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Numerical Simulation and Spice Modeling of Organic Thin FilmTransistors (OTFTs) A.D.D. Dwivedi  

Abstract: As organic thin film transistors are playing important role in low cost, large area and flexible integrated circuits,
there is urgent need of accurate modeling and simulation of these devices with emphasis of compact modeling suitable
in integrated circuit simulation using Spice like simulators. This paper presents a 2D numerical simulation of pentacene
based organic thin film transistors. Also a spice model extraction methodology of OTFTs base on Silvaco's UOTFT
model is presented for circuit simulation. The numerically simulated results are in good agreement with OTFT spice
modeling results. The Organic TFT model is extracted from the numerically simulated data and further it is used in circuit
simulation of CMOS like hybrid inverter and five stage ring oscillator circuit realized from hybrid inverter. In the hybrid
inverter circuit an amorphous silicon TFT is used in place of the NMOS devices and a Pentacene based TFT is used in
place of the PMOS devices. Circuit simulation results proves the applicability of the model in circuit design of organic thin
film based transistors.

Influence of Stress Relaxation on the Magnetization Process of Hitperm-Type Glass-Coated Microwires A. Talaat P. Klein

Abstract: The remagnetization process of most amorphous and nanocrystalline glass-coated microwires with positive
magnetostriction coefficient occurs through the single and large Barkhausen jump. This article encompasses a study on
the magnetization process of thin Hitperm-type glass coated microwires. The complex stress distribution inside these
microwires enables us to investigate the influence of; the measuring frequency, applied tensile stresses, as well as
current annealing, and conventional annealing at wide range of temperatures. A systematic elucidations have been
discussed in the framework of the microwire's geometries and the shape anisotropy that arises during its fabrication
process, with the aim to provide an assessment of the criteria for selecting the necessary conditions to be designed in
high-performance sensors.

On Some Properties of Cylindrically Transformed Systems With R(􀀁) Symmetry and Phase Dynamics Anirban Ray* A. Roy Chowdhury

Abstract: Nonlinear dynamical systems with R(􀀁) symmetry are shown to behave in a very interesting manner under a
new transformation of dynamical variables. Such property helps to identify the phase dynamics embedded in the system but
preserves the basic property of the attractor intact. This is very similar to those phenomenon discussed with the help of
covering transformation in the literature. The Poincare sections obtained are identical to those obtained through covering
transformation and hence indicate to a similar topological structure and identical dynamical characteristics.

Investigation of Intrinsic Stress and Transport Properties of Fe/P-Si (001) Schottky Heterojunction Anirban Sarkar,* S. Bhaumik

Abstract: We present a comprehensive study on the growth morphology, the electrical and magnetic transport
properties of thin iron (Fe) film on p-Si(100) substrate. The structural analysis revealed the growth of an amorphous Fe
film, with low crystalline ordering and granular structure. The resistivity of the film was observed to deviate from the usual
metallic behavior at lower temperature revealing a tunneling type conductance. This was also reflected in the
magnetoresistance measurement of the film. The film show high positive (negative) magnetoresistance at all
temperatures (below 10 K) on application of out-of-plane (in-plane) magnetic field. The current-voltage (I-V)
measurement of Fe/p-Si Schottky heterojunction exhibits good rectifying property. The ideality factor (n) and Schottky
barrier height 􀀁 b ( ) of the device, at room temperature, were obtained from fitting the I-V curves. The carrier
concentration of the semiconductor substrate was evaluated from the capacitance-voltage (C-V) measurements. From
the measurements large deviation from the ideal value of the diode parameters was observed. All the results thus
obtained show a strong correlation between the stress and the transport measurements.

PbZrO3-Based Antiferroelectric Thin Film Capacitors with High Energy Storage Density Mao Ye Peng Lin

Abstract: A series of 400-nm-thick sandwich structured Pb(1+x)ZrO3/(Pb,Eu)ZrO3/Pb(1+x)ZrO3(PZO/PEZO/PZO) antiferroelectric
thin films with different Pb excess content (x) (x=0%, 10%, 20%, and 30%) in the PZO precursors have been
successfully deposited on Pt(111)/Ti/SiO2/Si substrates by a sol–gel method. The effects of Pb excess content on the
dielectric properties, and energy storage performance of the PZO/PEZO/PZO thin films have been investigated in detail.
It is found that all the films show a unique perovskite phase structure. With increasing Pb excess content in the PZO
precursors, P-E hysteresis loop changes from slanted to square shape. Meanwhile, a larger antiferroelectric to
ferroelectric switching field (EAF) and ferroelectric to antiferroelectric switching field (EFA) are observed in the films with
higher Pb excess content. When increasing Pb excess content from 0% to 30%, the energy storage density of the
sandwich structured films is remarkably improved from 11.4 to 14.8 J/cm3 at 1000 kV/cm.

Fundamental Properties and Origin of the High-Tc Cuprate Superconductors: Development of Concepts A. Bechlaghem*  

Abstract: After a review of the fundamental properties of the high-Tc cuprate superconductors, we evaluate and study
the major parameters of these compounds. In this approach, we consider the attractive interaction is due to the phonons
at low temperature, but at high temperature it is related to the magnetic excitations. Analytical expressions for the
coherence length 􀀁, the isotope coefficient 􀀁 and the superconducting gap ratio R = 2􀀁(0) /kBTc are obtained for the
case where the Fermi level is close to the van Hove singularity. This model explains simultaneously high Tc, large gap
energy 􀀁(0), short coherence length 􀀁 and small values of the isotope coefficient 􀀁 . Our theoretical values are in a
good agreement with experimental results.

