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The lead-free piezoelectric ceramics 0.82(Bi 0:5 Na 0:5 )TiO 3 -0.15BaTiO 3 -0.03(Bi 0:5 Na 0:5 )(Mn 1=3 Nb 2=3 )O 3 (abbreviated as BNT-BT-BNMN) was prepared by a conventional process of ceramic engineering. The X-ray diffractometer (XRD) analysis showed that all compositions could form a single perovskite phase. The ceramics showed excellent piezoelectric properties with a coupling factor k t ¼ 41%, a mechanical quality factor Q m ¼ 500, a piezoelectric constant d 33 ¼ 110 pC/N, a relative permittivity " T 33 =" 0 ¼ 520, a dissipation factor tan ¼ 0:66%, a Curie point T c ¼ 260 C, and a density ¼ 5:5 g/cm 3 . The physical properties of the ceramics were superior to those of hard Pb(Zr,Ti)O 3 (PZT). The high-power characteristics of the ceramics were superior to those of hard PZT. A cylinder sample of lead-free ceramics was used to fabricate a bolt-clamped Langevin transducer (BLT) for application in the ultrasonic cleaner. The vibration velocity of BLT using the ceramics was higher than that of hard PZT under the same input power. The cleaning effect of an ultrasonic cleaner using the BLTs was very high and sufficiently good for commercial application.

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We have carried out a photoemission study using synchrotron radiation of dodecanethiolate-(DT-) passivated Au nanoparticles supported on the highly oriented pyrolytic graphite (HOPG) substrates. From detailed line-shape analyses of Au 4f core-level photoemission spectra of DT-passivated Au nanoparticles, it is found that Au 4f core-level spectra consist of the two components. We attribute these components to the inner Au atoms and surface Au atoms bonded to surface dodecanethiolates. From these results, we discuss the chemical states of the present DT-passivated Au nanoparticles.