eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1073
1079
10.24200/sci.2016.3876
3876
Development of Li-doped cubic P mesoporous silica MCM-48 as a novel humidity sensor
M. Anbia
anbia@iust.ac.ir
1
S. Kadkhodazade
2
Research Laboratory of Nanoporous Materials, Faculty of Chemistry, Iran University of Science and Technology, Tehran, P.O. Box 16846-13114, Iran.
Research Laboratory of Advanced Materials, Chemistry and Chemical Engineering Research Center of Iran, Tehran, P.O. Box 14335-186, Iran.
LiCl-doped mesoporous silica MCM-48 with cubic mesostructure, using a dierent doping concentration of LiCl, has been prepared. The LiCl-MCM-48 type materials were characterized employing XRD, FT-IR, SEM, and nitrogen adsorptiondesorption isotherm. We had the humidity sensors on a ceramic substrate with two Ag-Pd interdigital electrodes with ve ngers. The sample with 15 wt% LiCl-doped MCM-48 shows an excellent linearity in the whole humidity range of 11%-97%. It has very good response and recovery time, about 22 and 30 sec, respectively.
https://scientiairanica.sharif.edu/article_3876_1ce3429ac1d90f05135c7717a6a2c85b.pdf
SiO2
Sensors
LiCl
Impedance
porosity
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1080
1088
10.24200/sci.2016.3877
3877
Experimental and Theoretical X-ray Charge-Density Study of 1-Cycloheptylidene-2-(2,4-dinitrophenyl)hydrazine: A Hydrazone Derivative
Zahra Sharafi
zahrasharafi1@gmail.com
1
Islamic Azad University of Marvdasht
The experimental X-ray charge density analysis of a hydrazone derivative was obtained by multipolar Hansen-Coppens formalism refinement through high resolution low-temperature X-ray diffraction data at 100(1) K and the results compared to its theoretical calculation data by Gaussian wavefunctions in connection to the AIM2000 program package. The molecular properties of the title compound resulted from the combined experimental and the quantum theory of atoms in molecules (QTAIM) studies. The topological properties of the covalent bonds, intramolecular and intermolecular interactions such as hydrogen bonding, ππ, C–HO and (NO2)NO(NO2) have been investigated.
https://scientiairanica.sharif.edu/article_3877_2f67ea158bc28d14c3e7afd1eb1973b1.pdf
X-ray charge density
Hansen-Coppens formalism
QTAIM
multipolar model
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1089
1094
10.24200/sci.2016.3878
3878
Synthesis of a new T-shaped heterobinuclear Pt0-AuI complex [(t-Bu3P)2PtAu(PPh3)]BF4 from trinuclear gold cluster complex [(PPh3)Au]3(-O)BF4
S. Jamali
gvuencsf@scientiaunknown.non
1
M.M. Ashtiani
2
D. Milic
3
Department of Chemistry, Sharif University of Technology, Tehran, P.O. Box 11155-3516, Iran.
Department of Chemistry, Sharif University of Technology, Tehran, P.O. Box 11155-3516, Iran.
Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia.
The heterobinuclear platinum(0)-gold(I) complex [(t-Bu3P)2PtAu(PPh3)] BF4, 5, was synthesized by the reaction of trinuclear cluster complex f[(PPh3)Au]3(- O)gBF4, 4, with one equiv of [(t-Bu3P)2Pt] at room temperature. The heterobinuclear complex 5 was characterized using multinuclear NMR spectroscopy and elemental microanalysis and was further identied by single crystal X-ray structure determination. Crystal structure of 5 shows a T-shaped geometry with an unsupported short distance Pt-Au dative bond.
