Neutron-beam-shaping assembly for boron neutron-capture therapy

A neutron-beam-shaping assembly consisting of a moderator, a reflector, and an absorber is used to form a therapeutic neutron beam for the boron neutron-capture therapy of malignant tumors at accelerator neutron sources. A new structure of the moderator and reflector is proposed in the present article, and the results of a numerical simulation of the neutron spectrum and of the absorbed dose in a modified Snyder head phantom are presented. The application of a compositemoderator and of a composite reflector and the implementation of neutron production at the proton energy of 2.3MeVare shown to permit obtaining a high-quality therapeutic neutron beam.     

Boron Neutron Capture Therapy

Physics of Atomic Nuclei - Fundamentals of boron neutron capture therapy of malignant tumors are outlined, and the current status of the development of epithermal-neutron sources on the basis of...     

Radiochemical determination of some trace elements in biological materials using short-lived isotopes

A radiochemical procedure for the consecutive separation of vanadium and molybdenum, copper, manganese, rubidium and potassium is proposed for the analysis of biological materials. Vanadium and molybdenum are extracted together with 0.1% BPHA solution in toluene, copper followed by manganese are extracted as diethyldithio-carbamate complexes with chloroform and rubidium and potassium are precipitated as tetraphenylborates.     

New Heusler alloys with a metamagnetostructural phase transition

Investigations of new ferromagnetic shape-memory Ni-Mn-Z Heusler alloys (Z = In, Sn, Sb) are reviewed. Experimental data are described and explained on the assumption that these alloys undergo a phase transition from the ferromagnetic to the antiferromagnetic state (metamagnetic transition). The results of theoretical studies of the phase diagrams of these alloys are considered with regard to the possible change in the character of magnetic ordering (from ferromagnetic to antiferromagnetic) and interaction of the structural martensitic transformation with the metamagnetic transition.