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Thin films of amorphous iron and nickel have been prepared by low-temperature condensation in high vacuum, and a transmission electron diffraction study of these films has been undertaken. A radial distribution analysis of the patterns composed of diffuse halos has been carried out in order t o investigate the local atomic arrangement in amorphous iron and nickel. W ( r ) (= e(r)/po) experimentally derived has been compared with W ( r ) calculated from several structure models. Best resemblance in shape to the experimental W ( r ) has been obtained by W ( r ) calculated from a dense random packed structure, leading to the conclusion that the atomic arrangement in amorphous iron and nickel is, t o a good approximation, represented by the dense random packed structure.Dunne amorphe Eisen-und Nickelschichten wurden durch Verdampfung bei tiefen Temperaturen im Hochvakuum hergestellt und mit Elektronenbeugung untersucht. Eine Radialverteilungsanalyse der diffusen Beugungsdiagramme wurde durchgefuhrt, urn die Nahordnung der Atome in amorphem Eisen und Nickel zu untersuchen. Die gewonnene Radialverteilungsfunktion W ( r ) wird mit den aus verschiedenen Strukturmodellen berechneten W ( r ) verglichen. Die beste Ubereinstimmung wurde zwischen den experimentellen Kurven und den Kurven einer ungeordneten dichtgepackten Sttuktur gefunden und daraus wird geschlossen, daD die Nahordnung der Atome in amorphem Eisen und Nickel der ungeordneten dichtgepackten Struktur sehr iihnlich ist.

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Carbon nanowalls (CNWs), which are vertically oriented multi-layer graphene sheets, were employed in surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) measurements to detect low-molecular-weight organic compounds. CNWs substrates with widely different wall-to-wall distances from 142 to 467 nm were synthesized using a radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) system with nanosecond pulse biasing to a sample stage. When survival yield (SY) values of N-benzylpyridinium chloride (N-BP-Cl) were examined, which is commonly used to evaluate desorption/ionization efficiency, a narrower wall-to-wall distance presented a higher SY value. The highest SY value of 0.97 was realized at 4 mJ/cm2 for the highest-density CNWs with a wall-to-wall distance of 142 nm. The laser desorption/ionization effect of arginine, an amino acid, was also investigated. When CNWs with a narrower wall-to-wall distance were used, the signal-to-noise (SN) ratios of the arginine signals were increased, while the intensity ratios of fragment ions to arginine signals were suppressed. Therefore, the CNWs nanostructures are a powerful tool when used as a SALDI substrate for the highly efficient desorption/ionization of low-molecular-weight biomolecules.

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