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Faculty of Science - Papers (Archive)

Carbon

Articles 31 - 35 of 35

Full-Text Articles in Physical Sciences and Mathematics

Photocatalytic Oxidation Of Methanol Using Titanium Dioxide/Single-Walled Carbon Nanotube Composite, Jun Chen, Carol M. Lynam, Chonlada Dechakiatkrai, Gordon G. Wallace, Sukon Phanichphant Jan 2007

Photocatalytic Oxidation Of Methanol Using Titanium Dioxide/Single-Walled Carbon Nanotube Composite, Jun Chen, Carol M. Lynam, Chonlada Dechakiatkrai, Gordon G. Wallace, Sukon Phanichphant

Faculty of Science - Papers (Archive)

Titanium dioxide/single-walled carbon nanotube TiO2/SWNT composites were prepared for photocatalytic applications. Thecomposites were characterized using UV-visible and Raman spectroscopy, zeta-potential measurements, cyclic voltammetrycoupled with a photoreactor, scanning electron microscopy, and transmission electron microscopy coupled with energy dispersiveX-ray spectroscopy. The photocatalytic activity of TiO2 and the TiO2/SWNT composite was investigated using the photo-oxidationof methanol in sulfuric acid as supporting electrolyte. The results indicate that the TiO2/SWNT composite enhances the photocatalyticactivity compared to TiO2 alone. Electrochemical studies of the TiO2/SWNT composite were also carried out in varioussupporting electrolytes and the presence of SWNTs was shown to increase the current achieved in voltammetric …


Annual Variation Of Strato-Mesospheric Carbon Monoxide Measured By Ground-Based Fourier Transform Infrared Spectrometry, Voltaire A. Velazco, S.J. Wood, M Sinnhuber, I Kramer, Nicholas B. Jones, Y Kasai, Justus Notholt, Thorsten Warneke, T Blumenstock, F Hase, F Murcray, O Schrems Jan 2007

Annual Variation Of Strato-Mesospheric Carbon Monoxide Measured By Ground-Based Fourier Transform Infrared Spectrometry, Voltaire A. Velazco, S.J. Wood, M Sinnhuber, I Kramer, Nicholas B. Jones, Y Kasai, Justus Notholt, Thorsten Warneke, T Blumenstock, F Hase, F Murcray, O Schrems

Faculty of Science - Papers (Archive)

We present long-term time-series of strato-mesospheric CO vertical columns measured from stations located in Antarctica, mid-latitudes and the Arctic, covering the period from 19972005. The instrument and the measurement technique allows the separation of tropospheric and strato-mesospheric contributions to the CO column, therefore providing information on the chemistry and dynamics both at low and high altitudes. Data from polar stations show a similar annual variability of strato-mesospheric CO with a strong maximum in late winter and spring. A small enhancement in late summer for some stations, which we call the "summer bulge", can be seen occasionally. Generally, the mid-latitude stations …


The Loss Of Carbon Dioxide From Activated Perbenzoate Anions In The Gas Phase: Unimolecular Rearrangement Via Epoxidation Of The Benzene Ring, David G. Harman, Aravind Ramachandran, Michelle Gracanin, Stephen J. Blanksby Jan 2006

The Loss Of Carbon Dioxide From Activated Perbenzoate Anions In The Gas Phase: Unimolecular Rearrangement Via Epoxidation Of The Benzene Ring, David G. Harman, Aravind Ramachandran, Michelle Gracanin, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

The unimolecular reactivities of a range of perbenzoate anions (X−C6H5CO3-), including the perbenzoate anion itself (X = H), nitroperbenzoates (X = para-, meta-, ortho-NO2), and methoxyperbenzoates (X = para-, meta-OCH3) were investigated in the gas phase by electrospray ionization tandem mass spectrometry. The collision-induced dissociation mass spectra of these compounds reveal product ions consistent with a major loss of carbon dioxide requiring unimolecular rearrangement of the perbenzoate anion prior to fragmentation. Isotopic labeling of the perbenzoate anion supports rearrangement via an initial nucleophilic aromatic …


Carbon Nanotubes: Enhancing The Polymer Building Blocks For Intelligent Materials, Marc In Het Panhuis Jan 2006

Carbon Nanotubes: Enhancing The Polymer Building Blocks For Intelligent Materials, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

Electroactive polymers can be engineered at the molecular level to recognise external stimuli, they are conductive and they are capable of localised processing. These are properties which make them ideal building blocks for intelligent materials. This article investigates the suitability of carbon nanotubes of enhancing (polymer) building blocks for intelligent materials.


Increased Northern Hemispheric Carbon Monoxide Burden In The Troposphere In 2002 And 2003 Detected From The Ground And From Space, L N. Yurganov, P Duchatelet, A V. Dzhola, D P. Edwards, F Hase, I Kramer, E Mahieu, J Mellqvist, J Notholt, P C. Novelli, A Rockmann, H E. Scheel, M Schneider, A Schulz, A Strandberg, R Sussmann, H Tanimoto, Voltaire A. Velazco, J Drummond, J Gille Jan 2005

Increased Northern Hemispheric Carbon Monoxide Burden In The Troposphere In 2002 And 2003 Detected From The Ground And From Space, L N. Yurganov, P Duchatelet, A V. Dzhola, D P. Edwards, F Hase, I Kramer, E Mahieu, J Mellqvist, J Notholt, P C. Novelli, A Rockmann, H E. Scheel, M Schneider, A Schulz, A Strandberg, R Sussmann, H Tanimoto, Voltaire A. Velazco, J Drummond, J Gille

Faculty of Science - Papers (Archive)

Carbon monoxide total column amounts in the atmosphere have been measured in the High Northern Hemisphere (30°- 90° N, HNH) between January 2002 and December 2003 using infrared spectrometers of high and moderate resolution and the Sun as a light source. They were compared to ground-level CO mixing ratios and to total column amounts measured from space by the Terra/MOPITT instrument. All these data reveal increased CO abundances in 2002-2003 in comparison to the unperturbed 2000-2001 period. Maximum anomalies were observed in September 2002 and August 2003. Using a simple two-box model, the corresponding annual CO emission anomalies (referenced to …