Feifan Xie

To address the global challenge of desertification, it is essential to develop sustainable and biodegradable materials for sand fixation to support ecological restoration in arid regions. In this work, a CNS/PAM biocomposite system was constructed through the supramolecular assembly of highly flexible two-dimensional cellulose nanosheets (CNS) and polyacrylamide (PAM). Benefiting from the flexible layered structure of CNS and the abundant hydroxyl and carboxyl groups on their surface, a conformal coating and an interparticle bridging network were formed via hydrogen bonding and coordination interactions with mineral cations. The introduction of PAM further regulated the hydrogen-bonding network, which improved structural uniformity and mechanical integrity. The resulting composites showed strong resistance to both wind and water erosion (erosion loss < 0.1%) and reached a compressive strength of up to 0.23 MPa, while maintaining good environmental compatibility. This study clarifies the structure–interaction–property relationships of cellulose nanosheet-based supramolecular assemblies and provides a new theoretical basis and practical pathway for designing biodegradable sand-fixing materials.

Wood, being a natural hygroscopic material, the interaction between wood and moisture plays a crucial role in wood processing and utilization. Moisture affects the physical and mechanical properties of wood, and is also one of the main external factors that cause wood deformation and cracking. Drying shrinkage is a common phenomenon during the processing and utilization of wood induced by moisture loss. Drying stress is the main cause of wood deformation and cracking. The shrinkage differential between tangential and radial direction and moisture content gradient of wood are two reasons induced the generation of drying stresses. In this review, the existing states of moisture in wood and the interaction between water molecules and wood components were systematically summarized. The current research progress and deficiencies in three aspects including the factors resulted in deformation and cracking in wood caused by moisture loss, the correlation between wood mechanical properties and moisture, as well as the development of deformation and cracking in wood under moisture loss were discussed. This review aims to facilitate further research on the deformation and cracking of wood under moisture loss by providing valuable insights and assistance, ultimately reducing the occurrence of wood deformation and cracking. And thus, it will enhance the overall utilization of wood resources, making wood better serve human life.

The effects of CH₃COOH and Na₂SO₃ pretreatment on the structural properties and hydrolyzability of fast-growing Paulownia elongate were investigated. Acetic acid increased cellulose’s crystallinity and hydrolyzability when combined with alkaline sodium sulfite and sodium hydroxide. The cellulose content increased by 21%, the lignin content decreased by 6%, and the product showed better enzymatic digestibility. With a cellulase dose of 30 FPU/g DM, after 72 h hydrolysis, the hydrolysis yields of glucose and xylose were 78% and 83%, respectively, which were 51% and 69% higher than those of untreated materials. When the enzyme dosage was 20 FPU/g DM, after 72 h hydrolysis, the hydrolysis yields of glucose and xylose were 74% and 79%, respectively. The high hydrolyzability, low enzyme loading, and high hydrolysis yield demonstrate the potential of the proposed system for producing platform sugars from fast-growing Paulownia elongate.