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Applicability Of Fluidized Bed Reactor In Recalcitrant Compound Degradation Through Advanced Oxidation Processes: A Review, Abdul Aziz Abdul Raman Dec 2014

Applicability Of Fluidized Bed Reactor In Recalcitrant Compound Degradation Through Advanced Oxidation Processes: A Review, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

Treatment of industrial waste water (e.g. textile waste water, phenol waste water, pharmaceutical etc) faces limitation in conventional treatment procedures. Advanced oxidation processes (AOPs) do not suffer from the limits of conventional treatment processes and consequently degrade toxic pollutants more efficiently. Complexity is faced in eradicating the restrictions of AOPs such as sludge formation, toxic intermediates formation and high requirement for oxidants. Increased mass-transfer in AOPs is an alternate solution to this problem. AOPs combined with Fluidized bed reactor (FBR) can be a potential choice compared to fixed bed or moving bed reactor, as AOP catalysts life-span last for only …


Electrochemically Active Biofilm Assisted Synthesis Of Ag@Ceo2 Nanocomposites For Antimicrobial Activity, Photocatalysis And Photoelectrodes, Mohammad Mansoob Khan Dr, S. A. Ansari, J. H. Lee, M. O. Ansari, J Lee, M. H. Cho Sep 2014

Electrochemically Active Biofilm Assisted Synthesis Of Ag@Ceo2 Nanocomposites For Antimicrobial Activity, Photocatalysis And Photoelectrodes, Mohammad Mansoob Khan Dr, S. A. Ansari, J. H. Lee, M. O. Ansari, J Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Ag@CeO2 nanocomposites were synthesized by a biogenic and green approach using electrochemically active biofilms (EABs) as a reducing tool. The as-synthesized Ag@CeO2 nanocomposites were characterized and used in antimicrobial, visible light photocatalytic and photoelectrode studies. The Ag@CeO2 nanocomposites showed effective and efficient bactericidal activities and survival test against Escherichia coli O157:H7, and Pseudomonas aeruginosa. The as-synthesized Ag@CeO2 nanocomposites also exhibited enhanced visible light photocatalytic degradation of 4-nitrophenol and methylene blue than pure CeO2. A photocatalytic investigation showed that the Ag@CeO2 nanocomposites possessed excellent visible light photocatalytic activities compared to pure CeO2. Electrochemical impedance spectroscopy and photocurrent measurements showed that the …


Makha – A New Hybrid Stochastic Optimization Method For Phase Equilibrium Calculations, Seif-Eddeen K. Fateen, Ahmed M. Khalil, Ragab K. Abdel-Magied Aug 2014

Makha – A New Hybrid Stochastic Optimization Method For Phase Equilibrium Calculations, Seif-Eddeen K. Fateen, Ahmed M. Khalil, Ragab K. Abdel-Magied

Seif-Eddeen K Fateen

No abstract provided.


Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho Aug 2014

Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Au@TiO2 nanocomposites were used for the catalytic degradation of methyl orange and methylene blue by NaBH4. A detail pathway for step by step reduction, oxidation and complete mineralization of intermediates into the respective end-products was established by UV-vis spectroscopy, chemical oxygen demand, ion chromatography and cyclic voltammetry (CV). CV studies confirmed that the dyes were reduced and oxidized to the end-products by NaBH4 in the presence of Au@TiO2 nanocomposites and O2•, •OH and HO2• radicals generated in-situ. Results suggest that Au@TiO2 nanocomposites not only assist in the decolorization of dyes, but also promote their complete mineralization into harmless end-products.


Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho Aug 2014

Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Highly visible light active 1% and 3% Ag@ZnO nanocomposites were synthesized via a gel combustion route using citric acid as a fuel. The formation of the nanocomposites with enhanced properties was confirmed using a range of characterization techniques, photocatalysis and photoelectrochemical studies. Compared to the pristine ZnO nanoparticles, the Ag@ZnO nanocomposites exhibited enhanced visible light photocatalytic activity for the degradation of methylene blue and photoelectrochemical response. A mechanism was proposed to account for the photocatalytic activities of the Ag@ZnO nanocomposite that showed the surface plasmon resonance (SPR) of Ag is an effective way of enhancing the visible light photocatalytic activities.


