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Influence Of Mechanical Properties Of Paper Coating On The Crack At The Fold Problem, Seyyed Mohammad Hashemi Najafi 2019 University of Maine

Influence Of Mechanical Properties Of Paper Coating On The Crack At The Fold Problem, Seyyed Mohammad Hashemi Najafi

Electronic Theses and Dissertations

Paper coating layers are subject to various stresses and deformations in many converting processes such as calendering, printing, slitting, and folding of the paper. In some cases, products may crack during folding to generate a defect called cracking at the fold (CAF). The parameters that influence these defects are not well understood. The overall goal of this thesis is to better understand the CAF behavior as related to material properties of the coating layer.

A method was developed to produce free-standing pigmented coating layers thick enough to be tested in bending as well as tension. The mechanical properties of these ...


Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu 2019 Laboratoire des Signaux et Syst`emes (L2S) CentraleSup´elec-CNRS-Universit´e Paris Sud, 3 rue Joliot- Curie 91192 Gif-sur-Yvette cedex, France.

Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper presents a systematic method to analyse the stability of systems with single delay in which the coefficient polynomials of the characteristic equation depend on the delay. Such systems often arise in, for example, life science and engineering systems. A method to analyze such systems was presented by Beretta and Kuang in a 2002 paper, but with some very restrictive assumptions. This work extends their results to the general case with the exception of some degenerate cases. It is found that a much richer behavior is possible when the restrictive assumptions are removed. The interval of interest for the ...


The Effect Of Flinak Molten Salt Corrosion On The Hardness Of Hastelloy N, David Kok 2019 Olivet Nazarene University

The Effect Of Flinak Molten Salt Corrosion On The Hardness Of Hastelloy N, David Kok

Scholar Week 2016 - present

The Molten Salt Reactor (MSR) has been identified as a promising candidate to replace aging nuclear reactors around the world. However, a suitable combination of molten salt and container material needs to be found in order to reduce the potential for corrosion in the MSR before it can be considered commercially viable. FLiNaK molten salt and the nickel-based alloy Hastelloy N have been identified as prime candidates for this function, but the severity of FLiNaK corrosion in Hastelloy N requires additional study before this combination can be used in the operation of a MSR. In this study, Hastelloy N samples ...


Effects Of Chloride Ions In Acid-Catalyzed Biomass Dehydration Reactions In Polar Aprotic Solvents, Max A. Mellmer, Chotitath Sanpitakseree, Benginur Demir, Kaiwen Ma, William A. Elliott, Peng Bai, Robert L. Johnson, Theodore W. Walker, Brent H. Shanks, Robert M. Rioux, Matthew Neurock, James A. Dumesic 2019 University of Wisconsin–Madison

Effects Of Chloride Ions In Acid-Catalyzed Biomass Dehydration Reactions In Polar Aprotic Solvents, Max A. Mellmer, Chotitath Sanpitakseree, Benginur Demir, Kaiwen Ma, William A. Elliott, Peng Bai, Robert L. Johnson, Theodore W. Walker, Brent H. Shanks, Robert M. Rioux, Matthew Neurock, James A. Dumesic

Chemical and Biological Engineering Publications

The use of polar aprotic solvents in acid-catalyzed biomass conversion reactions can lead to improved reaction rates and selectivities. We show that further increases in catalyst performance in polar aprotic solvents can be achieved through the addition of inorganic salts, specifically chlorides. Reaction kinetics studies of the Brønsted acid-catalyzed dehydration of fructose to hydroxymethylfurfural (HMF) show that the use of catalytic concentrations of chloride salts leads to a 10-fold increase in reactivity. Furthermore, increased HMF yields can be achieved using polar aprotic solvents mixed with chlorides. Ab initio molecular dynamics simulations (AIMD) show that highly localized negative charge on Cl ...


Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto 2019 Quattrone Nanofabrication Facility

Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto

Protocols and Reports

This progress report describes fabrication of silicon nitride membranes from Si wafers using cleanroom techniques, and of nanopore preparation via a self-assembled PS-b-PMMA film. A 36.9 nm thick membrane is successfully prepared by KOH wet etching. The membrane is a layered structure of 36.8 µm thick Si and 116 nm thick silicon nitride. It is also exhibited that in the 47 nm thick PS-b-PMMA film, the nanopore structure is observed in the vicinity of a dust particle, but most of the area indicates lamellar domain structure. The thickness of PS-b-PMMA film will ...


Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two fluorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson 2019 Singh Center for Nanotechnology

Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two fluorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson

Protocols and Reports

Two reactive ion etching (RIE) processes were studied to show the relative etch selectivity between SiO2 and Si using two fluorocarbon gases, CF4 and CHF3. Results show that CHF3 gives better selectivity (16:1) over CF4 (1.2 :1). On the other hand, the etch rate of SiO2 of CF4 is approximately 52.8 nm/min, faster than CHF3 (32.4 nm/min).


Studies On Use Of Carbon Slurry, A Waste From Fertilizer Plant, In Treatment Of Waste Water, Sanjay Tewari 2019 Selected Works

Studies On Use Of Carbon Slurry, A Waste From Fertilizer Plant, In Treatment Of Waste Water, Sanjay Tewari

Dr. Sanjay Tewari

"Non biodegradable materials like heavy metals, refractory organics are not removed during the conventional treatment process. In order to meet the regulatory standards and for safe disposal, it is necessary to go for tertiary treatment. Various tertiary treatment methods include adsorption, membrane separation process, ultra filtration, reverse osmosis etc. Adsorption has been found to be efficient for the removal of most of heavy metals in waste water at lower concentrations. Activated carbon is commonly used adsorbents, however, due to its high cost and loss in regeneration, various low cost adsorbents have been investigated during recent years.

The aim of the ...


Analyzing Drug Release Kinetics From Water-Soluble Polymers, Sean M. Kelly, Arun K. Upadhyay, Akash Mitra, Balaji Narasimhan 2019 Iowa State University

Analyzing Drug Release Kinetics From Water-Soluble Polymers, Sean M. Kelly, Arun K. Upadhyay, Akash Mitra, Balaji Narasimhan

Chemical and Biological Engineering Publications

The ability to develop predictive mathematical models of therapeutic release from pharmaceutical formulations has enormous potential to enhance our understanding of such systems and improve the controlled release of the payload. The current work describes the development and testing of a one-dimensional model of drug transport from amorphous, swelling/dissolving polymers. Model parameters such as the diffusivities of water and drug, the initial loading of the drug, the polymer dissolution rate, drug-polymer interactions, and the tablet thickness were varied, demonstrating the ability to tune the release to be controlled by either drug diffusion or polymer chain disentanglement. In addition, predictions ...


Development Of Gelatin And Graphene-Based Nerve Regeneration Conduits Using 3d Printing Strategies For Electrical Transdifferentiation Of Mesenchymal Stem Cells, Metin Uz, Maxsam Donta, Meryem Mededovic, Donald S. Sakaguchi, Surya Mallapragada 2019 Iowa State University

Development Of Gelatin And Graphene-Based Nerve Regeneration Conduits Using 3d Printing Strategies For Electrical Transdifferentiation Of Mesenchymal Stem Cells, Metin Uz, Maxsam Donta, Meryem Mededovic, Donald S. Sakaguchi, Surya Mallapragada

Chemical and Biological Engineering Publications

In this study, gelatin and graphene-based nerve regeneration conduits/scaffolds possessing tailored 3D microstructures and mechanical properties were fabricated using 3D printing. The effect of 3D conduit microstructure and mechanical properties along with the applied electrical stimuli on mesenchymal stem cell (MSCs) behavior and transdifferentiation into Schwann cell (SC)-like phenotypes were investigated. The results indicated that the gelatin conduits/scaffolds had favorable 3D microstructural and mechanical properties for MSC attachment and growth. Immunocytochemistry results demonstrated that the application of electrical stimuli through the conductive graphene within the gelatin-based 3D microstructure had a profound effect on the differentiation of MSCs ...


An Experimental Study Of Fractional Wettability Effects On Gas Assisted Gravity Drainage (Gagd), ABDULLAH ABDULRAHMAN A. AL-TAMEEMI 2019 Louisiana State University and Agricultural and Mechanical College

An Experimental Study Of Fractional Wettability Effects On Gas Assisted Gravity Drainage (Gagd), Abdullah Abdulrahman A. Al-Tameemi

LSU Master's Theses

Utilizing the power of nature to solve engineering problems has been a time-honored tradition, for example, using the sunlight as a heat and light source. From this principle, the visionary idea of Gas Assisted Gravity Drainage (GAGD) came. The GAGD process utilizes the natural segregation phenomenon of fluids with different densities in order to produce oil efficiently and economically. Waterflooding processes typically do not recover more than 40% of the original oil in place (OOIP), leaving a vast amount of oil behind. A practical and well-planned enhanced oil recovery (EOR) method is needed. However, to plan a successful project, the ...


Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown 2019 Iowa State University

Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown

Mechanical Engineering Publications

In this study, we methylated hydroxyl groups (phenolic hydroxyl: Phe-OH and aliphatic hydroxyl: Aliph-OH) in soda lignin (SL) prior to solvent liquefaction to improve storage stability of the resulting oil. We investigated two methylating reagents, dimethyl sulfate (DMS) and dimethyl carbonate (DMC), for selective Phe-OH and total hydroxyl group (Phe-OH and Aliph-OH) blocking. Samples of SL, DMS-SL, and DMC-SL were depolymerized into oils under supercritical ethanol (350 °C). Both methylated lignins produced higher amounts of oils and smaller amounts of char compared to untreated SL due to suppressed charring reactions. Oil produced from SL had relatively higher functional group contents ...


Enhancing The Co-Utilization Of Biomass-Derived Mixed Sugars By Yeasts, Meirong Gao, Deon Ploessl, Zengyi Shao 2019 Iowa State University

Enhancing The Co-Utilization Of Biomass-Derived Mixed Sugars By Yeasts, Meirong Gao, Deon Ploessl, Zengyi Shao

Chemical and Biological Engineering Publications

Plant biomass is a promising carbon source for producing value-added chemicals, including transportation biofuels, polymer precursors, and various additives. Most engineered microbial hosts and a select group of wild-type species can metabolize mixed sugars including oligosaccharides, hexoses, and pentoses that are hydrolyzed from plant biomass. However, most of these microorganisms consume glucose preferentially to non-glucose sugars through mechanisms generally defined as carbon catabolite repression. The current lack of simultaneous mixed-sugar utilization limits achievable titers, yields, and productivities. Therefore, the development of microbial platforms capable of fermenting mixed sugars simultaneously from biomass hydrolysates is essential for economical industry-scale production, particularly for ...


Metabolic Engineering For Biocatalyst Robustness To Organic Inhibitors, Liam Royce, Laura R. Jarboe 2019 Iowa State University

Metabolic Engineering For Biocatalyst Robustness To Organic Inhibitors, Liam Royce, Laura R. Jarboe

Chemical and Biological Engineering Publications

Microbial production of biorenewable fuels and chemicals is often limited by inhibition of the biocatalyst, either by increasing concentrations of the product compound or by contaminant compounds in the biomass‐derived sugars. This inhibition can interfere with economically viable production. Here we discuss typical mechanisms of inhibition and methods for improving biocatalyst robustness. Inhibition often takes the form of inhibition of enzyme activity, depletion of cofactor pools, and membrane damage; methods are discussed for mitigating each of these types of inhibition. Various evolutionary schemes have been developed and implemented on a variety of inhibitory compounds, including butanol, acetic acid, furfural ...


Effect Of (Poly)Electrolytes On The Interfacial Assembly Of Peg Functionalized Gold Nanoparticles, Srikanth Nayak, Max Fieg, Wenjie Wang, Wei Bu, Surya Mallapragada, David Vaknin 2019 Iowa State University and Ames Laboratory

Effect Of (Poly)Electrolytes On The Interfacial Assembly Of Peg Functionalized Gold Nanoparticles, Srikanth Nayak, Max Fieg, Wenjie Wang, Wei Bu, Surya Mallapragada, David Vaknin

Chemical and Biological Engineering Publications

We report on the effect of interpolymer complexes (IPCs) of poly(acrylic acid) (PAA) with poly(ethylene glycol) functionalized Au nanoparticles (PEG-AuNPs) as they assemble at the vapor-liquid interface, using surface sensitive synchrotron X-ray scattering techniques. Depending on the suspension pH, PAA functions both as a weak polyelectrolyte and a hydrogen bond donor, and these two roles affect the interfacial assembly of PEG-AuNPs differently. Above its isoelectric point, we find that PAA leads to the formation of a PEG-AuNPs monolayer at the interface with hexagonal structure. In the presence of high concentration of HCl (i.e., below the isoelectric point ...


