Al-based alloys have recently attracted considerable interest as structural materials and light weight materials due to their excellent physical and mechanical properties. For the investigation of the potential of Al-based alloys, a surface porous Al88Cu6Si6 eutectic alloy has been fabricated through a chemical leaching process. The formation and microstructure of the surface porous Al88Cu6Si6 eutectic alloy have been investigated using X-ray diffraction and scanning electron microscopy. The Al88Cu6Si6 eutectic alloy is composed of an α-Al dendrite phase and a single eutectic phase of Al2Cu and α-Al. We intended to remove only the α-Al phase and then the Al2Cu phase would form a porous structure on the surface with open pores. Both acidic and alkaline aqueous chemical solutions were used with various concentrations to modify the influence on the microstructure and the overall chemical reaction was carried out for 24 hr. A homogeneous open porous structure on the surface was revealed via selective chemical leaching with a H2SO4 solution. Only the α-Al phase was successfully leached while the morphology of the Al2Cu phase was maintained. The pore size was in a range of 1~5μm and the dealloying depth was nearly 3μm. However, under an alkaline NaOH, aqueous solution, an inhomogeneous porous structure on the surface was formed with a 5 wt% NaOH solution and the morphology of the Al2Cu phase was not preserved. In addition, the sample that was leached by using a 7 wt% NaOH solution crumbled. Al extracted from the Al2Cu phase as α-Al phase was dealloyed, and increasing concentration of NaOH strongly influenced the morphology of the Al2Cu phase and sample statement.
벼 재배에 있어 강피(Echinochloa oryzicola)와 물피(E. crus-galli)는 가장 경합력인 큰 문제 잡초로 알려졌는데 최근 제초제 저항성 피의 증가로 피의 효과적인 방제가 새로운 화두가 되고 있다. 저항성 피의 효과적인 방제를 위해서는 제초제 저항성 여부의 조기진단을 통한 대체 제초제를 이용한 방제가 필요하다. 따라서 본 연구는 제초제 저항성 피의 효과적인 진단을 위해 피노믹스 기반의 비파괴 조기진단법을 개발하고자 수행되었다. Acetolactate synthase (ALS) 저해제, acetyl CoA carboxylase (ACCase) 저해제, photosystem II (PSII) 저해제에 저항성 및 감수성인 각각의 강피, 물피, 열대피(E. colona)를 3-4엽기까지 온실조건에서 생육한 후 해당 제초제를 다양한 약량으로 경엽살포한 후 일정한 시간간격으로 잎의 형광반응을 조사하였다. 그 결과 PSII 저해제 저항성 피는 제초제 경엽처리후 3-4일 이내 저항성 피의 진단이 가능하였으며, ALS 저해제 및 ACCase 저해제 피의 경우는 7-8일 이내 저항성 피의 진단이 가능하였다. 따라서 가장 보편적으로 저항성 잡초의 진단에 사용하는 whole plant assay의 소요시간 20-30일에 비해 잎의 형광반응 측정을 통해 저항성 잡초의 진단 소요시간을 혁신적으로 단축할 수 있었다.