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A comparative study of bronze coatings on steel produced by plasma and cold metal transfer wire-arc depositing was carried out. The microstructure, interface characteristics, hardness, and shear bond strength of bronze deposits were investigated. Cold metal transition (CMT) deposition presented lesser penetration cracks and lower dilution than that of plasma arc deposition (PAD). The interfacial bonding of CMT deposits appeared as diffusion bonding characteristics, whereas PAD achieved a good metallurgical bond. Plasma arc deposited specimens showed more severe penetrating cracks and less CMT due to the difference of dilution rate. As heat input increased, microstructure of CMT and PAD deposited layer transformed from α-Cu + spherical or dendritic Fe-rich phase to massive Fe-rich phase + ε-Cu. The volume percentage of α-Cu +γ1 in CMT deposits was observed higher than that of PAD, and Fe-rich phase in the PAD was significantly higher than that of CMT, leading in a significant increase of microhardness of PAD. Interfacial bonding strength of PAD under high heat input was much higher than that of CMT. [ABSTRACT FROM AUTHOR]

A detailed study of the pulsed triple-wire gas indirect arc (TW-GIA) welding process based on the arc deflection effect was carried out in this article. The arc anode deflection mechanism, the effect of pulse parameters on weld forming and efficient welding process were systematically studied. The results showed that the special annular electric field and the non-uniform magnetic field were the main reasons for the indirect arc deflection to the anode. When the main wire acted as the anode and the side wires acted as the cathode, the two indirect arcs would deflect synchronously toward the main wire and couple into one arc with high energy density and larger arc stiffness. The arc length and welding depth can be controlled by adjusting the pulse parameters. A stable and efficient single-pass pulsed TW-GIA welding process for a 10 mm Q235 steel plate was developed. The fusion of the side wall of the welded joint was very good, the average tensile strength reached 471.2 Mpa and all joints broke in the base metal. [ABSTRACT FROM AUTHOR]

The complete genome sequence of a double-stranded RNA (dsRNA) mycovirus that was isolated from Alternaria solani strain DT-10 causing potato foliar disease was determined. The virus, designated as "Alternaria solani chrysovirus 1" (AsCV1), has four dsRNA segments (dsRNA 1-4) with a length of 3600 bp, 3128 bp, 2996 bp, and 2714 bp, respectively. The RNA-dependent RNA polymerase (RdRp, 1084 amino acids [aa]), putative capsid protein (905 aa), alphachryso-P3 (835 aa), and alphachryso-P4 (729 aa) were encoded by dsRNA1, dsRNA2, dsRNA3, and dsRNA4, respectively, which had the highest sequence identity of 41.77%-72.38% to their counterparts in Helminthosporium victoriae virus 145S (HvV145S) of the genus Alphachrysovirus, family Chrysoviridae. Moreover, the 5′-untranslated regions (UTRs) of AsCV1 dsRNA 1-4, which contained several unique inserts (3-37 bp) and deletions (5-64 bp), shared 51.65%-68.01% identity with those of HvV145S. Phylogenetic analysis based on RdRp sequences showed that AsCV1 clustered the most closely with HvV145S. Considering its distinct host specificity, the low sequence similarity of its encoded proteins to those of other viruses, the unusual features of the 5′-UTRs of its dsRNA 1-4, and the phylogenetic position of its RdRp gene, AsCV1 should be considered a member of a new species in the genus Alphachrysovirus. To the best of our knowledge, this is the first alphachrysovirus identified from phytopathogenic A. solani. [ABSTRACT FROM AUTHOR]

A double-stranded RNA (dsRNA) segment was identified in Rhizoctonia solani anastomosis group (AG)-2-2IIIB, the primary causal agent of Rhizoctonia crown and root rot of sugar beet. The dsRNA segment represented the genome replication intermediate of a new mitovirus that was tentatively designated as "Rhizoctonia solani mitovirus 39" (RsMV-39). The complete sequence of the dsRNA was 2805 bp in length with 61.9% A+U content. Using either the fungal mitochondrial or universal genetic code, a protein of 840 amino acids containing an RNA-dependent RNA polymerase (RdRp) domain was predicted with a molecular mass of 94.46 kDa. BLASTp analysis revealed that the RdRp domain of RsMV-39 had 43.55% to 72.96% sequence identity to viruses in the genus Mitovirus, and was the most similar (72.96% identical) to that of Ceratobasidium mitovirus A (CbMV-A). Phylogenetic analysis based on RdRp domains clearly showed that RsMV-39 is a member of a distinct species in the genus Mitovirus of the family Mitoviridae. This is the first full genome sequence of a mycovirus associated with R. solani AG-2-2IIIB. [ABSTRACT FROM AUTHOR]