Efficiency and optimisation of fin with temperature-dependent thermal conductivity: a simplified solution

An analytical simplified solution is proposed for temperature distribution and fin efficiency, when thermal conductivity is temperature dependent. An optimal linearization technique is used to solve the nonlinear equation. Based on classical solution, some accurate results are obtained and presented with thermal conductivity parameter and fin parameter. Arithmetic mean temperature is less precise than an equivalent thermal conductivity. Optimal thickness for rectangular fin is derived.     

Behavior Study of ZnO Thin Films Grown by PLD for Several Applications

Crystallography Reports - In this work, the effects of glass and Si polycrystalline substrates on structural, morphological, optical and electrical properties of zinc oxide thin films (ZnO)...     

Adsorption of strontium (II) ions from aqueous solution onto bottom ash of expired drug incineration

Journal of Radioanalytical and Nuclear Chemistry - Bottom Ash of Expired Drug Incineration (BAEDI) is used in this study for the removal of Sr(II). In the kinetic study, the experimental results...     

Semi-empirical correlation of solid solute solubility in supercritical carbon dioxide: Comparative study and proposition of a novel density-based model

A comprehensive data set on experimental solubility of 210 solid solutes in supercritical CO₂ counting 5550 data points has been used for comparison of the correlation performance of 21 empirical models. On the basis of the comparison results a new eight-parameter density-based model has been proposed. The comparison shows that the three-parameter models are the least accurate. The results also show that models that relate the logarithm of the solubility to the logarithm of solvent density and temperature are more accurate than models that include the pressure. When comparing the overall correlating performance in terms of average absolute relative deviation the proposed model is by far the best with an average absolute relative deviation lying in the range 0.17–81.99% and an average value of 8.88%.     

Biosorption of strontium from aqueous solutions onto spent coffee grounds

A set of experiments was carried out to evaluate the strontium uptake potential of spent coffee grounds (SCG) by batch tests in aqueous medium. Adsorption of Sr²⁺ as a function of contact time and adsorbent dose, pH, particles size, agitation speed, temperature and co-ions presence was investigated. Obtained results revealed that the maximum adsorption took place at pH range of 5–8 and temperature values between 283 and 333 K. Particles size effect was not very significant and agitation speed influenced on the equilibrium time. Competitive adsorption experiments allowed us to classify the negative effect on the Sr²⁺ uptake according to this order Al³⁺ ? Co²⁺ > Mg²⁺ > Ca²⁺ ? Na⁺ > K⁺ > Cs⁺. Kinetic study indicated that the Sr²⁺ uptake was fast and it was well fitted by the pseudo second order reaction model. Adsorption isotherm was well interpreted by Langmuir model. The maximum adsorption capacity was found to be 69.01 mg g^?1 at pH 7, 293 K, particles sizes = 200–400 μm and agitation speed 250 rpm. The thermodynamic study revealed that the process was spontaneous (ΔG ⁰ < 0), exothermic (ΔH ⁰ < 0) with a raised affinity for Sr²⁺ (ΔG ⁰ < 0, ΔS ⁰ > 0) and occurred by physical adsorption (E _a = 8.37 kJ mol^?1). FTIR analysis showed carboxylic acid and amino group presence on SCG surface playing a vital role in Sr²⁺ biosorption.