Chemical Engineering Commons^™

The Effect Of Mg²⁺ Incorporation Into The Glass Phase Of Zinc-Based Glass Polyalkenoate Cements, Basel A. Khader, Omar Rodriguez, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The suitability of glass polyalkenoate cements (GPCs) as injectable adhesives in orthopedics have been compromised by the presence of aluminum (Al), a component in the glass phase of all commercial GPCs. There has been considerable work on the development of Al-free GPCs which can be formulated based on calcium (Ca) zinc (Zn) silicate (Si) glasses. These materials, in terms of biocompatibility and mechanical properties, have potential for orthopedics. However, many of these experimental Al-free GPCs have setting times shorter than 60 s, restricting clinical applications. Here, the authors incorporate Magnesium (Mg) into the glass phase of Al-free GPCs in an …

The Effect Of Weak Confinement On The Orientation Of Nanorods Under Shear Flows, Saman Monjezi, James D. Jones, Alyssa K. Nelson, Joontaek Park

Chemical and Biochemical Engineering Faculty Research & Creative Works

We performed a numerical analysis to study the orientation distribution of a dilute suspension of thin, rigid, rod-like nanoparticles under shearing flow near a solid boundary of weak confinement. Brownian dynamics simulation of a rod was performed under various ratios of shear rate and rod diffusivity (Peclet number), as well as the center-of-mass position (wall confinement). We discuss the effects of Peclet number and wall confinement on the angle distributions, Jeffery orbit distribution and average orientation moments. The average orientation moments, obtained as a function of Peclet number and wall confinement, can be used to improve a previous shear-induced migration …

System, Devices And Methods For Molecular Separation, Sankar Nair, Christopher W. Jones, Fereshteh Rashidi, Ali A. Rownaghi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Systems, devices and methods for molecular separation including a molecular separation device comprising at least a polycrystalline metal-organic framework (MOF) and a nanocrystalline, zeolite MFI, wherein the MOF forms a polycrystalline membrane with zeolite MFI nanoparticles dispersed therein, and the MOF membrane matrix contacting and surrounding the zeolite MFI nanoparticles form a permselective nanoporous structure.

Synthesis And Electrochemical Properties Of Nickel-Rich Cathode Material Lini0.6Co0.2Mn0.2O2 With High Initial Coulombic Efficiency, Xiao-Yun Guan, Chao-Yu Hong, Jian-Ping Zhu, Wei-Li Wang, Yi-Xiao Li, Yong Yang

Journal of Electrochemistry

Nickel-rich cathode materials LiNi_0.6Co_0.2Mn_0.2O₂(NCM622)were synthesized by a co-precipitation-solid state sintering method at different temperatures. The structure, morphology and electrochemical performance of the as-prepared materials were investigated by X-ray powder diffraction (XRD) /Rietveld refinement, scanning electron microscope (SEM) and electrochemical experiments. It is found that NCM622 calcined at 800 ℃ showed the lowest degree of cation disorder (~1.97%) with a high initial Coulombic effiency of 92.2% and the capacity retention of 81.4% after 100 cycles.

Preparation And Electrocatalytic Activity Of Nitrogen-Doping Tungsten Carbide Catalyst, Pian-Pian Yang, Li-Zhen Huang, Ying-Ying Li, Mei-Qin Shi, Chun-An Ma

Journal of Electrochemistry

Tungsten carbide (WC) is a promising electrocatalyst, however, its electrocatalytic activity is far inferior to Pt and Pt-group metal. In this work, nitrogen-doping tungsten carbide (WN|WC) catalysts with a nanoplate morphology were prepared via the tungsten nitride (WN) as the precursor and sodium tungstate as the tungsten source. The SEM and TEM results indicated that carbon atoms entered into the WN lattice to form the hexagonal close packed WC phase. In this way, an atomic scale heterostructure involving the closely linked interfaces between WN and WC was created . The XRD data confirmed that the cubic crystal structure of WN …

Mechanical Properties And Flame Retardancy Of Surface Modified Magnesium Oxysulfate (5mg(Oh)2·Mgso4·3h2o) Whisker For Polypropylene Composites, Eui-Su Kim, Ye Chan Kim, Jungwoo Park, Youngjun Kim, Sung-Hoon Kim, Kwang Jin Kim, Jonghwan Suhr, Youngkwan Lee, Seong Hoon Lee, Dae-Sik Kim, Soo-Hyun Kim, Ju-Ho Yun, In-Kyung Park, Jae-Do Nam

