We develop a new method for smooth and continuous space-variant alignment of the liquid crystal medium in micro-patterned structures, which is based on a radial micro-structured pattern of polymeric ribbons exhibiting...We develop a new method for smooth and continuous space-variant alignment of the liquid crystal medium in micro-patterned structures, which is based on a radial micro-structured pattern of polymeric ribbons exhibiting out-of-plane orientation with respect to the ITO-coated glass plates. Thanks to the broad range of electrical tunability of the optical retardation for the micro-patterned liquid crystal structures, transformation of the fundamental Gaussian beam into different types of specific beams, including generalized cylindrical vector beams, vortex beams, and vectorial vortex beams, is efficiently demonstrated.展开更多
Application of flame retardants is limited because of environmental requirements. This work introduces conventional magnetic nanoparticles as a new class of nontoxic and effective flame retardant. Fe3O4 enhanced both ...Application of flame retardants is limited because of environmental requirements. This work introduces conventional magnetic nanoparticles as a new class of nontoxic and effective flame retardant. Fe3O4 enhanced both the thermal stability and flame retardant properties of a poly（vinyl alcohol） matrix. Nanoparticles were synthesized via a simple precipitation reaction without using an inert atmosphere at room temperature. The effects of different precursors and acrylamide on the morphology of the products were investigated. Nanoparticles exhibited a ferrimagnetic behavior at room temperature. To prepare the magnetic nanocomposite, Fe3O4 nanoparticles were added to the poly（vinyl alcohol）. In the presence of a flame, the magnetic nanoparticles remained together, showed resistance to dripping and protected the polymer matrix. Dispersed nanoparticles play a role of a magnetic barrier layer, which slows product volatilization and prevents flames and oxygen from reaching the sample during decomposition of the polymer.展开更多
基金supported by the National Natural Science Foundation of China(No.11674182)the National Basic Research Program of China(No.2013CB328702)+5 种基金the Tianjin Natural Science Foundation(No.17JCYBJC16700)the 111 Project(No.B07013)the PCSIRT(No.IRT_13R29)the National Research Program of Slovenia(No.P1-0192)the Hundred Young Academic Leaders Program of Nankai Universitythe Collaborative Innovation Center of Extreme Optics,Shanxi University
文摘We develop a new method for smooth and continuous space-variant alignment of the liquid crystal medium in micro-patterned structures, which is based on a radial micro-structured pattern of polymeric ribbons exhibiting out-of-plane orientation with respect to the ITO-coated glass plates. Thanks to the broad range of electrical tunability of the optical retardation for the micro-patterned liquid crystal structures, transformation of the fundamental Gaussian beam into different types of specific beams, including generalized cylindrical vector beams, vortex beams, and vectorial vortex beams, is efficiently demonstrated.
文摘Application of flame retardants is limited because of environmental requirements. This work introduces conventional magnetic nanoparticles as a new class of nontoxic and effective flame retardant. Fe3O4 enhanced both the thermal stability and flame retardant properties of a poly（vinyl alcohol） matrix. Nanoparticles were synthesized via a simple precipitation reaction without using an inert atmosphere at room temperature. The effects of different precursors and acrylamide on the morphology of the products were investigated. Nanoparticles exhibited a ferrimagnetic behavior at room temperature. To prepare the magnetic nanocomposite, Fe3O4 nanoparticles were added to the poly（vinyl alcohol）. In the presence of a flame, the magnetic nanoparticles remained together, showed resistance to dripping and protected the polymer matrix. Dispersed nanoparticles play a role of a magnetic barrier layer, which slows product volatilization and prevents flames and oxygen from reaching the sample during decomposition of the polymer.
