Articles

PDF

Giant positive magnetoresistance in Fe doped In2O3 and InREO3 (RE=Eu,Nd) composites (with G. Peleckis, X. L. Wang, P. Munroe, J. Ding, and B. Lee), Faculty of Engineering - Papers (2008)

Synthesis and characterization of Fe and rare earth (RE) (RE=Eu,Nd) codoped bulk In2O3 oxide are...

 

PDF

Raman study on the effects of sintering temperature on the Jc(H) performance of MgB2 superconductor (with W. X. Li, R. H. Chen, Y. Li, M. Y. Zhu, H. M. Jin, R. Zeng, and B. Lu), Faculty of Engineering - Papers (2008)

The influence of sintering temperature on the critical transition temperature Tc and critical current density...

 

PDF

SiC and Carbon Nanotube Distinctive Effects on the Superconducting Properties of Bulk MgB2 (with G. Serrano, A. Serquis, S. Soltanian, L. Civale, B. Maiorov, T. G. Holesinger, F. Balakirev, and M. Jaime), Faculty of Engineering - Papers (2008)

This work describes in detail the simultaneous enhancement of the upper critical field (Hc2) and...

 

PDF

Effect of Carbon Substitution on the Superconducting Properties of MgB2 Doped With Multi-Walled Carbon Nanotubes and Nano Carbon (with W. K. Yeoh, J. Horvat, J. H. Kim, and X. Xu), Faculty of Engineering - Papers (2007)
We have fabricated the multiwalled carbon nanotube (MWCNT) and nano-C doped MgB2 bulk and wire...
 

PDF

Effect of Sucrose (C12H22O11) Doping on the Critical Current Density of MgB2 (with Y. Zhang, S. Zhou, and A. V. Pan), Faculty of Engineering - Papers (2007)
MgB2 bulk samples doped with sucrose were fabricated with the formula MgB2-x Cx ( x=...
 

PDF

Improvement of Upper Critical Field and Critical Current Density in Single Walled CNT Doped MgB2=Fe Wires (with J. H. Kim, W. K. Yeoh, X. Xu, and D. Q. Shi), Faculty of Engineering - Papers (2007)
We evaluated the doping effect of single walled carbon nanotubes (SWCNT) on the phase formation,...
 

PDF

Influence of Ball-Milled Low Purity Boron Powder on the Superconductivity of MgB2 (with X. Xu, J. H. Kim, W. K. Yeoh, M. Rindfleisch, M. Tomsic, and D. I. dos Santos), Faculty of Engineering - Papers (2007)
MgB2 samples were prepared using as-supplied commercial 96% boron with strong crystalline phase and the...
 

PDF

Multilayering and Ag-Doping for Properties and Performance Enhancement in YBa2Cu3O7 Films (with A. V. Pan, S. V. Pysarenko, D. Wexler, and S. Rubanov), Faculty of Engineering - Papers (2007)
Much denser YBa2Cu3O7 (YBCO) superconducting films at least 1 m thick with smooth surfaces have...
 

PDF

New Method for the Fabrication of Al-Stabilized Fe/MgB2 Wires (with A. Shcherbakov, A. V. Pan, and E. W. Collings), Faculty of Engineering - Papers (2007)
To employ Al stabilizer on Fe sheathed MgB2 wire the hot aluminizing technique was used....
 

PDF

Study of Oxygen Incorporation in PLD MgB2 Films by Rutherford Backscattering Spectroscopy (with Y. Zhao, M. Ionescu, and H. K. Liu), Faculty of Engineering - Papers (2007)
The Rutherford backscattering (RBS) method has been employed to study the incorporation of oxygen into...
 

PDF

Effect of processing temperature on high field critical current density and upper critical field of nanocarbon doped MgB2 (with W. K. Yeoh, J. Horvat, J. H. Kim, and X. Xu), Faculty of Engineering - Papers (2007)

Correlation of upper critical field (Hc2) and critical current density (Jc) with processing temperature of...

 

PDF

Large positive magnetoresistance effect below Curie temperature in In1.90 − xMn0.1SnxO3 (with X. L. Wang, G. Peleckis, R. S. Liu, and J. G. Zhu), Faculty of Engineering - Papers (2007)

We report on the magnetoresistance (MR) and magnetic properties of In1.90−xMn0.1SnxO3 (0≤x ≤0.06) oxide. All...

