A direct comparlson Is made of the mass spectra of several involatile compounds obtained by using 252Cf ission fragment lonlratlon and iow-energy Ion bombardment using klloelectronvol! K+ and Cs’ ions. The comparisons were made on the same samples mounted on the same folk and mass determinations were made by using the time-of-flight principle. A very hlgh degree of slmllarity was observed In th...

2014 It has been shown recently that fast heavy ions can induce a mild desorption of organic molecules deposited on a thin foil, when passing through the foil. A time of flight mass spectrometer, originally developed to identify the mass of radioactive nuclei, has been slightly transformed to allow the determination of the mass of large molecules. The desorption of the molecules is at the prese...

BACKGROUND In neutron interaction with matter and reduction of neutron energy due to multiple scatterings to the thermal energy range, increasing the probability of thermal neutron capture by neutron captures makes dose enhancement in the tumors loaded with these materials. OBJECTIVE The purpose of this study is to evaluate dose distribution in the presence of 10B, 157Gd and 33S neutron captu...

Sequences of antigenic determinants were identified by limited proteolysis of peptide antigens bound to an immobilized monoclonal antibody and direct molecular weight determination of the monoclonal antibody-bound peptide fragments by 252Cf plasma desorption mass spectrometry. The epitope peptides to the monoclonal antibody h453 [Burger, R., Zilow, G., Bader, A., Friedlein, A. & Naser, W. (1988...

This study was undertaken to investigate the biological effect of monoenergetic neutrons on human lymphocyte DNA and chromosomes. Monoenergetic neutrons of 2.3, 1.0, 0.79, 0.57, 0.37 and 0.186 MeV were generated, and 252Cf neutrons and 60Co gamma-rays were also used for comparison. Biological effect was evaluated two ways. The RBE values with the comet assay were estimated as 6.3 and 5.4 at 0.3...

Introduction: The commercial 252Cf sources are too large in size and clinical applications of neutron brachytherapy (NBT) are limited to a small number of intracavitary treatments of cervical cancers. Recently, under the Cooperative Research and Development Agreement (CRADA) with Isotron Inc., the Oak Ridge National Laboratory (ORNL) encapsulated a new medical 252Cf sources, c...

background: prompt gamma neutron activation analysis (pgnaa) is known as a non-invasive technique capable of measuring elemental concentration in voluminous samples in a short period of time. also it is a valuable diagnostic tool for total body elemental measurements. 252cf and 241am-be sources which are usually used in this method, generate not only neutrons, but also emit high-energy and unwa...

The prompt neutron and γ emission from primary fission fragments are calculated for thermal neutron induced fission of 235U and 239Pu and for spontaneous fission of 252Cf using a Monte Carlo Hauser-Feshbach approach for the evaporation of the excited fission fragments. Remaining free model parameters, such as excitation energy sharing and initial spin distribution, are determined by comparison ...