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81.
The paper completes the investigation of limit distribution of the number of particles at the source of branching in the model of critical catalytic branching random walk on ^dd N {{mathbb Z}^d};d in {mathbb N} . Limit theorems of such kind were established only for d = 1, 2, 3, 4 under the assumption that, at the initial moment, there is a single particle at the source of branching. We prove their analog for d geqslant 5 d geqslant 5 . Moreover, in any dimension, we generalize the previous results by permitting the initial particle to start at an arbitrary point of the lattice.  相似文献   
82.
We propose a new Broyden method for solving systems of nonlinear equations, which uses the first derivatives, but is more efficient than the Newton method (measured by the computational time) for larger dense systems. The new method updates QR or LU decompositions of nonsymmetric approximations of the Jacobian matrix, so it requires O(n 2) arithmetic operations per iteration in contrast with the Newton method, which requires O(n 3) operations per iteration. Computational experiments confirm the high efficiency of the new method.  相似文献   
83.
    
A theoretical approach to study ro-vibrational molecular states from a full nuclear Hamiltonian expressed in terms of normal-mode irreducible tensor operators is presented for the first time. Each term of the Hamiltonian expansion can thus be cast in the tensor form in a systematic way using the formalism of ladder operators. Pyramidal XY3 molecules appear to be good candidates to validate this approach which allows taking advantage of the symmetry properties when doubly degenerate vibrational modes are considered. Examples of applications will be given for PH3 where variational calculations have been carried out from our recent potential energy surface [Nikitin et al., J. Chem. Phys. 130, 244312 (2009)].  相似文献   
84.
    
In the present work cobalt‐doped n‐ and p‐type silicon samples were studied by means of deep level transient spectroscopy (DLTS) and Laplace‐DLTS (LDLTS). We demonstrate that two dominant DLTS peaks previously assigned to a substitutional Co defect have different annealing behaviour and therefore belong to different defects. After wet chemical etching three other peaks (E90, E140 and H160) were observed in the samples. The intensity of the peaks becomes larger in the H‐plasma treated samples. This together with depth profiling demonstrates that the peaks are hydrogen‐related defects. The origin of the peaks will be discussed.  相似文献   
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86.
Modeling of atomic and cyclotron lines in the emergent spectra of rotating neutron stars with various distributions of temperature over the star surface is carried out. General and special relativity effects are taken into account in the radiation transfer calculations. A novel method of analysis based on the Fourier series expansion of the observed spectra over rotation frequencies is proposed. It is shown that the mutual influence of the gravitational bending of light rays and rotation of the star leads to the formation of strong features (sometimes several features at once) in the Fourier-harmonic spectrum, whereas these features remain almost invisible in both the integrated and dynamic spectra. Possible application of the obtained results to the interpretation of absorption features in the spectrum of the single neutron star 1E 1207.4 − 5209 is discussed.  相似文献   
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Journal of Analytical Chemistry - The drift time and ion mobility of imidazole are determined and a procedure for the mathematical processing of spectra is developed. The specific features of...  相似文献   
90.
Synthesis and applications of organotin(II) sulfide ({2,6‐(Me2NCH2)2C6H3}Sn)2(μ‐S) ( 1 ), organotin(II) thiophenolate {2,6‐(Me2NCH2)2C6H3}Sn(SPh) ( 2 ) and organotin(IV) heptasulfide {2,6‐(Me2NCH2)2C6H3}2Sn2S7 ( 3 ) as potential single‐source precursors (SSPs) for the deposition of SnS or SnS2 thin films using a spin‐coating method are reported. Compounds 1 , 2 and 3 differ either by tin oxidation state or by Sn:S ratio (Sn:S = 2:1 in 1 , 1:1 in 2 and 2:7 in 3 ). It is shown that compound 1 is not a suitable SSP for thin‐film fabrication using the spin‐coating process because of its incomplete decomposition at annealing temperature. However, compounds 2 and 3 seem to be promising SSPs for spin‐coating of amorphous semiconducting thin films of SnS and SnS2, respectively. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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