Open Access. Powered by Scholars. Published by Universities.®

Engineering Science and Materials Commons™

Open Access. Powered by Scholars. Published by Universities.®

5,705 Full-Text Articles 13,337 Authors 3,092,723 Downloads 138 Institutions

All Articles in Engineering Science and Materials

Faceted Search

5,705 full-text articles. Page 191 of 206.

Environmental Value Engineering (Eve) Comparison Of A Usgbc Leadership In Energy And Environmental Design (Leed) Window System And Non-Leed Window System, Simon A. Adamtey 2012 Bowling Green State University

Environmental Value Engineering (Eve) Comparison Of A Usgbc Leadership In Energy And Environmental Design (Leed) Window System And Non-Leed Window System, Simon A. Adamtey

Master of Technology Management Plan II Graduate Projects

ABSTRACT

The need to explore environmentally friendly materials to avoid the depletion of the nonrenewable resources is very significant. The human race has been heavily dependent on nonrenewable resources since the industrial revolution. The rate of consumption of these resources is higher than the rate at which these resources replenish themselves since it has been established that most of these resources take millions of years to replenish. A critical look into the future reveals that there is a looming resource crisis since these resources are being depleted.

Fossil fuel combustion is linked to the increase in CO2 in the …


Method For Increasing The Efficiency Of Organic Photovoltaic Cells, Jinsong Huang, Yongbo Yuan 2012 Lincoln, NE

Method For Increasing The Efficiency Of Organic Photovoltaic Cells, Jinsong Huang, Yongbo Yuan

Department of Mechanical and Materials Engineering: Faculty Publications

The present invention is directed to an organic photovoltaic cell that contains one or more dipole regions generally disposed between an organic active region and the electrodes and a process for producing such an organic photovoltaic cell.


Effect Of Surface Roughness On Slip Flow In Nanoscale Polymer Films, Anoosheh Niavarani, Nikolai Priezjev 2012 Wright State University - Main Campus

Effect Of Surface Roughness On Slip Flow In Nanoscale Polymer Films, Anoosheh Niavarani, Nikolai Priezjev

Mechanical and Materials Engineering Faculty Publications

No abstract provided.


Macro And Microfluidic Flows For Skeletal Regenerative Medicine, Brandon D. Riehl, Jung Yul Lim 2012 University of Nebraska-Lincoln

Macro And Microfluidic Flows For Skeletal Regenerative Medicine, Brandon D. Riehl, Jung Yul Lim

Department of Mechanical and Materials Engineering: Faculty Publications

Fluid flow has a great potential as a cell stimulatory tool for skeletal regenerative medicine, because fluid flow-induced bone cell mechanotransduction in vivo plays a critical role in maintaining healthy bone homeostasis. Applications of fluid flow for skeletal regenerative medicine are reviewed at macro and microscale. Macroflow in two dimensions (2D), in which flow velocity varies along the normal direction to the flow, has explored molecular mechanisms of bone forming cell mechanotransduction responsible for flow-regulated differentiation, mineralized matrix deposition, and stem cell osteogenesis. Though 2D flow set-ups are useful for mechanistic studies due to easiness in in situ and post-flow …


Thin Film Growths Of Znte And Cdte On Various Substrates Using A Novel Close Space Sublimation Reactor Css4, Damian Marrufo 2012 University of Texas at El Paso

Thin Film Growths Of Znte And Cdte On Various Substrates Using A Novel Close Space Sublimation Reactor Css4, Damian Marrufo

Open Access Theses & Dissertations

Thin films of CdTe have been grown on CdS in a variety of methods for use in thin film photovoltaic systems. Limits to the efficiency of CdTe/CdS solar cells have been attributed to defects in the lattice that occur between the interface of CdS and CdTe due to a lattice mismatch. A close space sublimation (CSS) reactor known as the CSS4 was designed and fabricated in UTEP to deposit complex layers of CdTe and ZnTe on top of a CdS film that is grown via chemical bath deposition in order to obtain a CdTe photovoltaic. Unfortunately, the original design and …


A Novel Method For The Curing Of Metal Particle Loaded Conductive Inks And Pastes, David Adrian Roberson 2012 University of Texas at El Paso

A Novel Method For The Curing Of Metal Particle Loaded Conductive Inks And Pastes, David Adrian Roberson

Open Access Theses & Dissertations

The emerging technology of printed microelectronics involving the use of conductive inks in conjunction with standard printing techniques offers a fast and low waste method for creating microelectronics compared with standard manufacturing processes. A clear path to the creation of flexible electronics is present due to the ease of printing on flexible substrates. Moreover, creation of novel 3D structural electronics is possible via the integration of printing technologies and additive manufacturing (AM) techniques.

