Hao Sun,Hongjie Bi,Zechun Ren,Xinyuan Zhou,Tong Ji,Min Xu,Zhenhua Huang,Liping Cai
Natural wood has been used as building components for thousands of years due to its abundance, high mechanical strength , and durability. However, suboptimal mechanical performance, moisture sensitivity, and inferior optical performance have severely limited its further development and application prospects. Herein, we fabricated a novel full-wood material based on process of delignification , TEMPO-oxidation, in situ lignin deposition, and densification . The resulting reconstructed wood exhibited excellent optical properties , including ultraviolet-blocking, visible-light transparency, and photothermal conversion ability. Moreover, the densified structure integrated the high mechanical strength (high longitudinal tensile strength of 196.8 MPa and Young's modulus of 24.5 GPa) with significantly high resistance to water. The novel concept of reconstructed wood proposed in this study provides new horizons and design guidance for applications in green energy-efficient buildings, photothermal conversion apparatus, decorative materials, and optical devices.
Although flexible conductive polymeric sensors responding to different stimulus have been extensively explored, it remains challenge to integrate high multi-stimuli sensitivity into one material. Herein, novel electromechanical sensors were fabricated, exhibiting dramatically enhanced strain- and water/moisture-sensitivity. The hybridized nano carbons of graphene and carbon nanotubes (CNTs) were regulated with cellulose nanocrystals (CNCs), followed by embedding into the polymeric elastomer via transfer process. The CNCs not only fragmentized the electromechanical networks under external stress, but also amplified the swelling effect on the conductivity variation as exposed upon water/moisture due to the mechanical reinforcement and amphiphilic nature. Micro/nano cracks were generated on the conductive surface layer, enabling dramatic enhancement on the sensitivity and reversibility in the strain sensing. The gauge factor was up to 1129 within 20% of the strain, which was higher by 182 times compared to that of the control sample without the CNCs content. Moreover, the electromechanical sensors improved the water/moisture sensing whose sensitivity was enhanced by 65 times due to the micro/nano cracks in the fragmentized carbon architecture. The findings extend the application of natural cellulose to exploit multi-stimuli responsive electronics and provide a facial strategy to optimize the sensory performance, which may greatly benefit the developments of the flexible and wearable electronics.
In this study, the novel long-chain active composite rejuvenators (NLCACRs) were composed of long-chain active rejuvenators (LCARs) and aromatic hydrocarbon oil (ArO). Surface free energy method (SFE method), boiling water test method (BWT method) and related parameters were used to evaluate the effect of NLCACRs on interfacial adhesion between aged SBS modified asphalt (ASBS-MA) and granite, and preliminarily predict the moisture sensitivity of asphalt-aggregate system. The results indicated that NLCACRs could increase the surface free energy of ASBS-MA, and the increased range varied with the composition and structure of NLCACRs. The NLCACRs could not only supplement the light components lost by asphalt during aging, but also reconstruct the damaged structure of aged SBS, so they were more effective for the recovery of cohesion work of ASBS-MA. NLCACRs could significantly increase the interfacial adhesion between ASBS-MA and acid granite, and decrease the moisture sensitivity of rejuvenated SBS modified asphalt (RSBS-MA)-granite system. And the results of the BWT method indicated that long-term aging decreased the adhesion grade between SBS modified asphalt and granite from G4 to G2. NLCACRs could restore the adhesion grade of ASBS-MA and granite to the level of original SBS modified asphalt. The comprehensive analysis of the influence of NLCACRs on the interfacial adhesion between ASBS-MA and aggregate showed that the theoretical law (SFE method) was consistent with that of the actual (BWT method). This study could help to explore the influence of NLCACRs on the moisture stability of aged SBS modified asphalt mixture and provide the theoretical basis for its application in practical engineering.
危险品化学品经营许可证（带存储）