Silica fume, fly ash and nano-fiber mineral materials (NR powder) are employed to incorporate into cement-based materials. According to the grain grading mathematical model of cement-based materials, two packing syste...Silica fume, fly ash and nano-fiber mineral materials (NR powder) are employed to incorporate into cement-based materials. According to the grain grading mathematical model of cement-based materials, two packing systems, namely, spherical grading system and nano-fiber reinforced system were designed. Properties and interfacial microstructure of the two systems were studied according to secondary interface theory. It was shown that nano-fiber mineral materials can improve the grain grading of the admixture, increase the density of the system, improve the microstructure of the interface and the hardened paste, and enhance the uniformity of cement-based materials mixed with composite micro-grains and greatly increase their wearable rigidity and flexure strength. In this paper, two kinds of interface models, including spherical grain model and nano-fiber reinforced interface model of the cement-based materials mixed with composite micro-grains, were brought forward.展开更多
GaN microcrystalline grains were grown by hot-wall chemical vapor deposition on Si(111)substrate.These grains with diameters of 2-4 μm were detected by scanning electron microscopy.X-ray diffraction,Fourier transform...GaN microcrystalline grains were grown by hot-wall chemical vapor deposition on Si(111)substrate.These grains with diameters of 2-4 μm were detected by scanning electron microscopy.X-ray diffraction,Fourier transformation infrared transmission spectroscopy and photoluminescence were used to analyze the structure, composition and the optical properties of the samples.The results show that the microcrystalline grains are hexagonal wurtzite GaN,and the property of the grains was greatly affected by the growth time.展开更多
文摘Silica fume, fly ash and nano-fiber mineral materials (NR powder) are employed to incorporate into cement-based materials. According to the grain grading mathematical model of cement-based materials, two packing systems, namely, spherical grading system and nano-fiber reinforced system were designed. Properties and interfacial microstructure of the two systems were studied according to secondary interface theory. It was shown that nano-fiber mineral materials can improve the grain grading of the admixture, increase the density of the system, improve the microstructure of the interface and the hardened paste, and enhance the uniformity of cement-based materials mixed with composite micro-grains and greatly increase their wearable rigidity and flexure strength. In this paper, two kinds of interface models, including spherical grain model and nano-fiber reinforced interface model of the cement-based materials mixed with composite micro-grains, were brought forward.
文摘GaN microcrystalline grains were grown by hot-wall chemical vapor deposition on Si(111)substrate.These grains with diameters of 2-4 μm were detected by scanning electron microscopy.X-ray diffraction,Fourier transformation infrared transmission spectroscopy and photoluminescence were used to analyze the structure, composition and the optical properties of the samples.The results show that the microcrystalline grains are hexagonal wurtzite GaN,and the property of the grains was greatly affected by the growth time.