A key obstacle to the manufacturing of flexible and structural electronics comes from the temperature restrictions imposed by the substrates, which are typically polymeric. This hindrance has …


Structure Morphology And Optical Properties Of Nanocrystalline Ga2o3 Thin Films, Sampath Kumar Samala 2012 University of Texas at El Paso

Structure Morphology And Optical Properties Of Nanocrystalline Ga2o3 Thin Films, Sampath Kumar Samala

Open Access Theses & Dissertations

Gallium Oxide thin films were produced by sputter deposition by varying the substrate temperature (Ts) in a wide range (Ts=25-800 oC) and under variable deposition time. The structural characteristics and optical properties of Ga2O3 films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS) and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure and morphology of Ga2O3 films. XRD and SEM analyses indicate that the Ga2O3 films grown at lower temperatures were …


A Front Tracking Model Of The Maxus-8 Microgravity Solidification Experiment On A Ti-45.5at.% Al-8at.%Nb Alloy, Robin Mooney, Shaun McFadden, Marek Rebow, David J. Browne 2012 Technological University Dublin

A Front Tracking Model Of The Maxus-8 Microgravity Solidification Experiment On A Ti-45.5at.% Al-8at.%Nb Alloy, Robin Mooney, Shaun Mcfadden, Marek Rebow, David J. Browne

Articles

On 26th March 2010 the MAXUS-8 sounding rocket was launched from the Esrange Space Center in Sweden. As part of the Intermetallic Materials Processing in Relation to Earth and Space Solidification (IMPRESS) project, a solidification experiment was conducted on a Ti-45.5at.%Al-8at.%Nb intermetallic alloy in a module on this rocket. The experiment was designed to investigate columnar and equiaxed microstructures in the alloy. A furnace model of the MAXUS 8 experiment with a Front Tracking Model of solidification has been developed to determine the macrostructure and thermal history of the samples in the experiment. This paper gives details of results of …


Sacrificial Structure Preforms For Thin Part Machining, Scott Smith, Robert Wilhelm, Brian Dutterer, Harish Cherukuri, Gaurav Goel 2012 University of North Carolina at Charlotte

Sacrificial Structure Preforms For Thin Part Machining, Scott Smith, Robert Wilhelm, Brian Dutterer, Harish Cherukuri, Gaurav Goel

Department of Mechanical and Materials Engineering: Faculty Publications

Thin parts are often difficult to create by machining because they have insufficient static and dynamic stiffness. Accurate thin parts are difficult to achieve due to clamping forces, cutting forces, residual stresses, and chatter. Sacrificial structure preforms support the part during machining, but they are not part of the finished component. Preforms may be created in many ways, including forging, welding, gluing, casting, or additive processes. They can be used in many workpiece materials including metals, polymers, and ceramics. We describe a novel process that uses sacrificial structures to make machining insensitive to the thinness of finished parts.


The Effect Of Al, Mo, And B On The Oxidation Behavior Of Three Nb-Based Alloys, Victoria Rae Rangel 2012 University of Texas at El Paso

The Effect Of Al, Mo, And B On The Oxidation Behavior Of Three Nb-Based Alloys, Victoria Rae Rangel

Open Access Theses & Dissertations

Extensive work has been undertaken to develop niobium based structural alloys for high temperature applications. These developments have led to the increase in engine operating temperatures and better performance efficiency. New materials including alloys based on metals with higher melting points such as molybdenum and niobium with silicon are now being examined as a better alternative to nickel base superalloys. Materials with a niobium silicide based composites have the potential for higher temperature capabilities. The oxidation behavior of Nb-20Cr-10Si and Nb-20Cr-10Si-5Al has been studied in a range of temperature from 700 to 1400°C in static air. Isothermal oxidation experiments indicate …