https://scientiairanica.sharif.edu/article_3878_1bc37c61bf39a7ae0a3a3c4bf32242d2.pdf
Synthesis
Metal
Complex
Platinum
Gold
Cluster
Binuclear
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1095
1101
10.24200/sci.2016.3879
3879
A Fast and Highly Efficient Protocol for Synthesis of Dihydropyrano[2,3]PyrazoleCompounds Using Acidic Ionic Liquid 3-Methyl-1-Sulfonic Acid Imidazolium Chloride ([Msim]Cl)as Catalyst and Green Solvent
Behjat Pouramiri
b.pooramiry@yahoo.com
1
Esmat Tavakolinejad Kermani
etavakoly@yahoo.com
2
Department of Chemistry, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran
Department of Chemistry, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran
A new, efficient, and environmentally benign protocol for the one-pot, four-component synthesis of dihydropyrano[2,3-c]pyrazoles by condensation of ethylacetoacetate, hydrazine hydrate, aromatic aldehyde, and malononitrile catalyzed by3-methyl-1-sulfonic acid imidazolium chloride([Msim]Cl) as an ecofriendly catalyst with high catalytic activity and reusability at 30 0C under solvent-free conditions is reported. The reactions proceed to completion within 5–15 min in 87–97% yield.
https://scientiairanica.sharif.edu/article_3879_e872f69492a2f0c49017992bb3757d0f.pdf
Multi-component reaction (MCR)
Pyrano[2
3-c]pyrazole
Green chemistry
Ionic liquid
Heterocycle
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1102
1110
10.24200/sci.2016.3880
3880
Nano-ordered MCM-41-SO3H an efficient catalyst for the synthesis of N-substituted pyrroles in water
Hossein Ghafuri
1
Atefeh Emami
2
Mohammad G. Dekamin
3
Division of Organic Chemistry, Department of Chemistry, Iran University of Science and Technology, Tehran 1684613114, Tel: +98 21 77240540, +989127399295: fax: +98 21 77491204. Iran
Division of Organic Chemistry, Department of Chemistry, Iran University of Science and Technology, Tehran 1684613114, Tel: +98 21 77240540, +989127399295: fax: +98 21 77491204. Iran
Division of Organic Chemistry, Department of Chemistry, Iran University of Science and Technology, Tehran 1684613114, Tel: +98 21 77240284, +989122936523: fax: +98 21 77491204. Iran
Condensation of 2,5-dimethoxytetrahydrofuran and aniline derivatives has been carried out in aqueous media in the presence of mesoporoushydrogen sulfated MCM-41 (MCM-41-SO3H). The reaction is smoothly catalyzed by very low loading of heterogeneous MCM-41-SO3H to afford a wide variety of N-substituted pyrroles. This procedure is clean, environmentally friendly and has many advantages including short reaction time, high yields, low cost and simple work-up. The catalyst could be recycled at least 3 times without substantial decrease of its catalytic activity.
https://scientiairanica.sharif.edu/article_3880_98d36972ed5d1f67c0f0b6009eb26449.pdf
Amines
N-substituted Pyrroles
Clauson-Kaas condensation
MCM-41-SO3H
Mesoporous Hydrogen sulfated-MCM-41 (MCM-41-SO3H)
Green chemistry
In Water Synthesis
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1111
1115
10.24200/sci.2016.3881
3881
BF3/nano-sawdust as a green, biodegradable and inexpensive catalyst for one-pot synthesis of tri-substituted imidazoles under solvent free conditions
Bi Bi Fatemeh Mirjalili
fmirjalili@yazd.ac.ir
1
A. Bamoniri
bamoniri@kashanu.ac.ir
2
R. Zare Reshquiyea
3
Department of Chemistry, College of Science, Yazd University, Yazd, P.O. Box 89195-741, Iran
Department of Chemistry, College of Science, University of Kashan, Kashan, Iran.
Department of Chemistry, College of Science, Yazd University, Yazd, P.O. Box 89195-741, Iran
BF3/nano-sawdust as a green, inexpensive, natural, biodegradable and readily available biopolymer solid acid catalyst was synthesized and characterized. This catalystwas used successfully for the synthesis of various tri-substituted imidazoles in high yields under solvent free conditions.
