Industrial Crops and Products最新文献

Flexible conductive hydrogel fibers have captured considerable attention in wearable electronic devices due to the remarkable flexibility and heightened sensitivity. However, seldom attention has been directed towards the flexible conductive hydrogel fibers that integrate remarkable strength, stretchability, anti-freezing property and wide linear sensing range. Herein, the TEMPO-oxidized cellulose nanofibers-carbon nanotubes/poly(vinyl alcohol)-sodium alginate-tannic acid (TOCNs-CNTs/PVA-SA-TA, TCG) hydrogel fibers are fabricated through the facile microfluidic spinning. TA enhances the mechanical toughness of TCG by establishing richer hydrogen bonds with the double network structure constructed by PVA and SA. TOCNs not only contribute to the homogeneous dispersion of CNTs to form connected conductive networks, but also act as nano-reinforcement to strengthen the matrix. The as-prepared fibers exhibit excellent mechanical properties, including a tensile strength of 8.06 MPa and a strain at break of 438 %. Furthermore, the fibers demonstrate remarkable electrical conductivity (1.57 S m⁻¹) and anti-freezing performance at temperature below −20℃. The sensors based on TCG successfully detect human motions due to the wide detection range (0–250 %), high sensitivity (gauge factor = 2.49 at 250 % strain), fast response time (120 ms) and excellent fatigue resistance (500 cycles), substantiating a great potential for application in flexible wearable devices.

Tannin-based adhesives, as a natural biobased adhesive, have the potential to expand their application in wood industry as substitutes for traditional adhesives. In this study, cellulose nanofibrils and hyperbranched polyamides (HBPA) were studied to address the challenges associated with the low crosslinking degree and poor water resistance characteristics of condensed tannin-based wood adhesives. The modification strategy focuses on grafting oxidized cellulose nanofibrils with hyperbranched polyamides through the Schiff base reaction. Comprehensive analyses, including FTIR, XPS, XRD, and TG, confirm the successful binding of oxidized cellulose nanofibrils with hyperbranched polyamides, demonstrating their potential to enhance the properties of tannin adhesives. Furthermore, the investigation about bonding strength, and water resistance of tannin adhesives reveal significant improvements in the mechanical and water resistance properties through this modification strategy. In particular, the maximum wet shear strength is 0.7 MPa, meeting the requirements for Class II plywood. This study provides valuable insights into improving the performance of tannin adhesives, offering promising implications for broader applications and contributing to eco-friendly practices in the wood industry.

Natural fiber-reinforced polylactic acid (PLA) composites possess renewability, good mechanical properties, and biodegradability. To enhance the mechanical properties of natural fiber-reinforced composites, the flax/PLA braided yarns were woven into three-dimensional orthogonal fabrics with an integrated structure. After the fabrics was hot-pressed, three-dimensional flax/PLA composites with the flax/PLA mass ratios of 50/50 and 25/75 were formed. The results showed that the 50/50 ratio exhibited the higher tensile strength (70.20 MPa) and flexural strength (172.99 MPa), respectively. Thermal analysis indicated its enhanced thermal stability, with the main degradation regions at 354.3°C and 394.7°C. In addition, FTIR spectroscopy showed that the flax/PLA composites exhibited a glass transition temperature of 83.88°C and a melting temperature of 172.89°C. Compared to recent studies, the newly developed three-dimensional orthogonal flax/PLA composites demonstrated superior performance, indicating their potential applications in the field of biodegradable composites, particularly in high-load-bearing applications.

