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The intense requirement for bifunctional electromagnetic wave (EMW) absorbing materials is becoming the urgent focus and upgraded exploration for advanced application of absorbing EMW device in complex and extreme environments. Based on high dielectric loss capacity and superior chemistry inertness of graphite nanosheets, a two-dimensional (2D) graphite nanosheet decorated with graphite encapsulating soft-magnetic Ni3Fe nanocapsules was designed and exploited by introducing novel nitrogen catalyst in one-pot non-balance evaporating strategy. Through modulating the impedance matching and further optimal mass ratio, a minimum reflection loss (RL) of −35.8 dB at 7.35 GHz with an absorber thickness of 3.5 mm and a wide effective absorption bandwidth (EAB) of 5.5 GHz (RL ≤ −10 dB), which almost covered whole Ku-band, were realized with an absorber thickness of 2 mm. Combining the prominent EMW absorption, this 2D nanocomposite showed excellent comprehensive anti-corrosion ability to maintain the original microstructure in acidic, neutral and alkaline salty corrosion conditions. The successful exploration of 2D anticorrosive EMW absorber provides a significant insight for rational fabrication of futural bifunctional EMW absorbing devices in complex circumstances.

High-efficiency heat-dissipation materials are in urgent need in microelectronics industry in 5G era. However, large-scale, low-cost, and high-efficiency preparation technologies still have great challenges. Here, ultrahigh thermal and electric conductive graphite films prepared by graphite-phase carbon nitride (g-C3N4) catalyzed graphitization of polyimide film (PI) were reported for the first time. The graphite film obtained from 0.25 wt% g-C3N4 catalyzed polyimide graphitization (G0.25) has homogeneous and perfect graphene structure and state-of-the-art properties. The d-spacing of the graphite layers is about 0.335 nm, which is similar to the ideal layer thickness of graphene (0.334 nm). The thermal conductivity is 1781 W·m−1·K−1 and the conductivity is 1.63 × 106 S·m−1, which is 1.49 and 2.18 times of graphite film from pure PI film, 1.94 and 2.34 times of graphite film from commercialized Kapton film (I-film), respectively. The thermal conductivity of G0.25 film is 4.52 times of Cu and 7.46 times of Al. More importantly, the addition of g-C3N4 can reduce the graphitization temperature from 2800 to 2500 ℃, which can reduce the energy consumption by 20.5% in the whole polyimide graphitization process. The developed preparation technology has important guiding significance and very attractive industrial application value for the preparation of large-scale, low cost and high-quality heat dissipation materials.

Objective: This study explored the effect of circadian disorder on structure and function of neurons in hippocampus of mice. Methods: Forty male ICR mice were randomly divided into rhythm disorder group (RDG) and normal rhythm group (NRG). The RDG was treated with 3 h light/5 h dark and 5 h light/3 h dark light–dark (LD) cycle alternately. The normal rhythm group was treated with 12/12 h LD cycle. Electron microscope was used to detect the mouse hippocampal cell ultrastructure. Morris water maze was used to test mice cognitive function. The brain slice electric physiological techniques were used to detect synapses in the hippocampal Long-term potentiation (LTP) effect. Results: The time of through central area of RDG was less than that of NRG. The axoplasm in anterior-posterior membranes of synapses of RDG was dissolved and synaptic vesicles of RDG were decreased. Conclusion: Circadian rhythm disorder induced by irregular light–dark circle can lead to the structural damage of hippocampal neurons a...