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Polyamide-6 (PA) is a popular textile polymer having desirable mechanical and thermal properties, chemical stability, and biocompatibility. However, PA nanofibers are prone to bacterial growth and user discomfort. ε-Poly-L-lysine (PL) is non-toxic, antimicrobial, and hydrophilic but lacks spinnability due to its low molecular weight. Given its similar backbone structure to PA, with an additional amino side chain, PL was integrated with PA to develop multifunctional nanofibers. This study explores a simple, scalable method by which to obtain PL nanofibers by utilizing the structurally similar PA as the base. The goal was to enhance the functionality of PA by addressing its drawbacks. The study demonstrates spinnability of varying concentrations of PL with base PA while exploring compositions with higher PL concentrations than previously reported. Electrospinning parameters were studied to optimize the nanofiber properties. The effects of PL addition on morphology, hydrophilicity, thermal stability, mechanical performance, and long-term antimicrobial activity of nanofibers were evaluated. The maximum spinnable concentration of PL in PA-based nanofibers resulted in super hydrophilicity (0° static water contact angle within 10 s), increased tensile strength (1.02 MPa from 0.36 MPa of control), and efficient antimicrobial properties with long-term stability. These enhanced characteristics hold promise for the composite nanofiber's application in medical and protective textiles. [ABSTRACT FROM AUTHOR]

Based on the traditional black tea processing technology, the hot air withering process was used to replace the traditional indoor natural withering process on the basis of the traditional black tea processing technology. The effects of four hot air withering processes of 35 °, 45 °, 55 ° and 65 ° on the quality of summer and autumn black tea were studied and analyzed from three aspects of sensory quality, taste quality and aroma quality. The results show that compared with 25 ° traditional indoor natural withering black tea, the comprehensive sensory quality of black tea processed by 45 ° hot air withering process was better. The color of dry tea was dark brown and moist, the soup color was red and bright, the taste was mellow and refreshing, and the quality characteristics was sweet aroma. At the same time, the contents of tea polyphenols, gallic acid, EGCG, theaflavins, thearubigins and the ratio of the sum contents of theaflavins and thearubigins to the content of theabrownins (TFRB) significantly increased (P<0.05), while the content of soluble sugar decreased significantly (P<0.05). The types of aroma quality components increased, among which alcohols accounted for the highest proportion (70.47%), and the relative contents of alcohols, ketones and esters increased significantly (P<0.05), while pyrroles and aldehydes decreased significantly (P < 0.05). And the aroma components with flower and fruit aroma such as trans-3-hexenol, 2,3-dihydro-2,2,6-trimethylbenzaldehyde and α-ionone were detected. This shows that hot air withering with appropriate temperature is conducive to improving the quality of black tea, which can be applied to the production practice of improving the quality of black tea in summer and autumn. [ABSTRACT FROM AUTHOR]