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61.
Additive manufacturing technologies, generally grouped under the name of 3D printing, are experiencing an explosion of interest during the last few years. The possibility of fast prototyping enabled by 3D printing has been recognized as a crucial booster for device fabrication and general scientific advancements. In this review, attention is focused on the latest developments in the field of redox flow batteries which are, similar to other energy related devices, characterized by the recent adoption of 3D printing methods for the fabrication of key components. Whether simply to investigate flow phenomena, test new designs or fabricate final-product components with custom features, the use of 3D printing can critically drive this field of research towards better performing energy-storage systems. The latest and most representative examples of redox flow battery studies will be discussed, categorized in relation to the electrolyte used and whether the devices are employed in aqueous or non-aqueous applications. 相似文献
62.
3D打印制备陶瓷可以实现结构-材料设计一体化,为复杂形状陶瓷材料快速成型提供了新途径。但是传统的3D打印制备陶瓷是以陶瓷粉末或陶瓷颗粒为打印材料,存在陶瓷构件尺寸精度差、表面光洁度低和力学性能不佳等问题。近年来,以聚合物前驱体为打印材料,通过3D打印成型、高温裂解等工艺制备高性能陶瓷技术的出现为改善这些不足提供了新方法,成为3D打印陶瓷领域的研究热点。本文概述了聚合物前驱体3D打印制备高性能陶瓷的研究进展,重点阐述了本体聚合物前驱体、聚合物前驱体/光敏化合物、聚合物前驱体/巯基化合物、光敏基团改性聚合物前驱体、增强体/聚合物前驱体五种典型材料体系的研究现状,并对其今后的发展方向进行了展望。 相似文献
63.
Prof. Meng Su Feifei Qin Zeying Zhang Bingda Chen Qi Pan Dr. Zhandong Huang Zheren Cai Zhipeng Zhao Prof. Xiaotian Hu Prof. Dominique Derome Prof. Jan Carmeliet Prof. Yanlin Song 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14340-14346
A key issue of micro/nano devices is how to integrate micro/nanostructures with specified chemical components onto various curved surfaces. Hydrodynamic printing of micro/nanostructures on three-dimensional curved surfaces is achieved with a strategy that combines template-induced hydrodynamic printing and self-assembly of nanoparticles (NPs). Non-lithography flexible wall-shaped templates are replicated with microscale features by dicing a trench-shaped silicon wafer. Arising from the capillary pumped function between the template and curved substrates, NPs in the colloidal suspension self-assemble into close-packed micro/nanostructures without a gravity effect. Theoretical analysis with the lattice Boltzmann model reveals the fundamental principles of the hydrodynamic assembly process. Spiral linear structures achieved by two kinds of fluorescent NPs show non-interfering photoluminescence properties, while the waveguide and photoluminescence are confirmed in 3D curved space. The printed multiconstituent micro/nanostructures with single-NP resolution may serve as a general platform for optoelectronics beyond flat surfaces. 相似文献
64.
This review summarizes recent developments made in the incorporation of functional materials into organic polymer monoliths, together with new monolithic forms and formats, which enhance their application as supports and stationary phase materials for sample preparation and chromatographic separations. While polymer monoliths are well‐known supports for the separation of large molecules, recent developments have been made to improve their features for the separation of small molecules. The selectivity and performance of organic polymer monoliths has been improved by the incorporation of different materials, such as metal‐organic frameworks, covalent organic frameworks, or other types of nanostructured materials (carbon nanohorns, nanodiamonds, polyoxometalates, layered double hydroxides, or attapulgite). The surface area of polymer monoliths has been significantly increased by polymer hypercrosslinking, resulting in increased efficiency when applied to the separation of small molecules. In addition, recent exploration of less conventional supports for casting polymer monoliths, including photonic fibres and 3D printed materials, has opened new avenues for the applications of polymer monoliths in the field of separation science. Recent developments made in these topics are covered, focusing on the strategies followed by the authors to prepare the polymer monoliths and the effect of these modifications on the developed analytical applications. 相似文献
65.
