The anomeric specificity of yeast galactokinase

Anomeric specificity of yeast galactokinase by chromatographic method

Exchange coupling between magnetic layers across non-magnetic superlattices

The oscillation periods of the interlayer exchange coupling are investigated when two magnetic layers are separated by a metallic superlattice of two distinct non-magnetic materials. In spite of the conventional behaviour of the coupling as a function of the spacer thickness, new periods arise when the coupling is looked upon as a function of the number of cells of the superlattice. The new periodicity results from the deformation of the corresponding Fermi surface, which is explicitly related to a few controllable parameters, allowing the oscillation periods to be tuned.Comment: 13 pages; 5 figures; To appear in J. Phys.: Cond. Matte

NNLO predictions for Z-boson pair production at the LHC

We present a calculation of the NNLO QCD corrections to Z-boson pair production at hadron colliders, based on the N-jettiness method for the real radiation parts. We discuss the size and shape of the perturbative corrections along with their associated scale uncertainties and compare our results to recent LHC data at $\sqrt{s}=13$ TeV.Comment: 19 pages, 2 Tables, 4 figures. Version to appear in JHE

Numerical evaluation of two-loop integrals with pySecDec

We describe the program pySecDec, which factorises endpoint singularities from multi-dimensional parameter integrals and can serve to calculate integrals occurring in higher order perturbative calculations numerically. We focus on the new features and on frequently asked questions about the usage of the program.Comment: 11 pages, to appear in the proceedings of the HiggsTools Final Meeting, IPPP, University of Durham, UK, September 201

Analysis of the fluidization behaviour and application of a novel spouted bed\ud apparatus for spray granulation and coating

Spouted beds are well known for their good mixing of the solid phase and for their intensive heat\ud and mass transfers between the fluid phase and the solid phase. Nearly isothermal conditions are\ud enabled which is of advantage for the treatment of granular solid materials in granulation,\ud agglomeration or coating processes. In this work the hydrodynamic behaviour of a novel spouted\ud bed apparatus with two horizontal and slit-shaped gas inlets is investigated by high-frequency\ud recordings of the gas phase pressure fluctuations over the entire bed. The hydrodynamic stable\ud operation domain, which is of importance for operating the apparatus, will be identified and\ud depicted in the Re-G-Ar-diagram by Mitev [1]. Another focus of this work is the simulation of the\ud spouting process by application of a continuum approach in FLUENT 6.2. The effect of the\ud frictional stresses on the hydrodynamic behaviour is examined by performing simulations with and\ud without consideration of friction. The angle of internal friction fi in Schaeffer`s [10] model will be\ud varied and the simulation results will be compared with experiments. It was found that the influence\ud of friction is not very big by application of the quite simple and empirical frictional viscosity model\ud by Schaeffer [10] basing on soil mechanical principles. Also the simulation results under negligence\ud of friction were similar to those under consideration of friction. Another part of this work is the\ud industrial application of the novel spouted bed in granulation and coating processes. Compared to\ud classical fluidized beds, a much narrower particle size distribution, a higher yield and a higher\ud product quality was obtained in the novel spouted be

SecDec-3.0: numerical evaluation of multi-scale integrals beyond one loop

SecDec is a program which can be used for the factorization of dimensionally regulated poles from parametric integrals, in particular multi-loop integrals, and the subsequent numerical evaluation of the finite coefficients. Here we present version 3.0 of the program, which has major improvements compared to version 2: it is faster, contains new decomposition strategies, an improved user interface and various other new features which extend the range of applicability.Comment: 46 pages, version to appear in Comput.Phys.Com

Effect of the liquid layer on the impact behaviour of particles

During a spray granulation process the moisture loading in fluidized beds has a great influence on\ud the inter-particle collision properties and hence on the flow behaviour. To study the influence of the\ud liquid layer as well as granule impact velocity on the impact behaviour free-fall experiments were\ud performed. During these experiments the g-Al2O3 granules were dropped from a predefined height\ud onto a liquid layer on the flat steel wall and the velocity-time curves were obtained using highspeed\ud video recording. The height of the liquid layer was varied from 50 mm to 1 mm. Moreover,\ud the tests were performed at different velocities and viscosities of liquid layer in the range of 1-300\ud mPa∙s. Both distilled water and water solutions of hydroxypropyl methylcellulose with different\ud concentrations (3, 6, 10 mass-%) were used.\ud The obtained restitution coefficients were compared with the experiments performed without liquid\ud film on the surface. For a granule impacted on a liquid film on the wall, the increase of liquid\ud viscosity decreases the restitution coefficient and thickness of liquid layer at which the granule\ud sticks. In the examined velocity range, with decreasing impact velocity the restitution coefficient\ud greatly decreases. To explain the obtained effects the force and energy balances for a particle\ud impacted on a liquid layer on the wall were derived. Both contributions to energy absorption\ud (granule-liquid layer and granule-wall contacts) have been taken into consideratio

NLO predictions for Higgs boson pair production with full top quark mass dependence matched to parton showers

We present the first combination of NLO QCD matrix elements for di-Higgs production, retaining the full top quark mass dependence, with a parton shower. Results are provided within both the POWHEG-BOX and MadGraph5_aMC@NLO Monte Carlo frameworks. We assess in detail the theoretical uncertainties and provide differential results. We find that, as expected, the shower effects are relatively large for observables like the transverse momentum of the Higgs boson pair, which are sensitive to extra radiation. However, these shower effects are still much smaller than the differences between the Born-improved HEFT approximation and the full NLO calculation in the tails of the distributions.Comment: replaced by published version; in addition typos corrected in definition of pole coefficients below Eq.(2.4

Gilbert Damping in Magnetic Multilayers

We study the enhancement of the ferromagnetic relaxation rate in thin films due to the adjacent normal metal layers. Using linear response theory, we derive the dissipative torque produced by the s-d exchange interaction at the ferromagnet-normal metal interface. For a slow precession, the enhancement of Gilbert damping constant is proportional to the square of the s-d exchange constant times the zero-frequency limit of the frequency derivative of the local dynamic spin susceptibility of the normal metal at the interface. Electron-electron interactions increase the relaxation rate by the Stoner factor squared. We attribute the large anisotropic enhancements of the relaxation rate observed recently in multilayers containing palladium to this mechanism. For free electrons, the present theory compares favorably with recent spin-pumping result of Tserkovnyak et al. [Phys. Rev. Lett. \textbf{88},117601 (2002)].Comment: 1 figure, 5page