Oxidative coupling of methane and dehydroaromatization are attractive one-step conversion routes to make valuable platform chemicals more sustainable. Both processes require elevated temperatures above 600°C, good heat management, the use heterogeneous catalysts. None these reactions yet commercial due many technical challenges. This work explores potential combining two under one umbrella over...

In this work, the mathematical modelling of peristaltic transport for incompressible Sutterby fluid through cavity between coaxial tubes where inner tube is fixed and outer has sinusoidal rhythmic fluctuations along channel’s walls presented. Under assumption long wavelength low Reynolds number, governing equations (motion, temperature, concentration) are illustrated in cylindrical coordinates....

Abstract We prove that a flow of cold collisionless particles from all directions in and out of a region necessarily forms a caustic. A corollary is that, in cold dark matter cosmology, galactic halos have inner caustics in addition to the more obvious outer caustics. The outer caustics are fold catastrophes located on topological spheres surrounding the galaxy. To obtain the catastrophe struct...

Abstract—Rotary draw bending is a method which is being used in tube forming. In the tube bending process, the neutral axis moves towards the inner arc and the wall thickness distribution changes for tube’s cross section. Thinning takes place in the outer arc of the tube (extrados) due to the stretching of the material, whereas thickening occurs in the inner arc of the tube (intrados) due to th...

The heat generated in a high-temperature gas-cooled reactor can be used to drive the iodine-sulfur cycle produce hydrogen. However, sulfuric acid decomposition step requires sophisticated decomposer increase rate. of mainly occurs catalytic zone, and optimization its structure is very important for increasing This study focuses on structural design zone unit. with double inner tubes designed an...

field ion microscopy (fim) and scanning tunneling microscopy (stm) have found a wide application in nanotechnology. these microscopes use a metallic nanotip for image acquisition. resolution of fim and stm images depends largely on the radius of nanotip apex; the smaller the radius the higher the resolution. in this research, for tungsten nanotip fabrication, electrochemical etching of tungsten...

HYPOTHESIS Albuterol delivery through a tracheostomy tube is affected by device (nebulizer vs metered-dose inhaler), interface (mask vs T-piece), bias flow, and humidification. METHODS A lift bar was placed between the chambers of a dual-chambered lung model such that a ventilator triggered simulated spontaneous breathing at a rate of 20 breaths/min, tidal volume of 0.4 L, and inspiratory-exp...

The pressure drop of refrigerant R-134a flow boiling inside a horizontal tube has been investigated experimentally. The test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. These instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. This system consisted of three electrically heated evapor...

in this study, fluid flow and energy separation in a micro-scale ranque-hilschvortex tube are numerically investigated. the flow is assumed as 2d, steady,compressible ideal gas, and shear-stress-transport sst k-w is found to be a bestchoice for modeling of turbulence phenomena. the results are in a good agreementwith the experimental results reported in the literature. the results show that flu...

  In this study, fluid flow and energy separation in a micro-scale Ranque-HilschVortex Tube are numerically investigated. The flow is assumed as 2D, steady,compressible ideal gas, and shear-stress-transport SST k-W is found to be a bestchoice for modeling of turbulence phenomena. The results are in a good agreementwith the experimental results reported in the literature. The results show that f...