 

PDF

High temperature ferromagnetism in Ni-doped In2O3 and indium-tin oxide (with G. Peleckis and X. L. Wang), Faculty of Engineering - Papers (2006)
Observation of high temperature ferromagnetism in Ni-doped In2O3 and indium-tin-oxide (ITO) samples prepared by a...
 

PDF

The doping effect of multiwall carbon nanotube on MgB2/Fe superconductor wire (with J. H. Kim, W. K. Yeoh, M. J. Qin, and X. Xu), Faculty of Engineering - Papers (2006)
We evaluated the doping effect of two types of multiwall carbon nanotubes (CNTs) with different...
 

PDF

Drastic improvement of surface structure and current-carrying ability in YBa2Cu3O7 films by introducing multilayered structure (with A. V. Pan and S. Pysarenko), Faculty of Engineering - Papers (2006)
Much smoother surfaces and significantly improved superconducting properties of relatively thick YBa2Cu3O7 (YBCO) films have...
 

PDF

The effect of doping level and sintering temperature on Jc(H) performance in nano-SiC doped and pure MgB2 wires (with O. Shcherbakova, S. Soltanian, D. Wexler, M. Bhatia, M. Sumption, and E. W. Collings), Faculty of Engineering - Papers (2006)
Nanoscale SiC doped Fe/MgB2 wire samples were prepared by an in situ reaction technique using...
 

PDF

Magneto-optical imaging of the magnetization process in colossal magnetoresisitive lanthanum manganite (with A. Polyanskii, X. L. Wang, Q. W. Yao, Z. W. Lin, and J. G. Zhu), Faculty of Engineering - Papers (2006)
To gain insight into the origin of the colossal reduction of resistance in response to...
 

PDF

Quantum effects in small-capacitance high temperature superconducting tunneling junctions (with G. A. Alvarez, I. Iguchi, X. L. Wang, and Q. W. Yao), Faculty of Engineering - Papers (2006)
We investigated the effects of single electron charging energy in high temperature superconductors. Various phenomena...
 

PDF

Spectroscopic measurements of Zeeman splitting of the density of states in high temperature superconducting tunneling junctions (with G. A. Alvarez, I. Iguchi, X. L. Wang, and Q. W. Yao), Faculty of Engineering - Papers (2006)
We report c-axis tunneling spectroscopy investigations in high magnetic fields (I-V characteristics and tunneling conductance...
 

PDF

Transport properties of multilayered MgB2/Mg2Si superconducting thin film (with Y. Zhao, M. J. Qin, M. Ionescu, and P. Munroe), Faculty of Engineering - Papers (2006)
Electronic transport measurements have been carried out on superconducting MgB2/Mg2Si multilayer film, using a standard...
 

PDF

Room-temperature ferromagnetism in Mn and Fe codoped In2O3 (with G. Peleckis and X. L. Wang), Faculty of Engineering - Papers (2006)
The synthesis and characterization of polycrystalline room-temperature ferromagnetic semiconductor (In0.9Fe0.1–xMnx)2O3 (x=0–0.1) oxide are reported. All...
 

PDF

Comparison of small-field behavior in MgB2, Low- and high-temperature superconductors (with A. V. Pan), Faculty of Engineering - Papers (2006)
Different types of superconductors have been investigated at small magnetic fields Ba over wide temperature...
 

PDF

An alternative method for determination of the lock-in angle in twinned superconductors (with S. Keshavarzi, J. Horvat, A. V. Pan, M. J. Qin, X. Yao, and P. Munroe), Faculty of Engineering - Papers (2006)
An alternative method for determining the lock-in angle phiL for pinning of the vortices on...
 

PDF

Significant improvement of activation energy in MgB2/Mg2Si multilayer films (with Y. Zhao, M. Ionescu, and P. Munroe), Faculty of Engineering - Papers (2006)
We obtained a MgB2/Mg2Si multilayer structure by sequentially switching a stoichiometric MgB2 target and a...
 

PDF

Enhancement of in-field Jc in MgB2 /Fe wire using single- and multiwalled carbon nanotubes (with J. H. Kim, W. K. Yeoh, M. J. Qin, and X. Xu), Faculty of Engineering - Papers (2006)

The authors investigated the doping effects of single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes...

 

PDF

Effect of heating rates on superconducting properties of pure MgB2, carbon nanotube- and nano-SiC-doped in situ MgB2/Fe wires (with S. K. Chen, K. S. Tan, B. A. Glowacki, W. K. Yeoh, S. Soltanian, and J. Horvat), Faculty of Engineering - Papers (2005)
The influence of heating rates and annealing temperatures on the transition temperatures (Tc) and critical...
 

