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In this work MmNi3.5(CoMnAl)1.5 and Mg were mechanically alloyed to prepare composite hydrogen storage alloys. The microstructural variation of the alloy resulted from the mechanical alloying was characterized by X-ray diffraction, SEM and TEM analysis. It was found that solid state reaction occurred between MmNi3.5(CoMnAl)1.5 and Mg components, resulting in Mm2Mg17 phase formation. The alloy obtained by ball milling contains homogeneously distributed Mg, MmNi3.5(CoMnAl)1.5 and Mm2Mg17 phases of nanometer size. It was also found that Mg2Ni was formed after the mechanically alloyed samples were annealed. The mechanism of the reaction has been proposed based on the estimation of the heat of formation using Miedema's theory and is in accordance with the experiment result of lattice constant measurement of ball milled sample and its structure variation during annealing. [ABSTRACT FROM AUTHOR]

Ni-P deposits of amorphous, nanocrystalline, and mixed structures were prepared by electroless deposition. The three deposits were hypoeutectic Ni-P alloys with different P concentrations. The overall transformation sequences of the deposits during post-deposition annealing were investigated using differential scanning calorimetry, x-ray diffraction, and transmission electron microscopy. It was found that there existed three heat-release peaks in a mixed-structure deposit during annealing. The first peak came from the precipitation of Ni nanocrystallites from an amorphous matrix, the second peak resulted from the decomposition of the retained amorphous matrix into Ni + Ni3P having a composition close to the eutectic point, and the third peak, newly found in hypoeutectic Ni-P alloys, was assumed to be caused by both grain growth and the precipitation of Ni3P from as-deposited supersaturated Ni(P) nanocrystals interspersed within the amorphous matrix. By comparing the transformation sequences of the amorphous deposit with that of the nanocrystalline deposits, it was concluded that the transformation sequence of the mixed-structure deposit was a superimposition of those of both the amorphous and nanocrystalline deposits. [ABSTRACT FROM AUTHOR]

In this article, endosperm starch grains of eleven lines in multiplasmic maize were studied by scanning electron microscope. The results show that different cytoplasm has different effects on the characters of starch grain. The starch grains of three sweet corn cytoplasmic lines (su1, sh2, btl) are mainly spherical and packed tightly, which means they have some degree of similarity. While the grains of four cytolasmic male sterility lines (T, S, C, 21A) are mostly irregular and packed loosely except (T) Mo17, in which grains are tightly packed. The average diameter of these eleven varieties is ranged from 9.78 microns to 14.69 microns. Through the study of endosperm starch grain shape and size, we tried to explore the relationship between the property of starches and the quality of seeds. And this will significantly prompt the development of maize genetics and breeding.