The Effects Of Uncommon Silicides On The Oxidation Of Alloys From The Nb-Cr-Si System, Daniel Brendan Voglewede 2012 University of Texas at El Paso

The Effects Of Uncommon Silicides On The Oxidation Of Alloys From The Nb-Cr-Si System, Daniel Brendan Voglewede

Open Access Theses & Dissertations

Niobium based alloys are being tapped as potential successors to current nickel base superalloys in high temperature applications. In the aerospace industry, high temperature materials are constantly being pushed to higher temperature regimes in order to improve engine efficiency however current superalloys cannot be pushed further due to melting temperature limitations. Niobium, being a refractory metal, can withstand much higher temperatures than nickel however its oxidation properties are woefully inadequate.

The purpose of this study is to ascertain whether increased silicon additions can improve niobium oxidation properties by: forming ternary silicides with better oxidation properties and by preventing the formation …


Development Of Cost-Effective And Benign Lipid Extraction System For Microalgae, Javed Iqbal 2012 Louisiana State University and Agricultural and Mechanical College

Development Of Cost-Effective And Benign Lipid Extraction System For Microalgae, Javed Iqbal

LSU Doctoral Dissertations

A laboratory-made continuous flow lipid extraction system (CFLES) was devised to extract lipids from microalgae Nannochloropsis sp., a potential feedstock for biodiesel fuel, with a focus to assess the workable temperatures and pressures for possible scale-up applications. Using conventional solvents, the CFLES recovered 100% of the lipids recovered with conventional Soxhlet extraction (USEPA method 3540) at moderate 50 psi pressure and 100°C temperature; conditions significantly lower than those normally used in pressurized liquid extractions requiring specialized equipment. Approximately 87% of the extracted oil was successfully transesterified into biodiesel fuel. For exploring the solvent potential of biodiesel, CFLES was also tested …


A Safety Elements Model For The Building Construction Industry, Cliff Dunlap Dunlap 2012 Louisiana State University and Agricultural and Mechanical College

A Safety Elements Model For The Building Construction Industry, Cliff Dunlap Dunlap

LSU Doctoral Dissertations

The Abstract was sent to Ms. McKenzie as an attachment to an e-mail


Quantification Of Nox Reduction Via Nitrate Accumulation On A Tio2 Photocatalytic Concrete Pavement, David James Osborn 2012 Louisiana State University and Agricultural and Mechanical College

Quantification Of Nox Reduction Via Nitrate Accumulation On A Tio2 Photocatalytic Concrete Pavement, David James Osborn

LSU Master's Theses

Field trials of photocatalytic pavements were recently initiated and are presently being considered by many states (e.g., Virginia, Texas, New York, and Missouri). Results from this study originate from the country’s first air-purifying asphalt and concrete photocatalytic pavements, constructed on Dec. 20, 2010. The test area is a pavement site located on the LSU campus. The objective of the study is to validate field photocatalytic degradation of NOx in a field environment by measuring the day to day accumulation of the oxidized byproduct; nitrate salts. The mass of nitrates, produced by the real life photocatalytic pavement, were measured. The measurement …


Hurricane Damage Assessment Process For Residential Buildings, Carol C. Massarra 2012 Louisiana State University and Agricultural and Mechanical College

Hurricane Damage Assessment Process For Residential Buildings, Carol C. Massarra

LSU Master's Theses

Assessing an affected area immediately after a severe natural hazard event and saving the resulting data are vitally important in any effort to reduce future economic losses from natural hazards. These data are used as a record of buildings performance and as a major component for statistical analysis and damage modeling studies. Since these data are used as input for these studies, the data must be assessed and collected in a scientific and standardized way. Despite this requirement, neither a systematic damage assessment process nor a standardized data collection protocol is currently available in the United States to ensure that …


