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Articles 1 - 30 of 102
Full-Text Articles in Biochemical and Biomolecular Engineering
Immobilization Of The Influenza A M2 Transmembrane Peptide In Virus Envelope−Mimetic Lipid Membranes: A Solid-State Nmr Investigation, Wenbin Luo, Sarah D. Cady, Mei Hong
Immobilization Of The Influenza A M2 Transmembrane Peptide In Virus Envelope−Mimetic Lipid Membranes: A Solid-State Nmr Investigation, Wenbin Luo, Sarah D. Cady, Mei Hong
Sarah Cady
The dynamic and structural properties of membrane proteins are intimately affected by the lipid bilayer. One property of membrane proteins is uniaxial rotational diffusion, which depends on the membrane viscosity and thickness. This rotational diffusion is readily manifested in solid-state NMR spectra as characteristic line shapes and temperature-dependent line narrowing or broadening. We show here that this whole-body uniaxial diffusion is suppressed in lipid bilayers mimicking the composition of eukaryotic cell membranes, which are rich in cholesterol and sphingomyelin. We demonstrate this membrane-induced immobilization on the transmembrane peptide of the influenza A M2 (AM2-TM) proton channel protein. At physiological temperature, …
Stress Response To Co2 Deprivation By Arabidopsis Thaliana In Plant Cultures, Souvik Banerjee, Oskar Siemianowski, Meiling Liu, Kara R. Lind, Xinchun Tian, Dan Nettleton, Ludovico Cademartiri
Stress Response To Co2 Deprivation By Arabidopsis Thaliana In Plant Cultures, Souvik Banerjee, Oskar Siemianowski, Meiling Liu, Kara R. Lind, Xinchun Tian, Dan Nettleton, Ludovico Cademartiri
Dan Nettleton
After being the standard plant propagation protocol for decades, cultures of Arabidopsis thaliana sealed with Parafilm remain common today out of practicality, habit, or necessity (as in co-cultures with microorganisms). Regardless of concerns over the aeration of these cultures, no investigation has explored the CO2 transport inside these cultures and its effect on the plants. Thereby, it was impossible to assess whether Parafilm-seals used today or in thousands of older papers in the literature constitute a treatment, and whether this treatment could potentially affect the study of other treatments.For the first time we report the CO2concentrations in Parafilm-sealed cultures of …
Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge
Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge
Rebecca Ong
Background Heterogeneity within herbaceous biomass can present important challenges for processing feedstocks to cellulosic biofuels. Alterations to cell wall composition and organization during plant growth represent major contributions to heterogeneity within a single species or cultivar. To address this challenge, the focus of this study was to characterize the relationship between composition and properties of the plant cell wall and cell wall response to deconstruction by NaOH pretreatment and enzymatic hydrolysis for anatomical fractions (stem internodes, leaf sheaths, and leaf blades) within switchgrass at various tissue maturities as assessed by differing internode. Results Substantial differences in both cell wall composition …
Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu
Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu
Sarwan S. Sandhu
In industry there are many examples of absorption of a gas with or without chemical reaction in the liquid phase. In physical absorption, a particular gaseous component is removed from a gas mixture due to its larger solubility in the liquid phase solvent. The removal of butane and pentane from a refinery gas mixture by a heavy oil in the liquid phase is an example of physical absorption. In absorption with chemical reaction, the gaseous component to be removed transfers across the gas-liquid interface due to a difference in the bulk chemical potentials or concentrations in the two phases. The …
Evaluation Of Effective Operational Cycle Time And Bioprocess Parameters In A Sequential Batch Reactor For Efficient Organic And Nutrient Removal From Domestic Sewage, Sandip S. Magdum, Siva Kumar Varigala, Yogesh N. Patil, Gauri P. Minde, Janardhan B. Bornare, V. Kalyanraman
Evaluation Of Effective Operational Cycle Time And Bioprocess Parameters In A Sequential Batch Reactor For Efficient Organic And Nutrient Removal From Domestic Sewage, Sandip S. Magdum, Siva Kumar Varigala, Yogesh N. Patil, Gauri P. Minde, Janardhan B. Bornare, V. Kalyanraman
Sandip S. Magdum
Anaerobic, anoxic and aerobic environment can be simulated in the single stage sequential batch reactor (SBR) . Various design conditions viz., combinations of different phase time and different cycle time, hydraulic residence time (HRT), substrate loading rate, sludge age (SRT) and aeration time were analyzed for optimum biological treatment. The pilot runs were evaluated with the design conditions of food/microbe ratio (F/M) 0.2 per day and MLSS of 4950 mg/L. For the given design conditions 4, 5 and 6 hours cycle lengths were analyzed for their efficient performance with 30-33% of decant volume for sewage containing C:N:P of 100:8:2. Studies …
