Additive manufacturing has enhanced medical trainers and their functionality, but synthetic tissues that are both anatomically accurate and capable of replicating musculoskeletal load responses remain largely unexplored. The purpose of this study is to demonstrate fabrication of synthetic tissue using active filament-mixing fabrication to enable local composition control with thermoplastic compositions tuned to match the modulus of elasticity of the respective tissues and functionally graded transitions between ligament and bone. Synthetic femoral anterior cruciate ligament (ACL) tibial complexes were fabricated and tested at 30° flexion along the tibial and anatomical load orientations matching the test procedure performed on cadaveric femoral ACL tibial complexes by Woo et al. in 1991. Load parameters were facilitated by section grips integrated into the design of test specimens without requiring a multi-axis jig. Anatomical accuracy was achieved by modeling tissues from magnetic resonance imaging data. Specimens loaded in the tibial orientation have an ultimate load of 287 ± 37 N and stiffness of 62.8 ± 11 N/mm. Specimens loaded in the anatomical orientation have an ultimate load of 312 ± 6.5 N and a stiffness of 43.5 ± 3.4 N/mm. Although load response in the synthetic tissue was less than its cadaveric counterpart due to bending load from flexion, the methods of this study are versatile, repeatable, and compatible with a wide variety of printable thermoplastics and composites which can be applied to other tissues, joints, and load conditions.

FeAl_xO_y powders, fabricated by solution combustion synthesis (SCS), are promising catalysts for microwave-assisted pyrolysis of methane. However, the effects of SCS parameters on the pyrolysis are not well understood. In the present work, two fuels (citric acid and glycine), two Fe:Al molar ratios, and two heating modes (a hotplate and a muffle furnace) are tested. All catalysts exhibit CH₄ conversion of around 70% and H₂ composition of about 93%. The process is one to two orders of magnitude more efficient than conventional pyrolysis. Increasing the Fe:Al ratio from 1:1 to 2:1 and using a hotplate improve H₂ generation efficiency. Use of glycine decreases the CO₂:H₂ ratio, but citric acid yields more readily reducible products due to differences in phase evolution, detected by X-ray diffraction analysis. Scanning electron microscopy and energy-dispersive X-ray spectroscopy reveal carbon nanotubes and exsolution of Fe. FeAl_xO_y catalysts, prepared via incipient wetness impregnation, are ineffective.