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Fractional calculus is an essential tool in studying new phenomena in hydromechanics and heat and mass transfer, particularly anomalous hydromechanical advection–dispersion considering the fractal nature of the porous medium. They are valuable in solving the urgent problem of convective mass transfer in a porous medium (e.g., membranes, filters, nozzles, convective coolers, vibrational prillers, and so on). Its solution allows for improving chemical engineering and technology workflows, refining process models for obtaining porous granular materials, realizing the convective cooling of granular and grain materials, and ensuring the corresponding apparatuses’ environmental safety. The article aims to develop a reliable convective mass transfer model for a porous medium and proposes a practical approach for its parameter identification. As a result, a general scientific and methodological approach to parameter identification of the fractional convective mass transfer model in a porous medium was proposed based on available experimental data. It mainly used Riemann–Liouville fractional time and coordinate derivatives. The comprehensive application of the Laplace obtained the corresponding general solution transform with respect to time and a coordinate, the Mittag-Leffler function, and specialized functions. Different partial solutions in various application case studies proved this solution. Moreover, the algorithm for practically implementing the developed approach was proposed to evaluate parameters for the considered model by evaluation data. It was reduced to the two-parameter model and justified by the available experimental data.

High-energy milling process on ceramic material was analyzed, it process generate modifications on morphology and particle size, the process showed the last one relation with the crystallite size, about of structural analysis Rietveld refinement let identify anisotropy with the variations on crystalline planes and deformations occasioned by milling process, the particle size decrease with the process, similar tendency was observed on the images obtained by Scanning Electronic Microscopy, an result in this study was the variation on magnetization without chemical reaction under non-stoichiometric conditions and the agglomerates sizes observed on samples it is by process.

Industry is continuously searching for solutions to increase flexibility and quality in parallel with cost reductions. This paper presents a case study of using set-based design method to develop a gripping system for an innovative three-dimensional bending and forming technology of extruded aluminium profiles. Traditionally, profiles are formed by mandrel-based stretch-bending to improve cross-sectional stability and spring-back, sometimes combined with subsequent calibration e.g. by hydroforming. However, in the highly competitive automotive industry, where light-weighting is high on the agenda, design and process flexibility, tooling cost and dimensional accuracy are important factors to increase value at a reasonable cost. In this paper, a set-based concurrent engineering approach is used to identify, evaluate and prioritize gripping methods to enable three-dimensional bending meeting automotive requirements for dimensional accuracy. The results demonstrate a multitude of options, providing trade-offs between flexibility and function. Further work will be to build a physical demonstrator to validate output from the set-based method used to systematically narrow down the solution space. [ABSTRACT FROM AUTHOR]

Fractional calculus is an essential tool in studying new phenomena in hydromechanics and heat and mass transfer, particularly anomalous hydromechanical advection-dispersion considering the fractal nature of the porous medium. They are valuable in solving the urgent problem of convective mass transfer in a porous medium (e.g., membranes, filters, nozzles, convective coolers, vibrational prillers, and so on). Its solution allows for improving chemical engineering and technology workflows, refining process models for obtaining porous granular materials, realizing the convective cooling of granular and grain materials, and ensuring the corresponding apparatuses' environmental safety. The article aims to develop a reliable convective mass transfer model for a porous medium and proposes a practical approach for its parameter identification. As a result, a general scientific and methodological approach to parameter identification of the fractional convective mass transfer model in a porous medium was proposed based on available experimental data. It mainly used Riemann-Liouville fractional time and coordinate derivatives. The comprehensive application of the Laplace obtained the corresponding general solution transform with respect to time and a coordinate, the Mittag-Leffler function, and specialized functions. Different partial solutions in various application case studies proved this solution. Moreover, the algorithm for practically implementing the developed approach was proposed to evaluate parameters for the considered model by evaluation data. It was reduced to the two-parameter model and justified by the available experimental data.

Advanced manufacturing processes (AMP) are characterized by innovative variables of a technological and organizational nature which tend to change with workplaces, processes and conventional work practices, and can generate, as well as traditional occupational risks, other so-called new and emerging risks (NER). The main innovative aspect of this paper is that such risks have been analyzed applying recent specific models in the field, with the overall aim of identifying susceptible AMP of generating NER. From the results the main apparent conclusion is that there is NER of a general nature susceptible in AMP but it is not possible, in most cases, to establish direct links with specific AMP. However, it has been possible to identify among those NER a set of technological aspects with which can be established a starting point to facilitate the identification of AMP that are potential generators of NER. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mathematical model developed for an advanced integrated water treatment plant. [•] Highly integrated scheme is novel in ensuring by-product recovery and water reuse. [•] Model successfully predicted plant performance. [•] Study will facilitate industrial scale up of this new and advanced scheme. [Copyright &y& Elsevier]

Abstract: The objective of this study was to investigate the degradation and mineralization of an azo-dye, the Congo red, in aqueous solutions using ozone. Phytotoxicity and the inhibitory effects on the microbial activity of the raw and the ozonated solutions were also carried out with the aim of water reuse and environment protection. Decolorization of the aqueous solutions, disappearance of the parent compound, chemical oxygen demand (COD) and total organic carbon (TOC) removal were the main parameters monitored in this study. To control the mineralization of the Congo red, pH of the ozonated solution and heteroatoms released from the mother molecule such NH4 +, NO3 − and SO4 2− were determined. It was concluded that ozone by itself is strong enough to decolorize these aqueous solutions in the early stage of the oxidation process. Nonetheless, efficient mineralization had not been achieved. Significant drops in COD (54%) were registered. The extent of TOC removal was about 32%. Sulfur heteroatom was totally oxidized to SO4 2− ions while the central –N azo ring was partially converted to NH4 + and NO3 −. Results of the kinetic studies showed that ozonation of the selected molecule was a pseudo-first-order reaction with respect to dye concentration. The obtained results also demonstrate that ozone process reduced the phytotoxicity of the raw solution and enhanced the biodegradability of the treated azo-dyes-wastewater. Hence, this show that ozone remains one of the effective technologies for the discoloration and the detoxification of organic dyes in wastewater. [Copyright &y& Elsevier]