In this letter, we report a one-step templating synthetic strategy to prepare aligned TiO2 nanotube and nanowire arrays on Si substrate from a solution at ambient temperature. The deposition of TiO2 and the selective-etching of the ZnO template proceeded at the same time through the careful control of process parameters. The different thickness of TiO2 sheaths, leading to the formation of nanotubes or nanorods, can be precisely controlled by the deposition time. The idea of selective etching and deposition is applicable to other oxide materials, and such a facile method is expected to find widespread applications.

A series of full-scale shaking table tests was conducted for a full-scale 21-story steel building frame subjected to a series of long-period, long-duration ground motions. The specimen consisted of a four-story, two-span by one-bay steel moment frame and an equivalent system. The frame portion was to present the lower four stories and the equivalent system was to simulate the remaining stories of the 21-story building. Major observations obtained from the test show that maximum drifts are smaller than 0.5% and 1.0% under minor and major earthquake loadings, respectively. Cyclic inelastic loading finally caused several fractures at the bottom flanges of beam ends. Shop weld connections show better cumulative deformation capacity than field weld ones. Story hysteresis behaviors remained stable and no severe strength deterioration occurred after connections fractured.

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