This study investigated the correlation between the antibacterial ability of silver nanoparticle air filters with the related dust loading. In addition, a decay equation with which the life cycle of the antibacterial air filters could be predicted was developed. Samples of a HEPA (High Efficiency Particulate Air) filter were coated with an antibacterial agent, silver nanoparticles, which were synthesized via an atmospheric spark discharge method and deposited onto the filters using forced convection flow. A specific amount of dust particles was then blown onto each filter sample. Two kinds of bacteria, Escherichia coli (E. coli), representing Gram-negative bacteria, and Staphylococcus epidermidis (S. epidermidis), representing Gram-positive bacteria, were used in order to examine the antibacterial abilities of the filter samples. The results of the disc diffusion method showed that the dust loading adversely affected the antibacterial efficacy. However, the silver nanoparticle mass density on a filter with a certain amount of dust does increase the antibacterial ability to a certain extent. Finally, decay equations for the decline rates of the antibacterial ability against E. coli and S. epidermidis were obtained with a dimensionless pressure drop across the antibacterial filter samples.

A novel methylphenyl silicone resin, with M, D, and T units, was synthesized by cohydrolysis and cocondensation method from dimethyldimethoxysilane (Me 2 Si(OMe) 2 ), phenyltrimethoxysilane (PhSi(OMe) 3 ), hexamethyldisiloxane, and 1,3-divinyl-1,1,3,3tetramethyldisiloxane in toluene/water mixture catalyzed by hydrochloric acid and trifluoromethanesulfonic acid. The vinyl endcapped MDT silicone resins were chosen for reinforcement filler to enhance the mechanical properties of silicone-based ablative composites. The effects of resins with various R/Si ratios, vinyl content, and loadings on mechanical properties of PMPS rubbers were investigated. It was revealed that on the premise of good fluidity and processing performance, MDT resin showed excellent reinforcing effect and thermal stability compared with silica. MDT reinforced ablative composite showed satisfactory mechanical and antiablative properties. The linear ablation rate was 0.01 mm/s, which maybe associated with high yield of charred residue in thermogravimetric analysis results.

K 3 B 6 O 10 Cl is a perovskite-like nonlinear optical (NLO) crystal, which exhibits large second harmonic generation (SHG) response. Based on density-functional theory, we investigate the influence of pressure on SHG tensor of K 3 B 6 O 10 Cl. At zero pressure, the non-centrosymmetric distortion of K 3 B 6 O 10 Cl from BO 4 tetrahedron results in the similar SHG tensor to b-BaB 2 O 4 (BBO). At 50 GPa, the ClK 6 octahedron distortion of K 3 B 6 O 10 Cl becomes the main source of SHG and give similar SHG tensor to LiNbO 3 . Therefore, pressure induces K 3 B 6 O 10 Cl from a BBO-like NLO material to a LiNbO 3 -like NLO material. V C 2013 AIP Publishing LLC. [http://dx.

In this study, we fabricated air filters coated with Ag nanoparticles and evaluated their antibacterial efficiencies using colony counting method (CCM) and disc diffusion method (DDM) as a function of Ag nanoparticle content. Two kinds of bacterium Escherichia coli (Gram-negative bacterium), and Staphylococcus epidermidis (Gram-positive bacterium) were tested. As the amount of antibacterial agent increased, the inhibition zone width (IZW), which is the result of DDM, gradually increased and reached the maximum value, while the number of colony forming unit (CFU), which is the result of CCM, decreased and became zero. We derived a correlation equation using the CCM and DDM results, which was used to define the quantitative antibacterial efficiency of the filters according to DDM results.

Performing ab-initio total-energy calculations to investigate the adsorption and diffusion processes of the Au atoms with both the clean Si(001)-(1×1) and H-terminated Si(001)-(2×1) surfaces. It was found that, on the clean Si(001)-(1×1) surface, the most stable adsorption sites for Au atoms are middle part of four Si atoms, while on H-terminated Si(001)-(2×1) surface, the most stable sites are the middle part of a Si-Si dimer. The result showed that surface hydrogenation make most stable site transfer and affect the adsorption of Au on Si(001) surface.