Home > Archives > Latest issue
International Review of Chemical Engineering (Rapid Communications) - September 2012 (Vol. 4 N. 5) - Papers
Open Door Initiative (ODI) (3rd edition)
| |
International Review of Chemical Engineering (Rapid Communications) - Papers
Using
a Marine Biomass for the Treatment of Wastewaters Containing U and Th:
The Kinetics and Equilibrium of Biosorption
by Antonio C. A.
da Costa, Antonia C. da Silva, Ana C. M. Ferreira
Vol. 4. n. 5, pp. 440-449
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Uranium, Thorium, Biosorption, Kinetics, Equilibrium, Sargassum Filipendula.
Long-Term
Hydration of Dicalcium Silicates
by Mariane Silva
de Miranda, Flávio Aparecido Rodrigues
Vol. 4. n. 5, pp. 450-454
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Dicalcium Silicate, Cement, Hydration.
Thermodynamic
Modeling of PES/CA Blend Membrane Preparation
by H. Abdallah, S.
S. Ali
Vol. 4. n. 5, pp. 455-465
Abstract - Thermodynamic behavior of quaternary system with one low molecular weight component; N –Methylpyrrolidone (NMP) as a solvent, non-solvent; polyethylene glycol (PEG 400) and two high molecular weight polymers; polyethersulfone (PES) and cellulose acetate (CA) was investigated. An extended modified Flory-Huggins model was used. The predicted results from model of critical temperature for superiority properties of polymer blend solution were in range between UCST 323 K and LCST 350 K. However, the increasing the vaporization time of PES/CA blend membrane to 30 min has increased the heat of vaporization to 133659.6 J/mole which led to increase in cohesive energy density to 1311.82 J/cm3 and gained more solvent evaporation. The diffusion model was studied on the immersion precipitation process which was indicated that solvent and non-solvent volume fractions increased with time in the coagulation bath , while the polymer solution volume fraction decreased due to solvent and non-solvent removal from polymer solution and blend membrane formation. The predicted results from model of heat treatment process on blend membrane were indicated that increasing in membrane thickness and formation of dense layer in blend membrane.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Thermodynamic Behavior, Quaternary System, Immersion Precipitation, Heat Treatment.
Thermodynamic Analysis of Ethanol Dehydration to Ethylene through Equilibrium
Constant Method Using Classic Thermodynamics and Quantum Chemistry
by Alice M. de
Lima, Adilson J. de Assis, Carla E. Hori, Miria H. E. Reis, Antonio E. H.
Machado
Vol. 4. n. 5, pp. 466-473
Abstract - In the last decades, ethylene production from ethanol was not largely investigated mainly because of the viability and low costs of natural gas and naphtha. Nowadays, ethylene production is usually done by cracking of hydrocarbons. However, the manufacture of ethylene from ethanol is getting more attention mostly due to environmental reasons. The objective of this paper is to compare the equilibrium conversions and compositions of reactions systems involved in ethylene production from ethanol through computational simulations. The obtained results can help to find better operational conditions and elucidate preferential reaction routes involved in ethanol dehydration.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Chemical Equilibrium, Ethanol Dehydration, Molecular Modeling.
Optimization of HPMC and Water Addition For a Gluten-Free Formula with
Rice and Field Bean Based on Rheological Properties of Doughs
by Le. Benatallah,
M. N. Zidoune, C. Michon
Vol. 4. n. 5, pp. 474-481
Abstract - Formulation and manufacture of gluten-free bread with rice and field bean were investigated. A 5-level Central Composite Design with two factors – hydroxypropylmethyl cellulose (HPMC) and water - was elaborated. Cereal dough samples composed of 2/1 (w/w) rice/field bean were made. Results were compared to a control of soft wheat. Rheological properties of dough (storage modulus, loss angle, stiffness, stress-hardening and relaxation index) were evaluated. A selection of two HPMC – water concentration domains were found using rheological values matching those of wheat flour dough. Within these two domains, rheological parameters and bread making tests were realized in order to confirm the validity. The level of HPMC-water which displays a specific volume closest to the control was [3.32-90.5]%. Loss angle, measured at 60°C, was inversely related to the fineness of breadcrumb as was the case for wheat dough. Crumb fineness increases with the specific volume of bread. No correlation was observed between crumb heterogeneity and stress-hardening character of gluten-free breads measured at different biaxial extension rates. Moreover a more marked stress-hardening character measured at 38°C and at low biaxial extension rate seems to lead to bread with small specific volume.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Formulation, Gluten-Free Doughs, Rice, Field Bean, Specific Volume, Rheological Properties, Alveolar Structure.
