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The purpose of this study was to evaluate the possibility of using conductive polymers such as polyaniline (PANI) as corrosion inhibitors for metals.

In this study, the effect of the addition of praseodymium (Pr³⁺) cations on the corrosion inhibition performance of PANI for AZ31 magnesium alloy was appraised through electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests.

The results of EIS and potentiodynamic polarization tests indicated the improvement of corrosion resistance of AZ31 during different immersion times.

This anti-corrosion ability of PANI/Pr³⁺ composite applies as non-toxic environmentally friendly corrosion inhibitor on the self-healing corrosion protection properties.

The conductive polymers are interested for many industries. The reported data can be used by the formulators working in the R&D departments.

The anti-corrosion ability of PANI/Pr³⁺ composite present a novel and high effective route against metal corrosion besides application of toxic corrosion.

The application of titanium dioxide coating in the field of architectural heritage is a great challenge. Therefore, the main objective of this study is to study the synthesis, characterization and corrosion inhibition performance of Pr³⁺ cations doped PANI nano-fibers as an anti-corrosion additive for AZ31 magnesium alloy in 3.5 Wt.% NaCl solution.

The purpose of this paper is to investigate the effect of different PHS on the surface chemistry of fumed silica treated with aminopropyltrimethoxysilane (APTMS).

The reaction conditions involved variation of pH ranging from acidic to alkaline. Different analytical techniques including FT‐IR spectroscopy, thermogravimetric analysis (TGA), CHN and Zeta potential analyses were employed to investigate the surface chemistry of treated particles. In addition, the stability of silanised silica dispersions were studied using turbidimetric and rheometric measurements.

It was revealed that in all conditions silica was more or less chemically grafted by the silane. When the pH of treating bath was adjusted to 1‐2 prior and during the reaction, 58 percent grafting was observed, as obtained by CHN and TGA analyses. At very alkaline conditions, however, the grafting content declined to 29 percent. The variations in grafting were dependent on the silane hydrolysis and its further condensation with the silica surface. Zeta potential measurements showed a drastic change from −7.1 mv to +18.01 mv (at pH 7) for the untreated particle and the one with the highest grafting, respectively. The dispersion stability of differently treated particles varied in solvents with different Hansen solubility parameters (HSP). Moreover, due to the variations of surface chemistry of particles, their rheological behaviours were significantly influenced.

The results obtained in this work showed that the surface chemistry of fume silica could be tuned with treating method. The highest content of grafting led to a better dispersion in solvents having greater hydrogen bonding component and to an inferior dispersion in solvents with higher polar component.

Reducing wear of undercarriage track propulsion systems used in heavy construction equipment decreases the maintenance costs and increases the equipment's life. Therefore, understanding key factors that affect the wear rate is critical. This study is an attempt to predict undercarriage wear.

This research analyzes a sample of track-type dozers in the eastern half of North Carolina (NC), USA. Sand percentage in the soil, precipitation level, temperature, machine model, machine weight, elevation above sea level and work type code are considered as factors influencing the wear rate. Data are comprised of 353 machines. Machine model and work code data are categorical. Sand percentage, elevation, machine weight, average temperature and average precipitation are continuous. ANOVA is used to test the hypothesis.

The study found that only sand percentage has a significant impact on the wear rate. Consequently, a regression model is developed.

The regression model can be used to predict undercarriage wear and bushing life in soils with different sand percentages. This is demonstrated using a hypothetical scenario for a construction company.

This work is useful in managing maintenance intervals of undercarriage tracks and in bidding construction jobs while predicting machine operating expense for each specific job site soil makeup.

During hospitalization, children are faced with physical disorders and many psychological challenges. One important factor affecting children is the environmental design of the hospital. The inappropriate design of hospitals may contribute to an increase in fear, anxiety and behavioral disorders. The purpose of this study is to use children’s perspectives to evaluate the importance and impact of effective environmental factors to generate children’s hospital design guidelines.

In this study, children’s desired atmosphere during treatment was examined via 16 drawings and 24 interviews from children at a children’s hospital in Iran.

The encoding of information extracted environmental components such as window view, color, hobby, playing, decorations, family presence, structure of hospital, presence of nurse, furniture, water features, light and green space. The results indicate that children prefer a hospital environment that provides entertainment facilities while also offering design features such as the presence of light, colorful decorations, the existence of green spaces and conditions suitable for their families to be present.

Depending on the location and their living conditions, the children’s prioritization can be different in any society. In addition, the data of this research was descriptive; thus, the conclusions must be considered tentative.

A number of studies focus on the needs of populations in developed countries. This topic has not been investigated in a major way via professionals in non-western countries such as Iran. Thus, the context of this study and present findings can be deemed unique.

This study aims to measure the effect of customers’ technology readiness and the quality of electronic services on customer satisfaction.

The statistical sample included 410 respondents from 24 branches of a private bank. The sampling method was questionnaire. Because of the structural and organizational similarity of private banks and the elimination of nuisance variables, a bank with the most branches and customers has been selected. To test the model, equation modeling was performed to test the hypotheses. Data were collected through a self-developed structured questionnaire, which served as the measurement tool as well.

The results of the study showed that technology readiness has a significant and positive effect on customer satisfaction through the quality of self-service. Moreover, the intermediate role of perceived value in this regard was confirmed; however, the role of trust was not confirmed.

Previous studies have considered technology readiness as an effective factor in the quality of self-service and customer satisfaction. In this study, apart from quality of service in self-service banking and customer satisfaction, two variables of trust and perceived value have been investigated. An attempt has also been made to address some questions, including “what the effect of customer technology readiness on perceived value of self-services as well as customer satisfaction is?” and “how it is possible to improve self-service quality in modern banking based on customer expectations?” or “what effects variables such as trust and perceived value have on customer satisfaction?” Having a glance at the studies done before, it can be understood that so far, there has been no study done using a mixture of these variables, yet societies’ demands for self-service operations grow day by day. It is, therefore, mandatory to study the prerequisites associated with any actions before one is taken. The paper contributes in the following way: trust and perceived value are added to the the study because of their role in customer satisfaction. In addition, for the first time, variables have been studied, which had never been under focus in any studies in developing countries before.

The purpose of this study is to investigate the effect of catalyst distribution in the combustion catalytic layer on heat and mass transport characteristics of the auto-thermal methanol steam reforming microchannel reactor.

Computational fluid dynamics (CFD) method is used to study four different gradient designs. The corresponding distributions of temperature, species and chemical reaction rate are provided and compared.

The distributions of species, temperature and chemical reaction rate are significantly affected by the catalyst distribution in the combustion catalytic layer. A more uniform temperature distribution can be observed when the gradient design is used. Meanwhile, the methanol conversion rate is also improved.

This work reveals the effect of catalyst distribution in the combustion catalytic layer on heat and mass transport characteristics of the auto-thermal methanol steam reforming microchannel reactor and provides guidance for the design of reactors.

The temperature uniformity and hydrogen production performance can be improved by the gradient design in the combustion catalytic layer.