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The effect of 5-MeV electron accelerator irradiation of 400 kGy on the formic acid cycling separation of cellulose, lignin, and xylose from Triarrhena lutarioriparia (TL) were studied, and the enzymatic conversion rate and structural characteristics of TL cellulose were analyzed. For 400 kGy irradiated TL, the results revealed that the average purity of cellulose was 81.13% and the recovery of lignin and xylose were 28.68% and 10.16%, respectively, which were higher than those of the unirradiated sample. The recovery of cellulose, concentration of xylose, and purity of lignin increased with the increase in cycle times. The final concentration of xylose for pre- and post-irradiated TL were 31.35 mg/mL and 37.35 mg/mL, respectively, and the purity of lignin was more than 90%. Fourier transform infrared and X-ray diffraction results revealed that TL cellulose separated by formic acid were formylated and exhibited high crystallinity. The enzymatic conversion rate of TL cellulose was 54.30%–57.47% after hydrolysis for 120 h, this rate was considerably higher than that of TL. These results indicated that the formic acid recycling fractionation process could effectively separate TL lignocellulosic components, which could support its large-scale utilization.

The 3D freeze printing (3DFP) of nanocellulose aerogels are demonstrated with large‐scale aligned pore orientations as a sustainable alternative to current acoustical materials. In contrast with the unidirectional pore network orientations obtained from current 3DFP techniques, a bidirectional orientation is achieved by using an inhomogeneous printing substrate to alter the thermal gradient within the print volume. The microstructural morphology shows that bidirectional printing results in a 2D pore orientation, with comparatively thinner pore walls and larger pore widths. Acoustic measurements reveal that altering the pore network characteristics significantly affects the acoustical behavior of the printed CNC aerogels; the wider pores allow the bidirectional CNC aerogels to provide higher sound absorption performance at lower frequencies than the unidirectional samples. Notably, both 3D Freeze printed CNC aerogels provide substantially higher sound transmission loss performance as compared to current acoustical materials. The unidirectional pore structure results in CNC aerogels with higher stiffness and improved energy absorption performance, with both 3D freeze printed CNC aerogels outperforming other CNC aerogel materials in their stiffness‐to‐density ratios. The ability to simultaneously control their pore orientation and macrostructural geometry paves the way for printing complex shaped CNC aerogel structures for multifunctional noise control applications. [ABSTRACT FROM AUTHOR]

The concept for fabrication of waveguides by an in‐volume laser direct writing in single‐crystal silicon is explored using a nanosecond pulse laser. The key innovation of this technology relies on the generation of amorphous silicon, which has a higher refractive index than that of crystalline silicon. Herein, transmission electron microscopy (TEM) together with selected area electron diffraction (SAED) and high‐resolution TEM (HRTEM) characterizations are used to better understand the microstructural evolutions. TEM images reveal the core‐shell structures, while SAED patterns and HRTEM directly observe the presence of amorphous silicon in the core surrounded by a crystalline silicon shell. With a lower laser scanning speed, a higher density of defects yet less amorphous silicon is formed by laser direct writing. [ABSTRACT FROM AUTHOR]

One-dimensional carbon nanomaterials such as carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) are promising for future applications in nanoelectronics and nanophotonics due to their unique characteristics such as topological edge states, chirality, and quantum confinement. Despite the chemical unzipping method of producing GNRs from CNTs, using energetic photons to control light–matter interaction and shape materials at the nanoscale has great promise, especially for chemical-free and on-demand manufacturing. Here, we exploit the high electromagnetic field from a Ti:Sapphire femtosecond laser to interact with CNTs, causing ultrafast energy transfer between the photons and the nanotubes and converting them to GNRs and carbon nanocrystals. Probed with scattering-type scanning near-field optical microscopy, the nanoribbons are identified as semiconducting and/or insulating, a strikingly different electronic phase compared with the original metallic CNTs. Our method of employing high-field and nonequilibrium processes with an ultrafast laser to alter the shape and transform the electronic properties is scalable, does not necessitate high-temperature processes, and is highly spatially controllable—conditions that pave the way for manufacturing nanoscale hybrid materials and devices. [ABSTRACT FROM AUTHOR]