background: organophosphorus pesticides are one of the most consumable poisons. such poisons can enter water sources by different routes. since consuming some drinking water containing an amount of poison higher than the standard level, causes undesirable effects on human health. this research aimed to study the effectiveness of elimi­nating malathion from water by ultraviolet irradiation (uv) ...

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...

In this research zinc sulfide (ZnS) nanoparticles and nanocomposites powders were prepared by chemical precipitation method using zinc acetate and various sulfur sources. The ZnS nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, ultraviolet-visible and fourier transform infra-red. The structure of nanoparticles was studied using X-ray diffraction pattern. The ...

We observed the Seyfert 1 galaxy NGC 3516 twice during the flight of Astro-2 using the Hopkins Ultraviolet Telescope aboard the space shuttle Endeavour in March 1995. Simultaneous X-ray observations were performed with ASCA. Our far-ultraviolet spectra cover the spectral range 820–1840 Å with a resolution of 2–4 Å. No significant variations were found between the two observations. The total spe...