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A good solder flux must simultaneously perform a number of important functions. It must promote thermal transfer to the area of the solder joint, enhance wetting of the solder on the base metal, and prevent oxidation of the metal surfaces at soldering temperatures. However, its primary task is to remove the tarnish layer from the metal joint that is about to be soldered. Despite the fact that the process of soldering electronic devices is a part of a multi‐billion dollar industry, the actual chemical reactions that occur during this cleaning process are not well documented. In the case of organic acid or water‐soluble fluxes, the flux reactions can be modelled by considering the interactions at the metal/metal oxide/electrolyte solution interface. Although such modelling systems have not frequently been applied to the behaviour of solder and fluxes, they are common for a number of other closely related chemical systems which are of practical interest, e.g., passivation layers on metals, electrochemical cells and metal oxide semiconductors. There are two types of reactions that can occur at the oxide/solution interface: acid‐base reactions and oxidation‐reduction reactions. The factors which affect the reaction rates and mechanisms are such variables as the structure of the metal oxide, temperature, pH, concentration of the electrolyte, and the chemical nature of the solute and solvent. By combining information about flux behaviour with available models of surface reactions, it should be possible to develop the theory of the flux reactions and to gain a better understanding of the factors which control the process.

High density PCB production requires ever closer investigation of the factors which influence the ability to fabricate efficient circuitry. One of these, etching, is examined, revealing that even that process alone is subject to the effect of physical, chemical and hydraulic parameters. Physical factors include raw materials, circuit geometry and process equipment, etcher spray systems being discussed at length. The implications of the chemical parameters are specifically linked with etchant formulation. Oxidation reduction potential and etchant density effects are also dealt with before the final section on hydraulic factors, where the importance of the design of the hydraulics system is underlined.

This paper presents a method for the determination of the kinetic parameters for the oxidation‐reduction hardening reactions of unsaturated polyesters with styrene. The method was based on the measurement of the change in the specific internal electric resistance during the hardening. This paper discusses the accelerating effects of ferrocene and some of its derivatives (acetylferrocene, benzoylferrocene, 1,1′‐diethylferrocene) on the hardening of unsaturated polyesters.

The behaviour of iron electrodes immersed in pH 8.9‐11.0 Na₂HPO₄ solutions was studied by potentiodynamic measurements (cyclic voltammetry) and scanning electron microscopy (SEM). The influence of proton and phosphate content, scan rate, anodic switching potential and other devised potential/time perturbation regimes were evaluated in order to obtain an understanding of the reactions involved during the passivation process. The oxidation‐reduction peaks were analysed using a thermodynamic approach. It was possible to reveal the most important reactions coming about on the electrode surface, which comprise, initially, the formation of Fe₃(PO₄)₂ and Fe(OH)₂ at ca. −0.8 V/SCE. Subsequently, these ferrous species are further oxidized to γ‐FeOOH at ca. −0.36 V/SCE, the latter being transformed into Fe₂O₃ in the passive region. Depending on the pH value (11.0) and scan rate (slow), Fe₃O₄ is clearly present as an intermediate oxide structure between the ferrous and ferric species mentioned earlier. In addition, scan rate was discovered to play a remarkable influence on the surface morphology observed during the SEM examinations.

As a natural fiber, yakwool has attracted much attention in textile processing due to its excellent properties and wearabilities. However, the main colors of yakwool are black and brown. Therefore, for extending the application scopes of the fiber, the decolorization of the yakwool fiber is usually needed, especially for the black fiber. The paper aims to discuss this issue.

In the paper, the properties of the yakwool fiber were tested first, especially the melanin granules in the fiber. Then, the decolorization of the yakwool fiber was studied using the oxidation–reduction decolorization method, and corresponding optimal process of the decolorization was given. Then, the properties of the decolorized yakwool fiber were tested and compared with those of the original fiber.

It is shown that, after decolorization, the physical and mechanical properties of the fiber were deteriorated, especially in terms of the strength and elongation. Therefore, the fiber became shorter and thinner, and the scales were damaged. When compared with the yarn spun from the original yakwool fiber, it was observed that the properties of the yarn spun from the decolorized yakwool fiber deteriorated because of the deterioration in the properties of the original fiber.

