Introduction: Solar radiation has a major role in design, utilization, development, and planning of solar energy. The most important source of natural ultraviolet radiation is the sun, which has an important role in many biologic processes. Some of these processes are useful, like the production of vitamin D in the body, or curing rickets, and some of them are not, such as ski...

cupric oxide nanostructures were synthesized via a simple reaction between copper nitrate and sodium hydroxide using a sonochemical-assisted method. the synthesized cuo was then characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier transform infrared, ultraviolet-visible and photoluminescence spectroscopy. our studies show that the cuo na...

Photon frequency conversion using optical materials is a common strategy for light generation and utilization. Materials capable of visible-to-ultraviolet (UV) have attracted particular attention due to their potential applications in nonlinear optics, biophotonics, as well environmental sciences. There are four main mechanisms visible-to-UV processes, including second-harmonic generation, two-...

The ichthyotoxin of Prymnesium parvum is inactivated by visible (400 to 510 mmu) as well as by ultraviolet light (255 mmu). The changes in the absorption spectrum of purified (pigment-free) ichthyotoxin during this process indicate that different mechanisms may be involved in the inactivation by visible or ultraviolet light. Photoinactivation is not affected by the presence of cells, cell pigme...