Developments Of Photo-Assisted Fuel Cells,
2016
niversity of Chinese Academy of Sciences, 100049, Beijing, China
Developments Of Photo-Assisted Fuel Cells, Ling-Ling Zhang, Shao-Jun Dong
Journal of Electrochemistry
The exploitation and utilization of fossil fuels have led to serious energy crisis and environmental pollution. In this case, the development of renewable energy is an alternative to traditional energy consumption. Fuel cells (FCs) can convert chemical energy into electricity via the electrochemical reaction, which is green and environment-friendly. Photo-assisted FCs integrate photo-responsive components into FCs, leading to the dual routes of energy conversion including light energy to electricity and chemical energy to electricity, and thus, improving the energy utilization efficiency. The development of photo-assisted FCs is significant for practical application and promising to solve the coming energy crisis. In …
Simultaneous Metal-Insulator And Antiferromagnetic Transitions In Orthorhombic Perovskite Iridate Sr0.94Ir0.78O2.68 Single Crystals,
2016
University of Kentucky
Simultaneous Metal-Insulator And Antiferromagnetic Transitions In Orthorhombic Perovskite Iridate Sr0.94Ir0.78O2.68 Single Crystals, Hao Zheng, Jsaminka Terzic, Feng Ye, X. G. Wan, D. Wang, Jinchen Wang, Xiaoping Wang, P. Schlottmann, Shujuan Yuan, Gang Cao
Center for Advanced Materials Faculty Publications
The orthorhombic perovskite SrIrO3 is a semimetal, an intriguing exception in iridates where the strong spin-orbit interaction coupled with electron correlations tends to impose an insulating state. We report results of our investigation of bulk single-crystal Sr0.94Ir0.78O2.68 or Ir-deficient, orthorhombic perovskite SrIrO3. It retains the same crystal structure as stoichiometric SrIrO3 but exhibits a sharp, simultaneous antiferromagnetic (AFM) and metal-insulator (MI) transition occurring in the basal-plane resistivity at 185 K. Above it, the basal-plane resistivity features an extended regime of almost linear temperature dependence up to 800 K but the strong …
The Impact Of Volunteering At A Girls Outreach Activity On Community Formation,
2016
Boise State University
The Impact Of Volunteering At A Girls Outreach Activity On Community Formation, Donna C. Llewellyn, Janet Callahan, Amy J. Moll, Catherine Rose Bates
Materials Science and Engineering Faculty Publications and Presentations
This paper is focused on exploring the motivation for volunteering at an engineering outreach activity. The outreach activity itself involved a two day, overnight experience for 9th and 10th grade girls that started in 2005, and which has been held annually since that time. The outreach event takes place in Boise, Idaho, and at the time of its onset was the only outreach or camp activity in the state focused on girls or young women. Across ten years, 510 total girls have participated, with approximately 85% of them coming from the immediate metropolitan area. The program was developed with a …
The Effects Of Ionizing Radiation And Oxidizing Species On Strains Of Deinococcus Radiodurans Lacking Endogenous Oxidative Protection Methods,
2016
Air Force Institute of Technology
The Effects Of Ionizing Radiation And Oxidizing Species On Strains Of Deinococcus Radiodurans Lacking Endogenous Oxidative Protection Methods, Dylan L. Klawuhn
Theses and Dissertations
Multiple strains of Deinococcus radiodurans were transformed, creating knockout mutations in genes responsible for manganese ion transport, manganese and copper/zinc super-oxide dismutase, and bacillithiol synthesis. These mutated strains were then irradiated with ~20,000 Gys. The results showed that the mutated strains had a higher sensitivity to ionizing radiation, those responsible for bacillithiol synthesis having an increase in sensitivity 3000 times more than wild type Deinococcus radiodurans. In addition to radiation the mutated strains were also exposed to paraquat, an oxidizing herbicide. Strains missing manganese super-oxide dismutase showed increased sensitivity.