PDF

Absence of ferromagnetism and strong spin-orbital coupling in polycrystalline in and Co codoped Zn/sub 1-x/Co/sub 0.075/In /sub x/O oxide (with G. Peleckis and X. L. Wang), Faculty of Engineering - Papers (2005)
Polycrystalline samples of In and Co codoped ZnO (Zn/sub 1-x/In/sub x/Co/sub 0.075/O; 0.010/spl les/x/spl les/0.020)...
 

PDF

Co valence by K-edge X-ray absorption spectroscopy, magnetic properties, and structure of polycrystalline bulk Zn/sub 1-x/Co/sub x/O (with G. Peleckis, X. L. Wang, and R. S. Liu), Faculty of Engineering - Papers (2005)
We report on magnetic properties and a Co K-edge X-ray absorption spectroscopy (XAS) study of...
 

PDF

Effect of carbon nanotube size on superconductivity properties of MgB/sub 2/ (with W. K. Yeoh, J. Horvat, and P. Munroe), Faculty of Engineering - Papers (2005)
Experimental results are presented for the incorporation of carbon nanotube in polycrystalline MgB/sub 2/ superconductor...
 

PDF

Effect of Nano-Particle Doping on the Upper Critical Field and Flux Pinning in MgB2 (with S. Soltanian, W. K. Yeoh, and Y. Zhang), Faculty of Engineering - Papers (2005)
The effect of nano particle doping on the critical current density ofMgB2 is reviewed. Most...
 

PDF

Microstructures and enhancement of critical current density in YBa/sub 2/Cu/sub 3/O/sub 7/ thin films grown by pulsed laser deposition on various single crystal substrates modified by Ag nano-dots (with A. H. Li, M. Ionescu, H. K. Liu, T. Silver, and X. L. Wang), Faculty of Engineering - Papers (2005)
YBa/sub 2/Cu/sub 3/O/sub 7/ (Y123) thin films were grown by pulsed laser deposition (PLD) on...
 

PDF

Superconducting and Microstructural Properties of Two Types of MgB2 Films Prepared by Pulsed Laser Deposition (with Y. Zhao, M. Ionescu, M. Roussel, A. V. Pan, and J. Horvat), Faculty of Engineering - Papers (2005)
Significant differences in superconducting and microstructural properties between two types of MgB2 films prepared by...
 

PDF

Improvement of critical current density and thermally assisted individual vortex depinning in pulsed-laser-deposited YBa2Cu3O7–delta thin films on SrTiO3 (100) substrate with surface modification by Ag nanodots (with A. H. Li, H. K. Liu, M. Ionescu, X. L. Wang, E. W. Collings, M. D. Sumption, M. Bhatia, Z. W. Lin, and J. G. Zhu), Faculty of Engineering - Papers (2005)
YBa2Cu3O7 films were fabricated by pulsed laser deposition on SrTiO3 (100) single-crystal substrates whose surfaces...
 

PDF

Thermally assisted flux flow and individual vortex pinning in Bi2Sr2Ca2Cu3O10 single crystals grown by the traveling solvent floating zone technique (with X. L. Wang, A. H. Li, S. Yu, S. Ooi, K. Hirata, C. T. Lin, E. W. Collings, M. D. Sumption, M. Bhatia, and S. Y. Ding), Faculty of Engineering - Papers (2005)
Magnetoresisitivity and critical current density Jc as a function of temperature and field are studied...
 

PDF

Third harmonics due to surface barrier in high-temperature superconductor (with X. B. Xu, L. Zhang, X. Leng, S. Y. Ding, H. K. Liu, X. L. Wang, Z. W. Lin, and J. G. Zhu), Faculty of Engineering - Papers (2005)
The influence of surface barrier on the third harmonics ac susceptibility (chi3) is studied numerically....
 

PDF

Large upper critical field and irreversibility field in MgB2 wires with SiC additions (with M. D. Sumption, M. Bhatia, M. Rindfleisch, M. Tomsic, S. Soltanian, and E. W. Collings), Faculty of Engineering - Papers (2005)
Resistive transition measurements are reported for MgB2 strands with SiC dopants. The starting Mg powders...
 

PDF

Nanoscale-SiC doping for enhancing Jc and Hc2 in superconducting MgB2 (with V. Braccini, S. Soltanian, R. Klie, Y. Zhu, S. Li, X. L. Wang, and D. Larbalestier), Faculty of Engineering - Papers (2004)
The effect of nanoscale-SiC doping of MgB2 was investigated in comparison with undoped, clean-limit, and...
 

