The synthetic fuzzy assessing method is usually applied to sensory evaluation. The method has simple and reliable virtue, and it is consistent with objective evaluation results. Using this method, system status of pla...The synthetic fuzzy assessing method is usually applied to sensory evaluation. The method has simple and reliable virtue, and it is consistent with objective evaluation results. Using this method, system status of plating solution evaporator is evaluated, and the result is applied to compensate a fuzzy controller. Experimental results have shown the correctness and the validity of the proposed approach.展开更多
Planar π-conjugated groups are of great interest to researchers in the exploration of optical materials with large birefringence.The key point is to control the orientation and spatial density of birefringence-active...Planar π-conjugated groups are of great interest to researchers in the exploration of optical materials with large birefringence.The key point is to control the orientation and spatial density of birefringence-active groups.Here,two metal-free UV birefringent crystals,β-(C_(3)H_(7)N_(6))_(2)Cl_(2)·H_(2)O and(C_(3)H_(7)N_(6))F·H_(2)O,were synthesized using an aqueous solution evaporation technique.They feature a two-dimensional layered structure composed of π-conjugated planar[C_(3)H_(7)N_(6)]+units with the same orientation.As a result,the title compounds exhibit a large birefringence(0.33-0.38@550 nm),not only exceeding that of most of the melamine-based materials but also being larger than that of the commercial birefringent materials.Moreover,UV-Vis-NIR diffuse reflectance spectra and thermal stability analysis demonstrate that(C_(3)H_(7)N_(6))F·H_(2)O exhibits a shorter UV absorption edge and higher thermal stability because of the more electronegative F element.The first-principles calculations elucidate the origin of their optical properties.The effect of group packing density and orientation on the birefringence in melamine-based compounds has been discussed in detail for the first time.The arrangement of groups regulated by halogen atoms will inspire the exploration of new birefringent materials with large optical anisotropy.展开更多
A new crystal,C_(10)H_(10)ClNO_(3),was prepared by the solution evaporation technique.It shows a large birefringence of 0.345@550 nm and high thermal stability.Structural analysis and theoretical calculations demonstr...A new crystal,C_(10)H_(10)ClNO_(3),was prepared by the solution evaporation technique.It shows a large birefringence of 0.345@550 nm and high thermal stability.Structural analysis and theoretical calculations demonstrate that the isoquinoline carboxylic acid is responsible for optical anisotropy and can be used as an excellent birefringence-active gene.展开更多
文摘The synthetic fuzzy assessing method is usually applied to sensory evaluation. The method has simple and reliable virtue, and it is consistent with objective evaluation results. Using this method, system status of plating solution evaporator is evaluated, and the result is applied to compensate a fuzzy controller. Experimental results have shown the correctness and the validity of the proposed approach.
基金supported by the Natural Science Foundation of Fujian Province(2019J01762)the Doctoral Research Start-up Fund of Minjiang University(MJY19014).
文摘Planar π-conjugated groups are of great interest to researchers in the exploration of optical materials with large birefringence.The key point is to control the orientation and spatial density of birefringence-active groups.Here,two metal-free UV birefringent crystals,β-(C_(3)H_(7)N_(6))_(2)Cl_(2)·H_(2)O and(C_(3)H_(7)N_(6))F·H_(2)O,were synthesized using an aqueous solution evaporation technique.They feature a two-dimensional layered structure composed of π-conjugated planar[C_(3)H_(7)N_(6)]+units with the same orientation.As a result,the title compounds exhibit a large birefringence(0.33-0.38@550 nm),not only exceeding that of most of the melamine-based materials but also being larger than that of the commercial birefringent materials.Moreover,UV-Vis-NIR diffuse reflectance spectra and thermal stability analysis demonstrate that(C_(3)H_(7)N_(6))F·H_(2)O exhibits a shorter UV absorption edge and higher thermal stability because of the more electronegative F element.The first-principles calculations elucidate the origin of their optical properties.The effect of group packing density and orientation on the birefringence in melamine-based compounds has been discussed in detail for the first time.The arrangement of groups regulated by halogen atoms will inspire the exploration of new birefringent materials with large optical anisotropy.
基金supported by the National College Students Innovation and Entrepreneurship Training Program(202210395010)the Natural Science Foundation of Fujian Province(2019J01762)the Doctoral Research Start-up Fund of Minjiang University(MJY19014).
文摘A new crystal,C_(10)H_(10)ClNO_(3),was prepared by the solution evaporation technique.It shows a large birefringence of 0.345@550 nm and high thermal stability.Structural analysis and theoretical calculations demonstrate that the isoquinoline carboxylic acid is responsible for optical anisotropy and can be used as an excellent birefringence-active gene.
