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The purpose of this paper is to study the corrosion of carbon steel without coating and when protected using three different hybrid coatings, i.e. a bi‐component polyurethane with nano‐particles of SiO₂ with and without sacrificial anode particles, and a mono‐component polyurethane with SiO₂ particles.

In this investigation three different nano‐structured coatings are developed and applied to steel substrates and then tested for their corrosion resistance (defined as “R_n”), under a very aggressive medium (pH=1.5) in a dynamic system (loop reactor). Their performance is evaluated using an electrochemical noise (EN) resistance technique. The electrodes are connected to a potentiostat and measurements are recorded as per the EN technique over a 2,048 s duration at 0, 24, and 48 h intervals. Scanning electron microscopy (SEM) are obtained before and after the corrosion trials to characterize the control and the different coating systems.

The results show that a bicomponent coating, made up of alkyd resin and silica nanoparticles demonstrated the best performance, whereas the coating formed by SiO₂ nanoparticles and polyurethane resin showed relatively low corrosion resistance. The inclusion of zinc nanoparticles in a third coating as sacrificial nano‐anodes led to segregation and resulted in moderate corrosion resistance. These results are confirmed by SEM observations.

The results obtained in this paper provide an insight to the understanding of the anticorrosion properties of three different hybrid coatings in a dynamic system (loop reactor).

The purpose of this paper is to report a study of microbiological influenced corrosion (MIC) of copper due to bacteria strains isolated from potable water pipes and oxidation lagoons using electrochemical noise (EN) analysis and scanning electron microscopy (SEM).

Bacteria strains isolated from copper surfaces of potable water pipes and from oxidation lagoons were identified, based on the 16S rDNA gene sequence analysis. Corrosion studies were undertaken over a period of six weeks, placing copper electrodes inside an LB culture media with and without bacteria. The corrosion resistance was obtained using EN analysis. In all the cases, the corrosion type was identified. SEM images of the copper electrodes were taken to evaluate the surface condition.

The bacteria strains identified were: Pantoea agglomerans, Alcaligenes faecalis, Bacillus cereus, Brucellaceae bacterium, Enterobacter cloacae, Delftia tsuruhatensis, and Pseudochrobactrum asaccharolyticum. EN analysis gave noise resistance values in the range 1,036‐5,040 Ωcm² for the control samples and in the range of 2,336‐22,573 Ωcm² for samples that had been inoculated with bacteria. It was found that a decrease in the rate of corrosion took place due to the development of a biofilm by the microorganisms on the copper surface. SEM images corroborated the presence of the biofilm on the copper electrodes.

The isolated bacteria strain reduced the rate of corrosion on the copper electrodes, as shown by the SEM images and EN analysis results, due to the formation of a biofilm that can act as an anticorrosive coating.

Even though MIC is a known phenomenon, it has not been reported that isolated bacteria strains can reduce corrosion on the surface of copper potable water pipes and in oxidation lagoons.

This study seeks to assess the impact of three factors related to graduates’ situation in the labor market on their satisfaction with university education. The dimensions are: (1) the gender of the graduates; (2) the institutional features of the institution attended, such as the selectivity of the university, and (3) the work experiences of young graduates once employed.

Responses from a sample of 718 graduates from 11 Chilean universities surveyed in 2021 were used to estimate the association between sociodemographic and institutional characteristics and satisfaction. The data analysis was carried out in two steps. First, nonlinear principal component analysis (PCA) assessed the variance shared by the three ordinal variables measuring satisfaction. In the second step, ordinary least squares (OLS) regression analysis assessed the relative contribution of the independent variables to scores on the satisfaction variable.

The main results emphasize the relevance of two main influences on satisfaction with their university education. These were the selectivity of the university and the graduates’ experiences in the labor market. Graduates from the most selective universities tend to show a higher level of satisfaction with their university education. Satisfaction is also highest among those graduates who rapidly entered the workforce and secured employment closely aligned with their degree.

This is the first study in Chile on the satisfaction of graduates conducted in a representative number of universities.