Feng Li Melisa Rodas Ceballos Sepideh Keshan Balavandy Jingxi Fan Mohammad Mahdi Khataei Yadollah Yamini Fernando Maya 《Journal of separation science》2020,43(9-10):1854-1866
In the last 5 years, additive manufacturing (three‐dimensional printing) has emerged as a highly valuable technology to advance the field of analytical sample preparation. Three‐dimensional printing enabled the cost‐effective and rapid fabrication of devices for sample preparation, especially in flow‐based mode, opening new possibilities for the development of automated analytical methods. Recent advances involve membrane‐based three‐dimensional printed separation devices fabricated by print‐pause‐print and multi‐material three‐dimensional printing, or improved three‐dimensional printed holders for solid‐phase extraction containing sorbent bead packings, extraction disks, fibers, and magnetic particles. Other recent developments rely on the direct three‐dimensional printing of extraction sorbents, the functionalization of commercial three‐dimensional printable resins, or the coating of three‐dimensional printed devices with functional micro/nanomaterials. In addition, improved devices for liquid–liquid extraction such as extraction chambers, or phase separators are opening new possibilities for analytical method development combined with high‐performance liquid chromatography. The present review outlines the current state‐of‐the‐art of three‐dimensional printing in analytical sample preparation. 相似文献
66.
Carlos M.S. Vicente Toms S. Martins Marco Leite Antnio Ribeiro Luís Reis 《先进技术聚合物》2020,31(3):501-507
This work aims to determine the influence of fused deposition modeling (FDM) printing parameters on the mechanical properties of parts fabricated on an Ultimaker2 printer with acrylonitrile butadiene styrene (ABS). The effect of several parameters such as interlayer cooling time (ILCT), nozzle diameter, infill density, raster angle and layer thickness on the ultimate tensile strength, yield strength, and elastic modulus of produced parts was evaluated. Two independent studies were conducted: a first study dedicated to the ILCT and a second study where the influence of other parameters was evaluated through a design of experiments (DoE) approach. Both studies were carried out through the execution of standard tensile tests. The statistical analysis of tensile tests results was processed with the ANOVA methodology. The obtained results indicate that a reduced ILCT improves the tensile strength of parts. It is shown that nozzle diameter and infill density are the parameters that most influence the mechanical properties of ABS, with the upper range selected values improving the studied mechanical properties. The raster angle configuration of (?45o/45o) benefits UTS and yield strength of ABS samples. Interactions of nozzle diameter on layer thickness were detected. It was observed that smaller layer thickness promotes a higher elastic modulus and UTS; however, for thinner layers (0.06‐0.10 mm), no significant differences were found on strength of samples due to potential high distortion levels. 相似文献
67.
68.
建立了同时测定紫外光固化(UV)胶印油墨中27种溶剂残留(挥发性有机化合物,VOCs)的顶空-气相色谱-质谱联用(HS-GC-MS)法。将UV胶印油墨样品模拟印刷制成一定面积、厚度的试样,在紫外灯下烘烤1 min,经80℃、45 min静态顶空后,通过VOC专用毛细管柱分离和质谱检测,外标法定量。27种VOCs均呈现良好的线性关系,相关系数(R2)均≥0.9950;方法的检出限(LODs,S/N=3)为0.001~0.310 mg/m2,定量限(LOQs,S/N=10)为0.003~0.920 mg/m2;样品的平均加标回收率为80%~108%,相对标准偏差(RSD)<6%(n=6)。该方法制样便捷,灵敏度高,精密度好,准确度高,将其应用于实际UV胶印油墨样品的检测,取得了良好效果。 相似文献
69.
3D打印金属材料研究进展 总被引:1,自引:0,他引:1
3D打印技术是快速原型制造技术的一种,也被称为增材制造技术,被誉为"第三次工业革命"的核心技术,其中金属3D打印被认为是将来制造业的主导方向.金属粉末材料是金属打印的物质基础,同时也是3D打印技术发展的突破点.综述了3D打印金属粉体材料的研究现状,重点介绍了钛合金、铝合金、不锈钢、高温合金和镁合金等5种金属粉体材料在3D打印技术中的应用,并对金属粉体材料的运用进行总结和展望. 相似文献
70.
以三羟甲基丙烷、间苯二甲酸、Cardura E10(E10)为原料合成聚酯树脂,探讨E10对聚酯树脂性能的影响;通过聚酯树脂、环氧树脂和氨基树脂制备丝网印刷涂料,研究环氧树脂用量和品种、功能性助剂对丝网印刷涂料性能的影响.工艺条件为m(E-44)/m(E-51)=2.33-4,w(H-201)=0.15%-0.2%,w(有机膨润土)=2.0%-4.0%,w(对甲苯磺酸)=3.0%-3.5%时,丝网印刷涂料150℃下烘干300 s,硬度为3 H,耐5%的HCl、H2SO4、NaOH和NaCl溶液7 d涂层不起泡、不脱落. 相似文献