Search results for " plastic"
showing 10 items of 3463 documents
Environmental factors modulating cold tolerance, gene expression and metabolism in Drosophila montana
2011
Eco-physiological aspects of adaptation to seasonal environments : the latitudinal range expansion of the Colorado potato beetle across Europe
2013
Structure and dielectric breakdown strength of nano calcium carbonate/polypropylene composites
2013
Nanodielectrics, a 21st-century phenomena, is envisioned to be the answer for material challenges in progressive high-voltage technology. It is well known that the proper dispersion of nanoparticles plays a key role in improving the dielectric properties of a material, but to understand where changes in the properties of a material originate, it is also essential to reveal the multiscale structure of the material. In this study, the dielectric permittivity, breakdown strength, and structure of nano calcium carbonate (nano-CaCO3)/polypropylene composites with 1.8-8.1 wt % doping were characterized systematically. The combined results from transmission electron microscopy, Raman microscopy, a…
Coopetition, standardization and general purpose technologies : A framework and an application
2023
Funding Information: We thank Paul Wiegmann, Geerten van de Kaa, Filippo Grillo, Tuomo Uotila, Elina Berghäll, Joakim Wikström and a number of anonymous reviewers for helpful comments. Earlier versions of the paper have been presented at EURAS2022 conference at Adam Smith Business School of the University of Glasgow, 38th Summer Seminar of Finnish Economist at University of Jyväskylä and Lappeenranta-Lahti University of Technology LUT. Heikkilä gratefully acknowledges financial support from the Foundation for Economic Education (Liikesivistysrahasto, Reino Rossi Memorial Fund), PHP Säätiö and the Jyväskylä University School of Business and Economics. We argue that coopetition and standardiz…
Divu diazepāma devu ietekme uz Alcheimera slimības modeļa dzīvnieku sinaptisko plasticitāti un acetilholīna šķelšanu
2018
Šī darba mērķis bija noteikt gamma-aminosviestskābes (GABA) receptora benzodiazepīna saita agonista diazepāma (DZP) ļoti zemas (0,05 mg/kg) un vidējās (1 mg/kg) devas efektus uz Alcheimera slimības (AD) modeļa žurku sinaptisko plasticitāti un acetilholīna šķelšanu. Rezultāti rāda, ka AD modeļa žurku smadzenēs tika būtiski samazināta sinaptofizīna-1 (SYP) ekspresija un būtiski pieauga acetilholīna šķelšanās. Ļoti zema (0,05 mg/kg) diazepāma deva spēja uzlabot sinaptisko plasticitāti, savukārt abas (0,05 mg/kg un 1 mg/kg) diazepāma devas būtiski normalizēja acetilholīna šķelšanos AD modeļa žurku garozā un hipokampā. Iegūtie dati norāda uz ļoti zemas un vidējas devas diazepāma neiroprotektīvo …
Improved camouflage through ontogenetic colour change confers reduced detection risk in shore crabs
2019
Abstract Animals from many taxa, from snakes and crabs to caterpillars and lobsters, change appearance with age, but the reasons why this occurs are rarely tested.We show the importance that ontogenetic changes in coloration have on the camouflage of the green shore crabs (Carcinus maenas), known for their remarkable phenotypic variation and plasticity in colour and pattern.In controlled conditions, we reared juvenile crabs of two shades, pale or dark, on two background types simulating different habitats for 10 weeks.In contrast to expectations for reversible colour change, crabs did not tune their background match to specific microhabitats, but instead, and regardless of treatment, all de…
A Green Approach for Recycling Compact Discs
2023
Compact discs (CDs) and digital versatile discs (DVDs) are mainly made by polycarbonate disc, a thin layer of aluminum or silver, a thin layer of a coating and a thin layer of a label of paper or PET. The recycling of these discs is difficult due to the removal of these non-polymeric layers and to our best knowledge, no industrial plants have been resent for their recycling. In this work, we propose a facile way to remove the non-polymeric layers and investigate the effect of the repetitive extrusion process on the processability and on the mechanical properties of the recycled polycarbonate. A few works have been published dealing with both the removal of the non-polymeric layers and the m…
Protein levels of brain-derived neurotrophic factor in the hippocampus of low/high aerobic capacity rats
2010
Hippocrates and Plato have first documented the connection between a healthy mind and body, during a period which launched analytical thinking and philosophy in Ancient Greece. Modern research has also indicated the contribution of an active lifestyle to enhanced brain performance and decreased incidence of neurodegenerative diseases and mood disorders such as Alzheimer’s disease and depression respectively. This has been hypothesized to emerge through mechanisms which are enhanced by exercise and contribute on brain plas-ticity and health. The Neurotrophins hypothesis implicates several molecules in brain plasticity and healthy aging. Among them, Brain-derived Neurotrophic Factor (BDNF) ha…
A Quantitative Analysis of the Thermoelastic Effect in CFRP Composite Materials
2010
In this study the thermoelastic signal from carbon fibre-reinforced plastic (CFRP) laminates is investigated. A comparison between the theoretical and experimental values of the thermoelastic signal is reported, with the theoretical predictions obtained from two different quantitative models. These models are based on the classic thermoelastic effect law extended to the case of orthotropic materials (by using the mesomechanical or bulk approach), and the modified law assuming that the surface resin-rich layer behaves as a strain witness of the laminate. It is found that the theoretical predictions of the two models can be strongly and differently influenced by the intrinsic orthotropy of ca…
New Insights into Segmental Packing, Chain Dynamics and Thermomechanical Performance of Aliphatic Polyurea Composites: Comparison between Silica Oxid…
2021
Polyurea (PU) is intrinsically reinforced by its microphase-separated morphology, giving its excellent mechanical properties. In this study, it is shown how a high-index PU formulation applies easy diffusion of hard segments into the soft phase of the PU matrix and tune its chain mobility. Moreover, the interaction of micro (>100 nm), nano (<100 nm) fillers with the microdomains and their thermomechanical properties are unraveled. Herein, nanosilica oxide (NS) and micro titanium (III) oxide (Ti2O3) are incorporated at low loadings into a solvent-free two-component aliphatic PU via insitu polymerization. While NS achieves an interfacial interaction with urea groups and forms a tight ha…