ABSTRACT
Magnesium-based amorphous alloys have aroused broad interest in being applied in marine use due to their merits of lightweight and high strength. Yet, the poor corrosion resistance to chloride-containing seawater has hindered their practical applications. Herein, we propose a new strategy to improve the chloride corrosion resistance of amorphous Mg65Cu15Ag10Gd10 alloys by engineering atomic-to-nano scale structural homogeneity, which is implemented by heating the material to the critical temperature of the liquid-liquid transition. By using various electrochemical, microscopic, and spectroscopic characterization methods, we reveal that the liquid-liquid transition can rearrange the local structural units in the amorphous structure, slightly decreasing the alloy structure's homogeneity, accelerate the formation of protective passivation film, and, therefore, increase the corrosion resistance. Our study has demonstrated the strong coupling between an amorphous structure and corrosion behavior, which is available for optimizing corrosion-resistant alloys.
ABSTRACT
Four basidiomycetous yeast strains (Y13-1(T), Y2-1, Y6-3 and Y8-2) were isolated from soil and bark collected from an apple orchard in Tai'an, Shandong province, PR China. Phylogenetic analysis based on 26S rRNA gene D1/D2 domains and ITS regions revealed that these novel strains were located in the Kwoniella clade in the class Tremellomycetes and were closely related to Cryptococcus cuniculi and Kwoniella heveanensis, but were clearly distinct from these species. Therefore, it is proposed that the new strains represent a novel species, Kwoniella shandongensis sp. nov., with the type strain Y13-1(T)(=CGMCC 2.04458(T)=CBS 12478(T)). The MycoBank number for the novel species is MB 564868.
Subject(s)
Basidiomycota/classification , Malus/microbiology , Phylogeny , Basidiomycota/genetics , Basidiomycota/isolation & purification , China , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Molecular Sequence Data , Mycological Typing Techniques , Plant Bark/microbiology , RNA, Ribosomal/genetics , Sequence Analysis, DNA , Soil MicrobiologyABSTRACT
Three teleomorphic ascomycetous yeast isolates (TA11TR-1(T), TA11TR-4 and TA11TR-6) from orchard soil from Tai'an, Shandong province, China, were shown to represent a novel species within the genus Kazachstania based on phenotypic characterization and sequence analyses of the 18S rRNA gene, internal transcribed spacer (ITS) regions and 26S rDNA gene D1/D2 domain. The name Kazachstania taianensis sp. nov. (type strain TA11TR-1(T) =AS 2.4160(T) =CBS 11405(T)) is proposed. K. taianensis sp. nov. clustered in a branch together with Kazachstania sinensis, Kazachstania naganishii and the Kazachstania telluris complex with moderate bootstrap support in the neighbour-joining tree reconstructed from combined 18S and D1/D2 sequences. The novel species possessed unusual ITS 1 (338 bp) and ITS 2 (488 bp) sequences. The total length of the ITS-5.8S rDNA gene region of the species was 983 bp, being much longer than those of other ascomycetous yeast species described so far.
Subject(s)
Ascomycota/genetics , Ascomycota/classification , Ascomycota/isolation & purification , China , Fruit , Karyotyping , Molecular Sequence Data , Phylogeny , RNA, Fungal/genetics , RNA, Ribosomal, 16S/genetics , Soil Microbiology , Species Specificity , TreesABSTRACT
According to the conserved amino acid sequence from ethylene receptors in other plants, a pair of degenerate primers was designed and a 657-bp cDNA fragment encoding an ethylene receptor fruit was obtained by RT-PCR from ripening kiwifruit (Actinidia deliciosa cv. Bruno) (Fig. 1). The cDNA fragment encoding 219 amino acids was named Ad-ETR1, and its sequences shared high similarity at both nucleotide and polypeptide level with the sequences from the plants of Arabidopsis, tomato, persimmon, avocado, citrus and peach (Fig. 2, Table 1). Northern blot analysis indicated that the levels of Ad-ETR1 mRNA increased during kiwifruit ripening and reached peak at 144 h after treatment, then dropped immediately. The expression of Ad-ETR1 could be induced by ethylene treatment, while acetylsalicylic acid (ASA) treatment inhibited its expression (Fig. 4). In consistency with the changes of Ad-ETR1 mRNA, ethylene or ASA treatment had marked effects on the kiwifruit ethylene production and fruit softening (Fig. 3). The significance of these results was discussed.
