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971.
All-Union Scientific-Research Institute of Nuclear Power Plants NIIP. Translated from Atomnaya énergiya, Vol. 77, No. 5, pp.
392–402, November, 1994. 相似文献
972.
The short-range order (SRO) structure of a Au-25 at. pct Fe single crystal was studied using wide-angle diffuse synchrotron
X-radiation scattering at room temperature. Two heat treatments were investigated: a 400 °C aging treatment for 2 days and
a 440 °C treatment for 5 days, both preceded by solution treatment in the single-phase field and water-quenched to room temperature.
Evolution of the SRO structure with aging was determined by fitting the two sets of Cowley-Warren (C-W) SRO parameters to
a pair of 140,608-atom models. The microstructures, although quite disordered, showed a trend with aging for an increasing
volume fraction of an Fe-enriched and an Fe-depleted environment. The Fe-enriched environment displayed a preference for Fe
segregation to the {110} and {100} face-centered cubic (fcc) matrix planes. A major portion of the Fe-depleted environment
was found to contain elements (and variations of these elements) of the Dla ordered superstructure. The SRO contained in the Fe-depleted environment may be best described in terms of the standing concentration
wave packet (SCWP) model. This study provides, for the first time, a quantitative real-space view of the atomic arrangements,
which make up both environments in the SRO structure of Au-25 at. pct Fe.
Formerly Graduate Research Assistant, University of Illinois, Urbana, IL. 相似文献
973.
974.
I Prigione P Facchetti E Lanino A Garaventa V Pistoia 《Canadian Metallurgical Quarterly》1993,37(1):40-46
Cultures of both isolated and conjugated explants from early gastrulae of Bufo arenarum were prepared for a study of the development of ventral mesoderm. Only combinations including components of the deep ventral marginal zone and the animal pole successfully differentiated into blood cells (erythrocytes). Histological studies indicated that, while prospective mesodermal cells constituted the only source of such cells, prospective ectodermal cells provided the necessary stimulus for this kind of differentiation. Differentiated cultures, in which the tracer of cell-lineage fluorescein dextran amine was used to label these components, confirmed the above conclusions. These findings are discussed in the context of current concepts about the formation of mesoderm. 相似文献
975.
Dr.-Ing. P. -Ch. Nellner Prof. Dr.-Ing. Dr. tech. E. h. J. Zierep 《Acta Mechanica》1993,101(1-4):45-57
Summary The paper describes a local solution method for the calculation of the interaction between a weak shock front and a turbulent boundary layer on a swept wing. A multiple-deck approach allows the simplification of the governing equations according to the physical character of each deck. The mathematical model is based upon small-perturbation theory. The final boundary-layer solution is given by an iterative coupling of the solutions for each domain. The results are compared with experiments and with other theoretical solutions. 相似文献
976.
B Marchou N Picot P Chavanet JC Auvergnat M Armengaud P Devilliers JE Cerisier FN Marié JL Excler 《Canadian Metallurgical Quarterly》1993,11(14):1383-1385
To determine whether a 3-week hepatitis B (HB) vaccination could achieve protective immunity, 89 healthy non-immunized young adults received three doses of 20 micrograms each of HBs antigen (GenHevac B, Pasteur) and were randomly assigned to schedule A (n = 44): two doses at day 0, one dose at day 21; or schedule B (n = 45): one dose at days 0, 10 and 21. Seroprotection rates (anti-HBs > or = 10 mIU ml-1) for groups A and B respectively were: 23 and 40% at day 21; and 77 and 91% at day 82 (not significant). Anti-HBs geometric mean titres were higher in group B than in group A (p < 0.05) at days 21 (6.4 versus 3.8) and 82 (77.6 versus 33.5). One year after primary vaccination, the seroprotection rate remained as high as 90% in the vaccinees of group B; after boosting all vaccinees had protective levels of anti-HBs antibodies. Thus 3-week HB vaccination with GenHevac B allowed early and durable protective immunity. 相似文献
977.
Troxevasin vacuum-phonophoresis and low-intensity laser irradiation on reflexogenic collar zones demonstrated statistically significant effectiveness. The treatment was used in 94 patients with spondylogenic discirculatory encephalopathy stage I-II. 相似文献
978.
979.
980.
Jürgen P. Rabe 《Advanced materials (Deerfield Beach, Fla.)》1993,5(2):146-148