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Concrete surface coatings, either organic or inorganic, have long been used for the protection of reinforced concrete. The aim of the present work was to compare, in the presence of chloride ions, the performance of an acrylic emulsion and an inorganic coating, when the latter is or is not combined with an inorganic corrosion inhibitor. The behaviour of the inorganic coating was examined, as its use is increasing due to environmental reasons and it can be applied on concrete surfaces for the rehabilitation of old structures. Strain gauge (SG) technique, half‐cell potential measurements, mass loss and carbonation depth measurements, as well as chloride diffusion rate, revealed that the acrylic emulsion provides better protection for reinforcing steel in concrete than the inorganic coating. However, the combination of the inorganic coating with the corrosion inhibitor provides a higher level of protection against steel bar corrosion.

The purpose of this work was to investigate the possibilities for the exploitation of the powder by‐product of oxygen convertor slag from the ferronickel industry as pigment in anticorrosive non‐toxic paints. The chemical composition of the powder shows a large content of Fe₃O₄ and a high value of pH, two features favouring its use in anticorrosive paints. Paints with this powder, either unrefined or processed, as a pigment and chlorinated rubber resin were produced and tested by the following methods: half‐cell potential, mass loss, chloride diffusion and EIS. The results indicated that protection of steel was achieved to a satisfactory level, especially with the processed material.

The aim of the present work was to compare the performance of two coating systems applied on steel specimens. The first of them demands sandblasting pretreatment of the metal surface while the second one, which does not need it, leads to rust transformation. These systems were examined in three corrosive environments i.e. a geothermal fluid of low enthalpy, a 3.5 wt per cent NaCl solution and a 5wt per cent NaCl in a salt spray cabinet. The anticorrosive capability of the two coating systems was evaluated at predetermined exposure times by mass loss measurements of the steel substrate, by potentiodynamic polarization curves and by the half‐cell potential time evolution. Visual examination of the degree of rusting and blistering was also carried out. The results indicate that both coating systems exhibit almost similar protective behavior under the same conditions of pretreatment. In all cases, the corrosion rate increases with the increase of the surface roughness.

A number of applications selected with variations of factors affecting the corrosion of mortar steel reinforcements are discussed in this paper. Corrosion estimation by means of a strain gauge (SG) technique was used in several cases to confirm the validity of the method. The efficiency of corrosion inhibitors, the protection offered by the addition of minerals, the curing time influence, and the corrosion resistance of various steel types can be estimated by means of the short term SG test technique. Good correlations were found in all cases of application between the corrosion rates computed from SG technique and the mass loss data. Additionally, the method was applied for swelling measurements of mortar specimens caused by the degradation of FRP reinforcements in the corrosive environments.

The use of coatings (organic and inorganic) for the protection of reinforced concrete is widespread. The advantages of inorganic coatings are that they are stable in UV‐radiation, non‐combustible, do not foul and have a microcrystalline texture, while organic coatings have the advantage of low permeability of carbon dioxide, sulphur dioxide and water. The aim of the present work was to compare, in the presence of chloride ions, the performance of an acrylic dispersion and a silicate coating, when the latter was or was not combined with a corrosion inhibitor (N‐N’‐dimethylaminoethanol). The behaviour of the silicate coating was examined as its use is increasing due to environmental reasons and as it can be applied for the rehabilitation of old structures. Half‐cell potential measurements, mass loss and carbonation depth measurements, as well as chloride diffusion rate revealed that the acrylic dispersion provides better protection of reinforcing steel in concrete than the silicate coating, but the combination of the silicate coating with the corrosion inhibitor provides the best level of concrete protection.

A brief presentation of a laboratory technique with strain gauges (SG) detecting steel rebars corrosion in mortar specimens is given. The comparison of the application results obtained in specimens containing corrosion inhibitors is discussed in this paper. The present technique is based on the phenomena of tension state, in which the mortar mass comes near the rebar area, during the formation of corrosion products. SG embedded in reinforcing mortar specimens during casting monitor the internal stresses. Mortar specimens with admixtures and corrosion inhibitors, immersed in a 3.5 percent wt NaCl solution, were tested under impressed potential. Corrosion measurements through SG were correlated with those obtained from charge resistant transfer and compared with mass loss of the rebars. The test results obtained indicate that the SG technique, directly related to corrosion products, is suitable for the laboratory study of the influence of corrosion inhibitors in steel protection.

