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F Ditroi

Publications and source records attributed to F Ditroi.

7 recordsLinked to original sources
PubMed2006

Experimental studies of the deuteron-induced activation cross-sections on natAg.

Excitation functions were measured for the (nat)Ag(d,x)(105,106m,110m)Ag, (nat)Ag(d,x)(107,109)Cd and (27)Al(d,x)(24)Na reactions by the stacked-foil activation technique and high-resolution gamma-spectroscopy over the energy range 0.44-40 MeV. The thick target integral yields were deduced using the measured cross-sections. No experimental data on the (nat)Ag+d process are available in the literature above 27 MeV. The nuclides (105)Ag, (106m)Ag and (109)Cd produced with deuteron induced activation of natural silver have suitable yields and decay characteristics important for thin layer activation (TLA) analysis. The cross-section for the production of (107)Cd and (109)Cd is significantly large. Therefore, the Ag+d process can be an efficient route for the production of isotope with a medium energy accelerator. The results of the model calculation using the TALYS code are not consistent with the present data. A large shift in the incident energy is found in TALYS calculations.

Journal Article↗
PubMed2005

Experimental studies on excitation functions of the proton-induced activation reactions on silver.

Excitation functions were measured for the production of 106m,105Ag, 103,101,100Pd, 105,102,101m,100,99Rh and 97Ru via proton-induced activation reactions on natural silver using a stacked foil technique in the energy range 11-80 MeV. The residual activity measurements were carried out nondestructively by the high-resolution HPGe gamma-ray spectroscopy. Thick target integral yields were deduced using the measured cross-sections from the respective threshold energies of the investigated reactions up to 80 MeV. The present work gives new results for the investigated radionuclides. The data in MENDL-2P deduced with the theoretical model code ALICE-IPPE are consistent in shape with the measured values, but show disagreement in magnitude.

Journal Article↗
PubMed2005

Experimental studies on excitation functions of the proton-induced activation reactions on yttrium.

Proton-induced activation cross-sections were measured for the (89)Y(p,x)(89,88,86)Zr, (89)Y(p,x)(88,87,87 m,86)Y, (89)Y(p,x)(85,83,82)Sr and (89)Y(p,x)(84,83)Rb reactions by a stacked foil technique in the energy range 15-80 MeV which was covered by two separate measurements for 15-50 and 32-80 MeV energy range with 50 and 80 MeV incident protons. The differences between the results of two irradiations were found within 6% in the overlapping energy regions. The production yields for the long-lived products like (88)Zr, and (88)Y are significantly larger than that of (nat)Mo+p, (nat)Nb+p and (nat)Zr+p processes. The productions of the medical isotopes, (85)Sr and (83)Sr are also effective by Y+p process using an 80 MeV beam. Thick target integral yields were also deduced using the measured cross-sections. The (87)Y, (88)Y, (88)Zr and (89)Zr radionuclides have suitable yields and decay characteristics important for thin-layer activation (TLA) analysis.

Journal Article↗
PubMed2004

Separation of potential and kinetic electron emission for grazing impact of multiply charged Ar ions on a LiF(001) surface.

Projectile time-of-flight spectra and the number of emitted electrons have been determined in coincidence for grazing scattering of slow (0.45 keV/u) multiply charged Ar ions from an atomically clean and flat LiF(001) surface. By relating projectile energy loss to kinetic electron emission we were able to determine contributions from potential electron emission even in the presence of a considerable number of kinetically excited electrons. Our results suggest a practically complete use of the available potential energy for electron emission during grazing scattering in sharp contrast to findings for the normal incidence case.

Journal Article↗
PubMed2004

Experimental studies on the proton-induced activation reactions of molybdenum in the energy range 22-67 MeV.

The production cross-sections of (99,93m)Mo, (96,95,95m,94)Tc, (96,95,92m,90)Nb, (89,88,86)Zr and (88,87,86)Y radionuclides for proton-induced reactions on molybdenum were measured with molybdenum targets of natural isotopic composition using a stacked-foil activation technique in the energy range 22-67 MeV. The thick target integral yields were also deduced for each reaction using the measured cross-sections from the respective threshold up to 67 MeV. The results have given new data for all of the investigated radionuclides. The results of the present experiment showed excellent agreement with the earlier reported data in the lower energy region.

Journal Article↗
PubMed1986

Ovarian function immediately after the menarche.

Estrone and pregnanediol-glucuronide values of early morning urine samples collected from young girls in the perimenarche were determined by radioimmunological technique. A total of 58 teenage girls started collecting urine samples after their menarche at various times. Of these, 9 completed collection within 100 days of the onset of the first menstrual period. In 3 cases, insignificant changes in estrone and pregnanediol levels were noted. Normal estrone values were found in 3 cases together with pregnanediol levels suggestive of ovulation. In 2 further cases the possibility of ovulation without follicular release was suggested. The results indicate that ovarian activity is unpredictable immediately following the menarche. Between very low levels of sexual steroid hormone production and those normally observed in adult females, all transitional values could be found.

Adolescent↗