In this study, areca/ ramie fibre-reinforced hybrid composites were fabricated by modifying the weight percentage of graphene nanoparticles (0.50 wt%, 1.0 wt%, 1.50 wt%, 2.0 wt%) using the compression moulding technique. Graphene-reinforced adhesives were prepared using the ultrasound sonication method. The structural behaviour of the hybrid composite was evaluated through tensile, flexural, and impact analyses. The experimental findings indicated that the inclusion of 1.5 wt% graphene significantly increased the tensile strength, flexural strength, and impact energy of the hybrid composite by 187.88 %, 143.17 %, and 159.66 %, respectively. This substantial improvement in mechanical properties lays a solid foundation for the potential engineering applications of these composites. Free vibrational analysis showed that the presence of graphene-enhanced the fundamental natural frequencies of the hybrid composite because of enhanced bonding between natural fibres and the epoxy matrix. Atomic force microscopy (AFM) revealed the uniform dispersion of the 1.5 wt% graphene in the epoxy matrix. Furthermore, FE-SEM results demonstrated the formation of resin-rich areas, better fibre/matrix adhesion, matrix damage, voids, and agglomerated areas in the hybrid composite. The water absorption rate decreased with the existence of graphene, reducing the void content and physically hindering the infiltration of water molecules into the hybrid composite. The present research emphasises the potential of using a hybrid composite material prepared with areca and ramie fibres, combined with an optimal wt% of graphene powder. The proposed composite material shows great promise for various weight-sensitive engineering applications such as automotive, marine, and aerospace industries, where lightweight interior structures are essential.

Potatoes are a widely consumed food globally, but their tendency to sprout during storage can result in decreased yields and quality losses. Researchers have explored various methods to prevent or delay sprouting, including the use of synthetic chemicals like chlorpropham (CIPC). However, concerns about the potential environmental and health impacts of CIPC have led to an increased interest in alternative sprout suppressors such as essential oils (EOs). This study aimed to investigate the efficacy of EOs as sprout suppressants for potato storage at room temperature. Two experiments were conducted as part of this study. In the first experiment, potato cv. Australian Crescent fingerling potato tubers were used to test the effectiveness of nine EOs (pennyroyal (Mentha pulegium L.), Peru balsam (Myroxylon pereirae L.), pink pepper (Schinus molle L.), rose absolute (Rosa damascena L.), garden sage (Salvia officinalis L.), scotch pine (Pinus sylvestris L.), spearmint (Mentha spicata L.), St John's Wort (Hypericum perforatum L.) and tagetes (Tagetes minuta L.)) in controlling sprouting, and how the effectiveness evolves at different storage times using Repeated Measures Analysis. In the second experiment, the optimum proportion of three EO blends of garlic (Allium sativum L.), blue mallee eucalyptus (Eucalyptus polybractea R.T.Baker), and southern blue gum (Eucalyptus globulus Labill.) that suppresses sprout of potatoes was determined using Mixture experimental design. Among the nine EOs tested, Mentha spicata was the most effective in suppressing potato tuber sprout length and number. Salvia officinalis EO suppressed sprouting until 60 days, while Mentha pulegium EO significantly reduced sprout growth. The EO blends with Allium sativum and Eucalyptus polybractea consistently demonstrated the ability to shorten and restrict sprouts at multiple time points during storage. These findings suggest that certain EOs may serve as sprout inhibitors for potato storage at room temperature (20-22°C), providing valuable alternatives for sprout control in both the organic and the conventional sectors.

Bamboo is a natural composite material with a unique structure. Establishing the relationship between the structure and mechanical characteristics of bamboo is crucial for its industrial applications. In this paper, we developed a non-destructive testing system using finite element analysis (FEA) and machine learning (ML) to predict the axial compression performance of Phyllostachys edulis. The results showed that the volume fraction of fiber sheaths (FS) was positively correlated with their axial compression performance. Under axial loading, all bamboo blocks exhibited stages of linear elastic deformation, elastic–plastic, and plastic plateau. The displacements to reach the proportional limit, yield point, and maximum point decreased with the increase in the volume fractions of FSs. The ML, incorporating the tree model (DT), random forest model (RF), gradient enhanced random forest regression model (GERFR), and support vector machine linear model (SVM) was able to predict the axial compression strength of the bamboo blocks, with an accuracy of 91 % for the SVM. In the compression experiments, five failure models were observed, with samples containing a high volume fraction of FSs being more prone to shear failure. In addition, our study indicated that the FEA accurately simulated the stress distribution and potential failure types when bamboo is under compression. This not only validated the results of the axial compression experiments but also underscored the potential of FEA as a predictive tool. Overall, this study introduces novel and effective methods for predicting the mechanical properties of bamboo, enabling rapid assessment of its structural characteristics.