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Thin wall and plate structure is an important application of ultra high performance concrete (UHPC). The reduction in thickness of the structure will affect the orientation of steel fiber and its mechanical properties, such as bending properties. The bending failure of UHPC sheet with thickness from 5 mm to 50 mm was studied, and the change in the orientation of steel fiber caused by the thickness was also analyzed by three dimensional video microscope and image method. It is found that failure load borne increases rapidly when the thickness of sheet is larger than 20mm. Bending strength, however, increases with the decrease in the thickness of the sheet, and the orientation (along the length of sample) of fiber is gradually enhanced, especially for 5-10 mm sheet. The variation of bending strength mainly depends on the orientation of steel fiber and thickness factor, and the latter has greater effect on bending strength of ultra thin plate. [ABSTRACT FROM AUTHOR]

Coordination self‐assemblies have attracted more and more attentions from chemists because of their beautiful structures and wide applications, and a number of excellent reviews that focus on either synthesis or application have been published. This paper will hightlight how to controllablly construct supramolecular assemblies based on flexibility of ligands driven by different external stimuli. Herein, not only various discrete metal‐organic aggregates including M2L2 type metallocycles, M2L4/M2L6/M3L2/M6L4/M6L8 type metallocages have been prepared, but also many well‐organized ensembles based on such new‐formed discrete aggretates have been further assembled driven by suitable external stimuli. Also, controllable self‐assembly processes accompanied with structure changes have been developed. It is expected that this paper will provide a potential strategy for developing novel coordination assemblies that can be comparable to biomacromolecules from organism. [ABSTRACT FROM AUTHOR]