Luminescence from crystals is often anisotropic and it leads to the polarization behavior of luminescence from single crystalline particles, as exemplified here with the upconversion luminescence from a single NaYF4 nanodisk. Nanodisk aggregates exhibit polarization dependent luminescence with different polarization degrees, which depends on the orientation and distribution of nanoparticles.

Although the application of biodegradative genetically engineered micro organisms (GEMs) for bioremediation is very promising, the risks of their release should be assessed before their introduction into the environment. Lux-marked Ralstonia eutropha H850Lr (formerly Alcaligenes eutrophus H850Lr) was introduced into sterile and non-sterile soil microcosms at matric potentials ?2.11, ?30, ?750, ...

objective(s): this paper describes synthesispolyvinyl alcohol/caf2:er nanofibers because of  its  photoluminescence properties.materials and methods:  first, caf2:er nanocomposite synthesized with co-precipitation method. in order to prepare polyvinyl alcohol (pva)/caf2:er nanofibers, caf2:er nanocomposites were added to the polyvinyl alcohol (pva) polymer. pva/caf2:er composite nanofibers were...

Popp and Yan [F. A. Popp, Y. Yan, Phys. Lett. A 293 (2002) 93] proposed a model for delayed luminescence based on a single time-dependent coherent state. We show that the general solution of their model corresponds to a luminescence that is a linear function of time. Therefore, their model is not compatible with experimental delayed luminescence. Moreover, the functions that they use to describ...

Cone beam X-ray luminescence tomography can realize fast X-ray luminescence tomography imaging with relatively low scanning time compared with narrow beam X-ray luminescence tomography. However, cone beam X-ray luminescence tomography suffers from an ill-posed reconstruction problem. First, the feasibility of experiments with different penetration and multispectra in small animal has been teste...

Shockley-Read-Hall recombination kinetics has been applied to explain the luminescence mechanism of erbium luminescence in silicon. Erbium atoms in silicon have been considered as recombination centers with specific values of capture and emission coefficients. Electron-hole recombination through these levels has been considered to be the origin of erbium excitation. Equating the capture and emi...

Previous studies of the luminescence system of Siphamia versicolor (Perciformes: Apogonidae) identified a ventral light organ, reflector, lens, duct, and a ventral diffuser extending from the throat to the caudal peduncle. The control and function of luminescence in this and other species of Siphamia, however, have not been defined. Morphological examination of fresh and preserved specimens ide...

The luminescence of the marine dinoflagellate Gonyaulax polyedra shows an endogenous diurnal rhythm. The effect of light during the phase of low luminescence capacity may be observed as an enhancement of luminescence during the subsequent bright phase. During the bright phase, however, illumination diminishes the capacity for luminescence. The action spectra for these two effects of light have ...

Significant multiplexing capacity of optical time-domain coding has been recently demonstrated by tuning luminescence lifetimes of the upconversion nanoparticles called 'τ-Dots'. It provides a large dynamic range of lifetimes from microseconds to milliseconds, which allows creating large libraries of nanotags/microcarriers. However, a robust approach is required to rapidly and accurately measur...