Dry adhesives from carbon nanofibers grown in an open ethanol flame

Based on magnetic-field-assisted growth of carbon nanofibers in an open ethanol flame we fabricated arrays of carbon nanofibers with different degrees of orientation. Inspired by the dry adhesive system of geckos we investigated the adhesive properties of such carbon nanofiber arrays with ordered and random orientation. AFM-based force spectroscopy revealed that adhesion force and energy rise linear with preload force. Carbon nanofibers oriented by a magnetic field show a 68% higher adhesion (0.66 N/cm2) than the randomly oriented fibers. Endurance tests revealed that the carbon nanofiber arrays withstand 50.000 attachment/detachment cycles without observable wear.

Experimental Study on the Atomization and Chemiluminescence Characteristics of Ethanol Flame

The breakup regime in ethanol diffusion flame under different conditions was studied by the high speed camera system combined with the UV camera system. Spray angle and Weber number (We) were used to represent the change of breakup regime. With the increases of spray angle and We, the breakup mode changes from the Rayleigh-type breakup regime to the superpulsating regime. The reaction area and intensity of ethanol flames under different breakup regimes could be discussed by theOH⁎distribution. From Rayleigh-type breakup regime to superpulsating breakup regime, theOH⁎distribution increased and the oxidation-reduction reaction area expanded. At the condition of superpulsating breakup mode, the intensity ofOH⁎was significantly higher than that of other modes. The flame luminous length can be obtained by theOH⁎emission, andOH⁎distribution reflects the structure of flame. When the breakup regime changes from the fiber-type breakup regime to the superpulsating regime, the flame luminous length increases suddenly.