Materials Science and Engineering Commons^™

Magnetic Field Induced Strain In Polycrystalline Magnetic Shape Memory Foam, Cassie Lynne Witherspoon

Boise State University Theses and Dissertations

Magnetic shape memory alloys (MSMA) are fascinating materials that show a recoverable shape change in a rotating magnetic field. Single crystalline MSMA’s display magnetic-field-induced strains (MFIS) up to 10%. However, single crystals have inherent drawbacks such as cost and chemical segregation during production. Polycrystalline materials are easier to produce and display chemical homogeneity but display a much smaller MFIS than single crystals. It has been shown recently that adding porosity to polycrystalline Ni-Mn-Ga (i.e. metal foam) can increase MFIS.

Variables that affect the performance of polycrystalline Ni-Mn-Ga foam include phase transformation temperature, pore architecture, spatial distribution of pores, porosity, training, …

Probabilistic Fatigue Life Prediction Model For Alloys With Defects: Applied To A206, R. Kapoor, Vittal S. Rao, R. S. Mishra, J. A. Baumann, G. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

A model for the prediction of fatigue life based on the statistical distribution of pores, intermetallic particles and grains is presented here. This has been applied to a cast Al alloy A206 before and after friction stir processing (FSP). the model computes the probability of initiating a small crack based on the probability of finding combinations of defects and grains on the surface. Crack initiation and the propagation life of small cracks due to these defect and grain combinations are computed and summed to obtain the total fatigue life. the defect and grain combinations are ranked according to total fatigue …

Integrating Phase Change Materials In Building Materials: Experimentation, Characterization And Numerical Simulation, Esvar Subramanian

All Theses

Phase Change Materials (PCM) have many commercial applications, including in buildings to reduce cooling and heating loads. However, the lack of research has prevented their use as a common building material. This research is part of a larger project that aims at developing a set of practical design guidelines for integrating PCM in buildings. A review of and classification of common PCM available on the market is provided. The thesis then focuses on the experimental characterization of the thermo-physical properties of PCM-integrated building materials and the development of a numerical model for the thermal analysis of buildings with PCM. Different …

Growth Of Oriented Nickel-Manganese-Gallium Single Crystals Via The Bridgman Method, Douglas Leroy Kellis

Boise State University Theses and Dissertations

A Bridgman furnace was designed and built to grow oriented single crystals of nickel-manganese-gallium. The starting alloys were produced from high purity elements. The compositions of the alloys and single crystals were determined with energy dispersive x-ray spectroscopy. Oxygen concentration of the starting elements, the alloys, and single crystal were determined with the LECO combustion method. Starting seeds were produced from single crystal ingots produced at ETH Zurich, Switzerland, and from a single crystal grown from these seeds. Crystallographic orientation of the starting seeds and the single crystals were determined with x-ray diffraction. Mechanical testing was performed on a single …

Migration Models - Comparison Of Pvc, Pet And Pla Diffusivity, Combined With A Production Cost Model For Westridge Laboratories, Shelley Cooke, Sarina Surrette

Materials Engineering

This project has two parts: [1] a migration and diffusivity model for candidate plastics used in containers, and [2] a product cost model for Westridge Laboratories (Santa Ana, CA).

Diffusion modeling is a useful tool to predict migration of polymer constituents into exposed liquids.  Polyvinyl chloride (PVC), polyethylene terephthalate (PET) and polylactic acid (PLA) were studied to estimate production costs, and component migration into water-based liquids from plastic containers.  Bis (2-ethylhexyl) phthalate (DEHP), antimony trioxide, and stannous octoate, are components of concern in the three candidate polymers, respectively.  Normal detection limits for these constituents are about 1 - 10 ppb, …

An Evaluation Of The Performance Characteristics Of Olivine Temper In Pueblo Ii Virgin River Puebloan Ceramics, Sharlyn Anderson

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to examine the technological properties of the three dominant temper types - olivine, sand, and sherd - used by the Virgin Branch Puebloan during the Pueblo II era (AD 1000-1500) to explain the high proportion of Moapa Gray Ware traded to the Moapa Valley at that time. The research is guided by the hypothesis that olivine tempered pottery - or Moapa Gray Ware - possessed superior technological qualities than locally made wares, and that these qualities fueled the demand of Moapa Gray Ware ceramics.

