Processing and bioactivity of 45S5 Bioglass®-graphene nanoplatelets composites

Well dispersed 45S5 Bioglass^® (BG)-graphene nanoplatelets (GNP) composites were prepared after optimising the processing conditions. Fully dense BG nanocomposites with GNP loading of 1, 3 and 5 vol% were consolidated using Spark plasma sintering (SPS). SPS avoided any structural damage of GNP as confirmed using Raman spectroscopy. GNP increased the viscosity of BG-GNP composites resulting in an increase in the sintering temperature by ~50 °C compared to pure BG. Electrical conductivity of BG-GNP composites increased with increasing concentration of GNP. The highest conductivity of 13 S/m was observed for BG-GNP (5 vol%) composite which is ~9 orders of magnitude higher compared to pure BG. For both BG and BG-GNP composites, in vitro bioactivity testing was done using simulated body fluid for 1 and 3 days. XRD confirmed the formation of hydroxyapatite for BG and BG-GNP composites with cauliflower structures forming on top of the nano-composites surface. GNP increased the electrical conductivity of BG-GNP composites without affecting the bioactivity thus opening the possibility to fabricate bioactive and electrically conductive scaffolds for bone tissue engineering.     

Numerical simulations of cracked plate using XIGA under different loads and boundary conditions

This article deals with the numerical simulation of cracked plate using extended isogeometric analysis (XIGA) under different loads and boundary conditions. The plate formulation is done using first-order shear deformation theory. The crack faces are modeled by the Heaviside function, whereas the singularity in stress field at the crack tip is modeled by crack tip enrichment functions. The stress intensity factors for the cracked plate are numerically computed using a domain-based interaction integral. The results obtained by XIGA for the center and edge crack plate are compared with extended finite element method and/or literature results for different types of loads and boundary conditions.     

Quantitative determination of antioxidants and ultraviolet stabilizers in polymers by high performance liquid chromatography

The quantitative determination of antioxidants and ultraviolet (UV) stabilizers in a polymer matrix has been standardized using HPLC. The additives were extracted out of the matrix using low boiling solvents in order to minimize the degradation of additives at elevated temperatures. Carbon tetrachloride and tetrahydrofuran have been found to be most suitable solvents for low density polyethylene and polypropylene respectively. The method has been found to be highly reproducible and the standard deviation is very low. This method does not suffer from the problems like overlapping frequencies as observed in spectroscopic methods.     

Optimization of association rules using hybrid data mining technique

Innovations in Systems and Software Engineering - Software quality has been the important area of interest for decades now in the IT sector and software firms. Defect prediction gives the tester...     

Dragonfly-based swarm system model for node identification in ultra-reliable low-latency communication

Neural Computing and Applications - Latency and reliability are essential parameters for enabling ultra-reliable low-latency communication (URLLC). Therefore, an approach for node identification...     

Methane pyrolysis in a molten gallium bubble column reactor for sustainable hydrogen production: Proof of concept & techno-economic assessment

Nowadays, nearly 50% of the hydrogen produced worldwide comes from Steam Methane Reforming (SMR) at an environmental burden of 10.5 t_CO2,eq/t_H2, accelerating the consequences of global warming. One way to produce clean hydrogen is via methane pyrolysis using melts of metals and salts. Compared to SMR, significant less CO₂ is produced due to conversion of methane into hydrogen and carbon, making this route more sustainable to generate hydrogen. Hydrogen is produced with high purity, and solid carbon is segregated and deposited on the molten bath. Carbon may be sold as valuable co-product, making industrial scale promising. In this work, methane pyrolysis was performed in a quartz bubble column using molten gallium as heat transfer agent and catalyst. A maximum conversion of 91% was achieved at 1119 °C and ambient pressure, with a residence time of the bubbles in the liquid of 0.5 s. Based on in-depth analysis of the carbon, it can be characterized as carbon black. Techno-economic and sensitivity analyses of the industrial concept were done for different scenarios. The results showed that, if co-product carbon is saleable and a CO₂ tax of 50 euro per tonne is imposed to the processes, the molten metal technology can be competitive with SMR.     

A high payload reversible data hiding algorithm for homomorphic encrypted absolute moment block truncation coding compressed images

Multimedia Tools and Applications - With the aim to ensure privacy and security of secret message, an enhanced reversible data hiding algorithm in encrypted as well as compressed domain is proposed...