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The mineralogical composition,microstructure and TiO2 distribution rule of low titanium-containing blast furnace slags after water cooling and air cooling were investigated by X-ray diffraction,polarization microscopy and scanning electron microscopy.The results show that main mineralogical compositions in these slags are all vitreous,gehlenite,perovskite and merwinite,but the contents of mineral components in the two kinds of slags have much larger differences. The average contents of gehlenite and perovskite in the air-cooled slag are 62.5% and 12.5%,which are 2.27 and 1.92 times as large as those in the water-cooled slag,respectively.The content of vitreous in the air-cooled slag is less than a third of that in the water-cooled slag. The mineralogical microstructure of the water-cooled slag is pretty different from that of the air-cooled slag. Gehlenite in the water-cooled slag is dentate,but in the watercooled slag it is feathery and needle-shaped,and its grain size is smaller. Perovskite forms as star points and dendritic in the watercooled slag and the air-cooled slag,respectively. Merwinite is spindle-shaped both in the water-cooled slag and the air-cooled slag. It could be concluded that TiO2 in the water-cooled slag mainly distributes in perovskite,vitreous glassy and gehlenite,but TiO2 in theair-cooled slag mainly distributes in perovskite and gehlenite,and the distribution ratio of TiO2 in the air-cooled slag is 8.41% higher than that in the water-cooled slag. Air cooling is more beneficial to increase TiO2 content in perovskite.

Well diffusion method was used to evaluate the antibacterial activity of Eucalyptus camaldulensis, while the antifungal effect was assessed by calculating the reduction percent in the radial growth of mycelia. The inhibition zones exerted by E. camaldulensis crude extracts varied significantly (p ≤ 0.01). The capsule crude extract (acetone 30%) highly inhibited the growth of Acinetobacter baumannii (35 mm clear zone). The highest antifungal activity was against Rhizopus stolonifer with a reduction percent in its radial growth reached to 96%. The bacterial MICs ranged from 20 to 0.5 mg/mL against Escherichia coli and Bacillus subtilis respectively. The MIC values for fungi were between 18 mg/mL (Mucor sp.) and 4 mg/mL (R. stolonifer). Both type and concentration of the solvent greatly affected the antimicrobial potentials of E. camaldulensis. The empty capsule and bud of E. camaldulensis are recognized for the first time as potentially natural resources of effective antimicrobial agents. [ABSTRACT FROM AUTHOR]

The thermal evolution of bimetallic Cu-Ni 343 and 1000 atom nanoclusters of compositions are examined with molecular dynamics simulations using the Sutten-Chen many-body potential function. It is found that the bimetallic clusters melt in two stages, the first transition corresponds to surface melting of the external Cu layers and the second transition corresponds to homogenous melting and takes place in the range of 700 to 900 K.

To face on the growing needs of the campus network resources, TV broadcast system based on campus network has become a simple and effective solution to video resources service over campus for its stability and diversity. With the promotion of campus network performance, application of HD video stream over the campus network has emerged. The characteristics of the multicast technology make the transmission of HD video stream become possible on the campus network. This paper mainly discusses the signal source, the production of HD stream, multicast technology and user terminal etc., and tries to build a feasible campus network HDTV broadcast system. The experience can be used as reference to the construction of an HDTV broadcast system over campus network. [ABSTRACT FROM AUTHOR]

Publishing data for analysis from a microdata table containing sensitive attributes, while maintaining individual privacy, is a problem of increasing significance. Now, the k-anonymity model was proposed for privacy preserving data publication. While focusing on identity disclosure, k-anonymity model fails to protect attribute disclosure to some extent. This paper proposed a new privacy protection model called (p+, α)-sensitive k-anonymity, where sensitive attributes were first partitioned into categories by their sensitivity, and then published the categories that sensitive attributes belong to. Different from previous enhanced k-anonymity models, this model allowed us to release a lot more information without compromising privacy. Experimental results show that this introduced model can significantly reduce the privacy breach. [ABSTRACT FROM AUTHOR]

We study the geometries, stabilities, electronic and magnetic properties of (MgO)n (n=2-10) clusters doped with a single Mn atom using the density functional theory with the generalized gradient approximation. The optimized geometries show that the impurity Mn atom prefers to replace the Mg atom which has low coordination number in all the lowest-energy MnMgn-1On (n=2-10) structures. The stability analysis clearly represents that the average binding energies of the doped clusters are larger than those of the corresponding pure (MgO)n clusters. Maximum peaks of the second order energy differences are observed for MnMgn-1On clusters at n=6, 9, implying that these clusters exhibit higher stability than their neighboring clusters. In addition, all the Mn-doped Mg clusters exhibit high total magnetic moments with the exception of MnMgO2 which has 3.00 μB. Their magnetic behavior is attributed to the impurity Mn atom, the charge transfer modes, and the size of MnMgn-1On clusters. [ABSTRACT FROM AUTHOR]

Based on the dynamic panel data of 14 China banks from 1995 to 2004 ,the paper studies the relationship between the Bank concentration and efficiency. The evidence shows that concentration boosts bank efficiency. Meanwhile, the relationship between the loadable funds and bank efficiency is significantly positive, and the relationship between the total capital, the equate capital and bank efficiency is significantly negative, and the level of significance reduces except the bank concentration. Using the panel var, the paper finds all of the level of significance increase, while the coefficiency of regression decreases, and the net profit is positive to efficiency. Except the deposit funds, other variables are the "statistical " reasons for efficiency. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are used to investigate the shape and structure evolution of single platinum clusters of cubic and spherical shape containing 256 and 260 atoms, respectively, deposited on a static graphite substrate. The evolution is monitored at variable temperature, and as a function of metal–substrate interactions at constant temperature. The Pt–Pt interactions are modelled with the many-body Sutton–Chen potential, whereas a LennardJones potential is used to describe the Pt–C interactions. Heating and cooling curves calculated between 200K and 1800K are used to determine solid–solid and solid–liquid transitions. Structural changes are detected through analyses of density profiles and diffusion coefficients. A clear analogy is observed between temperature-induced wetting phenomena and those resulting from enhancement of the metal–substrate interactions. [ABSTRACT FROM AUTHOR]