Magnetron‐sputtering inert‐gas condensation is an emerging technique offering single‐step, chemical‐free synthesis of nanoparticles with well‐defined morphologies optimized for specific applications. In this study, the authors report a flexible approach to produce Fe nanocubes as building blocks for high‐performance NO2 gas sensor devices, and hybrid FeAu nanocubes with magneto‐plasmonic properties. Considering that nucleation happens within a short distance from the sputtering target, the authors utilize the high‐permeability and resultant screening effect induced by magnetic Fe targets of various thicknesses to manipulate the magnetic field configuration and plasma confinement. The authors thus readily switch from bimodal to single‐Gaussian size distributions of Fe nanocubes by modifying their primordial thermal environments, as explained by a combination of modeling methods. Simultaneously, the authors obtain a material yield increase of more than one order of magnitude compared to experiments using postgrowth mass filtration. The effectiveness of the method is demonstrated by the deposition of Fe nanocubes on microhotplate devices, leading to unprecedented NO2 detection performance for Fe‐based chemoresistive gas sensors. The exceedingly low detection limit down to 3 ppb is attributed to a morphological change in operando from Fe/Fe‐oxide core/shell to specific hollow‐nanocube structures, as revealed by in situ environmental transmission electron microscopy.

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Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept of surface tension through simple experiments.

Experimental measurement of lithium distribution across the depth of a thick porous graphite electrode using operando microXRD and numerical modelling provide an unprecedented view of the lithiation of graphite.

SummaryReactive oxidant species produced by phagocytes have been reported as being involved in the killing of Aspergillus fumigatus. Fungal superoxide dismutases (SODs) that detoxify superoxide anions could be putative virulence factors for this opportunistic pathogen. Four genes encoding putative Sods have been identified in the A. fumigatus genome: a cytoplasmic Cu/ZnSOD (AfSod1p), a mitochondrial MnSOD (AfSod2p), a cytoplasmic MnSOD (AfSod3p) and AfSod4 displaying a MnSOD C-terminal domain. During growth, AfSOD1 and AfSOD2 were highly expressed in conidia whereas AfSOD3 was only strongly expressed in mycelium. AfSOD4 was weakly expressed compared with other SODs. The deletion of AfSOD4 was lethal. Dsod1 and Dsod2 mutants showed a growth inhibition at high temperature and a hypersensitivity to menadione whereas the sod3 mutant had only a slight growth delay at high temperature. Multiple mutations had only an additive effect on the phenotype. The triple sod1/sod2/sod3 mutant was characterized by a delay in conidial germination, a reduced conidial survival during storage overtime, the highest sensitivity to menadione and an increased sensitivity to killing by alveolar macrophage of immunocompetent mice. In spite of these phenotypes, no significant virulence difference was observed between the triple mutant and parental strain in experimental murine aspergillosis models in immunocompromised animals.

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The characterization of a scintillating metal organic framework (MOF) is not straightforward, mainly due to the small size and low density of the material. In this context, we present herein a generic method to give an easy access to the determination of a key parameter in the scintillation field, namely the light output. To reach this, MOF‐205 was first synthesized as millimetric‐size single crystals then sintered under pressure and temperature conditions to afford a pellet. The density was increased by 300% while maintaining optical properties on par with scintillation application. The as‐prepared scintillator was then characterized in terms of photoluminescence (PL; UV‐excited emission spectrum, time‐correlated single photon counting) and radioluminescence (RL) spectroscopy (beta‐excited emission spectrum, alpha, beta and gamma pulse height spectra, alpha/beta and alpha/gamma discrimination). Results were compared with commercial BC‐404 plastic scintillator performances as well as supported by MCNP6.2 simulation.

The effects of bias current on sensitivity and selectivity of resistive Metal-Oxide (MOX) sensors toward gases have been investigated. While the working temperature is kept constant, it has been found that tuning the polarization of the MOX thin film induces changes on its sensitivity toward gases. Besides, the behavior of sensitivity versus bias current depends on the nature of the gas and of the thin sensing film, meaning it is possible to enhance the selectivity by adjusting the polarization of different sensitive layers. This underutilized parameter provides a new way of improving easily gas sensors sensitivity and above all selectivity. It would then be interesting to polarize individually each sensor of a multi-sensor device in order to optimize the whole system performances, which may represent a breakthrough in the development of smart E-Nose. I.