Microfacet Wavelength Scaling Of The Brdf,
2016
Air Force Institute of Technology
Microfacet Wavelength Scaling Of The Brdf, Samuel E. Freda
Theses and Dissertations
The bidirectional reflectance distribution function (BRDF) describes realistic scattering of light off materials by relating incident irradiance to outbound radiance. One popular class of BRDF models assumes a surface is comprised of tiny microfacets. The drawback of microfacet BRDFs is that they often no not contain specific material parameters and neglect wavelength effects. Wave optics BRDF expressions, however, can describe wavelength effects at the expense of being more computationally cumbersome. Previous work of following a Beckmann-Kirchhoff derivation of BRDF, then relating wave optics BRDF coordinates to microfacet coordinates led to a complicated, but versatile, BRDF. In this work, the infinite …
Observation Of Metallic Surface States In The Strongly Correlated Kitaev-Heisenberg Candidate Na2Iro3,
2016
Princeton University
Observation Of Metallic Surface States In The Strongly Correlated Kitaev-Heisenberg Candidate Na2Iro3, Nasser Alidoust, Chang Liu, Su-Yang Xu, Ilya Belopolski, Tongfei Qi, Minggang Zeng, Daniel S. Sanchez, Hao Zheng, Guang Bian, Madhab Neupane, Yu-Tzu Liu, Stephen D. Wilson, Hsin Lin, Arun Bansil, Gang Cao, M. Zahid Hasan
Center for Advanced Materials Faculty Publications
We report high-resolution angle-resolved photoemission spectroscopy measurements on the honeycomb iridate Na2IrO3. Our measurements reveal the existence of a metallic surface band feature crossing the Fermi level with nearly linear dispersion and an estimated surface carrier density of 3.2 x 1013 cm-2, which has not been theoretically predicted or experimentally observed, and provides the first evidence for metallic behavior on the boundary of this material, whereas the bulk bands exhibit a robust insulating gap. We further show the lack of theoretically predicted Dirac cones at the M¯ points of the surface Brillouin …
Anisotropic Softening Of Magnetic Excitations In Lightly Electron-Doped Sr2Iro4,
2016
Chinese Academy of Sciences, China
Anisotropic Softening Of Magnetic Excitations In Lightly Electron-Doped Sr2Iro4, X. Liu, M. P. M. Dean, Z. Y. Meng, M. H. Upton, T. Qi, T. Gog, Y. Cao, J. Q. Lin, D. Meyers, H. Ding, Gang Cao, J. P. Hill
Center for Advanced Materials Faculty Publications
The magnetic excitations in electron-doped (Sr1−xLax)2IrO4 with x = 0.03 were measured using resonant inelastic x-ray scattering at the Ir L3 edge. Although much broadened, well defined dispersive magnetic excitations were observed. Comparing with the magnetic dispersion from the undoped compound, the evolution of the magnetic excitations upon doping is highly anisotropic. Along the antinodal direction, the dispersion is almost intact. On the other hand, the magnetic excitations along the nodal direction show significant softening. These results establish the presence of strong magnetic correlations in electron-doped (Sr1−xLax …
Progress Of Carbonation In Chloride Contaminated Concretes,
2016
Shenzhen University
Progress Of Carbonation In Chloride Contaminated Concretes, Yaocheng Wang, P. A.M. Basheer, S. Nanukuttan, Y. Bai
International Conference on Durability of Concrete Structures
Concretes used in marine environment are generally under the cyclic effect of CO2 and chloride ions (Cl-). To date, the influence of carbonation on ingress of chloride ions in concretes has been widely studied; in comparison, study on the influence of Cl- on the progress of carbonation is limited. During the study, concretes were exposed to independent and combined mechanisms of carbonation and chloride ingress regimes. Profiles of apparent pH and chloride concentration were used to indicate the progress of carbonation and ingress of Cl- in concretes. From the apparent pH profile, a carbonation front …
Carbon Fiber As Anode Material For Cathodic Prevention In Cementitious Materials,
2016
Chalmers University of Technology
Carbon Fiber As Anode Material For Cathodic Prevention In Cementitious Materials, Emma Qingnan Zhang, Luping Tang, Thomas Zack
International Conference on Durability of Concrete Structures
Cathodic prevention (CPre) technique is a promising method and has been used for the past two decades to prevent steel from corrosion in concrete structures. However, wide application of this technique has been restricted due to high costs of anode materials. In order to lower the cost and further improve this technique, carbon fiber composite anode has been introduced as an alternative anode material with affordable price and other outstanding properties. This paper presents the study of using carbon fiber mesh as anode material for long-term cathodic prevention system and the effect of accelerated current on macro- and microstructure of …
Corrosion Of Steel In Concrete And Its Prevention In Aggressive Chloride-Bearing Environments,
2016
Politecnico di Milano
Corrosion Of Steel In Concrete And Its Prevention In Aggressive Chloride-Bearing Environments, Luca Bertolini, Maddalena Carsana, Matteo Gastaldi, Federica Lollini, Elena Redaelli
International Conference on Durability of Concrete Structures
