Due to its environmental friendliness and biodegradable ability, the enzymatic decolorization of azo dyes is the best option. However, the free enzyme suffers from various limitations, including poor stability, no repeatable use, and a high expense, which is the key drawback for its practical use. In this analysis, the laccase enzyme was immobilized in mesoporous silica coated magnetic multiwalled carbon nanotubes (Fe 3 O 4 -MWCNTs@SiO 2 ) by a glutaraldehyde cross-linker to create an easily separable and stable enzyme. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive Xray spectroscopy (EDX) were used to characterize the as-synthesized Fe 3 O 4 -MWCNTs@SiO 2 . Laccase immobilized in Fe 3 O 4 -MWCNTs@SiO 2 showed a good improvement in temperature, pH, and storage stability. Moreover, the operational stability of the biocatalyst was improved, retaining 87% of its original activity even after 10 cycles of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) oxidation. The biocatalysts were applied for the decolorization of selected azo dyes without a mediator, and up to 99% of Eriochrome Black T (EBT), 98% of Acid Red 88 (AR 88), and 66% of Reactive Black 5 (RB5) were decolorized. Based on these properties, the biocatalysts can be potentially utilized in various environmental and industrial applications.

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The #25 teller rosette (TR) random packing was used to enhance foam drainage in foam fractionation under continuous steady‐state conditions and tested using sodium dodecyl sulfate (SDS) as a model surfactant. A column without the #25 TR served as control. The results demonstrated that the #25 TR was capable of enhancing the foam drainage and enrichment ratio while reducing the liquid holdup. The experiment was set up with optimized feed flow rate, liquid pool height, air flow rate, and SDS feed concentration. The enrichment ratio obtained by the #25 TR column was 1.76 times higher compared with the control column. Based on the mass balances and equilibrium relationship, a new method for graphical illustration of theoretical stages is also presented.

The purpose of this article is to show that African theology is both a practical theology as well as a speculative theology. It is a theology which was born from the perspective of finding a proper method of evangelization on the African continent. To do this, this theology went through different stages which led it to its scientific maturity. Thanks to the efforts made, this theology has provided a way to a deeper evangelization in the african cultural context. Inculturation, as one of the ways of doing theology in Africa, has become a key word in African theology. Inculturation has the advantage of frank and uncompromising dialogue between the Gospel and cultures. This dialogue subsequently allows an appropriation of the Gospel message in various african cultural backgrounds.