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Full-Text Articles in Engineering

Effect Of Boron Powder Purity On Superconducting Properties Of Mgb2, Xun Xu, Meng J. Qin, Konstantin K. Konstantinov, Dayse Dos Santos, Wai Kong Yeoh, Jung Ho Kim, S. X. Dou Jan 2006

Effect Of Boron Powder Purity On Superconducting Properties Of Mgb2, Xun Xu, Meng J. Qin, Konstantin K. Konstantinov, Dayse Dos Santos, Wai Kong Yeoh, Jung Ho Kim, S. X. Dou

Faculty of Engineering - Papers (Archive)

The effect of the properties of starting boron powders on the superconducting properties of MgB2 has been studied. The 92% and 96% pure powders produce lower surface reactivity and larger particle size than the 99% boron powder, as can be seen from Brunauer–Emmett–Teller (BET) and scanning electron microscopy (SEM) results, indicating that the low purity powders cannot be used to archive the same superconducting properties as those of samples made from pure 99% boron powder. However, the purity of 92% and 96% boron powders can be improved by using a simple chemical process, leading to enhanced magnetic critical current …


Effect Of Particle Composition On Consolidation Of Hot Briquetted Iron, Wanda Melfo, Rian J. Dippenaar, Brian J. Monaghan Jan 2006

Effect Of Particle Composition On Consolidation Of Hot Briquetted Iron, Wanda Melfo, Rian J. Dippenaar, Brian J. Monaghan

Faculty of Engineering - Papers (Archive)

The influence of the carbon concentration of directly reduced iron (DRI) powders on the compressibility and fracture strength of hot briquetted iron (HBI) has been studied. Industrially produced DRI, pure iron powder and Fe–C alloy powders (synthetic DRI) were used in the study. It was found that the mechanism of compaction could be attributed to pure yielding. The pressure required to attain a given density increased proportionally with the carbon content. The morphology and phases present in DRI powder had a significant influence on the compressibility. The fracture strength of the compacts increased with increasing carbon content of the DRI …


Effect Of Changing Slag Composition On Spinel Inclusion Dissolution, Brian J. Monaghan, Liang Chen Jan 2006

Effect Of Changing Slag Composition On Spinel Inclusion Dissolution, Brian J. Monaghan, Liang Chen

Faculty of Engineering - Papers (Archive)

The rate of MgAl2O4 spinel inclusion dissolution in CaO–SiO2–Al2O3 slags at 1504uC has been measured using a laser scanning confocal microscope. It was found that the mechanism of spinel inclusion dissolution was at least in part controlled by mass transfer in the slag phase for the slag compositions used. Evidence in support of this finding was that the calculated diffusion coefficient was inversely proportional to the slag viscosity and that the diffusion coefficients were in reasonable agreement with those obtained in a separate study on alumina dissolution. The diffusion coefficients obtained were in the range of 0.76–2.2610210 m2 s21.


The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic Jan 2006

The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a study of Swedish regional small businesses which investigated the barriers to E-commerce adoption (amongst other things). The aim of the paper is twofold: to examine the correlation between barriers to E-commerce adoption in order to identify underlying factors: and to determine whether these differ between SMEs that are members of a small business cluster and SMEs that are not. The paper begins by examining the nature of SMEs and identifying features that are unique to SMEs. A discussion of barriers to E-commerce adoption based on previous research is then presented and the barriers are mapped to …


The Effect Of Oxidation On The Structure Of Styryl-Substituted Sexithiophenes: A Resonance Raman Spectroscopy And Density Functional Theory Study, Tracy Clarke, Keith Gordon, David L. Officer, Daina K. Grant Jan 2006

The Effect Of Oxidation On The Structure Of Styryl-Substituted Sexithiophenes: A Resonance Raman Spectroscopy And Density Functional Theory Study, Tracy Clarke, Keith Gordon, David L. Officer, Daina K. Grant

Australian Institute for Innovative Materials - Papers

The structures and vibrational properties of a series of styryl-substituted sexithiophenes and their charged species have been examined using resonance Raman spectroscopy in conjunction with density functional theory calculations. The calculated geometries of the radical cations and dications indicate that the quinoidal charged defects are more strongly localized in the center of the thiophene backbone than is observed in other sexithiophenes. This defect confinement, induced by the positions of the styryl substituents, is particularly evident in the dication species. However, the defect confinement weakens when alkoxy groups are added onto the phenyl rings by causing the extension of the charged …