Electrostatic interactions between an ESIPT molecule 2-(5'-amino-2'-hydroxyphenyl)benzothiazole (AHBT) and a phenylborate derivative give blue-green emission in acetic acid solution, but interestingly, vigorous (or mechanical) shaking of the solution leads to the formation of organic AHBT nanoparticles, which results in fluorescence colour switching from blue-green to yellow-orange.

— The luminescence of MgO single crystals has been investigated using a scanning electron microscope (SEM) with a detection system for spectroscopic cathodoluminescence (CL) studies. The corrected CL spectrum of MgO consists of a large blue band with a maximum at 460 nm and a broad red emission with a dominant 722 nm peak. Annealing treatments in air, carbon monoxide or hydrogen change the spec...

Exploiting a controllable technique for red and blue shifting of quantum well’s bandgap energy, we have fabricated LED sources accessing a wide frequency spectrum along with all-optical intensity modulator devices. . We demonstrate bandgap tuning of InGaAsP multiple quantum well structures by utilizing an impurity free vacancy diffusion technique. Substantial modification of the bandgap energy ...

The photo- and electroluminescent properties of single-layer two-component blends composed of one blue emitter polymer and one green emitter polymer were studied. The blue emitter, poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(9,9-di-{5'-pentanyl}-fluorenyl-2,7-diyl)] (PFOFPen), was used as the matrix, and the green emitter, poly[(9,9-dihexylfluorenyl-2,7-diyl)-alt-co-(bithiophene)] (F6T2), was ...

A new scorpionate borate ligand K[HB(7-azain)3](1, 7-azain = 7-azaindolyl) has been obtained from the reaction of KBH4 with excess 7-azaindole. The scorpionate ligand 1 was found to be able to form complexes with Zn(II) and Cu(I) ions. Complex 2 with the formula [BH(7-azain)3](ZnCl) has been obtained from the reaction of ZnCl2 with 1. Complex 3 with the formula [BH(7-azain)3][Cu(PPh3)] has been...

We report the discovery of a population of nearby, blue early-type galaxies with high star formation rates (0.5 < SFR < 50 M⊙yr). They are identified by their visual morphology as provided by Galaxy Zoo for SDSS DR6 and their u − r colour. We select a volume-limited sample in the redshift range 0.02 < z < 0.05, corresponding to luminosities of approximately L and above, and with u − r colours s...

The spectroscopic behavior of gadolinium gallium garnet (Gd3Ga5O12, GGG) nanocrystals codoped with 1% each of Tm3+ and Yb3+ prepared via a solution combustion synthesis procedure was investigated. Initial excitation of the codoped nanocrystals with 465.8 nm (into the 1G4 state) showed a dominant blue-green emission ascribed to the 1G4-3H6 transition as well as red and NIR emissions from the 1G4...

We carried out degradation analysis of a blue phosphorescent organic light emitting diode by both impedance spectroscopy and transient electroluminescence (EL) spectroscopy. The number of semicircles observed in the Cole-Cole plot of the modulus became three to two after the device was operated for 567 hours. Considering the effective layer thickness of the initial and degraded devices did not ...

A tetradentate Pd(ii) complex, Pd3O3, which exhibits highly efficient excimer emission is synthesized and characterized. Pd3O3 can achieve blue emission despite using phenyl-pyridine emissive ligands which have been a mainstay of stable green and red phosphorescent emitter designs, making Pd3O3 a good candidate for stable blue or white OLEDs. Pd3O3 exhibits strong and efficient phosphorescent e...

The observations of solar flare onsets show rapid increase of hard and soft X-rays, ultra-violet emission with large Doppler blue shifts associated with plasma upflows, and Hα hydrogen emission with red shifts up to 1-4 Å. Modern radiative hydrodynamic models account well for blue-shifted emission, but struggle to reproduce closely the red-shifted Hα lines. Here we present a joint hydrodynamic ...