Mechanical Engineering Faculty Research

Magnesium oxysulfate (MOS) whisker is considered as a promising inorganic material recently attracting a great attention for being used as a reinforcing filler for polymer composites due to high aspect ratio and extremely-low bulk density. In this study, the MOS was treated with 3-methacryloyloxypropyl-trimethoxy silane (MPS) via sol-gel condensation reactions, which successfully allowed melt mixing with polypropylene (PP) up to 30 wt% of MOS. The tensile strength at yield and modulus of the MOS/PP composites were substantially increased by 50.8% and 362%, respectively, when compared with the pristine PP. As a novel finding, the flame retardancy of MOS was proved …

In Situ Uv-Visible Assessment Of Iron-Based High-Temperature Water-Gas Shift Catalysts Promoted With Lanthana: An Extent Of Reduction Study, Basseem B. Hallac, Jared C. Brown, Eli Stavitski, Roger G. Harrison, Morris D. Argyle

Faculty Publications

The extent of reduction of unsupported iron-based high-temperature water-gas shift catalysts with small (< 5 wt %) lanthana contents was studied using UV-visible spectroscopy. Temperature- programmed reduction measurements showed that lanthana content higher than 0.5 wt % increased the extent of reduction to metallic Fe, while 0.5 wt % of lanthana facilitated the reduction to Fe₃O₄. In situ measurements on the iron oxide catalysts using mass and UV-visible spectroscopies permitted the quantification of the extent of reduction under temperature-programmed reduction and high-temperature water-gas shift conditions. The oxidation states were successfully calibrated against normalized absorbance spectra of visible light using the Kubelka-Munk theory. The normalized absorbance relative to the fully oxidized Fe₂O₃ increased as the extent of reduction increased. XANES suggested that the average bulk iron oxidation state during the water-gas shift reaction was Fe^{+2.57 …}

Raman Spectroscopy Predicts The Link Between Claw Keratin And Bone Collagen Structure In A Rodent Model Of Oestrogen Deficiency, M. Clare Caraher, Antonia Sophocleous, J. Renwick Beattie, Olive O'Driscoll, Niamh M. Cummins, Orlaith Brennan, Fergal J. O'Brien, Stuart H. Ralston, Steven E.J. Bell, Mark R. Towler, Aymen I. Idris

Chemical and Biochemical Engineering Faculty Research & Creative Works

Osteoporosis is a common disease characterized by reduced bone mass and an increased risk of fragility fractures. Low bone mineral density is known to significantly increase the risk of osteoporotic fractures; however, the majority of non-traumatic fractures occur in individuals with a bone mineral density too high to be classified as osteoporotic. Therefore, there is an urgent need to investigate aspects of bone health, other than bone mass, that can predict the risk of fracture. Here, we successfully predicted association between bone collagen and nail keratin in relation to bone loss due to oestrogen deficiency using Raman spectroscopy. Raman signal …

Some Insights Into The Migration Of Double Imaginary Roots Under Small Deviation Of Two Parameters, Dina Alina Irofti, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper studies the migration of double imaginary roots of the systems’ characteristic equation when two parameters are subjected to small deviations. The proposed approach covers a wide range of models. Under the least degeneracy assumptions, we found that the local stability crossing curve has a cusp at the point that corresponds to the double root, and it divides the neighborhood of this point into an S-sector and a G-sector. When the parameters move into the G-sector, one of the roots moves to the right halfplane, and the other moves to the left half-plane. When the parameters move into the …

Nanoporous Carbon-Based Co2 Reduction Catalysts: Exploring The Combined Effects Of Surface Chemistry And Porosity, Wanlu Li

Dissertations, Theses, and Capstone Projects

For the first-time sulfur-doped, nitrogen-doped and sulfur, nitrogen-codoped nanoporous carbons were systematically studied as catalysts for CO₂ electrochemical reduction reaction (CO₂ERR). The Faradaic efficiencies (FE) of CO and CH₄ formation were calculated to evaluate the performance of these carbons. The best catalysts showed the FE of CO and CH₄ formation of 29% and 0.76%, respectively. It was found that the overall performance in CO₂ERR dramatically increased upon the reduction pretreatment of the carbons in N₂-saturated electrolyte before the CO₂ reduction process. The pretreated carbon showed the maximum FE of CO …

