[en] Transition radiation (TR) of a relativistic electron crossing the in surface of a crystal may be scattered by a system of atomic planes. This effect may change essentially the interference between TR waves emitted from in and out surfaces of a crystalline target. The influence of the mentioned effect on total emission properties is studied in this work within the frame of the dynamical diffraction approach

[en] Published in summary form only

[en] This review focuses on recent fruitful findings of dependence of sputtering phenomena on solid-state property and secondary particle species in the field of interaction of MeV-energy heavy ions with matter. Emission mechanism of singly charged ions from non-insulating targets is explained by the Sigmund-Thompson linear cascade model combined with increase of ionization probability by transient electronic excitation. However, emission mechanism of multiply charged ions differs from that of singly charged ions, and can be explained by a combined mechanism of simultaneous recoiling and ionization by the projectile and the Coulomb repulsion by a short-lived ionized track region. Large cluster ions are produced from non-metallic targets. Mostly clusters are emitted directly from solid surface. However, in the case of Al₂O₃, they are produced by coagulation of small molecules in a selvage region near the surface. (author)

[en] Effects of glucocorticoids on HDC in cultured mouse mastocytoma P-815 cells and rat peritoneal mast cells (RPMC) were investigated to explore the role of steroids in inflammatory tissues. DM (1 nM to 10 μM) significantly elevated the histamine content and HDC activity of P-815 cells (37⁰C, 24 hrs), accompanying with a growth retardation of the cells by about 40%. In contrast to histamine, serotonin levels of P-815 cells were decreased by treatment with DM. However, DM had no significant effects on the activities of various enzymes other than HDC present in granules or membrane of P-815 cells. DM-induced increases of histamine and HDC activity were completely suppressed by the addition of cycloheximide and actinomycin D. P-815 cells were found to have the binding sites for ³H-DM in the cytosol (Kd=2.2 nM, 450 sites/cell) and in the nuclei (Kd=0.1 nM, 39 sites/nucleus). Purified HDC from P-815 cells was identified to be an isozyme of mast cell type enzyme (MW=110K, pI=5.4). In contrast, the basal histamine level of cultured RPMC was not affected by treatment of DM, which suppressed histamine release activity induced by DNP-ascaris antiserum by 40%-50%. Histamine-depleted RPMC after degranulation partially recovered histamine level by 50%-60% in the presence of DM. These results showed that glucocorticoids specifically stimulated histamine formation with the increased de novo synthesis of HDC in mast cells

[en] Independent isomer yields of ¹³⁰Sb(5⁺,8^-), ¹³²Sb(4⁺,8^-), ¹³¹Te(3/2⁺,11/2^-) and ¹³³Te(3/2⁺,11/2^-) in the thermal-neutron fission of ²³³U(5/2⁺), ²³⁵U(7/2^-) and ²³⁹Pu(1/2⁺), and those of ¹²⁸Sb(5⁺,8^-) for ²³³U and ²³⁹Pu were measured by the conventional radiochemical method. The mean angular momentum jh/2π of the primary fragments has been deduced from the isomer-yield ratios. The result may indicate that the value of j tends to decrease as the number of neutrons in the Sb and Te isotopes approaches the neutron magic number, and is independent of the angular momentum of the fissioning nucleus. (Auth.)

No abstract available

No abstract available

[en] Transuranium nuclides were produced by irradiating a pellet of natural uranium sulfide in the Japan Testing Reactor (JMTR). After irradiation, a successive separation of uranium, plutonium, americium and curium was carried out. The fractional concentrations of the nuclides ²³⁸Pu, ²³⁹Pu, ²⁴⁰Pu, ²⁴¹Am, ²⁴²Cm and ²⁴⁴Cm were determined by α-ray spectrometry, and those of ²⁴¹Pu and sup(242m)Am were estimated from the build-up of α-emitting daughters, ²⁴¹Am and ²⁴²Cm, respectively. As the yield of ²⁴²Pu was too slight to be detected by α-counting, the neutron activation analysis of the plutonium fraction based on the ²⁴²Pu(n,γ)²⁴³Pu reaction was carried out by γ-ray spectrometry, and it was shown that a few pg of ²⁴²Pu could be determined. A burn-up of ²³⁵U was also estimated by neutron activation analysis. The experimental results are compared with the calculated ones. (author)

No abstract available

[en] The neutral fractions were measured for 50-250 keV hydrogen emerging from a NiSi₂(111) surface at several grazing exit angles (the angle between the outgoing hydrogen and the surface). It was found first that the neutral fractions depend strongly on the exit angle, and the values become close to that for pure Si as the energy and the exit angle of the emitting hydrogen decrease. We compared the experimental results with the ones calculated by assuming that NiSi₂ consists of dense atomic layers of Si and Ni. The best fit is obtained with the structural model in which the topmost layer is composed of Si atoms and the second one is Ni atoms. (Author)