ABSTRACT
From an environmental and cost-effective perspective, a number of research challenges can be found for electronics, household, but especially in the automotive polymer parts industry. Reducing synthesis steps, parts coating and painting, or other solvent-assisted processes, have been identified as major constrains for the existing technologies. Therefore, simple polymer processing routes (mixing, extrusion, injection moulding) were used for obtaining PMMA/HNT nanocomposites. By these techniques, an automotive-grade polymethylmethacrylate (PMMA) was modified with halloysite nanotubes (HNT) and an eco-friendly additive N,N'-ethylenebis(stearamide) (EBS) to improve nanomechanical properties involved in scratch resistance, mechanical properties (balance between tensile strength and impact resistance) without diminishing other properties. The relationship between morphological/structural (XRD, TEM, FTIR) and tribological (friction) properties of PMMA nanocomposites were investigated. A synergistic effect was found between HNT and EBS in the PMMA matrix. The synergy was attained by the phase distribution resulted from the selective interaction between partners and favourable processing conditions. Modification of HNT with EBS improved the dispersion of nanoparticles in the polymer matrix by increasing their interfacial compatibility through hydrogen bonding established by amide groups with aluminol groups. The increased interfacial adhesion further improved the nanocomposite scratch resistance. The PMMA/HNT-EBS nanocomposite had a lower coefficient of friction and lower scratch penetration depth than PMMA/HNT nanocomposite.
ABSTRACT
Security diagnostics expose vulnerabilities and privacy threats that exist in commercial Intelligent Virtual Assistants (IVA) - diagnostics offer the possibility of securer IVA ecosystems.
ABSTRACT
Organizations often struggle to capture the necessary functional capabilities for each cloud-based solution adopted for their information systems. Identifying, defining, selecting, and prioritizing these functional capabilities and the security components that implement and enforce them is surprisingly challenging. This article explains recent developments by the National Institute of Standards and Technology (NIST) in addressing these challenges. The article focuses on the capability oriented methodology for orchestrating a secure cloud ecosystem proposed as part of the NIST Cloud Computing Security Reference Architecture. The methodology recognizes that risk may vary for cloud Actors within a single ecosystem, so it takes a risk-based approach to functional capabilities. The result is an assessment of which cloud Actor is responsible for implementing each security component and how implementation should be prioritized. A cloud Actor, especially a cloud Consumer, that follows the methodology can more easily make well-informed decisions regarding their cloud ecosystems.
