Hierarchical zeolite monoliths with multimodal porosity are of paramount importance as they open up new horizons for advanced applications. So far, hierarchical zeolites based on nanotube scaffolds have never been reported. Inspired by the organization of biominerals, we have developed a novel precursor scaffolding-solid phase crystallization strategy for hierarchical zeolites with a unique nan...

TiO2 nanotube arrays on the surface of dental implants were fabricated by two-step anodic oxidation. Their effects on bone-implant contact were researched by a pilot in vivo study. The implants were classified into four groups. An implant group with TiO2 nanotube arrays and recombinant human bone morphogenetic protein-2 (rhBMP-2) was compared with various surface implants, including machined su...

In this work surface-enhanced resonance Raman spectroscopic experiments have demonstrated that metallic single-walled carbon nanotubes can be used as chemical assemblies between the pyrene analyte and the silver colloidal surface. Pyrene has been detected at concentrations lower than 10(-9) M by use of the 514.5 nm excitation laser line. A charge transfer from the surface to the nanotube charac...

A model is proposed for two observed current–voltage (I – V) patterns in a recent experiment with a scanning tunneling microscope tip and a carbon nanotube @Collins et al., Science 278, 100 ~1997!#. We claim that there are two mechanical contact modes for a tip ~metal!–nanotube ~semiconductor! junction ~1! with or ~2! without a tiny vacuum gap ~0.1–0.2 nm!. With the tip grounded, the tunneling ...

Carbon nanotube transistors combine molecular-scale dimensions with excellent electronic properties, offering unique opportunities for chemical and biological sensing. Here, we form supported lipid bilayers over single-walled carbon nanotube transistors. We first study the physical properties of the nanotube/supported lipid bilayer structure using fluorescence techniques. Whereas lipid molecule...

In this paper, we applied self-aligned T-gate design to aligned carbon nanotube array transistors and achieved an extrinsic current-gain cutoff frequency (ft) of 25 GHz, which is the best on-chip performance for nanotube radio frequency (RF) transistors reported to date. Meanwhile, an intrinsic current-gain cutoff frequency up to 102 GHz is obtained, comparable to the best value reported for na...

The elastic moduli of polymer-carbon nanotube composites are examined by molecular dynamics simulations of a single-walled carbon nanotube embedded in polyethylene. The overall system is modeled with a many-body bond order potential due to Brenner. Alternatively, only the carbon nanotube is modeled with Brenner’s potential and the polyethylene matrix is modeled by a united-atom potential. For t...

We study the geometry-dependent resistivity scaling in single-walled carbon nanotube films as a function of nanotube and device parameters using Monte Carlo simulations. We first demonstrate that these simulations can model and fit recent experimental results on the scaling of nanotube film resistivity with device width. Furthermore, we systematically study the effect of four parameters; namely...

The use of carbon nanotubes for field effect nanoelectronic devices, which has been recently demonstrated, motivates further studies of electrochemical and chemical analogues of nanotube molecular transistors. However, chemical gating is not applicable for modern electronics due to its slow response. Herein we propose a novel molecular electronic device: Nanotube LightControlled Switch (NLCS). ...

We have investigated conditions for making nanoindents on a polycarbonate using a carbon nanotube tip in terms of structural stability of the nanotube tip. Even under a weak force of ∼ 50 nN acting in the axial direction to the nanotube, the indents with mean depth of 3.91 nm were successfully realized on the polycarbonate in air at room temperature. In this case, there were no structural chang...