Alpha Radiation-Induced Luminescence by Am-241 in Aqueous Nitric Acid Solution

When exposed to air, alpha particles cause the production of light by exciting the molecules surrounding them. This light, the radioluminescence, is indicative of the presence of alpha radiation, thus allowing for the optical sensing of alpha radiation from distances larger than the few centimeters an alpha particle can travel in air. While the mechanics of radioluminescence in air and other gas compositions is relatively well understood, the same cannot be said about the radioluminescence properties of liquids. Better understanding of the radioluminescence properties of liquids is essential to design methods for the detection of radioactively contaminated liquids by optical means. In this article, we provide radioluminescence images of Am-241 dissolved in aqueous nitric acid ( HNO 3 ) solution and present the recorded radioluminescence spectrum with a maximum between 350 nm and 400 nm , and a steep decrease at the short wavelength side of the maximum. The shape of the spectrum resembles a luminescence process rather than Cerenkov light, bremsstrahlung, or other mechanisms with broadband emission. We show that the amount of light produced is about 150 times smaller compared to that of the same amount of Am-241 in air. The light production in the liquid is evenly distributed throughout the sample volume with a slight increase on the surface of the liquid. The radioluminescence intensity is shown to scale linearly with the Am-241 concentration and not be affected by the HNO 3 concentration.

Reducing the Loss of Nitrogen in Athmosphere by Granular Urea

One of the main objectives for the future agriculture is to achieve high crop yields but also to maintain and improve soil quality. In 1995, the European Fertilizer Manufacturers Association (EFMA) prepared eight Booklets on Best Available Techniques (BAT) in response to the proposed EU Directive on integrated pollution prevention and control (IPPC Directive). In this Booklet it is show that ammonium nitrate is used extensively as a nitrogenous fertilizer. It is made exclusively by the reaction between gaseous ammonia and aqueous nitric acid, the production of which are covered in EFMA BAT Booklets 1 and 2 respectively. Reseeding of grassland may increase the mineralisation of organic material and lead to a greater amount of mineral nitrogen in soil, which can be leached during the winter-period.