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The article gives a rigorous non-existence proof of free will in an indeterministic universe.

In this paper, mullite fiber reinforced mullite composites were prepared by stitched structural perform, the silica sol and alumina sol. In order to improve the compatibility of mullite fiber and silica sol matrix, interface coating was made by infiltration. The composites were prepared by the method of liquid phase infiltration, and the suitable ceramic heat treatment temperature was 750∼900°C though testing the damage of fiber strength after heat -treatment at different temperatures. Results showed that SiO2-Al2O3-ZrO2 interface coating could uniformly distribute on the surface of mullite fibers, and the appropriate interfacial bonding strength was obtained, which made a contribution to the high density mullite fiber reinforced mullite composite, whose density reached 1.75∼1.8g/cm3, tensile strength, bending strength and compressive strength reached 48.7MPa,65.4MPa and 82.7MPa, respectively. Dielectric constant was 3.2±0.1, Loss angle tangent was less than8×10-3.So mullite fiber reinforced mullite composites became a new generation of high temperature wave- transparent material.

The needle-punched woven silica fiber reinforced SiO2 ceramic matrix composites were prepared by liquid phase infiltration-in-situ solidification molding process. The prepared composites have high density and good uniformity, and the mechanical properties of the composites at room temperature. Microstructure, interfacial properties and dielectric properties at room temperature were investigated, and the strengthening and toughening mechanism of acupuncture-woven quartz fiber reinforced SiO2 ceramic matrix composites was discussed. The mechanical properties at room temperature show that the tensile strength, flexural strength, compressive strength and interlaminar shear strength of the composites reach 35.6MPa, 79.0MPa, 122.0MPa, 11.9MPa, respectively. Scanning electron microscopy (SEM) and energy spectrum of the fractures of the samples (EDS) observation and analysis showed that there was no interfacial reaction between the matrix and the fiber, and the interface was suitable. The main factors that improve the mechanical properties of composite materials at room temperature are crack steering, expansion barriers, and fiber pull-out. The dielectric properties of the composite at room temperature do not change or change much under different X, Ka, and Ku conditions. As the bulk density increases, the dielectric constant of the composite increases gradually, and the loss tangent is always maintained at 10-3 orders of magnitude.