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The prime objective of the current research work was to understand the role of microwave-assisted pyrolysis for the upgradation of expanded polystyrene (EPS) waste into valuable aromatic hydrocarbons. Ethyl acetate solvent was used to dissolve the EPS to enhance the homogeneous dispersion of EPS with susceptor particles. Biochar obtained from the pyrolysis was used as a susceptor. The design of experiments method was used to understand the role of microwave power (300 W, 450 W, and 600 W) and susceptor quantity (5 g, 10 g, and 15 g) in the pyrolysis process. The pyrolysis was conducted till the temperature reached up to 600 °C, and this temperature was achieved in the time interval of 14–38 min based on the experimental conditions. The obtained average heating rates varied in the range of 15 to 41 °C/min to attain the pyrolysis temperature. The EPS feed was converted into char (~ 2.5 wt.%), oil (51 to 60 wt.%), and gaseous (37 to 47 wt.%) products. The specific microwave energy (J/g) was calculated to know the energy requirement; it increased with an increase in susceptor quantity and microwave power, whereas specific microwave power (W/g) was a function of microwave power and increased from 15 to 30 W/g. The predicted values calculated using the model equations closely matched the actual values showing that the developed model equations via optimization had a good fit. The obtained pyrolysis oil physicochemical properties including viscosity (1 to 1.4 cP), density (990 to 1030 kg/m3), heating value (39 to 42 MJ/kg), and flash point (98 to 101 °C) were thoroughly analyzed. The pyrolysis oil was rich in aromatic hydrocarbons and it was predominantly composed of styrene, cyclopropyl methylbenzene, and alkylbenzene derivates. [ABSTRACT FROM AUTHOR]

Hip joint replacement surgeries, specifically total hip arthroplasty (THA), play a crucial role in improving the patient’s range of motion and decreasing discomfort caused by damaged hip joints. Unfortunately, obstacles such as stress on the affected area (stress shielding), bone deterioration, and implant malfunctions continue to persist. To address these challenges, the present study delves into lightweight and porous hip implants, specifically those featuring Triply Periodic Minimal Surfaces (TPMS), using finite element analysis (FEA). TPMS-based hip implants, namely, Gyroid and Split-P structures, are modeled as per industry standards and compared with the traditional Solid implant. Computer tomography (CT) has been taken of a femur bone. The resulting Digital Imaging and Communications in Medicine (DICOM) images have been converted to 3D model using 3D Slicer software. Each of the 3D modeled implants is assembled with femur bone, and finally, FEA has been conducted as per ISO 7206–4:2010 standard and then compared for overall stress distribution, strain, and deformation. Split-P implant resulted in the highest stress concentrations, against the Gyroid implant, which showed stress levels well below the critical limits. Additionally, a Gyroid-based implant resulted in a 28% weight reduction as compared to the Solid implant and concluded as an excellent choice among the three implants. With a porosity of 70% against the Solid, a Gyroid implant is an excellent choice for osteointegration, thereby assisting bone growth and tissue regeneration. This study provides crucial insights while designing hip implants leading for better treatment options and elevated standards in orthopedic surgery. [ABSTRACT FROM AUTHOR]