杂志纳米材料

还有通过静电纺丝（E-纺）大规模规模生产一些挑战。例如，工业化设备的成本是相对昂贵的，和随后的维修成本高。生产过程中的可靠性和稳定性也是最重要的挑战之一。有机溶剂的回收和溶剂的挥发不仅影响纳米纤维的质量，而且还造成了环境污染。在这项工作中，一个新的多针电子纺纱装置已经提出了规模化生产聚合物纳米纤维的。所述纺丝溶液通过针，以避免针堵塞的问题，这是从传统的多针电子纺丝不同的外表面设置。The successful preparation of thermoplastic polyurethane (TPU) nanofiber membrane with production rate ~50 g h^-1证明装置，它也可用于制备其它功能的纳米纤维，如聚偏氟乙烯（PVDF）和聚丙烯腈（PAN）的可行性。所制备的纳米纤维TPU纱布的特点。The average fiber diameter was 145.3 nm. The surface of the sample was found to be uniform, and the water contact angle was 138.9°. The sample had gas permeability of 1500 mm s^-1，优良的99.897％PM2.5去除率，和〜56％的光学透明度，这表明新的设备具有实际的应用前景。

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可生物降解的聚（乳酸）（PLA）的长丝已被广泛用于在熔融沉积成型（FDM）的3D印刷技术。然而，PLA具有较低的韧性和影响可印刷性和限制了它的工业应用低热阻。In this study, PLA was compounded with 0 to 40 wt% of poly(butylene adipate-co-terephthalate) (PBAT) and varied content of nano talc at 0 to 40 wt% in a twin screw extruder. The compounds were reextruded to filaments using a capillary rheometer. PLA/PBAT blends and their composite filaments were printed with a FDM 3D printing machine. Morphology, rheological behaviour, thermal characteristic, surface roughness, and mechanical property of 3D printing of the blends and the composites were investigated. Complex viscosity of the blends and the composites increased with increase of the PBAT and the nano talc contents. The incorporation of the nano talc enhanced crystallization temperature and reduced the coefficient of volume expansion of the composites. It was found that the PLA/PBAT blends and composites were excellent in both printability and dimension stability at PBAT content 10-30 wt% and nano talc up to 10 wt%. Interestingly, it was possible to print the composite filaments at an angle up to 75° during the overhang test without a supporter. From the vertical specimens, the surface roughness improved due to the incorporation of the nano talc. Tensile strength of the blends and the composites decreased, whereas elongation at break increased when the PBAT and the nano talc contents were increased. The reduction of tensile strength was attributed to agglomeration of the PBAT dispersed phase and less adhesion between the nano talc and the matrix. It can be noted that the composite 3D printing product showed superior elongation at break up to 410% by adding nano talc 1 wt%. This result suggests that the ductile 3D printable PLA/PBAT blend and the PLA/PBAT-nano talc composite products can be prepared, which shows potential for the commercialized scale.

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静电纺丝已被确认为对聚合物纳米纤维的制造中的有效技术。各种聚合物已成功静电纺丝成超细纤维在最近几年。这些生物聚合物静电纳米纤维具有潜在的伤口敷料的应用基于其独特的性质。在本文中，进行全面审查，提出到静电纺丝纳米纤维生物聚合物包括加工，结构与性能，特性和应用相关的研究和发展。与超细纤维的静电纺丝其处理条件的那些聚合物一起的信息已经总结在纸张。在伤口敷料电纺丝天然生物聚合物纤维的申请被具体地讨论。还讨论了关于技术的限制，研究的挑战，以及未来发展趋势等问题。

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本研究的目的是制备一种新的形状稳定的相变材料（PCM），棕榈酸硬脂酸/膨胀石墨（PA-SA / EG）PCM，潜热的热能。棕榈酸和硬脂酸的低共熔混合物中掺入的膨胀石墨（EG）。新颖的PCM的热性能和微观结构进行了研究。在复合PCM PA-SA的最佳质量比为约92.8％。DSC结果表明，所述新型的PCM具有适合相变温度（ ：55.18℃， ：54.91℃）和高的潜热（ ：176.2 J/g, ：175.6 J/g), and good thermal performance was maintained after 1500 times thermal cycling. The PA-SA binary eutectic mixture was uniformly distributed in the porous structure of EG, and the PCM did not leak even in molten state. EG had little effect on the thermal properties of the PA-SA binary eutectic mixture and remarkably improved the thermal conductivity of the composite PCMs. TGA test indicated that the composite PCM had nice thermostability in the range of operating temperature. Based on all these results, the PA-SA/EG composite PCM is a promising material for low-temperature thermal energy storage applications.

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的光电化学性能的增强银氧化锌@纳米线的实验和机理研究

本文重点研究的均匀的银纳米颗粒装饰的ZnO的光电化学（PEC）性能的提高（AG @ ZnO）的纳米线，其已经通过两步化学气相沉积法合成来制备的ZnO纳米线然后磁控溅射法来沉积银纳米颗粒。此外，我们分析了银@氧化锌纳米线的PEC行为的机制。在PEC特征表明银@氧化锌纳米线的电流密度增加比较于未修饰的ZnO纳米线。所述Ag-装饰的ZnO光电极的优化含量高达24.8的最大光电流密度 μACM^-2at 1 V vs. Ag/AgCl, which was almost four times than that of the unmodified ZnO photoelectrode. Based on the surface plasmon resonance (SPR), effect of Ag nanoparticles was enhanced PEC performance of the Ag@ZnO nanowires. Because SPR effect of Ag nanoparticles extended the light absorption and enhanced the separation efficiency of the photogenerated electron-hole pairs. The remarkable PEC properties offer metals-semiconductor compound nanostructures materials as a promising electron source for high current density applications.

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的纳米复合物的氧化锌/纤维素纳米晶体（氧化锌/ CNC控制器）被成功地通过使用用于吸附和亚甲基蓝（MB）的光催化降解低成本和绿色方法制备。CNC控制器已通过从越南分离纯纤维素用柠檬酸/盐酸水解反应衍生水椰树干。锌的影响²⁺在形态，微结构的离子浓度，和热性能以及在ZnO / CNC纳米复合物的光催化活性，详细进行了研究。Analyses of FTIR spectra, XRD, and SEM indicated that the ZnO nanocrystals with the size of 50 nm formed and loaded on the surface of CNC. Based on the DRS spectra and the nitrogen adsorption–desorption isotherms (BET) analysis, the absorption of ultraviolet light with a strong absorption band around 400 nm was found for all the ZnO/CNC nanohybrids, and the values of specific surface areas ( ）的材料可以通过改变锌的浓度比来控制²⁺离子和数控。在TGA分析表明，在ZnO装载样品（的ZnO / CNC）的热降解开始温度比纯CNC的更高。MB的去除效果表明这是不仅是CNC的吸附能力，而且通过ZnO的光催化活性贡献的结果。光催化效率显著取决于对ZnO负载的内容。The maximum degradation of MB was about 95% in 150 min for the ZnO/CNC-1.0 sample in which the concentration ratio of zinc-precursor Zn(NO₃）₂·6H₂O和CNC为1.0。

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