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High energy consumption and poor processing quality are common problems in wood sawing. To address these issues, in this article, specific cutting energy and surface roughness were investigated with saw blade speed as control variables. Analysing the effect of parameters on specific cutting energy and surface roughness. The sawing parameters were optimised with the objectives of minimum specific cutting energy and minimum surface roughness. The findings indicate that specific cutting energy and surface roughness reduction with increasing rake angle; specific cutting energy and surface roughness decrease with increasing spindle speed; specific cutting energy decreases and surface roughness increases with increasing feed rate. ANOVA analysis reveals that sawing speed (n) has the most significant impact on specific cutting energy during oak cutting. The optimal solution derived from TOPSIS suggests a specific cutting energy of 2E7 J/m3 and a surface roughness of 1.758 μm. The innovation of this paper is the study of the specific cutting energy and the optimisation of parameters. These findings provide valuable theoretical and practical guidance for enhancing the efficiency and quality of oak processing while minimizing energy consumption. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to determine the friction coefficient μ and maximum drawing force in deep drawing process of aluminum alloy EN AW 1050 utilizing strip drawing method. Influence and interaction between lubrication condition, blank holder force and strip surface roughness on maximum drawing force and friction coefficient are investigated. Response surface methodology and D‐Optimal design are utilized in order to create an experimental plan. According to the design, 23 strip drawings experiments are performed and statistical analysis was done. The regression and variance analysis results with 18 significant mathematical models which are derived in order to describe influence of mentioned parameters on friction coefficient and maximum drawing force. Results are discussed according to previous research. Finally, the optimization of processing parameters is performed aiming for lower friction coefficient and maximal drawing force. [ABSTRACT FROM AUTHOR]

Aluminium metal matrix composites are comprehensively used in a variety of applications comprising marine, aerospace, automobiles etc. Being less dense and having low thermal coefficient of expansion, they have better wear resistance and corrosion rates. To develop strength and corrosion properties aluminium hybrid composites are employed, where tungsten carbide and graphite particles are the reinforcements. The composite was fabricated by stir casting due to its cost effectiveness and better availability among other fabrication methods. Immersion tests have been conducted to find the corrosion rate. Scanning electron microscopy and energy dispersive spectroscopy analysis were carried out before and after the corrosion tests which reveals pitting corrosion. Furthermore, input parameters such as concentration of electrolyte, time, contents of tungsten carbide particles and contents of graphite particles are considered by using response surface methodology and the mathematical models are constructed. [ABSTRACT FROM AUTHOR]

Abstract: Anaerobic digestion of biowaste allows a sustainable production of bioenergy and reduces environmental burden. The anaerobic digestion phase was modeled with Anaerobic Digestion Model No. 1 (ADM1), which was extended to include three genera of propionate‐oxidizing bacteria and two routes of propionate degradation, namely methyl‐malonyl CoA and C6‐dismutation pathway. Kinetic parameters for anaerobic propionate oxidation were determined with defined tricultures of the three propionate‐oxidizing genera together with hydrogenotrophic and acetotrophic methanogens and implemented into ADM1, resulting in the improved model ADM1xpro. [ABSTRACT FROM AUTHOR]

The enzymatic hydrolysis of methyl octanoate via immobilized Candida antarctica lipase B was studied as an exemplary reference system from the field of enzymatically catalyzed liquid-liquid-solid systems. The experimental investigation of this system was performed in an innovative recycle packed-bed reactor with continuous liquid-liquid phase separation. This setup allows for both a biphasic as well as a singular phase reactor feed. For the first time, a holistic experimental investigation of both operation modes at various operating conditions was conducted. In addition to the presentation of the experimental results, the basics of the mathematical modeling are shown and a model validation is performed. [ABSTRACT FROM AUTHOR]

The integration of electrolysis-H2 from renewable electricity (wind, solar) in the production of liquid hydrocarbon energy carriers may transfer the fluctuating nature of renewable energies to the chemical process. By means of a mathematical model step-change experiments in a lab-scale reactor were analyzed to gather information about catalyst behavior under transient conditions. First results suggest that reaction kinetics determined under steady-state conditions are sufficient to characterize transient operation. [ABSTRACT FROM AUTHOR]