Publications by authors named "R Setnescu"

Electrical properties and electro-thermal behavior were studied in composites with carbon black (CB) or hybrid filler (CB and graphite) and a matrix of linear low-density polyethylene (LLDPE). LLDPE, a (co)polymer with low crystallinity but with high structural regularity, was less studied for (PTC) applications, but it would be of interest due to its higher flexibility as compared to HDPE. Structural characterization by scanning electron microscopy (SEM) confirmed a segregated structure resulted from preparation by solid state powder mixing followed by hot molding.

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Article Synopsis
  • A novel conductive composite made from a mix of HDPE and LLDPE with carbon black and graphite demonstrated comparable or superior electrical properties compared to a traditional HDPE composite with similar fillers, despite having a lower overall concentration of conductive material.
  • Testing showed that the new composite had better performance during thermal cycling, exhibiting less resistance increase and diminished negative temperature coefficient (NTC) effects, especially when radiation crosslinking was applied.
  • The physical mixing method used for creating this composite was found to be more effective in achieving lower resistivity in solid state and enhancing positive temperature coefficient (PTC) effects, suggesting that future research should focus on optimizing the preparation techniques and material properties.
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The durability of polymeric materials is closely linked to their degradation under specific operating conditions when different stressors-general or specific, such as high temperature, sunlight or ionizing radiation, solvents, or mechanical stresses-act simultaneously, causing degradation. In the case of electrical cables, the durability of the electrically insulating materials used in their construction is an important parameter to ensure their operational security. In this work, we studied the degradation state of various types of electrical insulating materials from cables used in particle acceleration systems under European Organization for Nuclear Research (CERN) conditions (e.

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The use of nanotechnologies in the applied biomedical sciences can offer a new way to treat infections and disinfect surfaces, materials, and products contaminated with various types of viruses, bacteria, and fungi. The Cu-Au nanoparticles (NPs) were obtained by an eco-friendly method that allowed the obtaining in a one-step process of size controlled, well dispersed, fully reduced, highly stable NPs at very mild conditions, using high energy ionizing radiations. The gamma irradiation was performed in an aqueous system of Cu/Au/Sodium Dodecyl Sulfate (SDS)/Ethylene Glycol.

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Due to the presence of efflorescences and improper microclimate conditions for conservation, pink-pigmented areas were reported in two historic monuments in Northern and Central part of Romania. The aims of the present study were to find the nature of pink pigments observed on the pictorial layer, original and infilling mortar, to investigate the presence of carotenoids both on mural paintings and in the isolated halophilic bacterial strains and to preliminary characterize and identify the producing strains. Their role in the aesthetical biodeterioration of historic monuments was also pointed out.

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