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Angst UM, Rossi E, Boschmann Käthler C, Mannes D, Trtik P, Elsener B, Zhou Z, Strobl M. Chloride-induced corrosion of steel in concrete-insights from bimodal neutron and X-ray microtomography combined with ex-situ microscopy. Mater Struct 2024; 57:56. [PMID: 38601013 PMCID: PMC11001691 DOI: 10.1617/s11527-024-02337-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 03/19/2024] [Indexed: 04/12/2024]
Abstract
The steel-concrete interface (SCI) is known to play a major role in corrosion of steel in concrete, but a fundamental understanding is still lacking. One reason is that concrete's opacity complicates the study of internal processes. Here, we report on the application of bimodal X-ray and neutron microtomography as in-situ imaging techniques to elucidate the mechanism of steel corrosion in concrete. The study demonstrates that the segmentation of the specimen components of relevance-steel, cementitious matrix, aggregates, voids, corrosion products-obtained through bimodal X-ray and neutron imaging is more reliable than that based on the results of each of the two techniques separately. Further, we suggest the combination of tomographic in-situ imaging with ex-situ SEM analysis of targeted sections, selected based on the segmented tomograms. These in-situ and ex-situ characterization techniques were applied to study localized corrosion in a very early stage under laboratory chloride-exposure conditions, using reinforced concrete cores retrieved from a concrete bridge. Several interesting observations were made. First, the acquired images revealed the formation of several corrosion sites close to each other. Second, the morphology of the corrosion pits was relatively shallow. Finally, only about half of the total 31 corrosion initiation spots were in close proximity to interfacial macroscopic air voids, and > 90% of the more than 160 interfacial macroscopic air voids were free from corrosion. The findings have implications for the mechanistic understanding of corrosion of steel in concrete and suggest that multimodal in-situ imaging is a valuable technique for further related studies. Supplementary Information The online version contains supplementary material available at 10.1617/s11527-024-02337-7.
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Affiliation(s)
- Ueli M. Angst
- Institute for Building Materials, ETH Zurich, Zurich, Switzerland
| | - Emanuele Rossi
- Institute for Building Materials, ETH Zurich, Zurich, Switzerland
| | - Carolina Boschmann Käthler
- Institute for Building Materials, ETH Zurich, Zurich, Switzerland
- Hagerbach Test Gallery Ltd., VSH, Flums, Switzerland
| | - David Mannes
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut, Villigen, Switzerland
| | - Pavel Trtik
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut, Villigen, Switzerland
| | - Bernhard Elsener
- Institute for Building Materials, ETH Zurich, Zurich, Switzerland
| | - Zhou Zhou
- Department NPM2/RST, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Markus Strobl
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut, Villigen, Switzerland
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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Molloy J, Castro A, Götschi T, Schoeman B, Tchervenkov C, Tomic U, Hintermann B, Axhausen KW. The MOBIS dataset: a large GPS dataset of mobility behaviour in Switzerland. Transportation (Amst) 2022; 50:1-25. [PMID: 35757094 PMCID: PMC9212210 DOI: 10.1007/s11116-022-10299-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
This article presents the MOBIS dataset and underlying survey methods used in its collection. The MOBIS study was a nation-wide randomised controlled trial (RCT) of transport pricing in Switzerland, utilising a combination of postal recruitment, online surveys, and GPS tracking. 21,571 persons completed the first online survey, and 3680 persons completed 8 weeks of GPS tracking. Many continued tracking for over a year after the study was completed. In the field experiment, participants participated through the use of a GPS tracking app, Catch-my-Day, which logged their daily travel on different transport modes and imputed the trip segments and modes. The experiment lasted 8 weeks, bookended by two online surveys. After the first 4-week control phase, participants were split into two different treatment groups and a continued control group. An analysis of the survey participation shows that the technology is capable of supporting such an experiment on both Android and iOS, the two main mobile platforms. Significant differences in the engagement and attrition were observed between iOS and Android participants over the 8-week period. Finally, the attrition rate did not vary between treatment groups. This paper also reports on the wealth of data that are being made available for further research, which includes over 3 million trip stages and activities, labelled with transport mode and purpose respectively. Supplementary Information The online version contains supplementary material available at 10.1007/s11116-022-10299-4.
