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11.
Ch. F. D. McCoy 《Algebra and Logic》2002,41(5):295-305
The notion of
3
0
-categoricity in linear orderings and Boolean algebras is examined. We provide a proof for the fact that there are uncountably many relatively
3
0
-categorical linear orderings, and furnish a proof of another fact which suggests that the (unrelatively)
3
0
-categorical linear orderings may be very difficult to classify. In stark contrast to these results for linear orderings, a complete classification of the relatively
3
0
-categorical Boolean algebras is given. 相似文献
12.
B.R. Lewis J.H. Carver T.I. Hobbs D.G. McCoy H.P.F. Gies 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,22(2):213-221
Experimental oscillator strengths and predissociation linewidths have been measured at room temperature for the (2-0) to (5-0) Schumann-Runge bands of molecular oxygen using the Adelaide 6 m vacuum ultraviolet monochromator operated at a resolution of about 0.06 Å. Photoelectric detectors were used to measure the ultraviolet absorption at normally two different gas pressures for 37 groups of rotational lines, and the resulting data were interpreted using an equivalent width type of analysis. The variation with N″ of the oscillator strengths within each band was found to be smaller than that measured earlier for the higher vibrational bands. Measured oscillator strengths agree well with previously accepted values except for the (3-0) band, while the linewidths of the present work agree well with recent theoretical values for the (3-0) and (4-0) bands but are larger for the (2-0) and (5-0) bands. A modification was performed on the parameters of a recent theoretical predissociation model to produce excellent overall agreement between experimental and theoretical linewidths from ν' = 2 to 14. The present work provides results which can be used to construct accurate synthetic absorption profiles for studies of the atmospheric absorption of ultraviolet radiation by the Schumann-Runge bands. 相似文献
13.
Densely Continuous Forms in Vietoris Hyperspaces 总被引:2,自引:0,他引:2
R. A. McCoy 《Set-Valued Analysis》2000,8(3):267-271
For countably paracompact normal spaces X and locally compact separable metric spaces Y, a characterization is given for the closure of the set of densely continuous forms from X to Y in the hyperspace of nonempty closed subsets of X × Y under the Vietoris topology. This shows that for such X having no isolated points, every closed subset of X × R that is dense over X can be Vietoris approximated by a semicontinuous function on X. 相似文献
14.
15.
16.
17.
Liu ZQ McCoy BK Wang ST Pindak R Caliebe W Barois P Fernandes P Nguyen HT Hsu CS Wang S Huang CC 《Physical review letters》2007,99(7):077802
Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C*(alpha) phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C*(FI2) phase intervenes in the smectic-C*(alpha) phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers. 相似文献
18.
19.
We compare Aut(Q), the classical automorphism group of a countable dense linear order, with Aut
c
(Q), the group of all computable automorphisms of such an order. They have a number of similarities, including the facts that every element of each group is a commutator and each group has exactly three nontrivial normal subgroups. However, the standard proofs of these facts in Aut(Q) do not work for Aut
c
(Q). Also, Aut(Q) has three fundamental properties which fail in Aut
c
(Q): it is divisible, every element is a commutator of itself with some other element, and two elements are conjugate if and only if they have isomorphic orbital structures. 相似文献
20.
A set-valued mapping F from a topological space X to a topological space Y is called a cusco map if F is upper semicontinuous and F(x) is a nonempty, compact and connected subset of Y for each x ∈ X. We denote by L(X), the space of all subsets F of X × ℝ such that F is the graph of a cusco map from the space X to the real line ℝ. In this paper, we study topological properties of L(X) endowed with the Vietoris topology.
The second author is supported by the SPM fellowship awarded by the Council of Scientific and Industrial Research, India. 相似文献