Subglacial drainage processes at a High Arctic polythermal valley glacier

Peer reviewedPublisher PD

Observations on a viscoseal in a transparent housing - The prevention of leakage and breakdown

Leakage and breakdown prevention in transparently housed viscoshaft seal with visual observatio

Statistics of precursors to fingering processes

We present an analysis of the statistical properties of hydrodynamic field fluctuations which reveal the existence of precursors to fingering processes. These precursors are found to exhibit power law distributions, and these power laws are shown to follow from spatial $q$-Gaussian structures which are solutions to the generalized non-linear diffusion equation.Comment: 7 pages incl. 5 figs; tp appear in Europhysics Letter

Dynamics of short polymer chains in solution

We present numerical and analytical results describing the effect of hydrodynamic interactions on the dynamics of a short polymer chain in solution. A molecular dynamics algorithm for the polymer is coupled to a direct simulation Monte Carlo algorithm for the solvent. We give an explicit expression for the velocity autocorrelation function of the centre of mass of the polymer which agrees well with numerical results if Brownian dynamics, hydrodynamic correlations and sound wave scattering are included

Dynamic correlations in stochastic rotation dynamics

The dynamic structure factor, vorticity and entropy density dynamic correlation functions are measured for Stochastic Rotation Dynamics (SRD), a particle based algorithm for fluctuating fluids. This allows us to obtain unbiased values for the longitudinal transport coefficients such as thermal diffusivity and bulk viscosity. The results are in good agreement with earlier numerical and theoretical results, and it is shown for the first time that the bulk viscosity is indeed zero for this algorithm. In addition, corrections to the self-diffusion coefficient and shear viscosity arising from the breakdown of the molecular chaos approximation at small mean free paths are analyzed. In addition to deriving the form of the leading correlation corrections to these transport coefficients, the probabilities that two and three particles remain collision partners for consecutive time steps are derived analytically in the limit of small mean free path. The results of this paper verify that we have an excellent understanding of the SRD algorithm at the kinetic level and that analytic expressions for the transport coefficients derived elsewhere do indeed provide a very accurate description of the SRD fluid.Comment: 33 pages including 16 figure

The influence of soil steaming on some properties of the soil and on the growth and heading of winter glasshouse lettuce. I. Changes in chemical and physical properties.

Soil steaming caused an increase of 33 ppm mineral N. There was no significant effect on water-soluble P2O5. The influence of steaming on buffer-soluble Mg content varied with the treatment but there seemed to be a negative correlation with the P content. Steaming enhanced K solubility and increased buffer-soluble Mn content. Fe and Al soluble in buffer solution were slightly increased. 44 references. (Abstract retrieved from CAB Abstracts by CABI’s permission

The influence of soil steaming on some properties of the soil and on the growth and heading of winter glasshouse lettuce. II. The reaction of the crop.

Soil steaming increased fresh and dry weights and N and Mn contents of the plants. Leaching the steamed soil caused a further increase in Mn content but decreased yields and N content. The addition of straw to the steamed soil did not affect growth or N content but it reduced the Mn content. Plants grown on steamed soil had darker coloured leaves and a greater incidence of leaf margin necrosis and bad heading than plants grown on unsteamed soil. See also Sous Fertil. 33 [1230]. (Abstract retrieved from CAB Abstracts by CABI’s permission