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101.
超重元素(新核素)合成研究进展情况分析和展望 总被引:2,自引:0,他引:2
本文在介绍和分析国际、国内在超重元素(新核素)合成实验研究与理论研究进展情况的基础上对我国今后如何从理论与实验的结合上开展超重元素(核)合成研究工作提出一些看法和建议,提供讨论。 相似文献
102.
Let be a bounded, connected linearly convex set in with boundary. We show that the maximal ideal (both in ) and ) consisting of all functions vanishing at is generated by the coordinate functions .
Received: 2 July 2001; in final form: 26 September 2001 / Published online: 28 February 2002 相似文献
103.
Jan J. Slawianowski 《General Relativity and Gravitation》2003,35(5):965-966
104.
Jan Andres Karel Pastor Pavla Šnyrychová 《Journal of Fixed Point Theory and Applications》2007,2(1):153-170
A multivalued version of Sharkovskiĭ’s theorem is formulated for M-maps on linear continua and, more generally, for triangular M-maps on a Cartesian product of linear continua. This improves the main result of [AP1] in the sense that our multivalued
analogue holds with at most two exceptions. A further specification requires some additional restrictions. For instance, 3-
orbits of m-maps imply the existence of k-orbits for all
k ? \mathbbNk \in {\mathbb{N}}
, except possibly for
k ?k \in
{4, 6}. It is also shown that, on every connected linearly ordered topological space, an M-map with orbits of all periods can always be constructed. This demonstrates that Baldwin’s classification of linear continua
in terms of admissible periods [Ba] is useless for multivalued maps. 相似文献
105.
We investigate traces of functions, belonging to a class of functions with dominating mixed smoothness in ℝ3, with respect to planes in oblique position. In comparison with the classical theory for isotropic spaces a few new phenomenona
occur. We shall present two different approaches. One is based on the use of the Fourier transform and restricted to p = 2. The other one is applicable in the general case of Besov-Lizorkin-Triebel spaces and based on atomic decompositions. 相似文献
106.
Olga Ordeig Craig E Banks Trevor J Davies F Javier del Campo Francesc Xavier Mu?oz Richard G Compton 《Analytical sciences》2006,22(5):679-683
Gold ultra-microelectrode arrays are used to explore the electrochemical oxidation of hydroxide ions and are shown to be analytical useful. Two types of ultra-microelectrode arrays are used; the first consist of 256 individual electrodes of 5 microm in radius, 170 of which are electrochemically active in a cubic arrangement which are separated from their nearest neighbour by a distance of 100 microm. The second array compromises 2597 electrodes of 2.5 microm in radius and of which 1550 of which are electrochemically active in a hexagonal arrangement separated by the nearest neighbour by 55 microm. Well defined voltammetric waves are found with peak currents proportional to the concentration of hydroxide ions in the range 50 microM to 1 mM. Detection limits of 20 microM using the 170 ultra-microelectrode and 10 microM with the 1550 ultra-microelectrode array are shown to be possible but with a higher sensitivity of 4 mA M(-1) observed using the 1550 ultra-microelectrode array compared to 1.2 mA M(-1) with the 170 ultra-microelectrode array. 相似文献
107.
Ivan Gutman Sabina Gojak Niko Radulovi? Boris Furtula 《Monatshefte für Chemie / Chemical Monthly》2006,46(2):277-284
In a recent work it was demonstrated that in linear hexagonal chains the distribution of π-electrons into rings (as computed
by means of the Randić–Balaban method) is uniform, irrespective of the nature of the terminal fragments. We now establish that an analogous, yet somewhat
more complex, uniformity in the π-electron distribution exists also in double linear hexagonal chains, as well as in some
other benzenoid systems. 相似文献
108.
The stoichiometric reactions of trimethylaluminum with 2,6‐(MeOCH2)2C6H3OH (LH) revealed compounds L3Al ( 1 ) and L2AlMe ( 2 ). On the other hand reaction of 1 equiv. of LH with trimethylaluminum did not lead to the formation of complex LAlMe2 ( 3 ), rather 2 together with Me3Al were observed as a result of a disproportionation of 3 . Compounds 1 and 2 were characterized by elemental analysis, 1H and 13C NMR spectroscopy and in the case of 1 by X‐ray diffraction. Derivative 2 underwent transmetalation with Ph3SnOH, giving LSnPh3 ( 4 ) as the result of a migration of ligand L from the aluminum to the tin atom. The identity of 4 was established by elemental analysis, 1H, 13C and 119Sn NMR spectroscopy and 1H, 119Sn HMBC experiments. The system 2 and B(C6F5)3 in a 1:1 molar ratio was shown to be active in the polymerization of propylene oxide and ε‐caprolactone. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
109.
Daniel Král’ Jan Kratochvíl Andrzej Proskurowski Heinz-Jürgen Voss 《Discrete Applied Mathematics》2006,154(4):660-672
A mixed hypergraph is a triple (V,C,D) where V is its vertex set and C and D are families of subsets of V, called C-edges and D-edges, respectively. For a proper coloring, we require that each C-edge contains two vertices with the same color and each D-edge contains two vertices with different colors. The feasible set of a mixed hypergraph is the set of all k's for which there exists a proper coloring using exactly k colors. A hypergraph is a hypertree if there exists a tree such that the edges of the hypergraph induce connected subgraphs of the tree.We prove that feasible sets of mixed hypertrees are gap-free, i.e., intervals of integers, and we show that this is not true for precolored mixed hypertrees. The problem to decide whether a mixed hypertree can be colored by k colors is NP-complete in general; we investigate complexity of various restrictions of this problem and we characterize their complexity in most of the cases. 相似文献
110.
Applying a Lindemann like criterion obtained previously by Kierfeld et al. [J. Kierfeld, T. Nattermann, T. Hwa, Phys. Rev. B 55 (1997) 626], we estimate the magnetic field and temperature for a high-Tc superconductor, at which a topologically ordered vortex glass phase becomes unstable with respect to a disorder-induced formation of dislocations. The employed criterion is shown to be equivalent to a conventional phenomenological Lindemann criterion including the values for the numerical factors, i.e., for the Lindemann number. The positional correlation length of the topologically ordered vortex glass is calculated. 相似文献