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1.
2.
The neutrino-electron scattering in a dense degenerate magnetized plasma under the conditions μ 2 > 2eBμE is investigated. The volume density of the neutrino energy and momentum losses due to this process are calculated. The results we have obtained demonstrate that plasma in the presence of an external magnetic field is more transparent for neutrino than for non-magnetized plasma. It is shown that neutrino scattering under conditions considered does not lead to the neutrino force acting on plasma.  相似文献   
3.
Ab initio calculations of core-ionization spectra of the anion-molecule Cl-CO cluster are performed. Particular attention is paid to the investigation of charge-transfer screening processes accompanying core ionization of the CO molecule in the cluster. The charge-transfer processes are very efficient and favored by the presence of a low-lying unoccupied pi* orbital in CO capable of accepting an electron from Cl-. The O1s(-1) and C1s(-1) core-ionization spectra are calculated and compared. Both reveal a breakdown of the quasiparticle picture of core ionization caused by the charge-transfer processes. Remarkable differences between these two spectra are found which manifest themselves in distinct intensity distributions in the prominent low-energy spectral bands. The underlying reason for these differences is elucidated and linked with the preference of the pi* orbital to localize mainly on carbon. Core-ionization spectra of anion-molecule clusters are very sensitive to the type of the molecule involved as the comparative analysis of the O1s(-1) core-ionization spectra of the Cl-CO and Cl-H(2)O clusters show.  相似文献   
4.
Bicyclic cyclopentafuranols were formed by photoinitiated radical cyclization of allyl- and propinyloxymethyl substituted cyclopentanones with high regioselectivity. The irradiations were carried out at a wavelength of 300 nm in aprotic solvents such as benzene and acetonitrile. We could also show that reductive photoinduced electron transfer (PET) of the propynyloxymethyl substituted cyclopentanone 5 does not lead to any cyclization. The starting materials were synthesized in good yields following known procedures.  相似文献   
5.
Ultrathin glycine-ice films (nanolayers) have been prepared in ultrahigh vacuum by condensation of H(2)O and glycine at 110 K and 150 K on single crystalline Al(2)O(3) surfaces and have been investigated by temperature programed thermal desorption, x-ray photoelectron spectroscopy, and work function measurements. Various layer architectures have been considered, including glycine-on-ice, ice-on-glycine, and mixed glycine-ice nanolayers. Low coverages of adsorbed glycine molecules on amorphous ice surfaces suppress the amorphous-to-crystalline phase transition in the temperature range 140-160 K in near-surface regions and consequently lead to a lower desorption temperature of H(2)O molecules than from pure ice layers. Thicker glycine overlayers on ice provide a kinetic restriction to H(2)O desorption from the underlying ice layers until the glycine molecules become mobile and develop pathways for water desorption at higher temperature (>170 K). Ice overlayers do not wet glycine film surfaces, but the glycine molecules on ice are sufficiently immobile at 110 K, so that continuous glycine overlayers form. In mixed glycine-ice nanolayers the glycine phase displays hydrophobic behavior and a phase separation takes place, with the accumulation of glycine near the surfaces of the films.  相似文献   
6.
We study several basic dispersive models with random periodic initial data such that the different Fourier modes are independent random variables. Motivated by the vast physics literature on related topics, we then study how much the Fourier modes of the solution at later times remain decorrelated. Our results are sensitive to the resonances associated with the dispersive relation and to the particular choice of the initial data.  相似文献   
7.
Abstract

It has been known more than for 100 year that triethylphosphine forms the 1:1 adducts with carbon disulfide and isothiocyanates. However, little is know on the reaction of the adducts and the formation of reactive alkylidenephosphoranes was recently reported by the reaction of adducts with electron-poor double bonds.  相似文献   
8.
In this note we consider the Schrödinger equation on compact manifolds equipped with possibly degenerate metrics. We prove Strichartz estimates with a loss of derivatives. The rate of loss of derivatives depends on the degeneracy of metrics. For the non-degenerate case we obtain, as an application of the main result, the same Strichartz estimates as that in the elliptic case. This extends Strichartz estimates for Riemannian metrics proved by Burq-Gérard-Tzvetkov to the non-elliptic case and improves the result by Salort for the degenerate case. We also investigate the optimality of the result for the case on 𝕊3 × 𝕊3.  相似文献   
9.
We prove that the Cauchy problem for the KP-I equation is globally well-posed for initial data which are localized perturbations (of arbitrary size) of a non-localized (i.e. not decaying in all directions) traveling wave solution (e.g. the KdV line solitary wave or the Zaitsev solitary waves which are localized in x and y periodic or conversely).  相似文献   
10.
We present a general result of transverse nonlinear instability of 1d solitary waves for Hamiltonian PDE's for both periodic or localized transverse perturbations. Our main structural assumption is that the linear part of the 1-d model and the transverse perturbation “have the same sign”. Our result applies to the generalized KP-I equation, the Nonlinear Schrödinger equation, the generalized Boussinesq system and the Zakharov–Kuznetsov equation and we hope that it may be useful in other contexts.  相似文献   
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