Experimental Study of Mechanical Wave Propagation in Solidifying Cement-Based Composites.

In this paper, a new measurement procedure is presented as an experimental study. In this experimental study, a measurement system using the pass-through pulsed ultrasonic method was used. The pilot application of the measurement setup was to monitor mechanical wave changes during the solidification and hardening of fine-grained cement-based composites.

Non-Destructive Characterization of Cured-in-Place Pipe Defects.

Sewage and water networks are crucial infrastructures of modern urban society. The uninterrupted functionality of these networks is paramount, necessitating regular maintenance and rehabilitation. In densely populated urban areas, trenchless methods, particularly those employing cured-in-place pipe technology, have emerged as the most cost-efficient approach for network rehabilitation.

The Effect of Specimen Size on Acoustic Emission Parameters and Approximate Position of Defects Obtained during Destructive Testing of Cementitious and Alkali-Activated Degraded Fine-Grained Materials.

Two sizes of test samples were selected to investigate the effect of size on the level of degradation. The smaller test specimens had dimensions of 40 × 40 × 160 mm, and the larger ones had dimensions of 100 × 100 × 400 mm. Both sizes of test specimens were always made of the same mortar.

Monolayers of photosystem II on gold electrodes with enhanced sensor response--effect of porosity and protein layer arrangement.

Mass transport of the bulk of the analyte to the electrode and through the bioactive layer can be significantly improved by use of the nanoelectrode array and defined arrangement of protein film. This phenomenon has been studied by (i) atomic-force microscopy, (ii) electrochemical measurements of PSII activity, and (iii) digital simulations for an oriented monolayer of histidine-tagged photosystem II (PSII) immobilized on nitrilotriacetic acid (NTA)-modified gold electrodes. The output signal of the electrochemical biosensor is controlled by (i) mass transport from the bioactive layer to electrode and (ii) mass transport between the bulk of the analyte and the electrode.