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31.
In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region.  相似文献   
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Muon spin rotation measurements are reported for GdSr2Cu2RuO8, a material with an onset temperature for superconductivity of about 45 K (which is virtually the same for its superconducting sister compounds Sr2YRu1? u Cu u O6 and Gd2? z Ce z Sr2Cu2RuO10). The data indicate two magnetic ordering transitions, at about 15 K and about 130 K, in addition to the Gd ordering transition known to occur at about 2.6 K. We tentatively attribute the 130 K transition to Ru and the 15 K transition to Cu ordering, effectively ruling out any superconducting mechanism based on fluctuating magnetic moments, which are frozen below about 15 K. If there is only one mechanism of high-temperature superconductivity, then the three facts that (i) all three sister compounds have essentially the same onset T c for superconductivity and (ii) all three of these compounds contain SrO layers but (iii) only two of the three compounds, GdSr2Cu2RuO8 and Gd2? z Ce z Sr2Cu2RuO10 (and not Sr2YRu1? u Cu u O6) contain cuprate planes imply that the superconducting layers of all three compounds must be the common SrO layers, and not the cuprate planes (which do not occur in Cu-doped Sr2YRuO6). Otherwise the coincidence of onset temperatures must be an accident, and there must be at least two mechanisms of high-T c superconductivity: one for doped Sr2YRuO6 and another for cuprate-plane superconductivity.  相似文献   
34.
Riemannian cubics are curves in Riemannian manifolds M that are critical points for the L 2 norm of covariant acceleration, and are already rather well studied as elementary curves for interpolation problems in engineering. In the present paper the L 2 norm is replaced by the L norm, which may be more appropriate for some applications. However it is more difficult to derive the analogue of the Euler-Lagrange equation for the L norm, requiring techniques from optimal control, and the resulting necessary conditions take a different form. These necessary conditions are examined when M is a sphere or a bi-invariant Lie group, and some examples are given.  相似文献   
35.
The new results concerning the continuity of holomorphically contractible systems treated as set functions with respect to non-monotonic sequences of sets are given. In particular, continuity properties of Kobayashi and Carathéodory pseudodistances, as well as Lempert and Green functions with respect to sequences of domains converging in the Hausdorff metric are delivered.  相似文献   
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Background  

Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)].  相似文献   
38.
Complementary but independent medium-energy and low-energy ion scattering studies of the (0001) surfaces of V(2)O(3) films grown on Pd(111), Au(111) and Cu(3)Au(100) reveal a reconstructed full O(3)-layer termination creating a VO(2) surface trilayer. This structure is fully consistent with previous calculations based on thermodynamic equilibrium at the surface during growth, but contrasts with previous suggestions that the surface termination comprises a complete monolayer of vanadyl (V=O) species.  相似文献   
39.
Luke  G. M.  Kiefl  R. F.  Kreitzman  S. R.  Brewer  J. H.  Noakes  D. R.  Celio  M.  Keitel  R.  Uemura  Y. J.  Harshman  D. R.  Jaccarino  V. 《Hyperfine Interactions》1986,31(1-4):29-34
We report the observation of μ+ Level-Crossing Resonances (LCR's) in the ordered phase of an antiferromagnetic material. Two LCR's were observed in MnF2 as a function of longitudinal magnetic field in the temperature range between 10K and 65K. Both are attributed to a muon in an interstitial octahedral-like site. The low field resonance is attributed to a muon-nuclear spin flip-flop transition involving the two nearest neighbour19F nuclei. The high field resonance occurs when the applied field cancels the local hyperfine field on the muon. The positions and widths of the LCR's were seen to scale with the sublattice magnetization.  相似文献   
40.
Researchers from the Savannah River Technology Center, the Center for Applied Isotope Studies (CAIS) and Sampling Systems have developed a prototype Field Deployable Tritium Analysis System (FDTAS) for near-real-time measurements of environmental levels of tritium in ground and surface water. The device consists of a modified liquid scintillation counter coupled to an automatic sampler which incorporates on-line water purification. The FDTAS has been field tested at several Savannah River Site locations and has produced results comparable to laboratory analyses for low concentrations of tritium. Figures of merit obtained in the field include an average tritium background count rate of 1.5 counts per minute (cpm), tritium detection efficiency of ≈25%, and a detection limit of <10 Bq/l for a 100 minute count.  相似文献   
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