Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Faculty of Engineering and Information Sciences - Papers: Part A

Carbon

Articles 31 - 39 of 39

Full-Text Articles in Engineering

Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez Jan 2011

Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez

Faculty of Engineering and Information Sciences - Papers: Part A

Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.


Computational Intelligence For Carbon-Centric Computing, John Fulcher Jan 2010

Computational Intelligence For Carbon-Centric Computing, John Fulcher

Faculty of Engineering and Information Sciences - Papers: Part A

The focus of this paper is twofold: firstly we make a case for the use of Computational Intelligence (CI) techniques in the modelling and/or prediction of global weather, CO2 emissions, climate change and similar endeavours. CI exploits processes found in Nature, albeit by way of software simulations on digital computers (i.e. in silico), and excel in particular at pattern recognition and/or classification. Moreover, they are characterized as being non-algorithmic, bottom-up, data-driven, and learn-by-example. The second focus of this paper is to propose the use of carbonrather than silicon-based computing, specifically in the form of DNA (or molecular) computing. Notwithstanding the …


Berkovich Indentation Of Diamondlike Carbon Coatings On Silicon Substrates, Ayesha J. Haq, Paul Munroe, Mark Hoffman, Phil Martin, Avi Bendavid Jan 2008

Berkovich Indentation Of Diamondlike Carbon Coatings On Silicon Substrates, Ayesha J. Haq, Paul Munroe, Mark Hoffman, Phil Martin, Avi Bendavid

Faculty of Engineering and Information Sciences - Papers: Part A

The deformation behavior of diamondlike carbon (DLC) coatings on silicon substrates induced by Berkovich indentation has been investigated. DLC coatings deposited by a plasma-assisted chemical vapor deposition technique were subjected to nanoindentation with a Berkovich indenter over a range of maximum loads from 100 to 300 mN. Distinct pop-ins were observed for loads greater than 150 mN. However, no pop-out was observed for the loads studied. The top surface of the indents showed annular cracks with associated fragmented material. The cross sections showed up to 20% localized reduction in thickness of the DLC coating beneath the indenter tip. Cracking, {111} …


A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill Jan 2007

A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill

Faculty of Engineering and Information Sciences - Papers: Part A

A new structural model accounts for the curvature inherent in their cylindrical shape.


Atomic Observations Of Warm Rolled Low Carbon Steels Alloyed With Cr And P, E V. Pereloma, M K. Miller Jan 2005

Atomic Observations Of Warm Rolled Low Carbon Steels Alloyed With Cr And P, E V. Pereloma, M K. Miller

Faculty of Engineering and Information Sciences - Papers: Part A

Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005


Widmanstatten Ferrite Plate Formation In Low-Carbon Steels, Dominic Phelan, Rian Dippenaar Jan 2004

Widmanstatten Ferrite Plate Formation In Low-Carbon Steels, Dominic Phelan, Rian Dippenaar

Faculty of Engineering and Information Sciences - Papers: Part A

The mechanism by which Widmanstätten ferrite plates nucleate and grow in low-carbon steels has been studied. In-situ laser scanning confocal microscopy (LSCM) observations, optical microscopy, and electron backscattered diffraction (EBSD) techniques have been used to characterize the relationship between grain boundary allotriomorphs and Widmanstätten ferrite plates. The issue of where Widmanstätten ferrite plates nucleate is one of some debate, with theories including morphological instability and sympathetic nucleation. Evidence has been found that supports the theory of a sympathetic nucleation mechanism being responsible for the formation of Widmanstätten ferrite plates. The EBSD measurements have shown that low-angle misorientations of between 5 …


Role Of Cr And P Additions In The Development Of Microstructure And Texture In Annealed Low Carbon Steels, E V. Pereloma, I B. Timokhina, A I. Nosenkov, J J. Jonas Jan 2004

Role Of Cr And P Additions In The Development Of Microstructure And Texture In Annealed Low Carbon Steels, E V. Pereloma, I B. Timokhina, A I. Nosenkov, J J. Jonas

Faculty of Engineering and Information Sciences - Papers: Part A

The recrystallisation behaviour of four warm rolled steels was investigated during annealing. The extra-low carbon (ELC) steel displayed the highest rate of recrystallisation, the steels with additions of chromium and phosphorus (LC(Cr)), (LC(Cr,P)) recrystallised at intermediate rates, while the interstitial-free (IF) steel exhibited the lowest rate. The additions of Cr and Cr/P increased the fraction of g-fibre in the annealing textures compared to that present in the ELC steel; this effect was particularly pronounced up to 50 % recrystallisation. After the completion of recrystallisation, the steel textures were characterized by a dominant g-fibre in the IF steel, while in the …


Delta-Ferrite Recovery Structures In Low-Carbon Steels, Rian Dippenaar, Dominic Phelan Jan 2003

Delta-Ferrite Recovery Structures In Low-Carbon Steels, Rian Dippenaar, Dominic Phelan

Faculty of Engineering and Information Sciences - Papers: Part A

The development of delta-ferrite recovery substructures in low-carbon steels has been observed in-situ utilizing laser scanning confocal microscopy (LSCM). Well-developed sub-boundaries with interfacial energies much smaller than that of delta-ferrite grain boundaries formed following transformation from austenite to delta-ferrite on heating. It is proposed that transformation stresses associated with the austenite to delta-ferrite phase transformation generate dislocations that subsequently recover into sub-boundaries by a process of polygonization. Experimental evidence in support of this proposal was found in a ferritic stainless steel. Thermal cycling through the high-temperature delta-ferrite/austenite/delta-ferrite phase transformation leads to the development of a well-defined recovery substructure, which, in …


Detection Of Carbon Monoxide Within The Magellanic Bridge, E Muller, L Staveley-Smith, William Zealey Jan 2003

Detection Of Carbon Monoxide Within The Magellanic Bridge, E Muller, L Staveley-Smith, William Zealey

Faculty of Engineering and Information Sciences - Papers: Part A

The Mopra 22-m and SEST 15-m telescopes have been used to detect and partially map a region of 12CO(1-0) line emission within the Magellanic Bridge, a region lying between the Large and Small Magellanic Clouds (LMC and SMC, respectively). The emission appears to be embedded in a cloud of neutral hydrogen, and is in the vicinity of an IRAS source. The CO emission region is found to have a 60 μm/100 μm flux density ratio typical for 12CO(1-0) detections within the SMC, although it has a significantly lower 12CO brightness and velocity width. These suggest that the …