Investigation Of Convection And Diffusion During Biodiesel Production In Packed Membrane Reactor Using 3d Simulation, Abdul Aziz Abdul Raman Jul 2014

Investigation Of Convection And Diffusion During Biodiesel Production In Packed Membrane Reactor Using 3d Simulation, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

The 3D simulation of convection and diffusion phenomena within a ceramic membrane during transesterification reaction was the aim of this study. The ceramic membrane was a tubular micro porous TiO2/Al2O3 packed with the heterogeneous catalyst. The Navier-Stokes, Brinkman and Stephan-Maxwell equations were applied for investigation of fluid flow reaction and mass transfer within the system. The value of the convection was generally between 104 and 107 times higher than diffusion. It depends on concentration component, the diffusion coefficient and components velocity. A good agreement was found with the maximum deviation of 8% from experimental data. © 2013 The Korean Society …


A Molecular Dynamics Simulation Of The Stability-Limited Growth Mechanism Of Peptide-Mediated Gold-Nanoparticle Synthesis, Jing Yu, Matthew Becker, Gustavo Carri Jul 2014

A Molecular Dynamics Simulation Of The Stability-Limited Growth Mechanism Of Peptide-Mediated Gold-Nanoparticle Synthesis, Jing Yu, Matthew Becker, Gustavo Carri

Gustavo A. Carri

The bindingof a 12-residue peptide to a Au {111} surface and nanoparticles with different sizes result in various equilibrium structures and stabilities due to the surface morphology. The equilibrium structures are represented by the distance of peptide atoms to Au surface and the stabilities of peptide residues are represented by the average change of dihedral angles.


Sulfonated Polystyrene Ionomers Prepared By Emulsion Copolymerization Of Styrene And Sodium Styrene Sulfonate, Robert Weiss Jul 2014

Sulfonated Polystyrene Ionomers Prepared By Emulsion Copolymerization Of Styrene And Sodium Styrene Sulfonate, Robert Weiss

Robert Weiss

Sulfonated polystyrene (S–PS), which is of considerable scientific and technological interest, has been traditionally prepared by the sulfonation of preformed polystyrene. This report describes the preparation and properties of S–PS prepared by emulsion copolymerization of styrene and sodium styrene sulfonate. S–PS prepared by copolymerization gave solubility, solution behavior and thermal characteristics that are consistent with an ionomeric structure. The solubility characteristics indicated some chain-to-chain sulfonate heterogeneity. Thermal analysis studies indicated that the glass transition does not increase with increasing sulfonate content. This is contrary to what has been observed for S–PS prepared by sulfonation and suggests that the S–PS prepared …


Development Of An Ionomer Tracer For Extruder Residence Time Distribution Experiments, Robert Weiss Jul 2014

Development Of An Ionomer Tracer For Extruder Residence Time Distribution Experiments, Robert Weiss

Robert Weiss

A polymeric tracer was developed from the tributylamine salt of lightly sulfonated polystyrene. The residence time distribution (RTD) measured for the extrusion of polystyrene with this tracer was compared with that measured using conventional particulate tracers, In general, the particulate tracers had a longer mean residence time and a broader RTD, which were attributed to increased mixing of the particulates.


Small Angle X-Ray Scattering Studies Of Zinc Stearate Filled Sulfonated Epdm, D. A. Jackson, J. T. Koberstein, Robert Weiss Jul 2014

Small Angle X-Ray Scattering Studies Of Zinc Stearate Filled Sulfonated Epdm, D. A. Jackson, J. T. Koberstein, Robert Weiss

Robert Weiss

The crystallization, melting, and dissolution behavior of zinc stearate (ZnSt) in ZnSt-filled sulfonated poly(ethylene-co-propylene-co-ethylidene norbornene) (SEPDM) ionomers was studied by synchrotron small-angle X-ray scattering (SAXS). The melting temperature of ZnSt in the ionomer was considerably lower than in the pure state, which was consistent with the existence of very small ZnSt crystalline domains and a specific interaction between the metal sulfonate groups of the SEPDM and the metal carboxylate groups of ZnSt. Temperature-resolved SAXS showed that, on melting, some or all of the ZnSt rapidly dissolved into the ionomer. Ionic aggregates in the neat ionomer persisted up to 300°C. Microphase …


Morphology Development In Polymer Blends Exhibiting Strong Intermolecular Interactions, Robert Weiss, Y. Feng, C. C. Han, A. Karim Jul 2014

Morphology Development In Polymer Blends Exhibiting Strong Intermolecular Interactions, Robert Weiss, Y. Feng, C. C. Han, A. Karim