Method of Green’s Functions for the Problem of Sound Diffraction on Elastic Shell of Non-Analytical Form S.L. Ilmenkov A.A. Kleshchev

Abstract: The real scatterers have a non–analytical form and, therefore, the variable separation method (Fourier series
method) for calculation of the reflected sound field cannot be applied to them. This article presents the method of
Green’s functions and methods of the dynamic theory of elasticity for the solution of the problem of sound diffraction on
elastic shell of a non–analytical surface. Furthermore, this work includes the detailed analysis of the solution of this
problem and calculation of the angular characteristics of the sound scattering by non-analytical scatterers.

Advance in the Analysis Models for Characterizing Multi-Layered Interdigital Capacitors Kwong Wai Mak* Jianhua Hao

Abstract: The performances of multi-layered interdigital capacitors are commonly simulated by computer software.
However, it is the time-consuming process. Besides simulations, the analytic models with closed form expressions
provide convenient methods in particular usages, such as characterizing ferroelectric materials. This article briefly
reviews the development in the expressions for analytic models. We provide an overview of partial capacitance
technique and conformal mapping technique, which are used for formulating expressions. In addition, three common
models used these techniques are presented. The differences of models and applications are also discussed.

Meson Acceleration and Handling Yuko Nakamura*  

Abstract: The fundamental engineering techniques, such as high electric field produced by rf systems or lasers, strong
magnetic field produced by the MegaGauss techniques and the various methods for high-energy particle handling, have
been promoted rapidly, and the fields have been improved drastically. Those techniques are expected to explore the
new frontier by using elementary particles for industrial applications. One of the scenarios to accomplish the application
trials by elongation of the short lifetime of mesons is described in this paper.

Impulse Strong Mirror Field for High-Energy Particle Handlings Masakazu Takayama Koichi Kindo

Abstract: The technologies for generating strong magnetic flux density of 10 T ~ 1000 T have been developed and
become to be utilized for fundamental science studies, especially for solid-state physics. These technologies enable to
control the high-energy particles in a compact region, and explore the new frontier of nuclei conversions and nuclear
fusion studies. The methods to generate strong mirror field for high-energy particle confinement and handlings are
described in this paper.

New Approach for Designing of High-Energy Circular Particle Accelerators Eiji Nakamura1-  

Abstract: New particles and new nuclei have been discovered by artificial techniques recently. High-energy particle
accelerators work the important roles to bring such discoveries. The applications of the particles are being discussed at
various communities as a next step to get new technologies. The life-time of the particles are very short to handle by
conventional techniques. It can be extended by the theory of relativity. The compact particle accelerator, which enables
rapid acceleration, is required especially for the industrial applications. The possibility to satisfy the isochronous
condition in the case of DC and uniform magnetic field is discussed here by getting back to the fundamental theoretical
approach

Saving Energy and Uninterruptible Power System for Large Scale Research Facility Hikaru Sato*  

Abstract: Large Scale Research Facility such as J-PARC is faced on a budgetary deficit and also environmental
concerns. Then, affordable and sustainable energy supply should be considered to continue and develop the big
science. Magnets of the synchrotron are excited by a pulse operation power supply, and then the load fluctuation should
be a severe problem. An energy storage system, such as superconducting magnetic energy storage (SMES), flywheel
generator so far are expected to protect the load fluctuation and the instantaneous voltage drop. The author has
investigated about the application to the particle accelerator power supply of SMES. The resent status and the future
energy storage systems for large-scale research facilities, especially a particle accelerator facility, are described in this
paper. This engineering technique is effective for office buildings and hospitals so far. Feasibility of the sustainable
energy supply will be discussed.

Developments on Next-Generation Beam Handling of High-Energy Particles by using Non-linear Characteristics Eiji Nakamura  

Abstract: Various developments had been conducted to produce a fast-response magnet by the traditional concepts
based on the use of linear-characteristic elements, but the improvement is limited by the transmission theory. The
application of non-linear phenomena is important to achieve further improvements. The recent progress and the future
plan of the developments to produce a fast-response and strong field for high-energy particle handling are described
here.

Space-Group Approach to the Wavefunction of a Cooper Pair: Nodal Structure and Additional Quantum Numbers for Sr2RuO4 and UPt3 V.G. Yarzhemsky  

Abstract: Induced representation method and Mackey theorem on symmetrized squares were applied to construct zerototal-
momentum two-electron states in solids, corresponding to Cooper pairs in unconventional superconductors. In this
approach the structure of two-electron states depends on the position of one-electron wave vector in a single-electron
Brillouin zone. It is shown, that the decomposition of total two-electron basis set results in repeating multidimensional
irreducible representations. It is obtained, that in order to label repeating irreducible representation two additional
quantum numbers are required: irreducible representation of wave vector group for symmetry planes and directions and
quantum numbers on an intermediate group for a general point in a Brillouin zone. Theoretical results are applied to
unconventional superconductors UPt3 and Sr2RuO4.

