Elasticity and nanomechanical response of Aspergillus niger spores using atomic force microscopy.

The elasticity and nanomechanical response of Aspergillus niger spores determined using atomic force microscopy (AFM) and nanoindentation are discussed. The force-displacement curve of the spore surfaces shows that the average surface roughness of spores was approximately 33 nm and that the adhesion force ranged from 9 to 28 nN. The Young's modulus of the A. niger spores ranged from 0.1 to 21.4 GPa and the hardness ranged from 0.01 to 0.17 GPa. The critical buckling load of the spore membrane is 290 µN.

Thermomechanical properties of polymer nanolithography using atomic force microscopy.

The temperature-dependent mechanical properties of polyethylene terephthalate (PET) polymers are investigated using force-distance curves, adhesion force, and atomic force microscope (AFM) nanolithography combined the heating techniques. The results show that the width of grooves on the polymers at 20-60 °C were in the range of 14-363 nm. The wear depth of the polymers increased with increasing heating temperature. A volume of 251.85-2422.66 µm(3) at a load of 30-50 nN with heating to 30-60 °C was removed, as compared to that of 26.60-70.30 µm(3) obtained at room temperature. The contact forces of PET started increasing at 9 nN, whereas the size of the holes was average at a pressure. The results may be of importance in explaining the heating relationship among adhesion force, volume removal rate, and pressure.

Electromechanical characteristics of ZnO:Al nanorods.

In this study, we explore the effect of aluminum doping on the mechanical, piezoelectric, and semiconductive properties of zinc oxide (ZnO) nanorods using scanning probe microscopy. The results show that the size of ZnO:Al nanorods can be changed by tuning the dopant concentrations during nanorod growth. The average surface potentials of the samples were -42.2-34.4 mV. Single nanorod bending generation output surface potentials were 0.05-0.08 V. The power density per unit substrate area was 0.72 nW/mm(-2) for a device outputting ultrasonic wavelengths.

Nanoindentation characteristics of clamped freestanding Cu membranes.

This research employed instrumented nanoindentation to address the issue of bending to stretching-induced deformation of clamped freestanding Cu membranes. The experimental results show that indentation-induced plastic deformation only comes into effect at the centre and the indented edge of the Cu membrane when the indenter is applied, while the other locations remain undamaged. A step-by-step evolution was presumed for the time histories of the bending to stretching-induced deformation and for the timing of the significant change in slope of the load-deflection curve. Deformation was deliberately introduced at the transition from the single-point bending indentation to the surface stretching indentation at the impact location touched with the indenter. Good elastic recovery was found at locations away from the indenter. A similar finding can be arrived at by means of finite element analysis.