https://scientiairanica.sharif.edu/article_3881_9089f5924598a0fc3d4ea4feb681966a.pdf
Sawdust
BF3/nano-sawdust
Tri-substituted imidazoles
Solid acid
Biodegradable catalyst
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1117
1127
10.24200/sci.2016.3882
3882
Ionic polymer-metal composites (IPMC) from recycled Flemion membrane used in chlor-alkali industry
Saeed Taghavi
1
Fereidoon Mohammadi
2
Jalal Barzin
3
Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran, Iran
Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran, Iran
Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran, Iran
A cost effective IPMC was fabricated by using recycled Flemion membrane from chlor-alkali industry. An even distribution of platinum particles on the surface and the bulk was shown by line SEM-EDX. Pt particles and the stiffness of the recycled IPMC were gradually increasing during impregnation-reduction process to form a conventional fractured metallic surface layer displaying discrete islands according to SEM photographs. A highly reproducible current-time diagram was obtained at even low voltages despite no observable motion and no offset current due to water electrolysis by chronoamperometry. However, the sensible motion was observed after 1.5 V with a significant increase in current and appearance of offset current developing with voltage. Due to capacitive characteristics of the recycled IPMC, peak current decreases with frequency linearly while the plateau current was observed only at low frequencies or time periods, Tp, longer than five times constant. The normalized maximum tip force generated at different voltages along with tip displacement and Young’s modulus were measured by load cell and compared with those of a Nafion-based IPMC (N-IPMC). Very close values were obtained confirming the recycling does not have a sensible effect on the mechanics of the recycled IPMC.
https://scientiairanica.sharif.edu/article_3882_a78eed09e2c63f441b8e52beff1c262c.pdf
Recycle based Flemion
Ionic polymer metal composite
Bending motion
actuator
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1128
1135
10.24200/sci.2016.3883
3883
Influence of calcination parameters on the properties of alumina as a catalyst support
S. Komeili
1
M. Takht Ravanchi
2
A. Taeb
3
Department of Chemical Engineering, Iran University of Science and Technology, Tehran, P.O. Box 16765163, Iran.
National Petrochemical Company, Petrochemical Research and Technology Company, Tehran, P.O. Box 1435884711, Iran.
Department of Chemical Engineering, Iran University of Science and Technology, Tehran, P.O. Box 16765163, Iran.
The preparation history of Al2O3 strongly determines its properties for the application as a catalyst support. The interaction of calcination heating rate and temperature and its influence on the structural, textural, and acidic properties of alumina were studied. Commercial-alumina was calcined at 800C, 900C, 1000C, 1050C, 1100C, and 1150C by 2.5C/min, 5C/min, and 10C/min. By increasing temperature up to 1050C, transition aluminas (, , and ) were reported, but the heating rate accelerated phase transformation and changed the amount of each phase in the samples. At 1100C and 1150C, -alumina appeared. Mesopore alumina with dierent surface areas (265-126 m2/g) was synthesized at calcination temperature from 800C to 1050C; when temperature reached 1100C, the surface area decreased drastically and was around 14 m2/g. Interaction of heating rate on the temperature had minimal eect on the surface area of samples, but considerable eect on the acidic properties. The intensity of acidic properties was aected by heating rate with nonlinear proles. By increasing the heating rate, the ratio of Al cations occupied tetrahedral per octahedral sites and defect of crystal structures increased, so the surface acidity of aluminas was increased.
https://scientiairanica.sharif.edu/article_3883_bc45df7a7bcb32bb72a23f6ede3ec4a5.pdf
Alumina
Calcination
Acidic property
Textural
Structure
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1136
1143
10.24200/sci.2016.3884
3884
Separation of Helium from Gases Using the Synthesized Hydroxy Sodalite Membrane
MohammadJavad Vaezi
m_vaezi@sut.ac.ir
1
Yaser Bayat
2
Ali Akbar Babaluo
a.babaluo@sut.ac.ir
3
Sirous Shafiei
4
Sahand University of Technology
Sahand University of Technology
Sahand University of Technology
Sahand University of Technology
The goals of this work are to synthesize and evaluate the potential of hydroxy sodalite membrane in the separation of helium from natural gas. Sodalite membrane was synthesized via direct hydrothermal method (conventional heating) on tubular alumina support. It was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and single gas permeation using helium and N2. After drying of the membrane, permeances of single gases were found to be of the order Helium > CH4 > N2 > CO2 at low temperatures and the membrane was impermeable to N2, CO2 and CH4 at high temperatures (>85 °C). In the investigated range of temperature 35-180 °C, membrane performance tended to high selectivity. The maximum separation factors (helium/N2 ~ 8.8, helium/CO2 ~ 16.5 and helium/CH4 ~ 5) with acceptable permeance were observed at 85 °C.