Superconductor-Dielectric Photonic Band Gap in Ultraviolet Radiation Arafa H Aly*  

Abstract: Optical properties of a high-temperature superconductor/dielectric (HTcScD) in the UV operation range are
theoretically investigated. We have obtained and performed the calculations of optical reflectance and transmittance
spectra. The calculated wavelength-dependent reflectance and transmittance for the structure superconductor/dielectric
shows that the threshold wavelength is significance by the angle of incidence and the polarization of waves. The
variance of the intensity and the bandwidth of the transmission and reflection are strongly dependent on the different
thicknesses, different temperatures, and different incident angles as well as we obtained the different band gaps
dependent on the thickness of layers. Also we have examined the influence of the increased of the number of periods on
the transmittance and reflectance spectra as well as on the band gap positions

Effect of Silver Substitution Threshold on the Superconducting Properties of IG Processed Bulk YBCO/Ag Composite Superconductors R. Parthasarathy  

Abstract: In this article, we report anomalous substitution of Ag in Cu sites in Y-123 lattice during the fabrication of bulk
YBCO/Ag composites via the Infiltration Growth Processing technique. We have observed concentration quenching of
Ag in the Y-123 unit cell which implies a threshold for Ag substitution in Cu sites. We find gradual variation in properties
with increase in Ag content up to a threshold value beyond which the superconducting properties are altered
significantly. We discuss the effect of substitution threshold of Ag on the magnetic and superconducting properties of
these composites and the optimum substitution level of Ag for enhanced properties.

Enhancement of Phase Formation and Critical Current Density in (Bi,Pb)-2223 Superconductor by Boron Addition and Ball Milling N.G. Margiani1,* S.K. Nikoghosyan

Abstract: The effects of crystalline boron addition and ball milling on the phase formation and transport properties of
(Bi,Pb)-2223 HTS have been studied. Samples with nominal composition Bi1.7Pb0.3Sr2Ca2Cu3BxOy, x=0 - 0.5, were
prepared via a solid state reaction route. Superconducting properties of undoped (reference) and boron-added (Bi,Pb)-
2223 compounds were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), resistivity and
transport critical current density (Jc) measurements. Obtained results have shown that boron additive leads to the
acceleration of high-Tc phase formation and enhancement of Jc in (Bi,Pb)-2223 superconductor. The estimated volume
fraction of (Bi,Pb)-2223 phase increases from ~25 % for reference specimen to ~75 % for x=0.15. Moreover, strong
increase in the Jc was observed for the x=0.15 sample (Jc=340 A/cm2), compared to a reference sample (Jc=115 A/cm2).
We have studied the effect of high-energy ball milling on Jc in reference and x=0.15 samples. Addition of B in
combination with the ball milling leads to the further enhancement of Jc up to 490 A/cm2, whereas the ball milling of
reference specimen causes the marked decrease in both Jc and Tc values. Improvement of superconducting properties in
(Bi,Pb)-2223 superconductor can be attributed to the acceleration of high-Tc phase formation along with the
enhancement of intergrain coupling due to the elemental boron addition.

Hydrophilic Nanocomposite Membranes for the Pervaporation Separation of Water - Ethanol Azeotropic Mixtures Thomasukutty Jose Soney C George*

Abstract: Bentonite nanoclay reinforced Poly (vinyl alcohol) (PVA) nanocomposite membranes were used for the
separation of azeotropic composition of water – ethanol mixtures by pervaporation process. Fourier – transform infrared
(FTIR) spectroscopic studies revealed the interaction of bentonite nanoclay and the PVA matrix. The dispersion and
distribution of nanoclay in the polymer matrix was demonstrated by transmission electron microscopic analysis (TEM).
The intrinsic membrane properties with filler loading were also investigated. The results indicate that the hydrophilic
nature of the nanoclay influenced the pervaporation to a greater extent. The hydrophilic nature and surface roughness of
the nanocomposite membranes was analyzed by atomic force microscopic (AFM) analysis. The pervaporation process
illustrates that the permeation flux increases and the separation factor decreases with nanoclay loading. The instrinsic
selectivity, which reflects the membrane performance was maximum for 1 wt% clay loaded membranes. PVA with 1 wt%
nanoclay loading showed better pervaporation performance. The separation factor of the 1 wt% nanoclay membranes
increased to 13, i.e. nearly 4 times more than that of neat PVA membranes. Membrane selectivity also increased to
254% than that of pristine PVA membranes. Thus at lower filler loading, maximum separation was achieved. The
increase in nanoclay loading is favorable to improve intrinsic permeance at the cost of decrease in selectivity.

Theoretical Analysis of Butane Isomers Separation using Various Membrane Process Configurations Abbas Aghaeinejad-Meybodi Kamran Ghasemzadeh2,*

Abstract: The main purpose of this study is performance investigation of single stage membrane, continuous membrane
column (CMC) and countercurrent recycle membrane cascade (CRC)during butane isomers separation in the typical
LPG plant. As a case study, the required total membrane area and compressor duty for three type configurations for
separation of butane isomers produced in LPG unit of Tabriz refinery was evaluated. For this purpose, a typical H-ZSM-5
zeolite membrane with n-butane/isobutene selectivity around 10 was considered. The optimum scheme was then
selected by means of minimum total membrane area and compressor duty requirements. Moreover, the effects of key
parameters such as selectivity, feed to permeate pressure ratio and composition of the permeate stream on the
membrane surface area was evaluated

Separation of 1,3-Propanediol by Nanofiltration Method Seda Eristurk Ozture Nalan Kabay

Abstract: The application potential of nanofiltration (NF) method on the separation of 1,3-propanediol (1,3-PDO) from
synthetically prepared fermentation broth was investigated. The rejection tests at different pressures (10, 20, 30 bar) and
pH values (7 and 10) were performed on laboratory scale using Desal DL-5 NF membrane. The rejection of succinic
acid, having the molecular weight larger than or closer to the molecular weight cut-offs (MWCOs) of Desal-5 DL NF
membrane was 100% independent of operating pressure and pH. The results of this study clearly showed that NF
process is a very promising pretreatment step for the removal of volatile organic acids from the fermentation broth.

