Flows in 3-edge-connected bidirected graphs

It was conjectured by A. Bouchet that every bidirected graph which admits a nowhere-zero k-flow admits a nowhere-zero 6-flow. He proved that the conjecture is true when 6 is replaced by 216. O. Zyka improved the result with 6 replaced by 30. R. Xu and C. Q. Zhang showed that the conjecture is true for 6-edge-connected graph, which is further improved by A. Raspaud and X. Zhu for 4-edge-connected graphs. The main result of this paper improves Zyka’s theorem by showing the existence of a nowhere-zero 25-flow for all 3-edge-connected graphs.     

Solvating,manipulating, damaging,and repairing DNA in a computer

This work highlights four different topics in modeling of DNA: (i) the importance of water and ions together with the structure and function of DNA; the hydration structure around the ions appears to be the determining factor in the ion coordination to DNA, as demonstrated in the results of our MD simulations; (ii) how MD simulations can be used to simulate single molecule manipulation experiments as a complement to reveal the structural dynamics of the studied biomolecules; (iii) how damaged DNA can be studied in computer simulations; and (iv) how repair of damaged DNA can be studied theoretically. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007     

Direct measurement of gas solubility and diffusivity in poly(vinylidene fluoride) with a high-pressure microbalance

We present solubility and diffusion data for the gases methane and carbon dioxide in the polymer poly(vinylidene fluoride). The polymer was cut from extruded piping intended for use in offshore oil and gas applications. Measurements were carried out using a purpose-built high-pressure microbalance. These properties were determined in the temperature range 80-120 °C and in the pressure range 50-150 bar for methane and 20-40 bar for carbon dioxide. In general, good agreement was obtained for similar measurements reported in the literature. Solubility follows a Henry’s law (linear) dependence with pressure. Diffusion coefficients for each of the gases in the polymer were also measured using the balance. Activation energies for diffusion and heats of solution for the two gases in the polymer were also determined.     

FTIR spectroscopy of ethyl benzoate-titanium tetrachloride complexes with application to supported Ziegler-Natta catalysts

Several methods using linear predictionz-transformation and autoregression have been applied to FTIR spectral analysis to reduce noise and improve resolution of an emission spectrum obtained from the truncated interferogram.     

Maximality of entropy in finite von Neumann algebras

It is shown that the entropy function H(N ₁,…,N _k ) on finite dimensional von Neumann subalgebras of a finite von Neumann algebra attains its maximal possible value H(⋁ℓ=1k N _ℓ) if and only if there exists a maximal abelian subalgebra A of ⋁ℓ=1k N _ℓ such that A=⋁ℓ=1k(A∩N _ℓ). Oblatum 24-IV-1997 & 6-V-1997     

Vibrational analysis and FTIR spectra of seven isotopic congeners of ethyl benzoate including18O carbonyl and ether labelled esters

FTIR spectra of seven isotopic congeners of ethyl benzoate are fitted to a force field with a standard deviation of less than 7 cm^–1. The field has been transferred to ethyl anisate and an equimolar titanium tetrachloride-ethyl benzoate complex with encouraging success. The band at 1280cm^–1 is definitely assigned as mainly an-C-O stretch.     

Mapping cones and separable states

We study mapping cones and their dual cones of positive maps of the \(n\times n\) matrices into itself. For a natural class of cones there is a close relationship between maps in the cone, super-positive maps, and separable states. In particular the composition of a map from the cone with a map in the dual cone is super-positive, and so the natural state it defines is separable.