The Perilla crop is highly regarded in South Korea, both as a health food and traditional food. However, there is still a lack of Perilla SSR primer sets (PSPSs) for studying genetic variation among accessions of cultivated and weedy types of Perilla crop (CWTPC) from South Korea. In this study, 30 PSPSs were newly developed based on transcriptome contigs in P. frutescens, and 17 of these PSPSs were used to study the genetic diversity, phylogenetic relationships and structure population among 90 accessions of the CWTPC collected from South Korea. A total of 100 alleles were detected from selected 17 PSPSs, with an average of 5.9 alleles per locus. The gene diversity (GD) ranged from 0.164 to 0.831, with an average of 0.549. The average GD values from the cultivated var. frutescens, weedy var. frutescens, and weedy var. crispa, were 0.331, 0.588, and 0.389 respectively. In addition, most variance shown by Perilla SSR markers was within a population (73%). An analysis of the population structure and phylogenetic relationships showed that the genetic relationship among accessions of the weedy var. frutescens and weedy var. crispa is closer than that for the accessions of the cultivated var. frutescens. Based on association analysis between 17 PSPSs and three seed traits in 90 Perilla accessions, we detected 11 PSPSs that together were associated with the seed size and seed hardness traits. Therefore, the newly developed PSPSs will be useful for analyzing genetic variation among accessions of the CWTPC, association mapping, and selection of important morphological traits in Perilla crop breeding programs.

The aim of this paper is to obtain Cu–Sn composite coatings incorporated with PTFE and TiO2 particles, which have superior antiwear and friction reduction properties. Electrodeposition was carried out in a pyrophosphate electrolyte, and the electrochemical behavior of the plating solutions was estimated. PTFE emulsion and TiO2 sol were prepared and used, of which the average particle sizes were less than 283 and 158 nm, respectively. Then, four different types of coatings, Cu–Sn, Cu–Sn–TiO2, Cu–Sn–PTFE and Cu–Sn–PTFE–TiO2, were electroplated with a pulsed power supply. Their microstructure, composition, microhardness, corrosion resistance and tribological properties were then analyzed and compared in detail. The results show that both PTFE and TiO2 are able to improve coating structure and corrosion resistance, while they have different effects on hardness and tribological properties. However, the presence of both PTFE and TiO2 in the deposited coating leads to a lower friction coefficient of 0.1 and higher wear and corrosion resistance.

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Nylon fabric was consecutively treated with poly(acrylic acid) (PAA), tetraethylorthosilicate (TEOS), and octadecylamine (OA) to improve its hydrophobicity. We proposed that PAA could be used as a mediator between nylon and OA to provide a high density of the carboxyl moiety. TEOS was used to increase the surface roughness of the nylon fabric by hydrolysis and condensation, and OA was used to reduce the surface energy of the nylon fabric with its long alkyl chains. Both the increase in the surface roughness and the reduction in the surface energy contributed to the improvement of the hydrophobicity of the nylon fabric. The hydrophobicity of the treated nylon fabric was evaluated by the measurement of the water contact angle, water resistance to spray, and hydrostatic pressure. Scanning electron microscopy images showed that the surface roughness of the nylon fabric was significantly increased by treatment with TEOS. The nylon fabric with the PAA/TEOS/OA consecutive treatment exhibited a water contact angle of 1258, a resistance to water spray of 90, and a hydrostatic pressure of 275 mm. It was interesting to find that the PAA/TEOS/OA consecutive treatment slightly enhanced the wrinkle recovery but had no apparent effects on the degree of whiteness and the breaking strength of the nylon fabric.

Purpose The purpose of this paper is to improve binding force between the coating and the steel substrate by using chemical modification on the steel surface; at the same time, it can also increase the corrosion resistance of the coating. Design/methodology/approach The main components of the conversion film include tannic acid, sodium molybdate and silane coupling agent KH560. After the preparation was completed, the samples were tested and analyzed, including surface morphology, conversion film components, bonding force with organic resins and corrosion resistance. Finally, it drew a conclusion that the conversion film can greatly improve the bonding strength of the steel substrate and epoxy resin. Findings When the content of tannic acid is 4 g/L meanwhile the content of KH560 is 20 g/L, the conversion film has the strongest binding force with epoxy resin, from 2.15 Mpa of untreated steel to 4.60 Mpa, growth of 140 per cent. At the same time, the resulting conversion film also improves the corrosion resistance of the steel surface by a small margin. Originality/value A method of enhancing the bond between an epoxy coating and steel is provided. Verify the mechanism of this method.