Mechanics and Pervaporation Performance of Ionic Liquid Modified CNT Based SBR Membranes - A Case Study for the Separation of Toluene/Heptane Mixtures Jiji Abraham Thomasukutty Jose

Abstract: SBR/ionic liquid modified CNT Nanocomposites were prepared using different concentration of CNT. Nano
scale dispersion of CNT affected the properties of SBR. The results have been compared with the unfilled SBR films.
Cure characteristics and mechanical properties such as tensile strength, modulus, abrasion resistance and hardness
were measured for different composites. Morphological behaviour and structural characteristics of the composites were
investigated by AFM, TEM, FTIR and Raman spectroscopy. Microstructural development in presence of filler and
interfacial interaction between modified CNT and polymer matrix led to enhanced properties. The pervaporation
performances of membranes were analysed using a toluene/heptane mixture. Membranes displayed high selectivity
towards heptane. The influence of feed composition on pervaporation was also analysed. The 5 phr CNT loaded
membrane showed enhanced membrane permeance and selectivity value, an improvement of 18% over the neat
polymer. A drop in selectivity and an increase in permeation rate were observed at higher CNT loadings.

Ibuprofen Recovery from Aqueous Solutions by Supported Liquid Membranes Teresa A. Razo-Lazcano

Abstract: Pharmaceuticals recently have acquired a big importance because of its growing detection in wastewater. The
propionic acid derivatives, such as ibuprofen, are among the most commonly anti-inflammatories used by population. For
this reason it is necessary to develop a friendly separation technique with environment, like the Supported Liquid
Membranes (SLM). In this work, SLM have been prepared in order to recover ibuprofen from aqueous solutions. Two
different organic phases were evaluated (dodecane and Parleam 4), as well as trioctylamine as carrier, and Abil EM 90
as surfactant in the preparation of SLM. The SLM prepared was tested in the IBP transfer process through the
membrane, from feed phase to stripping phase. The results showed that it is possible to recover almost 98% of IBP, this
using the SLM and a phosphate buffer solution of pH 7 like stripping phase.

Effect of Inclusion of 1-Butyl-3-Methylimidazolium Trifluoromethanesulfonate on CO2 and N2Permeabilities for PVDF and PVDF-HFP Membranes Takashi Makino1,* Mitsuhiro Kanakubo

Abstract: The CO2 and N2 permeabilities for polymer inclusion membranes, consisting of 1-butyl-3-methylimidazolium
trifluoromethanesulfonate ([bmim][TfO]) in poly (vinylidenedifluoride) (PVDF) and poly (vinilidenedifluoride-cohexafluoropropylene)
(PVDF-HFP), at the temperatures from 298.2 K to 348.2 K, have been evaluated. The PVDF and
PVDF-HFP membranes, containing 75 wt% of [bmim][TfO], had the CO2 permeabilities of 585 and 976 barrers,
respectively, and the CO2 selectivities of 15 at 348.2 K. These values were higher than those of the supported ionic liquid
membrane of [bmim][TfO] (428 barrers and 12). Furthermore, the Differential scanning calorimetry and Raman
spectroscopy were performed to analyze the micro-structures of membranes. These analyses indicate that the polymer
matrix was plasticized and the polymorphs changed from the non-polar α-phase to the polar β-phase by the addition of
[bmim][TfO]. According to the solution-diffusion transport mechanism, it is concluded that the inclusion membranes with
the sufficiently plasticized, i.e. phase-changed, PVDF and PVDF-HFP membranes absorbed the larger amount of gas
species than the neat [bmim][TfO], and PVDF-HFP is more effective than PVDF for the enhancement in gas absorption.

A Vegetable Oil-based Green Process for the Membrane Extraction of Ionic Solutes M. Hossain*  

Abstract: Extraction or removal of the polluting components can be accomplished by a variety of physical, chemical and
biological methods. Solvent extraction has demonstrated as one of the promising methods to accomplish the extraction
or removal of ions more or less selectively from the source streams. The processes, especially when operated in
membrane modules, have been successful and effective in reducing the pollutant concentration. In the development of
these processes in to industrial operations the solvents (or the extracting phase) used or recommended in the literature
are from non-sustainable source, they have undesirable properties (toxic, corrosive and health and safety issues). In
recent years there have been research work to examine the feasibility of other solvents from sustainable sources and
with good characteristics to overcome or minimize some of the above adverse effects. In this paper, the effectiveness of
sunflower oil (as a model for vegetable oil), is described in extraction (or removal) of a polluting component in a smallscale
membrane contactor. The components are: chromate ion and ammonium ion and the process is developed using a
carrier molecule (di-2-ethylhexyl phosphate for ammonium and Aliquat 336 for chromate) in sunflower oil. The removal
percentages are very good (in the range of 43-99%) and obtained at their natural conditions (with no chemical added for
the adjustment of pH) of the aqueous feed. The main attraction of the process is the good performance of sunflower oil,
which can be considered a “green” solvent system as it has the benefit of being environmentally friendly, less costly,
non-toxic and sustainable.