Proceedings Of The Thirty-Second Annual Biochemical Engineering Symposium, Peter J. Reilly
Proceedings Of The Thirty-Second Annual Biochemical Engineering Symposium, Peter J. Reilly
Peter R. Reilly
This series of Annual Biochemical Engineering Symposia was started in 1971 by Professors Larry E. Erickson of Kansas State University and Peter J. Reilly, then of the University of Nebraska-Lincoln. It is designed for graduate students and occasionally postdoctoral fellows and undergraduates to present the results of their research and directions of their future work to audiences not so familiar as those at their home institutions but not so seemingly intimidating as those at national professional meetings. It also serves as a vehicle for those engaged in similar lines of research to become acquainted with each other and with each …
Competence Evaluation Of Mycodiesel Production By Oleaginous Fungal Strains: Mucor Circinelloides And Gliocladium Roseum, Sandip S. Magdum, Gauri P. Minde, Upendra S. Adhyapak, V. Kalyanraman
Competence Evaluation Of Mycodiesel Production By Oleaginous Fungal Strains: Mucor Circinelloides And Gliocladium Roseum, Sandip S. Magdum, Gauri P. Minde, Upendra S. Adhyapak, V. Kalyanraman
Sandip S. Magdum
Comparing with lesser algal growth rate for biofuel production along with many constraints, fungal route should be analyzed for its capability of biodiesel or mycodiesel production. The two fungal strains namely, Mucor circinelloides (MTCC1297) and Gliocladium roseum (MTCC6474) were analyzed for laboratory scale mycodiesel production. The M. circinelloides and G. roseum were able to produce biomass of 0.404 mg VSS/mg sucrose and 0.642 mg VSS/ mg sucrose with the mycodiesel content of 20.69% (w/w) and 11.37% (w/w) respectively. Furthermore, qualitative analysis of the oil contents by GC-MS were identified the presence of Tetradecanoic and Octadecanoic acids.
Evaluation Of Sequential Batch Reactor (Sbr) Cycle Design To Observe The Advantages Of Selector Phase Biology To Achieve Maximum Nutrient Removal, Sandip S. Magdum, Siva Kumar Varigala, Gauri P. Minde, Janardhan B. Bornare, V. Kalyanraman
Evaluation Of Sequential Batch Reactor (Sbr) Cycle Design To Observe The Advantages Of Selector Phase Biology To Achieve Maximum Nutrient Removal, Sandip S. Magdum, Siva Kumar Varigala, Gauri P. Minde, Janardhan B. Bornare, V. Kalyanraman
Sandip S. Magdum
Pilot plant studies of sequential batch reactor (SBR) cycles revealed the role of selector phase biology (SPB) involved in COD removal, nitrification, denitrification and total phosphate removal. The phases namely anoxic, anaerobic and aerobic in single tank reactor design of SBR were showed effective biological nutrient removal (BNR) > 90% on average in 4 h designed cycle time with 12 h of hydraulic retention time (HRT). The phases were 2 h fill which includes 1 h simultaneous fill and aeration, 1 h settle and 1 h decant. This cycle design found effective to create selective environment for microbes to carry biological …
Tissue Engineering Scaffolds With Enhanced Oxygen Delivery Using A Cyclodextrin Inclusion Complex, Tierney Gb Deluzio
Tissue Engineering Scaffolds With Enhanced Oxygen Delivery Using A Cyclodextrin Inclusion Complex, Tierney Gb Deluzio
Tierney GB Deluzio
The development of a strategy to improve oxygen delivery to cells seeded on scaffolds is essential for the success of tissue engineering applications. The focus of this work was to explore the application of cyclodextrin inclusion complexes (CD:ICs) with perfluorocarbons as oxygen carriers. CD:ICs were prepared from alpha-cyclodextrin and perfluoroperhydrophenanthrene via co-precipitation, paste mixing, and dry mixing complexation techniques. Characterization indicated that paste mixing at a 2:1 host:guest ratio was the most effective method for complexation between the parent molecules. The CD:ICs were then successfully incorporated in 3D fibrous mats via electrospinning with poly(carbonate urethane) and polycaprolactone as biostable and …
Determination Of Surface Heating Distribution To Establish Targeted Thermal Tnvironments In Industry Hydrothermal Autoclaves, Hongmin Li, Guo-Xiang Wang, Edward Evans
Determination Of Surface Heating Distribution To Establish Targeted Thermal Tnvironments In Industry Hydrothermal Autoclaves, Hongmin Li, Guo-Xiang Wang, Edward Evans
Dr. Guo-Xiang Wang
This article presents a method for the determination of the heat flux distributions to establish the desired growth environments in autoclave reactors. The algorithm consists of three submodels including the inverse natural convection of the fluid, the inverse heat conduction in the metal wall, and the heat conduction in the insulation layer. The technique is employed to obtain the heat flux distributions that establish the same growth environment as the one predicted by the two-dimensional isothermal wall model. Based on the results, practical heater designs are proposed to improve the growth environments in such industry growth vessels.
