Numerical Modeling of Heat Transfer for Gas-Solid Flow in Vertical Pipes

A two-fluid model (TFM) based on the kinetic theory was used to study the heat transfer of gas-solid flows in a vertical pneumatic conveyor. A 2-D, vertical pipe with 1.1 m length and 0.017 m internal diameter was chosen as the computation domain. Pipeline has 0.86 m heat transfer section after a 0.28 m developing section. It was found that the voidage has minimum and dimensionless velocities, and temperatures have maximum values in the centerline. A convective heat transfer coefficient decreases along the pipeline, and it was found that the heat transfer coefficient of gas-solid flow is greater than clean gas.     

Optical characterization of electron beam evaporated chloroindium phthalocyanine thin films

In present study, the optical properties of chloroindium phthalocyanine (ClInPc) thin films prepared by electron beam evaporation have been investigated. The optical characteristics of the prepared thin films have been determined using spectrophotometric measurements of the absorbance, transmittance and reflectance at normal incidence in the spectral range 300–1,100 nm. Surface morphology of thin films is studied using field emission scanning electron microscopy. The absorption spectra recorded in UV-Visible region for the deposited films show two well defined intense absorption bands of phthalocyanine molecule; namely the Q-band and the Soret (B-band). The analysis of the spectral behavior of the absorption coefficient in the intrinsic absorption region have been performed to determine the optical band gap energy and type of the electronic transition, which reveals the probability of direct and indirect transitions. Moreover, by studying the absorption coefficient spectra just below the fundamental absorption edge, the width of band tails of localized states (Urbach energy), steepness parameter and width of the defect states have been evaluated. The obtained results of this novel grown ClInPc thin films support the desirable feature for the optoelectronic devices.     

Effects of post-deposition annealing on morphology and optical properties of electron beam evaporated Bromoaluminium phthalocyanine thin films

In this paper, effects of post-deposition annealing on morphology and optical properties of electron beam evaporated Bromoaluminium phthalocyanine thin films have been investigated. Surface morphology of the films have been characterized by field emission scanning electron microscopy (FESEM). The FESEM micrographs have shown densely packed nanoparticles and nanorod-like structures for the films annealed at different temperatures. Conditions leading to β-phase have been identified by monitoring post-deposition annealing using optical absorption spectroscopy (UV–Vis). The optical absorption measurements on the as-deposited and annealed films shows that the absorption mechanism is due to direct transition. Also, it is found that the optical band gap decreases with increase in annealing temperature.     

Investigation of Effects of Toroidal Field Ripple on Plasma Poloidal Beta in IR-T1 Tokamak

We present an investigation of effect of Toroidal Field (TF) ripple (due to finite number of the toroidal field coils) on the plasma poloidal Beta in IR-T1 Tokamak. For this purpose, array of magnetic probes and also a diamagnetic loop with its compensation coil were designed, constructed, and installed on the outer surface of IR-T1. Amplitude of the TF ripple is obtained 0.01, and also the effect of the TF ripple on the poloidal Beta discussed. In the high field side region of tokamak chamber, the TF ripple effect is decreasing of the poloidal Beta, whereas the low field side has inverse situation.     

Collapse behavior evaluation of asymmetric buildings subjected to bi‐directional ground motion

This paper discusses the collapse behavior of low‐rise plan‐asymmetric buildings under bi‐directional horizontal ground motions and utilizing strength and stiffness degrading nonlinear models. For this purpose, three‐dimensional three‐story and six‐story reinforced concrete frame buildings with uni‐directional mass eccentricities equal to 0% (symmetrical), 10%, 20% and 30% are subjected to nonlinear static (pushover) as well as incremental dynamic analyses using a set of far‐field two‐component ground motions and their performance are assessed on the basis of the safety margin against collapse and its probability of occurrence. Comparison of the collapse margin ratios as well as the fragility curves demonstrates significant reduction of the collapse‐level ground motion intensity with increasing eccentricity in plan. Results also indicate that current seismic design parameters including the response modification (R), overstrength (Ω) and ductility (μ) factors are not appropriate for buildings with high levels of plan eccentricity. Buildings with high values of plan eccentricity do not meet the design target life safety performance level on the basis of the calculated probability of collapse and safety margin against collapse. It appears that re‐evaluation of their design parameters is necessary. Copyright © 2015 John Wiley & Sons, Ltd.     

Analytische Betrachtung der Bruchmechanismen in AlSiCu‐Gusslegierungen

In this work the fracture toughness and responsible microstructural characteristics of AlSiCu casting alloys were investigated. A conventional A226 alloy and an alloy which is adapted for high temperature use were analyzed. A strong relationship between the cooling speed and the mechanical properties was found as well as the phases responsible for failure were identified.     

HEEC: a hybrid unequal energy efficient clustering for wireless sensor networks

Wireless Networks - An important challenge in wireless sensor networks is energy conservation. Recently, several hybrid, dynamic and static clustering protocols have been proposed to solve this...     

Astute,fine and fast method of iris segmentation in unlimited circumstances

Neural Computing and Applications - Currently, Iris detection is considered as a significant module for robust biometric systems and high-speed applications such as eye tracking. Most iris...