In this work, non-linear ultrasonic wave techniques have been used to detect the onset of micro-cracking due to steel corrosion in model reinforced concrete elements. The specimens were of prismatic shape with a single steel rebar. The corrosion was forced by admixing an appropriate amount of sodium chloride at the moment of preparing the concrete mix, and by the application of an electric field, using a constant current density power source, and making the steel rebar work as the anode, and an external counter-electrode as the cathode. The preliminary results indicate that the onset of cracking seems to be accompanied by the appearance of higher-harmonic generation at the output signal (harmonic distortion), when the system is excited by the means of an ultrasound wave with a burst central frequency. Other phenomena related to the micro-cracks induced by corrosion, such is the parametric generation with respect to the fundamental amplitude, have not been observed until now.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6427332PMC
http://dx.doi.org/10.3390/ma12050813DOI Listing

Publication Analysis

Top Keywords

non-linear ultrasonic
8
techniques detect
8
steel corrosion
8
reinforced concrete
8
steel rebar
8
ultrasonic techniques
4
detect cracks
4
steel
4
cracks steel
4
corrosion
4

Similar Publications

A new strategy for modelling sonochemical reactors: Coupling of the non-linear Louisnard model with mass and heat transport equations with applications to cavitating viscous fluids.

Ultrason Sonochem

October 2024

Department of Chemical Engineering, Process Engineering for Sustainable Systems, KU Leuven, Celestijnenlaan 200F, 3001 Heverlee, Belgium. Electronic address:

In this work, novel numerical models were developed and validated to offer new strategies in modelling sonochemical reactors. More specifically, in our original approach the non-linear Louisnard model was coupled with heat and mass transport equations to predict gradients in temperature and species concentration in a sonicated reactor. Additionally, a new operating window was investigated by modelling mixtures of increasing viscosity on both micro- and macroscale sonochemical effects.

View Article and Find Full Text PDF

This research work focuses on investigating the propagation of ultrasonic waves, which propagate mechanical vibrations of molecules or particles inside materials. Ultrasound imaging is extensively used and deeply rooted in the medical field. The key technologies that form the basis for many different uses in the area include transducers, contrast agents, pulse compression, beam shaping, tissue harmonic imaging, techniques for measuring blood flow and tissue motion, and three-dimensional imaging.

View Article and Find Full Text PDF

A Bioengineered Cathepsin B-sensitive Gas Vesicle Nanosystem That Responds With Increased Gray-level Intensity of Ultrasound Biomicroscopic Images.

Ultrasound Med Biol

January 2025

Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Post-Graduate Program in Surgical Sciences, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil. Electronic address:

Article Synopsis
  • The study focused on enhancing the interaction between modified gas vesicles (GVs) and the protease cathepsin B (CTSB) to analyze their ultrasound signals.
  • Researchers genetically engineered a protein (GvpC) to include a cleavage site for CTSB, expressed it in bacteria, and created modified GVs (GV*) for testing.
  • Results showed a significant increase in ultrasound signal intensity when the modified GVs interacted with CTSB, indicating that these GVs could serve as effective biosensors for detecting protease activity in tissues.
View Article and Find Full Text PDF

Preparation and characterization of oat hulls-filled-sodium alginate biocomposite microbeads for the effective adsorption of toxic methylene blue dye.

Int J Biol Macromol

November 2024

Department of Chemistry, Faculty of Arts & Sciences, Yildiz Technical University, Esenler, Istanbul 34220, Turkey. Electronic address:

In this work, the performance of oat hull-filled sodium alginate (SA-O) biocomposite microbeads in the adsorptive removal of methylene blue (MB) dye was examined. First, oat hulls were pulverized and biocomposite gels containing different weight ratios of oat hulls (10 %, 20 %, and 30 %, concerning the SA amount) were prepared by dispersing them in SA solution by ultrasonic homogenization method. Finally, gels were cross-linked by dropping into a 2 % CaCl solution.

View Article and Find Full Text PDF

Inter-visit and inter-reader reproducibility of multi-parametric diffusion-weighted MR imaging in longitudinally imaged patients with metabolic dysfunction-associated fatty liver disease and healthy volunteers.

Magn Reson Imaging

November 2024

Department of Radiology, Radiation Oncology and Nuclear Medicine, Université de Montréal, Montréal, Canada; Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada; Institute of Biomedical Engineering, Université de Montréal, Montréal, Canada. Electronic address:

Background: Despite the widespread use of diffusion-weighted imaging (DWI) in metabolic dysfunction-associated fatty liver disease (MAFLD), MRI acquisition and quantification techniques vary in the literature suggesting the need for established and reproducible protocols. The goal of this study was to assess inter-visit and inter-reader reproducibility of DWI- and IVIM-derived parameters in patients with MAFLD and healthy volunteers using extensive sampling of the "fast" compartment, non-rigid registration, and exclusion voxels with poor fit quality.

Methods: From June 2019 to April 2023, 31 subjects (20 patients with biopsy-proven MAFLD and 11 healthy volunteers) were included in this IRB-approved study.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!