Tearing Research Papers - Academia.edu (original) (raw)
- by Boris Yakobson and +1
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- Molecular Dynamics Simulation, Fracture, Graphene, Nanotechnology
The extractive mineral model in Brazil is a direct consequence by producing drastic effects for populations living alongside mineral enterprises, water scarcity, soil and vegetation deterioration, vegetation, expropriation of land, labor... more
The extractive mineral model in Brazil is a direct consequence by producing drastic effects for populations living alongside mineral enterprises, water scarcity, soil and vegetation deterioration, vegetation, expropriation of land, labor and natural resources (CHAVEIRO, 2010). Mining has become a central theme within an artistic process, which over the course of four years has made me produce three works in partnership with artist Raoni among other collaborative partners. This dissertation is an artistic reflective process of these works: Cava (2014), Caulim (2016) and Serra (2018), this last one being a video installation made with the Pitaguary indigenous community of Monguba village, Pacatuba/CE, and also developed within the graduate research of this program. Thus, I problematize the stages of research and execution of these works from a dialogue with the image as engagement, fictional documentary and self- staging, documentary as audiovisual installation and art as the possibility of political agency.
Participation in spatial planning has specific origins rooted in the ideology that in the past was responsible for inhuman actions and large-scale social manipulations. This article is an account on participation, written in the context... more
Participation in spatial planning has specific origins rooted in the ideology that in the past was responsible for inhuman actions and large-scale social manipulations. This article is an account on participation, written in the context of over twenty years of experience in actively introducing participatory techniques into various planning procedures. The original assumptions about making spatial planning a matter of importance to local communities had to collide with the reality determined both by the authorities and by individual and collective interests. The attempt to reorient the paradigm of social participation is aimed at preserving many of its positive features.
The understanding of crack formation due to applied stress is key to predicting the ultimate mechanical behavior of many solids. Here we present experimental and theoretical studies on cracks or tears in suspended monolayer graphene... more
The understanding of crack formation due to applied stress is key to predicting the ultimate mechanical behavior of many solids. Here we present experimental and theoretical studies on cracks or tears in suspended monolayer graphene membranes. Using transmission electron microscopy, we investigate the crystallographic orientations of tears. Edges from mechanically induced ripping exhibit straight lines and are predominantly aligned in the armchair or zigzag directions of the graphene lattice. Electron-beam induced propagation of tears is also observed. Theoretical simulations account for the observed preferred tear directions, attributing the observed effect to an unusual nonmonotonic dependence of graphene edge energy on edge orientation with respect to the lattice. Furthermore, we study the behavior of tears in the vicinity of graphene grain boundaries, where tears surprisingly do not follow but cross grain boundaries. Our study provides significant insights into breakdown mechanisms of graphene in the presence of defective structures such as cracks and grain boundaries.