after springs production, different residual stresses are created in the inner and outer surfaces of spring wires. some of these stresses for example compressive residual stresses are useful and some are harmful. the effects of vareation of these stresses are caused spring relaxation and decrising in their free length when they are loaded intermittently. for review this phenomena in this resear...

abstract: minimizing the work consumed in refrigeration system is the most effective measure to reduce the cost of products in sub-ambient chemical processes. the introduction of mixed working fluids into refrigeration system in place of pure working fluids is a recent advancement applied in the field. due to the lack of systematic design method for mixed refrigerant cycle (mrc), conventional a...

in this study, bio-based carbon nanotubes (cnts) have received considerable research attention due to their comparative advantages of high level stability, simplistic use, low toxicity and overall environmental friendliness. new potentials for improvement in heat transfer applications are presented due to their high aspect ratio, high thermal conductivity and special surface area. phonons have ...

in order to establish the appropriate methane fermentation technology for low strength wastewater, a 2.0 l egsb reactor was operated at 20â°c with 0.3 - 0.4 g cod/l of sucrose-based synthetic wastewater for 500 days. at the start up period, the reactor was operated in egsb mode with a 5 m/h up flow velocity by continuous effluent recirculation. however, the egsb reactor exhibited insufficient c...

effect of small al additions, from 0.14% to 0.31% ai, on the hot deformation behavior of low carbon steels containing 1%cu-1.2%mn was investigated in the temperature range of 750-800•c over the strain rate range of 1o.3.1o.1s•1 by a hot compression testing machine. the flow curves obtained, exhibited typical characteristics of dynamic recovery type of softening mechanism, and the critical strai...

the aim of this study was to evaluate the effects of balancing low protein diets for methionine and lysine on performance of early lactation holstein cows under hot environmental temperature. twenty one multiparous holstein cows in early lactation were allocated to three experimental rations including, 1) high protein ration with 17.5% cp, 2) medium protein ration with 16% cp and 12 g/d rumen p...

large amounts of hydrocarbon reserves are trapped in naturally fractured reservoirs which arechallenging in terms of accurate recovery prediction because of their joint fabric complexity andlithological heterogeneity. canada, for example, has over 400 billion barrels of crude oil in fracturedcarbonates in alberta, most of this being bitumen of viscosity greater than 106 cp in the grosmontformat...

The persistence of shear stress fluctuations in viscous liquids is a direct consequence of the non-zero shear stress of the local potential minima which couples stress relaxation to transitions between inherent structures. In simulations of 2D and 3D glass forming mixtures, we calculate the distribution of this inherent shear stress and demonstrate that the variance is independent of temperatur...

strain induced precipitation in hsla-100 steel was investigated by conducting hotcompression and relaxation tests at temperature range of 850°c to 1100°c and strain rate of 0.001s-1 to 1s-1. the absence of dynamic recrystallization at temperatures below 1000°c was attributedto the influence of dynamic precipitation. the stress relaxation tests showed that strain inducedprecipitation is possible...

compound of 5-aminolevulinic acid (5-ala) has herbicide behavior in high concentration. while, it acts as growth regulator at low concentrations and causes resistance to various stresses incluing cold and salibity. therefore the exogenous application of 5-aminolevulinic acid was investigated to induce cold stress tolerance in young soybean plants (glycine max l.). the experiment was conducted a...