The paper explores the possibilities of using carbonyl iron in the form of a powder for the manufacture of radar-absorbing paints-reducing the radar signature of the objects that they cover.The attenuation values in t...The paper explores the possibilities of using carbonyl iron in the form of a powder for the manufacture of radar-absorbing paints-reducing the radar signature of the objects that they cover.The attenuation values in the range of 4-18 GHz for various coating thicknesses,ranging from 0.5 to 2.00 mm with 0.5 mm increment,and for different absorber content-75%and 80%,as well as the use of two different binders in the form of epoxy resins with hardeners,were investigated.For the frequency of 18 GHz and a 1.5 mm thick coating with a 75%absorber content,Epidian 112 resin and Saduramid 10/50 hardener used as a binder,and the maximum attenuation level obtained equalled 20.2 d B at 16 GHz.Additionally,the absorber particle size ranging from 3 to 4μm and its higher mass content resulted in achieving the reflection loss above-12 d B in the entire 8-12.5 GHz range for layers between 1-and 1.5 mm thickness.The qualitative assessment of the tested samples in the context of camouflage in the radar range was also performed,using statistical analysis.展开更多
Thiophene and its derivatives have garnered substantial interest in the organic electronics sector,particularly in the development of polymer solar cells(PSCs).Herein,we present the synthesis of a new thiophene deriva...Thiophene and its derivatives have garnered substantial interest in the organic electronics sector,particularly in the development of polymer solar cells(PSCs).Herein,we present the synthesis of a new thiophene derivative,ClE-T,by a simple two-step method,comprising a monothiophene functionalized with a chlorine atom and an ester group.The ClE-T offers unique benefits resulting from the combination of the two groups.The incorporation of ClE-T into a polymer yields a polymer donor poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-chloro-4-(methoxycarbonyl)-2,5-thiophenediyl]](PBDT-ClET).ClE-T demonstrates synergistic effects that significantly downshift energy levels and enhance the crystallinity of PBDT-ClET.In conclusion,PBDT-ClET is incorporated as a third component in all-polymer solar cells(all-PSCs)to enhance charge transport,reduce energy loss,and achievemore favorable phase separation.Finally,the all-PSCs employing PBDT-ClET achieve a notable power conversion efficiency(PCE)of 19.04%,which is not only among the highest values in all-PSCs but also represents the record PCE achieved for eco-friendly all-PSCs.This work underscores the promising potential of the ClE-T unit as a building block for constructing easily synthesized polymers for high-performance PSCs.展开更多
文摘The paper explores the possibilities of using carbonyl iron in the form of a powder for the manufacture of radar-absorbing paints-reducing the radar signature of the objects that they cover.The attenuation values in the range of 4-18 GHz for various coating thicknesses,ranging from 0.5 to 2.00 mm with 0.5 mm increment,and for different absorber content-75%and 80%,as well as the use of two different binders in the form of epoxy resins with hardeners,were investigated.For the frequency of 18 GHz and a 1.5 mm thick coating with a 75%absorber content,Epidian 112 resin and Saduramid 10/50 hardener used as a binder,and the maximum attenuation level obtained equalled 20.2 d B at 16 GHz.Additionally,the absorber particle size ranging from 3 to 4μm and its higher mass content resulted in achieving the reflection loss above-12 d B in the entire 8-12.5 GHz range for layers between 1-and 1.5 mm thickness.The qualitative assessment of the tested samples in the context of camouflage in the radar range was also performed,using statistical analysis.
基金supported National Natural Science Foundation of China(grant nos.52422313,52173172,and 52173171)Open Research Fund of State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(grant no.PPCL2023-15)+7 种基金supported by University Students’Innovation Training Program(grant no.XJ202311078037)the Department of Education of Guangdong Province(grant no.2023KSY008)Research project of Guangzhou University(grant nos.RC2023030 and YJ2023052)the Department of Education of Guangdong Province(grant no.2023KSY008)Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(grant no.202255464)the Research&Development Projects in Key Areas of Guangdong Province,China(grant no.2019B010933001)supported by the Center for Computational Science and Engineering at the Southern University of Science and Technologysupport from the National Research Foundation of Korea(grant nos.2019R1A6A1A11044070 and 2020M3H4A3081814).
文摘Thiophene and its derivatives have garnered substantial interest in the organic electronics sector,particularly in the development of polymer solar cells(PSCs).Herein,we present the synthesis of a new thiophene derivative,ClE-T,by a simple two-step method,comprising a monothiophene functionalized with a chlorine atom and an ester group.The ClE-T offers unique benefits resulting from the combination of the two groups.The incorporation of ClE-T into a polymer yields a polymer donor poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-chloro-4-(methoxycarbonyl)-2,5-thiophenediyl]](PBDT-ClET).ClE-T demonstrates synergistic effects that significantly downshift energy levels and enhance the crystallinity of PBDT-ClET.In conclusion,PBDT-ClET is incorporated as a third component in all-polymer solar cells(all-PSCs)to enhance charge transport,reduce energy loss,and achievemore favorable phase separation.Finally,the all-PSCs employing PBDT-ClET achieve a notable power conversion efficiency(PCE)of 19.04%,which is not only among the highest values in all-PSCs but also represents the record PCE achieved for eco-friendly all-PSCs.This work underscores the promising potential of the ClE-T unit as a building block for constructing easily synthesized polymers for high-performance PSCs.
