Tensile loading and pullouts of individual multi-walled BNNTs were studied for the first time by in-situ tests in the integrated HRTEM-AFM setup. Most important mechanical parameters, such as the ultimate tensile strength and strain, maximum sustainable load and the Young's modulus of tubes, were measured. Under parallel HRTEM observations the measured mechanical parameters were correlated to experimental conditions and tube structures.
A number of applications have been proposed concerning the isomers, including the creation of a gamma-ray laser, since some of them may store large amounts of energy for long times. Against this background, the field of triggered gamma emission is entering a new phase in which improved level data allow targeting of specific potentially-useful transitions. In the present work, the configuration-constrained (diabatic blocking) calculations, with inclusion of γ-deformation, are performed to study the multi quasi-particle (multi-qp) excitations of 178Hf. The detailed excitation energies known in 178Hf are reasonably reproduced. From our calculations, two levels besides the existing level at 2.573 MeV are found for candidates of these intermediate states (or called depletion levels). Whether these two excited states actually exist will require additional experimentation.
We report here a method for measurement of thermoelectric power of quasi-one dimensional nano-materials with a simple platform, where individual nanomaterial is assembled with nano-probes in a scanning electron microscope. This approach allows repeated manipulation and thermoelectric measurement of the same loaded nanosample with adjustable number of individual nanotubes or nanowires. It also allows assembly of multiple samples on one measurement stage. For multi-walled carbon nanotube bundles, we have observed a weak trend that, when the number of individual tubes in a bundle varies from ten millions to around a hundred thousand, the thermoelectric power almost remains at around 10 mu V/K. When the tube number in the bundle is further reduced, the up-limit of the thermoelectric power gradually increases to a value near 20 mu V/K.