Papers by Author: Ru Yang

Abstract: Network spoofing attacks are very specialized attacks, and network security managers brought a severe test. In this paper, through the analysis of the ARP protocol works, it discusses ARP protocol ARP virus are two common attacks from the IP address to the security risks that exist in the physical address resolution process, and then analyzes in detail, and then introduces the ARP Find virus source and virus removal methods, and finally putting forward effective measures to guard against ARP virus.

Abstract: CaTiO3:Pr3+ was prepared by high temperature solid state reaction and measured by SEM, XRD, excitation and emission spectra. The samples obtained possessed orthorhombic crystal structure of CaTiO3, belonging to Pbnm space group. Excitation spectra of the samples were broad band, their peaks and shoulder peaks were located at about 335nm, 379nm respectively. Emission spectra were single narrow band, emission peaks were located at about 602nm, corresponding to emission of 1D2→3H4 of Pr3+ion. The addition of Eu3+and Dy3+ as co-activator led phosphorescent intensity to greatly enhance, the addition of AgNO3 as ion compensator made the samples material pink and vibrant.

Abstract: YAG precursors were co–precipitated from a mixed solution of aluminum and yttrium nitrates using urea as precipitant. After being washed by ethanol several times, the gel–like precursor was dispersed in absolute ethanol to form suspended liquid. The mixture was placed into a high–pressure autoclave, which followed by heating ethanol to supercritical state (Tc > 243°C and Pc > 6.3Mpa). The precursor dried via supercritical ethanol fluid technique was sintered at different temperature according to requirement. The phase transformation, composition and micro–structural features of the products were characterized by XRD, TG/DSC, BET and TEM techniques. It was found that after supercritical ethanol fluid drying the precursor was well dispersed, uniform and caused better sinterability of the resultant YAG powder. XRD results indicated that the precursor was partial crystalline and the pure phase YAG can be obtained at 1200°C calcinated for 2h. TG/DSC revealed the formation process of YAG phase. The averaged size of YAG nanocrystalline powder was 30–40nm and well dispersed according to TEM.

Abstract: High concentrated hydrochloric/nitric/sulfuric acid were used to dissolve Ti(OH)4 produced with TiOSO4. It was found that, titania, from pure rutile phase to anatase-rutile mixed phase to pure anatase phase have been synthesized at low temperature in liquid media through controlling the hydrolyzation conditions. The phase composition and the special surface area of nanometer titania powder were characterized by means of XRD and BET. The K-edge fine structure of Ti atom sites of rutile TiO2 was investigated with grazing incidence reflection mode XAFS (EXAFS and XANES) spectroscopy. The well-crystal rutile TiO2 with fine particle size and high specific surface (above200m2/g) was formed at low temperature below 80°C, while the anatase TiO2 was formed at higher temperature in hydrochloric or nitric acid solution. But in sulfuric acid solution the crystal phase was always anatase at any temperatures. The EXAFS and XANES result showed that the order of the lattice, the coordination numbers of the Ti atom for the first shell, the second shell and the third shell as well as the relative intensity of K-preedge three peaks increased with the increase of the rutile TiO2 nanoparticle size.