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Despite extensive efforts on studying the decomposition mechanism of HMX under extreme condition, an intrinsic understanding of mechanical and chemical response processes, inducing the initial chemical reaction, is not yet achieved. In this work, the microscopic dynamic response and initial decomposition of β-HMX with (1 0 0) surface and molecular vacancy under shock condition, were explored by means of the self-consistent-charge density-functional tight-binding method (SCC-DFTB) in conjunction with multiscale shock technique (MSST). The evolutions of various bond lengths and charge transfers were analyzed to explore and understand the initial reaction mechanism of HMX. Our results discovered that the C-N bond close to major axes had less compression sensitivity and higher stretch activity. The charge was transferred mainly from the N-NO2 group along the minor axes and H atom to C atom during the early compression process. The first reaction of HMX primarily initiated with the fission of the molecular ring at the site of the C-N bond close to major axes. Further breaking of the molecular ring enhanced intermolecular interactions and promoted the cleavage of C-H and N-NO2 bonds. More significantly, the dynamic response behavior clearly depended on the angle between chemical bond and shock direction.

We study the intrinsic shock decomposition mechanism of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) via quantum-based multiscale molecular dynamics methods. Some distinctive and novel insights are obtained based on our simulation results. The reaction is always initiated by hydrogen transfer both in intra- and intermolecular conditions. The carbon atom is mostly oxidized by nitro O directly. The earliest gas product NO2 is produced with the cleavage of C-NO2. The initial N2 mainly derives from the interaction between NO and TATB molecular residues. More intriguingly, we detect 28 kinds of heterocyclic structures involved in the TATB decomposition process. Most of the newly formed C–N heterocycles possess high stability, which obviously inhibit the further reaction toward releasing C oxides and N2. These results reveal not only the early shock decomposition properties of TATB but also the different reaction mechanisms between sensitive and insensitive explosives.

Morphine tolerance is a clinical challenge in pain management. Emerging evidence suggests that microRNA (miRNA) plays a regulatory role in the development of morphine tolerance. miR-219-5p (miR-219) targets calmodulin-dependent protein kinase II γ (CaMKIIγ) to activate central pain sensitization via N-methyl-D-aspartate (NMDA) receptor. Therefore, we hypothesized that miR-219-5p attenuates morphine tolerance by targeting CaMKIIγ. We found that the expression of miR-219-5p was decreased significantly after chronic morphine treatment. Overexpression of miR-219-5p by lentivirus injection prevents the development of morphine tolerance. CaMKIIγ, the target gene of miR-219-5p was downregulated by overexpression of miR-219-5p both in vivo and in vitro. Furthermore, we found that lentiviral-mediated miR-219-5p decreased the expression of NMDA receptor subunit 1 (NR1), leading to attenuation of morphine tolerance. Overall, the data demonstrate that miR-219-5p plays a crucial role in alleviating morphine tolerance by inhibiting the CaMKII/NMDA receptor pathway. Overexpression of miR-219-5p may be a potential strategy to ameliorate morphine tolerance.

In this study, we have shown the protective effect of intrathecal PDTC on the development of nociceptive behaviors induced by CCI in rats. The activation of NF-κB pathway may contribute to spinal microglial activation and CX3CR1 up-regulation.

The lithium-ion capacitors (LICs) become potential energy storage devices because they have both outstanding energy density of lithium-ion batteries (LIBs) and excellent power density of supercapacitors (SCs). However, significant challenges such as the discrepant energy-storage mechanism of the anode and the cathode material must be addressed for their practical applications. We reported a method to enhance the electrochemical kinetics of CoP by combining with reduced graphene oxide(r-GO) conductive network and designed the 3D urchin-like CoP nanorods that reduce the volume expansion of CoP during Li + insertion/extraction. The resulting prepared high capacitive characteristic 3D CoP/r-GO nanocomposite electrode delivered a specific capacity of 510 mAh g −1 at 0.1A g −1 after 500 cycles in a LIB half-cell, and its b value is up to 0.93 by kinetic calculation. The LIC device assembled with the 3D CoP/r-GO nanocomposites anode and activated carbon (AC) cathode, it provided a distinctive energy density of 119.3Wh kg −1 (current density is 0.1A g −1 ) and power density of 8400 W kg −1 (current density is 4.8A g −1 ). This result indicates that the energy density and power density of LICs can be enhanced by improving the dynamic characteristics of the electrode material.

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The paramount focus in the construction of lithium-ion capacitors (LICs) is the development of anode materials with high reversible capacity and fast kinetics to overcome the mismatch of kinetics and capacity between the anode and cathode. Herein, a strategy is presented for the controllable synthesis of cobalt-based phosphides with various morphologies by adjusting the time of the phosphidation process, including 3D hierarchical needle-stacked diabolo-shaped CoP nanorods, 3D hierarchical stick-stacked diabolo-shaped Co 2 P nanorods, and 3D hierarchical heterostructure CoP@Co 2 P nanorods. 3D hierarchical nanostructures and a highly conductive project to accommodate volume changes are rational designs to achieve a robust construction, effective electron-ion transportation, and rapid kinetics characteristics, thus leading to excellent cycling stability and rate performance. Owing to these merits, the 3D hierarchical CoP, Co 2 P, and CoP@Co 2 P nanorods demonstrate prominent specific capacities of 573, 609, and 621 mA h g −1 at 0.1 A g −1 over 300 cycles, respectively. In addition, a highperformance CoP@Co 2 P//AC LIC is successfully constructed, which can achieve high energy densities of 166.2 and 36 W h kg −1 at power densities of 175 and 17524 W kg −1 (83.7% capacity retention after 12000 cycles). Therefore, the controllable synthesis of various simultaneously constructed crystalline phases and morphologies can be used to fabricate other advanced energy storage devices.