This thesis evaluates one possibility for explaining the transportation of …

Peripheral Soldering Of Flip Chip Joints On Passive Rfid Tags, Md Syful Islam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Flip chip is the main component of a RFID tag. It is used in billions each year in electronic packaging industries because of its small size, high performance and reliability as well as low cost. They are used in microprocessors, cell phones, watches and automobiles. RFID tags are applied to or incorporated into a product, animal, or person for identification and tracking using radio waves. Some tags can be read from several meters away or even beyond the line of sight of the reader. Passive RFID tags are the most common type in use that employ external power source to …

Thin-Film Fabrication For High Pressure Thermoelectric And Electrical Resistivity Studies, Jorge L. Reynaga, Rama Venkat, Ravhi S. Kumar

Festival of Communities: UG Symposium (Posters)

Thermoelectric materials are of interest for application such as thermoelectric cooler in microprocessors and power generators in cars. High pressure plays an important role in understanding the changes in the figure of merit of thermoelectric thin films. To study the thermoelectric thin films a direct approach is to fabricate the thin film on the surface of a diamond anvil, so that the pressure dependence of structure and transport properties can be investigated easily. If we could successfully fabricate the electrical probes by depositing thin films, then it reduces the use of electrical wires as probes inside the diamond cell, as …

Graphene: Material That Will Change The Future, Jigar Desai, Darryl Reese

Festival of Communities: UG Symposium (Posters)

Graphene is the most recent material discovered by scientists and is a star on the horizon of materials science and condensed matter physics. The one atom thick, two dimensional materials is an amazing conductor of electricity. Although graphene was not discovered completely until 2004, it has already revealed potential applications and scientists have begun researching ways of developing graphene products for the market. Only two products have been successfully produced so far, but scientists have encountered amazing results. This material has many potential applications in the real world and is about to change the future in a positive way.

Minimization Of Surface Impurities In Anodized Aluminum, Logan Ward, Steven Livers, Amber Huddleston

College of Engineering Poster Presentations

Anodized aluminum is commonly used to create wear-resistant parts for process tools used in the semiconductor industry. Sinc microchips require high purity manufacturing environments[1], surface impurities on tooling needs to be minimized.

It has been determined that anodized aluminum parts are one source of contamination. This project investigates the source of trace elements in anodized aluminum 6061 parts and ways to reduce them.

Long Term Outdoor Testing Of Low Concentration Solar Modules, Lewis Fraas, James Avery, Leonid Minkin, H. X. Huang, Tim Hebrink, Robert F. Boehm

Mechanical Engineering Faculty Research

A 1‐axis carousel tracker equipped with four 3‐sun low‐concentration mirror modules has now been under test outdoors at the University of Nevada in Las Vegas (UNLV) for three years. There are three unique features associated with this unit. First, simple linear mirrors are used to reduce the amount of expensive single crystal silicon in order to potentially lower the module cost while potentially maintaining cell efficiencies over 20% and high module efficiency. Simple linear mirrors also allow the use of a single axis tracker. Second, the azimuth carousel tracker is also unique allowing trackers to be used on commercial building …

Development Of Approximating Functions To Model And Predict The Properties Of Fresh And Hardened Fly Ash-Based Geopolymer Concrete, Eleazar Ivan Diaz Loya

Doctoral Dissertations

The manuscript presented herein is based on the investigation of the mechanical properties of fly ash-based geopolymer concrete and their link to fly ash (FA) characteristics. A database of 32 FA samples was created. Each FA sample was analyzed in terms of chemical composition, crystallographic properties and particle size distribution. The mechanical performance of geopolymer concrete (GPC) made from each FA sample was evaluated in terms of density, setting time, compressive and flexural strength, static elastic modulus and Poisson's ratio. It is worth mentioning that the author has already published preliminary results of this study (Diaz and Allouche, 2010; Diaz …

The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati

Makara Journal of Technology

Eucheuma cottonii seaweed is a species of seaweed cultured in Indonesian waters, because its cultivation is relatively easy and inexpensive. It has a wide variety of colors from green to yellow green, gray, red and brown, indicating photosynthetic pigments, such as chlorophyll and carotenoids. An important factor in the effectiveness of pigment extraction is the choice of solvent. The correct type of solvent in the extraction method of specific natural materials is important so that a pigment with optimum quality that is also benefical to the society can be produced. The target of this research is to obtain a high …

Effect Of Slide Gate And Embr On The Transport Of Inclusions And Bubbles In Slab Continuous Casting Strands, Yufeng Wang, Anping Dong, Lifeng Zhang

Materials Science and Engineering Faculty Research & Creative Works

This study is to investigate the effect of electromagnetic brake (EMBr) on fluid flow and particle motion in steel slab continuous casting strands. the effect of slide gate moving on fluid flow pattern was discussed. a strong swirl and asymmetrical flow at the outports and, subsequently, inside the slab mold, was induced by slide gate. the application of EMBr would be a remedy to the swirl flow in the casting mold. Flow pattern has great influence on the trajectories of injected bubbles and nonmetallic inclusions. More bubbles tend to release from the top surface near the wide face opposite to …

Section Abstracts: Astronomy, Mathematics And Physics With Materials Science

Virginia Journal of Science

Abstracts for the Astronomy, Mathematics, and Physics with Materials Science Section for the 89th Annual Meeting of the Virginia Academy of Science, May 25-27, 2011, University of Richmond, Richmond VA.