Robert Weiss

He et al. measured the spinodal decomposition (SD) kinetics of a blend of poly(butyl methacrylate) with a polystyrene modified with 1.5 mol% of a hydroxy-containing comonomer that exhibited intermolecular hydrogen bonding, who studied blends. For small excursions into the spinodal region, multiple structures developed in the blend, which suggested that multiple mechanisms may be involved in the phase separation process. For most cases, however, the kinetics of phase separation followed Cahn-Hilliard theory in the early stage of spinodal decomposition and a self-similar mechanism in the later stages, similar to non-associating polymer blends such as PS/PVME. The failure to observe an …


Microphase Separation In Sulfonated Polystyrene Ionomers, Robert Weiss Jul 2014

Microphase Separation In Sulfonated Polystyrene Ionomers, Robert Weiss

Robert Weiss

Small- and wide-angle x-ray scattering results for a series of un-neutralized and neutralized sulfonated polystyrenes are presented for the range of sulfonation from 0 to 7.26 mol %. From the small-angle scattering it is shown that above the 3 mol % level for both the zinc and sodium salts, a Bragg spacing (37 Å) and diameter (6.9–8.4 Å) of the scattering unit can be calculated. When the concentration of salt is increased, there is no appreciable change in the latter two measurements. The wide-angle data indicate that the cations do not influence to any large extent the basic intramolecular and …


Effect Of Solvents On The Microstructure Of Sulfonated Polystyrene Ionomers, Robert Weiss, J. J. Fitzgerald, D. Kim Jul 2014

Effect Of Solvents On The Microstructure Of Sulfonated Polystyrene Ionomers, Robert Weiss, J. J. Fitzgerald, D. Kim

Robert Weiss

No abstract provided.


Characterization Of Blends Of An Amorphous Polyamide With Lightly Sulfonated Polystyrene Ionomers, Robert Weiss Jul 2014

Characterization Of Blends Of An Amorphous Polyamide With Lightly Sulfonated Polystyrene Ionomers, Robert Weiss

Robert Weiss

Improved compatibility of blends of polystyrene and an amorphous polyamide was achieved by lightly sulfonating the polystyrene. Hydrogen bonding between amide groups and either sulfonic acid or metal sulfonate groups lowered the interfacial tension between the two polymers, which led to a much finer dispersed phase size in blends involving the sulfonated polystyrene. At relatively high sulfonate to amide ratios, the two polymers formed a miscible blend. Improved mixing of the phases was verified by shifts in the glass transitions, and the specific interactions that occurred were characterized by Fourier transform infrared spectroscopy.


Flow-Induced Phase Changes Of Ps/Pib Blends, R. Wu, M. T. Shaw, Robert Weiss Jul 2014

Flow-Induced Phase Changes Of Ps/Pib Blends, R. Wu, M. T. Shaw, Robert Weiss

Robert Weiss

No abstract provided.


The Effects Of Low Molar Mass Diluents On The Microstructure Of Ionomers, Robert Weiss Jul 2014

The Effects Of Low Molar Mass Diluents On The Microstructure Of Ionomers, Robert Weiss

Robert Weiss

The effect of polar and nonpolar low molar mass diluents on the microstructure of lightly sulfonated polystyrene (SPS) ionomers was studied using electron spin resonance spectroscopy, small-angle x-ray scattering, and dynamic mechanical analysis. Nonpolar diluents primarily affected the hydrocarbon - rich phase, while polar diluents partitioned into the ion-rich regions and disrupted the supramolecular structure. The ionic clusters remained intact, even at elevated temperatures, upon the addition of nonpolar solvents such as dodecane and dioctylphthalate. More polar solvents such as methanol and glycerol swelled the ionic domains and promoted increased mixing of the two phases.


Phase Behavior And Specific Interactions Of Blends Of Nylon 6 And Sulfonated Polystyrene Ionomers., X. Lu, Robert Weiss, T. K. Kwei, Y. K. Dai Jul 2014

Phase Behavior And Specific Interactions Of Blends Of Nylon 6 And Sulfonated Polystyrene Ionomers., X. Lu, Robert Weiss, T. K. Kwei, Y. K. Dai

Robert Weiss

No abstract provided.


