Azimuthal angle correlations for rapidity separated Hadron pairs in d+Au collisions at square root of sNN=200 GeV

Deuteron-gold (d+Au) collisions at the Relativistic Heavy Ion Collider provide ideal platforms for testing QCD theories in dense nuclear matter at high energy. In particular, models suggesting strong saturation effects for partons carrying small nucleon momentum fraction (x) predict modifications to jet production at forward rapidity (deuteron-going direction) in d+Au collisions. We report on two-particle azimuthal angle correlations between charged hadrons at forward/backward (deuteron/gold going direction) rapidity and charged hadrons at midrapidity in d+Au and p+p collisions at square root of sNN=200 GeV. Jet structures observed in the correlations are quantified in terms of the conditional yield and angular width of away-side partners. The kinematic region studied here samples partons in the gold nucleus with x~0.1 to ~0.01. Within this range, we find no x dependence of the jet structure in d+Au collisions.     

Random Databases with Approximate Record Matching

In many database applications in telecommunication, environmental and health sciences, bioinformatics, physics, and econometrics, real-world data are uncertain and subjected to errors. These data are processed, transmitted and stored in large databases. We consider stochastic modelling for databases with uncertain data and for some basic database operations (for example, join, selection) with exact and approximate matching. Approximate join is used for merging or data deduplication in large databases. Distribution and mean of the join sizes are studied for random databases. A random database is treated as a table with independent random records with a common distribution (or a set of random tables). These results can be used for integration of information from different databases, multiple join optimization, and various probabilistic algorithms for structured random data.     

An implicit approach to predict the dynamics of granular media

The objective of this study is to present an implicit method to predict the dynamics of granular particles. In the proposed methodology, the dynamics equation of colliding particles are solved implicitly which means the positions of particles at the next time step are also used to compute the next state of the particles. This is in contrast with the explicit approach where only known i.e. past information is used to calculate the new positions. The method is tested in a simple setting where a spherical particle is in continuous movement between two boundary walls. The results show that considerably larger time steps are enabled with the implicit method compared to the explicit method. Future work will compare the overall efficiency of the implicit and explicit methods in more detail. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Perpendicular giant magnetoresistance of magnetic multilayers

The theoretical and experimental studies of the giant magnetoresistance effect in metallic magnetic multilayers with measuring current perpendicular to the interface planes are reviewed. Theoretical formalisms of electronic transport in the inhomogeneous electron gas are critically compared with emphasis on the perpendicular magnetoresistance in multilayers. The effects of interface roughness, potential steps at the interfaces, and realistic band structures are addressed. The experimental determination of the perpendicular resistance of metallic multilayers requires either low-resistance measurement techniques or microfabricated samples with enhanced resistances. The experimental methods known at present are discussed and, where possible, compared with each other.     

Hydrostatic high pressure applied to food sterilization III: Application to spices and spice mixtures

Abstract

The response of suspensions of spices and spice mixtures in water to high pressure treatment was investigated. Inactivation of the microbial load–mainly aerobic and unaerobic spore formers–was strongly dependent on water activity and temperature. Samples were completely decontaminated after three pressure cycles (30 min at 80 MPa followed by 30 min at 350 MPa) at 70 °C at a minimum water activity of 0.91. Pressure treated samples were examined for sensory and chemical changes. No significant changes in odour and appearance were recognized by a trained sensory panel, nor were changes in the volatile compounds of the samples detected by static headspace gaschromatography.     

Helium migration in palladium I. Concentration dependence of helium release

Abstract

High temperature gas release from helium-implanted palladium has been investigated for He/Pd atom fractions from 5 × 10^?6 to 5 × 10^?2. The temperature required for 25 per cent He release increases with increasing dose to an atom fraction of 10^?4, where a sudden reversal occurs for higher concentrations. The release is associated with dramatic changes in the surface features of the palladium. A qualitative physical model is presented to explain the data.     

Helium migration in palladium II. scanning electron microscopy examination of high concentration samples

Scanning electron microscopy has been used to examine bulk phenomena of palladium samples annealed at 1200°C after implantation to a dose of 10¹⁷ He atoms/cm² at 5 MeV. A 3μ deep porous layer was found at a depth of 10.9μ±0.3μ. Wide grain boundaries (microcracks) extended from this layer to the top surface of the sample.     

Triple resonance investigation of F centres in BaFCl

Abstract

In BaFCl two types of F centres can be produced, where the electron occupies a Cl^? vacancy [F(Cl^?)-centres] or an F^? vacancy [F(F^?)-centres]. When producing F(F^?)-centres the simultaneous production of F(Cl^?)-centres cannot be avoided. Both ESR spectra overlap strongly. The ENDOR spectra contain very many lines of both centres and have a very complicated angular dependence. It is shown that the angular dependence of the ENDOR spectra of both F centres can be measured separately by applying a double ENDOR technique (called also Triple Resonance). The ratio of the signal heights of the ENDOR lines compared to the double ENDOR lines is characteristic for the neighbour shell to which the nuclei involved belong. The use of this effect for the analysis of the spectra and its explanation are discussed.     

Ion beam mixing induced by electronic energy deposition in Fe-Si multilayers

Abstract

Spectroscopic properties of Ce³⁺ ions in GdAlO₃ crystal are presented. At least three Ce³⁺ nonequivalent centres (multisites) are present in this crystal. Energy transfer from the Ce³⁺ main in the UV emitting centres to the Ce³⁺ green emitting centres is observed. Ce³⁺ fluorescence decays are either fast (1.5–20 ns) or slower due to complicated processes of energy transfer and migration (Ce³⁺)_i → (Gd³⁺)_n-steps → (Ce³⁺)_j (energy transfer through Gd³⁺ sublattice).