CMBEASY:: an Object Oriented Code for the Cosmic Microwave Background

We have ported the cmbfast package to the C++ programming language to produce cmbeasy, an object oriented code for the cosmic microwave background. The code is available at www.cmbeasy.org. We sketch the design of the new code, emphasizing the benefits of object orientation in cosmology, which allow for simple substitution of different cosmological models and gauges. Both gauge invariant perturbations and quintessence support has been added to the code. For ease of use, as well as for instruction, a graphical user interface is available.Comment: 7 pages, 5 figures, matches published version, code at http://www.cmbeasy.or

Small Business Capitalization Patterns

This study investigates the initial capitalization and financing patterns of recently established (new) and established (old) small businesses in Iowa. Analysis of survey responses indicates that significant differences exist between these two groups of firms. Specifically, new firms are found to have relied more heavily on debt financing than old firms. This suggests that new firms with high debt loads are likely not to survive and become old firms

The Effects of Hydrofluoric Acid Addition on the Hydrothermal Synthesis of Templated Uranium Sulfates

The effects of addition of a second acid source (HF) on the formation of uranium sulfates are described in this article. -- author-supplied description

Early Dark Energy Cosmologies

We propose a novel parameterization of the dark energy density. It is particularly well suited to describe a non-negligible contribution of dark energy at early times and contains only three parameters, which are all physically meaningful: the fractional dark energy density today, the equation of state today and the fractional dark energy density at early times. As we parameterize Omega_d(a) directly instead of the equation of state, we can give analytic expressions for the Hubble parameter, the conformal horizon today and at last scattering, the sound horizon at last scattering, the acoustic scale as well as the luminosity distance. For an equation of state today w_0 < -1, our model crosses the cosmological constant boundary. We perform numerical studies to constrain the parameters of our model by using Cosmic Microwave Background, Large Scale Structure and Supernovae Ia data. At 95% confidence, we find that the fractional dark energy density at early times Omega_early < 0.06. This bound tightens considerably to Omega_early < 0.04 when the latest Boomerang data is included. We find that both the gold sample of Riess et. al. and the SNLS data by Astier et. al. when combined with CMB and LSS data mildly prefer w_0 < -1, but are well compatible with a cosmological constant.Comment: 6 pages, 3 figures; references added, matches published versio

Structural diversity in organically templated uranium sulfates

The potential of organic amine templates to direct the synthesis of metal sulfate frameworks has been investigated. Eight novel uranyl sulfates have been prepared using a templated uranyl sulfate precursor under hydrothermal conditions. The topologis of the isolated phases vary from the molecular (0-D), to chains (1-D) to layered (2-D) frameworks. [N4C6H 22]2[(UO2)2(SO4) 6] (USO-10) is molecular or zero-dimensional. Two different types of onedimensional uranyl-containing chains have been observed. [N2C 4H12][UO2(H2O)(SO4) 2 (USO-3), [N2C5H14]-[UO 2(H2O)(SO4)2] (USO-4) and [N 2C3H12][UO2(H2O)(SO 4)2 (USO-9) contain chains based upon a [UO 2(SO4)4/2] backbone. [N2C 10H10][UO2(SO4)2· H2O (USO-6) and [N2C6H18][(UO 2)2(H2O)3(SO4) 3] (USO-7) contain chains based upon a [UO2(SO 4)3/3] backbone. Two layered or two-dimensional compounds, [N2C6H14][UO2(H2O) (SO4)2 (USO-5) and [N2C3H 5]2[(UO2)2(SO4) 3] (USO-8) have also been isolated. All the new phases have been characterised using a range of physical techniques including single crystal X-ray structure analysis. © The Royal Society of Chemistry 2003

Observational constraints on the dark energy density evolution

We constrain the evolution of the dark energy density from Cosmic Microwave Background, Large Scale Structure and Supernovae Ia measurements. While Supernovae Ia are most sensitive to the equation of state $w_0$ of dark energy today, the Cosmic Microwave Background and Large Scale Structure data best constrains the dark energy evolution at earlier times. For the parametrization used in our models, we find $w_0 < -0.8$ and the dark energy fraction at very high redshift $\Omega_{early} < 0.03$ at 95 per cent confidence level.Comment: 5 pages, 10 figure