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Gamma-radiation from the reactions of 28 MeV and 26 MeV3He-ions on the209Bi target has been studied by means of Ge(Li) detectors. Individual observed prompt -ray transitions have been assigned to the corresponding reactions. The results of previous studies of the209At nucleus have been verified and completed. Two new levels at energies of 640 keV and 1270·5 keV have been introduced. Additionally, 15 new transitions have been observed which could belong to209At. The209At level structure is discussed in terms of nuclear models.  相似文献   
54.
Influence of Coriolis coupling on excitation of some Nilsson states in155Gd,157Gd and167Er by inelastic scattering of 12·1 MeV deuterons is analysed. Expanded Nilsson potential with hexadecapolar deformation is used for the model calculations. Theoretical values of reduced transition probability,B(E2) are compared with experimental ones.  相似文献   
55.
Work-hardening curves of single crystals of iron and its alloys with 0·5 and 0·9 wt.% Si and paths of the tensile axis of specimens during deformation were investigated. Single crystals oriented for single glide were deformed in tension at temperatures 113, 201, 295 and 403 K at a nominal strain rate of 5·5×10?5 sec?1. It appears that with increasing silicon content (a) the transition between the high-temperature regime of plastic deformation (characterized by three-stage work-hardening) and the low-temperature regime is shifted to lower temperatures, (b) stage I-hardening is enhanced and (c) the flow stress level increases. These observations are explained by strong solution hardening of iron by silicon atoms which suppresses the differences between mobilities of screw and non-screw dislocations, increases the flow stress level and consequently the density of primary dislocations. As a result of this the latent hardening in the secondary slip system increases and stage I extends to a large strain.  相似文献   
56.
The dependence of the flow stress and the slip band density on the plastic strain has been measured at 201 K, 293 K and 363 K. The growth of deformation concentrated in an average slip band has been stated. The types of obstacles acting against the rise and development of a slip band and the temperature dependence of the strain hardening in AgCl crystals are discussed. An equation stating the dependence of the flow stress on the slip band density is presented. The hardening in AgCl crystals is classified as the stage III — hardening.  相似文献   
57.
Magnetics structures of powdered orthorhombic R(Cu, Ni)2 compounds (R = heavy rare earth) determined by neutron diffraction are described. The influence of magnetocrystalline anisotropy and exchange interactions on the type of magnetic ordering is discussed.Dedicated to Academician Vladimír Hajko on the occasion of his 65th brithday.We would like to express our thanks to Professor P. Luká for continual interest and encouragement and to . Zajac and V. Sechovský for many fruitfull discussions.  相似文献   
58.
In the present paper we report the first experimental results on ac and dc conductivity and permittivity of adenine hemisulphate hydrate and adenine sulphate measured at atmospheric and high hydrostatic pressures. For both materials ac conductivity is of s type, where:s 1·1· Room temperature dc conductivity of adenine hemisulphate hydrate equals approximately 5×10–15 –1 cm–1 with an activation energy of 0·86 eV; dc conductivity of adenine sulphate is less than 10–16 cm–1. On the basis of these measurements and those carried out at high pressure, it is concluded that conductivity of adenine hemisulphate hydrate is of electronic type.The authors wish to thank Dr. J. Zachová for the preparation of adenine salts single crystals.  相似文献   
59.
This study deals with potential treatment of spent NTA-containing decontamination solutions for final disposal. The method proposed is based on the degradation of organic substances followed by the separation of radionuclides. The influence of various parameters (pH value, irradiation time, temperature, catalyst amount, type and various combinations of catalysts) on photocatalytic degradation of NTA has been studied. Photo-Fenton reagent (Fe3+/H2O2) as a homogenous catalyst was found to be much more efficient than the TiO2-based heterogeneous catalyst Degussa P25. Under optimum conditions NTA in a simulant of a spent decontamination solution without or with hydrazine could be degraded within 5 or 9 hours, respectively. The study of sorption properties of a series of absorbers revealed that radiostrontium and radiosilver can be effectively removed from the simulant of a spent decontamination solution even in the presence of NTA, while total NTA degradation is necessary for effective radiocobalt separation.  相似文献   
60.
The JINR (Dubna)-IN2P3 (France) Collaboration project aimed at the α, β γ, spectroscopy of the transfermium element isotopes using heavy-ion beams of the U-400 cyclotron and the modernized recoil separator VASSILISSA was launched at Dubna. During the first full-scale experiment in September–October 2004, nobelium and lawrencium isotopes produced in the 48Ca + 207,208Pb → 255,256No* and 48Ca + 209Bi → 257Lr* reactions were studied. The text was submitted by the authors in English.  相似文献   
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