Research On Coupled Human And Natural Systems (Chans): Approach, Challenges, And Strategies, Marina Alberti, Heidi Asbjornsen, Lawrence A. Baker, Nicholas Brozović, Laurie E. Drinkwater, Scott A. Drzyzga, Claire A. Jantz, José Fragoso, Daniel S. Holland, Timothy A. Kohler, Jianguo Liu, William J. Mcconnell, Herbert D. G. Maschner, James D. A. Millington, Michael Monticino, Guillermo Podestá, Robert Gilmore Pontius Jr., Charles L. Redman, Nicholas J. Reo, David J. Sailor, Gerald Urquhart

Mechanical and Materials Engineering Faculty Publications and Presentations

Understanding the complexity of human–nature interactions is central to the quest for both human well-being and global sustainability. To build an understanding of these interactions, scientists, planners, resource managers, policy makers, and communities increasingly are collaborating across wide-ranging disciplines and knowledge domains. Scientists and others are generating new integrated knowledge on top of their requisite specialized knowledge to understand complex systems in order to solve pressing environmental and social problems (e.g., Carpenter et al. 2009). One approach to this sort of integration, bringing together detailed knowledge of various disciplines (e.g., social, economic, biological, and geophysical), has become known as the …

Experimental Investigation Of Natural Fiber Reinforced Composite, Irene Samy Fahim

Theses and Dissertations

There is a growing use of polymers in different applications worldwide. This phenomenon resulted in an enormous increase in the amount of plastic waste. These wastes have significant impacts on the environment including pollution and depletion of resources. Recycling plastic waste and reusing it helps in alleviating environmental degradation. The amount of recycled plastics all over the world not utilized is huge. U.S.A recycled 5.7% of the total plastics generated and Western Europe recycled 39% of total amount of plastics consumed [1]. This research studies the potential usage of virgin and recycled polymer reinforced with natural fiber such as rice …

Circuit Design For Sensor Detection Signal Conditioner Nitrate Content, Robeth Viktoria Manurung, Aminuddin Debataraja, Hiskia Hiskia

Makara Journal of Technology

Circuit Design for Sensor Detection Signal Conditioner Nitrate Content. Nitrate is one of macro nutrients very important for agriculture. The availability of nitrate in soil is limited because it is very easy to leaching by rain, therefore nitrate could be contaminated ground water by over-process of fertilizer. This process could also produce inefficiency in agriculture if it happened continuesly without pre-analysis of farm field. The answer those problems, it is need to develop the ion sensor system to measure concentrations of nitrat in soil. The system is consist of nitrate ion sensor device, signal conditioning and data acquisition circuit. The …

Production Of Lovastatin And Sulochrin By Aspergillus Terreus Using Solid State Fermentation, Rizna Triana Dewi, Nina Artanti, Hani Mulyani, Puspa Dewi Narrij Lotulung, Minarti Minarti

Makara Journal of Technology

Lovastatin is an anti-cholesterol agent that was produced by Aspergillus terreus using solid state fermentation (SSF). During this fermentation process, sulochrin is also produced as an unwanted co-metabolite. However, our previous result showed that sulochrin had potential as antidiabetes because it is an inhibitor agent of α-glucosidase. In this paper, we reported our observation on lovastatin and sulochrin production pattern in relation with inhibitor α-glucosidase activity during eleven days fermentation of A. terreus koji (SSF) ethyl acetate extract. Koji obtained from solid state fermentation with rice as the substrate and incubated at room temperature, sample is taken daily for eleven …

The Zonation Of Abration Speed Characteristics And Its Handling Technique Of Jalinbar Of North Bengkulu As Vital Band Transportation, Suwarsono Suwarsono, Supiyati Supiyati, Suwardi Suwardi

Makara Journal of Technology

The Zonation of Abration Speed Characteristics and its Handling Technique of Jalinbar of North Bengkulu as Vital Band Transportation. Jalinbar Bengkulu is a vital infrastructure for traffic service, goods, agriculture products, mining, plantation and oils distribution. Abration due to scour of seawater often make these roads jammed and discrupts the peoples economy movement. The aims of this research was to investigate the abration speed of all segment of Jalinbar. The research method was a combination of two methods: A determination of swash energy of sea water using photometer and determination of rocks binding energy using douche method. The result shows …