Damping in a dilute Bose gas is investigated using a mean-field approximation which describes the coupled oscillations of condensate and non-condensate atoms in the collisionless regime. Explicit results for both Landau and Beliaev damping rates are given for non-uniform gases. In the case of uniform systems we obtain results for the damping of phonons both at zero and finite temperature. The i...

The pyrolysis of the crude glycerol from a biodiesel production plant was investigated by thermogravimetry coupled with Fourier transform infrared spectroscopy. The main gaseous products are discussed, and the thermogravimetric kinetics derived. There were four distinct phases in the pyrolysis process of the crude glycerol. The presence of water and methanol in the crude glycerol and responsibl...

Bentonite-based engineered barriers are a key component of many repository designs for the confinement high-level radioactive waste and spent fuel. Given complexity interaction phenomena affecting barrier, coupled hydro-mechanical (HM) thermo-hydro-mechanical (THM) numerical analyses potentially useful tool better understanding their behaviour. In this context, Task (INBEB) was undertaken to st...

Contents 1. Introduction 2. Stress-induced lubricant degradation 3. Basic equations governing the fluid elastohydrodynamic lubrication (EHL) of line and point contacts 3.1. Equations of fluid motion 3.2. Contact surface displacements in line and point lubricated contacts 4. Steady isothermal EHL problems for lightly loaded non-conformal line contacts 5. Steady isothermal EHL problems for heavil...

Waste cork granules of Quercus cerris bark were subjected to isothermal and non-isothermal slow pyrolysis. The heat the reaction, as well yields properties biochar, bio-oil, pyrolysis gas investigated by thermogravimetric analysis, FT-IR, CHN elemental higher heating value (HHV) determinations, scanning electron microscopy (SEM), chromatography (GC). was carried out in a semi-batch reactor usin...

Simulations were carried out using penalty finite element analysis with bi-quadratic elements to investigate the influence of uniform and non-uniform heating of bottom wall within a trapezoidal enclosure of various inclination angles ðuÞ. Parametric study has been carried out for a wide range of Rayleigh number ðRaÞ ð10 6 Ra 6 10Þ, Prandtl number ðPrÞ ð0:026 6 Pr 6 988:24Þ and Darcy number ðDaÞ...

Abstract. We describe the probabilistic physics of rarefied particle motions and deposition on rough hillslope surfaces. The energy balance involves gravitational heating with conversion potential to kinetic energy, frictional cooling associated particle–surface collisions, an apparent preferential low-energy particles. Deposition probabilistically occurs in relation distribution states whose s...