Über das Schwingungsverhalten luftbereifter Fahrzeuge

Ohne Zusammenfassung Schlu? des Aufsatzes aus Heft 3 (1955) S. 87/95.     

Estimation using a multirate filter

This note presents both optimal and suboptimal filtering algorithms for estimating state variables based on measurements sampled at two different data rates. The optimal algorithm consists of two parallel Kalman filters; one processes the fast rate measurement and is of reduced-order, and the other processes the residuals from the first filter along with the slow rate measurement. This algorithm is used to design a suboptimal algorithm that has decreased computational requirements with only a small performance penalty.     

Polyacetylene photovoltaic devices

We present our study of polyacetylene photovoltaic junctions. Results indicate that barrier and depletion layer formation proceeds as if trans-(CH)_x were atraditional p-type semiconductor with a small surface state density. A (CH)_x: Al Schottky cell with junction internal conversion efficiency of 0.30% at low light level is reported. The effect of oxygen on the photosensitivity of (CH)_x based devices is also discussed.     

Vapor-solid-solid growth of crystalline silicon nanowires using anodic aluminum oxide template

Silicon nanowires (SiNWs) were grown at low temperatures close to metal silicon eutectic point on a silicon substrate using gold catalyst coupled with assistance of the aluminum anodic oxide template. Either a vapor-solid-solid (VSS) growth process below metal silicon eutectic temperature or a vapor-liquid-solid (VLS) process at slightly higher temperatures was observed. The transmission electron microscopy coupled with both the X-ray energy dispersive spectroscopy and the selected area electron diffraction was adopted to characterize the SiNWs. Although the mechanism triggering the VSS process is still not clear, both the geometric and morphological characteristics of the SiNWs grown by the VSS process are discussed and compared with the SiNWs grown by the VLS process. The VSS SiNWs have a much slower growth rate (less than 100 nm/h), a smaller and more uniform diameter (in the range of 15.22 nm) due to a much slower rate of silicon diffusion and much smaller amount of silicon (6.8 wt.%) dissolved in the solid nanocatalyst.     

Rigidity-Activity Relationships of bisQPC Scaffolds against Pathogenic Bacteria

Biscationic quaternary phosphonium compounds (bisQPCs) represent a promising class of antimicrobials, displaying potent activity against both Gram-negative and Gram-positive bacteria. In this study, we explored the effects of structural rigidity on the antimicrobial activity of QPC structures bearing a two-carbon linker between phosphonium groups, testing against a panel of six bacteria, including multiple strains harboring known disinfectant resistance mechanisms. Using simple alkylation reactions, 21 novel compounds were prepared, although alkene isomerization as well as an alkyne reduction were observed during the respective syntheses. The resulting bisQPC compounds showed strong biological activity, but were hampered by diminished solubility of their iodide salts. One compound (P2P-10,10 I) showed single-digit micromolar activity against the entire panel of bacteria. Overall, intriguing biological activity was observed, with less rigid structures displaying better efficacy against Gram-negative strains and more rigid structures demonstrating slightly increased efficacy against S. aureus strains.