Polymerizations with multiple mechanisms performed simultaneously are promising but very challenging. As the key limitation,the complicated mutual influence between different mechanisms can be hardly defined and measu...Polymerizations with multiple mechanisms performed simultaneously are promising but very challenging. As the key limitation,the complicated mutual influence between different mechanisms can be hardly defined and measured. Herein we establish a universal framework for the assessment of mutual influence between different mechanisms using binary polymerization for demonstration. The kinetics and thermodynamics of polymerization with two mechanisms are compared with the corresponding homopolymerization and the difference is expressed by a hybrid function. The hybrid function is composed of a hybrid parameter that describes the extent of mutual influence and a function that describes necessary conditions for mutual influence to occur. The extent of mutual influence can be calculated using kinetic and thermodynamic data without details of reaction mechanisms, for the first time providing a straightforward method to assess the mutual influence between different polymerization mechanisms.We envision that the method has potential in more complex systems with multiple mechanisms/monomers with mutual influence.展开更多
The high degree of freedom of multimechanism metasurfaces has greatly facilitated multifunction or even multiphysics design for practical applications.In this work,to achieve camouflages simultaneously in microwave,in...The high degree of freedom of multimechanism metasurfaces has greatly facilitated multifunction or even multiphysics design for practical applications.In this work,to achieve camouflages simultaneously in microwave,infrared,and optical regimes,we propose a multimechanism-empowered metasurface composed of four elemental indium-tin-oxide-based meta-atoms.Each meta-atom can modulate microwaves both in phase and magnitude through polarization conversion and resonance absorption,which can realize radar stealth at 8–14 GHz.The reflective amplitude is less than−10 dB.When the incident angle increases to 60°,the reflective amplitude is still less than−3 dB.The far-field scattering patterns of microwaves are modulated by destructive interferences of reflected waves,which results in diffusion-like scattering due to randomly distributed reflection phases on the metasurface.The superposition of microwave absorption and diffuse reflection enables broadband microwave scattering reduction of the metasurface.Meanwhile,the emissivity of four types of meta-atoms covers from 0.3–0.8 at 3–14μm due to delicately designed occupation ratios.The infrared radiation of the metasurface exhibits the characteristics of digital camouflage in infrared imaging.To demonstrate this method,prototypes were fabricated and measured.The measured results are consistent with the simulated ones.The angular stability in the microwave range within 0°–60°was also demonstrated.This work presents an approach to achieving multispectrum functions with integrated multimechanisms in a single functional metasurface layer and offers a new methodology for custom-designing infrared performance.Moreover,the simplicity of the structure offers significant cost control and large-scale fabrication advantages.展开更多
基金supported by the National Natural Science Foundation of China (51690151, 22001166)。
文摘Polymerizations with multiple mechanisms performed simultaneously are promising but very challenging. As the key limitation,the complicated mutual influence between different mechanisms can be hardly defined and measured. Herein we establish a universal framework for the assessment of mutual influence between different mechanisms using binary polymerization for demonstration. The kinetics and thermodynamics of polymerization with two mechanisms are compared with the corresponding homopolymerization and the difference is expressed by a hybrid function. The hybrid function is composed of a hybrid parameter that describes the extent of mutual influence and a function that describes necessary conditions for mutual influence to occur. The extent of mutual influence can be calculated using kinetic and thermodynamic data without details of reaction mechanisms, for the first time providing a straightforward method to assess the mutual influence between different polymerization mechanisms.We envision that the method has potential in more complex systems with multiple mechanisms/monomers with mutual influence.
基金National Key Research and Development Program of China(2022YFB3806200)National Natural Science Foundation of China(62201609,62401614)+1 种基金Natural Science Basic Research Program of Shaanxi Province(2024JC-YBMS-504)Shaanxi Key Science and Technology Innovation Team Project(2023-CX-TD-48)。
文摘The high degree of freedom of multimechanism metasurfaces has greatly facilitated multifunction or even multiphysics design for practical applications.In this work,to achieve camouflages simultaneously in microwave,infrared,and optical regimes,we propose a multimechanism-empowered metasurface composed of four elemental indium-tin-oxide-based meta-atoms.Each meta-atom can modulate microwaves both in phase and magnitude through polarization conversion and resonance absorption,which can realize radar stealth at 8–14 GHz.The reflective amplitude is less than−10 dB.When the incident angle increases to 60°,the reflective amplitude is still less than−3 dB.The far-field scattering patterns of microwaves are modulated by destructive interferences of reflected waves,which results in diffusion-like scattering due to randomly distributed reflection phases on the metasurface.The superposition of microwave absorption and diffuse reflection enables broadband microwave scattering reduction of the metasurface.Meanwhile,the emissivity of four types of meta-atoms covers from 0.3–0.8 at 3–14μm due to delicately designed occupation ratios.The infrared radiation of the metasurface exhibits the characteristics of digital camouflage in infrared imaging.To demonstrate this method,prototypes were fabricated and measured.The measured results are consistent with the simulated ones.The angular stability in the microwave range within 0°–60°was also demonstrated.This work presents an approach to achieving multispectrum functions with integrated multimechanisms in a single functional metasurface layer and offers a new methodology for custom-designing infrared performance.Moreover,the simplicity of the structure offers significant cost control and large-scale fabrication advantages.
