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61.
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
62.
Lubomír Kubáček 《Mathematica Slovaca》2007,57(1):59-82
In some situations estimates of unknown parameters must be corrected by additional measurements. It is in principle no problem
to calculate the corrected estimates, however, it is of more interest to find formulae for correction itself. The formulae
enable us to design an additional experiment and to judge its usefulness.
The aim of the paper is to find such formulae for several situations.
Supported by the grant of the Council of Czech Government MSM 6 198 959 214. 相似文献
63.
Influence of boric acid on the electrochemical deposition of Ni 总被引:1,自引:0,他引:1
M. Šupicová R. Rozik L. Trnková R. Oriňáková M. Gálová 《Journal of Solid State Electrochemistry》2006,10(2):61-68
The electrolytic deposition of Ni onto a paraffin-impregnated graphite electrode from supporting chloride electrolyte (0.5 mol dm−3 NaCl) adjusted to the required pH using dilute HCl is investigated. The effect of electrolyte composition on the Ni electrodeposition
is studied using linear sweep voltammetry in the cathodic region. An elimination voltammetry procedure was applied to evaluate
the polarization curves. The aim of this work was to deduce the mechanism of Ni reduction in the chloride bath as well as
the influence of boric acid on this. Positively-charged NiCl+ ions were found to be the electroactive particles in the Ni reduction mechanism. The strong competition between the NiCl+, Cl− and H+ ions for active sites at the electrode is discussed. Kinetically-controlled adsorption/desorption processes of various species
were also confirmed using elimination voltammetry with a linear scan. The evolution of gaseous hydrogen, catalyzed by the
freshly-deposited Ni, accompanies the electrodeposition process. The presence of boric acid at a sufficiently high concentration
inhibits the deposition of Ni and, at the same time, improves the morphology and brightness, as well as the adhesion of the
deposited Ni.
Elimination voltammetry with a linear scan is an efficient way to evaluate current–potential curves that reflect the electrodeposition
of one-component Ni coatings. By eliminating selected currents, additional interesting and useful information can be obtained
from voltammetric data. 相似文献
64.
akir Aydoan Mustafa Salam Abdulmecit Türüt 《Journal of Polymer Science.Polymer Physics》2006,44(11):1572-1579
The polypyrrole/p‐InP structure has been fabricated by the electrochemical polymerization of the organic polypyrrole onto the p‐InP substrate. The current–voltage (I–V), capacitance–voltage (C–V), and capacitance–frequency (C–f) characteristics of the PPy/p‐InP structure have been determined at room temperature. The structure showed nonideal I–V behavior with the ideality factor and the barrier height 1.48 and 0.69 eV respectively. C–f measurements of the structure have been carried out using the Schottky capacitance spectroscopy technique and it has been seen that there is a good agreement between the experimental and theoretical values. Also, it has been seen that capacitance almost show a plateau up to a certain value of frequency, after which, the capacitance decreases. The higher values of capacitance at low frequencies were attributed to the excess capacitance resulting from the interface states in equilibrium with the p‐InP that can follow the a.c. signal. The interface state density Nss and relaxation time τ of the structure were determined from C–f characteristics. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1572–1579, 2006 相似文献
65.
Pavol Ševera 《Letters in Mathematical Physics》2006,75(3):273-277
We introduce an affine-invariant version of generating functions of symplectic transformations of affine symplectic spaces,
together with a generalization for other symmetric symplectic spaces. The composition of these functions has a nice connection
with the Moyal product. 相似文献
66.
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
67.
This paper presents the results of plasma temperature and pressure calculations in the parallel plate accelerator during the accelerating process. The plasma pressure is calculated by means in Dalton's law. 相似文献
68.
Zusammenfassung Durch spektrophotometrische Messungen in Dimethylformamid (DMF) werden die Koordinationsformen [CuCl]+ und [CuCl3]– sowie [NiCl]+, [NiCl3]– und [NiCl4]2– nachgewiesen. Bei Nickel(II)-chlorid und Kupfer(II)-chlorid wird Autokomplexbildung diskutiert. Die Solvate [Cu(DMF)4] (ClO4)2 und [Ni(DMF)6] (ClO4)2 werden isoliert.Im Zuge der Untersuchungen über Chlorokomplexe von Ionen der Übergangsmetalle1, 2 in nichtwäßrigen Lösungsmitteln wurden die Spektren der Lösungen von Kupfer(II)- und Nikkel(II)-perchlorat inDMF in Gegenwart verschiedener Mengen Tetraäthylammoniumchlorid aufgenommen.Mit 5 Abbildungen 相似文献
69.
The Radiative Transfer Equation is the nonlinear transport equation
相似文献
70.
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