectrum (XPS) analysis indicated higher amount of zero-valence states of Pt inPt/CNTs-HP caused by hydrogen plasma treatment. The electrooxidation of liquid methanol onthese catalysts was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV)and chronoamperometry. The long-time durability is very comparable to all the three catalysts. Remarkably, the Pt/CNTs-HP possessed the highest electrocatalytic activity, suggesting thatthe hydrogen plasma reduction approach can be a promising reduction method for preparinghigh-performance Pt-based electrocatalysts.

Volume contribution of exchange-coupling-induced uniaxial anisotropy in Fe/CoO/MgO(001) system

Zhu, J.,Li, Q.,Li, J. X.,Ding, Z.,Won, C. Y.,Wu, Y. Z. American Institute of Physics 2013 JOURNAL OF APPLIED PHYSICS - Vol.114 No.17