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Fabric-based triboelectric nanogenerators (TENGs) are promising candidates as wearable energy-harvesting devices and self-powered sensors. Booting the power generation performance is an eternal pursuit for TENGs. Herein, an efficient approach was proposed to enhance the triboelectric performance of commercial velvet fabric by enriching the fiber surface with hierarchical structures and amide bonds through chemical grafting of carbon nanotube (CNT) and poly­(ethylenimine) (PEI) via a polyamidation reaction. With an optimized modifier concentration, the fabric-based TENG easily achieved over 10 times improvement in output voltage and current at a low modifier content of less than 1 wt %. The modified-fabric-based TENG was fully washable and exhibited excellent robustness and long-term stability. With a maximum power density of 3.2 W/m2 achieved on a 5 × 106 Ω external resistor, the TENG was able to serve as a power source for various small electronics such as pedometer, digital watch, calculator, and digital timer. In addition, the TENG demonstrated capability in self-powered tactile and pressure sensing and promising potential in human–computer interface applications. The approach proposed provides a feasible path for boosting the triboelectric performance of fabric-based TENGs and gives insights into the design of fabric-based nanogenerators and smart textiles.

The uptake, accumulation, and long-distance transport of organophosphate esters (OPEs) in four kinds of plants were investigated by hydroponic experiments. The uptake kinetics (k 1,root) of OPEs in plant roots were determined by the binding of OPEs with the proteins in plant roots and apoplastic sap for the hydrophobic compounds, which correlated well with the transpiration capacity of the plants for the hydrophilic compounds. However, the accumulation capacity of OPEs in plant root was controlled by the partition of OPEs to plant lipids. As a consequence, OPEs were taken up the fastest in wheat root as a result of its highest protein content but least accumulated as a result of its lowest lipid content. The translocation factor of the OPEs decreased quickly with the hydrophobicity (log K ow) increasing, suggesting that the hydrophobic OPEs were hard to translocate from roots to shoots. The hydrophilic OPEs, such as tris­(2-chloroisopropyl) phosphate and tris­(2-butoxyethyl) phosphate, were ambimobile in the plant xylem and phloem, suggesting that they could move to the edible parts of plants and enhanced risk to human health.

A simple strategy tailors perfusable and permeable hierarchical microchannel networks from diverse materials.

The impacts of a model globular protein (bovine serum albumin, BSA) on aggregation kinetics of graphene oxide (GO) in aquatic environment were investigated through time-resolved dynamic light scattering at pH 5.5. Aggregation kinetics of GO without BSA as a function of electrolyte concentrations (NaCl, MgCl, and CaCl) followed the traditional Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, and the critical coagulation concentration (CCC) was 190, 5.41, and 1.61 mM, respectively. As BSA was present, it affected the GO stability in a concentration dependent manner. At fixed electrolyte concentrations below the CCC values, for example 120 mM NaCl, the attachment efficiency of GO increased from 0.08 to 1, then decreased gradually and finally reached up to zero as BSA concentration increased from 0 to 66.5 mg C/L. The low-concentration BSA depressed GO stability mainly due to electrostatic binding between the positively charged lysine groups of BSA and negatively charged groups of GO, as well as double layer compression effect. With the increase of BSA concentration, more and more BSA molecules were adsorbed on GO, leading to strong steric repulsion which finally predominated and stabilized the GO. These results provided significant information about the concentration dependent effects of natural organic matters on GO stability under environmentally relevant conditions.

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Repairing irregular-shaped bone defects poses enormous challenges. Scaffolds that can fully fit the defect site and simultaneously induce osteogenesis and angiogenesis hold great promise for bone defect healing. This study aimed to produce superelastic organic/inorganic composite aerogel scaffolds by blending silica nanofibers (SiO 2 ) and poly (lactic acid)/gelatin (PLA/gel) nanofibers; the content of SiO 2 nanofibers is varied from 0-60 wt% (e.g., PLA/gel, PLA/gel/SiO 2 -L, PLA/gel/SiO 2 -M, and PLA/gel/SiO 2 -H for 0%, 20%, 40%, and 60% of SiO 2 nanofibers, respectively) to produce a range of scaffolds. The PLA/gel/SiO 2 -M scaffold has excellent elasticity and good mechanical properties. In vitro experiments demonstrate that the silicon ions released from PLA/gel/SiO 2 -M scaffolds promote the differentiation of rat bone marrow-derived mesenchymal stem cells into osteoblasts, enhancing alkaline phosphatase activity and bone-related genes expressions. The released silicon ions also promote the proliferation of human umbilical vein endothelial cells and the expression of vascular endothelial growth factors, thereby promoting angiogenesis. The assessment of these scaffolds in a calvarial defect model in rats shows good potential of PLA/gel/SiO 2 -M to induce bone regeneration as well as promote osteogenesis and angiogenesis. Overall, these organic/inorganic composite scaffolds have good biological activity, which may have broad applications for tissue engineering.