Mesquite pods offer a high nutritional content; A flour can be produced from them; nevertheless, the moisture content makes the milling process difficult. Then, before the milling operation a drying process must be implemented, but drying technology must be studied in order to characterise the process and identify the effect of drying temperature on the magnitude of drying rate.

Prosopis Laevigata pods were collected in Oaxaca (Southern of Mexico) and they were dried. Three stages of maturity were identified and pods in the stage three of maturity were dried by forced convection. The internal structure of the pods was analyzed by scanning electron microscopy (SEM). The pods were dried in a tunnel dryer at 40, 50, 60 and 70° C, 10% relative humidity and air velocity of 2.6 m/s. From experimental data, a lumped analysis was conducted for drying.

We found that the internal microstructure of this material is a limiting factor for moisture migration. In order to reduce the moisture content in the pods, a minimum air temperature of 60° C must be applied. The characteristic drying curve shows a good agreement with the experimental drying kinetics. The nutritional composition (carbohydrates, sugar and protein) of pods reveals important applications for the food industry.

The mesquite pods are important ethnic foods. In order to obtain flour, the drying of pods is mandatory. Drying must be applied in stage three of maturity which can be identified based on color changes and moisture content. The moisture content affects the performance of milling operation, then a minimum drying temperature of 60° C and low relative humidity must be applied. SEM images show the complex microstructure of the pods which hinders the moisture diffusion. The drying characteristic curve was deduced for the first time; it helps to understand the drying behavior of pods. The chemical composition of mesquite pods reveals interesting applications for the food industry. The methodology for drying is useful for researchers and producers.

Mezquite pods is an interesting ethnic food for people with celiac disease. This is the first time a research paper describes the drying process at detail. The SEM images, the convective drying operation and the characteristic curve are presented for the first time. The information will be useful for the industry and academia.

This chapter analyses, from the perspective of inclusion, the possibilities of participation for families in basic education schools in Mexico. Based on the analysis of articles published between 2012 and 2022, complemented by an analysis of normative instruments, the main patterns related to policies, practices and cultures were explored. The outcomes highlight a lack of recognition and appreciation of the diversity of families, restricted spaces and forms for their participation and cultural patterns that hinder their inclusion. The bases to favour inclusion are recognised and four key axes are proposed for its strengthening.

The design narrative details how the authors systematically and concretely adapted the design of afterschool club for children and pre-service teachers to respond to the increasingly explicit racism in US political discourse that fueled Trump’s election and coinciding forms of evading race.

The purpose of this paper is to present a design narrative focused on tensions around evading race in our after-school program for predominantly Latinx children and White pre-service teachers; how the authors re-mediated the material, ideational and relational resources of the program to address the tension; and the effects of our re-mediation on the adaptation of the program and how this shaped pre-service teachers’ engagement with children’s racialized experiences.

Re-mediating the design of ideational, relational, and material resources in the afterschool club allowed the designers to address how racial ideologies of color evasiveness limited opportunities for trust and mutual learning between the predominantly White preservice teachers and Latinx children.

The paper describes how concerns with equity emerged and were addressed in a program in a particular place and time for particular people. It offers a systematic view into the inner-workings of designing for equity and why people’s lived experiences, history and social practices around engaging with processes of racialization and power matter for the design of learning.

The design narrative suggests practical implications including the need to develop coursework and practicum experiences that support pre-service teachers’ and educators’ study of how power, enacted through racial ideologies of color evasiveness and other forms of epistemic violence, frames and materially impacts our interactions with children from non-dominant groups.

Two social implications from the design narrative include the following: the need to deepen the understandings of the past and present, proud and violent, histories of minoritized communities to organize consequential learning; and the need to recruit more students of color into the programs recognizing that it alone is not adequate for enacting educational justice.

As designers working toward equity, the authors must hold lightly onto their designs, be willing to let go of features that no longer serve the goals and develop new approaches that can help them achieve them. The authors must also attend seriously to the critiques offered by our youth-partners so that they can better support their learning and desires for the future.