Materials Science and Engineering Commons^™

Cellulose-Specific Type B Carbohydrate Binding Modules: Understanding Oligomeric And Non-Crystalline Substrate Recognition Mechanisms, Abhishek A. Kognole, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

Background: Effective enzymatic degradation of crystalline polysaccharides requires a synergistic cocktail of hydrolytic enzymes tailored to the wide-ranging degree of substrate crystallinity. To accomplish this type of targeted carbohydrate recognition, nature produces multi-modular enzymes, having at least one catalytic domain appended to one or more carbohydrate binding modules (CBMs). The Type B CBM categorization encompasses several families (i.e., protein folds) of CBMs that are generally thought to selectively bind oligomeric polysaccharides; however, a subset of cellulose-specific CBM families (17 and 28) appear to bind non-crystalline cellulose more tightly than oligomers and in a manner that discriminates between surface topology.

Results: …

Analysis Of Casting Defect, Tensile Strength, And Hardness Of Al-Si Casting Alloy With Percentage Variation Of Clay Binder Bangkalan, Imam Muhtarom, Sunomo Sunomo

Journal of Mechanical Engineering Science and Technology (JMEST)

Casting is one of method that used in forming the work piece by melting specific metal and pouring into moulding that has been prepared. This study aimed to determine the effect of the use of Bangkalan clay as binder in sand moulding against tensile strength, hardness, and defects in Al-Si casting alloy by using gravity casting method. The method used in this study was experimental method then using descriptive analysis. Descriptive analysis included explanation of the test result of tensile strength, hardness, and the type of surface defect of Al-Si casting. Based on the research result obtained the highest shear …

Analysis Of Hardness, Quality And Fluidity Al-Si Casting Result By Using Clamshell (Placuna Placenta) As The Mixture Of Sand Moulding, Shikh Mohd Shahrul Nizan Shikh Zahari, Saif Aziz Saputra, Putut Murdanto

Journal of Mechanical Engineering Science and Technology (JMEST)

Metal is an element that cannot be separated from human life. Almost all of human activities includes metal element in it. Metals can be formed through several ways, one of which is metal casting. Metal casting is one of technique in producing products where the metal was melted in crucible and then poured in a moulding which is similar to the original shape of the product. Moulding that are commonly used are sand moulding. Commonly, binder which used in sand casting process is bentonite. Bentonite, was kind of mineral which can be run out during its usage. This study aimed …

The Analysis Of Permeability And Mechanical Properties Of Sand Moulding Using Mixed Material Clamshell (Placuna Placenta) On Sand Casting, Kritchakhris Nawettanaprasert, Zakaria Bagus Aminanta, Putut Murdanto

Journal of Mechanical Engineering Science and Technology (JMEST)

This study objected to determine mechanical properties of sand moulding by conducting tensile test, compressive and shear test, and also permeability test. This study also had the other objective that was analyse clamshell (Placuna placenta) as mixture material for bentonite as binder in manufacturing sand moulding in order to reduce the usage of bentonite. The method that used in this study was pre-experimental method with One-Shot Case Study model. The best mechanical properties obtained on sample 3 clamshell 11%, permeability results obtained was 190 ml/min, tensile strength results obtained for the dry sand was 0.015 kg/cm2, compressive strength obtained for …

Water Processable N-Type Organic Semiconductor, Ruben S. Riquelme, Matthew Collins Weisenberger, Camila F. Gomez

Center for Applied Energy Research Faculty Patents

The present invention concerns a water-processable n-type semiconductor comprised of polyvinylpyrrolidone (PVP), carbon nanotubes (CNTs) and poly(ethyleneimine) (PEI). The semiconductors are prepared by providing PVP and CNTs in a hydrophilic slurry and dispersing therein small amounts of PEI.

The Feasibility Of High Strength Stainless Steel In Prestressing Applications For Pile Design, Cara Morton

USF Tampa Graduate Theses and Dissertations

Approximately 50% of the Nation’s infrastructure was built over 40 years ago for a 50 year service life according to the National Association of Corrosion Engineers [72]. To mitigate the cost of major repair or replacement at 50 years, AASHTO now requires all new bridge construction to have a 100 year service life. One of the main challenges in achieving this goal is avoiding corrosion, especially in warm, saltwater environments like those found in the Southeastern United States. Elements that cross the waterline (piles) are a weak link the infrastructure. Good quality concrete easily maintains a service life of 75+ …

Linking Lignin Source With Structural And Electrochemical Properties Of Lignin-Derived Carbon Materials, Wenqi Li, Yan Zhang, Lalitendu Das, Yikai Wang, Mi Li, Namal Wanninayake, Yunqiao Pu, Doo Young Kim, Yang-Tse Cheng, Arthur J. Ragauskas, Jian Shi