PDF

Characterization of LiMxFe1–xPO4 (M = Mg, Zr, Ti) Cathode Materials Prepared by the Sol-Gel Method (with G. X. Wang, S. Bewlay, J. Yao, J. H. Ahn, and H. K. Liu), Faculty of Engineering - Papers (2004)
A series of LiMxFe12xPO4 (M 5 Mg,Zr,Ti) phosphates were synthesized via a sol-gel method. Transmission...
 

PDF

Tungsten Disulfide Nanotubes for Lithium Storage (with G. X. Wang, S. Bewlay, J. Yao, and H. K. Liu), Faculty of Engineering - Papers (2004)
WS2 nanotubes were synthesized by sintering amorphous WS3 at high temperature under flowing hydrogen. High-resolution...
 

PDF

Overcritical state in superconducting round wires sheathed by iron (with A. V. Pan), Faculty of Engineering - Papers (2004)
Magnetic measurements carried out on MgB2 superconducting round wires have shown that the critical current...
 

PDF

Cryogenic magnetic field sensor based on the magnetoresistive effect in bulk Bi2212 + USr2CaO6 (with M. Ionescu, B. Winton, T. Silver, and R. Ramer), Faculty of Engineering - Papers (2004)
A large magnetoresistive (MR) effect was observed in melt-textured (MT) Bi2212 in which USr2CaO6 was...
 

PDF

Growth, microstructures, and superconductivity of Bi2–xPbxSr2Ca1–yGdyCu2O8 + z single crystals (with X. L. Wang, E. Takayama-Muromachi, A. H. Li, Z. Cheng, S. Keshavarzi, and M. J. Qin), Faculty of Engineering - Papers (2004)
Bi2–xPbxSr2Ca1–yGdyCu2O8 + delta (x = 0.34 and y = 0.18, 0.34) crystals were grown by...
 

PDF

Effects of Nanosized Adsorbing Material on Electrochemical Properties of Sulfur Cathodes for Li/S Secondary Batteries (with M. S. Song, S. C. Han, H. S. Kim, J. H. Kim, K. T. Kim, Y. M. Kang, H. J. Ahn, and J. Y. Lee), Faculty of Engineering - Papers (2004)
In order to prevent polysulfide dissolution into liquid electrolytes and to promote the Li/S redox...
 

PDF

Effect of sample size on magnetic Jc for MgB2 superconductor (with J. Horvat, S. Soltanian, and X. L. Wang), Faculty of Engineering - Papers (2004)
A strong effect of sample size on magnetic Jc(H) was observed for bulk MgB2 when...
 

PDF

Uranium Doping and Thermal Neutron Irradiation Flux Pinning Effects in MgB2 (with T. M. Silver, J. Horvat, M. Reinhard, P. Yao, S. Keshavarzi, and P. Munroe), Faculty of Engineering - Papers (2004)
The U/n method is a well-established means of improving flux pinning and critical current performance...
 

PDF

Sample-size dependence of the magnetic critical current density in MgB2 superconductors (with M. J. Qin, S. Keshavarzi, S. Soltanian, X. L. Wang, and H. K. Liu), Faculty of Engineering - Papers (2004)
Sample size dependent magnetic critical current density has been observed in magnesium diboride superconductors. At...
 

PDF

Origin of paramagnetic magnetization in field-cooled YBa2Cu3O7–delta films (with D. A. Luzhbin, A. V. Pan, V. A. Komashko, V. S. Flis, V. M. Pan, and P. Esquinazi), Faculty of Engineering - Papers (2004)
Temperature dependences of the magnetic moment have been measured in YBa2Cu3O72d thin films over a...
 

PDF

Dip effect in ac susceptibility due to surface barrier with flux creep (with X. Leng, S. Y. Ding, Y. Liu, Z. H. Wang, and H. K. Liu), Faculty of Engineering - Papers (2003)
A model is proposed to describe the effect of surface barrier (SB) on ac susceptibility...
 

PDF

Effect of carbon nanotube doping on critical current density of MgB2 superconductor (with W. K. Yeoh, J. Horvat, and M. Ionescu), Faculty of Engineering - Papers (2003)
The effect of doping MgB2 with carbon nanotubes on transition temperature, lattice parameters, critical current...
 

PDF

Effect of sample size on the magnetic critical current density in nano-SiC doped MgB2 superconductors (with S. Soltanian, M. J. Qin, S. Keshavarzi, and X. L. Wang), Faculty of Engineering - Papers (2003)
The effect of sample size on the critical current density and the flux pinning of...
 

