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81.
Anthony Ashmore Riccardo Bartolini Nicolas Delerue 《Central European Journal of Physics》2011,9(4):980-985
Laser-driven Plasma Accelerators (LPA) have successfully generated high energy, high charge electron bunches which can reach
many kA peak current, over short distances. Space charge issues, even in transport lines as simple as a drift section, have
to be carefully taken into account since they can degrade the beam quality, preventing any further application of such electron
beams. We analyse the space charge effects within an electron bunch with numerical simulations in order to assess their effect
on the beam. We use LPA beam parameters published in previous experimental studies. These studies can give an indication of
the working point where space charge can dominate the beam dynamics and has to be taken into account in the application of
such beams. 相似文献
82.
Riccardo Barbieri Paolo Campli Gino Isidori Filippo Sala David M. Straub 《The European Physical Journal C - Particles and Fields》2011,71(12):1812
We study CP asymmetries in rare B decays within supersymmetry with a U(2)3 flavour symmetry, motivated by the SUSY flavour and CP problems, the hierarchies in the Yukawa couplings and the absence
so far of any direct evidence for SUSY. Even in the absence of flavour-blind phases, we find potentially sizable CP violating
contributions to b→s decay amplitudes. The effects in the mixing-induced CP asymmetries in B→ϕK
S
and B→η′K
S
, angular CP asymmetries in B→K
∗
μ
+
μ
− and the direct CP asymmetry in B→X
s
γ can be in the region to be probed by LHCb and next generation B factories. At the same time, these effects in B decays are compatible with CP violating contributions to meson mixing, including
a non-standard B
s
mixing phase hinted by current tensions in the CKM fit mostly between SyKS, eKS_{\psi K_{S}}, \epsilon_{K} and DMBs/DMBd\Delta M_{B_{s}}/\Delta M_{B_{d}}. 相似文献
83.
Riccardo Ruffo Fabio La MantiaColin Wessells Robert A. HugginsYi Cui 《Solid State Ionics》2011,192(1):289-292
The development of lithium ion aqueous batteries is getting renewed interest due to their safety and low cost. We have demonstrated that the layer-structure LiCoO2 phase, the most commonly used electrode material in organic systems, can be successful delithiated and lithiated again in a water-based electrolyte at currents up to 2.70 A/g. The capacity is about 100 mAh/g at 0.135 A/g and can be tuned by cycling the electrode in different potential ranges. In fact, increasing the high cut-off voltage leads to higher specific capacity (up to 135 mAh/g) but the Coulomb efficiency is reduced (from 99.9% to 98.5%). The very good electrode kinetic is probably due to the high conductivity of the electrolyte solution (0.17 Scm− 1 at 25 °C) but this behavior is affected by the electrode load. 相似文献
84.
We prove the existence of small amplitude quasi-periodic solutions for quasi-linear and fully nonlinear forced perturbations of the linear Airy equation. For Hamiltonian or reversible nonlinearities we also prove their linear stability. The key analysis concerns the reducibility of the linearized operator at an approximate solution, which provides a sharp asymptotic expansion of its eigenvalues. For quasi-linear perturbations this cannot be directly obtained by a KAM iteration. Hence we first perform a regularization procedure, which conjugates the linearized operator to an operator with constant coefficients plus a bounded remainder. These transformations are obtained by changes of variables induced by diffeomorphisms of the torus and pseudo-differential operators. At this point we implement a Nash–Moser iteration (with second order Melnikov non-resonance conditions) which completes the reduction to constant coefficients. 相似文献
85.
In this paper the question of finding infinitely many solutions to the problem −Δu+a(x)u=|u|p−2u, in RN, u∈H1(RN), is considered when N≥2, p∈(2,2N/(N−2)), and the potential a(x) is a positive function which is not required to enjoy symmetry properties. Assuming that a(x) satisfies a suitable “slow decay at infinity” condition and, moreover, that its graph has some “dips”, we prove that the problem admits either infinitely many nodal solutions or infinitely many constant sign solutions. The proof method is purely variational and allows to describe the shape of the solutions. 相似文献
86.
87.
Riccardo Molle Donato Passaseo 《Calculus of Variations and Partial Differential Equations》2014,49(1-2):861-907
We present some multiplicity results concerning semilinear elliptic Dirichlet problems with jumping nonlinearities where the jumping condition involves a set of high eigenvalues not including the first one. Using a variational method we show that the number of solutions may be arbitrarily large provided the number of jumped eigenvalues is large enough. Indeed, we prove that for every positive integer $k$ there exists a positive integer $n(k)$ such that, if the number of jumped eigenvalues is greater than $n(k),$ then the problem has at least a solution which presents $k$ peaks. Moreover, we describe the asymptotic behaviour of the solutions as the number of jumped eigenvalues tends to infinity; in particular, we analyse some concentration phenomena of the peaks (near points or suitable manifolds), we describe the asymptotic profile of the rescaled peaks, etc $\ldots $ 相似文献
88.
89.
Wolfgang Bermel Dr. Ivano Bertini Prof. Isabella C. Felli Prof. Riccardo Peruzzini Roberta Pierattelli Prof. 《Chemphyschem》2010,11(3):689-695
Provided that 13C‐detected NMR experiments are either preferable or complementary to 1H detection, we report here tools to determine Cα? C′, C′? N, and Cα? Hα residual dipolar couplings on the basis of the CON experiment. The coupling constants determined on ubiquitin are consistent with the subset measured with the 1H‐detected HNCO sequences. Since the utilization of residual dipolar couplings may depend on the mobility of the involved nuclei, we also provide tools to measure longitudinal and transverse relaxation rates of N and C′. This new set of experiments is a further development of a whole strategy based on 13C direct‐detection NMR spectroscopy for the study of biological macromolecules. 相似文献
90.