In this present study reports the green synthesis of zinc oxide nanoparticles using Betel leaf extracts and zinc acetate. The functionalization of ZnO particles through Betel leaf extract mediated bio reduction of ZnO was investigated through X-ray diffraction, Field emission scanning electron microscopy, photoluminescence, thermal gravimetric-differential thermal analysis, hexagonal shaped ZnO...

We present Arecibo 21 cm spectroscopy, Keck HIRES Hβ spectroscopy, and WIYN R-band imaging of 11 nearby blue compact galaxies with effective B-band surface brightness SBe =19.4-21.2 mag arcsec−2 and effective radii Reff =0.6-1.9 kpc. This sample was selected to test the reliablility of mass estimates derived using optical emission linewidths, particularly for the blue compact star-forming galax...

Polarization-resolved electroluminescence studies of III-nitride blue and ultraviolet sUVd light-emitting diodes sLEDsd were performed. The LEDs were fabricated on nitride materials grown by metalorganic chemical vapor deposition on sapphire substrates s0001d. Transverse electric sTEd polarization dominates in the InGaN/GaN quantum-well sQWd blue LEDs sl8=458 nmd, whereas transverse magnetic sT...

A series of strict emission control measures were implemented in Beijing and surrounding regions to ensure good air quality during the 2014 Asia-Pacific Economic Cooperation (APEC) summit and 2015 Grand Military Parade (Parade), which led to blue sky days during these two events commonly referred to as "APEC Blue" and "Parade Blue". Here we calculated Multi-Axis Differential Optical Absorption ...

Nanoscale phosphorene quantum dots (PQDs) with few-layer structures were fabricated by pulsed laser ablation of a bulk black phosphorus target in diethyl ether. An intense and stable photoluminescence (PL) emission of the PQDs in the blue-violet wavelength region is clearly observed for the first time, which is attributed to electronic transitions from the lowest unoccupied molecular orbital (L...

Dielectric crystals doped with Ce3+ , Eu2 +, Sm2 +, and Yb2 + display broadband 5d-to-4f emission, and are candidate solid-state tunable laser materials. The absorption and emission wavelengths, however, are very host-sensitive, and a better understanding of 5d crystal field interactions is needed in order to design high performance materials. The adequacy of a purely ionic model of the crystal...

A new method by using a pulsed-laser Raman scattering technique was employed to estimate junction temperature of a fluorescence-resin-less blue-LED package. Temperature dependent Raman shift of E2 H mode of GaN layer in the blue-LED were obtained and were in good agreement with the experimental data published by the other researchers. This technique was applied to estimation of a junction tempe...

We have found for the first time a Balmer edge feature in the Big Blue Bump emission of a quasar. The feature is seen in the polarized flux spectrum of the quasar, where all the emissions from outside the nucleus are scraped off and removed. The existence of the Balmer-edge absorption feature directly indicates that the Big Blue Bump is indeed thermal and optically-thick.

A novel ambipolar spiro-configured D-A blue-light emitter bearing hole-transporting diphenylamino groups and electron-transporting phenylbenzimidazole groups was synthesized, characterized, and incorporated into an efficient single-layer organic light-emitting diode (OLED) device exhibiting blue-emission Commission International d'Eclairage (CIE) coordinates of 0.15 and 0.14, a turn-on potentia...

HST UV observations of V795 Her reveal a strong 2.6-h orbital variation in the prominent UV lines, in contrast to earlier (IUE) evidence of a 4.8-h period. Only the Civ line contains a strong blue-shifted, wind formed absorption component. Several lines exhibit a 'narrow' absorption feature near rest velocity which may originate in the disk, and a blue-shifted emission feature which accounts fo...