Donghua University

About: Donghua University is a education organization based out in Shanghai, China. It is known for research contribution in the topics: Fiber & Nanofiber. The organization has 21155 authors who have published 21841 publications receiving 393091 citations. The organization is also known as: Dōnghuá Dàxué & China Textile University.

Continuous and Scalable Manufacture of Hybridized Nano-Micro Triboelectric Yarns for Energy Harvesting and Signal Sensing.

Abstract: Textile-based triboelectric nanogenerators (TENG) that can effectively harvest biomechanical energy and sense multifunctional posture and movement have a wide range of applications in next-generation wearable and portable electronic devices. Hence, bulk production of fine yarns with high triboelectric output through a continuous manufacturing process is an urgent task. Here, an ultralight single-electrode triboelectric yarn (SETY) with helical hybridized nano-micro core-shell fiber bundles is fabricated by a facile and continuous electrospinning technology. The obtained SETY device exhibits ultralightness (0.33 mg cm-1), extra softness, and smaller size (350.66 μm in diameter) compared to those fabricated by conventional fabrication techniques. Based on such a textile-based TENG, high energy-harvesting performance (40.8 V, 0.705 μA cm-2, and 9.513 nC cm-2) was achieved by applying a 2.5 Hz mechanical drive of 5 N. Importantly, the triboelectric yarns can identify textile materials according to their different electron affinity energies. In addition, the triboelectric yarns are compatible with traditional textile technology and can be woven into a high-density plain fabric for harvesting biomechanical energy and are also competent for monitoring tiny signals from humans or insects.

Electrophoretic Deposition of Dexamethasone-Loaded Mesoporous Silica Nanoparticles onto Poly(l-Lactic Acid)/Poly(ε-Caprolactone) Composite Scaffold for Bone Tissue Engineering

Abstract: The incorporation of microcarriers as drug delivery vehicles into polymeric scaffold for bone regeneration has aroused increasing interest. In this study, the aminated mesoporous silica nanoparticles (MSNs-NH2) were prepared and used as microcarriers for dexamethasone (DEX) loading. Poly(l-lactic acid)/poly(e-caprolactone) (PLLA/PCL) nanofibrous scaffold was fabricated via thermally induced phase separation (TIPS) and served as template, onto which the drug-loaded MSNs-NH2 nanoparticles were deposited by electrophoretic deposition (EPD). The physicochemical and release properties of the prepared scaffolds (DEX@MSNs-NH2/PLLA/PCL) were examined, and their osteogenic activities were also evaluated through in vitro and in vivo studies. The release of DEX from the scaffolds revealed an initial rapid release followed by a slower and sustained one. The in vitro results indicated that the DEX@MSNs-NH2/PLLA/PCL scaffold exhibited good biocompatibility to rat bone marrow-derived mesenchymal stem cells (BMSCs). Also, BMSCs cultured on the DEX@MSNs-NH2/PLLA/PCL scaffold exhibited a higher degree of osteogenic differentiation than those cultured on PLLA/PCL and MSNs-NH2/PLLA/PCL scaffolds, in terms of alkaline phosphatase (ALP) activity, mineralized matrix formation, and osteocalcin (OCN) expression. Furthermore, the in vivo results in a calvarial defect model of Sprague-Dawley (SD) rats demonstrated that the DEX@MSNs-NH2/PLLA/PCL scaffold could significantly promote calvarial defect healing compared with the PLLA/PCL scaffold. Thus, the EPD technique provides a convenient way to incorporate osteogenic agents-containing microcarriers to polymer scaffold, and thus, prepared composite scaffold could be a potential candidate for bone tissue engineering application due to its capacity for delivery of osteogenic agents.

Metal-Free Multi-Heteroatom-Doped Carbon Bifunctional Electrocatalysts Derived from a Covalent Triazine Polymer.

Abstract: The construction of multi-heteroatom-doped metal-free carbon with a reversibly oxygen-involving electrocatalytic performance is highly desirable for rechargeable metal-air batteries. However, the conventional approach for doping heteroatoms into the carbon matrix remains a huge challenge owing to multistep postdoping procedures. Here, a self-templated carbonization strategy to prepare a nitrogen, phosphorus, and fluorine tri-doped carbon nanosphere (NPF-CNS) is developed, during which a heteroatom-enriched covalent triazine polymer serves as a "self-doping" precursor with C, N, P, and F elements simultaneously, avoiding the tedious and inefficient postdoping procedures. Introducing F enhances the electronic structure and surface wettability of the as-obtained catalyst, beneficial to improve the electrocatalytic performance. The optimized NPF-CNS catalyst exhibits a superb electrocatalytic oxygen reduction reaction (ORR) activity, long-term durability in pH-universal conditions as well as outstanding oxygen evolution reaction (OER) performance in an alkaline electrolyte. These superior ORR/OER bifunctional electrocatalytic activities are attributed to the predesigned heteroatom catalytic active sites and high specific surface areas of NPF-CNS. As a demonstration, a zinc-air battery using the NPF-CNS cathode displays a high peak power density of 144 mW cm-2 and great stability during 385 discharging/charging cycles, surpassing that of the commercial Pt/C catalyst.

Preparation of regenerated wool keratin films from wool keratin–ionic liquid solutions

Abstract: The regenerated wool keratin films were prepared from the wool keratin/ionic liquid solutions through water, methanol and ethanol as coagulation solvents in this article. It could be suggested from the results that [AMIM]+·Cl− ionic liquid has higher solubility for wool keratin fibers than [BMIM]+·Cl− ionic liquid. IR data showed the part of the disulfide bonds was broken during the dissolution. It could be seen from XRD data that the regenerated films exhibited a β-sheet structure and the disappearance of the α-helix structure. TGA curves indicated that the thermal stability of regenerated wool keratin films decreased slightly compared to nature wool fibers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013