This paper describes the fabrication of large arrays (10(6) units in 1 cm(2)) of 100 µm tall, single-crystal silicon columns with submicron tip cross-sections. The columns are formed using thin film deposition and growth, reactive ion etching, and deep reactive ion etching. The columns can be either slightly tapered or have pencil-like morphology with nanoscaled tip diameter (41 nm). Conformal ...

Knowledge of the fate and transport of functionalized carbon nanotubes (CNTs) in porous media is crucial to understand their environmental impacts. In this study, laboratory column and modeling experiments were conducted to mechanistically compare the retention and transport of two types of functionalized CNTs (i.e., single-walled nanotubes and multi-walled nanotubes) in acid-cleaned, baked, an...

The results of several perforated steel thin-walled U-shaped sections subject to compression are presented. The ultimate strength obtained from experimental tests is compared to the one obtained from numerical simulation by finite element method. The experimental tests were carried out according to the standard 10.2.02 of the FEM. The meshing, loading, boundary conditions for supports, geometri...

The increased production and commercial use of nanomaterials combined with a lack of regulation to govern their disposal may result in their introduction to soils and ultimately into groundwater systems. In this study, we investigated the transport behavior of carboxyl-functionalized single-walled carbon nanotubes (SWNTs) in columns packed with a natural soil. In general, SWNT deposition (filtr...

UltraSTEEL material has been reported to have higher yield and ultimate strengths than plain mild steel under quasi-static loads. This project aims to study the energy absorption characteristics of UltraSTEEL thin-walled structures when subjected to axial impact loads. The numerical modelling starts from duplicating the UltraSTEEL dimpling process and defining the resultant material properties ...

This paper studies the post-local buckling behaviour of steel plates in concrete-filled thin-walled steel tubular columns under biaxial loading using the finite element method. Geometric and material nonlinear finite element analyses are undertaken to investigate the post-local buckling strengths of imperfect steel plates under stress gradients. Based on the results obtained from the nonlinear ...