This keynote paper deals with the durability of reinforced concrete (RC) structures exposed to aggressive environments characterized by high concentration of chloride ions, namely, marine environments or the use of de-icing salts. The mechanism of chloride-induced corrosion of steel in concrete is introduced, and its influence on the service life of RC structures is analyzed. Factors affecting the time to corrosion initiation are described with regard to both concrete properties and environmental exposure conditions. Design approaches available for achieving durability targets associated with the design service life are analyzed, focusing on studies carried out by the authors in recent years …
Comparison Study Of Tensile Strength , Ductility, And Fracture Mode Of H11, Arp 2000, And Mp35n Connecting Rod Bolts For Use In High Performance Racing Engines,
2016
California Polytechnic State University, San Luis Obispo
Comparison Study Of Tensile Strength , Ductility, And Fracture Mode Of H11, Arp 2000, And Mp35n Connecting Rod Bolts For Use In High Performance Racing Engines, Megan Mccabe, Samuel Randall
Materials Engineering
Oliver Racing Parts (ORP) has historically purchased connecting rod bolts made of high strength, high cost, nickel-cobalt alloy, MP35N, and a medium strength, low cost, proprietary tool steel called ARP 2000. ORP has recently acquired capabilities to manufacture their own bolts. To determine the quality of their product as it compares to their previous supplier, ORP produced three different types of ⅜” diameter bolts: one set of bolts made of MP35N, and two sets of H11 bolts, designated H11A and H11B for their respective processing. The H11, ARP 2000, and MP35N bolts were tensile tested using a custom designed test …
Improving The Mechanical Performance Of 3d Printed Parts Using Fused Filament Fabrication,
2016
California Polytechnic State University, San Luis Obispo
Improving The Mechanical Performance Of 3d Printed Parts Using Fused Filament Fabrication, Inderpreet Binning
Industrial and Manufacturing Engineering
The 3D printing industry has seen rapid growth in the last 10 years and has been called the next industrial revolution. There are several different processes used in 3D printing, but the most popular process is called Fused Filament Fabrication (FFF) or Fused Deposition Modeling (FDM). This is the process where (most commonly) plastic filament enters a nozzle, is heated to a semi-liquid state, and then deposited into a pattern to create a print. One major drawback to this process is that the prints are anisotropic. This means that the strength of the print varies with the orientation that it …
Superalloy Metallurgy A Gleeble Study Of Environmental Fracture In Inconel 601,
2016
California Polytechnic State University, San Luis Obispo
Superalloy Metallurgy A Gleeble Study Of Environmental Fracture In Inconel 601, Alan C. Demmons
Master's Theses
At temperatures above 0.5 Tm and in aggressive atmospheres predicting alloy performance is particularly challenging. Nickel alloys used in regimes where microstructure and properties are altered dynamically present unique requirements. Exposure may alter properties with unexpected early failure. The Gleeble is a valuable tool for investigation and simulation of thermo-mechanical properties of an alloy in various regimes up to the threshold of melting. In this study, four regimes of temperature and strain rate were simulated in an argon atmosphere to both investigate and document normal and abnormal failure modes. Commercial Inconel 601 was tested in selected regimes and in two …
Solution Casting And Mechanical Testing Of Arabinan-Cellulose Nanocomposites,
2016
California Polytechnic State University, San Luis Obispo
Solution Casting And Mechanical Testing Of Arabinan-Cellulose Nanocomposites, Kevin Su, Alina Lusebrink
Materials Engineering
The purpose of this work was to investigate methods to produce consistent, reliable, and testable thin films of arabinan-cellulose nanocomposites. Mechanical properties and composition of the Opuntia ficus-indica cactus spines served as motivation for this research. The high specific strength and stiffness, biodegradability, and sustainability of these spines inspired the creation of composites fabricated from the same materials found in cactus spines: arabinan and nanocrystalline cellulose (NCC). Arabinan serves as the matrix material and NCC as the reinforcement. To explore the feasibility of using a non-toxic solvent, different solution casting techniques with water as a solvent were investigated. Ultrasonication was …
Selection Of A Flexible Polymer To Protect Dry Carbon Fibers In A Cfrp Wallet Hinge,
2016
California Polytechnic State University, San Luis Obispo
Selection Of A Flexible Polymer To Protect Dry Carbon Fibers In A Cfrp Wallet Hinge, Evan Dowey, Matthew Johnson
Materials Engineering
Common Fibers, a company founded by Cal Poly alumni, produces carbon fiber wallets. The invention of their built-in fiber-matrix composite hinge reduces the need for extra complexity and added mass that is inherent with using standard metal hinges to join standard composite panels. Replacing the polyurethane tape on the wallet hinge allows for improved protection while maintaining flexibility and other performance properties is critical to the success of such a design. The most important material property in this project is the bond strength between carbon fiber and a variety of flexible resin candidates. The silicone and urethane based elastomer resins …
Effects Of Cold Work, Final Grind Diameter, And Heat Treatment On The Mechanical Properties Of Nitinol Guide Wire Tips,
2016
California Polytechnic State University, San Luis Obispo
Effects Of Cold Work, Final Grind Diameter, And Heat Treatment On The Mechanical Properties Of Nitinol Guide Wire Tips, Daniel Rodriguez
Materials Engineering
No abstract provided.
