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In our work, a multi-layer topological insulator (TI) Bi2Se3 thin film was prepared by the chemical vapor deposition method (CVD), and its saturable absorption and damage characteristics were experimentally studied. The results show that when the wavelength is 1064 nm, the saturable absorption parameters of TI: Bi2Se3 film, including modulation depth αs, non-saturable loss αns, and saturation power intensity Isat, increase with the increase in film thickness, and the damage threshold is inversely proportional to the film thickness. The thicker the film layer, the lower the damage threshold. Among them, modulation depth αs is up to 51.2%, minimum non-saturable loss αns is 1.8%, maximum saturation power intensity Isat is 560.8 kW/cm2, and the damage threshold is up to 909 MW/cm2. The influence of the controllable thickness of TI: Bi2Se3 film on passive Q-switching and mode-locking performance of laser is discussed and analyzed when TI: Bi2Se3 film is prepared by the CVD method as a saturable absorber (SA). Finally, the performance of TI: Bi2Se3 thin film applied to nanosecond laser isolation at the 1064 nm band is simulated and analyzed. It has the natural advantage of polarization independence, and the maximum isolation can reach 16.4 dB. [ABSTRACT FROM AUTHOR]

为了提高麻疯树种子的开发利用价值，采用体外抗氧化实验对麻疯树籽仁/壳乙醇提取物抗氧化活性进行了研究。分别以麻疯树种子中的籽仁和籽壳为原料，经75%乙醇提取，在对提取物主要成分进行分析的基础上，以VE为阳性对照，测定两种提取物对自由基（DPPH自由基、ABTS+自由基、羟自由基和超氧自由基）的清除能力、还原能力以及抑制亚油酸自氧化能力。结果表明：麻疯树籽仁/壳乙醇提取物中多糖类物质总含量分别为47.67%和52.21%，酮类物质总含量分别为0.774%和 4.22%，麻疯树籽壳乙醇提取物中还含有0.30%的多酚类物质；麻疯树籽仁/壳乙醇提取物均具有一定的抗氧化活性，其中籽壳乙醇提取物对DPPH自由基、ABTS+自由基、羟自由基、超氧自由基的清除效果较好；麻疯树籽仁/壳乙醇提取物的还原能力和对亚油酸自氧化的抑制能力相对较弱。麻疯树籽壳乙醇提取物的抗氧化活性优于籽仁乙醇提取物，可能与籽壳乙醇提取物中含有较多的黄酮类和多酚类物质有关。 In order to improve the exploitation value of Jatropha curcas seed, the antioxidant activities of ethanol extracts of Jatropha curcas seed kernel and shell were investigated using in vitro antioxidant assays.The kernel and shell of Jatropha curcas seed were extracted by 75% ethanol respectively, and based on the analysis of the main components of the extracts, vitamin E was used as positive control, the scavenging ability on free radical (DPPH radical, ABTS+ radical, hydroxyl radical and superoxide radical ), reducing power and inhibition ability for linoleic acid autoxidation of the two extracts were determined.The results showed that the total content of polysaccharides in the ethanol extract of Jatropha curcas seed kernel/shell was 47.67% and 52.21%, and the total content of ketones was 0.774% and 4.22%, respectively. The ethanol extract of Jatropha curcas seed shell also contained 0.30% polyphenols. The two extracts had certain antioxidant activity, and the extract of seed shell was more effective in scavenging DPPH radical, ABTS+ radical, hydroxyl radical and superoxide radical than that of the extract of seed kernel. The reducing ability and inhibitory ability of linoleic acid autoxidation of the two extracts were relatively weak. The antioxidant activity of the ethanol extract of Jatropha curcas seed shell was better than that of the ethanol extract of Jatropha curcas seed kernel, which may be related to the rich content of flavonoids and polyphenols in the ethanol extract of shell.

Chiral mesostructured NiFe2O4 films (CMNFFs) were synthesized using L -/ D -tyrosine as symmetry-breaking and structure-directing agents through a hydrothermal method. For the first time, chirality induced spin selectivity was directly observed in these ferrimagnetic materials using chirality-dependent magnetic-tip conducting atomic force microscopy (mc-AFM). [ABSTRACT FROM AUTHOR]

This study investigated the relationship between the sense of power and online trolling among college students and the role of self-esteem and moral disengagement in that relationship. Participants were 1 268 college students (females = 61.6%, mean age = 19.94, SD = 2.07 years). The students completed the Sense of Power Scale, the Self-esteem Scale, the Chinese Version of the Moral Disengagement Scale and the Global Assessment of Internet Trolling. The results from the regression analysis and the mediation effect showed that students with a higher sense of power were less likely to engage in online trolling. Moral disengagement mediated the relationship between a sense of power and online trolling to be higher in trolling. The chain mediating effect of self-esteem and moral disengagement between the sense of power and online trolling was significant, so students with a low sense of power also had lower self-esteem and higher moral disengagement. These findings are consistent with structural power theory, which contends that people with a low sense of power do not regard moral standards and are more likely to engage in online trolling. [ABSTRACT FROM AUTHOR]