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   https://doi.org/10.1002/fee.2294  

   Hoellein, Timothy J; Rochman, Chelsea M (April 2021, Frontiers in Ecology and the Environment)

   Research on plastics in global ecosystems is rapidly evolving. Oceans have been the primary focus of studies to date, whereas rivers are generally considered little more than conduits of plastics to marine ecosystems. Within a watershed, however, plastics of all sizes are retained, transformed, and even extracted via freshwater use or litter cleanup. As such, plastic litter in terrestrial and freshwater ecosystems is an important but underappreciated component of global plastic pollution. To gain a holistic perspective, we developed a conceptual model that synthesizes all sources, fluxes, and fates for plastics in a watershed, including containment (ie disposed in landfill), non‐containment (ie persists as environmental pollution), mineralization, export to oceans, atmospheric interactions, and freshwater extraction. We used this model of the “plastic cycle” to illustrate which components have received the most scientific attention and to reveal overlooked pathways. Our main objective is for this framework to inform future research, offer a new perspective to adapt management across diverse waste governance scenarios, and improve global models of plastic litter. 

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2. Plastic debris in lakes and reservoirs

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   Nava, Veronica; Chandra, Sudeep; Aherne, Julian; Alfonso, María B.; Antão-Geraldes, Ana M.; Attermeyer, Katrin; Bao, Roberto; Bartrons, Mireia; Berger, Stella A.; Biernaczyk, Marcin; et al (July 2023, Nature)
3. Rules of plastic strain-induced phase transformations and nanostructure evolution under high-pressure and severe plastic flow.

   Lin, Feng; Levitas, Valery I.; Pandey, K.K.; Yesudhas, Sorb; Park, C (May 2023, arXivorg)

   Severe plastic deformations under high pressure are used to produce nanostructured materials but were studied ex-situ. We introduce rough diamond anvils to reach maximum friction equal to yield strength in shear and perform the first in-situ study of the evolution of the pressure-dependent yield strength and nanostructural parameters for severely pre-deformed Zr. ω-Zr behaves like perfectly plastic, isotropic, and strain-path-independent. This is related to reaching steady values of the crystallite size and dislocation density, which are pressure-, strain- and strain-path-independent. However, steady states for α-Zr obtained with smooth and rough anvils are different, which causes major challenge in plasticity theory. 

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4. Discrete Elasto-Plastic Rods

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5. Necking and drawing of rubber–plastic bilayer laminates

   https://doi.org/10.1039/C8SM00684A  

   Ramachandran, Rahul G.; Hariharakrishnan, S.; Fortunato, Ronald; Abramowitch, Steven D.; Maiti, Spandan; Velankar, Sachin S. (January 2018, Soft Matter)

   We examine the stretching behavior of rubber–plastic composites composed of a layer of styrene–ethylene/propylene–styrene (SEPS) rubber, bonded to a layer of linear low density polyethylene (LLDPE) plastic. Dog-bone shaped samples of rubber, plastic, and rubber–plastic bilayers with rubber : plastic thickness ratio in the range of 1.2–9 were subjected to uniaxial tension tests. The degree of inhomogeneity of deformation was quantified by digital image correlation analysis of video recordings of these tests. In tension, the SEPS layer showed homogeneous deformation, whereas the LLDPE layer showed necking followed by stable drawing owing to its elastoplastic deformation behavior and post-yield strain hardening. Bilayer laminates showed behavior intermediate between the plastic and the rubber, with the degree of necking and drawing reducing as the rubber : plastic ratio increased. A simple model was developed in which the force in the bilayer was taken as the sum of forces in the plastic and the rubber layers measured independently. By applying a mechanical energy balance to this model, the changes in bilayer necking behavior with rubber thickness could be predicted qualitatively. 

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