Organic Micropollutant Removal by a Nanofiltration Pilot Plant used to Treat Spring Water from a Wastewater-Irrigated Valley Alma Chávez* Francisco J. Torner

Abstract: The abundance of freshwater springs in the Tula Valley is well documented. Large quantities of untreated
wastewater from Mexico City are used for irrigation purposes, with the resultant emerging springs. Studies are needed to
assess how safe water is to be supplied to the community. Comparative membrane studies were done on lab-scale, from
which NF270 membrane was selected for a pilot plant in situ (critical flux 185Lm-2h-1). The system was successful at
removing natural organic matter, hardness and pathogenic content. On-site membrane pretreatment using microfiltration and
softening allowed moderate recoveries (60%) and slow permeate flux losses (124-90Lm-2h-1). Micropollutant (MP) removal was
greater than 90% for most of the pharmaceuticals, hormones and phthalates using spiked spring water. However,
moderate and variable removals were found when the concentrations of MPs were very low. Molecular structure and
hydrophobicity were loosely related to the removal rates of the compounds evaluated, however an accumulating effect
on the membrane might be key for higher MP removals. A threshold of concentration could have to be overcome to allow the
removal process to achieve a better performance. In consequence, optimization of a large-scale process is the next step to
take.

Hydrogen Production using Solar Membrane Reactor Technology Ali Khosravani Elahe Safaee*

Abstract: Fossil fuels as energy resources are decreasing rapidly which will cause a fuel supply crisis in the future.
Based on the predictions, global energy consumption has been increased significantly and will continue to rise about two
times higher than now till 2050. On the other hand, the extent of the pollutions released from each of the fossil fuels
made too many problems for human’s lives. Thus, the need for new energy sources has increased recently. The need of
affordable and clean alternatives for fossil fuels convinced researchers to test other technologies for energy creation. For
example, electrical energy produced by fuel cells is one of the perfect solutions to decrease environmental pollution due
to its high efficiency, non-environmental pollution and consumption of hydrogen as a clean fuel. Generally hydrogen can
be obtained from various sources such as fossil fuels (natural gas reforming of coal and natural gas), renewable
resources, water electrolysis and etc. Of course, each of these processes has its advantages and disadvantages in
different conditions. The solar reactor membrane technology in recent years has been proposed as an effective way to
produce hydrogen from renewable sources. The purpose of this study is on hydrogen production processes using solar
membrane reactor technology. Therefore, various hydrogen production methods have been proposed and the
advantages and disadvantages of each method have been analyzed. The combination of membrane technology with
solar technology and the developments in solar membrane systems is a good alternative to fossil fuels as a green
process for hydrogen production, which is cost-effective in terms of thermal efficiency and fuel consumption rate.

Removal of Diclofenac from Water using an Hybrid Process Combining Activated Carbon Adsorption and Ultrafiltration or Microfiltration Hassan Abdi Bogoreh Catherine Charcosset*

Abstract: Small amounts of pharmaceuticals are increasingly found in natural waters and wastewaters in treatment
plants. Several processes are developed for their removal such as hybrid membrane processes. These techniques
integrate membrane filtration (mainly ultrafiltration or microfiltration) to a physical technique (such as flocculation or
sorption on activated carbon). In this study, we report results on a process with sorption on activated carbon and
microfiltration or ultrafiltration using a ceramic membrane, with a specific attention to the influence of the membrane pore
size. The membranes showed little fouling at the experimental conditions used (maximum 500 mg/L activated carbon),
while an important increase in conductivity was observed in permeate samples due to the salting out of ions from the
activated carbon particles. Besides, the removal of diclofenac and humic acid (both at 10 mg/L) was higher than 90 %
during the treatment with both ultrafiltration and microfiltration, however microfiltration was preferred due to its higher
flux. These results suggest that hybrid processes of activated carbon/ultrafiltration or microfiltration could be interesting
alternatives for processing waters containing small amounts of pharmaceuticals.

Comparative Study on Composite Electrodes for Medium Temperature PEFC I. Gatto A. Carbone*

Abstract: The purpose of the present study consists in the development of a MEA (Membrane-Electrode-Assembly) for
Polymer Electrolyte Fuel Cells (PEFCs) applications at intermediate temperatures (T>100°C) through the introduction of
inorganic compounds within the catalytic layer of the electrodes. For this aim, composite electrodes containing three
inorganic compounds, with different chemical and physical properties, were developed with percentages ranging
between 0-14 wt% of zeolite H-BETA, titania (TiO2) and yttria stabilized zirconia (YSZ) maintaining the same Platinum
loading of 0.5 mg/cm2 and assembling the electrodes to a commercial N115 membrane. Electrochemical studies in terms
of V-I curves were carried out in a temperature range of 80-130°C in order to select the optimal content of filler.
A comparison between the standard electrode and the best composite electrode containing the optimal amount for each
investigated inorganic material was carried out. The role of inorganic materials is to limit the ionomer swelling by
maintaining the mechanical characteristics of the polymer quite unaltered and to enhance the durability of the
electrocatalyst to degradation phenomena during the fuel cell operation at a temperature over the critical one. For each
inorganic material, a different optimal amount was found to be dependent on their chemical-physical properties, in
particular the particle size, acidity and intrinsic proton conductivity. At high temperature (130°C), the beneficial effect of
oxides introduction is more evident: a reduced cell resistance, a reduced Tafel slope, increased OCV values and
improved fuel cell performance for composite electrodes than the standard one. It was supposed that a limit in the oxide
introduction exists and it depends on physical properties of the inorganic filler, in particular the grain size, the acidity, the
intrinsic proton conductivity and the physical properties of the polymeric matrix used as an ionomer.

