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排序方式: 共有437条查询结果,搜索用时 15 毫秒
431.
Bouit PA Escande A Szűcs R Szieberth D Lescop C Nyulászi L Hissler M Réau R 《Journal of the American Chemical Society》2012,134(15):6524-6527
A synthetic route to planar P-modified polycylic aromatic hydrocarbons (PAHs) is described. The presence of a reactive σ(3),λ(3)-P moiety within the sp(2)-carbon scaffold allows the preparation of a new family of PAHs displaying tunable optical and redox properties. Their frontier molecular orbitals (MOs) are derived from the corresponding phosphole MOs and show extended conjugation with the entire π framework. The coordination ability of the P center allows the coordination-driven assembly of two molecular PAHs onto a Au(I) ion. 相似文献
432.
The synthesis, characterization and singlet oxygen quantum yield of novel unsymmetrical dendrons containing photosensitizing units at their periphery is reported. Boc-protected 2,2′-(ethylenedioxy)-bis-ethylamine reacted with methyl acrylate and ethylene diamine to give half-dendrimers 4 and 5 with 2 and 4 end groups, respectively. Amine-tethered porphyrins and compounds 4 and 5 were efficiently coupled in DMF at 100 °C to give the functionalized dendrons. UV-visible and fluorescence emission spectra showed that the photophysical properties of the porphyrins were retained in the dendrimers. 相似文献
433.
Barsu C Fortrie R Nowika K Baldeck PL Vial JC Barsella A Fort A Hissler M Bretonnière Y Maury O Andraud C 《Chemical communications (Cambridge, England)》2006,(45):4744-4746
The design of new chromophores presenting simultaneous SHG and TPEF properties is reported. 相似文献
434.
Su HC Fadhel O Yang CJ Cho TY Fave C Hissler M Wu CC Réau R 《Journal of the American Chemical Society》2006,128(3):983-995
The photophysical, electrochemical, and optoelectronic properties of conjugated systems incorporating dibenzophosphole or phosphole moieties are described. Dibenzophosphole derivatives are not suitable materials for OLEDs due to their weak photoluminescence (PL) in the solid state and the instability of the devices. Variation of the substitution pattern of phospholes and chemical modification of their P atoms afford thermally stable derivatives, which are photo- and electroluminescent. Comparison of the optical properties of solution and thin film of thioxophospholes shows that these compounds do not form aggregates in the solid state. This property, which is also supported by an X-ray diffraction study of three novel derivatives, results in an enhancement of the fluorescence quantum yields in the solid state. In contrast, (phosphole)gold(I) complexes exhibit a broad emission in thin film, which is due to the formation of aggregates. Single- and multilayer OLEDs using these P derivatives as the emissive layer have been fabricated. The emission color of these devices and their performances vary with the nature of the P material. Interestingly, di(2-thienyl)thiooxophosphole is an efficient host for the red dopant DCJTB, and devices using the gold complexes have broad emission spectra. 相似文献
435.
Farouil Léa Duchaudé Yolène Zozo Léa Sylvestre Muriel Lafay Florent Marote Pedro Cebrián-Torrejón Gerardo 《Journal of Solid State Electrochemistry》2023,27(5):1249-1259
Journal of Solid State Electrochemistry - Today, pest control by chemical treatment is the main strategy against pest insects. This article proposes to show how cyclic voltammetry of immobilized... 相似文献
436.
437.
The properties of a composite material are gouverned by the fibre, the matrix and the interface properties. However, in a test, used to determine a composite property, the influence of the interface is often muffled by other influences (fibre volume fraction, inhomogeneity, voids, defects,). To understand the relation between the composite performance and the fibre-matrix interface properties, it is necessary to work in several steps. In a first step, a thorough understanding of the fibre-matrix interface behaviour is needed. This not only involves the determination of the interface properties using micromechanical test methods, but also the fundamental study of the stresses at the interface and of the failure events occuring during the test. In this paper, the fragmentation, the pull-out and the micro-indentation test will be elaborated. The former test is used to explain the importance of an accurate data reduction model. In a second step, the influence of these interface properties on the composite performance is investigated. It is well known that an improved interface quality is beneficial for the transverse tensile and the interlaminar shear strength. However, a strong fibre-matrix interface is not favourable for all composite properties. This is illustrated by an overview of micromechanical models, developed to understand the macromechanical behaviour of composites. Three properties are addressed: the longitudinal tensile strength, the interlaminar fracture toughness, and the damage development in cross-ply laminates. 相似文献