The radiative cooling of butterfly wing scales hierarchy has great value in understanding how poikilotherms adapt to the environment and developing bionic ma-terials.However,it remains unclear what the cooling system ...The radiative cooling of butterfly wing scales hierarchy has great value in understanding how poikilotherms adapt to the environment and developing bionic ma-terials.However,it remains unclear what the cooling system is like and how the vari-ation of hierarchy affects the cooling efficiency.Therefore,the correlation between the variations of the structure and emissivity of scale hierarchy is thoroughly investigated in Tirumala limniace(Cramer,1775),whose thermal properties are highly heteroge-neous among different wings and regions but similar between males and females.Pat-terns were deduced from the biological and model simulation experiments.The scale hierarchy varies at the micro-to nanolevel on both surface and section,correspond-ing to the variating emissivity.Scales on wing veins and margins have large nanostruc-tured units with small lumens and are distinctly thickened,which bring extraordinarily high emissivity.The variations of light and dark scales,respectively,lead to the high emissivity of the middle region of wings and the front wings.Generally,the elevation of the inner surface area and the thickness of the chitin is the key to enhancing the cooling efficiency.For the first time,the effects of the variation of hierarchy toward emissivity of the mid-infrared spectrum are systematically clarified.It is demonstrated that wing scales integrally differentiate in coping with the heterogeneous cooling needs,which may benefit in balancing multifunctions and the development toward the adap-tation to the abiotic environment.The study provides insights into the comprehensive thermoregulation system of butterflies and the further development of radiative cooling materials.展开更多
基金supported by the National Natural Science Foundation of China[No.31702072]the Natural Science Foundation of Jiangsu Province[BK20210159]+1 种基金the Jiangsu Agricultural Science and Technology Innovation Fund[CX(20)3184]the Open Foundation of Key LaboratoryofUrban Agriculture,Ministryof Agriculture and Rural Areas[UA201906].
文摘The radiative cooling of butterfly wing scales hierarchy has great value in understanding how poikilotherms adapt to the environment and developing bionic ma-terials.However,it remains unclear what the cooling system is like and how the vari-ation of hierarchy affects the cooling efficiency.Therefore,the correlation between the variations of the structure and emissivity of scale hierarchy is thoroughly investigated in Tirumala limniace(Cramer,1775),whose thermal properties are highly heteroge-neous among different wings and regions but similar between males and females.Pat-terns were deduced from the biological and model simulation experiments.The scale hierarchy varies at the micro-to nanolevel on both surface and section,correspond-ing to the variating emissivity.Scales on wing veins and margins have large nanostruc-tured units with small lumens and are distinctly thickened,which bring extraordinarily high emissivity.The variations of light and dark scales,respectively,lead to the high emissivity of the middle region of wings and the front wings.Generally,the elevation of the inner surface area and the thickness of the chitin is the key to enhancing the cooling efficiency.For the first time,the effects of the variation of hierarchy toward emissivity of the mid-infrared spectrum are systematically clarified.It is demonstrated that wing scales integrally differentiate in coping with the heterogeneous cooling needs,which may benefit in balancing multifunctions and the development toward the adap-tation to the abiotic environment.The study provides insights into the comprehensive thermoregulation system of butterflies and the further development of radiative cooling materials.
