Multi-walled carbon nanotubes were synthesized on a Ni/Au/Ti substrate using a thermal chemical vapor deposition process. A Ni layer was used as a catalyst, and an Au layer was applied as a barrier in order to prevent diffusion between Ni and Ti within the substrate during the growth of carbon nanotubes. The results showed that vertically aligned multi-walled carbon nanotubes could be uniformly...

The formation of carbon nanotubes (CNTs) through precipitated carbons emerging from supersaturated metal catalysts is an established mechanism for their growth during the CVD process. Here, the CNT growth mode is determined by the interaction between the substrate and the catalyst nanoparticle, e.g., the tip-growth mode for the weak adhesion between them and the base-growth mode for the strong ...

R. Czerw, B. Foley, D. Tekleab, A. Rubio, P. M. Ajayan, and D. L. Carroll School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634 Department of Physics, Trinity College Dublin, Dublin 2, Ireland Departamento de Fisica de Materiales, UPV/EHU, Donostia International Physics Center (DIPC), Centro Mixto CSIC-UPV/EHU, 20018 San Sebastian, Spain Department of Ma...

Temporal dynamics and vertical patterns in bacterial abundances and activities were studied in a shallow subtidal sand flat in the Sylt-Rømø Basin (North Frisian Wadden Sea, Germany.) Extracellular enzymatic activities, bacterial carbon production and community respiration showed strong (factor of 4–5) temporal variations that 5 were mostly related to seasonal temperature change, but also to ch...

Aligned carbon nanotubes have been grown using microwave plasma enhanced chemical vapor deposition (PECVD). The carbon nanotubes are nucleated from iron catalyst particles which, during growth, remain adherent to the silicon substrates. By analysis with high-resolution electron microscopy, we observe iron silicide roots penetrating into the silicon substrate at the interface of the catalyst par...

This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H2 were compa...

This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H2 were compa...

Garlic mustard (Alliaria petiolata, Brassicaceae) is an invasive, nonindigenous species currently invading the understory of North American woodlands where it is a serious threat to the native flora. Part of this success might be due to allelopathic interference by garlic mustard. Two congeneric species, the European Geum urbanum and the North American Geum laciniatum, were tested for allelopat...

Vertically aligned single-walled carbon nanotubes (VA-SWNTs) have been synthesized by an Alactivated plasma-enhanced chemical vapor deposition (PECVD) method. On this basis, we have developed a facile but effective method for direct growth of multicomponent micropatterns of VA-SWNTs interposed within the patterned areas surrounded by vertically aligned multi-walled carbon nanotubes (VA-MWNTs) o...