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Plastic degradation by biological systems with re-utilization of the by-products could be a future solution to the global threat of plastic waste accumulation. Here, we report that the saliva of Galleria mellonella larvae (wax worms) is capable of oxidizing and depolymerizing polyethylene (PE), one of the most produced and sturdy polyolefin-derived plastics. This effect is achieved after a few hours' exposure at room temperature under physiological conditions (neutral pH). The wax worm saliva can overcome the bottleneck step in PE biodegradation, namely the initial oxidation step. Within the saliva, we identify two enzymes, belonging to the phenol oxidase family, that can reproduce the same effect. To the best of our knowledge, these enzymes are the first animal enzymes with this capability, opening the way to potential solutions for plastic waste management through bio-recycling/up-cycling. The crucial first step in the biodegradation of polyethylene plastic is oxidation of the polymer. This has traditionally required abiotic pre-treatment, but now Bertocchini and colleagues report two wax worm enzymes capable of catalyzing this oxidation and subsequent degradation at room temperature. [ABSTRACT FROM AUTHOR]

We studied the correlation of magnetic properties, structure, and giant magnetoimpedance (GMI) effect in Finemet-type FeCuNbSiB microwires. We observed that the GMI effect and magnetic softness of glass-coated microwires produced by the Taylor-Ulitovsky technique can be tailored by heat treatment. We observed a considerable magnetic softening of studied microwires after annealing. This magnetic softening correlates with the devitrification of amorphous samples. Amorphous Fe-rich microwires exhibited a low GMI effect (GMI ratio below 1%). Considerable enhancement of the GMI effect (GMI ratio up to 125%) has been observed in heat-treated microwires with a nanocrystalline structure. [ABSTRACT FROM AUTHOR]

We have studied Hitperm-type and Finemet-type glass-coated microwires with a nanocrystalline structure. In Hitperm-type microwires where the nanocrystalline structure has been obtained directly after melt quenching using the Taylor-Ulitovsky fabrication technique, we observed rectangular hysteresis loops and studied the domain wall propagation. We measured and analyzed the switching field dependence on the frequency in as-prepared and annealed Hitperm-type microwires. A conventional annealing results in a drastic change of the frequency dependence of the switching field. This effect might be interpreted considering the stress relaxation process. We have also studied the correlation of magnetic properties, structure, and giant magnetoimpedance (GMI) effect in Finemet-type FeCuNbSiB microwires prepared by the Taylor-Ulitovsky technique. We observed that both GMI effect and magnetic softness of Finemet-type glass-coated microwires can be tailored by heat treatment, and after annealing a considerable magnetic softening of studied samples has been achieved. This magnetic softening correlates well with the devitrification of amorphous samples. Amorphous Fe-rich microwires exhibit a low GMI effect (GMI ratio below 1%). A considerable enhancement of the GMI effect (GMI ratio up to 100%) has been observed in heat-treated microwires developing a nanocrystalline structure. [ABSTRACT FROM AUTHOR]

We studied giant magnetoimpedance (GMI) effect, magnetic, and magneto-optic properties of Finemet-type FeCuNbSiB microwires. We observed that GMI effect and magnetic softness of glass-coated microwires produced by the Taylor-Ulitovsky technique can be tailored either controlling magnetoelastic anisotropy of as-prepared FeCuNbSiB microwires or controlling their structure either by heat treatment or changing the fabrication conditions. We observed considerable magnetic softening of studied microwires after annealing. This magnetic softening correlates with the devitrification of amorphous samples. Amorphous Fe-rich microwires exhibited low GMI effect (GMI ratio below 1 %). Considerable enhancement of the GMI effect (GMI ratio up to 100 %) has been observed in heat-treated microwires with nanocrystalline structure. Some of as-prepared Fe-rich magnetic microwires exhibited nanocrystalline structure and GMI ratio up to 45 %. The magneto-optical study demonstrated the existence of helical surface magnetic structure in the as-prepared microwires. [ABSTRACT FROM AUTHOR]

We studied the giant magnetoimpedance (GMI) effect and magnetic properties of Finemet-type FeCuNbSiB microwires. We observed that the GMI effect and magnetic softness of glass-coated microwires produced by the Taylor-Ulitovski technique can be tailored by controlling the magnetoelastic anisotropy of as-prepared FeCuNbSiB microwires, and can also be considerably improved either by heat treatment and/or choosing the suitable fabrication conditions. We observed a considerable magnetic softening of the microwires after the appropriate annealing. This magnetic softening correlates with the devitrification of amorphous samples. Amorphous Fe-rich microwires exhibited a low GMI effect (GMI ratio below 5%). A considerable enhancement of the GMI effect (GMI ratio up to 100%) has been observed in heat-treated microwires with nanocrystalline structure. [ABSTRACT FROM AUTHOR]