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Two-dimensional transition metal dichalcogenides (TMDCs) have shown great promise in electronics and optoelectronics due to their unique electrical and optical properties. Heterostructured TMDC layers such as the laterally stitched TMDCs offer the advantages of better electronic contact and easier band offset tuning. Here, we demonstrate a photoresist-free focused ion beam (FIB) method to pattern as-grown TMDC monolayers by chemical vapor deposition, where the exposed edges from FIB etching serve as the seeds for growing a second TMDC material to form desired lateral heterostructures with arbitrary layouts. The proposed lithographic and growth processes offer better controllability for fabrication of the TMDC heterostrucuture, which enables the construction of devices based on heterostructural monolayers.

For designing and fabricating personalized, cost-effective and biodegradable orthoses, a finger orthosis was chosen as an example to explore a suitable material, personalized design method, and fabrication with a fuse-deposition-modeling (FDM) open-source 3D printer. Thermoplastic polyurethane (TPU)/polylactic acid (PLA) composite filaments were explored for 3D printing. The polymer composite compositions were TPU/PLA: 0 %/100 % (TP0), 25 %/75 % (TP25), and 50 %/50 % (TP50) by weight, respectively. The mechanical performance, thermal properties, and structure of the TPU/PLA composite filaments were assessed by tensile tests, thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and powder X-ray diffraction (XRD) measurements. Compared to the neat PLA, the TP25 specimens exhibited almost the same tensile strength, but its higher elongation at the break indicates that TP25 is more suitable for the material of orthoses. However, a further increase of the TPU ratio to 50 % resulted in a sharp decrease of the tensile strength. The addition of TPU had little effect on the starting thermal decomposition temperature, glass-transition temperature, and melting temperature of the composites. The composite filaments can be printed through the normal 3D printing procedure. 3D scanning and open-source 3D printers can be used to complete the design and fabrication of personalized orthoses.

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Rigid polyurethane (PUR) foam is one of the most important insulating materials used today in the construction industry and is the main insulation material used in the global appliances industry. This study developed rice straw fiber-filled PUF (RPUF) and wheat straw fiber-filled PUF (WPUF) and explored the morphology, sound absorption properties, heat transfer, and compressive strength of the PUF composites. The results indicated that, with the higher fiber content, more open cells were observed in SEM images of the composites. The average sound absorption coefficients (ASAC) of both WPUF and RPUF were significantly increased when 5 per hundred polyols (php) by weight and 10 php fiber contents were added. When fiber contents of 15 php and 20 php were utilized, ASAC reduced due to the tortuosity of cells and large holes in the foam. The sound absorption coefficient (SAC) first increased, then decreased, and increased finally as the sound frequency increased from 100 to 2000 Hz for the two composites. The thermal conductivities of both WPUF and RPUF first decreased and then increased as the fiber content increased from 0 to 20 php. When 5 and 10 php straw contents was added, the thermal conductivities were reduced by 25% to 50% compared to that of the pure PU form (0 php), indicating that the improved thermal insulation ability was obtained. The composite compressive strength was reduced by 19% to 28% due to the fiber addition.

Woodceramics were fabricated in a vacuum through carbonization of wood powder impregnated with phenol formaldehyde (PF) resin. The effects of carbonization temperature and mass ratio of wood/resin on electromagnetic interference (EMI) shielding effectiveness (SE) and morphology of woodceramics were explored. The PF resin made wood cell walls have the characteristics of glassy carbon. Wood axial tracheid and ray cells were filled with more glassy carbon by increasing addition of PF resin. Moreover, the increase of carbonization temperature was beneficial to improving SE. Woodceramics (mass ratio 1:1) obtained at 1000 °C presented a medium SE level between 30 MHz and 1.5 GHz.

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As a natural macromolecule-based biomaterial, fish gelatin is used in medical materials for its low pathogen infection risk. However, because of poor mechanical properties, its application has been limited. In this study, microcrystalline cellulose-reinforced fish gelatin (FG/MCC) composite films were prepared with a biological cross-linking agent (genipin) under ultrasonic treatment. SEM micrographs showed that the smooth microstructure of FG film became increasingly disordered with the addition of MCC. The infrared spectrum analysis (FTIR) demonstrated the existence of hydrogen bond interaction between MCC and FG. Compared with the pure FG film, the tensile strength (TS) and modulus of elasticity (MOE) of composite films with MCC were improved, and the elongation at break (EAB) and swelling ratios (SR) were decreased. Ultrasonic treatment could further improve TS, MOE, and SR. When the composite film was prepared with 15% MCC and treated with ultrasound, the TS and MOE increased by 115% and 227%, respectively, while the EAB decreased by 35% and the SR decreased by 4% in comparison with pure FG films. Thermo-gravimetric analysis (TGA) showed that the FG/MCC composite films were stable below 100 °C. The above results indicate that the FG/MCC films have optimistic application prospects in the biomedical field.