Welding Procedure Qualification Of A36 Steel Plates Using The Gtaw And Gmaw Processes,
2016
California Polytechnic State University, San Luis Obispo
Welding Procedure Qualification Of A36 Steel Plates Using The Gtaw And Gmaw Processes, Brecken Deoilers, Neri Lupian, Regan Rumph
Materials Engineering
The purpose of this project was to qualify welding procedure specifications for the Las Positas College welding program using A36 steel in accordance with American Welding Society (AWS) D1.1, B4.0, and B2.1. Qualification was to be performed using both 1G (flat) and 3G (vertical) positions for Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes. Required qualification procedures included two face and two root bend tests coupled with a visual inspection for cracks within the weld region greater than ⅛” long, along with two reduced section tensile tests to ensure the tensile strength exceeded 58 ksi if …
Effect Of Thermal Exposure On Tensile Strength And Microhardness Of Welded And Precipitation Hardened Rx82 Aluminum Alloy Extrusions In The T4 And T6 Conditions,
2016
California Polytechnic State University, San Luis Obispo
Effect Of Thermal Exposure On Tensile Strength And Microhardness Of Welded And Precipitation Hardened Rx82 Aluminum Alloy Extrusions In The T4 And T6 Conditions, Lucien Miller
Materials Engineering
This investigation is focused on the effect paint-bake cycles have on the tensile strength and microhardness of GMAW welded RX82 aluminum extrusions in T4 and T6 base conditions. To simulate the paint-bake cycle, T4 and T6 RX82 aluminum samples were GMAW welded and heat treated at 350°F, 390°F, and 425°F for durations of 30 minutes, 1.0 hour, and 2.0 hours, with five replicates for each treatment. Microhardness profiles of T4 samples treated at 350°F for 30 minutes and 1.0 hour display weld/HAZ HV values of 86.04 and 82.51 respectively, followed by maximums of 123.21 and 121.10. Average ultimate tensile strength …
Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength,
2016
California Polytechnic State University, San Luis Obispo
Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength, Nicholas Bruffey, William Shiu
Materials Engineering
The design process at Zodiac Aerospace requires the ability to accurately predict the strength of a composite honeycomb core sandwich panel to adhere to strict FAA regulations. The most common failure mode in long beam composites is in compression. Following ASTM D7249 for a four-point bend test of a long beam flexural test, a mechanical model has been developed that relates the compressive strength of glass fiber face sheets to the flexural strength of the sandwich panel. Zodiac does not currently have data on the compressive strength of the face sheets, so testing was performed to find this property. Asymmetric …
Shear Strength Of Carbon Fiber/Epoxy Hinges Using The V-Notch Rail Shear Test,
2016
California Polytechnic State University, San Luis Obispo
Shear Strength Of Carbon Fiber/Epoxy Hinges Using The V-Notch Rail Shear Test, Calvin Noetzel
Materials Engineering
The mechanical properties of carbon fiber reinforced polymer (CFRP) hinges produced by Common Fibers (Kent, Washington) are a new technology with uncharacterized mechanical properties. Currently, Common Fiber’s hinges are utilized in wallets, but in order to expand the application of the hinges to structural components, complete characterization of the mechanical properties of the hinges is necessary. To address this problem, hinges developed by Common Fibers were tested utilizing the V-Notch rail shear test, ASTM D7078, to determine the shear strength of the hinges. Two layups, [+45/-45/0]s and [0/+45/-45/0]s were produced by Common Fibers for the experiment. Hinged and …
