Wave functions of 0+ levels in 38Ca

A simple model of the first three 0⁺ levels in ³⁸Ca gives a good account of the excitation energies and (³He, n) cross sections. The hamiltonian derived is reasonable and the mixing is similar to that needed for other nearby nuclei.     

Monochromatic Sinks in <Emphasis Type="Italic">k</Emphasis>-Arc Colored Tournaments

Let T be a tournament on n vertices whose arcs are colored with k colors. A 3-cycle whose arcs are colored with three distinct colors is called a rainbow triangle. A rainbow triangle dominated by any nonempty set of vertices is called a dominated rainbow triangle. We prove that when \(n\ge 5\), if T does not contain a dominated rainbow triangle and all 4- and 5-cycles of T are near-monochromatic, then T has a monochromatic sink. We also prove that when \(n\ge 4\), if T does not contain a dominated rainbow triangle and all 4-cycles are monochromatic, then T has a monochromatic sink. A semi-cycle is a digraph C that either is a cycle or contains an arc xy such that \(C-xy+yx\) is a cycle. We prove that if \(n\ge 4\) and all 4-semi-cycles of T are near-monochromatic, then T has a monochromatic sink. We also show if \(n\ge 5\) and all 5-semi-cycles of T are near-monochromatic, then T has a monochromatic sink.     

电感耦合等离子体原子发射光谱法测定钛酸钡纳米粉体中7种杂质元素

钛酸钡纳米粉体样品用盐酸溶解,在所得样品溶液中用电感耦合等离子体原子发射光谱法测定了以氧化物存在于样品中的7种杂质元素(包括镁、锶、钾、钠、铝、硅及铁),对测定的光谱条件进行了试验并优化达到上述各元素的测定上限为0.1%(质量分数).测得方法的检出限(3S/b)为(单位μg·L-1):2.0(铝),1.0(铁),20.0(钾),0.2(镁),4.0(钠),3.0(硅)及0.5(锶).应用此方法分析了两件实样,所得结果的相对标准偏差(n=6)小于等于2.0%,对其中4种杂质元素(镁、钾、钠和锶)同时用HG/T 3587-1999标准中的方法作分析校核,所得结果与此方法结果一致.     

Adsorbate influence on the coercive field of ultrathin Co/Cu{1 1 0}

We report on experimental coercive field measurements for ultrathin films of Co on Cu{1 1 0}, revealing a complex dependence upon the surface coverage of oxygen and hydrogen adatoms. With reference to first-principles calculations, we rationalise this behaviour in terms of initial reaction with surface contaminants and/or adsorption at defects, followed by (in the case of oxygen) subsequent surface ordering and eventual formation of surface oxide.     

Structural and magnetic properties of ultrathin epitaxial Fe films on GaAs(001) and related semiconductor substrates

This article presents a review of the structural and magnetic properties of ultrathin epitaxial Fe films on GaAs(001) and related semiconductor substrates. Interest in these systems and Fe/GaAs(001) in particular has increased significantly over the last two decades, largely due to the emergence of the field of magnetoelectronics. Since then numerous studies of molecular beam epitaxy of Fe on GaAs(001) have been carried out, making it by far the best researched Fe/semiconductor(001) system. Issues such as magnetic anisotropy in the ultrathin regime, however, remain controversial with contradictory reports in the literature giving rise to considerable controversy within the field. By carefully scrutinizing the enormous amount of literature published on Fe/GaAs(001) so far and analysing these results within the wider context of Fe/semiconductor(001) systems, this article tries to settle some of these controversial issues, hence providing a long overdue ‘common denominator' for research in this area.     

Magnetic measurements of suspended functionalised ferromagnetic beads under DC applied fields

In this work, a simple technique to obtain the hysteresis loops of magnetic beads (Spherotech Inc.) in liquid suspension is presented. The magnetic measurements were taken in a DC Magnetic Property Measurement System (MPMS-SQUID sensor). Samples were based on ferromagnetic beads (surface-functionalized NH₂, mean diameter 4.32 μm) prepared in three conditions: dry, suspended in sucrose solution and in suspension after functionalization with fluorophore. Special small containers (1.3 cm long) made of non magnetic plastic were designed to hold the beads in liquid. The results indicate that the bead's remnant magnetization is half of the value at maximum applied field in all cases. However, due to the additional degrees of rotational freedom, beads suspended in a liquid do not present coercivity. The use of ferromagnetic beads and magnetic elements of different architectures for applications in bioassays is also discussed.     

Competing ferri- and antiferromagnetic phases in geometrically frustrated LuFe2O4

We present a detailed study of magnetism in LuFe(2)O(4), combining magnetization measurements with neutron and soft x-ray diffraction. The magnetic phase diagram in the vicinity of T(N) involves a metamagnetic transition separating an antiferro- and a ferrimagnetic phase. For both phases the spin structure is refined by neutron diffraction. Observed diffuse magnetic scattering far above T(N) is explained in terms of near degeneracy of the magnetic phases.     

Measurements of the angular distributions in the decays B→K(*)μ(+)μ(-) at CDF

We report an indirect search for nonstandard model physics using the flavor-changing neutral current decays B→K(*)μ(+)μ(-). We reconstruct the decays and measure their angular distributions, as a function of q(2)=M(μμ)(2)c(2), where M(μμ) is the dimuon mass, in ppˉ collisions at √s=1.96 TeV using a data sample corresponding to an integrated luminosity of 6.8 fb(-1). The transverse polarization asymmetry A(T)(2) and the time-reversal-odd charge-and-parity asymmetry A(im) are measured for the first time, together with the K* longitudinal polarization fraction F(L) and the muon forward-backward asymmetry A(FB) for the decays B(0)→K(*0)μ(+)μ(-) and B(+)→K(*+)μ(+)μ(-). The B→K*μ(+)μ(-) forward-backward asymmetry in the most sensitive kinematic regime, 1≤q(2)<6 GeV(2)/c(2), is measured to be A(FB)=0.29(-0.23)(+0.20)(stat)±0.07(syst), the most precise result to date. No deviations from the standard model predictions are observed.