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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.

The Waorani are an Amazonian indigenous nationality with a population of 4,000. They inhabit three provinces of Ecuador: Pastaza, Napo and Orellana, and their ancestral lands contain a wealth of natural resources, which attracts the onslaught of the processes of extractivism. Significant social and economic asymmetries have also arisen in the decades since first contact. It is in this context that the Waorani Women's Association was created in 2005. Its main purpose is to end deforestation and illegal hunting of species in Waorani territory by promoting initiatives such as the cultivation of organic cocoa and handicrafts to improve the economy of families and to diminish the reliance on the preponderant economic system of use and abuse of non-renewable resources. This chapter analyzes how the spirituality of the Waorani nationality, manifested by the women who work in cocoa farms and chambira palm crafts, combine syncretism and ancestral knowledge in their daily work. It also analyzes the change of spiritual identity from the first contact with the Summer Language Institute missionaries, and subsequent evangelical, Catholic, Jehovah's Witnesses and the Church of Latter-day Saints missions to their lands.

The objective of this chapter is to identify the key characteristics of Global Services businesses that will thrive and achieve success in the future. These factors are integrated into three main pillars, which we refer to as the Triple-Win. The first and most obvious pillar is technology as a tool. The second pillar is the design and sustainability of the business model, without which the previous factor would be merely a cost and not an investment. And last but not the least, there is the purpose which gives meaning to the proposal, focusing on the human being and their environment. The DIDPAGA business model sits at the intersection of these three elements.

The purpose of this paper is to compare the imaginaries of Generation Z inhabitants of heritage cities in the Mexican Bajio regarding their city of residence and the institutional imaginary of urban tourism.

A total of 186 students from five Mexican heritage cities completed an online questionnaire and participated in focus groups. The authors used a mixed approach with qualitative analysis for open-ended responses and a Kruskal Wallis test to measure attitudes towards tourism and its relationship to place attachment and intangible cultural heritage identification.

The results showed a strong relationship between place attachment and perception of tourism, but attitudes towards tourism varied among the cities, and San Juan del Río was an outlier. Among the categories of intangible cultural heritage, oral traditions showed the least agreement between youth and institutional imaginaries.

Few studies have considered Mexican youth and their imagery of the small/medium-sized city in which they live when it is promoted as an urban tourist destination.

Comparar los imaginarios de los habitantes de la Generación Z de las Ciudades Patrimonio del Bajío mexicano respecto a su ciudad de residencia y el imaginario institucional del turismo urbano.

Aplicamos un cuestionario a 186 estudiantes de cinco ciudades patrimonio mexicanas quienes además, participaron en grupos focales. Se utilizó un enfoque mixto con análisis cualitativo para las respuestas abiertas y una prueba de Kruskal Wallis para medir las actitudes hacia el turismo y su relación con el apego al lugar y la identificación del Patrimonio Cultural Inmaterial.

Los resultados mostraron una fuerte relación entre el apego al lugar y la percepción del turismo, pero las actitudes hacia el turismo variaron entre las ciudades siendo San Juan del Río un caso atípico. Entre las categorías del Patrimonio Cultural Inmaterial, las tradiciones orales mostraron la menor concordancia entre los jóvenes y los imaginarios turísticos institucionales.

Pocos estudios han considerado el imaginario de jóvenes mexicanos con respecto a ciudades pequeñas-medianas en las que viven, cuando éstas se promueven como destinos turísticos urbanos

This review discusses the concept of edible nanocoatings (ENCs), the biomaterials used in the coating matrices, techniques of coating development, applications, challenges and safety regulations associated with nanotechnology in food products. These ENCs are capable of imparting increased shelf life, improved appearance, better physiological qualities and bioactive potentials such as antimicrobial and antioxidant properties. ENCs can be developed using the layer-by-layer method which forms multiple alternative layers adhered together primarily by electrostatic interactions.

Various keywords such as edible coatings (ECs), safety aspects and nanocoatings were used to search the literature from Google Scholar, Research Gate, ScienceDirect, Springer Link, Taylor and Francis and PubMed. After searching enough literature, 113 articles and research papers were examined, which provides the updated overview of different aspects of edible nano-coatings.

Consumers today are very much aware of the food quality and its safety. They demand food products with longer shelf life, which are minimally processed with natural or no preservatives. ECs based on biopolymers is an alternative technique, which is biodegradable and can be consumed as such without posing any safety risks. The emergence of nanotechnology in food processing has provided new insights to develop ECs at the nanoscale with improved mechanical and barrier properties

ECs are beneficial to consumers and to the environment. ECs have generated significant attention over years as an alternative to fossil-based plastics, considering their renewable and biodegradable features

This paper aims to determine whether policy uncertainty caused by institutional decay in countries with populist rulers influences the internationalization decision of emerging market firms (EMFs).

The study used binary logit analysis on firms from Latin American countries undertaking cross-border greenfield investment projects.

The results suggest that internationalization decision is demotivated by policy uncertainty generated by populist chief executives and promoted by that of political parties.

This study uses populist rhetoric to describe policy uncertainty due to chief executives and ruling parties, which influences internationalization decision by increasing anticipated transaction costs. This inquiry identifies populism as a variable that influences EMFs to internationalize, while empirically testing the claim of theoretical scholarship that populism reconfigured the sociopolitical and institutional forces that shape the world’s business. This study further advances institutional theory by offering a fresh perspective on the influence of home instead of host-country institutions on the internationalization motivation of firms due to institutional decay caused by populist regimes.