Experimental Data

L'alliage de titane est generalement utilise pour les pieces structurelles aeronautiques ayant une taille importante et ainsi que des parois minces tout en devant resister a des efforts considerables. L'usinage de ces pieces est difficile avec les methodes classiques telles que le fraisage, car les forces de coupe sont elevees et les parois minces peuvent etre facilement deformees. L'usinage de l'alliage de titane (Ti6Al4V) par un procede utilisant un jet d'eau abrasif (AWJ) peut potentiellement etre utilise pour remplacer les methodes d'usinage conventionnelles. Cependant, la comprehension des differents aspects de ce procede est insuffisante pour autoriser son industrialisation. Cette these presente un modele de prevision de la profondeur usinee dans deux cas de direction du jet : un jet perpendiculaire a la surface de la piece et un jet incline. Dans un premier temps, la comprehension du processus d'enlevement de matiere et de la qualite de surface obt...

We present a comparison between the finite-element and the lattice-Boltzmann method for simulating fluid flow in a SMRX static mixer reactor. The SMRX static mixer is a piece of equipment with excellent mixing performance and it is used in highly efficient chemical reactors for viscous systems like polymers. The complex geometry of this mixer makes such 3D simulations nontrivial. An excellent agreement between the results of the two simulation methods and experimental data was found.

Aluminium is a third group element according to the periodic table. Chemically it is a reactive metal often forming complexes within its binary alloys. In the present work we have dealt with the impact of eigenvalues on the superconducting state parameter viz. the electron-phonon coupling strength of this metal. We have also dealt with the same for two binary alloys of it viz. aluminium-magnesium and aluminium-zinc. For this purpose we have computed the non-local screened form factor for each of them. Initially the orthogonalised plane wave parameter has been taken as unity. Thereafter Vashishta-Singwi form of exchange and correlation is employed. The core energy eigenvalues of Herman-Skillman have been used. Our results are quite satisfactory for the metal as well as its present alloys. Our computation reveals that the superconducting state parameter can be reasonably reproduced by Harrison’s first principle pseudopotential technique along with McMillan’s formalism provided a prope...

In the present work we have considered the antimony-indium liquid alloy which shows anomaly as regards its heat of mixing and the concentration fluctuations in the long-wavelength limit. On the other hand, the free energy of mixing and the entropy of mixing are found to be symmetric about the equi-atomic composition. Such alloying behaviour has been tried to explain on the basis of conformal solution model. This is a statistical mechanical model based on the formation of complex within the liquid alloy. In this model besides the interaction between unlike atoms, that between each constituent element and the complex too is taken into account. In course of theoretical treatment the activity of antimony is also computed for different concentrations. Our results indicate that Sb-In alloys are thermodynamically most stable around the equi-atomic composition. Key words: Binary liquid alloy; Conformal solution model; Free energy of mixing; Activity; Heat of mixing; Entropy of mixing; Conce...

For the first time, the production of Δ0 (1232) resonances has been analyzed in minimum bias n+12C collisions at 4.2GeV/c. The value of the mass and width of the Δ0 resonances as well as the fraction of the negative pions coming from Δ0 decay obtained in this work in n+12C collisions coincide within the uncertainties with those extracted earlier in d+12C collisions at 4.2GeV/c per nucleon. The inclusive cross-section for production of Δ0 (1232) resonances in n+12C collisions at 4.2GeV/c is estimated to be σincl = 57 ± 3mb. Production of Δ0 resonances in n+12C collisions at 4.2GeV/c has been investigated separately in regions of fragmentation of the target and projectile. The mass of the Δ0 (1232) proved to be the same within the statistical errors in the target and projectile fragmentation regions. The width of the invariant mass spectrum of Δ0 excited in the projectile region proved to be considerably larger than that in the target fragmentation region, coinciding within statistical errors with that obtained in collisions of free nucleons. The results of the previous experiments, in which production of Δ resonances is investigated in the whole phase space (without separating the target and projectile fragmentation regions), can be approximately regarded as the mean values of Δ parameters, averaged over those in the target and projectile fragmentation regions.
Keywords:Δ 0 (1232) production; relativistic nuclear collisions; hadron-nucleus collisions; neutron-carbon collisions.
PACS Number(s): 25.10.+s, 25.40.−h

This work deals with the experimental analysis of multiphase flows during the process of sheet disintegration at Hollow Cone Nozzles. The characterization of surface waves and their propagation is based on the analysis of the sheet movement using multiple 1-dimensional fibre sensors. Each sensor is made of multi-mode PMMA fibers with an outer diameter of 250 micron. The main concept of the measuring technique exploits the Fresnel effect to detect the phase-change on the fibre tip, which is caused by the movement of the liquid sheet along 1-dimensional fibre-arrays. The wavelength, the wave growth rate, the amplitude and sheet velocity in main flow direction of the moving sheet have been analyzed with 8 and 15 mm - orifice nozzles. The Wavelet analysis of the sheet oscillation shows dominating oscillation frequencies within the range of 10 < f < 500 Hz at each flow condition and nozzle geometry within the range of 0.03 < ∆p < 0.16 MPa differential pressure. There is also ...

The transporter associated with antigen processing (TAP) represents a focal point in the immune recognition of virally or malignantly transformed cells by translocating proteasomal degradation products into the endoplasmic reticulum–lumen for loading of MHC class I molecules. Based on a number of experimental data and the homology to the bacterial ABC exporter Sav1866, we constructed a 3D structural model of the core TAP complex and used it to examine the interface between the transmembrane and nucleotide-binding domains (NBD) by cysteine-scanning and cross-linking approaches. Herein, we demonstrate the functional importance of the newly identified X-loop in the NBD in coupling substrate binding to downstream events in the transport cycle. We further verified domain swapping in a heterodimeric ABC half-transporter complex by cysteine cross-linking. Strikingly, either substrate binding or translocation can be blocked by cross-linking the X-loop to coupling helix 2 or 1, respectively....

Wet snow avalanches in India are common during the mid- and late winter in the Pir Panjal Range (2000–3000ma.s.l.) and during the late winter in the Great Himalayan Range (3000 ma.s.l. and above). Although it is well known that the presence of liquid water in snow makes the flow behaviour of wet snow avalanches different from that of dry snow avalanches, there exist few actual flow measurements with wet snow. The aim of this investigation is to understand the dynamics of wet snow avalanches by conducting medium-scale experiments (volumes of 3, 6 and 11 m3) on the Dhundi snow chute in Himachal Pradesh, India. We measured flow velocities using video data, as well as optical velocity sensors installed on the side walls and running surface. Measurement results relating to the slip velocity of the front and tail of the moving snow mass, as well as the average slip velocity, are presented. In addition, we use the results of the vertical velocity profile measurements to calculate the effec...