Diffusion of C1-C3 Alkanes in Semicrystalline Poly(4-Methyl-1- Pentene) as a Two-Phase Polymeric System S.Y. Markova I.N. Beckman

Abstract: Poly(4-methyl-1-pentene) (PMP) is using up to now as the hollow fiber air separation membranes. This
polymer with good resistance to organics attack can be prospective for separation of lower hydrocarbons.
An attempt for the theoretical consideration and experimental study of the C1-C3 alkanes diffusion in poly(4-methyl-1-
pentene) (PMP) as a binary system in the temperature range from 253,K to 353, K covering the glass transition region of
PMP (~ 303, K) is carried out in this work. The permeability of CH4, C2H6, C3H8 has been measured by the permeability
differential method under the partial pressure drop across the membrane 1 bar with the gas chromatography analysis of
the permeate flux. The diffusion coefficients have been calculated from the experimental differential permeability curves
by using linearization method developed earlier. Novelty of results is that at temperatures below Tg PMP can be
considered as a single-phase system from the gas transfer point of view. At the temperatures above Tg PMP can be
considered as a two-phase medium with diffusion coefficients of C1-C3 alkanes in amorphous (Da) and crystalline phases
(Dc) (Da>Dc) which differ by not more than an one order of magnitude. For the first time it is shown that the diffusivity of
C1-C3 alkanes in amorphous and crystalline PMP phases is decreasing in accordance with sequence DCH4 >DC2H6
>DC3H8. A certain scatter of the PMP data published in the literature was noted. Obtained data can be relatively
compared with published ones only for methane: for virgin PMP films we obtained PCH4 = 16.7 Barrer; it is known for the
extrusion PMP films that PCH4 = 14.6 – 19.8 Barrer, for casted PMP films PCH4 = 0.4 – 1.2 Barrer. The values for ethane
and propane in crystalline phase of PMP are obtained for the first time. Evaluation of permeability through crystalline
phase at temperature 313,K shows that PC2H6 = 15 Barrer; PC3H8 = 5 Barrer. For real estimation of the separation
efficiency PMP it is needed an additional research with taking into account the crystallinity and temperature
dependences for diffusivity based on results of this study.

A Study of High Temperature Mixed Ionic-Electronic Conducting (MIEC) Ceramic Membrane Catalytic Reactor with Single-Step Water-Gas-Shift (WGS) Reaction for Hydrogen Production and Separation Elango Balu J.N. Chung1,*

Abstract: The feasibility of a catalytic reactor made of mixed ionic-electronic conducting (MIEC) ceramic membrane as a
significant option to enhance the production of pure H2 from biomass gasification is established. Thin film
SrCe0.7Zr0.2Eu0.1O3-δ (SCZE) membranes supported by a NiO-SrCe0.8Zr0.2O3-δ (NiO-SCZ) tubular structure were
developed and tested in simulated high-temperature steam gasification conditions. The main advantage of this
membrane reactor design is that it acts as a water gas shift (WGS) reactor for more hydrogen production and
simultaneously separates H2 brought in by the feed gas stream and that produced in the membrane. The current process
avoids the need for a two-stage reactor setup requiring WGS and H2 separation independently. The possibility of
sequestering the isolated pure CO2 stream is also a plus to this membrane reactor.
This paper showcases the experimental analysis of a MIEC ceramic membrane reactor, tested at high temperatures
typically found in biomass high-temperature steam gasification systems. Syngas produced from high-temperature
gasification of biomass is a complex mixture of hydrocarbons and steam. The current experiments conducted using the
tubular SCZE membranes exposed to [CO] and [H2O] vapor at 900°C and 1 atm. showed the feasibility of carrying out
WGS reaction and separating hydrogen thus produced in a single pass at gasifier exit conditions .The process described
in this paper has not been reported previously in the literature. The results show that SCZE membranes can consistently
separate the hydrogen produced by maintaining the integrity of the membrane structure at high temperatures. The
overall reactor system efficiency was estimated to be close to 40%.

Determination of CO2 Absorption Kinetics in Amino Acid Salts Solutions Using Membrane Contactors Rui Afonso Sofia Félix

Abstract: The reaction kinetics of CO2 with amines is usually studied using a stirred-cell reactor. This involves the
construction of a sensitive and cumbersome apparatus, used through a lengthy and complicated experimental
procedure. In this work, the feasibility of using an alternative method is assessed, based on the permeation of CO2
through a membrane contactor into the amine-containing solution. A hollow fibre module of polydimethylsiloxane dense
layer supported on a porous polyetherimide layer was initially tested, but membrane resistance to CO2 permeation was
too large to allow liquid resistance to be dominant, and thus the kinetic parameters of the solution could not be
determined. A membrane with lower resistance was then used, a porous polytetrafluoroethylene (PTFE) flat-sheet
membrane, which did allow for liquid resistance to be dominant, and thus permitted the calculation of kinetic parameters
in the reaction system.
The kinetic constants calculated from the data obtained with the permeation experiments performed with the PTFE
membrane were compared with results reported in the literature. The two sets of results show differences, although the
general concentration dependence trends were similar. Similar differences have previously been observed between
works of different authors, and so the method tested should be considered viable.

