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Developmental sevoflurane exposure leads to widespread neuronal cell death known as sevoflurane-induced neurotoxicity (SIN). Receptor-interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like (MLKL)-driven necroptosis plays an important role in cell fate. Previous research has shown that inhibition of RIPK1 activity alone did not attenuate SIN. Since RIPK3/MLKL signaling could also be activated by Z-DNA/RNA binding protein 1 (ZBP1), the present study was designed to investigate whether ZBP1-mediated and RIPK3/MLKL-driven necroptosis is involved in SIN through in vitro and in vivo experiments. We found that sevoflurane priming triggers neuronal cell death and LDH release in a time-dependent manner. The expression levels of RIPK1, RIPK3, ZBP1 and membrane phosphorylated MLKL were also dramatically enhanced in SIN. Intriguingly, knockdown of RIPK3, but not RIPK1, abolished MLKL-mediated neuronal necroptosis in SIN. Additionally, inhibition of RIPK3-mediated necroptosis with GSK'872, rather than inhibition of apoptosis with zVAD, significantly ameliorated SIN. Further investigation showed that sevoflurane treatment causes mitochondrial DNA (mtDNA) release into the cytosol. Accordingly, ZBP1 senses cytosolic mtDNA and consequently activates RIPK3/MLKL signaling. This conclusion was reinforced by the evidence that knockdown of ZBP1 or depleting mtDNA with ethidium bromide remarkably improved SIN. Finally, the administration of the RIPK3 inhibitor GSK'872 relieved sevoflurane-induced spatial and emotional disorders without influence on locomotor activity. Altogether, these results illustrate that ZBP1 senses cytosolic mtDNA to induce RIPK3/MLKL-driven necroptosis in SIN. Elucidating the role of necroptosis in SIN will provide new insights into understanding the mechanism of anesthetic exposure in the developing brain.

An unstable solid electrolyte interphase (SEI) and chaotic lithium ion flux are key impediments to commercial high-energy-density lithium batteries because of the uncontrolled growth of rigid lithium dendrites, which would pierce through the conventional polypropylene (PP) separator, causing short circuit and safety issues. Herein, the homogenization of lithium ion flux and the generation of stable SEI layers on lithium anodes were achieved via coating a fluorine-functionalized Ti3C2 (F-Ti3C2) nanosheets on PP separator (F-Ti3C2@PP). F-Ti3C2 nanosheets provide abundant ions pathways to homogeneously manipulate lithium ion flux and increase the Young’s modulus and electrolyte wettability of the separators. In addition, F species derived from the F-Ti3C2 nanosheets would promote the formation of LiF-rich SEI film. The synergistic effect contribute to the uniform lithium deposition. Symmetric Li|Li, asymmetric Li|Cu and full Li|LiFePO4 cells incorporated with the modified separators exhibit improved electrochemical performance even under lean electrolyte conditions. This work provides a feasible strategy to improve the performance of lithium batteries through both fluoridized SEI formation and lithium ion flux manipulation.

Aprotic Li-O2 batteries with high theoretical energy density are regarded as promising next-generation energy storage devices. However, the accumulation of discharge products (Li2O2) duiring the discharge/charge processes would lead to high overpotential, low round-trip efficiency and poor cycling stability of the batteries. Soluble redox mediators (RMs) have been proved to be efficient in promoting the oxidation of Li2O2 particles. However, the self-discharge of the electrochemically oxidized RMs (RMsox) on the surface of Li metal would accelerate the formation of lithium dendrites. In this work, nitrogenous radicals, 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH), is designed and employed as a RMs to lower the overpotential of Li–O2 batteries. Moreover, the self-discharge of the oxidized DPPH on the surface of Li metal and the formation of lithium dendrites are successfully suppressed by the formation of graphene/luteolin protective layer on Li metal. Consequently, an ultrastable cycle stability (>150 cycles) is achieved with DPPH and the stable graphene/luteolin protective layer for the Li metal anodes. These synergistic effect of RMs and stable Li protective layer may inspire the development of sustainable and durable Li–O2 batteries.

Inferior charge transport in discharge products is one of the main factors restricting the technological potential of lithium-oxygen batteries. Here, we propose a strategy to enhance charge transport in discharge products by surface engineering of cathode catalysts with donor and acceptor sites to improve solid-solid interfacial electron transfer properties between catalysts and discharge products. Free-standing layered double oxides loaded with pyrolyzed sodium poly(aminobenzenesulfonate)-derived sulfur-doped carbon nanosheets and carbon nanosheets with sulfoxide groups are synthesized and utilized to investigate donor and acceptor sites effect on the performance of lithium-oxygen batteries. The free-standing cathode with hybrid donor and acceptor sites is capable of operation in oxygen with distinct (dis)charge plateau and superior cycling stability (over 60 cycles at a fixed capacity of 0.53 mAh cm−2). The superior properties are attributed to the enhanced charge transport in lithium peroxide by the formation of hole polarons/Li+ vacancies on acceptor sites and electron polarons/disordered lithium peroxide phase on donor sites. This work provides a promising route to enhance defective charge transport in discharge products by optimization of donor and acceptor sites on cathode catalysts for high-performance lithium-oxygen batteries.