Flow Of Solution In Hydrothermal Autoclaves With Various Aspect Ratios, Hongmin Li, Edward Evans, Guo-Xiang Wang
Flow Of Solution In Hydrothermal Autoclaves With Various Aspect Ratios, Hongmin Li, Edward Evans, Guo-Xiang Wang
Dr. Guo-Xiang Wang
A good understanding of the natural convective flow in hydrothermal autoclaves is essential for the control of the growth rate and the quality of the grown crystals. This paper presents a numerical simulation of turbulent natural convection in industry-size autoclaves with various aspect ratios. A simplified 2D axisymmetric model was developed. Numerical results were obtained for autoclaves with aspect ratios ranging from 2 to 20. Results show typical two counter-flow cells in both the bottom and upper chambers. Heat conduction through the baffle is negligible. Detailed analyses and discussions are presented to characterize the bulk flows in the upper chamber …
A Versatile Microparticle-Based Immunoaggregation Assay For Macromolecular Biomarker Detection And Quantification, Haiyan Wu, Yu Han, George G. Chase, Qiong Tang, Chen-Jung Lee, Bin Cao, Jiang Zhe, Gang Cheng
A Versatile Microparticle-Based Immunoaggregation Assay For Macromolecular Biomarker Detection And Quantification, Haiyan Wu, Yu Han, George G. Chase, Qiong Tang, Chen-Jung Lee, Bin Cao, Jiang Zhe, Gang Cheng
Dr. Jiang Zhe
The rapid, sensitive and low-cost detection of macromolecular biomarkers is critical in clinical diagnostics, environmental monitoring, research, etc. Conventional assay methods usually require bulky, expensive and designated instruments and relative long assay time. For hospitals and laboratories that lack immediate access to analytical instruments, fast and low-cost assay methods for the detection of macromolecular biomarkers are urgently needed. In this work, we developed a versatile microparticle (MP)-based immunoaggregation method for the detection and quantification of macromolecular biomarkers. Antibodies (Abs) were firstly conjugated to MP through streptavidin-biotin interaction; the addition of macromolecular biomarkers caused the aggregation of Ab-MPs, which were subsequently …
Zwitteration Of Dextran: A Facile Route To Integrate Antifouling, Switchability And Optical Transparency Into Natural Polymers, Bin Cao, Linlin Li, Haiyan Wu, Qiong Tang, Bingbing Sun, He Dong, Jiang Zhe, Gang Cheng
Zwitteration Of Dextran: A Facile Route To Integrate Antifouling, Switchability And Optical Transparency Into Natural Polymers, Bin Cao, Linlin Li, Haiyan Wu, Qiong Tang, Bingbing Sun, He Dong, Jiang Zhe, Gang Cheng
Dr. Jiang Zhe
This communication reports a facile method for zwitteration of dextran with carboxybetaine (CB), which integrates superior antifouling properties, switchability between zwitterionic and cationic forms, as well as enhanced optical transparency into one polysaccharide material. This study provides a new avenue for generating multifunctional zwitterionic CB materials in situ.