https://scientiairanica.sharif.edu/article_3884_2ccff0b810c752ec7bc865d15af3e483.pdf
Helium Separation
Inorganic Membrane
Hydroxy Sodalite
Gas Permeation
High Temperatures
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1144
1159
10.24200/sci.2016.3885
3885
Physicochemical Properties and Stress-Strain Compression Behaviors of a Waste based Magnetorheological Elastomers
Ubaidillah Ubaidillah
ubaidillah@uns.ac.id
1
Saiful Amri Mazlan
amri@ic.utm.my
2
Joko Sutrisno
3
Iwan Yahya
4
Fitrian Imaduddin
5
Iwany Acoustic Research Group
Malaysia-Japan International Institute of Technology
Chemical Engineering Department
Physic Department
Vehicle System Engineering
This study reports a reclamation method of ground tire rubber (GTR) and electronic wastes into a tunable stiffness composite namely magnetorheological elastomers (MREs). The composite matrix was the GTR that has been separated from its metals and yarns. Meanwhile, the fillers were fabricated from magnetic cores of the cathode ray tubes (CRTs) monitor waste through high energy ball milling in wet condition. Some physicochemical characterizations of the powders were initially conducted to collect the physical and chemical properties. Based on the examination, the ground powders were identified as pure magnetite (Fe3O4) having low remnant and high magnetization. The MREs samples were prepared by high-temperature high-pressure sintering. The mixed of crumb rubber and magnetite powder was vulcanized under simultaneous pressure, and temperature in the absence of magnetic fields resulted in an isotropic MREs type. The specimens were examined their abilities in responding to the external magnetic field through static and dynamic compression test. The experimental investigation showed that the static and dynamic stresses of the stiffness increased by the increment of magnetic fields until a particular point of flux density. The tunability of the stiffness indicated that the elastomers can provide wide ranges of the storage and loss modulus.
https://scientiairanica.sharif.edu/article_3885_1a4ea5b0e33923c828ee024a8fa08bbc.pdf
magnetorheological elastomers
ground tire rubber
electronic waste
magnetite powders
compression mode
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1160
1174
10.24200/sci.2016.3886
3886
Oxidation of H2S to Elemental Sulfur over Alumina Based Nanocatalysts: Synthesis and Physiochemical Evaluations
Mohammad Rezaee
1
Mohammad Kazemeini
kazemini@sharif.edu
2
Moslem Fattahi
moslem.fattahi@gmail.com
3
Ali Morad Rashidi
4
Leila Vafajoo
vafajoo@azad.ac.ir
5
Sharif University of Technology
Department of Chemical Engineering, Abadan Faculty of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran
RIPI
Chemical and Environmental Engineering Group, Islamic Azad University, Tehran South Branch, Tehran, Iran
In this paper oxidation of the H2S into elemental sulfur over synthesized alumina-based nanocatalysts was physiochemically investigated and the results compared with a commercial Claus catalyst. The wet chemical, co-precipitation and spray pyrolysis techniques employed to synthesize several alumina nanostructures. Then, the SEM, XRD and ASAP analysis methods utilized to characterize in order to choose the best nanocatalyst. The sulfur andH2S contents determined through the standard UOP techniques. Amongst these as-synthesized materials, Al2O3-supported sodium oxide prepared through the wet chemical and Al2O3 nanocatalyst via spray pyrolysis methods were the most active catalysts for the purpose at hand. In addition, the titanium dioxide nanostructure and a hybrid of nano alumina support (made via the wet chemical method) decorated on the carbon nanotube prepared for this goal. Moreover, the statistical design of experiments screening of the significant synthesizing parameters performed through the Box-Behnken (e.g.;Response Surface Methodology (RSM)) technique. Ultimately, the best chemically characterized nanocatalyst was subjected to evaluations in a fixed bed reactor while effects of temperature, metal loading and GHSV understudied. It was observed that, the alumina nanoparticles prepared through the wet chemical and spray pyrolysis methods led H2S into elemental sulfur in a reproducible manner with 97 and 98% conversions, respectively. Both of these were more desirable than that obtained utilizing the commercial catalysts (i.e.: CR-3S and CRS-31) providing nearly 96% conversion.