PDF

Effects of fission-fragment damage on vortex dimensionality in silver-sheathed Bi2Sr2Ca2Cu3Ox tapes (with D. G. Marinaro and J. Horvat), Faculty of Engineering - Papers (2003)
We report on the vortex dimensionality of uranium-doped Ag/Bi2223 tapes, before and after irradiation to...
 

PDF

Superconductivity, critical current density, and flux pinning in MgB2–x(SiC)x/2 superconductor after SiC nanoparticle doping (with A. V. Pan, S. Zhou, M. Ionescu, X. L. Wang, J. Horvat, H. K. Liu, and P. R. Munroe), Faculty of Engineering - Papers (2003)
We investigated the effect of SiC nanoparticle doping on the crystal lattice structure, critical temperature...
 

PDF

Intense vortex pinning enhanced by semicrystalline defect traps in self-aligned nanostructured MgB2 (with S. Li, T. White, K. Laursen, T. T. Tan, C. Q. Sun, Z. L. Dong, Y. Li, S. H. Zho, and J. Horvat), Faculty of Engineering - Papers (2003)
In this work, we report the discovery of a vortex pinning source: semicrystalline defect wells...
 

PDF

A non-destructive, non-contact, quality test of critical current for Ag-BiSCCO tape (with A. Gandini, R. Weinstein, D. Parks, and R. Sawh), Faculty of Engineering - Papers (2003)
An accurate noncontact method of characterizing Ag-BiSCCO tape is reported, using the trapped field, B/sub...
 

PDF

Calculation of the temperature dependent AC susceptibility of superconducting disks (with M. J. Qin, G. Li, and H. K. Liu), Faculty of Engineering - Papers (2003)
The temperature dependent complex AC susceptibilities of high temperature superconducting disks in perpendicular AC magnetic...
 

PDF

Effect of grain size and doping level of SiC on the superconductivity and critical current density in MgB/sub 2/ superconductor (with S. Soltanian, X. L. Wang, J. Horvat, M. J. Qin, H. K. Liu, and P. R. Munroe), Faculty of Engineering - Papers (2003)
SiC doped MgB/sub 2/ polycrystalline samples were fabricated by in-situ reaction using different grain sizes...
 

PDF

Effects of the field dependent J/sub c/ on the vertical levitation force between a superconductor and a magnet (with G. Li, M. J. Qin, and H. K. Liu), Faculty of Engineering - Papers (2003)
The vertical levitation force between a superconductor disk (SC) and a permanent magnet disk (PM)...
 

PDF

Magnetic hysteresis and relaxation in Bi2212 single crystals doped with Fe and Pb (with K. K. Uprety, J. Horvat, X. L. Wang, G. D. Gu, M. Ionescu, H. K. Liu, and E. H. Brandt), Faculty of Engineering - Papers (2003)
Magnetic hysteresis and magnetic relaxation measurements have been performed to study vortex pinning behaviors for...
 

PDF

Magnetic shielding in MgB2/Fe superconducting wires (with J. Horvat, S. Soltanian, and X. L. Wang), Faculty of Engineering - Papers (2003)
Transport critical current (I/sub c/) was measured for MgB/sub 2//Fe round wires, with the magnetic...
 

PDF

Mechanisms of limitation and nature of field dependence of critical current in HTS epitaxial YBaCuO films (with V. M. Pan, E. A. Pashitskii, S. M. Ryabchenko, V. A. Komashko, A. V. Pan, A. V. Semenov, C. G. Tretiatchenko, and Y. V. Fedotov), Faculty of Engineering - Papers (2003)
Magnetic field and temperature dependencies of the critical current density, J/sub c/(H/spl par/c, T) were...
 

PDF

Observation of vortex distribution in samples of Bi-2223 Ag-sheathed tapes with and without uranium doping by means of the high-resolution Bitter method (with S. Ohshima, K. Ujiie, T. Kawai, K. Moriai, H. Yamada, and D. G. Marinaro), Faculty of Engineering - Papers (2003)
We examined the distribution of vortices in both Bi-2223 Ag-sheathed tape and U-doped Bi-2223 Ag-sheathed...
 

PDF

On the limiting mechanism of irradiation enhancement of I/sub c/ (with A. Gandini, R. Weinstein, D. Parks, and R. Sawh), Faculty of Engineering - Papers (2003)
Irradiation may significantly increase I/sub c/ in HTS. A systematic pattern occurs: R=I/sub c/(afterirr.)/I/sub c/(beforeirr.)...
 

