Conventional chemical ecology approach for identification of semiochemicals from natural sources is based on isolation of active ingredients after fraction and bioassay. Instead, we identify potential semiochemicals using reverse chemical ecology approach. In this way, we discovered an odorant receptor (CquiOR136) for DEET, which was not know how and why it work. Additionally, we identified a link between this synthetic repellent and methyl jasmonate, thus suggesting that DEET might work by mimicking defensive methyl jasmoante from plant. Moreover, we serendipitously found that a receptor, CquiOR36, responded to an old sample of nonanal in ethanol. Careful investigation led us to identify the active ligand as acetaldehyde (derived from ethanol) from “contaminants” in the old nonanal sample. We explored that acetaldehyde in a wide range of dose both attracts gravid mosquito and stimulate them to lay eggs in oviposition trays.

An infiltration technique using W-Cu composite powder has been developed to enhance microstructural uniformity of W-Cu pseudo-alloy. W-Cu composite powder, manufactured by reduction from WO3 and CuO powder mixtures, were blended with W powder and then cold iso-statically pressed into a cylindrical bar under 150 MPa. The pressed samples were pre-sintered at 1300 oC for 1 hour under hydrogen to make a skeleton structure. This skeleton structure was more homogeneous than that formed by using W and Cu powder mixtures. The skeleton structures were infiltrated with Cu under hydrogen atmosphere. The infiltrated W-Cu pseudo-alloy showed homogeneous microstructure without Cu rich region.

A new tungsten heavy alloy with hybrid structure was manufactured for the kinetic energy penetrator. The tungsten heavy alloy is composed of two parts: core region is molybdenum added heavy alloy to promote the self-sharpening; outer part encompassing the core is conventional heavy alloy to sustain severe load in a muzzle during firing. From ballistic test, it was found that the penetration performance of the hybrid structure tungsten heavy alloy is higher than that of conventional heavy alloy. This heavy alloy is thought to be very useful for the penetrator in the near future.