Wave Propagation And Dispersion In Microstructured Solids, Arkadi Berezovski, Juri Engelbrecht, Mihhail Berezovski 2012 Tallinn University of Technology

Wave Propagation And Dispersion In Microstructured Solids, Arkadi Berezovski, Juri Engelbrecht, Mihhail Berezovski

Publications

A series of numerical simulations is carried on in order to understand the accuracy of dispersive wave models for microstructured solids. The computations are performed by means of the finite-volume numerical scheme, which belongs to the class of wave-propagation algorithms. The dispersion effects are analyzed in materials with different internal structures: microstructure described by micromorphic theory, regular laminates, laminates with substructures, etc., for a large range of material parameters and wavelengths.


Heat Transfer In Microwave Heating, Zhiwei Peng 2012 Michigan Technological University

Heat Transfer In Microwave Heating, Zhiwei Peng

Dissertations, Master's Theses and Master's Reports - Open

Heat transfer is considered as one of the most critical issues for design and implement of large-scale microwave heating systems, in which improvement of the microwave absorption of materials and suppression of uneven temperature distribution are the two main objectives. The present work focuses on the analysis of heat transfer in microwave heating for achieving highly efficient microwave assisted steelmaking through the investigations on the following aspects: (1) characterization of microwave dissipation using the derived equations, (2) quantification of magnetic loss, (3) determination of microwave absorption properties of materials, (4) modeling of microwave propagation, (5) simulation of heat transfer, and …


Molecular Modeling Of Epon 862-Detda Polymer , Ananyo Bandyopadhyay 2012 Michigan Technological University

Molecular Modeling Of Epon 862-Detda Polymer , Ananyo Bandyopadhyay

Dissertations, Master's Theses and Master's Reports - Open

EPON 862 is an epoxy resin which is cured with the hardening agent DETDA to form a crosslinked epoxy polymer and is used as a component in modern aircraft structures. These crosslinked polymers are often exposed to prolonged periods of temperatures below glass transition range which cause physical aging to occur. Because physical aging can compromise the performance of epoxies and their composites and because experimental techniques cannot provide all of the necessary physical insight that is needed to fully understand physical aging, efficient computational approaches to predict the effects of physical aging on thermo-mechanical properties are needed. In this …


Evaluation Of The Thermal Performance And Cost Effectiveness Of Radiant Barrier Thermal Insulation Materials In Residential Construction, Somayeh Asadi 2012 Louisiana State University and Agricultural and Mechanical College

Evaluation Of The Thermal Performance And Cost Effectiveness Of Radiant Barrier Thermal Insulation Materials In Residential Construction, Somayeh Asadi

LSU Doctoral Dissertations

Reducing heating and cooling systems loads in buildings is a cost effective way to decrease energy consumption in residential houses. This reduction can be achieved in many ways including proper insulation of the building envelope. In recent years, considerable attention was given to the use of radiant reflective insulating barriers. Over the past years, reflective barrier insulation companies nationwide have experienced significant growth resulting in an industry average growth rate of 26.8%. This significant growth is expected to continue as a result of increased cooling demands and pressure from the energy sector and the economy. Growth is also predicted to …


High Pressure Synchrotron X-Ray Diffraction Studies Of Superprotonic Transitions In Phosphate Based Solid Acids, Juan Daniel Hermosillo 2012 University of Texas at El Paso

High Pressure Synchrotron X-Ray Diffraction Studies Of Superprotonic Transitions In Phosphate Based Solid Acids, Juan Daniel Hermosillo

Open Access Theses & Dissertations

Certain phosphate based solid acids, such as CsH2PO4 and RbH2PO4, have been shown to exhibit an abrupt, several-order-of-magnitude increase in their proton conductivity when heated above a temperature threshold. This so called superprotonic behavior allows the above-mentioned materials to function as fuel cell electrolytes at temperatures between 150C and 300C, a remarkable application that attracted significant interest especially from the automobile industry. Yet, the microscopic structures and dynamic mechanisms responsible for this behavior are not fully understood. In fact, until very recently, the very nature of the superprotonic behavior has been debate, with some groups attributing the steep proton enhancement …


Digital Commons powered by bepress