Glycolic acid (GA), as an anti-aging skincare ingredient, plays a pivotal role in anti-aging treatment. However, its benefits could be overshadowed due to its side effects including skin burning and irritation when overused. Bacterial cellulose (BC) is a highly pure form of cellulose, biosynthesized in the form of a swollen membrane by several kinds of bacteria that was demonstrated to modulate the release of model drugs owing to its porous and 3D fibrous network structure, and glycerol (GL), as a plasticizer, could enhance the controlled drug delivery. Herein, we report a topical controlled drug delivery system based on BC membrane, GA and GL for controlling sustainable release of GA to reduce its side effects on the skin, while maintaining its prolonged and maximum therapeutic effect. The results showed that the incorporation of GL increased the malleability and flexibility of BC/GA/GL membrane, as compared with BC/GA membrane. In addition, the GL enhanced the control of the GA delivery, as evidenced by a higher swelling capacity and thereby a slower release of the GA from BC/GA/GL membrane. More importantly, in vitro study indicated that both BC/GA and BC/GA/GL membranes could effectively stimulate endogenous collagen synthesis in NIH3T3 cells owing to the release of GA, and that BC/GA/GL membrane is more conducive to a long-term cell adhesion, spreading, and proliferation of NIH3T3 and HaCaT cells due to its lower and sustainable release of GA than BC/GA membrane. This study suggests the BC/GL/GA composite membrane holds great promise as an appealing platform to control the release of GA to greatly promote renewal of skin cells for effective anti-aging treatment.

In this study, we report the fabrication of nitrogen rich activated nanosized carbon with hierarchical micro/mesoporous and ultrahigh specific surface area by template-free and one-step carbonization-activation method, which greatly simplified the process and avoided the waste of reagents. Chitin nanoparticles were prepared by a mechanical induced sol-gel transition process in NaOH/Urea solvent and a subsequent carbonization utilizing NaOH for activation and urea for N doping, resulting in activated carbon (ACNC-800) with extraordinary specific surface area (2631 m²/g) and high nitrogen content (7.1%). Further characterization and electrochemical tests demonstrate high electrochemical performance of the activated nanocarbon. Under the current density of 0.5 A/g, the specific capacitance of the three-electrode system is 245 F/g and that of the two-electrode system is 227 F/g. The assembled capacitors exhibit superior rate performance and good cycle stability (98% capacitance retention after 10000 charge-discharge cycles). This work introduces a simple and efficient strategy to prepare N-doped carbon with hierarchical porosity applied to high performance supercapacitors.

Application of out-of-service rubber from a variety of sources is of both environment-protecting and resource-saving importance. To that end, recycled tire rubber was utilized as a filler to fabricate wood-high density polyethylene (HDPE) composite with enhanced toughening performance using the injection procedure in this work. Dosages of rubber powders were 0, 5, 10, and 15wt% based on the overall weight of poplar wood flour and HDPE (HDPE: wood flour = 70꞉30). The injection-fabricated composites were subjected to a four-cycle repetitive compressing loadings (0–3 kN) and dynamical mechanical analysis (DMA, room temperature to 150 ℃, in the dual cantilever mode). It was found that the rubber-filled materials exhibit advantageous energy absorption performance compared to wood-HDPE composites under repetitive compressions. The rubber-filled wood-HDPE composites are thermomechanically labile in an environment with raised temperature. The HDPE matrix substance occupies the predominant role in thermally yielding of the overall composite, typically in the temperature range of 50–75 ℃ resulting in a loss modulus peak. Up to 130–150 ℃, all the composites fully loses their moduli with loss factor (Tanδ) reaching its peak values of 0.30–0.38. To conclude, rubber-filled wood-HDPE is a qualified material applicable in proper temperature range.

Rice husks obtained from upland and lowland rice varieties were characterized for composition and content of ash. Each of the rice husk varieties was fired at temperatures of 600, 800 and 900 ℃ for a soaking period of 3 h. The resultant rice husk ash was analyzed for oxide composition and crystallinity using X-ray fluorescence and diffraction techniques, respectively. The generated amorphous ash with the highest silica content, together with metakaolin, aggregate, water, and an alkaline activator was employed to formulate geo-polymer mortar prisms according to the standard EN 196–1. Results showed that the content of ash in the varieties ranged from 18.3% to 28.6% dry basis. Out of this, 89 wt%–96 wt% was silica, with amorphous and crystalline forms of silica obtained at 600 ℃ and 900 ℃, respectively, regardless of the rice variety. However, at 800 ℃, the silica in the generated ash exhibited both amorphous and crystalline forms. The amorphous ash generated at 600 ℃ was used in formulation of geopolymer mortars. Compressive and flexural strength of the formulated mortar after 7 days of curing was 1.5 and 1.3 MPa, respectively. These results reveal the firing protocol to form pozzolanic ash, with potential applications in mortar production.

Cellulose nanocrystals isolated from water hyacinth fiber (WHF) have been studied as a reinforcement for polyvinyl alcohol (PVA)-gelatin nanocomposite. Central composite design was used to study and optimize effects of the PVA, gelatin and cellulose nanocrystal (CNC) concentration on tensile strength and elongation of formed films. The results of this study showed that WHF CNC had a diameter range of 20–50 nm produced films reaching 13.8 MPa tensile strength. Thermal stability of the films was improved from 380 ℃ to 385 ℃ in addition of CNCs and maximum storage modulus of 3 GPa were observed when 5 wt% CNC was incorporated. However, water absorption, water vapour permeability (WVP) and moisture uptake of the films decreased in addition of CNC to the PVA-gelatin blends. Moisture uptake decreased from 22.50% to 19.05% while the least WVP when 10 wt% CNC added was 1.64 × 10^–6 g/(m•h•Pa). These results show possibility for industrial application of WHF CNC and PVA-gelatin blends in biodegradable films for on-the-go food wrappers.