Biomedical subjects

A Kutana

Publications and source records attributed to A Kutana.

3 recordsLinked to original sources

PubMed2006

Atomistic simulations of electrowetting in carbon nanotubes.

Electrowetting of carbon nanotubes by mercury was studied using classical molecular dynamics simulations in conjunction with a macroscopic electrocapillarity model. A scaled ab initio mercury dimer potential, optimized to reproduce the mercury liquid density (at 300 K), melting point, and wetting angle on graphite, was selected for the simulations. Wetting of (20,20) single-walled carbon nanotubes by mercury occurs above a threshold voltage of 2.5 V applied across the interface. Both the electrocapillary pressure and imbibition velocity increase quadratically with voltage and can acquire large values, for example, 2.4 kbar and 28 m/s at 4 V, indicating a notable driving force. The observed voltage scaling can be captured by the Lucas-Washburn equation modified to include a wetting-line friction term.

Capillary Action↗

PubMed2006

Amplitude response of single-wall carbon nanotube probes during tapping mode atomic force microscopy: Modeling and experiment.

Imaging of surfaces with carbon nanotube probes in tapping mode results frequently in complex behavior in the amplitude-distance curves monitored. Using molecular mechanics simulations, we calculate the force exerted on a nanotube pressed against a smooth surface as it undergoes deformation and buckling. This nonlinear force is then used in a macroscopic equation, describing the response of a damped harmonic oscillator, to predict the amplitude response of a nanotube AFM probe. Similarities between the prediction and experiment suggest that the complex amplitude response seen in the experiment may be explained by the nonlinearity in the force exerted on the nanotube and thus must not necessarily be related to the structure of the surface.

Computer Simulation↗

PubMed2005

Electrowetting in carbon nanotubes.

We demonstrate reversible wetting and filling of open single-wall carbon nanotubes with mercury by means of electrocapillary pressure originating from the application of a potential across an individual nanotube in contact with a mercury drop. Wetting improves the conductance in both metallic and semiconducting nanotube probes by decreasing contact resistance and forming a mercury nanowire inside the nanotube. Molecular dynamics simulations corroborate the electrocapillarity-driven filling process and provide estimates for the imbibition speed and electrocapillary pressure.

Journal Article↗