Effect
of Temperature on Continuous Production of Sulfur and Formaldehyde
Coated Urea
by M. H.
Ismayanda, A. Muslim
Vol. 4. n. 5, pp. 482-486
Abstract - An immersing and spray coating process has been developed for the continuous production of sulfur coated urea (SCU) and formaldehyde coated urea (FCU) in a fluidized bed. The coated urea was produced in a laboratory scale unit with the coating temperature of 30, 50 and 70oC. The SCU and FCU dissolution rates were studied and performed in a stirred tank. The effect of coating temperature was investigated, and a result showed that the dissolution of SCU and FCU in distilled water decreased with the increase in coating temperature. Referenced models and optimization method were adopted to obtain the SCU and FCU diffusion coefficients, and the experiment based results were in very good agreements with the model based results. As the result, the SCU diffusion coefficient was approximately 1.733E-05, 1.643E-05 and 1.402E-05, and the FCU diffusion coefficient was approximately 2.246E-05, 1.877E-05 and 1.531E-05 for the coating temperatures of 30, 50 and 700C respectively. In addition, the SCU dissolution rate was approximately 0.149, 0.144 and 0.129 g/min, and the FCU dissolution rate was approximately 0.167, 0.152 and 0.132 g/min for the coating temperatures of 30, 50 and 700C respectively. It was obvious that increasing the coat temperature resulted in increasing the diffusion and dissolution of urea, and sulfur was the better coating material than formaldehyde in terms of controlled release of urea.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Urea, Coating, Dissolution, Diffusion, Fluidized Bed, Stirred Tank.
Preface
by Jordan Hristov
Vol. 4. n. 5, pp. 487-488
An Exercise with the He’s Variation Iteration Method To a Fractional
Bernoulli Equation Arising in Transient Conduction with Non-Linear Heat
Flux at the Boundary
by Jordan Hristov
Vol. 4. n. 5, pp. 489-497
Abstract - Surface
temperature evolution of a body subjected to a nonlinear heat flux
involving counteracting convection heating and radiation cooling has
been solved by the variations iteration method (VIM) of He. The surface
temperature equations comes as a combination of the time-fractional
(half-time) subdiffusion model of the heat conduction and the boundary
condition relating the temperature field gradient at the surface through
the Riemann-Liouville fractional integral. The result of this equation
is a Bernoulli-type ordinary fractional equation with a non-linear term
of 4th order. Two approaches in the identification of the general
Lagrange multiplier and a consequent application of VIM have been
applied. The common method replaces the fractional integral (in the
Riemann-Liouville sense) by an integer order integral. The more exact
method of Wu uses an initial Laplace transform of the fractional
integral in the iteration formula to find correctly the Lagrange
multiplier. Both approaches yield different Lagrange multipliers which
results in different numerical results.The article discusses the origin
of these differences in the light of correct application of VIM. The
developed approximate solutions have been used in numerical simulation
showing the effect of Biot number and the radiation-conduction number on
the surface temperature evolution.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Variational Iteration Method, Bernoulli-Like Fractional Equation, Lagrange Multiplier, Surface Temperature Evolution.
A Note on an Improved Variational Iteration Method for Nonlinear
Equations Arising in Heat Transfer
by Fazhan Geng
Vol. 4. n. 5, pp.
498-500
Abstract - An
improved variational iteration method for solving nonlinear equations
arising in heat transfer is conceived. The main advantage of the present
method is that it can enlarge the convergence region of iterative
approximate solutions. Also, the present method can be used to solve
strong nonlinear problems. Comparison of the result obtained using this
method with other existing methods reveals that the present method is
more effective and convenient for these types of nonlinear problems.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Variational Iteration Method, Heat Transfer.