Single Enzyme Synthesis And Bio-Imitation Of Functional Nanocrystals, Abdolhamid Sadeghnejad 2019 Lehigh University

Single Enzyme Synthesis And Bio-Imitation Of Functional Nanocrystals, Abdolhamid Sadeghnejad

Theses and Dissertations

Green synthesis methods of inorganic materials have gained lots of attention due to lower pollution and toxic precursors during the synthesis. One of the modern green methods of synthesis is biosynthesis in which a DNA, small peptide molecule, or amino acids plays the main role of synthesis. Biomineralization, the biosynthesis process happens in the nature by elements, has been considered as a green, low cost, and scalable method of synthesis. In comparison with conventional synthesis methods, biomineralization happens under ambient conditions in aqueous phase that can be applied for synthesis of inorganic nanostructure metal sulfide semiconductors gained interest due to ...


Degradation And Hydrate Phase Equilibria Measurement Methods Of Monoethylene Glycol, Khalid Alef, Stefan Iglauer, Ahmed Barifcani 2019 Edith Cowan University

Degradation And Hydrate Phase Equilibria Measurement Methods Of Monoethylene Glycol, Khalid Alef, Stefan Iglauer, Ahmed Barifcani

ECU Publications Post 2013

Monoethylene glycol (MEG), a common chemical used for the inhibition of gas hydrate formation may undergo degradation in the regeneration/reclamation process. Limited research exists on the effect of degradation of MEG on hydrate formation, production facilities and equipment especially in the presence of other chemical additives. The proposed method allows for streamlining the process of preparing, degrading and analysis of MEG solutions for hydrate testing and degradation products.

Procedure to prepare accurate MEG solutions avoiding oxidative degradation of MEG (i.e., controlling oxygen ingress).

Two methods are suggested to mimic field-like degradation of MEG solutions (i.e., degradation by ...


Modeling Cell Line-Specific Recruitment Of Signaling Proteins To The Insulin-Like Growth Factor 1 Receptor, Keesha E. Erickson, Dipak Barua, For full list of authors, see publisher's website. 2019 Missouri University of Science and Technology

Modeling Cell Line-Specific Recruitment Of Signaling Proteins To The Insulin-Like Growth Factor 1 Receptor, Keesha E. Erickson, Dipak Barua, For Full List Of Authors, See Publisher's Website.

Chemical and Biochemical Engineering Faculty Research & Creative Works

Receptor tyrosine kinases (RTKs) typically contain multiple autophosphorylation sites in their cytoplasmic domains. Once activated, these autophosphorylation sites can recruit downstream signaling proteins containing Src homology 2 (SH2) and phosphotyrosine-binding (PTB) domains, which recognize phosphotyrosine-containing short linear motifs (SLiMs). These domains and SLiMs have polyspecific or promiscuous binding activities. Thus, multiple signaling proteins may compete for binding to a common SLiM and vice versa. To investigate the effects of competition on RTK signaling, we used a rule-based modeling approach to develop and analyze models for ligand-induced recruitment of SH2/PTB domain-containing proteins to autophosphorylation sites in the insulin-like growth factor ...


Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski 2018 Wojciech Budzianowski Consulting Services

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Coating Component Migration In Paper Coatings, Emilia Purington 2018 University of Maine

Coating Component Migration In Paper Coatings, Emilia Purington

Electronic Theses and Dissertations

In many applications such as in paints and coatings, pigments are mixed with polymeric binders to generate the final product. In the coating of paper, properties like strength, durability, and print quality are affected not only by the binder type, but the final location of the binder relative to the pigments and the fibers. During the application and drying of a paper coating, binder is known to migrate. A number of methods are available to measure the migration of latex or starch. However, all of these methods have some limitations, especially when starch, latex and kaolin are components of the ...


The Creation, Validation, And Implementation Of The Engineering Process Safety Research Instrument, Brittany Lynn Butler 2018 Rowan University

The Creation, Validation, And Implementation Of The Engineering Process Safety Research Instrument, Brittany Lynn Butler

Theses and Dissertations

The purpose of this study was to develop and validate an instrument that can measure how senior chemical engineering students make process safety decisions. The Engineering Process Safety Research Instrument (EPSRI) contains dilemmas that represent process safety scenarios, followed by three decision options, and 12-15 considerations that fall into pre-conventional, conventional, or post-conventional forms of reasoning. Three studies were completed as a part of this research. The content validation study ensured the dilemmas represented process safety scenarios, the considerations matched their perceived theoretical definitions, and that no content areas were omitted. This study resulted in validation of the content, following ...


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