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Affiliation(s)
| | | | | | | | | | - Uros Tomic
- INE, Zurich University of Applied Sciences, Winterthur, Switzerland
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Curjuric I, Imboden M, Bridevaux PO, Gerbase MW, Haun M, Keidel D, Kumar A, Pons M, Rochat T, Schikowski T, Schindler C, von Eckardstein A, Kronenberg F, Probst-Hensch NM. Common SIRT1 variants modify the effect of abdominal adipose tissue on aging-related lung function decline. Age (Dordr) 2016; 38:52. [PMID: 27125385 PMCID: PMC5005914 DOI: 10.1007/s11357-016-9917-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/18/2016] [Indexed: 06/05/2023]
Abstract
Lung function is an independent predictor of mortality and serves as an aging marker in never smokers. The protein sirtuin-1 of gene SIRT1 has profound anti-inflammatory effects and regulates metabolic pathways. Its suggested longevity effects on lower organisms remain poorly studied in humans. In 1132 never smokers of the population-based SAPALDIA cohort, we investigated associations between single nucleotide polymorphisms (SNPs; rs730821, rs10997868, rs10823116) of SIRT1 and aging-related lung function decline over 11 years in terms of change in forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, and forced expiratory flow between 25 and 75 % of FVC (FEF25-75) using multiple linear regression models. Interactions between the SIRT1 SNPs and adiposity parameters (body mass index (BMI), its change and weight gain) were tested by including multiplicative interaction terms into the models. SIRT1 polymorphisms exhibited no main effects, but modified the association between obesity measures and FEV1/FVC and FEF25-75 decline (p = 0.009-0.046). Per risk allele, FEV1/FVC decline was accelerated up to -0.5 % (95 % CI -1.0 to 0 %) and -0.7 % (-1.3 to -0.2 %) over interquartile range increases in BMI (2.4 kg/m(2)) or weight (6.5 kg), respectively. For FEF25-75 decline, corresponding estimates were -57 mL/s (-117 to 4 mL/s) and -76 mL/s (-1429 to -9 mL/s). Interactions were not present in participants with genetically lowered C-reactive protein concentrations. Genetic variation in SIRT1 might therefore affect lung function and human longevity by modifying subclinical inflammation arising from abdominal adipose tissue.
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Grants
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Bundesamt für Umwelt
- Bundesamt für Gesundheit
- Bundesamt für Strassen
- Canton’s government of Aargau, Basel-Stadt, Basel-Land, Geneva, Luzern, Ticino, Valais, and Zürich
- Swiss Lung League
- Canton’s Lung League of Basel Stadt/ Basel Landschaft, Geneva, Ticino, Valais, Graubünden and Zurich
- Stiftung ehemals Bündner Heilstätten
- SUVA
- Freiwillige Akademische Gesellschaft
- UBS Wealth Foundation
- Talecris Biotherapeutics GmbH
- Abbott Diagnostics
- European Commission
- Wellcome Trust
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Affiliation(s)
- Ivan Curjuric
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
| | - Medea Imboden
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Margaret W Gerbase
- Division of Pulmonary Medicine, University Hospitals, Geneva, Switzerland
| | - Margot Haun
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Dirk Keidel
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Ashish Kumar
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Marco Pons
- Division of Pulmonary Medicine, Regional Hospital of Lugano, Lugano, Switzerland
| | - Thierry Rochat
- Division of Pulmonary Medicine, University Hospitals, Geneva, Switzerland
| | - Tamara Schikowski
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Christian Schindler
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Florian Kronenberg
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Nicole M Probst-Hensch
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland
- University of Basel, Basel, Switzerland
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