PDF

Transport critical current density in Fe-sheathed nano-SiC doped MgB/sub 2/ wires (with J. Horvat, S. Soltanian, X. L. Wang, M. J. Qin, S. H. Zhou, H. K. Liu, and P. G. Munroe), Faculty of Engineering - Papers (2003)
The nano-SiC doped MgB/sub 2//Fe wires were fabricated using a powder-in-tube method and an in-situ...
 

PDF

Determination of the AC Losses of Bi-2223 HTS Coils at 77 K at Power Frequencies Using a Mass Boil-Off Calorimetric Technique (with F. Darmann and C. Cook), Faculty of Engineering - Papers (2003)
A mass boil-off measurement system has been used to accurately measure and characterize the ac...
 

PDF

Enhancement of the critical current density and flux pinning of MgB2 superconductor by nanoparticle SiC doping (with S. Soltanian, J. Horvat, X. L. Wang, S. H. Zhou, M. Ionescu, H. K. Liu, P. Munroe, and M. Tomsic), Faculty of Engineering - Papers (2002)
Doping of MgB2 by nano-SiC and its potential for the improvement of flux pinning were...
 

PDF

Intrinsic nanostructural domains: Possible origin of weaklinkless superconductivity in the quenched reaction product of Mg and amorphous B (with S. Li, O. Prabhakar, T. T. Tan, C. Q. Sun, X. L. Wang, S. Soltanian, and J. Horvat), Faculty of Engineering - Papers (2002)
Smooth modulation structure of Mg–B alloy in the quenched reaction product of Mg and amorphous...
 

PDF

Transmission electron microscopy evidence for phase transformation from Bi2Sr2CuO6 to Bi2Sr2Ca2Cu3O10 (with W. M. Chen, G. Li, S. S. Jiang, H. Y. Ling, P. Yao, M. J. Qin, and H. K. Liu), Faculty of Engineering - Papers (2002)
he growth mechanism of the Bi-2223 phase was studied using multifilamentary Ag/Bi-2223 tapes manufactured by...
 

PDF

Calculation of the hysteretic force between a superconductor and a magnet (with M. J. Qin, G. Li, H. K. Liu, and E. H. Brandt), Faculty of Engineering - Papers (2002)
The magnetic levitation forces exerted on a high-temperature superconducting HTS disk by a cylindrical permanent...
 

PDF

Order-disorder transition in Bi2.1Sr1.9CaCu2O8 + delta single crystals doped with Fe and Pb (with K. K. Uprety, J. Horvat, X. L. Wang, M. Ionescu, H. K. Liu, and E. H. Brandt), Faculty of Engineering - Papers (2002)
The magnetic field Hdis(T) where an order-disorder transition of the vortex lattice in high-Tc superconductors...
 

PDF

Synthesis of Layered-Structure LiMn1–xCrxO2 by the Pechini Method (with Z. P. Guo, S. Zhong, G. X. Wang, G. W. Walter, and H. K. Liu), Faculty of Engineering - Papers (2002)
LiMn12xCrxO2 compounds with an a-NaFeO2 layer-type crystal structure have been prepared by the Pechini method....
 

PDF

Evidence for vortex pinning induced by fluctuations in the transition temperature of MgB2 superconductors (with M. J. Qin, X. L. Wang, and H. K. Liu), Faculty of Engineering - Papers (2002)
The field-dependent critical current density jc(B) of a MgB2 bulk sample has been obtained using...
 

PDF

Improvement of critical current in MgB2 superconducting wires by a ferromagnetic sheath (with J. Horvat, X. L. Wang, and S. Soltanian), Faculty of Engineering - Papers (2002)
Transport critical current (Ic) was measured for Fe-sheathed MgB2 round wires. A critical current density...
 

PDF

Developments in high temperature superconductivity (with T. Silver, A. V. Pan, M. Ionescu, and M. J. Qin), Faculty of Engineering - Papers (2002)
The past four years (1997–2001) have seen many exciting developments in high temperature superconductivity, most...
 

PDF

Observation of heat flow at transition temperature in La1–xCaxMnO3 + delta Oxides (with Y. B. Zhang, S. Li, C. Q. Sun, W. Gao, and P. Hing), Faculty of Engineering - Papers (2001)
Heat-flow changes of La1–xCaxMnO3 + delta (x=0.25, 0.33, and 0.375) magnetoresistive oxides at their Curie...
 

