Effect of Particle Size Distribution on the Performance of a Catalytic Fluidized Bed Reactor

Computational Fluid Dynamics (CFD) has been used to model ozone decomposition in a two-dimensional fluidized bed of 2.0 meters height and 0.1 m width. Simulations were carried out with mono-size, bimodal, and wide catalyst particle size distributions with the same mean diameter to model the effect of fines on the reaction. CFD predictions fall within 20% of the experimental data

A Vertical Resonance Heating Model for X- or Peanut-Shaped Galactic Bulges

We explore a second order Hamiltonian vertical resonance model for X-shaped or peanut-shaped galactic bulges. The X-shape is caused by the 2:1 vertical Lindblad resonance with the bar, with two vertical oscillation periods per orbital period in the bar frame. We examine N-body simulations and find that due to the bar slowing down and disk thickening during bar buckling, the resonance and associated peanut-shape moves outward. The peanut-shape is consistent with the location of the vertical resonance, independent of whether the bar buckled or not. We estimate the resonance width from the potential m=4 Fourier component and find that the resonance is narrow, affecting orbits over a narrow range in the angular momentum distribution, dL/L ~ 0.05. As the resonance moves outward, stars originally in the mid plane are forced out of the mid plane into orbits just within the resonance separatrix. The height of the separatrix orbits, estimated from the Hamiltonian model, is approximately consistent with the peanut-shape height. The X-shape is comprised of stars in the vicinity of the resonance separatrix. The velocity distributions from the simulations illustrate that low inclination orbits are depleted within resonance. Within resonance, the vertical velocity distribution is broad, consistent with resonant heating caused by the passage of the resonance through the disk. In the Milky Way bulge we relate the azimuthally averaged mid-plane mass density near the vertical resonance to the rotation curve and bar pattern speed. At an estimated vertical resonance galactocentric radius of ~1.3 kpc, we confirm a mid-plane density of ~5x10^8 Msol/kpc^3, consistent with recently estimated mass distributions. We find that the rotation curve, bar pattern speed, 2:1 vertical resonance location, X-shape tips, and mid-plane mass density, are all self-consistent in the Milky Way galaxy bulge.Comment: accepted for publication in MNRA

Analysis of inappropriate medication use and drug interaction in older people visiting tertiary care center of eastern Nepal

Background: Medication use in older people has been increasing as the incidence of chronic diseases increases worldwide. Use of more medicines may increase the chance of prescribing potentially inappropriate medications (PIMs) and may increases the risk of potential drug-drug interactions (pDDIs). The objective of this study was to assess PIMs and pDDIs to improve the rational use of medicationsMethods: In this study data from the older people were obtained from patient visiting medicine, OPD, BPKIHS, Dharan. Demographic and medications information were collected. PIM and pDDIs were evaluated from medication data using the Beer’s criteria for potentially inappropriate medication use in older adults, 2015 and lexicomp application respectively.Results: Among 550 patients 50.9% patients were male. Common diagnosis was systemic hypertension 335 (64.5%) followed by type 2 diabetes mellitus 276 (50.18%). The most commonly prescribed drug was metformin (215) followed by amlodipine (205), atorvastatin (176), losartan (158), glimepiride (113) and aspirin (100). One or more fixed drug combination was present in 295 prescriptions. One or more PIM were present in 29 (5.3%) prescriptions. Commonly prescribed PIM was prazosin (11) followed by nitrofurantoin (5). There were total of 753 cases of pDDIs, with 116 (15.40%) cases of risk categories X and D.Conclusions: Our findings demonstrated PIM use were relatively less. However, pDDIs were common in older people suggesting that optimal medication use and further similar studies in larger scale are necessary in this population