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Purely mechanically induced mass transport between diamond and transition metals are investigated using transition thin metal film-deposited AFM tip scratching and in situ TEM scratching test. Due to the weak strength of the transition metal-diamond joints and transition metal thin films, AFM scratching rarely activated the mass transport interaction at the diamond-transition metal thin film interfaces. In situ TEM scratching tests were performed by using a Nanofactory STM holder. The interaction at diamond and tungsten interface was successfully activated by nanoscale in-situ scratching under room temperature. The lattice structure of diamond and tungsten were characterized by HRTEM. The stress to activate the interaction was estimated by measuring the interplanar spacing change of tungsten nanotips before scratching and at the frame that the interaction was activated., Comment: 28 Pages, 10 Figures

Liquid Crystalline Elastomers (LCEs) are active materials that are of interest due to their programmable response to various external stimuli such as light and heat. When exposed to these stimuli, the anisotropy in the response of the material is governed by the nematic director, which is a continuum parameter that is defined as the average local orientation of the mesogens in the liquid crystal phase. This nematic director can be programmed to be heterogeneous in space, creating a vast design space that is useful for applications ranging from artificial ligaments to deployable structures to self-assembling mechanisms. Even when specialized to long and thin strips of LCEs -- the focus of this work -- the vast design space has required the use of numerical simulations to aid in experimental discovery. To mitigate the computational expense of full 3-d numerical simulations, several dimensionally-reduced rod and ribbon models have been developed for LCE strips, but these have not accounted for the possibility of initial transverse curvature, like carpenter's tape spring. Motivated by recent experiments showing that transversely-curved LCE strips display a rich variety of configurations, this work derives a dimensionally-reduced 1-d model for pre-curved LCE strips. The 1-d model is validated against full 3-d finite element calculations, and it is also shown to capture experimental observations, including tape-spring-like localizations, in activated LCE strips.