Single-And Multi-Hole Baffles-A Heat Transfer And Fluid Flow Control For Hydrothermal Growth, Edward Evans, Hongmin Li, Guo-Xiang Wang
Single-And Multi-Hole Baffles-A Heat Transfer And Fluid Flow Control For Hydrothermal Growth, Edward Evans, Hongmin Li, Guo-Xiang Wang
Dr. Guo-Xiang Wang
Hydrothermal solution growth is an important technique to grow high-quality single crystals. An autoclave, a closed cylindrical low-carbon steel vessel, is used to grow the large size crystals. A baffle located at the median height divides an autoclave into two chambers. Previous numerical studies indicate that the buoyancy-driven flow within an autoclave is very sensitive to the temperatures on the wall established by the heating. Baffles are required to establish the conditions for growth of high quality single crystals. This paper presents a numerical study of the effects of various baffles on the fluid flow and temperature fields in an …
Natural Convection Flow Structures And Heat Transfer In A Model Hydrothermal Growth Reactor, Hongmin Li, Minel Braun, Edward Evans, Guo-Xiang Wang, Govind Paudel, Jason Miller
Natural Convection Flow Structures And Heat Transfer In A Model Hydrothermal Growth Reactor, Hongmin Li, Minel Braun, Edward Evans, Guo-Xiang Wang, Govind Paudel, Jason Miller
Dr. Guo-Xiang Wang
Due to the experimental difficulties brought about by high pressure and temperature growth conditions, flow and heat transfer in industrial hydrothermal autoclaves for the growth of single quartz crystals have been studied mostly numerically. To date, most of the numerical models and associated results are not experimentally validated; only qualitative validation data from experiments done during actual crystal growth production is partly available. In this study, the authors used a model simulated reactor represented by an enclosure with two lower half sidewalls uniformly heated while the upper half sidewalls are uniformly cooled. Flow structures in the reactor are qualitatively visualized …
A Three-Dimensional Conjugate Model With Realistic Boundary Conditions For Flow And Heat Transfer In An Industry Scale Hydrothermal Autoclave, Hongmin Li, Edward Evans, Guo-Xiang Wang
A Three-Dimensional Conjugate Model With Realistic Boundary Conditions For Flow And Heat Transfer In An Industry Scale Hydrothermal Autoclave, Hongmin Li, Edward Evans, Guo-Xiang Wang
Dr. Guo-Xiang Wang
This paper presents a conjugate heat transfer model for industry size hydrothermal autoclaves. The electric heating on the wall outside surfaces is represented by constant heat fluxes. The circumferential heat flux deviation is introduced for the asymmetric factors from the surroundings. The results indicate that the temperature at the solution/wall interface is far from uniform. Circumferential temperature deviation is large enough to establish an asymmetric flow. To accurately simulate flows in industry autoclaves, one needs to use the conjugate model. The growth environment in current industry autoclaves, however, can be improved by establishing a uniform temperature on the wall/solution interface.
Three-Dimensional Flow Of Solution In An Industry-Size Hydrothermal Autoclave Subjected To Non-Uniform Heating Effects Of A Baffle On Flow And Temperature Separation, Hongmin Li, Guo-Xiang Wang, Edward Evans
Three-Dimensional Flow Of Solution In An Industry-Size Hydrothermal Autoclave Subjected To Non-Uniform Heating Effects Of A Baffle On Flow And Temperature Separation, Hongmin Li, Guo-Xiang Wang, Edward Evans
Dr. Guo-Xiang Wang
Hydrothermal growth takes place in a closed cylindrical container called an autoclave. Natural convection flow of an aqueous solution at a high temperature and a high pressure carries the nutrient. The high temperature growth condition and the natural convection flow are maintained by two independently controlled electrical heaters on the outside of the autoclave. In practice, the heating is circumferentially non-uniform. Many theoretical and numerical studies, however, assume axially symmetric heating conditions. This paper presents a numerical analysis of the three-dimensional heat transfer and fluid flow with a non-uniform heating condition. The analysis is based on an industry-size autoclave with …
