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Triboelectric nanogenerators (TENGs) are emerging as new technologies to harvest electrical power from mechanical energy. With the distinctive working mechanism of triboelectric nanogenerators, they attract particular interest in healthcare monitoring, wearable electronics, and deformable energy harvesting, which raises the requirement for highly conformable devices with substantial energy outputs. Here, a simple, low‐cost strategy for fabricating stretchable triboelectric nanogenerators with ultra‐high electrical output is developed. The TENG is prepared using PTFE micron particles (PP‐TENG), contributing a different electrostatic induction process compared to TENG based on dielectric films, which was associated with the dynamics of particle motions in PP‐TENG. The generator achieved an impressive voltage output of 1000 V with a current of 25 μA over a contact area of 40 × 20 mm2. Additionally, the TENG exhibits excellent durability with a stretching strain of 500%, and the electrical output performance does not show any significant degradation even after 3000 cycles at a strain of 400%. The unique design of the device provides high conformability and can be used as a self‐powered sensor for human motion detection. [ABSTRACT FROM AUTHOR]

This study simulated the effects of direct predatory pressure, indirect predatory pressure, and conspecific injury signals on sea cucumber (Apostichopus japonicus) to determine changes in the activity of immune defense enzymes (lysozyme, acid phosphatase, alkaline phosphatase) and antioxidant stress enzymes (catalase, superoxide dismutase, malondialdehyde). Samples of sea cucumber juveniles were collected at 3 h, 12 h, 72 h, and 96 h post predatory stress, and six enzymes related to immune defense and antioxidant stress were selected for activity assays, namely, lysozyme (LZM), acid phosphatase (ACP), alkaline phosphatase (AKP), superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA). The results indicate that under direct predatory pressure, the activity of catalase in sea cucumbers was significantly higher than that of the control group at 3 h (P < 0.05), while the activities of acid phosphatase, alkaline phosphatase, and catalase were significantly lower at 72 h (P < 0.05). Under indirect predatory pressure, the activity of malondialdehyde in sea cucumbers was significantly higher than that of the control group at 12 h (P < 0.05), the activity of alkaline phosphatase was significantly higher at 72 and 96 h (P < 0.05), the activity of catalase was significantly lower at 72 h, and the activity of superoxide dismutase was significantly higher at 72 h (P < 0.05). Under the influence of conspecific injury signals, the activity of malondialdehyde in sea cucumbers was significantly higher than that of the control group at 12 h (P < 0.05), and the activity of superoxide dismutase was significantly higher at 96 h (P < 0.05). The sea cucumber enhanced its antioxidant capacity 3 h after facing a predator, while its immune defense mechanism was suppressed at 72 h. When facing indirect predatory pressure, the sea cucumber may have made immune and antioxidant preparations for the arrival of unknown risks. The experimental results show that predatory pressure has a significant impact on the immune and antioxidant functions of sea cucumbers, which may be related to the physiological state and environmental adaptability of the sea cucumber. This study provides a new perspective for understanding how sea cucumbers cope with predatory pressure in the natural environment and offers theoretical support for the cultivation management of sea cucumbers. [ABSTRACT FROM AUTHOR]

Late Carboniferous–Early Permian granitoids are widespread in the Tianshan area and their tectonic setting is controversially discussed. Our research presents fresh whole-rock geochemical and Pb isotopic data, along with zircon U-Pb ages and Hf isotopic data for representative monzonitic and granitic intrusions in the Kumishi area. The aim is to decipher their magma sources and illuminate their geodynamic evolution. Zircon U-Pb dating results reveal that biotite monzonites in the Central Tianshan Belt were emplaced at 312.7 ± 2.9 Ma, while the quartz-monzonites and syenogranites in the South Tianshan Belt were formed at 284.5 ± 2.4 Ma and 283.4 ± 3.9 Ma, respectively. The biotite monzonites generally exhibit metaluminous and high-K calc-alkaline characteristics. They have a positive εHf(t) value (+4.9–+14.1), and are enriched in LREEs and LILEs but depleted in HREEs and HFSEs. These characteristics indicate that they were derived from a mixed magma source of the lower crust and the input of components derived from the mantle wedge above the subduction zone. The quartz-monzonites and syenogranites are high-K calc-alkaline to shoshonitic I-type granites, with εHf(t) values of +14.9–+15.5 and +6.6–+14.9, respectively. They are enriched in LREEs but depleted in HFSEs (e.g., Nb, Ta, and Ti), displaying relatively flat HREE patterns and negative Eu anomalies. The genesis of these rocks is attributed to a partial melting of the lower crust in which mantle-derived magmas participated, which was triggered by an upwelling asthenosphere in a post-collisional extensional geodynamic setting. These granitoids, together with regional analysis of other magmatism in the study area, suggest that the Kumishi area has experienced an evolution from subduction to post-collision from the Late Carboniferous to the Early Permian, which constrains the local closure of the Paleo-Asian Ocean. [ABSTRACT FROM AUTHOR]

The Qinling Orogenic Belt was formed by multi-stage convergence and subsequent collision between the North China Block and South China Block during the Palaeozoic to Late Triassic. Following the collision between the South Qinling Belt and the South China Block in the Late Triassic, the whole Qinling Orogenic Belt evolved into an intracontinental orogeny. However, the exact termination time of the Late Mesozoic intracontinental contractional deformation and the tectonic transformation from compression to extension remains unclear. The extensional shear zone developed in the West Qinling Orogenic Belt provides a crucial clue to revealing the tectonic transformation and uplift and exhumation of the orogenic belt. This study focuses on kinematics, deformation temperature, and geochronology of the shear zone in the West Qinling Orogenic Belt through detailed field structural analysis and laboratory analysis. The Taibai shear zone (TBSZ), located in the West Qinling Orogenic Belt, cuts across the Qinling Orogenic Belt along the NE–NEE direction and separates the Taibai pluton in the east from the Baoji pluton in the west. The NE–NEE-striking TBSZ is an extensional shear zone showing a top-to-the-NW sinistral shear sense. The TBSZ was formed under the high greenschist–low amphibolite facies conditions (300–550°C) in the middle-upper crust level (8–15 km). Zircon U–Pb dating and biotite and muscovite 40Ar/39Ar dating indicate that the TBSZ occurred at 120–113 Ma. The extensional TBSZ and normal faults on its hanging wall indicate the tectonic transformation and the extensional collapse of the Mesozoic intracontinental orogenic belt during the late Early Cretaceous. The Cretaceous extensional collapse of the Qinling Orogenic Belt also led to the rapid uplift and exhumation of the Taibai pluton and the North Qinling Belt in the east. [ABSTRACT FROM AUTHOR]

With the rapid increase of electrical energy consumption in metropolises, more and more power cables are utilized in power grid or urban power network to transmit and distribute electrical energy. Silicone rubber is widely used as polymeric insulating materials of power cable accessories due to their excellent electrical and thermal performances. However, under high dc electric field space charges can accumulate inside the silicone rubber, which will distort the electric field in the bulk of the material, influencing the reliability and safety of operation. A bipolar charge injection and transport model is adopted to investigate the accumulation of space charges and distortion of electric field in silicone rubber. It is found that when charge injection rate is higher than the charge migration rate, space charges will accumulate in the material and the accumulation increases with an increase in electric field. The influence of the Poole-Frenkel effect is then studied. It is found that stronger Poole-Frenkel effect can enhance the nonlinearity of effective carrier mobility of silicone rubber, reducing the accumulation of space charges. This indicates that tuning the nonlinearity of effective carrier mobility by nano-doping can suppress space charges, improving the reliability of power cable accessories.