Application of degradable organic electronics based on biomaterials, such as polylactic‐co‐glycolic acid and polylactide (PLA), is severely limited by their low thermal stability. Here, a highly thermally stable organic transistor is demonstrated by applying a three‐arm stereocomplex PLA (tascPLA) as dielectric and substrate materials. The resulting flexible transistors are stable up to 200 °C, while devices based on traditional PLA are damaged at 100 °C. Furthermore, charge‐ trapping effect induced by polar groups of the dielectric is also utilized to significantly enhance the temperature sensitivity of the electronic devices. Skin‐like temperature sensor array is successfully demonstrated based on such transistors, which also exhibited good biocompatibility in cytotoxicity measurement. By presenting combined advantages of transparency, flexibility, thermal stability, temperature sensitivity, degradability, and biocompatibility, these organic transistors thus possess a broad applicability such as environment friendly electronics, implantable medical devices, and artificial skin.

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Rational construction of a profitable microstructure in carbon-based electromagnetic composites is becoming a promising strategy to reinforce their microwave absorption performance. Herein, the microstructure design is innovatively coupled with a metal–organic frameworks (MOFs)-derived method to produce hollow Co/C microspheres (Co/C-HS). The resultant composites combine the advantages of hollow microstructures and good chemical homogeneity. It is found that the pyrolysis temperature plays an important role in determining the electromagnetic properties of these hollow Co/C microspheres, where high pyrolysis temperature will increase relative complex permittivity and decrease relative complex permeability. When the pyrolysis temperature is 600 °C, the sample (Co/C-HS-600) will show improved impedance matching and good attenuation ability, and thus an excellent microwave absorption performance with strong reflection loss (−66.5 dB at 17.6 GHz) and wide response bandwidth (over −10 dB, 3.7–18.0 GHz) can be achieved. By comparing with Co/C composites derived from conventional ZIF-67, it can be validated that a hollow microstructure is greatly helpful to upgrade the performance by boosting dielectric loss ability and suppressing a negative interaction between the carbon matrix and incident electromagnetic waves, as well as providing multiple reflection behaviors. We believe that this study may open a new avenue to promote the electromagnetic applications of MOFs-derived carbon-based composites.

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A submicrometer-grained (SMG) Al−3% Mg solid solution alloy, with an initial grain size of ∼0.2 μm, was produced by intense plastic straining. Experiments show that tensile specimens of the SMG alloy exhibit high elongations to failure at low testing strain rates at the relatively low temperature of 403 K. The stress exponent is high (∼7–8) and calculations show deformation is within the region of power-law breakdown. The initial microstructure of the alloy consists of diffuse boundaries between highly deformed grains. At strain rates of ∼10−4 s−1 and lower, plastic deformation leads to dynamic recrystallization and the formation of highly nonequilibrium grain boundaries that gradually evolve into a more equilibrated configuration.

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The anodizing behavior of a lithium-containing aluminum alloy ͑AA 2099-T8͒ in an environmentally friendly electrolyte, namely tartaric-sulfuric acid ͑TSA͒, has been examined under potentiodynamic and potentiostatic conditions. Specifically, the dependence of the anodic film morphology and composition on the anodizing voltage was investigated. It is revealed that porous anodic films with well-defined cells were formed at relatively low voltages while porous anodic films with pores of increased dimensions and lateral porosity were formed at increased voltages. In addition, it is indicated that copper in the alloy matrix can be occluded in the anodic film material as copper-rich nanoparticles or it can be oxidized and incorporated into the film material as copper ions, depending on the anodizing voltage. In the latter case, the process is accompanied by oxygen gas generation within the film material, resulting in the lateral porosity in the anodic film. Further, the structures of the copper-rich nanoparticles have been determined and the mechanism of the formation of such nanoparticles has been discussed.