One-Step Production Of Long-Chain Hydrocarbons From Waste-Biomass-Derived Chemicals Using Bi-Functional Heterogeneous Catalysts, Cun Wen, Elizabeth Barrow, Jason Hattrick-Simpers, Jochen Lauterbach
One-Step Production Of Long-Chain Hydrocarbons From Waste-Biomass-Derived Chemicals Using Bi-Functional Heterogeneous Catalysts, Cun Wen, Elizabeth Barrow, Jason Hattrick-Simpers, Jochen Lauterbach
Jason R. Hattrick-Simpers
n this study, we demonstrate the production of long-chain hydrocarbons (C8+) from 2-methylfuran (2MF) and butanal in a single step reactive process by utilizing a bi-functional catalyst with both acid and metallic sites. Our approach utilizes a solid acid for the hydroalkylation function and as a support as well as a transition metal as hydrodeoxygenation catalyst. A series of solid acids was screened, among which MCM-41 demonstrated the best combination of activity and stability. Platinum nanoparticles were then incorporated into the MCM-41. The Pt/MCM-41 catalyst showed 96% yield for C8+ hydrocarbons and the catalytic performance was stable over four reaction …
Integrating Top-Down And Bottom-Up Scaffolding Tissue Engineering Approach For Bone Regeneration, M. Ramalingam, Esmaiel Jabbari, S. Ramakrishna, A. Khademhosseini
Integrating Top-Down And Bottom-Up Scaffolding Tissue Engineering Approach For Bone Regeneration, M. Ramalingam, Esmaiel Jabbari, S. Ramakrishna, A. Khademhosseini
Esmaiel Jabbari
No abstract provided.
Effect Of Surfactants And Cosurfactants On The Phase Separation Temperature And Volatility Of Methanol/Hydrocarbon/Water Blends, Michael Cheung
Effect Of Surfactants And Cosurfactants On The Phase Separation Temperature And Volatility Of Methanol/Hydrocarbon/Water Blends, Michael Cheung
Dr. Michael Cheung
The effects of several surfactants and cosurfactants on the phase separation temperature and Reid vapor pressure of methanol/hydrocarbon/water blends were investigated.
Polymerization Of Microstructured Aqueous Systems Formed Using Methyl Methacrylate And Potassium Undecenoate, Michael Cheung
Polymerization Of Microstructured Aqueous Systems Formed Using Methyl Methacrylate And Potassium Undecenoate, Michael Cheung
Dr. Michael Cheung
No abstract provided.
Formation Of Polymeric Foams From Aqueous Foams Stabilized Using A Polymerizable Surfactant, Michael Cheung
Formation Of Polymeric Foams From Aqueous Foams Stabilized Using A Polymerizable Surfactant, Michael Cheung
Dr. Michael Cheung
Polymerization of foams formed by purging with nitrogen an aqueous precursor system made up of a polymerizable surfactant, a monomer, and a cross-linking agent yielded stable polymeric foams. The precursor system for foaming contained hydrophobic components (methyl methacrylate as monomer and ethylene glycol dimethacrylate as cross-linking agent) in water and was stabilized using the polymerizable surfactant potassium acrylamidostearate. The phase-behavior study for the precursor system was conducted followed by an investigation of the stability of the foams obtained on purging with nitrogen. Sonicating the precursor systems during the process of purging with nitrogen gas followed by polymerization resulted in aqueous …
Effects Of Heptanoic And Oleic Acid On The Phase Separation Temperatures Of Methanol/Hydrocarbon/Water Mixtures, Michael Cheung
Effects Of Heptanoic And Oleic Acid On The Phase Separation Temperatures Of Methanol/Hydrocarbon/Water Mixtures, Michael Cheung
Dr. Michael Cheung
The efficacy of heptanoic and oleic acids as phase separation temperature depressants for methanol/hydrocarbon/water blends was examined.
Characterization And Polymerization Of Middle-Phase Microemulsions In Styrene/Water Systems, Michael Cheung
Characterization And Polymerization Of Middle-Phase Microemulsions In Styrene/Water Systems, Michael Cheung
Dr. Michael Cheung
The products of photopolymerizing middle-phase microemulsions containing sodium dodecyl sulfate as a surfacant, styrene as a monomer, NaCL or NaSCN as electrolyte, and either 2-pentatol or a combination of 5-hexene-1, 2-diol and sodium styrenesulfonate as a cosurfacant were characterized by using differential scanning calorimetry, gel permeation chromatography, and scanning electron microscopy (SEM).