Germanium-based materials are gaining increasing attention as promising anodes for Li-ion batteries (LIBs) due to their high specific capacity, good cycling stability and excellent rate performance. Similarly to Si, Ge-based anodes undergo a huge volume expansion and contraction during Li intercalation and deintercalation, causing a rapid and irreversible capacity decay. In this work, Ge nanoparticles are uniformly attached to a 3D ordered macroporous (3DOM) Ni framework (Ge/3DOM-Ni) via a facile drop-coating technique in order to address the volume expansion and stability issues plaguing Ge anodes. The 3D ordered macroporous Ni frameworks with high porosity act not only as highly conductive current collectors but also as a robust porous support for the formation of a thin layer of Ge nanoparticles. The three-dimensional porous network facilitates the penetration of the electrolyte and lithium ions. The possible alloy interface generated among the Ge nanoparticles and Ni framework during the calcination process ensures good electric contact among the nanoparticles and the 3D ordered macroporous Ni framework. When used as self-supporting binder-free anodes for lithium ion batteries, the Ge/3DOM-Ni electrode shows high rate performance and excellent structural and cycling stability. This work provides a facile and effective strategy for improving the electrochemical performance of Ge-based anodes.

Sodium ion batteries (SIBs) have great potential to be next-generation energy storage devices because of abundant sodium sources and its low cost. To improve the performance of SIBs, electrode materials with high capacities and cycling stabilities are highly desirable. Herein, inspired by the structure of a dandelion clock, core-shell TiO2@MoS2 composites were prepared by growing MoS2 nanoflakes on TiO2 nanospheres via a facial solvothermal method. The electrochemically stable TiO2 nanospheric core which likes the receptacle in a dandelion clock provides a robust support for the radial growth of MoS2 nanosheets, which like the pappi in the dandelion clock. The dandelion-clock-like structure can effectively prevent the aggregation of the MoS2 nanosheets, providing increased active sites. Strong interface interaction between TiO2 and MoS2 as revealed by XPS and HRTEM analyses could significantly promote the electron transfer and maintain the structural integrity of the composites. When used as anode materials for SIBs, the TiO2@MoS2 composites exhibit remarkable improved rate and cycling performance. This work indicates that the consideration of the morphology and structure is the key for the rational design and preparation of high performance electrode materials.

Lithium-sulfur batteries are considered as a promising candidate for next-generation energy-storage applications because of its high energy densities. However, the practical utilization of lithium–sulfur batteries is compromised by fast capacity decay, limited sulfur loading and significant polysulfide shuttling. Herein, we designed and prepared a free-standing lithium-sulfur electrode by loading sulfur into a hybrid material (Mo3Ni3N/Mo2C-CBC/S) constructed by growing Mo3Ni3N/Mo2C nanoparticles on carbonized bacterial cellulose film (CBC). High sulfur content up to 70 wt% and high areal sulfur loading of 15.5 mg cm−2 in Mo3Ni3N/Mo2C-CBC/S membrane are achieved. Reversible specific capacities of 1218 and 823 mA h g−1 are delivered for current rates of 0.1 and 1.0 C, respectively. A high capacity over 500 mA h g−1 is retained after 500 cycles at 1.0 C. The superior electrochemical performance of Mo3Ni3N/Mo2C-CBC/S composite is attributed to the unique structure feature and the synergistic effect of the Mo3Ni3N and Mo2C nanoparticles. The Mo3Ni3N/Mo2C component could suppress the dissolution and shuttling of the polysulfides and Mo2C could improve the electronic conductivity of the composite, consequently contributing to the excellent electrochemical performance of the composite.

Based on 3D numerical simulations, the restabilization of hydrogen–air rotating detonation engines (RDEs) from one stable state to another after the operating conditions are changed is investigated. After a sudden change is imposed on the injection stagnation pressure, the transition process is clarified and the transition time, needed by the RDE to stabilize at a new state, is calculated. It is found that the sudden change of the stagnation pressure has an immediate influence on the average axial velocity at the head end of the RDE, which increases abruptly and instantly with the sudden rise of the stagnation pressure. After that, the average axial velocity drops and the average pressure increases gradually at the head end until they reach a new stable state. The average pressure has a bounce and the average axial velocity fluctuates at the head end in the transition process of the sudden decrease of the stagnation pressure. The total transition time increases with the variation range of the stagnation pressure. However, the initial adjusting time is independent of the variation range of the stagnation pressure and it is about twice the cycle period of the detonation wave around the chamber, demonstrating the high stability of the RDE.

As is generally thought, continuously rotating detonation should keep going around the combustor regularly and has a fixed period. However, from the figures gotten by the data acquisition system, two kinds of breathing phenomena, Low Breathing and Deep Breathing, are discovered in the experiment. Actually they are caused by the changing mass flux, which stems from the pressure change in the combustor. The two kinds of breathing phenomena have different time scales and combustion mechanism. Reverse DDT is also discovered in one of the breathing phenomena. Since RDE is strong in thrust and high in efficiency, it has a great application foreground in the Aerospace Engineering.

A meshless approach, called the rigid-plastic reproducing kernel particle method (RKPM), is presented for three-dimensional (3D) bulk metal forming simulation. The approach is a combination of RKPM with the flow theory of 3D rigid-plastic mechanics. For the treatments of essential boundary conditions and incompressibility constraint, the boundary singular kernel method and the modified penalty method are utilized, respectively. The arc-tangential friction model is employed to treat the contact conditions. The compression of rectangular blocks, a typical 3D upsetting operation, is analyzed for different friction conditions and the numerical results are compared with those obtained using commercial rigid-plastic FEM (finite element method) software Deform3D. As results show, when handling 3D plastic deformations, the proposed approach eliminates the need of expensive meshing and remeshing procedures which are unavoidable in conventional FEM and can provide results that are in good agreement with finite element predictions.