Recycling of aluminum alloy scrap obtained from delaminated fibre metal laminates (FMLs) was studied through high temperature refining in the presence of a salt flux. The aluminum alloy scrap contains approximately ...Recycling of aluminum alloy scrap obtained from delaminated fibre metal laminates (FMLs) was studied through high temperature refining in the presence of a salt flux. The aluminum alloy scrap contains approximately mass fraction w(Cu) = 4.4%, w(Mg) = 1.1% and w(Mn) = 0.6% (2024 aluminum alloy). The main objective of this research is to obtain a high metal yield, while maintaining its original alloy compositions. The work focuses on the metal yield and quality of recycled A1 alloy under different refining conditions. The NaCI-KC1 salt system was selected as the major components of flux in the A1 alloy recycling. Two different flux compositions were employed at NaC1 to KC1 mass ratios of 44:56 and 70:30 respectively, based on either the euteetic composition, or the European preference. Different additives were introduced into the NaCI-KC1 system to study the effect of flux component on recycling result. Although burning and oxidation loss of the alloying elements during re-melting and refining take place as the drawbacks of conventional refining process, the problems can be solved to a large extent by using an appropriate salt flux. Experimental results indicate that Mg in the alloy gets lost when adding cryolite in the NaCI-KC1 salt system, though the metal yield can reach as high as 98%. However, by adding w(MgF2) = 5% into the NaCI-KC1 salt system (instead of using cryolite) all alloying elements were well controlled to its original composition with a metal yield of almost 98%.展开更多
The principal component analysis (PCA) is one of the most celebrated methods in analysing multivariate data. An effort of extending PCA is projection pursuit (PP), a more general class of dimension-reduction techn...The principal component analysis (PCA) is one of the most celebrated methods in analysing multivariate data. An effort of extending PCA is projection pursuit (PP), a more general class of dimension-reduction techniques. However, the application of this extended procedure is often hampered by its complexity in computation and by lack of some appropriate theory. In this paper, by use of the empirical processes we established a large sample theory for the robust PP estimators of the principal components and dispersion matrix.展开更多
基金the Royal Netherlands Academy of Science and Arts(KNAW)(No.10CDP026)the National Outstanding Young Scientist Foundation of China (No.50825401)the National Natural Science Foundation of China(No.50821003)
文摘Recycling of aluminum alloy scrap obtained from delaminated fibre metal laminates (FMLs) was studied through high temperature refining in the presence of a salt flux. The aluminum alloy scrap contains approximately mass fraction w(Cu) = 4.4%, w(Mg) = 1.1% and w(Mn) = 0.6% (2024 aluminum alloy). The main objective of this research is to obtain a high metal yield, while maintaining its original alloy compositions. The work focuses on the metal yield and quality of recycled A1 alloy under different refining conditions. The NaCI-KC1 salt system was selected as the major components of flux in the A1 alloy recycling. Two different flux compositions were employed at NaC1 to KC1 mass ratios of 44:56 and 70:30 respectively, based on either the euteetic composition, or the European preference. Different additives were introduced into the NaCI-KC1 system to study the effect of flux component on recycling result. Although burning and oxidation loss of the alloying elements during re-melting and refining take place as the drawbacks of conventional refining process, the problems can be solved to a large extent by using an appropriate salt flux. Experimental results indicate that Mg in the alloy gets lost when adding cryolite in the NaCI-KC1 salt system, though the metal yield can reach as high as 98%. However, by adding w(MgF2) = 5% into the NaCI-KC1 salt system (instead of using cryolite) all alloying elements were well controlled to its original composition with a metal yield of almost 98%.
基金The researcb was partially supported by the National Natural Science Foundation of China under Grant No.19631040.
文摘The principal component analysis (PCA) is one of the most celebrated methods in analysing multivariate data. An effort of extending PCA is projection pursuit (PP), a more general class of dimension-reduction techniques. However, the application of this extended procedure is often hampered by its complexity in computation and by lack of some appropriate theory. In this paper, by use of the empirical processes we established a large sample theory for the robust PP estimators of the principal components and dispersion matrix.