Microstructured Polymers Via Photopolymerization Of Non-Aqueous Organized Solutions, Michael Cheung
Microstructured Polymers Via Photopolymerization Of Non-Aqueous Organized Solutions, Michael Cheung
Dr. Michael Cheung
Structurally organized solutions containing monomers in an ethylene glycol (EG) medium were formed and polymerized to produce polymeric solids with various morphologies, and also unique thermal and mechanical properties. Previous research had demonstrated the formation of microemulsions in an aqueous medium containing methyl methacrylate (MMA) and acrylic acid (AA). However, the non-aqueous mixtures of MMA and AA with EG did not yield conventional microemulsions. Molecularly dispersed solutions were formed in the bulk of the phase diagram, while compositions closer to the demixing line exhibited critical behaviour. This paper presents the first account of the use of mixtures exhibiting critical behaviour …
Formation Of Porous Polymeric Structures By The Polymerization Of Single-Phase Microemulsions Formulated With Methyl Methacrylate And Acrylic Acid, Michael Cheung
Dr. Michael Cheung
No abstract provided.
Acid And Base Effects On The Morphology Of Composites Formed From Microemulsion Polymerization And Sol--Gel Processing, Michael Cheung
Acid And Base Effects On The Morphology Of Composites Formed From Microemulsion Polymerization And Sol--Gel Processing, Michael Cheung
Dr. Michael Cheung
Phase behaviour studies were performed for microemulsions, containing organic monomers (methyl methacrylate and acrylic acid), inorganic monomer (tetraethoxy silane (TEOS)), a cross linking agent (ethylene glycol dimethacrylate) and water, stabilized by a cationic surfactant, cetyltrimethylammonium bromide. Single phase transparent microemulsions were formed over a considerable portion of the composition domain. The effects of an acid, hydrochloric acid (HCl), and a base (NH4OH) on the gel times were studied and the catalytic action of acid and base on the overall sol–gel reaction was analysed. Organic/inorganic polymer composites were obtained from the hydrolysis and polycondensation reactions of TEOS (sol–gel process) and polymerization …
Light Scattering Study Of Polymer Network Formation In A Supercritical Diluent, Michael Cheung
Light Scattering Study Of Polymer Network Formation In A Supercritical Diluent, Michael Cheung
Dr. Michael Cheung
We have undertaken a study of the benefits of using near-critical and supercritical fluids in synthesizing microcellular foams. In this study, we use dynamic light scattering to study the formation of the polymer network directly in near-critical and supercritical freon-22. The polymer system studied is ethylene-glycoldimethacrylate+methylmethacrylate. We have previously obtained microcellular foams by direct polymerization in this system and this study elucidates the gelation process by tracking the correlation length of the inhomogeneities as a function of reaction time from the monomeric state to the gel transition.
Effects Of Precursor Composition On Pore Morphology For Thermally Polymerized Acrylic Acid/Methyl Methacrylate-Based Microemulsions, Michael Cheung
Effects Of Precursor Composition On Pore Morphology For Thermally Polymerized Acrylic Acid/Methyl Methacrylate-Based Microemulsions, Michael Cheung
Dr. Michael Cheung
Thermal polymerization has not been extensively studied as a technique for the polymerization of bicontinuous microemulsions. Other more rapid techniques have been employed such as visible- and UV-initiated polymerization. However, the industrial preparation of porous solids would be facilitated by the use of the cheaper and simpler thermal polymerization. The effects of changing composition of the precursor on the resulting matrix morphology for thermally polymerized microemulsions were studied. The factors examined were the surfactant loading of the aqueous phase, the aqueous to organic phase ratio, the monomer ratio of the organic phase, and the cross-linker content of the organic phase. …
Modeling Of Leakage In Liquid Surfactant Membrane Systems, Michael Cheung
Modeling Of Leakage In Liquid Surfactant Membrane Systems, Michael Cheung
Dr. Michael Cheung
The stability of double emulsions or liquid surfactant membranes, an important topic in liquid membrane extraction processes, was investigated. The percentage of liquid membrane leakage which reflects the stability of the liquid surfactant membranes was measured as a function of time using sodium hydroitide as a tracer. Water-in-oil emulsions were prepared with SOLTROL 220, an isoparaffinic solvent, and solvent extracted neutral oils—S100N and S500N. A stochastic model for droplet formation under the conditions of isotropic turbulence was developed. It assumes the presence of complete randomness in the process of emulsification. The mean growth rate obtained from this model is in …