Studies On A Diphenylether Modified Poly(Phenyl-1,4-Phenylene Terephthalate) Liquid Crystalline Polymer And Its Blends With Polycarbonate And Polysulfone, Robert Weiss Jul 2014

Studies On A Diphenylether Modified Poly(Phenyl-1,4-Phenylene Terephthalate) Liquid Crystalline Polymer And Its Blends With Polycarbonate And Polysulfone, Robert Weiss

Robert Weiss

Blends of a thermotropic liquid crystalline polymer, LCP, (4,4′-dicarboxy diphenyl ether modified poly(phenyl-1,4-phenylene terephthalate)) with polycarbonate and polysulfone were prepared and characterized with respect to their thermal properties, viscoelastic behavior, processability and mechanical properties. The processability of the thermoplastics was significantly improved by the addition of small amounts of LCP. This was also reflected by decreases in the steady shear viscosities, though the dynamic complex viscosities of the blends were generally similar or higher than those of the individual component polymers. Composite fibers were spun from the blends and the tensile moduli and strengths were consistent with a morphology of …


Strain Induced Crystallization Of Peek, Robert Weiss Jul 2014

Strain Induced Crystallization Of Peek, Robert Weiss

Robert Weiss

Strain-induced crystallization of poly(ether ether ketone) (PEEK) was studied by the use of a parallel plate rheometer. The experimental variables included preheating time, crystallization temperature, and shear rate. The crystallization kinetics were characterized by means of an induction time defined as the time elapsed from the start of shearing to the onset of crystallization. The experimental results showed that the induction time for strain-induced crystallization of PEEK was significantly shorter than that for crystallization under quiescent condition, and that strain-induced crystallization was much less temperature dependent than quiescent crystallization. The activation energy for strain-induced crystallization was found to be 0.035kcal/mole, …


Properties Of Polyethylene Modified With Phosphonate Side Groups I. Thermal And Mechanical Properties, Robert Weiss Jul 2014

Properties Of Polyethylene Modified With Phosphonate Side Groups I. Thermal And Mechanical Properties, Robert Weiss

Robert Weiss

Low-density polyethylene was modified by the inclusion of phosphonate ester pendent groups by using an oxidative chlorophosphonylation reaction followed by esterification of the polyethylene poly(phosphonyl chloride) with an alcohol. Two different types of phosphonate esters were prepared: dimethyl phosphonate from the reaction with methanol and a phosphonate graft copolymer from the reaction with hydroxy-terminated poly(ethylene oxide) (PEO). For the latter, oligomers with molecular weights of 350 and 750 were used. For each type of phosphonate, a series of polymers were prepared with pendent group concentrations ranging from 0 to 9.1 substituents per 100 carbon atoms. The modified polymers were characterized …


Molecular Dynamics Simulation Of Chain Collapse Of Random Ionomers In A Poor Solvent, Robert Weiss, Rue Xie Jul 2014

Molecular Dynamics Simulation Of Chain Collapse Of Random Ionomers In A Poor Solvent, Robert Weiss, Rue Xie

Robert Weiss

Chain collapse and ionic aggregation of sodium salts of lightly sulphonated polystyrene (Na-SPS) in a poor solvent were simulated by molecular dynamics of a single ionomer chain in vacuum. Ionomers with a sulphonation level from 0 to 28 mol% and a polymerisation index of 50 were constructed by virtual copolymerisation of the ionic and nonionic species. Chain collapse occurred by a three-stage process. Local collapse of the ionomer occurred in the first stage, which was marked by sharp decreases in both the radius of gyration (Rg) and the chain end-to-end distance (D). The second stage was a transition to a …


Flow-Induced Structures Of Polybutadiene/Polyisoprene Blends, Z. J. Chen, N. G. Remediakis, M. T. Shaw, Robert Weiss Jul 2014

Flow-Induced Structures Of Polybutadiene/Polyisoprene Blends, Z. J. Chen, N. G. Remediakis, M. T. Shaw, Robert Weiss

Robert Weiss

No abstract provided.


The Control Of The Melt Rheology And Physical Properties Of Polystyrene By Ionic Interaction, Robert Weiss, P. K. Agarwal, R. D. Lundberg Jul 2014

The Control Of The Melt Rheology And Physical Properties Of Polystyrene By Ionic Interaction, Robert Weiss, P. K. Agarwal, R. D. Lundberg

Robert Weiss

No abstract provided.


The Influence Of Intermolecular Interactions On The Melt Rheology Of A Propylene-Acrylic Acid Copolymer And Its Salts., Robert Weiss Jul 2014

The Influence Of Intermolecular Interactions On The Melt Rheology Of A Propylene-Acrylic Acid Copolymer And Its Salts., Robert Weiss

Robert Weiss

Ionomers based on propylene–acrylic acid copolymer have been prepared and their rheological behavior studied. With different cations the melt viscosity at any shear rate increases as tributylamine salt < acid < zinc salt < sodium salt. Similarly, the activation energies for viscous flow follow the order polypropylene ∼ tributylamine salt < acid ∼ zinc salt < sodium salt. These results are a consequence of intermolecular interactions between salt groups for the metal acrylate derivatives and hydrogen bonding for the acid derivatives. Strong ionic interactions are absent in the tributylamine salt because of steric hindrance of the bulky amine substituents. The glass transition temperatures for these …


