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The bacteriostatic effect of nanosilve is researching purposes. Five strains from Aspergillus was used as the experimented materials. The concentration of nanosilver is180 mg / L. 0.3% carbendazim and 0.3% chlorothalonil was used as compering bacteriostatic agents. The results was gained that nanosilve has inhibiting on the growth, spore’s germination, and effecting on bacteriostasis ring and shape of the Aspergillus. The bacteriostasis of nanosilve is very better than blank comparing experimert. For the bacteriostdsis of nanosilve on Aspergillus, there is differentation among strains. The bacteriostdsis of carbendaim is better than chlorothdonil. The batteriostdsis of chlorothdonil is very better than nanosilve. The bacteriostdsis principle is that nanosilve disrupts permeation of cell membrance of Aspergillus.

Through a comparative study of the bacteriostatic effect of nanosilver of different species and concentrations against bacteria, it is found that nanosilver have significant bacteriostatic effect against bacteria. Bateriostatic effect of nanosilve 15# against B. thuringiensis is significantly better than E.coli, s. aureus and B. subtillis. The optimal concentrations of 15# for inhabiting E. coli, S. aureus, B. subtillis and B. thuringiensis respectively are: 20 mg/L, 10 mg/L, 1 mg/L, 40 mg/L. nanosilvers of 13#, 14# and 15# have no significant differences in the bacteriostatic effect against E.coli, but are all significantly better than the bacteriostats of lincomycin hydrochloride and streptomycin sulfate. Antibacterial principle of nanosilver is damaging the cell membrane permeability.

This paper uses the yield line theory in plasticity, combined with the static equilibrium method, which derives bending coefficient calculation chart of parallelogram plate that exposes to uniform load in a variety of support conditions for designers .

This paper examines the bearing capacity and stability of a catenary axis uniform cross-section multi-span stone arch bridge with solid spandrels after strengthening and widening, in the light of the Code for Design of Highway Masonry Bridges and Culverts (JTG D61-2005) published by the Ministry of Communications of the People's Republic of China. Taking the West Ulanhot Large Bridge built in cold area of Inner Mongolia in 1960s as an example, the effect of dead load, live load and temperature variation after and before strengthening as well as multi-arch action were considered. Through calculating the bearing capacity and stability of stone multiple arch bridge, compared with the results of loading test and follow-up survey on operation condition for many years, the safety and effectiveness of strengthening scheme are evaluated.

The inclusion complex of dibenzoylmathane(DBM)with β-cyclodextrin(β-CD)was studied. UV-spectrophotometer was used to investigate the complexation behaviour in liquid medium, and to demonstrate that the DBM aqueous solubility increased 7.27times due to complexation with β-CD and the inclusion rate of DBM was high to 95.92 percent and the drug-loading constant is also high to 37.86ug/g. Solid samples prepared by solution-agitating method. FT-IR was employed to assess the formation of the inclusion complex. Dissolution analysis indicated that dissolution properties of DBM/β-CD complex were superior compared to both pure DBM and the corresponding physical mixture of DBM and β-CD.