https://scientiairanica.sharif.edu/article_3886_4a517a9b061a54ab52d9c032d73f3e3c.pdf
H2S
Claus process
Al2O3
Spray pyrolysis method
Wet chemical technique
Nano catalyst
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1175
1183
10.24200/sci.2016.3887
3887
Study of self-diffusion in two binary solutions, glycerol-water and methanol-water using diffusion-ordered spectroscopy
E. Fadaei
1
M. Tafazzoli
2
Department of Chemistry, Sharif University of Technology, Tehran, P.O. Box 11155-9516, Iran.
Department of Chemistry, Sharif University of Technology, Tehran, P.O. Box 11155-9516, Iran.
The concentration and temperature behaviors of the self-diffusion coecient were analyzed in glycerol-water and methanol-water solutions using Diusion-Ordered Spectroscopy (DOSY) experiment. Our results indicate that the self-diusion coecient dips with increasing concentration and decreasing temperature. The concentration behavior shows that there is hydrogen bond interaction between water and alcohol, which declines the self-diffusion coecients of both in the aqueous binary mixtures. The self-diffusion activation energies were estimated 13.6, 29.4, and 32.8 (kJ/mol) for methanol and 24.8, 25.5, and 27.6 (kJ/mol) for water in the methanol-water solutions with 0.03, 0.10, and 0.20 mole fractions of methanol, respectively. The methanol self-diusion activation energy, in the very dilute methanol-water solution (0.03 mole fraction of methanol), is consistent with the formation of iceberg-like structure which helps methanol to diuse quickly. The water self-diffusion activation energies indicate that water network is not signicantly perturbed by methanol and the water molecules diuse in the same manner in methanolwater solutions.
https://scientiairanica.sharif.edu/article_3887_ad46e24ca109b1a9733e7ffacebe5c23.pdf
Self-diffusion
DOSY NMR
Glycerol
methanol
Concentration eect
Temperature eect
eng
Sharif University of Technology
Scientia Iranica
1026-3098
2345-3605
2016-06-01
23
3
1184
1194
10.24200/sci.2016.3888
3888
The Construction and Application of a SimplifiedPore Network ModelBased on Computerized Tomography
Yiting Xie
1
Zhaohui Chen
2
Zhimin Du
3
State Key Lab of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, China
School of Oil & Natural Gas Engineering, Southwest Petroleum University, Chengdu, China
School of Oil & Natural Gas Engineering, Southwest Petroleum University, Chengdu, China
A simplified pore network model divided pore structure into cube lattices was developed base on the digital core extracted from micro computerized tomography (μ-CT) in this study. It rolled the complex topology and connectivity of pore structure into adjacent cubes. The static property of each cube was determined by the statistic CT data. The connectivity of adjacent cubes and flow regime were determined by the capillary pressure difference which is a function of tunnel size, interfacial tension, wet contact angle, and external pressure gradient. In this simplified pore network model, the flow capacity properties are determined by number and size distribution, mobile tunnels, and fluid viscosity. The flow velocity and sweep efficiency are non liner as mobile tunnels increase nonlinearly with increasing driving force before all tunnels start flowing. The critical pressure gradient that changes the non liner flow to liner flow was performed as the threshold pressure gradient. The dynamic mobile performance of oil in place (OIP) is determined by the number of mobile tunnels and their diameter distribution for different pressure gradient. The relationship of microscopic sweep efficiency, water cut and pressure gradient to oil recovery can be quantified by flow simulation in this pore network model.
https://scientiairanica.sharif.edu/article_3888_92fd372ee2949fe3a36d2acac3bf7b33.pdf
pore network model
flow capacity
non liner flow
computerized tomography