Poly(methyl silsesquioxane) (MSQ)-titania optical thin films were synthesized and characterized in this study. An MSQ precursor with a mixed cage and network structure was prepared first, which had end groups of Si-OH and Si-OCH 3 . Then, it was reacted with titanium(IV) n-butoxide, followed by spin-coating and multi-step curing to form the optical thin films. The FTIR spectra suggest successful bonding of MSQ and titania. The prepared films were very uniform with an amorphous nanoscale titania segment from the results of FE-SEM, AFM, and XRD. Excellent thermal stability was found for the prepared MSQ-titania materials. The optical properties of the prepared MSQ-titania films could be tuned by the titania content. By increasing the titania content from 10.6 to 41.6 wt.%, the absorption edge and refractive index were increased from 291 to 310 nm, and from 1.394 to 1.561, respectively. These results are attributed to the growing size effect of the titania segment. Optical planar waveguides were fabricated from the synthesized MSQ-titania films on top of a thermal oxide using a silicon wafer as the substrate. The optical loss of the studied planar waveguide decreased from 0.31 to 0.18 dB cm 21 with increasing titania content. This resulted from a reduction of the C-H bonding density due to the increasing titania composition.

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This paper proposes a new reinforcement structure called soil nets firstly, which is capable of strengthening foundations, slopes, and other structures with better effect than that of soilbags. This proposed geotextile structure typically contains several layers of soil net, which are placed in a unique way. One layer of soil net can be described as a collection of spherical soilbags that are connected together in two directions, one in which they are connected by ropes and another in which they are connected by the PP woven bags that contain the soil. A mechanical property analysis of the soil nets shows that the yield stress of the soil within the soil nets is improved, the tensile capacity of the soil nets is greater than that of the soil with which it is filled, and the equivalent coefficient of interlayer friction between the connected soil nets is larger than that for soilbags. Applications of this new reinforcement structure in the reinforcement of a foundation and a slope are considered, and the corresponding reinforcement effects are calculated. The calculation results demonstrate that the soil nets concept yields efficient reinforcement structures with many advantages.