Jingqi Liu

Rapid identification of both sexes of Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae: Tetrastichinae) : a morphological perspective

The blue gum chalcid, Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae: Tetrastichinae) is a global pest in Eucalyptus plantations. Diverse modes of reproduction (thelytokous and sexual reproduction) are one of the advantages for rapid colonization and outbreak of this species. Understanding the reproductive strategies is advantageous for us to explore the invasive mechanisms. Importantly, how to identify both sexes of the species in the field is a crucial issue before we explore their reproductive strategies. In the current study, indexes of rapid identification of both sexes in L. invasa were studied. Results showed that the obvious differences in both sexes were the antenna and body size. Male wasps have three anelli and four funicular segments, but in females there are four and three segments, respectively. The longer male antennae, which are covered with longer and finer hairs than in the female, was also observed. Body, expansus, head, and gaster sizes of female wasps were significantly larger than the males. These results are an important base not only for exploring the reproductive strategies, but also for controlling L. invasa.

The 573 K and 773 K isothermal sections of the phase diagram of the Pr–Ni–Ti ternary system

Abstract The 573 K and 773 K isothermal sections of the phase diagram of the Pr–Ni–Ti ternary system were investigated by X-ray diffraction, differential thermal analysis, optical microscopy and electron microscopy techniques. The 573 K isothermal section was restricted to the Pr-rich and Ti-rich parts of the Pr–Ni–Ti ternary system. The 773 K isothermal section was restricted to the Ni-rich part of the Pr–Ni–Ti ternary system. The (partial) 573 K isothermal section consists of 6 single-phase regions, 9 two-phase regions, and 4 three-phase regions. The (partial) 773 K isothermal section consists of 9 single-phase regions, 15 two-phase regions and 7 three-phase regions. The maximum solid solubilities of Ti in PrNi 2 , PrNi 3 , Pr 2 Ni 7 , PrNi 5 , and Ni are about 2.5 at.% Ti, 1.5 at.% Ti, 1.0 at.% Ti, 2.0 at.% Ti, and 7.5 at.% Ti at 773 K, respectively. The solid solubilities of the other single-phase regions were too small to observe. The existence of any ternary compounds was not observed in the two partial ternary isothermal sections. The decomposition of NiTi was not observed in the Ni–Ti binary system or in the Pr–Ni–Ti ternary system.

The isothermal section of the phase diagram of the Dy–Mn–Ni ternary system at 803 K

The isothermal section of the phase diagram of the ternary system Dy–Mn–Ni system at 803 K was investigated by powder X-ray diffraction (XRD), differential thermal analysis (DTA), optical microanalysis and electron probe microanalysis techniques. It consists of 13 single-phase regions, 22 two-phase regions and 10 three-phase regions. At 803 K, the maximum solid solubilities of Mn in Ni, Dy2Ni17, DyNi5, Dy2Ni7, DyNi3, DyNi, Dy3Ni2 and Dy3Ni are about 31at.% Mn, 6 at.% Mn, 5.5 at.% Mn, 3 at.% Mn, 5 at% Mn, 5 at.% Mn, 3 at.% Mn and 1.5 at.% Mn, respectively. The maximum solid solubilities of Ni in Mn, DyMn12 and Dy6Mn23 are about 2.6 at.% Ni, 2 at.% Ni and 4 at.% Ni, respectively. DyMn2 and DyNi2 form a continous solid solution in this system. The binary compounds DyNi4 and Dy4Ni17 were not observed in this work. The existence of any ternary compound was not observed.

Phase relationships in the Yb-Fe-Sb system at 530 °C

Abstract Phase relationships in the Yb-Fe-Sb ternary system at 530 °C were investigated mainly by powder metallurgy and X-ray powder diffraction. Nine binary compounds (Yb 6 Fe 23 , Yb 2 Fe 17 , FeSb, FeSb 2 , YbSb 2 , YbSb, Yb 11 Sb 10 , Yb 4 Sb 3 , and αYb 5 Sb 3 ) and one ternary compound (Fe 4 YbSb 12 ) were confirmed in this system at 530 °C. The homogeneity range of FeSb phase extended from approximately 43at.%Sb to 45at.%Sb, the maximum solid solubility of Sb in Fe phase and Yb in FeSb phase was approximately 3at.%Sb and 1at.%Yb at 530 °C, respectively. Isothermal section of the phase diagram of the Yb-Fe-Sb ternary system at 530 °C consisted of thirteen single-phase regions, twenty-four two-phase regions, and twelve three-phase regions.