This paper aims to develop an electrochemical dechlorination method for large objects in a short time, which were for a long time in the sea. Traditionally, in conservation, chlorides are extracted from marine iron artifacts using complete immersion of those objects in alkaline solutions with or without electrolysis. However, these techniques are time-consuming and very costly, especially when applied to large marine artifacts such as cannons and anchors.

An appropriate sponge was chosen based on resistance to NaOH and the rate of exacted chlorides. Application of electrochemical dechlorination in situ and removal of chloride were measured by the scanning electron microscope (SEM)-EDAX method on the corrosion products and by titration of the electrolysis solution. X-ray diffraction (XRD) method is used for identification of corrosion products before and after application of electrochemical chloride extraction.

The electrochemical chloride extraction (ECE) method is applied against the corrosion of reinforced concrete. From the authors’ research, it is obvious that ECE can successfully extract chlorides from dried large metallic objects exported from the sea. The method of ECE removes the majority of chlorides from the metal during conservation treatment so that the application of organic coating will allow the object to remain stable over a long period.

A new methodology was developed for dechlorination of metallic objects exported from the sea in a short time and thus the consumption of chemical reagents was cut down.

This paper aims to present results of an experimental investigation on a series of scaled reinforced concrete column elements which were subjected to chloride exposure under accelerated conditions under a concurrent service axial load, over a period. In the presence of an axial load, directed microcracks of increasing density and width are introduced in the concrete mass, depending on the axial load level. Such cracks are believed to enhance the intrusion rate of chlorides in the concrete, relative to what is obtained in the normally performed unloaded specimen tests.

Eighteen column specimens were tested over two chloride exposure periods, of duration up to a maximum of six months. Three different service axial load levels were considered, namely, none, 22 per cent and 43 per cent of the normalized axial load capacity of the columns.

The results indicate that the specimens loaded to the higher axial load, which closely resembles actual service situation of such type of elements, exhibited up to ten times faster rates of induced current flow under a constant applied voltage of 500 mV, compared to the unloaded and less loaded specimens.

It is proven that the presence of axial load influences the rate of chloride ingress in columns and, therefore, should be taken into account in estimating the concrete cover of such elements in durability design.

The influence of axial loading on corrosion rate has not been considered in published experimental and analytical studies of chloride ingression. These studies have typically so far considered the accelerated corrosion of unloaded column specimens.

Social scientists often speculate that both acculturation and socioeconomic status are factors that may explain differences in the body weight between Mexican Americans and whites and between Mexican Americans and Mexican immigrants, yet prior research has not explicitly theorized and tested the pathways that lead both of these upstream factors to contribute to ethnic/nativity disparities in weight. We make this contribution to the literature by developing a conceptual model drawing from Glass and McAtee’s (2006) risk regulation framework. We test this model by analyzing data from the 1999–2012 National Health and Nutrition Examination Survey (NHANES). Our conceptual model treats acculturation and socioeconomic status as risk regulators, or social factors that place individuals in positions where they are at risk for health risk behaviors that negatively influence health outcomes. We specifically argue that acculturation and low socioeconomic status contribute to less healthy diets, lower physical activity, and chronic stress, which then increases the risk of weight gain. We further contend that pathways from ethnicity/nativity and through acculturation and socioeconomic status likely explain disparities in weight gain between Mexican Americans and whites and between Mexican immigrants and whites. Study results largely support our conceptual model and have implications for thinking about solutions for reducing ethnic/nativity disparities in weight.

The corrosion resistance of composite nickel electrodeposits with alumina embedded in the nickel matrix prepared in sulfate and chloride bath has been studied. As corrosion environment salt spray and nitric acid solution have been tested. The chloride type of deposits were more resistant in the corrosive environments studied than the sulfate ones. The structure as a consequence of the preparation conditions affect the corrosion resistance behavior of the deposits. The composite deposits with aluminium oxide exhibited a higher corrosion resistance in all tested conditions.