The Pt magnetization depth profile at a single buried Pt/Co interface was investigated by x-ray resonant magnetic reflectivity measurements. The asymmetry as function of angle of incidence has been measured in the Pt L 3 -near-edge absorption region at two energies. Observed asymmetry ratios in the order of 0.5% are described on the basis of a magnetically modified Parratt algorithm. Excellent agreement between simulations and experiment was achieved for a Pt magnetic moment of 0.21 B at the rough interface followed by an exponential decay of the induced polarization within 1 nm.

Optical fiber-based sensors “embedded” in functionalized carbon structures (FCSs) and textile net structures (TNSs) based on alkaline-resistant glass are introduced for the purpose of structural health monitoring (SHM) of concrete-based structures. The design aims to monitor common SHM parameters such as strain and cracks while at the same time acting as a structural strengthening mechanism. The sensor performances of the two systems are characterized in situ using Mach-Zehnder interferometric (MZI) and optical attenuation measurement techniques, respectively. For this purpose, different FCS samples were subjected to varying elongation using a tensile testing machine by carefully incrementing the applied force, and good correlation between the applied force and measured length change was observed. For crack detection, the functionalized TNSs were embedded into a concrete block which was then exposed to varying load using the three-point flexural test until destruction. Promising results were observed, identifying that the location of the crack can be determined using the conventional optical time domain reflectometry (OTDR) technique. The embedded sensors thus evaluated show the value of the dual achievement of the schemes proposed in obtaining strain/crack measurement while being utilized as strengthening agents as well.

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Propylene-butene-1 copolymer (PBC) prepared with a titanium catalyst system was fractionated by temperature rising elution fractionation (TREF) over a temperature range of 5-80ЊC. PBC was shown to have a wide composition distribution ranging between 12-47 mol % of butene-1. Most of the fractions showed nearly the same crystallinity regardless of the butene-1 content. However, the solubility of the crystalline parts, which turned out to be the driving force for the fractionation, varied over the butene-1 content. Evidence that PBC shows isomorphism was obtained by the analysis of fractionated polymers, using 13 C nuclear magnetic resonance spectrometry, X-ray diffraction, differential scanning calorimetry, and gel permeation chromatography.

The paper presents an investigation into the durability of functionalized carbon structures (FCS) in a highly alkaline concrete environment. First, the suitability of optical fibers with different coatings-i.e., acrylate, polyimide, or carbon-for the FCS was investigated by subjecting fibers with different coatings to micro/macro bending and a 5% sodium hydroxide (NaOH) (pH 14) solution. Then, the complete FCS was also subjected to a 5% NaOH solution. Finally, the effects of spatial variation of the fiber embedded in the FCS and the bonding strength between the fiber and FCS was evaluated using different configurations -i.e., fiber integrated into FCS in a straight line and/or with offsets. All three coatings passed the micro/macro bending tests and show degradation after alkaline exposure, with the carbon coating showing least degradation. The FCS showed relative stability after exposure to 5% NaOH. The optimum bonding length between the optical fiber and the carbon filament was found to be ≥150 mm for adequate sensitivity.