Protactinium-231 – New burnable neutron absorber

I.1.3. Study of Advanced Candu Fuel Radioactivity Evolution with Irradiation by Using Burnable Neutron

CHAPTER FOUR PROTACTINIUM Boris

Protactinium, element 91, is one of the most rare of the naturally occurring elements and may well be the most difficult of all to extract from natural sources. Protactinium is, formally, the third element of the actinide series and the first having a 5f electron. The superconducting properties of protactinium metal provide clear evidence that Pa is a true actinide element (Smith et al., 1979)....

A global scavenging and circulation ocean model of thorium-230 and protactinium-231 with realistic particle dynamics (ProThorP 0.1)

In this paper, we set forth a 3-D ocean model of the radioactive trace isotopes Th and Pa. The interest arises from the fact that these isotopes are extensively used for investigating particle transport in the ocean and reconstructing past ocean circulation. The tracers are reversibly scavenged by biogenic and lithogenic particles. Our simulations of Th and Pa are based on the NEMO–PISCES ocean...

Secondary neutron dose measurement for proton eye treatment using an eye snout with a borated neutron absorber

BACKGROUND We measured and assessed ways to reduce the secondary neutron dose from a system for proton eye treatment. METHODS Proton beams of 60.30 MeV were delivered through an eye-treatment snout in passive scattering mode. Allyl diglycol carbonate (CR-39) etch detectors were used to measure the neutron dose in the external field at 0.00, 1.64, and 6.00 cm depths in a water phantom. Seconda...

A New Em-wave Absorber Using Functional Electromagnetic Cell Material

This paper describes a new functional electromagnetic cell material (EMCM) for EMC use. This novel material is composed of passive or active micro-electronic circuit elements and they are connected with loss or conductive wirings. If it is composed of active circuit elements, this material is able to exhibit a special feature of changeable characteristics of EM-wave absorber. As an example of E...