Phase retardation of both extraordinary and ordinary polarized rays passing through a liquid crystal (LC) cell with homogeneous and inhomogeneous LC director distribution is calculated as a function of the LC pretilt angle θ₀ on the cell substrates in the range 0 ≤ θ₀ ≤ 90°. The LC pretilt on both substrates can have the same or opposite direction, thereby forming homogeneous, splay, or bend director configurations. At the same pretilt angle value, the largest phase retardation ΔΦ is observed in splay LC cells, whereas the smallest phase retardation is observed in bend cells. For the θ₀ values close to 0, 45°, and 90°, analytical approximations are derived, showing that phase retardation depends on LC birefringence variation.

The present study a comprehensive analysis of the antibacterial properties of a composite material based on borosiloxane and zinc oxide nanoparticles (ZnO NPs). The effect of the polymer matrix and ZnO NPs on the generation of reactive oxygen species, hydroxyl radicals, and long-lived oxidized forms of biomolecules has been studied. All variants of the composites significantly inhibited the division of E. coli bacteria and caused them to detach from the substrate. It was revealed that the surfaces of a composite material based on borosiloxane and ZnO NPs do not inhibit the growth and division of mammalians cells. It is shown in the work that the positive effect of the incorporation of ZnO NPs into borosiloxane can reach 100% or more, provided that the viscoelastic properties of borosiloxane with nanoparticles are retained.

Optical and electro-optical methods of liquid crystal (LC) director pretilt angle measurement are described for LC cells with homogeneous and inhomogeneous LC director distribution. The LC pretilt on both LC substrates can have the same or opposite direction. The phase retardation difference of both extraordinary and ordinary polarized rays passing through an LC cell with homogeneous and inhomogeneous LC director distribution has been calculated versus the LC pretilt angle θ(0) on the cell's substrates in the range 0≤θ(0)≤90°. The experimental procedure for phase retardation difference determination by measurement of the LC cell transmission between crossed polarizers for cells with LC tilted alignment is described. The method developed can also be used in optical compensator design.

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New optical and electro-optical methods of LC director average tilt angle measurement are described in LC cells with homogeneous and inhomogeneous LC director distribution. The LC pretilt on both LC substrates can have the same or opposite direction. Both LC pretilt angle and polar anchoring energy values have been measured for both polar and weak polar liquid crystal materials on aligning films of organosilicon compounds (OC) of different molecular structure. The method developed can be used also in optical compensator design.