The nanostructured assembly of porphyrin and gold nano-particles exhibits distinct enhancement of photocurrents from porphyrin in the longer wavelength region, where the localized plasmon resonance was responsible

Gold nanoparticle films with different particles sizes (35 ( 5, 15 ( 1 nm) and agglomerated states were prepared on glass substrates, by salting-out the colloidal solutions with NaClO 4 or NaOH. An ethanol solution of rhodamine 6G was cast on the gold nanoparticle film and the surface-enhanced Raman scattering (SERS) spectrum was measured. We found that the intensity of the SERS signal was higher for the film with larger particles and that the film prepared from NaClO 4 gave higher SERS signals than that prepared from NaOH. Considerable coalescence of larger gold nanoparticles was quite effective for obtaining larger SERS signals.The SERS enhancement factor was estimated to be ∼10 8 for the film prepared from NaClO 4 .

We report on the first successful output of electrons directly from photosystem I (PSI) of thermophilic cyanobacteria to the gate of a field-effect transistor (FET) by bypassing electron flow via a newly designed molecular wire, i.e., artificial vitamin K(1), and a gold nanoparticle; in short, this newly manufactured photosensor employs a bio-functional unit as the core of the device. Photo-electrons generated by the irradiation of molecular complexes composed of reconstituted PSI on the gate were found to control the FET. This PSI-bio-photosensor can be used to interpret gradation in images. This PSI-FET system is moreover sufficiently stable for use exceeding a period of 1 year.

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A new non-destructive evaluation technique to detect cracks emanating from the inner surface (inner cracks) of a high-pressure hydrogen storage cylinder was developed by means of mechanoluminescence (ML) sensor consisting of SrAl 2 O 4 :EuML material and epoxy resin. To visualize the inner crack,a sheet ML sensor was attached onto the outer surface of the storage cylinder subjected to hydraulic pressure cycling with the maximum pressure of 45 MPa. The ML pattern was changed with an increase in the cycle number and the ML sensor could visualize the inner crack. The stress analysis by the finite element method clarified that the ML sensor provided unique equivalent strain distribution associated with stress concentration at the crack tip, i.e. the distance between two points having high equivalent strains was inversely proportional to the crack depth;consequently, the growth behavior of the inner crack was non-destructively quantified with the ML sensor attached on the outer surface.