In the paper, for extending the application scopes of the yakwool fiber, the decolorization of the yakwool fiber was studied.

This study aims to report the development and experimental evaluation of two kinds of PANI@semiconductor based photocathodic anti-corrosion coating, for application on stainless steel substrates.

PANI was in situ chemical polymerized on TiO₂ and BiVO₄ particles, and FT-IR and SEM/EDS were used to understand the characteristics and elemental distribution of the composite particles. Composite coatings, which consisted of epoxy, PANI@TiO₂ or PANI@BiVO₄ and graphene, were prepared on the 304L stainless steel. Photoelectrochemical response measurement, electrochemical tests and immersion tests were used to assess the anti-corrosion performance of the prepared coatings in 45°C 3.5 wt.% NaCl solution. And the corrosion protection mechanism was further explained by combining with surface observation.

The photoelectrochemical response tests revealed the good photocathodic effect of the coatings, and the reversible oxidation-reduction properties of PANI (pseudocapacitive effect) leading to the repeated usage of the coatings. Consequently, the anti-corrosion mechanism of the composite coating is attributed to the physical barrier effect of the coating, the anodic protection effect of PANI and the photocathodic and energy store effect.

These kind coatings could prevent corrosion from day to night for stainless steel, which has great engineering application prospects on stainless steel corrosion protection.

There is strong agreement among educators at universities and colleges worldwide about the importance of assessing and measuring student learning. Yet, putting those best intentions into practice can be daunting within existing institutions. At Minerva, we had the luxury of starting a new college from scratch. We designed the institution to deliver specific student outcomes, and built all the operating practices and systems needed to support faculty and students in this pursuit. In this chapter, we share how Minerva defined what we teach, how we teach, and how our practices enable us to measure whether our students are indeed achieving the outcomes we had intended for them. We hope you might be inspired by learning about our approach, as we do believe that much of what we have put into place can be incorporated by other institutions to help their students achieve their learning outcomes.

This paper describes a study on the corrosion behaviour of archaeological bronze in simulated groundwater by means of a simulated occluded cell. The study revealed migration, enrichment and deposition patterns of ions in the environment and the cations produced by anodic dissolution during localised corrosion of bronze. The cycle voltametry technique was utilised for the first time on the study of electrochemical behaviour of the bronze/simulated occluded solution interface. The potential and current peaks of oxidation‐reduction at the cathode and anode in the occluded solutions at various time intervals facilitated a study of the corrosion products formation processes and their formation speeds.

This study examines and estimates the relationship among identified factors or determinants for the adoption of water ionizers by customers.

To this end, the questionnaire is prepared to have the preferences of customers based on the factors or enablers identified for the analysis of customers' perceptions toward the adoption of water ionizers. Recipients are identified to collect their preferences for the factors responsible for the adoption. The convenience sampling method is used in administering the questionnaire for the study. The structural equation modeling (SEM) technique is used to construct the model for defining the relationship between measured and latent variables using the lavaan, haven, psych and semPlot libraries in R software.

The study reveals that product features, which include pH value, oxidation-reduction potential (ORP) and micro-clustering (MC), are influenced by environmental sustainability (ES), and as a result, product features and product outcomes (brand value (BV), customer recommendation (CR) and perceived usefulness (PU)) together influence the adoption of water ionizers by customers.

Water ionizers have appeared as consumer electronic appliances designed to alter the pH and ORP of water through an electrolysis process. There are proven benefits to improved water quality across different pHs for its health benefits (HB) and other commercial and household uses. The study recommends that potential HB perceived through water ionizers and product features, which are supported by ES, and helps customers decide on the adoption of water ionizers.

The study supports comprehending the relationships between consumer behavior, sustainable practices and innovative technologies like water ionizers as society places a greater emphasis on environmentally conscious living and sustainable living. This study aims to clarify the elements affecting the adoption and perception of water ionizers from a sustainability perspective through an extensive assessment of the literature and empirical analysis.

The literature on electroless gold deposition processes is reviewed both with respect to bath formulation and the kinetics of the electrochemical reduction and oxidation reactions involved. Some modified formulations are discussed in more detail and components processed by the use of electroless gold deposition are illustrated.