Theoritical Study of Various Configurations of Membrane Processes for Olefins Separation K. Ghasemzadeh1,* M. Jafari

Abstract: The major purpose of present study, is investigation of the ZIF-8 membrane performance for various
configurations, namely; single stage, series multistage and countercurrent recycle cascade (CRC), during separation of
propylene from propane and other gases. To this aim, a balck-box model was developed using Pro II software vesion 9
and its validation was carried out by comparing the simulation results with experimental data. The results of simulation
validation illustrated a good agreement between theoritical results and experimental data. After simulation validation, for
propylene separation, various configurations of ZIF-8 membrane process (single stage, series multistage and
countercurrent recycle cascade (CRC) multistage) were compared and the best results were achieved for CRC
configuration. In this work, the influence of the some significant operating parameters, namely pressure gradient, feed
molar flow rate and membrane surface area on the performance of ZIF-8 membrane was studied in term of purification
efficiency of propylene. In general, the simulation results showed that the ZIF-8 membrane presents acceptable
performance to produce high purity propylene. It can be concluded that the propylene composition in the permeate side
was decreased by membrane surface area, while the feed flow rate and pressure gradient effects were different.
However, increasing of feed flow rate indicated the enhancement of propylene molar fraction in retentate side and
consequently this result showed decreasing of the membrane performance

Theoretical Understanding of How Solution Properties Govern Nanofiltration Performances Sébastien Déon1,* Patrick Dutournié

Abstract: Mechanisms governing transfer of ions through nanofiltration membranes are complex and it is primordial to
understand how rejection and selectivity performances depend on the properties of the solution. For this purpose, a
knowledge model based on a coupling between equilibrium partitioning induced by steric, electric and dielectric
exclusions and transport inside pores by diffusion, convection and electro-migration is proposed to theoretically discuss
the influence of solution properties on performances. After detailing the physical description of this model, the influence
of ion size on rejection is firstly discussed from simulations obtained in several appropriate cases. Since electrostatic
interactions are known to play a role on ion rejection, the influence of ion valence and concentration is then studied and
different behaviors are brought to light depending on ions considered. Finally, the influence of confinement within
nanopores on water dielectric properties and its consequences for ion separation are also addressed.

A Heat Exchanger Reactor Equipped with Membranes to Produce Dimethyl Ether from Syngas and Methyl Formate and Hydrogen from Methanol A. Bakhtyari A. Darvishi

Abstract: The energy crisis of the century is a motivation to present processes with higher energy efficiency for
production of clean and renewable resources of energy. Hence, a catalytic heat exchanger reactor for production of
dimethyl ether (DME) from syngas, and hydrogen and methyl formate (MF) from methanol is investigated in the present
study. The proposed configuration is equipped with two different membranes for in-situ separation of products. Syngas is
converted to DME through an exothermic reaction and it supplies a part of required energy for the methanol
dehydrogenation reaction. Produced water in the exothermic side and produced hydrogen in the endothermic side are
separated by using appropriate perm-selective membranes. In-situ separation of products makes the equilibrium
reactions proceed toward higher conversion of reactants. A mathematical model based on reasonable assumptions is
developed to evaluate molar and thermal behavior of the configuration. Performance of the system is aimed to enhance
by obtaining optimum operating conditions. In this regard, Genetic Algorithm is applied. Performance of the heat
exchanger double membrane reactor working under optimum conditions (OTMHR) is compared with a heat exchanger
reactor without membrane (THR). OTMHR promotes methanol conversion to MF to %87.2, carbon monoxide conversion
to %95.8 and hydrogen conversion to %64.6.

On the Relationship between the Permeability Parameters of Gases and Vapors of C1-C4 Aliphatic Alcohols in Hydrophobic Polymeric Membranes A. A. Kozlova M.G. Shalygin

Abstract: A correlation approach for the evaluation of permeability, diffusion and solubility coefficients of lower aliphatic
alcohols in polymeric membranes using basic parameters of gas transfer is proposed in this work. Previously published
results of experimental study of water, ethanol and n-butanol vapors transfer in hydrophobic membranes based on
glassy polymers as well as obtained new experimental data on vapor permeability of methanol, n-propanol and gases
were critically reviewed. An attempt to demonstrate correlation of selective gas and vapor transfer parameters of
membranes is made in the present study. The establishment of correlation of permeability of gases and C1-C4 aliphatic
alcohols vapors in hydrophobic polymeric membranes allows to use available methods and data of gas transfer
characteristics of membrane materials and membranes for estimation of the vapor separation properties, e.g., modern
Data Base for gas permeability parameters of polymers can be used for evaluation of the membrane separation potential
in relation to lower aliphatic alcohols. The hydrophobic polymers were selected in order to avoid specific interactions
between alcohols and polymer (such as strong induction, dipole-dipole interactions and H-bond creation). Results
include a preliminary estimation of diffusion coefficients of water and C1-C4 alcohols vapors on the basis of correlation
analysis that was previously proposed for the estimation of gas transport parameters. The proposed approach allows to
explain the observed characteristics of the mentioned vapors permeability in polymeric membranes and to show new
relations of gases and vapors transfer in membranes. It seems that obtained results will be useful for the development of
vapor-phase membrane methods of organic substances separation.

