The Regularity of Critical Points of Polyconvex Functionals

In this paper we are concerned with the question of regularity of critical points for functionals of the type eq1 We construct a smooth, strongly polyconvex eq2, and Lipschitzian weak solutions eq3 to the corresponding Euler-Lagrange system, which are nowhere C¹. Moreover we show that F can be chosen in such a way that these irregular weak solutions are weak local minimisers.     

Unambiguous identification of three beta-decaying isomers in 70Cu

Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations.     

A novel PLD configuration for deposition of films of improved quality: a case study of carbon nitride

Pairs of carbon nitride films have simultaneously been deposited by ArF excimer laser ablation of a graphite target in the 2–50 Pa nitrogen pressure window, with one substrate parallel and 48-mm apart from the target in the traditional on-axis geometry, and the other placed in the target plane. The pressure dependence of the apparent growth rate, defined as the measured thickness per number of pulses, is significantly different for the two geometries. In the traditional geometry the growth rate is almost constant at around 0.0035 and 0.023 nm/pulse for 1 and 5 Jcm^-2, respectively, while in the target plane it increases proportionally to the logarithm of the nitrogen pressure for both fluences. Complementary surface characterisation by atomic force microscopy reveals that the films grown in the novel geometry, referred to as inverse pulsed laser deposition, are made up of smaller grains and appear to be more compact. PACS 68.37.Ps; 68.55.-a; 81.15.Fg     

Beta-eudesmol, a new sesquiterpene component in intact and organized root of chamomile (Chamomilla recutita)

Gas chromatography (GC) and GC-mass spectrometry are used to identify a new sesqiterpene, beta-eudesmol, which seems to be a characteristic essential oil component of the intact and in vitro organized root of chamomile [Chamomilla recutita (L.) Rauschert]. It is identified on three types of stationary phases by GC. The confirmation of identity is carried out by comparison of mass spectra with those reported in the literature and measured from a reference compound. The percentage evaluation of the oil component is made by area normalization, on the basis of three parallel measurements. Among the cultivated and wild chamomile species examined, the wild species from the areas of Szeghalom contain the highest quantity of beta-eudesmol (9.25% in the total essential oil).     

Independent yields of Kr and Xe isotopes in the photofission of heavy nuclei

The yields of Kr (A = 87–93) and Xe (A = 138–143) primary fission fragments produced in ²³²Th, ²³⁸U, and ²⁴⁴Pu photofission upon the scission of a target nucleus and neutron emission were measured in an experiment with bremsstrahlung from electrons accelerated to 25 MeV by a microtron, and the results of these measurements are presented. The experimental procedure used involved the transportation of fragments that escaped from the target by a gas flow through a capillary and the condensation of Kr and Xe inert gases in a cryostat at liquid-nitrogen temperature. The fragments of all other elements were retained with a filter at the capillary inlet. The isotopes of Kr and Xe were identified by the γ spectra of their daughter products. The mass-number distributions of the independent yields of Kr and Xe isotopes are obtained and compared with similar data on fission induced by thermal and fast neutrons; the shifts of the fragment charges with respect to the undistorted charge distribution are determined. Prospects for using photofission fragments in studying the structure of highly neutron-rich nuclei are discussed.     

Finite temperature spectral function of the σ meson from large <Emphasis Type="Italic">N</Emphasis> expansion

The spectral function of the scalar-isoscalar channel of the O(N) symmetric linear σ model is studied in the broken symmetry phase. The investigation is based on the leading order evaluation of the self-energy in the limit of large number of Goldstone bosons. We describe its temperature-dependent variation in the whole low temperature phase. This variation closely reflects the trajectory of the scalar-isoscalar quasi-particle pole. In the model with no explicit chiral symmetry breaking, we studied also the corresponding dynamical exponent near the critical point.     

Three limit cycles for a first‐order exothermic chemical reaction in a continuous stirred‐tank reactor

We study a first‐order exothermic chemical reaction in a continuous stirred‐tank reactor modelled by a 3‐parameter family of vector fields in . We prove that there exist regions in which contain points that depend on parameters such that the chemical reaction has 0, 1, 2, or 3 small amplitude limit cycles that surround the origin. We conclude that this model can reach two stable small amplitude limit cycles. Finally, we show that one of these regions contains the point in the parameter space considered by Gurel and Lapidus [6] who proved numerically the existence of one stable limit cycle. This revised version was published online in July 2006 with corrections to the Cover Date.     

Separation of Fumonisins by OPLC

JPC – Journal of Planar Chromatography – Modern TLC - Fumonisins were produced by six strains of Fusarium moniliforme and Fusarium proliferatum on inoculated rice culture. For study of...