PDF

Dependence of the flux-creep activation energy on current density and magnetic field for the MgB2 superconductor (with M. J. Qin, X. L. Wang, S. Soltanian, A. H. Li, and H. K. Liu), Faculty of Engineering - Papers (2001)
Systematic ac susceptibility measurements have been performed on a MgB2 bulk sample. We demonstrate that...
 

PDF

On the current transport limitations in Bi-based high temperature superconducting tapes (with S. Tonies, H. W. Weber, Y. C. Guo, R. Sawh, and R. Weinstein), Faculty of Engineering - Papers (2001)
The transport critical current densities, Jc, of superconducting (Bi, Pb)2Sr2Ca2Cu3Ox/Ag tapes were measured before and...
 

PDF

Superconductivity and flux pinning in Y and heavily Pb codoped Bi-2212 single crystals (with X. L. Wang, H. K. Liu, J. Horvat, D. Millikon, G. Heine, W. Lang, H. M. Luo, and S. Y. Ding), Faculty of Engineering - Papers (2001)
Studies of superconductivity and flux pinning were carried out on (Bi1.64Pb0.36)Sr2Ca1–xYxCu2O8 + y (x =...
 

PDF

Comparative studies on “sandwich” rolling and flat rolling in processing Ag/Bi-2223 tapes (with W. M. Chen, Y. C. Guo, X. K. Fu, H. K. Liu, and M. Apperley), Faculty of Engineering - Papers (2001)
The normal rolling method is commonly used for intermediate mechanical deformation in the powder-in-tube process...
 

PDF

Effect of the sinter-forging deformation rate on properties of Bi-2223 current leads (with X. K. Fu, Y. C. Guo, W. M. Chen, and H. K. Liu), Faculty of Engineering - Papers (2001)
The influence of the sinter-forging rate on the critical current density (Jc) behaviour in an...
 

PDF

Effect of uranium doping and thermal neutron irradiation on the flux-pinning of silver-clad Bi-Sr-Ca-Cu-O tapes (with D. Marinaro, J. Horvat, J. Boldeman, R. Weinstein, and R. Sawh), Faculty of Engineering - Papers (2001)
Ag/Bi-2223 tapes doped with small quantities of 235UO 4 powder were prepared by the powder-in-tube...
 

PDF

Improved in-field behaviour of uranium doped BiSCCO tapes by enhanced flux pinning (with S. Tonies, H. W. Weber, Y. C. Guo, R. Sawh, and R. Weinstein), Faculty of Engineering - Papers (2001)
Uranium doped BiSCCO 2223 tapes were irradiated by thermal neutrons. The resulting fission-induced defects improve...
 

PDF

Magneto-optical images of Ag/Bi-2223 tapes processed by flat rolling, “sandwich” rolling and pressing (with H. K. Liu, A. Polyanskii, W. M. Chen, Y. C. Guo, and M. Apperley), Faculty of Engineering - Papers (2001)
Magneto-optical imaging (MOI) has been used for study Ag/Bi-2223 tapes processed using flat rolling, “sandwich”...
 

PDF

Microstructural variations with uranium compound doping of Bi-Sr-Ca-Cu-O/Ag superconducting tapes (with D. A. Milliken and J. H. Ahn), Faculty of Engineering - Papers (2001)
Doping of Bi-Sr-Ca-Cu-O based silver sheathed superconducting tapes (BSCCO/Ag) with various uranium compounds was carried...
 

PDF

Synthesis of Nonstoichiometric Amorphous Mg-Based Alloy Electrodes by Mechanical Milling (with L. Sun, H. K. Liu, and D. H. Bradhurst), Faculty of Engineering - Papers (2000)
Nonstoichiometric amorphous Mg-Ni and Mg-Ni-V alloys were synthesized by mechanical milling the crystalline Mg2Ni alloy...
 

PDF

Nickel Hydroxide as an Active Material for the Positive Electrode in Rechargeable Alkaline Batteries (with J. Chen, D. H. Bradhurst, and H. K. Liu), Faculty of Engineering - Papers (1999)
Spherical nickel hydroxide powders coprecipitated with the additives Ca(OH)2, Co(OH)2, and Zn(OH)2 were prepared through...
 

PDF

Positive in-plane and negative out-of-plane magnetoresistance in the overdoped high-temperature superconductor Bi2Sr2CaCu2O8 + x (with G. Heine, W. Lang, and X. L. Wang), Faculty of Engineering - Papers (1999)
The in-plane and out-of-plane magnetoresistances of moderately overdoped Bi2Sr2CaCu2O8x single crystals have been studied from...
 

