Background: Monte Carlo simulations play a vital role in the calculation of the necessary shielding both for neutrons and photons. Advanced and simple shielding materials against neutron and gamma rays were compared by simulation using the MCNB4B Monte Carlo code. The simulations were carried out for the three common neutron sources, namely the 252Cf, the 241Am/Be and the DD neutron generator w...

background: boron neutron capture therapy (bnct) is a very promising treatment for patients suffering gliobastoma multiforme, an aggressive type of brain cancer, where conventional radiation therapies fail. thermal neutrons are suitable for the direct treatment of cancers which are located at near-tissue-surface deep-seated tumors need harder, epithermal neutron energy spectra. materials and me...

The possibilities and limitations of hardening silicon semiconductor devices to the high neutron and gamma radiation levels (greater than 1016 neutrons/cm 2 (i Mev eq.) and greater than 108 rads (Si) required for the NERVA nuclear engine development are discussed. A comparison is made of the high dose neutron and garmna hardening potential of bipolar, metal insulator semiconductor (MIS), and ju...

A new approach to fast-neutron dosimeq is described. It involves circulating a liquid with dissolved chemicals between a localized neutron field and a remote area where neutron-induced radioactivities are measured continuously. This approach employs reactions whch generate relatively short-lived radioactive byproducts. Sensitivity to the neutron energy spectrum is achieved by choosing several r...

Calibration curves for fission spectrum neutrons and other high LET radiations are scarce in cytogenetic dosimetry and particularly for Prematurely Condensed Chromosome Rings (PCC-ring). Here we analyzed the behavior of the PCC-ring frequency and PCC index after neutron irradiation in a broad dose interval from 1 to 26 Gy. PCC-rings were induced in lymphocytes with Calyculin A. 6455 PCC cells i...

(41)Ca is produced mainly by absorption of low-energy neutrons on stable (40)Ca. We used accelerator mass spectrometry (AMS) to measure (41)Ca in enamel of 16 teeth from 13 atomic bomb survivors who were exposed to the bomb within 1.2 km from the hypocenter in Hiroshima. In our accompanying paper (Wallner et al., Radiat. Res. 174, 000-000, 2010), we reported that the background-corrected (41)Ca...