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The Qinling Orogenic Belt (QOB) is a multi‐stage orogenic belt recording subduction and collision processes. The ductile shearing deformation with different properties and ages is developed on the boundary of the different litho‐tectonic units, which can be used to decipher the tectonic evolution of the QOB. Previous studies mainly concentrated on the pre‐Late Mesozoic shearing deformation, while the Late Mesozoic shearing deformation received less attention. It restricts the understanding of the Late Mesozoic tectonic evolution of the QOB. Hence, we conducted detailed field structural analysis and laboratory analysis of the Shagou shear zone (SGSZ) in the middle part of the Shangdan suture zone (SDSZ). The SGSZ, developed in the southern margin of the Baliping pluton, is an S–SSW‐dipping sinistral strike‐slip ductile shear zone with a top‐to‐the‐ESE shear sense. The mylonite protoliths are voluminous Late Triassic granites (200–215 Ma) and a small amount of Neoproterozoic granites (759 Ma) and Early Cretaceous granites (145 Ma). Microstructures and geothermobarometer results suggest that the ductile shearing deformation occurred under high greenschist–low amphibolite‐facies conditions (400–650°C) at middle crustal depths (13–21 km). Zircon U–Pb and amphibole‐biotite 40Ar/39Ar dating results constrain the timing of shearing deformation to 135–145 Ma and the rapid exhumation of the SGSZ to 115–135 Ma. Combining with the regional data, we consider that the sinistral strike‐slip shearing deformation in the SGSZ controls and accommodates the south‐eastward extrusion of the East SQB under the intracontinental compression. Subsequently, the intracontinental extension led to the rapid exhumation of the SGSZ. [ABSTRACT FROM AUTHOR]

Ultrathin, flexible and highly conductive materials that possess excellent electromagnetic interference (EMI) shielding performance are greatly needed, especially for the fabrication of stretchable shielding materials in practical applications such as wearable and foldable electronics. Graphene oxide (GO) sheets are modified with ethylenediamine to prepare cross-linked graphene films using a pressure-assisted self-assembly technique. FTIR and XPS results demonstrate that amine monomers are chemically bonded to GO sheets, with simultaneous reduction of GO sheets. After thermal annealing and followed with compression, the 6.6-μm-thick nitrogen-doping graphene film (rGO-EDA-2) is obtained with ultrahigh electrical conductivity of 8796 S cm−1. The excellent electrical conductivity is mainly attributed to nitrogen-doping effect, defects repair during chemical functionalization and removal of oxygenated groups. Ultrahigh electrical conductivity, multilayer structure and modified electronic structure with nitrogen doping lead to outstanding shielding performance for the rGO-EDA-2 film, with excellent shielding effectiveness (SE) of 58.5 dB and the specific SE/thickness of 43902 dB cm2 g−1, respectively. By fixing the rGO-EDA-2 film on the pre-stretched wavy substrate, the stretchable shielding composite is obtained, with constant EMI SE of 56.3 dB after repeated stretching. The pre-stretched wavy substrate allows the multilayer graphene film to achieve wavy structure after strain release, which is capable of bearing tensile strain up to 32.6%. This study could be significant in the applications of stretchable and wearable electronic devices. [ABSTRACT FROM AUTHOR]

To evaluate the performance and reliability of a new type of epoxy resin adhesive, the dynamic mechanical analysis (DMA) testing was performed at different levels of temperature and frequency after hydrothermal aging. The results of the DMA and the thermodynamic analysis that the performance of the adhesive has little change after hydrothermal aging for 30 days meant that the resistance to hydrothermal aging of this adhesive was excellent. In addition, the time-temperature equivalence principle and time-aging time equivalence principle were proposed here to offer additional insights into the dynamic mechanical performance of the newly developed adhesive. Moreover, an effective method by which the generalized curve of definite aging time in certain conditions of definite temperature and humidity can be obtained was introduced.Graphical abstract [ABSTRACT FROM AUTHOR]

Despite great recent progress, the processing of graphene oxide (GO) sheets in polymers are often one of the most challenging steps in fabricating graphene/polymer nanocomposites. The challenge is how to achieve high levels of dispersion and reduction of GO simultaneously, without any residual reducing agents in the composites. In this work, microwave irradiation is applied as a remote source to in situ reduce GO sheets embedded in the poly (vinyl alcohol) (PVA) matrix, which process maximizes the advantage of GO's solvent processability. The active response of GO to microwave irradiation allows for the uniform and selective heating of GO, leading to a minutes‐quick reduction of GO without physical damage to the polymer matrix. Significant improvements in the mechanical properties, electrical conductivities and glass transition temperatures (Tgs) of GO/PVA nanocomposites are achieved, and possible reasons for the improvements are also discussed. POLYM. COMPOS., 40:170–178, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]