Kinetic Modelling And Experimental Studies For The Effects Of Fe2+ Ions On Xylan Hydrolysis With Dilute-Acid Pretreatment And Subsequent Enzymatic Hydrolysis, Hui Wei, Xiaowen Chen, Joseph Shekiro, Erik Kuhn, Wei Wang, Yun Ji, Evguenii Kozliak, Michael E. Himmel, Melvin P. Tucker

Chemical Engineering Faculty Publications

High-temperature (150–170 °C) pretreatment of lignocellulosic biomass with mineral acids is well established for xylan breakdown. Fe²⁺ is known to be a cocatalyst of this process although kinetics of its action remains unknown. The present work addresses the effect of ferrous ion concentration on sugar yield and degradation product formation from corn stover for the entire two-step treatment, including the subsequent enzymatic cellulose hydrolysis. The feedstock was impregnated with 0.5% acid and 0.75 mM iron cocatalyst, which was found to be optimal in preliminary experiments. The detailed kinetic data of acid pretreatment, with and without iron, was satisfactorily modelled …

Image-Based Modeling Of Flow Through Porous Media: Development Of Multiscale Techniques For The Pore Level, Timothy Wayne Thibodeaux

LSU Doctoral Dissertations

Increasingly, imaging technology allows porous media problems to be modeled at microscopic and sub-microscopic levels with finer resolution. However, the physical domain size required to be representative of the media prohibits comprehensive micro-scale simulation. A hybrid or multiscale approach is necessary to overcome this challenge. In this work, a technique was developed for determining the characteristic scales of porous materials, and a multiscale modeling methodology was developed to better understand the interaction/dependence of phenomena occurring at different microscopic scales. The multiscale method couples microscopic simulations at the pore and sub-pore scales. Network modeling is a common pore-scale technique which employs …

Pit Evolution Around The Fusion Line Of A Nicrmov Steel Welded Joint Caused By Galvanic And Stress-Assisted Coupling Corrosion, Shuo Weng, Yuhui Huang, Fuzhen Xuan, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

The corrosion of NiCrMoV steel welded joints is performed in an aqueous solution of 3.5 wt% NaCl at 180 °C in a container at a pressure of 0.8 MPa. The specimens in the shape of cylindrical tensile rods are immersed in the aqueous solution under the action of tensile stress in a range of 0 to 0.9 of the yield stress of the base metal. The experimental results suggest that there is macro-galvanic corrosion in the welded joint with the coarse-grained heat affected zone (CGHAZ) as anode due to the highest corrosion susceptibility of the CGHAZ. The CGHAZ has the …

Correlation Of Structure, Function And Protein Dynamics In Gh7 Cellobiohydrolases From Trichoderma Atroviride, T. Reesei And T. Harzianum, Anna S. Borisova, Elena V. Eneyskaya, Suvamay Jana, Silke F. Badino, Jeppe Kari, Antonella Amore, Magnus Karlsson, Henrik Hansson, Mats Sandgren, Michael E. Himmel, Peter Westh, Christina M. Payne, Anna A. Kulminskaya, Jerry Ståhlberg

Chemical and Materials Engineering Faculty Publications

Background: The ascomycete fungus Trichoderma reesei is the predominant source of enzymes for industrial conversion of lignocellulose. Its glycoside hydrolase family 7 cellobiohydrolase (GH7 CBH) TreCel7A constitutes nearly half of the enzyme cocktail by weight and is the major workhorse in the cellulose hydrolysis process. The orthologs from Trichoderma atroviride (TatCel7A) and Trichoderma harzianum (ThaCel7A) show high sequence identity with TreCel7A, ~ 80%, and represent naturally evolved combinations of cellulose-binding tunnel-enclosing loop motifs, which have been suggested to influence intrinsic cellobiohydrolase properties, such as endo-initiation, processivity, and off-rate.

