RESUMO
In this study, we report on the development and testing of hydrophobic coatings using cellulose fibers. The developed hydrophobic coating agent secured hydrophobic performance over 120°. In addition, a pencil hardness test, rapid chloride ion penetration test, and carbonation test were conducted, and it was confirmed that concrete durability could be improved. We believe that this study will promote the research and development of hydrophobic coatings in the future.
RESUMO
In this paper, we report a theoretical study on the electronic-optical properties of the organic light emitting diodes (OLEDs) devices having a multilayer structure which consists of N,N'- bis(3-methylphenyl)-N,N'-bis(phenyl)benzidine (TPD) as a hole transport layer (HTL) and tris(8-hydroxyquinolinato)aluminum (Alq3) as an electron transport layer (ETL). We investigated the angular dependence of the light density of emission as well as CIE chromaticity for devices with and without a distributed Bragg reflector (DBR) between the ITO and the glass wherein the DBR comprise two species of materials with different refractive indices. Our simulation revealed that the insertion of the bottom mirror plays a critical role for the improvement of in the emission efficiency of 17% and the sharper emission characteristics. We found out that the chromaticity as well as the viewing angle improved with the presence of the bottom mirror.
RESUMO
In this paper, we report our numerical study on the electronic-optical properties of the organic light emitting diodes (OLEDs) devices. In order to calculate the electrical and optical characteristics such as the transport behavior of carriers, recombination kinetics, and emission property, we undertake the finite element method (FEM) in OLEDs. Our model includes Poisson's equation, continuity equation to account for behavior of electrons and holes and the exciton continuity/transfer equation to account for generation and decay of the exciton. We employ the multilayer structure that consists of Poly(3,4)-ethylendioxy thiophene-polystyrenesulfonate ( PEDOT: PSS); Bis[(1-naphthyl)-N-phenyl]benzidine (α-NPD); 4,4'-N,N'-dicarbazole-biphenyl (CBP) doped with Ir(ppy)3; a 2-(4-Biphenylyl)-5-(4-tert-butylphenyl-1,3,4-oxadiazole) (Bu-PBD). We demonstrate that the refractive indexes of each material affect the emission property and barrier height of the interface influences the behavior of charges and the generation of exciton.