PDF

The Electrode Properties of Mg1.9Al0.1Ni0.8Co0.1Mn0.1 Alloy by Mechanical Grinding with Ni Powders (with L. Sun, H. K. Liu, and D. H. Bradhurst), Faculty of Engineering - Papers (1999)
A modified magnesium alloy of composition Mg1.9Al0.1Ni0.8Co0.1Mn0.1 was prepared by mechanical grinding with Ni powder...
 

PDF

Thermal activation and ac-field-induced discontinuous domain jumps in perovskite La0.7Ca0.3MnO3 (with X. L. Wang, J. Horvat, and H. K. Liu), Faculty of Engineering - Papers (1998)
Low-field ac susceptibility was measured on bulk La0.7Ca0.3MnO3 prepared by a partial melting technique. Discontinuous...
 

PDF

Magnetic and superconducting properties of Pr in La12xPrxBaCaCu3O7 system with 0.0< x <1.0 (with V. P. S. Awana, R. Singh, A. V. Narlikar, S. K. Malik, and W. B. Yelon), Faculty of Engineering - Papers (1998)

We report the results on structural aspects, magnetic, and superconducting properties of the La1-xPrxBaCaCu3O7 system....

 

PDF

Structural and magnetic properties of RSr2Fe3O9 (R=La, Y, Pr, and Gd) (with V. P. S. Awana, I. Felner, I. Nowik, S. K. Malik, A. Mehta, R. Singh, A. V. Narlikar, and W. B. Yelon), Faculty of Engineering - Papers (1998)

We have investigated the RSr2Fe3O9 (R=La, Y, Pr, and Gd) materials by several experimental techniques,...

 

PDF

Anomalous magnetization peak effect in spiral-grown Bi2Sr2CaCu2Oy crystals (with X. L. Wang, J. Horvat, H. K. Liu, and J. N. Li), Faculty of Engineering - Papers (1997)
Magnetic hysteresis loops were measured on spiral-grown Bi2Sr2CaCu2Oy Bi-2212 crystals. An anomalous peak effect at...
 

PDF

Intergranular and intragranular critical currents in silver-sheathed Pb-Bi-Sr-Ca-Cu-O tapes (with K. Muller, C. Andrikidis, and H. K. Liu), Faculty of Engineering - Papers (1994)
The role of the intergranular and intragranular critical current densities in silver-sheathed Pb-Bi-Sr-Ca-Cu-O tapes is...
 

PDF

Magnetoresistance and V-I curves of Ag-sheathed (Bi,Pb)2Sr2Ca2Cu3O10+y tape (with E. Babic, I. Kusevic, H. K. Liu, and Q. Y. Hu), Faculty of Engineering - Papers (1994)
The magnetoresistance and the V-I curves (I>Ic) of a well-characterized Ag-clad (Bi,Pb)2Sr2Ca2Cu3O10+y tape (BPSCCO) with...
 

Presentations

PDF

Electrical and Optical Properties of La0.7Ca0.3MnO3 Polycrystalline and Thin Film (with F. Gao, R. A. Lewis, M. Ionescu, and X. L. Wang), Faculty of Engineering - Papers (2008)

The La0.7Ca0.3MnO3 thin film shows a metal-insulator transition at temperature around 150 K, about 100...

 

PDF

Absence of ferromagnetism and strong orbital coupling in carrier rich Zn/sub 1-x/In/sub x/Co/sub 0.075/O (with X. L. Wang and G. Peleckis), Faculty of Engineering - Papers (2005)
Polycrystalline samples of Zn/sub 1-x/In/sub x/Co/sub 0.075/O (0.010/spl les/x/spl les/0.020) diluted magnetic semiconductors were prepared...
 

PDF

Co valence and possible spin transformation in diluted magnetic semiconductors Zn/sub 1-z/Mg/sub z/Co/sub 0.15/O and Zn/sub 1-x/Co/sub x/O (with G. Peleckis, X. L. Wang, and R. S. Liu), Faculty of Informatics - Papers (2005)
In this paper, possible spin transformation and Co valence in dilute magnetic semiconductors is...
 

PDF

Infrared-active phonons of HoMn/sub 1-x/Co/sub x/O/sub 3/ (x = 0-0.8) (with F. Gao, X. L. Wang, M. Farhoudi, and R. A. Lewis), Faculty of Engineering - Papers (2005)
Polycrystalline HoMn/sub 1-x/Co/sub x/O/sub 3/ was synthesized by solid-state reaction. The infrared active phonons of...