Biomedical and Biotechnology,
Arezou Soroushnia; Fariba Ganji; Seyed Mojtaba Taghizadeh
Volume 13, Issue 4 , November 2016, , Pages 1-13
Abstract
Desmopressin acetate is a potent synthetic peptide hormone. A more acceptable route of Desmopressin acetate is a potent synthetic peptide hormone. That is administered via parenteral, intranasal, and oral routes. A more acceptable route of administration with potentially good bioavailability could be ...
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Desmopressin acetate is a potent synthetic peptide hormone. A more acceptable route of Desmopressin acetate is a potent synthetic peptide hormone. That is administered via parenteral, intranasal, and oral routes. A more acceptable route of administration with potentially good bioavailability could be offered by transdermal delivery. The present work reports on the development of water-in-oil (w/o) microemulsions for the transdermal administration of desmopressin acetate. A water-in-oil nano/submicron emulsions for transdermal administration of desmopressin developed. Its skin penetration profiles determined using Franz-diffusion cell. Pseudo-ternary phase diagrams for emulsion regions constructed. Effects of hydrophilic-lipophilic balance (HLB), ratio of surfactants and co-surfactant mixture to oil phase (Smix/oil), and ratio of surfactants to co-surfactant (S/Cs) on skin flux evaluated. Skin flux was increased when S/Cs and Smix/oil were decreased, and HLB was increased. Optimized formulation was obtained as: HLB=8, S/Cs=3 and Smix/oil=5.4, with average particle size of 69nm. The optimized nano/submicron emulsions increased desmopressin skin flux 4.45 fold relative to drug solution.
Modeling and Simulation
H. Salimi; Sh. shahhosseini
Volume 15, Issue 1 , February 2018, , Pages 1-17
Abstract
Abstract Gas to liquid (GTL) process involves heterogeneous catalytic chemical reactions that convert synthesis gas to hydrocarbons and water vapor. A three phase reactor, called Low temperature Fischer-Tropsch (LTFT) is commonly applied for GTL process. In this reactor the gaseous phase includes the ...
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Abstract Gas to liquid (GTL) process involves heterogeneous catalytic chemical reactions that convert synthesis gas to hydrocarbons and water vapor. A three phase reactor, called Low temperature Fischer-Tropsch (LTFT) is commonly applied for GTL process. In this reactor the gaseous phase includes the synthesis gas, light hydrocarbons and water vapor, the liquid phase is a mixture of the heavy hydrocarbons, and the solid phase is composed of the catalyst and the waxy products. The presence of the liquid phase in LTFT reactor causes mass transfer restriction, affecting the reaction conversion. In this work a numerical simulation of the LTFT fixed bed reactor in trickle flow regime has been accomplished to understand the impact of the liquid phase on the reactor performance. For this purpose, we have developed an axisymmetric two-dimensional multiphase heterogeneous model, where contain carbon monoxide and hydrogen, are transferred into the liquid phase. The reactor consisted of a shell and a tube that was filled with the spherical cobalt catalyst. The reaction conditions were as follows: the wall temperature was 473 K, pressure was 20 bars and a gas hour space velocity (GHSV) was 111 Nml.g_cat^(-1).h^(-1). The numerical simulation results proved the negative impact of the liquid phase on the reaction conversion. The model predictions were evaluated against the reported experimental data and also compared with the result of a numerical pseudo-homogeneous model. It was found that applying the heterogeneous model instead of the pseudo-homogeneous model clearly decreases the deviation of the numerical results.
Reaction Engineering, Kinetics and Catalysts,
M. Baniamer; A. Almasi; Sh. Sharifnia
Volume 15, Issue 4 , November 2018, , Pages 1-16
Abstract
Pharmaceutical pollutants are one of the most important issues of modern life and their negative effects on the environment and human health are undeniable. In the present work, the effectiveness of the photocatalytic process was studied by two semiconductors (ZnO and V2O5) in order to remove the Diclofenac ...
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Pharmaceutical pollutants are one of the most important issues of modern life and their negative effects on the environment and human health are undeniable. In the present work, the effectiveness of the photocatalytic process was studied by two semiconductors (ZnO and V2O5) in order to remove the Diclofenac Sodium completely under solar irradiation. The study examined the impact of parameters such as the high-level range concentration of pharmaceutical, catalyst dosage, pH changes and time on the photodegradation of Diclofenac Sodium in aqueous solution. All the experiments were carried out under solar and UV irradiation to compare between the two circumstances. The optimum conditions obtained for photodegradation of Diclofenac Sodium were: reaction time 180 min, zinc oxide and vanadium pentoxide = 1 g L-1, Diclofenac Sodium concentration = 300 mg L-1 and pH = 4. In addition, chemical oxygen demand removal was investigated for all the conditions and total degradation was observed by V2O5 under optimum conditions. The study of reaction kinetics was carried out at optimum conditions and approximately a pseudo-first order kinetic model was in agreement with experimental results in each case.