The Synthesis Of Sulfonated Polymers By Free Radical Copolymerization. (Poly(Butadiene-Co-Sodium Styrene Sulfonate)., Robert Weiss Jul 2014

The Synthesis Of Sulfonated Polymers By Free Radical Copolymerization. (Poly(Butadiene-Co-Sodium Styrene Sulfonate)., Robert Weiss

Robert Weiss

The copolymerization of butadiene with sodium styrene sulfonate was studied and the copolymer products characterized. In general these copolymers contain 0.5–4 mole% of sulfonated monomer. The effects of the following reaction variables are described: emulsifier type and concentration, monomers feed ratio, chain transfer agent concentration, and reaction conversion. The products were heterogeneous with regard to composition, molecular weight, and solubility behavior. Copolymers prepared under certain conditions exhibited strong intermolecular interactions derived from associations of the ionic species as observed in other ionomers.


Improvement Of The Processability Of Poly(Ether Ketone Ketone) By The Addition Of A Liquid Crystalline Polymer, Robert Weiss Jul 2014

Improvement Of The Processability Of Poly(Ether Ketone Ketone) By The Addition Of A Liquid Crystalline Polymer, Robert Weiss

Robert Weiss

The addition of a thermotropic liquid crystalline, wholly aromatic copolyester, TLCP, improved the melt processability of poly(ether ketone ketone), PEKK. The tensile strength and modulus of the blends also improved with increasing TLCP, but the elongation at break decreased significantly. The blends were phase-separated, but the polymers were partially miscible as evident from shifts of the glass transition temperature (Tg) of each component towards that of the other component in the blend. Similarly, the melting points (Tm) of both components were depressed by blending. When the crystallization temperature was above Tm of the TLCP, the PEKK crystallization rate in the …


Synthesis, Properties, And Structure Of Sulfonate Ionomers, Robert Weiss Jul 2014

Synthesis, Properties, And Structure Of Sulfonate Ionomers, Robert Weiss

Robert Weiss

The unique mechanical and rheological properties of ionomers are sources of growing academic and industrial interest. The relationship between the complex properties that ionomers exhibit and their microstructure has been the subject of numerous studies. A greater understanding of this relationship is necessary if one wishes to manipulate the ionic interactions in order to control the properties of the polymer.


Compatibilization Of Syndiotactic Polystyrene And A Thermotropic Liquid Crystalline Polymer Blend With A Zinc Salt Of A Sulfonated Polystyrene Ionomer, Robert Weiss Jul 2014

Compatibilization Of Syndiotactic Polystyrene And A Thermotropic Liquid Crystalline Polymer Blend With A Zinc Salt Of A Sulfonated Polystyrene Ionomer, Robert Weiss

Robert Weiss

A zinc salt of a lightly sulfonated (4.5 mol %) polystyrene ionomer was used to compatibilize a 3/1 (w/w) blend of syndiotactic polystyrene and a wholly aromatic thermotropic liquid-crystalline polymer (TLCP). The addition of the ionomer significantly reduced the dispersed TLCP domain size and improved the tensile strength, ultimate elongation, and flexural toughness of the blend


Microstructure Of Block Copolymers Of Polystyrene And Poly(Ethylene-Alt-Propylene), Robert Weiss Jul 2014

Microstructure Of Block Copolymers Of Polystyrene And Poly(Ethylene-Alt-Propylene), Robert Weiss

Robert Weiss

The microstructure and microphase behaviour of diblock (Ma ≈ 27 and 50 kg mol−1) and triblock (Ma ≈ 50kg mol−1) copolymers of polystyrene (PS) and poly(ethylene-alt-propylene) (PEP) were studied by small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and dynamic mechanical thermal analysis (DMTA). The composition was varied from 10 wt.% to 50 wt.% PS. The morphology of solution-cast and compression-moulded samples was compared. The common packing arrangements of body-centred-cubic (BCC) spheres, hexagonal-close-packed (HCP) cylinders and alternating lamellae were observed for the PS microdomains using SAXS and TEM. A microphase texture of PS spheres with a liquid-like packing (LLP) …


Analysis Of Caprolactam Polymerization, Robert Weiss Jul 2014

Analysis Of Caprolactam Polymerization, Robert Weiss

Robert Weiss

No abstract provided.