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This study measures the x-ray-absorption spectra of a series of nanodiamond thin films with grain diameters ranging from 3.5 nm to 5 mm at the C K-edge using the sample drain current mode at room temperature. Resonance peaks resembling the C 1s core exciton are observed. The exciton state and conduction band edge are found to shift to higher energies with the decrease of the grain size indicative of the presence of the quantum confinement effect. [S0031-9007(99)

In this Article, we report the effect of postdeposition thermal treatment on reactively cosputtered copper tungstate (CuWO4) thin films and its impact on photoelectrochemical performances. This study indicates that CuWO4 films fabricated at 275 °C were amorphous and did not show significant photoresponse in 0.33 M H3PO4 electrolyte when irradiated with air mass 1.5Global simulated illumination. However, a major improvement in photoelectrochemical performance was observed in identical test conditions after a postdeposition treatment performed at 500 °C in pure argon for 8 h. Indeed, a photocurrent density of approximately 400 μA cm–2 at 1.6 V vs saturated calomel electrode was measured on the annealed CuWO4 samples. Subsequent X-ray diffraction analysis revealed a clear transformation of as-deposited amorphous thin films into a triclinic CuWO4 structure after the annealing step. The polycrystalline CuWO4 films exhibited n-type conductivity, an indirect band gap of 2.25 eV, and a flat-band potential of −0.35 V vs saturated calomel electrode.

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The initial stability at the time of implant placement is influenced by both the cortical bone thickness and the elastic modulus of trabecular bone; however, these parameters are not totally linearly correlated with ITV, PTV, and ISQ. The placement of an immediately loaded implant in cases with thin cortical bone and/or weak trabecular bone can induce extreme bone strains and may increase the risk of implant failure.

We report a direct determination of the specular scattering probability of acoustic phonons at a crystal boundary by observing the escape of incident coherent phonons from the coherent state during reflection. In the sub-THz frequency range where the phonon wavelength is much longer than the lattice constant, the acoustic phonon-interface interaction is found to agree well with the macroscopic theory on wave scattering from rough surfaces. This examination thus quantitatively verifies the dominant role of atomic-scale corrugations in the Kapitza anomaly observed at 1-10 K and further opens a new path to nondestructively estimate subnanoscale roughness of buried interfaces.

The molecular recoiling force stemming from nonequilibrium chain conformation was found to play a very important role in the dewetting stability of polymer thin films. Correct measurements and inclusion of this molecular force into thermodynamic consideration are crucial for analyzing dewetting phenomena and nanoscale polymer chain physics. This force was measured using a simple method based on contour relaxation at the incipient dewetting holes. The recoiling stress was found to increase dramatically with molecular weight and decreasing film thickness. The corresponding forces were calculated to be in the range from 9.0 to 28.2 mN/m, too large to be neglected when compared to the dispersive forces (approximately 10 mN/m) commonly operative in thin polymer films.