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191.
Petar Petrov 《Monatshefte für Mathematik》2006,147(2):165-171
In this work we investigate polynomials of maximal (minimal) arc-length in the interval [−1, 1] amongst all monic polynomials
of fixed degree n with n real zeros in [−1, 1]. 相似文献
192.
M. Trhlík B. Sedlák V. P. Parfenova A. L. Erzinkyan G. M. Gurevich S. V. Topalov P. Malinský V. N. Pavlov 《Hyperfine Interactions》1989,50(1-4):749-754
The low temperature nuclear orientation of54Mn in Pt99.95Fe0.05, Pt99.9Fe0.1, Pt99Fe1 and Pt88Fe12 has been studied in the temperature range 12–50 mK and in the external magnetic field range 0–1.2 T. The strong temperature
and external magnetic field dependence of the effective fieldB
eff on54Mn has been observed even in the range where the host itself is magnetically saturated. This behaviour is interpreted by noncollinearity
of the Mn magnetic moments with respect to the macroscopic magnetisation direction. 相似文献
193.
Angular anisotropy of the alpha emission from241Am nuclei oriented by magnetic hyperfine interaction
Angular anisotropy of the alpha emission from241Am nuclei oriented by magnetic hyperfine interaction at low temperatures in ZrFe2-host have been observed. The sign of the anisotropy indicates unambiguously the enhanced alpha emission from the poles of241Am nucleus. The value of magnetic hyperfine field on241Am nuclei have been estimated from the temperature dependence of the anisotropy. 相似文献
194.
Let be a triangle in
and let
be the set of its three medians. We construct interpolants to smooth functions using transfinite (or blending) interpolation on
The interpolants are of type f(1)+g(2)+h(3), where (1,2,3) are the barycentric coordinates with respect to the vertices of . Based on an error representation formula, we prove that the interpolant is the unique best L1-approximant by functions of this type subject the function to be approximated is from a certain convexity cone in C3().Received: 17 December 2003 相似文献
195.
We suggest a construction that, given an orbital diffeomorphism between two Hamiltonian systems, produces integrals of them. We treat geodesic equivalence of metrics as the main example of it. In this case, the integrals commute; they are functionally independent if the eigenvalues of the tensor g
ig¯j
are all different; if the eigenvalues are all different at least at one point then they are all different at almost each point and the geodesic flows of the metrics are Liouville integrable. This gives us topological obstacles to geodesic equivalence. 相似文献
196.
Petar Grujić 《Physics letters. A》1983,96(5):233-235
The dependence of an ionization function on the total energy near the break-up threshold has been derived making use of the classical theory. The threshold exponent for the triple ionization by electron impact on neutral target assumes the value κ = 3.525. 相似文献
197.
Theoretical predictions and experimental results for nanosized modification of metal (Au), semiconductor (Si), or dielectric (soda lime glass) substrates using near-electromagnetic field enhancement in the vicinity of gold nanoparticles are presented. The near field properties for the system consisting of an isolated gold nanoparticle or nanoparticle aggregate deposited on the substrates, which is irradiated by electromagnetic wave, are investigated using Finite Difference Time Domain Simulation technique. The influence of the substrate material on the near field distribution characteristics is predicted. The results reveal that the field on the substrate surface is enhanced in the three investigated cases, but its spatial distribution and magnitude depend on the substrate material. In the case of the metal and semiconductor substrate the enhanced near field is strongly localized in the vicinity of the contact point with the particle, in an area with diameter smaller than the particle's one. The intensity of the enhanced field on the glass is more than an order of magnitude lower than the case of using silicon substrate. The properties of the near field on the substrate surface also depend on the particle arrangement. For a two-dimensional gold nanoparticle array, when the particles are closely arrayed, the intensity of the enhanced field on the substrate surface is minimal. With the increase of the interparticle distance the near field intensity increases. The validity of the obtained theoretical results is confirmed experimentally. 相似文献
198.
We prove local existence and uniqueness of weak solutions of the Camassa–Holm equation with periodic boundary conditions in various spaces of low-regularity which include the periodic peakons. The proof uses the connection of the Camassa–Holm equation with the geodesic flow on the diffeomorphism group of the circle with respect to the L 2 metric. 相似文献
199.
Emilia D. Naydenova Petar T. Todorov Kolio D. Troev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1315-1320
A series of new cycloalkanespiro-5-hydantoin phosphonic acids have been synthesized and characterized. The mixture of [(2,4-dioxo-1,3-diazaspiro-alkane-3-yl)-methyl]phosphonic acids and [(2,4-dioxo-1,3-diazaspiro-alkane-1,3-diyl)dimethyl]diphospho-nic acids was obtained from cycloalkanespiro-5-hydantoins, formaldehyde, and phosphorus trichloride in a molar ratio of 1:2:2, by a procedure modified by us. Their structures were proved by means of IR, 1H, 13C{1H} and 31P NMR spectroscopy. 相似文献
200.
We show that the class of locally finite varieties omitting type 1 has the following properties. This class is:
- definable by an idempotent, linear, strong Mal’cev condition in a language with one 4-ary function symbol;
- not definable by an idempotent, linear, strong Mal’cev condition in a language with only one function symbol of arity strictly less than 4;
- definable by an idempotent, linear, strong Mal’cev condition in a language with two 3-ary function symbols;
- not definable by an idempotent, linear, strong Mal’cev condition in a language with function symbols of arity less than 4 unless at least two of the symbols have arity 3.