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1.
No analytic solutions of the Schrödinger equation are known for the quartic anharmonic oscillator. We show in this paper that there are closely related modified quartic oscillators with the potential depending on |x| for which analytic solutions for some states exist. These results can be extended to the higher order oscillators 相似文献
2.
Márcio D. Lima Mônica J. de Andrade Viera Skákalová Felipe Nobre Carlos P. Bergmann Siegmar Roth 《固体物理学:研究快报》2007,1(4):165-167
A method for the production of transparent carbon nanotube networks (CNTNs) over transparent substrates was developed. In this method, CNTNs were grown directly in the target surface by applying the catalyst in specific zones of the substrate through lithographic techniques. The networks can be also transferred from the original substrate to other surfaces. The newly grown carbon nanotubes have a very high aspect ratio (>50000). Thus far, networks with an optical transmittance of 94% at 550 nm and a surface resistivity of 3.6 kΩ/sq have been produced. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
3.
4.
A pair of coupled classical oscillators with a general potential and general form of coupling is investigated. For general
potentials, the single-frequency solution is shown to be stable for small excitations. For special potentials, such system
remains stable for an arbitrary excitation. In both cases, the stability does not depend on the form of coupling. Transition
to the instability regime follows from the way how nonlinear potential entrains the energy transfer between the oscillators.
Relation between the existence of multi-frequency quasi-periodic or periodic solutions and the instability of single-frequency
ones is discussed. 相似文献
5.
Spin-flip (paramagnetic) scattering and neutron depolarization studies were performed on Ce2Fe17 in its paramagnetic phase on the Dhruva neutron polarization analysis spectrometer. The absence of normalQ dependence of the scattered spin flip intensity shows that Ce2Fe17 is not a normal paramagnetic and there exist superparamagnetic clusters of sufficiently large dimensions (~100Å). The observed neutron depolarization gives an indication of the dynamics of these Ce2Fe17 superparamagnetic clusters. 相似文献
6.
7.
During irradiation of liquid samples of 1-vinylimidazole, 2-vinylnaphthalene, 2-vinylpyridine, 4-vinylpyridine and 1,1-diphenylethene
with positive muons, radicals of the type MuCH2ĊHAr (Ar=the appropriate aromatic group), and the MuCH2ĊPh2 radical were observed by transverse field μSR; the muon hyperfine couplings are considered in the context of the effectiveness
of the aryl groups in delocalising the unpaired electron. 相似文献
8.
Gašper Jaklič Jernej Kozak Marjeta Krajnc Vito Vitrih Emil Žagar 《Numerical Algorithms》2007,45(1-4):49-60
In this paper, three-pencil lattices on triangulations are studied. The explicit representation of a lattice, based upon barycentric
coordinates, enables us to construct lattice points in a simple and numerically stable way. Further, this representation carries
over to triangulations in a natural way. The construction is based upon group action of S
3 on triangle vertices, and it is shown that the number of degrees of freedom is equal to the number of vertices of the triangulation.
相似文献
9.
Sk. Asrof Ali Yunusa Umar B. F. Abu‐Sharkh Hasan A. Al‐Muallem 《Journal of polymer science. Part A, Polymer chemistry》2006,44(19):5480-5494
The cycloterpolymerizations of single‐, twin‐, and triple‐tailed hydrophobes with hydrophilic monomer N,N‐diallyl‐N‐carboethoxymethylammonium chloride and sulfur dioxide afforded a series of cationic polyelectrolytes (CPEs) in excellent yields. These CPEs, upon the acidic hydrolysis of the pendent ester groups, gave the corresponding pH‐responsive cationic acid salts, which, upon a treatment with sodium hydroxide, were converted to polybetaines (PBs), anionic polyelectrolytes (APEs), and PB/APE polymers containing various proportions of zwitterionic (PB) and anionic fractions (APE) in the polymer chain. At a shear rate of 0.36 s−1 at 30 °C, salt‐free water solutions of the CPEs (2 g/dL) containing 8, 4, and 2.67 mol % of the single‐, twin‐, and triple‐tailed hydrophobes (all having 8 mol % octyloxy tails) had apparent viscosity values of 70, 2800, and 396,000 cps, respectively. The PB/APE polymer with a ratio of 33:67 for the zwitterionic and anionic fractions in the polymer chain gave the highest viscosity value. The superior viscosity behavior of the polymers containing the triple‐tailed hydrophobe was attributed to the blocky nature of the comonomer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5480–5494, 2006 相似文献
10.
Juan Pablo Trelles Emil Pfender Joachim Heberlein 《Plasma Chemistry and Plasma Processing》2006,26(6):557-575
The dynamics of the electric arc inside a direct current non-transferred arc plasma torch are simulated using a three-dimensional, transient, equilibrium model. The fluid and electromagnetic equations are solved numerically in a fully coupled approach by a multiscale finite element method. Simulations of a torch operating with argon and argon–hydrogen under different operating conditions are presented. The model is able to predict the operation of the torch in steady and takeover modes without any further assumption on the reattachment process except for the use of an artificially high electrical conductivity near the electrodes, needed because of the equilibrium assumption. The results obtained indicate that the reattachment process in these operating modes may be driven by the movement of the arc rather than by a breakdown-like process. It is also found that, for a torch operating in these modes and using straight gas injection, the arc will tend to re-attach to the opposite side of its original attachment. This phenomenon seems to be produced by a net angular momentum on the arc due to the imbalance between magnetic and fluid drag forces. 相似文献