Approximate Solution of Fractional Diffusion Equation – Revisited
by S. Das
Vol. 4. n. 5, pp.
501-504
Abstract - The
article presents the approximate analytical solution of a fractional
diffusion equation with the help of powerful mathematical tool viz.,
variational iteration method. Fractional diffusion equation has special
importance in engineering and science, and constitutes a good model for
many systems in various fields. By using initial value, the explicit
solution of the equation has been derived, which accelerate the rapid
convergence of the series solution. The striking features of the article
are successful presentation of sub-diffusion characteristics of the
probability density function through numerical computation due to the
presence of reaction term for various fractional Brownian motions and
for different specified values of the considered parameters.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Fractional Derivative, Diffusion Equation, Initial Value, Sub-Diffusion, Reaction Term, Variational Iteration Method.
Applications of the Variational Iteration Method to Fractional Diffusion
Equations: Local versus Nonlocal Ones
by Guo-Cheng Wu
Vol. 4. n. 5, pp.
505-510
Abstract - The
diffusion equations with the local and the nonlocal fractional
derivatives have been used to describe the flow through disorder media.
Recently, the variational iteration method is successfully developed to
find approximate solutions of the two kinds of fractional differential
equations.
This study reveals the new development of the method and compares the
applications in two types of fractional diffusions.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Fractional Diffusion Equation, Variational Iteration Method, Lagrange Multipliers, Caputo Derivative, Riemann-Liouville Derivative, Kolwankar-Gangal’s Derivative.
Application of the Variational Iteration Method for Determining the
Temperature in the Heterogeneous Casting-Mould System
by Edyta Hetmaniok,
Konrad Kaczmarek, Damian Słota, Roman Wituła, Adam Zielonka
Vol. 4. n. 5, pp.
511-515
Abstract - In this
paper an application of the variational iteration method for determining
the temperature in the heterogeneous casting-mould system is presented.
Considered problem is modeled by means of the system of two heat
conduction equations – for the casting and for the mould, on the contact
surface of which the boundary condition of the fourth kind with non-zero
thermal resistance is defined. An example illustrating the discussed
application and confirming usefulness of this method in solving such
kind of problems is also presented.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Heat Conduction, Casting-Mould System, Variational Iteration Method.
Mathematical Modelling and Transient Analytical Solution of a Glucose
Sensitive Composite Membrane for Closed-Loop Insulin Delivery Using He’s
Variational Iteration Method
by R. Angel Joy,
L. Rajendran
Vol. 4. n. 5, pp.
516-523
Abstract - A
mathematical modelling of an enzymatic reaction and diffusion of
reactants and product inside glucose sensitive composite membrane is
discussed. The model is based on time-and position-dependent diffusivity
of species and involves the system of non-linear reaction diffusion
equations. He’s variational iteration method is used to obtain
approximate and analytical solutions of the system. A comparison of the
analytical approximation and numerical simulation is also presented.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Enzymatic Reaction, Nonlinear Partial Differential Equations, He’s Variational Iteration Method, Boundary Value Problem, Glucose Sensitive Composite Membrane.
Efficacy of Variational Iteration Method for Nonlinear Heat Transfer
Equations – Classical and Multistage Approach
by Montri
Torvattanabun, Sanoe Koonprasert, Somjate Duangpithak
Vol. 4. n. 5, pp.
524-528
Abstract - This is
paper, we are study of solving nonlinear convective-radiative cooling
equation by using the classical variational iteration method (VIM) and
modified version called the multistage variational iteration method (MVIM).
This method is based on the use of Lagrange multipliers for
identification of optimal values of parameters in a functional.
Furthermore, a theorem for the convergence of the MVIM is presented and
comparison of the results obtained by VIM, MVIM and homotopy-perturbation
method (HPM) with exact solutions.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Heat Transfer, Nonlinear Equation, Variational Iteration Method, Convergence.
Please send any
questions about this web site to
info@praiseworthyprize.it
Copyright © 2005-2014 Praise Worthy Prize