Biosystems and Agricultural Engineering Faculty Publications

Valorization of lignin to high-value chemicals and products along with biofuel production is generally acknowledged as a technology platform that could significantly improve the economic viability of biorefinery operations. With a growing demand for electrical energy storage materials, lignin-derived activated carbon (AC) materials have received increasing attention in recent years. However, there is an apparent gap in our understanding of the impact of the lignin precursors (i.e., lignin structure, composition and inter-unit linkages) on the structural and electrochemical properties of the derived ACs. In the present study, lignin-derived ACs were prepared under identical conditions from two different lignin …

Characterization Of Nanomaterials For Thermal Management Of Electronics, Amit Rai

Doctoral Dissertations

Recently, there has been a growing interest in flexible electronic devices as they are light, highly flexible, robust, and use less expensive substrate materials. Such devices are affected by thermal management issues that can reduce the device’s performance and reliability. Therefore, this work is focused on the study of the thermal properties of nanomaterials and the methods to address such issues. The goal is to enhance the effective thermal conductivity by adding nanomaterials to the polymer matrix or by structural modification of nanomaterials. The thermal conductivity of copper nanowire/polydimethylsiloxane and copper nanowire/polyurethane composites were measured and showed more than threefold …

Nanoparticle Catalytic Enhancement Of Carbon Dioxide Reforming Of Methane For Hydrogen Production, Nicholas Groden

Doctoral Dissertations

The U.S. produces 5559.6 million metric tons of carbon dioxide annually, of which 21% is produced by industrial processes. Steam reforming, an industrial process that accounts for 95% of all hydrogen production in industry, produces 134.5 million metric tons of carbon dioxide or around 11% of the total carbon dioxide produced by industry. This carbon dioxide is then either emitted or goes through a sequestration process that accounts for 75% of the plant's operational costs. An alternative reaction to steam reforming is dry reforming, which utilizes carbon dioxide rather than emitting it and can be used in conjunction with current …

Metal Segregation During The Solidification Of Titanium-Aluminum Alloys For 3d Printing Applications, Jwala Parajuli

Master's Theses

Titanium-Aluminum alloys are one of the widely used alloys in multiple engineering applications. They are highly preferred in Selective Laser Melting (SLM) processes due to their low density, high melting temperature, and good strength. Segregation occurs during the solidification of most alloys and produces a non-uniform distribution of atoms. In SLM, segregation may depict the type of adhesion between the two deposited interfacial layers and the strength between the interphase between an already solidified layer and a new one, and overall, the quality of the printed part. In order to avoid segregation, the understanding of the segregation behavior at atomistic …

Electrical Characterization Of Graphene And Nanodiamond Nanostructures, A Z M Nowzesh Hasan

Doctoral Dissertations

The electrical characterization on two-dimensional carbon-based graphene and nanodiamond materials was performed to improve charge transport properties for the label-free electrical biosensors. The charge transport in solution-gated graphene devices is affected by the impurities and disorders of the underlying dielectric interface and its interaction with the electrolytes. Advancement in field-effect ion sensing by introducing a dielectric isomorph, hexagonal boron nitride between graphene and silicon dioxide of a solution-gated graphene field-effect transistor was investigated. Increased transconductance due to increased charge carrier mobility is accompanied with larger ionic sensitivity. These findings define a standard to construct future graphene devices for biosensing and …

Effective Magnetic And Electric Response Of Composite Materials, Mona Hassan Alsaleh

Doctoral Dissertations

Metamaterials (MMs) are nanocomposite materials consisting of metal-dielectric resonators much smaller in size than the wavelength of the incident light. Common examples of metamaterials are based on split ring resonators (SRRs), parallel wires or strips and fishnet structures. These types of materials are designed and fabricated in order to provide unique optical responses to the incident electromagnetic radiation that are not available in naturally existing materials. The MMs can exhibit unusual properties such as strong magnetism at terahertz (THz) and optical frequencies. Additionally, negative index materials (NIMs) can provide negative index of refraction which can be used in many applications …

Mechanical Characterization Of Expanded Polystyrene Spheres Embed Sandwich Composites For Packaging Applications, Maheswaran R, Arockia Reemas S

Journal of Applied Packaging Research

This paper addresses on study of development of new packaging material comprising Expanded Polystyrene Spheres (EPS) embedded epoxy polymer based sandwich composites with aluminium skin. The density of the packing material is controlled by varying the volume of embedded spheres. In this study, the Flexural and Compression performance of Expanded Polystyrene Spheres (EPS) embedded polymer based sandwich composites with aluminium skin are investigated. The EPS volume percent in the core is 25% with epoxy matrix which makes the the density less than 1 g/cm3 for the composite. The fabricated Sandwich Composite are very light weight, the density is less than …

Early Detection Of Corrosion Via Hydrogel-Based Spectroelectrochemical Sensors, Capri Ann Price