Results: The TatCel7A, ThaCel7A, …

Solid Acid Catalyst Based On Single-Layer Α-Zirconium Phosphate Nanosheets For Biodiesel Production Via Esterification, Yingjie Zhou, Iman Noshadi, Hao Ding, Jingjing Liu, Richard Parnas, Abraham Clearfield, Min Xiao, Yuezhong Meng, Luyi Sun

Henry M. Rowan College of Engineering Departmental Research

In this study, a solid acid was prepared by the sulfonation of surface modified α-zirconium phosphate (ZrP) single-layer nanosheets (SO3H@ZrP), and the prepared solid acid was investigated for the esterification of oleic acid with methanol to produce biodiesel. For comparison, liquid H2SO4 and commercial Amberlyst® 15 catalyst were also evaluated for the same reaction under the same conditions. The experimental results showed that the SO3H@ZrP solid acid catalyst has a superior catalytic efficiency for the esterification reaction, as well as excellent recyclability. The SO3H@ZrP single-layer solid acid catalyst can be uniformly dispersed in the reaction media, but remains heterogeneous and …

Comparison Of Eosin And Fluorescein Conjugates For The Photoinitiation Of Cell-Compatible Polymer Coatings, Jacob L. Lilly, Anuhya Gottipati, Calvin F. Cahall, Mohamed Agoub, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

Targeted photopolymerization is the basis for multiple diagnostic and cell encapsulation technologies. While eosin is used in conjunction with tertiary amines as a water-soluble photoinitiation system, eosin is not widely sold as a conjugate with antibodies and other targeting biomolecules. Here we evaluate the utility of fluorescein-labeled bioconjugates to photopolymerize targeted coatings on live cells. We show that although fluorescein conjugates absorb approximately 50% less light energy than eosin in matched photopolymerization experiments using a 530 nm LED lamp, appreciable polymer thicknesses can still be formed in cell compatible environments with fluorescein photosensitization. At low photoinitiator density, eosin allows more …

Specific Nanoporous Geometries On Anodized Alumina Surfaces Influence Astrocyte Adhesion And Glial Fibrillary Acidic Protein Immunoreactivity Levels, D. Ganguly, C. D.L. Johnson, M. K. Gottipati, D. Rende, D. A. Borca-Tasciuc, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electrodes implanted in the brain or spinal cord trigger the activation of resident astrocytes. In their reactive state, astrocytes surrounding the electrode form a glial scar, compromising the ability of the electrode to interface with the surrounding neural tissue. One approach to reduce the inhibiting scar tissue is to incorporate nanoarchitecture on the surface of the implanted materials to modify the astrocytic response. The incorporated nanoarchitecture changes both the surface characteristics and the material properties of the implant interface. We investigated the response of rat cortical astrocytes to nanoporous anodic aluminum oxide (AAO) surfaces. Astrocytes were seeded onto nonporous aluminum …

2017-2018 Che Newsletter, Department Of Chemical Engineering, Michigan Technological University

Department of Chemical Engineering Newsletters

Table of Contents

• Department
• Convocation
• Student News
• Faculty
• Alumni & Friends

Treatment Of Dye Wastewater Using Dehydrated Peanut Hull, Nikitha Shamirpet

ETD Archive

The release of dye waste water into environment causes harm to aquatic life when they reach drains or other water sources. They pollute the soil and causes change in cycles of plant and animal life through bio-accumulation and nutrient cycle. Dyes which form residue or precipitate causes mutations or changes in the DNA of living organisms in and around the area of release of the dye into atmosphere. In this thesis, several runs were attempted to treat the synthetically prepared dye waste water using dehydrated peanut hull. The initial dye waste water samples were all collected and checked for absorbance, …

Kinetics And Ensemble Dynamics Of Colloidal Ellipsoids Near An Ac Electrode, Jiarui Yan

ETD Archive

The manipulation of colloidal particles via applying electric fields has been studied over the past 30 years due to the unique properties associated with the fabricated colloidal crystals. Most works in this field focused on utilizing an alternating current (AC) electric field with spherical particles. However, utilizing spherical colloidal particles as building blocks for complex microstructures has been challenging. Consequently, more recent work has shifted to employing complex colloids (anisotropic in nature) as building blocks for advanced materials. In our work, the phase diagram and the kinetics of assembling colloidal polystyrene ellipsoids under an AC electric field at low frequencies …