摘要：In this study, cinnamic acid derivatives with pyridine ring were synthesized via Hantzsch reaction in order to expand conjugation system and their antioxidant abilities were tested. According to the evaluation results of their antioxidant properties, compounds 2 and 3 have similar antioxidant activity to prevent DNA from ＊OH- and Cu2＋/GSH induced oxidation, demonstrating that 1,4-dihydropyridine and pyridine nucleus exhibit good resistance to oxidation while the substituents have little effect. In the meantime, the AAPH-induced oxidative DNA damage [AAPH=2,2＇-azobis（2-methylpropionamidine）dihydrochloride] and trapping ABTS＋＊ test show that N--H bond and large conjugation systems are the pivotal parts to improve the activities of antioxidant.

摘要：The degnmming pretreatment mechanism was investigated to improve degnmming performance and the spinnability of degummed fibers. Apocynum was treated with redox system in the degumming pretreatment process and the pretreatment parameters had been optimized, besides the effects of pretreatment on property index of degnmmed apocynum fiber were investigated. The results showed that the redox system degumming process reduced alkali boiling time and had good advantages over the traditional degumming process in extraction rate, single fiber length and strength. SEM was used to test the longitudinal morphology changes of fibers before and after pretreatment. At the same time, pretreatment solution was analyzed by UV spectra and electron paramagnetic resonance spectrometer （ESR）, and its pH value was also tested. The results showed that the pretreatment solution could release acid constantly to keep the stability of the pH which caused the swelling and dissolution of pectic substances in apocynum bast. Meanwhile, pretrcatment solution could activate the free radicals from apocynam bast and reduce the activation energy of non- cellulosic composition in apocynum bast.

摘要：Notably,the cleavage of Sn–C bonds in extreme-ultraviolet photoresists containing Sn-oxygen(oxo)clusters and the generation of free radicals upon exposure lead to the chemical linking of Sn-oxo cores and subsequent solubility *** reactivities and migration patterns of the generated radicals substantially influence patterning outcomes,including sensitivity and ***,two Snoxo clusters,Sn_(4)-Me-C_(10)(with Sn–methyl)and Sn_(4)-Bu-C_(10)(with Sn–butyl),were combined to balance the sensitivity and resolution of photoresists,leveraging the feedback regulation between methyl and butyl free radicals generated from Sn–C bond *** electron beam lithography exposure,sensitive butyl radicals produced by Sn_(4)-Bu-C_(10)initiated reactions within Sn_(4)-Me-C_(10),improving ***,the unstable methyl and bulky adamantyl radicals generated by Sn_(4)-Me-C_(10)quenched the excess butyl radicals,thus improving the resolution and exposure ***,this method leveraging the feedback regulation of free radicals offers new insights into the design of sensitive metal oxide resists with enhanced resolution.

摘要：[Objective] This study aimed to investigate the effects of cigarette auxiliary material parameters on release amounts of tar, CO and free radicals in cigarette mainstream smoke. [Method] The effects of cigarette paper air-permeability, cigarette paper gram weight, filter rod pressure drop and filter tip ventilating strength parameters on the release amounts of tar, CO and free radicals in cigarette mainstream smoke were investigated by single factor experiment and orthogonal experiment. [Result] The cigarette paper air-permeability, filter rod pressure drop and filter tip ventilating strength showed significantly negative correlation with the release amounts of tar, CO and free radicals in cigarette mainstream smoke, to be specific, the cigarette paper air-permeability showed the greatest effect on the release amounts of tar and CO, filter tip ventilating strength showed the greatest effect on the release amounts of gaseous-phase free radicals and particulate-phase free radicals, while cigarette paper gram weight showed relatively slight effect on the release amounts of tar, CO and free radicals. Within the orthogonal experimental range, the optimal program is identified as cigarette paper airpermeability of 70 CU, filter rod pressure drop of 4500 Pa/unit, and filter tip ventilating strength of 60 CU. Compared to the results without optimization, the release amounts of tar, CO and free radicals after optimization were all reduced. [Conclusion] This study laid the foundation for the research of cigarette tar reduction and harm reduction.