Effect of Mass Transfer Resistance of Polymeric Surfactant on Transport of Metal through Bulk Liquid Membrane Interface Diptendu Das Nil

Abstract: This research work deals with an investigation on the reduction of mass transfer coefficient due to the
presence of polymeric surfactant/ polycondensate layer in the liquid membrane. Mo(VI) is chosen as target species
which are to be removed from feed solution using Bulk Liquid membrane (BLM) in presence of polymeric surfactant and
extractant. Mathematical model is developed for simulation of kinetics of Mo(VI) extraction using BLM. Study reveals that
for efficient Mo(VI) extraction, reduction of stripping rate is not at all desirable. Abil EM 90 is found best suitable
polymeric surfactant as it has least mass transfer resistance of Mo(VI) transport in strip phase. This study is very useful
for selecting suitable polymeric surfactant/ polycondensate layer for stabilising liquid emulsion membrane for metal
extraction/recovery purpose.

Assessment of the SEDE Model: Determination of Membrane Potential and Salt Rejection of a Nanofiltration Membrane Yannick Lanteri Anthony Szymczyk

Abstract: Up to now, the SEDE (Steric Electric and Dielectric Exclusion) model was used to describe solute rejection in
nanofiltration or membrane potential measurements. This model uses four fitting parameters: pore size, thickness to
membrane porosity ratio, volume charge density (X) and dielectric constant of the solution inside pores (εp). Because
these two latter parameters are extremely difficult to measure, an alternative method for assessing the SEDE model was
to study both salt rejections and membrane potentials for a same salt. Experiments were conducted with a NF polyamide
membrane in CaCl2 solutions. In the case of single salt solutions, experimental rejections and membrane potentials can
be described by a number of couples (X, εp) because both electric and dielectric exclusion contribute to reject ions. Only,
one of the couples was found to provide a good description of both experimental rejections and membrane potentials.
The fact that a unique choice for X and εp allows accounting simultaneously for both the salt rejection and the membrane
potential data is an indicator of the global coherence of the SEDE model.

A Review on Membranes for Clinical Treatment and Drug Delivery in Medical Applications Catherine Charcosset* Nil

Abstract: Membrane processes are used extensively in biomedical applications. This state of the art review presents the
main applications including renal kidney, blood filtration, blood oxygenator, artificial liver, artificial pancreas, and drug
delivery devices. For well-established treatments like dialysis, plasmapheresis, and blood oxygenator, the techniques are
summarized by presenting membranes used, devices, configurations and treatments. The artificial liver and the artificial
pancreas are not clinically used and some main aspects related to the development of these devices are given, including
configurations and liver or pancreatic cells. Finally, drug delivery devices based on membranes, which are an important
area in pharmaceutics, are summarized by focusing on diffusion and transdermal delivery systems, as well as colloids
like liposomes and nanocapsules. These colloids with nanometric size are surrounded by a lipidic or polymeric thin
membrane which controls drug transfer to the surrounding medium.

Theoretical Considerations of Pressure Drop and Mass Transfer of Gas Flow in Spiral Wound Membrane Modules M. Metaiche J. Sanchez-Marcano*

Abstract: In this work we give the preliminary results of the development of two reliable correlations for the calculation of
the friction and mass transfer coefficients for the gas transfer through spiral wound membrane modules. The mass
transfer coefficient which allows determining the polarization phenomenon was taken in consideration through the
calculation of the Sherwood number near the surface of the membranes. Both correlations take in consideration the
inclination angle of transversal and longitudinal filaments of grids in spacers. They allow a good prediction of the
pressure drop, friction coefficient and the mass transfer in spiral modules for gas flow when compared with experimental
results obtained in a previous work reported in the literature.

Hybridization of Advanced Oxidation Processes with Membrane Separation for Treatment and Reuse of Industrial Laundry Wastewater Sylwia Mozia Magdalena Janus

Abstract: A new attempt to treat and reuse the industrial laundry wastewater using biological treatment followed by
advanced oxidation processes (AOPs) and membrane separation is presented. Three various configurations of the
hybrid systems were investigated: (1) biological treatment in a Moving Bed Biofilm Reactor (MBBR) – photocatalysis with
suspended TiO2 P25, enhanced with in situ generated O3 – ultrafiltration (UF) – nanofiltration (NF); (2) biological
treatment in MBBR– photocatalysis with immobilized TiO2 P25, enhanced with in situ generated O3 – UF - NF; (3)
biological treatment in MBBR – photolysis/ozonation (with in situ generated O3) – UF – NF. For comparison purpose the
wastewater was additionally treated in the MBBR – UF – NF mode (4). Application of AOPs contributed to the UF
membrane fouling mitigation during treatment of the biologically pretreated laundry wastewater. The highest
improvement of the UF permeate flux was found in case of the MBBR effluent treated with application of the immobilized
TiO2 bed which was attributed to the highest efficiency of mineralization observed for that system. Since the applied
wastewater contained significant amounts of inorganic ions, mainly Na+ and Cl-, the NF as the final polishing step was
proposed. The quality of NF permeate was independent on the AOP mode applied and, moreover, significantly higher
than the quality of water currently used in the laundry. It was concluded that the NF permeate could be recycled to any
stage of the laundry system. Taking into consideration that application of TiO2 increases the overall treatment costs and
that although the O3/UV pretreatment is less efficient than photocatalysis, it still allows to improve the UF permeate flux
for ca. 35% compared to the direct UF of the MBBR effluent, the MBBR – UV/O3 – UF – NF system was proposed as the
most beneficial configuration for the treatment and reuse of the industrial laundry wastewate

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