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Abstract This study presents wear and friction behaviour of AA2024/TiB2 composite developed in semi-solid temperature region of the alloy. The experiment is conducted based on full factorial design of experimental technique with three factors and three levels. Load, reinforcement amount, and sliding distance are the process parameters varied, and their influence is investigated using analysis of variance. Additionally, the correlation between the process parameters and the responses are determined using multiple linear regression equation. For wear rate, the load is the most influencing factor followed by sliding distance and reinforcement ratio. Similarly, for the coefficient of friction, the applied load is the most influencing factor, followed by the reinforcement ratio and sliding distance. The reinforcement ratio showed a negative effect on the wear and coefficient of friction. This shows that both decrease with an increase in the proportion of the particles in the base matrix. The wear mechanisms of the worn surfaces are also investigated using a scanning electron microscope, and it is noticed that the depth of grooves increased, and microcracks are noticed with an increase in the applied load. The developed composites can be used in application areas exposed to wear and friction.

The presence of lactic acid and galactose makes spray drying of acid whey (AW) a significant challenge for the dairy industry. In this study, a novel approach is explored to remove these compounds, utilizing food-grade microorganisms. For removing lactic acid, Corynebacterium glutamicum was selected, which has an inherent ability to metabolize lactic acid but does so slowly. To accelerate lactic acid metabolism, a mutant strain G6006 was isolated through adaptive laboratory evolution, which metabolized all lactic acid from AW two times faster than its parent strain. To eliminate galactose, a lactose-negative mutant of Lactococcus lactis that cannot produce lactate was generated. This strain was then co-cultured with G6006 to maximize the removal of both lactic acid and galactose. The microbially "filtered" AW could readily be spray dried into a stable lactose powder. This study highlights the potential of utilizing food-grade microorganisms to process AW, which currently constitutes a global challenge., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Christian Solem reports financial support was provided by Technical University of Denmark. Christian Solem reports a relationship with Technical University of Denmark that includes: employment., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)