Transport Phenomena,
A. Mohammadi; J. Moghaddas
Volume 16, Issue 1 , March 2019, , Pages 1-21
Abstract
In this study, nanoporous silica aerogel and silica aerogel-activated carbon composites have been synthesized using a water glass precursor by cost effective ambient pressure drying method. Equilibrium and kinetics of benzene and ethyl benzene adsorption on silica aerogel and its composites have been ...
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In this study, nanoporous silica aerogel and silica aerogel-activated carbon composites have been synthesized using a water glass precursor by cost effective ambient pressure drying method. Equilibrium and kinetics of benzene and ethyl benzene adsorption on silica aerogel and its composites have been measured in a batch mode at tree weights of adsorbent. For the first time, the experimental data have been fitted with intra-particle diffusion model for determining of diffusion coefficients. The saturation adsorption capacity of benzene and ethyl benzene vapours was 2033 mg.g-1 and 458 mg.g-1 respectively. The components uptake curves have been described by mathematical models of pseudo first order and pseudo second order models. It has been found that the pseudo first order model fits the experimental data better than the pseudo second order model. Also, the pseudo-second order model could be used for modeling of benzene adsorption over silica aerogel and silica aerogel-2% wt. activated carbon composite at the beginning of adsorption process. The diffusion coefficients of benzene and ethyl benzene within the silica aerogel were in the range of 〖2.16×10〗^(-14) - 〖6.66×10〗^(-13) m2.s-1 and 〖3.65×10〗^(-13) - 〖1.95×10〗^(-12) m2.s-1, respectively.
Separation Technology,
M.R Omidkhah; H. Azami; L. Ghaheri
Volume 16, Issue 2 , June 2019, , Pages 1-13
Abstract
Nowadays, forward osmosis (FO) with many advantages in water treatment, are so attractive for researchers and investigators that the studies are going to optimize and increase its efficiency. However one of the most controversial operating malfunctions of FO process is fouling that limits the FO global ...
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Nowadays, forward osmosis (FO) with many advantages in water treatment, are so attractive for researchers and investigators that the studies are going to optimize and increase its efficiency. However one of the most controversial operating malfunctions of FO process is fouling that limits the FO global application. In the following research, vertically aligned carbon nanotube (VACNT) on alumina membrane is introduced with high water permeability and less biofouling potential in forward osmosis for seawater osmotically dilution systems. VACNT membranes were prepared via pyrolysis of polymer into the pores of alumina. The effect of the temperature of pyrolysis process on CNT’s structure are assessed which indicated crystallinity of the CNTs increase in higher pyrolysis temperature of 800 °C. A small scale setup is designed for FO analysis and measurements of biofouling, flux and the effect of osmotic pressure were measured. Furthermore, all analysis were compared with commercial TFC membrane and results demonstrated that VACNT membrane has 40% less biofouling potential and 2 times better flux results.
Transport Phenomena,
Volume 11, Issue 4 , October 2014, , Pages 3-9
Transport Phenomena,
Volume 11, Issue 3 , July 2014, , Pages 3-15
Process Control and Engineering, Process Safety, HSE
Volume 11, Issue 2 , April 2014, , Pages 3-16
Transport Phenomena,
Volume 11, Issue 1 , January 2014, , Pages 3-18
Modeling and Simulation
Volume 10, Issue 4 , October 2013, , Pages 3-15
Energy
Volume 10, Issue 3 , July 2013, , Pages 3-13
Biomedical and Biotechnology,
Volume 10, Issue 2 , April 2013, , Pages 3-14
Transport Phenomena,
Volume 10, Issue 1 , January 2013, , Pages 3-16
Energy
Volume 9, Issue 1 , January 2012, , Pages 3-11
Transport Phenomena,
Volume 9, Issue 2 , April 2012, , Pages 3-12
Reaction Engineering, Kinetics and Catalysts,
Volume 9, Issue 3 , July 2012, , Pages 3-13
Modeling and Simulation
Volume 9, Issue 4 , October 2012, , Pages 3-16
Modeling and Simulation
Volume 8, Issue 4 , October 2011, , Pages 3-10
Petroleum and Reservoir Engineering
Volume 8, Issue 3 , July 2011, , Pages 3-15
Modeling and Simulation
Volume 8, Issue 2 , April 2011, , Pages 3-17
Petroleum and Reservoir Engineering
Volume 8, Issue 1 , January 2011, , Pages 3-14
Transport Phenomena,
Volume 7, Issue 4 , October 2010, , Pages 3-11
Petroleum and Reservoir Engineering
Volume 7, Issue 3 , July 2010, , Pages 3-16
Reaction Engineering, Kinetics and Catalysts,
Volume 7, Issue 2 , April 2010, , Pages 3-16
Petroleum and Reservoir Engineering
Volume 7, Issue 1 , January 2010, , Pages 3-12