Magnetic and transport properties of Laves phase Dy1−xMmxCo2 (x = 0–0.5) alloys

The influence of Mm substitution (Mm = mischmetal) on structural, transport and magnetic properties of (Dy_1?xMm_x)Co₂ (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) alloys has been investigated by means of X-ray diffraction (XRD), temperature dependent electrical resistivity (ρ(T)), ac susceptibility (χ(T)) and thermopower (S(T)). XRD patterns show the formation of solid solutions crystallizing with cubic Laves (C15) type structure at room temperature. The pronounced discontinuities in the resistivity and thermopower at Curie temperature (T_C) are explained based on the suppression of the spin-fluctuation contribution. The gradual decrease in T_C and sharpness of discontinuities in ρ(T) and S(T) with increasing Mm substitution has been discussed.     

Peristaltic transport in an asymmetric channel with heat transfer — A note

The problem of heat transfer for the motion of a viscous incompressible fluid induced by travelling sinusoidal waves has been analytically investigated for a two-dimensional asymmetrical channel. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The flow is investigated in a wave frame of reference moving with the velocity of the wave. The momentum and energy equations have been linearized under long-wavelength and low-Reynolds number assumptions and closed form expressions for temperature and coefficient of heat transfer have been derived. The effect of Hartmann number, Eckert number, width of the channel and phase angle on temperature and coefficient of heat transfer are discussed numerically and explained graphically.     

An Efficient,Stable and Reusable Palladium Nanocatalyst: Chemoselective Reduction of Aldehydes with Molecular Hydrogen in Water

Palladium nanoparticles (Pd‐BNP) stabilized by a binaphthyl‐backbone can be efficiently used for the chemoselective reduction of aldehydes in the presence of hydrogen at room temperature in water. The Pd‐BNP catalyst is easily recovered and reused for five catalytic cycles.

     

Factors affecting the puffing quality of paddy

Histological studies showed that in good puffing varieties of paddy the aleurone layer was thin and weak at the specific points of bursting while the clearance between the husk and kernel was large and the grain was easily shelled. In the poor puffing varieties the aleurone was uniformly thicker along the peripheral section while clearance between husk and grain was smaller and the grains were relatively more difficult to shell. Optimum maturity of grains at an average grain moisture of 20 to 24% was essential for getting maximum puffing. Delayed harvesting caused sun checks and reduced overall puffing expansion. Sun checks caused by severe drying in the sun produced a similar effect. High grain density was associated with better puffing.     

Impact of information sharing in hierarchical decision-making framework in manufacturing supply chains

This paper presents a comprehensive framework for the analysis of the impact of information sharing in hierarchical decision-making in manufacturing supply chains. In this framework, the process plan selection and real-time resource allocation problems are formulated as hierarchical optimization problems, where problems at each level in the hierarchy are solved by separate multi-objective genetic algorithms. The considered multi-objective genetic algorithms generate near optimal solutions for NP-hard problems with less computational complexity. In this work, a four-level hierarchical decision structure is considered, where the decision levels are defined as enterprise level, shop level, cell level, and equipment level. Using this framework, the sources of information affecting the achievement of best possible decisions are then identified at each of these levels, and the extent of their effects from sharing them are analyzed in terms of the axis, degree and the content of information. The generality and validity of the proposed approach have been successfully tested for diverse manufacturing systems generated from a designed experiment.     

Kinetics of emitted mass—A study with three dry powder inhaler devices

The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min⁻¹) from three dry powder inhaler devices, Rotahaler^® (RH), Monodose Inhaler^® (MI) and Handihaler^® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (k_CCEM), estimated from a modelling approach, increased with increasing air flow rates. The k_CCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The k_CCEM was highest from RH and lowest from MI. Differences in k_CCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers.     

Structure and phase stability of hydrogenated first-stage alkali- and alkaline-earth metal–graphite intercalation compounds

We report the hydrogenation temperature and pressure dependence of hydrogen absorption capacity in CaC₆. In addition, the structure and phase stability of hydrogenated CaC₆, LiC₆ and KC₈ has been investigated using X-ray diffraction and Raman spectroscopy. It is found that the hydrogen chemisorption in both CaC₆ and LiC₆ leads to either metastable or higher stage intermediate compounds but eventually leaves completely deintercalated graphite by forming stable metal hydrides. In contrast hydrogenation of KC₈ generates a restaged ternary hydride compound. The phase stability of hydrogenated compounds is discussed in the text based on the observed experimental results and correlated to the thermodynamic and kinetic aspects of intercalated metal.