Dissertations and Theses

The backbone of the industrialized world is comprised of refined, zerovalent metal, a material which thermodynamically favors an oxidative return to more chemically stable states. There are many methods used to slow or delay this process, such as protective coatings, sacrificial anodes, and alloys, but no method can entirely prevent corrosion. This body of work instead proposes detecting the earliest chemical markers of corrosion: that is, metal ions as they solubilize from a metal surface. Such information would allow maintenance personnel to make informed decisions about the necessity or lack thereof of preventive maintenance, and intervene before advanced damage has …

Advances In Automotive Conversion Coatings During Pretreatment Of The Body Structure: A Review, Mark Doerre, Larry Hibbitts, Gabriela Patrick, Nelson K. Akafuah

Institute of Research for Technology Development Faculty Publications

Automotive conversion coatings consist of layers of materials that are chemically applied to the body structures of vehicles before painting to improve corrosion protection and paint adhesion. These coatings are a consequence of surface-based chemical reactions and are sandwiched between paint layers and the base metal; the chemical reactions involved distinctly classify conversion coatings from other coating technologies. Although the tri-cationic conversion coating bath chemistry that was developed around the end of the 20th century remains persistent, environmental, health, and cost issues favor a new generation of greener methods and materials such as zirconium. Environmental forces driving lightweight material selection …

Effect Of Cross-Section-Change Induced Advective Flow On The Primary Dendrite Array Morphology Of Hypoeutectic Pb-Sb Alloys During Directional Solidification, K. Pandit, S. R. Upadhyay, Surendra N. Tewari

Chemical & Biomedical Engineering Faculty Publications

The morphology and distribution of primary dendrites have been examined in Pb-2.2, 5.8 and 10.8 wt. pct. Sb alloy samples directionally solidified (DSed) in ampoules shaped like an hour-glass to examine the influence of cross-section change induced advective flow on the cellular/dendritic interface. This sample design increases the advective flow of the melt towards the array tips, as the liquid-solid interface enters the neck of the ampoule, and then decreases it as the interface exits the neck. The warm solute-rich melt flowing towards the growth front suppresses the extent of side-branching, decreases the primary dendrite spacing, and increases the primary …

Structural Transformations In Porous Glasses Under Mechanical Loading. Ii. Compression, Nikolai V. Priezjev, Maxim A. Makeev

Mechanical and Materials Engineering Faculty Publications

The role of porous structure and glass density in response to compressive deformation of amorphous materials is investigated via molecular dynamics simulations. The disordered, porous structures were prepared by quenching a high-temperature binary mixture below the glass transition into the phase coexistence region. With decreasing average glass density, the pore morphology in quiescent samples varies from a random distribution of compact voids to a porous network embedded in a continuous glass phase. We find that during compressive loading at constant volume, the porous structure is linearly transformed in the elastic regime and the elastic modulus follows a power-law increase as …

Vertical Transport Study Of Iii-V Type-Ii Superlattices, Zahra Taghipour

Optical Science and Engineering ETDs

Type-II strained layer superlattice (T2SL) semiconductors hold great promise for mid- and long-wavelength infrared photodetectors. While T2SL-based materials have advanced significantly in the last three decades, an outstanding challenge to improve the T2SLs is to understand the carrier transport and its limitations, in particular along the superlattice growth layers.

In this dissertation, an overview of the current state-of-the-art InAs/GaSb T2SLs is presented. Fundamental semiconductor device equations and transport properties, including miniband conduction and the drift-diffusion parameters, are reviewed, and the fundamental limiting factors in carrier's transport are discussed. Furthermore, the standard method of electron-beam-induced current technique to measuring these parameters …

Prediction Of Metal Sample Failure From Scanning Electron Microscope Images Using Deep Learning Neural Network, Lawrence Madriaga, Ivan Novikov, Morteza Nurcheshmeh

Posters-at-the-Capitol

We present the preliminary results on using a deep learning neural network to predict a metal sample failure based on a set of images obtained with a Scanning Electron Microscope.

Various metal alloy samples were prepared according to ASTM E8/E8M-11 standards for a tensile test. Each sample was prepared for circle grid analysis and then stressed on a tensile machine. Stress and strain values were obtained for each position along the sample by measuring dimensions of each elongated circle. Increasing stress and strain values were found closer to the breakage of the sample with low values found at the holding …

Creating A Computational Tool To Simulate Vibration Control For Piezoelectric Devices, Ahmet Ozkan Ozer, Emma J. Moore

Posters-at-the-Capitol

Piezoelectric materials have the unique ability to convert electrical energy to mechanical vibrations and vice versa. This project takes a stab to develop a reliable computational tool to simulate the vibration control of a novel “partial differential equation” model for a piezoelectric device, which is designed by integrating electric conducting piezoelectric layers constraining a viscoelastic layer to provide an active and lightweight intelligent structure. Controlling unwanted vibrations on piezoelectric devices (or harvesting energy from ambient vibrations) through piezoelectric layers has been the major focus in cutting-edge engineering applications such as ultrasonic welders and inchworms. The corresponding mathematical models for piezoelectric …