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991.
992.
Duyao Zhang Shoujin Sun Dong Qiu Mark A. Gibson Matthew S. Dargusch Milan Brandt Ma Qian Mark Easton 《Advanced Engineering Materials》2018,20(5)
993.
Antony Jan Benjamin A. Reeves Yoeri van de Burgt Garrett J. Hayes Bruce M. Clemens 《Advanced Engineering Materials》2018,20(1)
994.
Helge Klippstein Hany Hassanin Alejandro Diaz De Cerio Sanchez Yahya Zweiri Lakmal Seneviratne 《Advanced Engineering Materials》2018,20(9)
995.
Microstructure and Processing of 3D Printed Tungsten Microlattices and Infiltrated W–Cu Composites
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Micha Calvo Adam E. Jakus Ramille N. Shah Ralph Spolenak David C. Dunand 《Advanced Engineering Materials》2018,20(9)
996.
Study of DNA Origami Dimerization and Dimer Dissociation Dynamics and of the Factors that Limit Dimerization
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Miran Liber Toma E. Tomov Roman Tsukanov Yaron Berger Mary Popov Dinesh C. Khara Eyal Nir 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(23)
Organizing DNA origami building blocks into higher order structures is essential for fabrication of large structurally and functionally diverse devices and molecular machines. Unfortunately, the yields of origami building block attachment reactions are typically not sufficient to allow programed assembly of DNA devices made from more than a few origami building blocks. To investigate possible reasons for these low yields, a detailed single‐molecule fluorescence study of the dynamics of rectangular origami dimerization and origami dimer dissociation reactions is conducted. Reactions kinetics and yields are investigated at different origami and ion concentrations, for different ion types, for different lengths of bridging strands, and for the “sticky end” and “weaving welding” attachment techniques. Dimerization yields are never higher than 86%, which is typical for such systems. Analysis of the dynamic data shows that the low yield cannot be explained by thermodynamic instability or structural imperfections of the origami constructs. Atomic force microscopy and gel electrophoresis evidence reveal self‐dimerization of the origami monomers, likely via blunt‐end interactions made possible by the presence of bridging strands. It is suggested that this mechanism is the major factor that inhibits correct dimerization and means to overcome it are discussed. 相似文献
997.
Asymmetrical Micro‐Supercapacitors: Laser‐Assisted Large‐Scale Fabrication of All‐Solid‐State Asymmetrical Micro‐Supercapacitor Array (Small 37/2018)
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998.
Laser‐Assisted Large‐Scale Fabrication of All‐Solid‐State Asymmetrical Micro‐Supercapacitor Array
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Jian Gao Changxiang Shao Shengxian Shao Feng Wan Chang Gao Yang Zhao Lan Jiang Liangti Qu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(37)
The micro‐supercapacitors are of great value for portable, flexible, and integrated electronic equipments. Here, the large‐scale and integrated asymmetrical micro‐supercapacitor (AMSC) array is fabricated in virtue of the laser direct writing and electrodeposition technology. The AMSC shows the ideal flexibility, high areal specific capacitance (21.8 mF cm?2), and good rate capability. Moreover, its energy density reaches 12.16 µW h cm?2, outperforming most micro‐supercapacitors reported previously. Meanwhile, large‐scale series‐connected AMSCs are integrated on the flexible substrates (e.g., indium tin oxide‐polyethylene terephthalate film), which can power a veriety of the commercial electronics. The combination of AMSCs array, solar cell, and electronic device proves the feasibility for practical application in the portable, flexible, and integrated electronic equipments. 相似文献
999.
Neng Li Shuai Huang Guodong Zhang Renyao Qin Wei Liu Huaping Xiong Gongqi Shi Jon Blackburn 《材料科学技术学报》2019,35(2):242-269
Recent efforts and advances in additive manufacturing (AM) on different types of new materials are presented and reviewed. Special attention is paid to the material design of cladding layers, the choice of feedstock materials, the metallurgical behavior and synthesis principle during the AM process, and the resulted microstructures and properties, as well as the relationship between these factors. Thereafter, the trend of development in the future is forecasted, including: Effects of the particles size and size distribution of powders; Approaches for producing fine microstructures; Opportunities for creating new materials by AM; Wide applications in reconditioning of damaged components; Challenges for deep understanding and applications of the AMed new materials. The idea of “Develop Materials” or “Create Materials” by AM is highlighted, but a series of scientific, technological and engineering problems remain to be solved in future. 相似文献
1000.
In this study, the crack propagation behaviors in the equiaxed and equiaxed-columnar grain regions of a heat-treated laser additive manufacturing (LAM) TC11 alloy with a special bi-modal microstructure are investigated. The results indicate that the alloy presents a special bi-modal microstructure that comprises a fork-like primary α (αp) phase surrounded by a secondary α colony (αs) in the β phase matrix after the heat treatment is completed. The samples demonstrate a fast crack growth rate with larger da/dN values through the equiaxed grain sample versus across the equiaxed-columnar grain sample at low ΔK values (<13.8). The differences that are observed between the crack propagation behaviors (in the crack initiation stage) of the samples can be mostly attributed to the different size and morphology of the αp lamellae and αs colony within the grains in the equiaxed and columnar grain regions rather than the grain boundaries. The cracks prefer to grow along the α/β boundary with a smooth propagation route and a fast propagation rate in the equiaxed grain region, where the αp and α clusters have a large size. However, in the columnar grain region, small and randomly distributed αp lamellae generate a zigzag-shaped propagation path with a reduction in the da/dN value. Additionally, the change in the size of the αp lamellae in the equiaxed grains (heat affected bands, HAB) is also observed to influence the propagation behavior of the crack during the crack initiation stage. 相似文献