This paper considers the explicit solutions of free-edge stresses near circumferential cracks in surface coatings of circular torsion bars and their application in determining the progressive cracking density in the coating layers. The problem was formulated within the framework of linear elastic fracture mechanics (LEFM). The free-edge stresses near crack tip and the shear stresses in the cros...

Tar removal from biomass gasification gas is a crucial problem in applying syngas from biomass for its downstream applications. Catalytic biomass gasification has given promising results for tar cracking. A few research groups have investigated the use of olivine for tar cracking [2,3,4,7,8,9,10]. The presence of oxides of iron and magnesium in the mineral olivine give it the ability to crack h...

The relation of habitual knuckle cracking to osteoarthrosis with functional impairment of the hand has long been considered an old wives' tale without experimental support. The mechanical sequelae of knuckle cracking have been shown to produce the rapid release of energy in the form of sudden vibratory energy, much like the forces responsible for the destruction of hydraulic blades and ship pro...

Forced convective condensation in vertical channel is investigated numerically. The condensation boundary layers that occur due to temperature difference between the walls and saturation temperature of steam is simulated by the volume of fluid (VOF) method. The effect of variations in the hydraulic diameter, steam velocity, Re number and temperature difference between the wall and saturation te...

This paper presents entropy generation minimisation model of combined heat and power system. The turbine control valves and heater throttle valves were analysed. The high-pressure control valves regulate the mass flow rate of steam into the turbine, whereas the intermediate-pressure and lowpressure control valves the steam pressure of the turbine extracts 3 and 5. The steam of the turbine extra...

Activated carbon fibers (ACFs) were prepared by steam activation of windmill palm (WP) (Trachycarpus fortunei) fibers in a nitrogen atmosphere at various temperatures in the 600 to 850 °C range, and their characteristics were investigated. The effects of temperature, in terms of porous texture and surface chemistry, were identified through the use of scanning electron microscopy (SEM), nitrogen...

Highly ordered hexagonal mesoporous aluminosilicates (MAS-5) with uniform pore sizes have been successfully synthesized from assembly of preformed aluminosilcate precursors with cetyltrimethylammonium bromide (CTAB) surfactant. The aluminosilicate precursors were obtained by heating, at 100--140 degrees C for 2--10 h, aluminasilica gels at the Al(2)O(3)/SiO(2)/TEAOH/H(2)O molar ratios of 1.0/7....

the biqian-10 block, located in henan oilfield of sinopic, contains many thin and interbedded reservoirs, which have been operated by cyclic steam stimulation for 20 years or more. therefore, it is a challenge to implement the conventional steam flooding. in order to improve the recovery of steam flooding, urea was used to assist steam flooding. urea can decompose into co2 and nh3, which are be...