MXene Lubricated Tribovoltaic Nanogenerator with High Current Output and Long Lifetime

Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.However,wear occurrence in friction interface will seriously reduce the performance of TVNGs as well as lifetime.Here,we employ MXene solution as lubricate to improve output current density and lifetime of TVNG simultaneously,where a high value of 754 mA m^(-2)accompanied with a record durability of 90,000 cycles were achieved.By comparing multiple liquid lubricates with different polarity,we show that conductive polar liquid with MXene as additive plays a crucial role in enhancing the electrical output performance and durability of TVNG.Moreover,the universality of MXene solution is well demonstrated in various TVNGs with Cu and P-type Si,and Cu and N-GaAs as material pairs.This work may guide and accelerates the practical application of TVNG in future.

Dynamic dielectric recovery performance of serial vacuum and SF6 gaps in HVDC interruption and its regulation method

Vacuum gaps have rapid dynamic dielectric recovery speed while SF6 gaps have high insulation strength. The series-connected vacuum and SF6 gaps are used as the main switch(MS), which combines their advantages. The work aims to verify the feasibility of serial vacuum and SF6 gaps in mechanical HVDC interruption. The test circuit of the dynamic dielectric recovery performance(DDRP) is set up. The DDRP is tested under free recovery condition by the high voltage pulse source. The DDRP of the vacuum circuit breaker(VCB) and SF6 gas circuit breaker(GCB) in DC interruption with active current injection is analyzed and compared. The test results indicate that the dielectric recovery duration of the VCB is below 30 μs while that of the GCB is above 100 μs. In order to achieve the cooperation between the VCB and GCB, a novel hybrid HVDC circuit breaker(CB) based on series-connected vacuum and SF6 gaps is proposed. The ‘voltage-zero’ duration is created by introducing the follow current loop and there more recovery time for the dielectric recovery of the MS. The voltage distribution is controlled by the voltage dividing method so that the VCB undertakes the initial transient recovery voltage(TRV) and the later TRV is took by the GCB. The theoretical synergy characteristic of the novel HVDC CB is obtained. The paper supplies a new method to improve the custom mechanical HVDC CB, which is useful to achieve the HVDC CB with less serial breaks.

Research review on the chemical constituents and pharmacological effects of Piper hancei

Traditional Chinese medicine“Shanju”,the dry stem of Piperaceae plant Piper hancei Maxim,is mainly distributed in southern China.Historically,P.hancei has been used as a substitute for the traditional Chinese medicine“Haitengtong”to treat rheumatism,joint pain,and asthma.At present,chemical constituents of it have been reported.In order to review the advances in chemical and pharmacologic studies and discuss the potential prospects for future investigation,the report summarized over 92 compounds isolated from P.hancei,including alkaloids,organic acid,sterol,aglycone,lignans,volatile oil and others.These compounds exhibited a wide range of bioactivities,such as anti-inflammation,inhibition of platelet aggregation,insecticidal effects and bactericidal activity.

A network-based pharmacology study on anti-hepatoma effect of the potential active constituents from Euphorbia fischeriana

Euphorbia fischeriana (Langdudaji in Chinese), a common traditional Chinese herbal medicine, has been used to treat cancer. It is well known that liver cancer is one of the most common malignant cancers worldwide. In this study, molecular docking and network analysis were carried out to explore the anticancer mechanism of active constituents from E. fischeriana as an effective therapeutic approach to treat liver cancer. Multiple active compounds of E. fischeriana were docked with 48 protein targets related with liver cancer. The networks of compound-target and target-pathway were constructed through network pharmacology analysis, predicting the relationships of active ingredients, significant targets and the key pathways. Our results demonstrated that Linoleic acid glyceride (FO7), Phytol (FO5), 3,4,6-tri-O-galloyl-D-glucose (FTa10), 3,7,11-tridecylenic acid-4,8,12-trimethyl formate (FO11), Ingenol-20-myristinate (FD96) might target with proteins associated with liver cancer. Furthermore, PI3K-Akt signaling pathway and MAPK signaling pathway might be the key pathways of the treatment of liver cancer. In addition, the interaction mode of these active components with nuclear receptor coactivator 2 (3up3) was analyzed.