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Menthol has been employed recently as important temporary consolidant for conservation of cultural heritages. In this paper, a phase field solidification model is proposed and numerical simulations are conducted to investigate the solidification mechanism of menthol. Simulations provide not only the phase transition of menthol during solidification in consistent with experiment, but also how solidification reaction and evolution of heat are mutually interacted. Solidification leads to liberation of latent heat, contributes to the high temperature in un-solidified core and in turn retards solidification. In addition, size effects on solidification quality and mechanical strength are investigated. During solidification, tensile stresses affect solidification and lead to micro defects which are described using relaxation strain in this manuscript, result in size dependent volumetric contraction as well as residual stress after solidification. Operating solidification in smaller size geometries would help lower down the internal stresses and relaxation strain, resulting in denser products of higher mechanical strength. Therefore, multistep casting procedure is suggested rather than one step casting in real consolidations using menthol.

To investigate the effects of embryo abortion on fruit size and weight, fruit quality, chlorophyll, carotenoid, anthocyanin, flavonoid, and total polyphenols, the seeded fruit of mango (Mangifera indica L.) cultivar 'Guifei' were compared at the ripe stage. Seedless fruit had significantly smaller fruit size and lower fruit weight than seeded fruit in the cultivar. The experimental results suggested that embryo abortion at early stages of fruit ripening did not affect the concentration of total polyphenols in the pulp of matured fruit at green color or yellow color stages. However, the chlorophyll level decreased with ripening, lower in the abortion mango than in the normal mango. Carotenoid content increased throughout yellow stage and was significantly higher in the normal fruit compared to the abortion fruit. The concentrations of flavonoid were lower in the abortion fruit compared with normal fruit in the same color fruit. The expression of PSY and PDS was increased from green to yellow in abortion and normal mango. Expression of ANS and DFR was higher in the green color mango, in different development stages, and lower at the abortion stage in the yellow mango.

Commercially pure iron (CP Fe) was manufactured by equal channel angular pressing (ECAP) to explore the effects of annealing temperature on the deformation behavior of the materials with BCC structure. The effect of annealing temperature on the room-temperature (RT) compressive deformation behavior, sub-structures, and surface damage characteristics of the ECAP Fe were systematically studied. The results showed that as the annealing temperature increased, grain size of the ECAP Fe significantly increased, the dislocation density decreased, the grain boundaries were clear, and the grain structure was composed of equiaxed grains and sub-grains. When the ECAP Fe was annealed at temperatures below 673 K, the strength and flow stability under uniaxial compression were significantly improved. Better uniform deformation ability and grain boundary coordinated deformation ability were shown with only small-scale shearing on the compression surface. Secondary shear lines with a cross-distribution and a small amount of discontinuous fine micro-shear cracks appeared near the micro-shear bands, but large-scale shear bands were not observed in the compressed annealed samples. When annealed above 673 K, the strength and flow stress promptly decreased, and a long strain hardening stage occurred. Large-scale shear cracks appeared on the compressed surface, which was seriously damaged. The deformation mechanisms under different annealing effects are further discussed. Use of appropriate annealing temperature is necessary to improve the coordinated deformation of the grain boundaries. Additionally, the mechanical properties of the material will also diminish the damage level.

A deception jamming method is proposed, which can be used by a team of UAVs to deceive air defense radar network. To make the phantom tracks undistinguishable from the tracks of the true targets, the position geometry of radars and UAVs was studied, and the analytical expression of relationships between the motion of the UAVs and that of the phantom tracks have been derived, which can be used to precisely arrange the UAVs' flight path and control the jammers' jamming strategy. Mathematic analysis and simulation results show that using N UAVs can generate at most Nx(N-1) coherent false targets, which can deceive the radar network and form trajectories in the fusion centre. (4 pages)