Chromate uptake characteristics of the pristine layered double hydroxides of Mg with Al

The layered double hydroxides (LDHs) of Mg with Al readily scavenge dissolved chromate ions under a wide range of conditions. While the chromate uptake is quantitative in the LDH containing 33 mol% Al, the uptake is only 58% of the stoichiometric value in the LDH containing 25 mol% Al. This indicates that the lower symmetry of the NO3− ions in the LDH with 33 mol% Al facilitates the intercalation of chromate ions even under conditions of equilibration with excess dissolved nitrate ions. The chromate uptake obeys the Langmuir adsorption isotherm suggesting that the entire interlayer region of the LDH behaves like a surface. This surface is structural rather than morphological as the chromate uptake correlates negatively with the BET surface area of the LDHs

Micorwave Energy Aided Mineral Comminution

Mineral liberation during beneficiation is essentially through comminution. However, the fact that the major slice (up to 50 percent) in the pie for total energy requirements during beneficiation is occupied by comminution, dictates us to look into various possi-bilities to render comminution more energy-efficient. In the early 1900s, efforts for reduction in the crushing and grinding energies based on the concept, 'thermally assisted liberation' (T A L) were made but could not be commercially exploited. With the advent of microwave energy and applications in different commercial operat-ions based on its property of heat generation in materials encouraged it in utilizing as an aid during comminution. Microwave energy heats individual phases in an ore matrix to different heat levels as per individual microwave absorption characteristics. Exposure to microwave energy over discrete time intervals prior to comminution results in development of micro fractures due to differential heating. Weakening of interspatial bonding in the ore matrix helps in lesser energy requirements. Numerous studies on microwave energy applications in the field of mineral processing and extractive metallurgy are under-taken in many parts of the world in recent years

Imaging the dust sublimation front of a circumbinary disk

We present the first near-IR milli-arcsecond-scale image of a post-AGB binary that is surrounded by hot circumbinary dust. A very rich interferometric data set in six spectral channels was acquired of IRAS08544-4431 with the new RAPID camera on the PIONIER beam combiner at the Very Large Telescope Interferometer (VLTI). A broadband image in the \textit{H} band was reconstructed by combining the data of all spectral channels using the SPARCO method. We spatially separate all the building blocks of the IRAS08544-4431 system in our milliarcsecond-resolution image. Our dissection reveals a dust sublimation front that is strikingly similar to that expected in early-stage protoplanetary disks, as well as an unexpected flux signal of $\sim$4\% from the secondary star. The energy output from this companion indicates the presence of a compact circum-companion accretion disk, which is likely the origin of the fast outflow detected in H$\alpha$. Our image provides the most detailed view into the heart of a dusty circumstellar disk to date. Our results demonstrate that binary evolution processes and circumstellar disk evolution can be studied in detail in space and over time.Comment: PR @ http://www.eso.org/public/news/eso1608

On the performance of stabilized α-nickel hydroxide as a nickel-positive electrode in alkaline storage batteries

The internal resistance of a stabilized α-nickel hydroxide electrode is found to be lower than that of a β-nickel hydroxide electrode as shown from studies of the open-circuit potential-time transients at all states-of-charge. Nevertheless, the self-discharge rates of the former is higher. Gasometric studies reveal that the charging efficiency of the α-nickel hydroxide electrode is higher than that of the β-nickel hydroxide electrode. © 1995

Explicit MBR All-Symbol Locality Codes

Node failures are inevitable in distributed storage systems (DSS). To enable efficient repair when faced with such failures, two main techniques are known: Regenerating codes, i.e., codes that minimize the total repair bandwidth; and codes with locality, which minimize the number of nodes participating in the repair process. This paper focuses on regenerating codes with locality, using pre-coding based on Gabidulin codes, and presents constructions that utilize minimum bandwidth regenerating (MBR) local codes. The constructions achieve maximum resilience (i.e., optimal minimum distance) and have maximum capacity (i.e., maximum rate). Finally, the same pre-coding mechanism can be combined with a subclass of fractional-repetition codes to enable maximum resilience and repair-by-transfer simultaneously

The usefulness of confusion, urea, respiratory rate, and shock index or adjusted shock index criteria in predicting combined mortality and/or ICU admission compared to CURB-65 in community-acquired pneumonia

Peer reviewedPublisher PD

Observation of direct and indirect magnetoelectricity in lead free ferroelectric (Na 0.5Bi 0.5TiO 3)-magnetostrictive (CoFe 2O 4) particulate composite

A particulate composite consisting of 65 mol. % Na 0.5Bi 0.5TiO 3 and 35 mol. % CoFe 2O 4 was synthesized, and it's structure, microstructure, ferroelectric, magnetostrictive, magnetic, and direct/indirect magnetoelectric properties were studied. The composite showed different magnetization behaviour under electrically poled and un-poled conditions. The percentage change in magnetization as a result of poling is approximately -15% at 500 Oe magnetic field. Magnetostriction measurements displayed a value of λ 11 = -57 × 10 -6 and piezomagnetic coefficient δλ 11/δH = 0.022 × 10 -6 kOe -1 at 2.2 kOe for the composite. The maximum magnetoelectric output varied from 1350 mV/cm to 2000 mV/cm with change in the electrical poling condition

Uncertainties in stellar evolution models: convective overshoot

In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties remain due to our poor knowledge of some complex physical processes that require an empirical calibration, such as the efficiency of the interior mixing related to convective overshoot. Here we review the impact of convective overshoot on the evolution of stars during the main Hydrogen and Helium burning phases.Comment: Proc. of the workshop "Asteroseismology of stellar populations in the Milky Way" (Sesto, 22-26 July 2013), Astrophysics and Space Science Proceedings, (eds. A. Miglio, L. Girardi, P. Eggenberger, J. Montalban

Electrochemically Impregnated Aluminum-Stabilized α-Nickel Hydroxide Electrodes

Nickel-positive electrodes obtained by electrochemical impregnation of aluminum-substituted α-nickel hydroxide are found to deliver a reversible discharge capacity of ca. 450 mAh/g. This is much higher than the capacity of β-nickel hydroxide electrodes 200 mAh/g: this work; 225 mAh/g: Dixit et al., J. Power Sources, 63, 167 (1996) prepared under identical conditions and pasted electrodes comprising cobalt-doped nickel hydroxide 345 mAh/g: Faure et al., J. Power Sources, 36, 497 (1991). These observations suggest that the theoretical target-capacity for high-performance nickel-positive electrodes must be revised from the currently accepted value of 289 mAh/g (1e exchange) to 491 mAh/g 1.7e exchange: Corrigan and Knight, J. Electrochem. Soc., 136, 613 (1989). © 1999 The Electrochemical Society. S1099-0062(98)08-044-4. All rights reserved