Physical and mechanical investigation for polyionic liquid/poly(vinyl alcohol) blends

Purpose This study aims to polymerize of 1-butyl-3-vinylimidazolium bromide (PIL). PIL was embedded into PVA with a different content ratio by casting method. This research also deals with the effect of adding PIL in different proportions to PVA on the electrical and mechanical properties properties in addition to the morphology of the prepared samples. Design/methodology/approach 1-Butyl-3-vinylimidazolium bromide was synthesized through quaternization and free radical polymerization. The resulting polymer was characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis and differential scanning calorimetry. In addition to the morphology of PVA, PVA/PIL was investigated by polarizing microscope. Also, the effect of PIL content on the electrical and mechanical properties was evaluated. Findings The findings of this study might lead to new applications for PVA and PILs in electrical and dielectrics. The mechanical results revealed that the tensile strength increased slightly with increasing polyionic liquid (PIL) content and decreased above 10% PIL. While the elongation at break increased significantly with increasing PIL content and begin to decrease above 10% PIL. Also, the electrical property of the poly(vinyl alcohol) (PVA)/PIL blends was improved because of the strong plasticizing effect of PIL. Also, the electrical conductivity of these polymer electrolytes is greatly increased. This indicates that the imidazolium-based PIL has an effective approach that leads to an increase in the conductivity of the polymer. The PILs/PVA design will not only enrich the chemical structure but also will contribute to green manufacturing techniques and a processing methodology that enables green membrane manufacture. Originality/value This study contributes to green manufacturing techniques and a processing methodology that enables “green” membrane manufacture.

Experimental investigation of the dynamics of a slider-crank mechanism with local linear force input

Conventional implementation of slider-crank mechanisms result in high loads transmitted through the mechanical structure, inhibiting the design of compact and oil-free machines. Therefore, this research proposes to step away from the conventional, i.e. rotative, actuation and to investigate local linear actuation on the slider-component directly, while maintaining the kinematic link of the slider-crank configuration. In this work the local linear actuating principle is evaluated experimentally where the goal is to obtain a continuous movement of the slider mechanism where Top Dead Centre & Bottom Dead Centre are reached and to minimise the loads transmitted through the mechanical structure. The non-isochronous transient behaviour of a slider-crank mechanism loaded with a spring-damper element is detailed as well as the optimal working conditions at steady state to achieve a reduced loading of the kinematic structure. By matching the operating frequency and resonance frequency of the system, a reduction of the loads transmitted through the system by 63% of the nominal spring load can be achieved. Further experimental (and multibody mechanical) investigation on the influence of flywheel exposes a clear trade-off between the sensitivity of the system and the transmission of the actuation force through the kinematic link.

Experimental and Quantum Mechanical Investigation of N-heterocyclic Carbene Palladium Complex: Synthesis and Antibacterial Activity

In this study, we report the synthesis, characterization, and biological activity of Pd-NHC-PEPPSI complex 2a. Further confirmations of structural details were provided by a single-crystal X-ray. A single crystal of 2a shows that the coordination geometry around Pd slightly distorted square-planar geometry. Intermolecular interactions have been studied through the NBO analyses. Structural parameters and spectroscopic properties of the complexes are well interpreted by DFT and TD-DFT calculations. Moreover, the complex 2a showed a remarkable antimicrobial effect against Micrococcus luteus LB 14110mm, Listeria monocytogenes ATCC 19117, Salmonella typhimurium ATCC 14028, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa, and Candida albicans.

Fracture Mechanical Analysis of Gleeble Simulated Heat Affected Zones in High Strength Steels

During the research work the fracture mechanical investigation of heat affected zones of thermomechanical rolled high strength steels (Voestalpine Alform 960M) were carried out. For production of appropriate heat affected zones Gleeble 3500 physical simulator was applied, with different heating cycles and specific cooling times. Following the simulation, fracture mechanical investigations were performed, in favor of determination crack tip opening displacement (CTOD or δ) values.

Petrographic and Physical-Mechanical Investigation of Natural Aggregates for Concrete Mixtures

The availability of different lithology with which concrete can be packaged could create substantial questions on the differences that they can provide to the same mixture. Different kinds of aggregates were analyzed individually to investigate their main characteristics, which allowed us to package five types of concrete mixtures. These five mixtures were compared to each other through compressive strength values. Furthermore, it was considered microscopically what possible differences could exist between these different mixtures, for example, differences in the cement/aggregate reaction. The chemical characterization of the aggregates, used as the skeleton of the cement mixes, was proposed as an important investigative phase in order to better understand the differences in the geotechnical and physical-mechanical characteristics and to verify the presence of any harmful phases for the durability of the concrete.