Notice On Project Sym (Coordinated By Gsyf With Isel Participation) Published In Expresso, Dated 6fev2016 (In Portuguese), 2015 Instituto Superior Engenharia Lisboa
Notice On Project Sym (Coordinated By Gsyf With Isel Participation) Published In Expresso, Dated 6fev2016 (In Portuguese), João Gomes
João F Gomes
Industrial-Scale Solution Blowing Of Soy Protein Nanofibers.Pdf, Mohammad A Hassan
Mohammad Abouelreesh Hassan
Doping Plasmon-Enhanced Tio2 With Zirconia To Improve Solar Energy Harvesting In Dye-Sensitized Solar Cells, 2015 The University of Western Ontario
Doping Plasmon-Enhanced Tio2 With Zirconia To Improve Solar Energy Harvesting In Dye-Sensitized Solar Cells, Anastasia Pasche
Electronic Thesis and Dissertation Repository
Solar energy is a promising solution towards meeting the world’s ever-growing energy demand. Dye-sensitized solar cells (DSSCs) are hybrid organic-inorganic solar cells with potential for commercial application, but are plagued by inefficiency due to their poor sunlight absorption. Silver nanoparticles have been shown to enhance the absorptive properties of DSSCs, but their plasmonic resonance causes local hot spots, resulting in cell deterioration. This thesis studies the mitigation of thermal energy loss of plasmon-enhanced DSSCs by the co-incorporation of zirconia, a well-known thermostabilizer, into the cell’s photoactive material. TiO2 was also synthesized using green bio-sourced solvents in supercritical CO2 ...
Core/Shell Nanoparticles As Hybrid Platforms For The Fabrication Of A Hydrogen Peroxide Biosensor, 2015 Purdue University - Main Campus
Core/Shell Nanoparticles As Hybrid Platforms For The Fabrication Of A Hydrogen Peroxide Biosensor, Yu-Ho Won, Doreen Aboagye, Ho Seong Jang, Andrei Jitianu, L Stanciu
Core/shell nanoparticles consisting of a Fe3O4 nanoparticle core and a mesoporous silica shell (Fe3O4/m-silica) were used as a matrix for immobilization of horseradish peroxidase (HRP) enzyme and subsequent design of an amperometric hydrogen peroxide biosensor. HRP enzyme was immobilized on the core/shell nanoparticles through the electrostatic interaction between oppositely charged HRP enzyme and the silica shell at neutral pH. The enzyme-core/shell nanoparticle hybrid material was deposited on screen printed electrodes and further characterized by ultraviolet-visible (UV-vis) spectroscopy and scanning electron microscopy (SEM). This set up was used as a biosensor to detect hydrogen peroxide. The hydrogen ...
Incorporation Of High-K Hfo2 Thin Films In A-Igzo Thin Film Transistor Devices, 2015 University of Tennessee - Knoxville
Incorporation Of High-K Hfo2 Thin Films In A-Igzo Thin Film Transistor Devices, Aaron Hamilton Bales
In this study, HfO2 [hafnium oxide] thin films are investigated extensively as part of indium gallium zinc oxide (IGZO) thin film transistor (TFT) devices. They are incorporated into the TFTs, both as a gate insulator and a passivation layer. First, the HfO2 [hafnium oxide] films themselves are investigated through an annealing study and through I-V and C-V measurements. Then, HfO2 [hafnium oxide] is suggested as a replacement for commonly used SiO2 [silicon dioxide] gate insulator, as it has a dielectric constant that is 4 – 6 times higher. This higher dielectric constant allows for comparable TFT performance at a lower operation ...
Failure Simulations At Multiple Length Scales In High Temperature Structural Alloys, 2015 University of Tennessee - Knoxville
Failure Simulations At Multiple Length Scales In High Temperature Structural Alloys, Chao Pu
A number of computational methodologies have been developed to investigate the deformation and damage mechanism of various structural materials at different length scale and under extreme loading conditions, and also to provide insights in the development of high-performance materials.
In microscopic material behavior and failure modes, polycrystalline metals of interest include heterogeneous deformation field due to crystalline anisotropy, inter/intra grain or phase and grain boundary interactions. Crystal plasticity model is utilized to simulate microstructure based polycrystalline materials, and micro-deformation information, such as lattice strain evolution, can be captured based on crystal plasticity finite element modeling (CPFEM) in ABAQUS. The ...
Solution And Surface Properties Of Architecturally- And Compositionally-Complex Block Copolymers And Their Binary Mixtures, 2015 University of Tennessee - Knoxville
Solution And Surface Properties Of Architecturally- And Compositionally-Complex Block Copolymers And Their Binary Mixtures, Jesse Lawrence Davis
The spontaneous generation of complex structures from polymeric building blocks provides a simple yet effective route to create useful soft matter structures having potential application in a variety of nanotechnologies. The topology, chemical structure, block composition, and sequence of the constituent building blocks of polymers are tunable through synthetic chemistry. This tunability offers attractive opportunities to generate complex, yet well-defined structures with control over the geometry, packing symmetry, and microdomain structure. This thesis work involves the study of the self-assembly behaviors of architecturally complex amphiphilic block copolymers (ABCs). ABCs are composed of two or more chemically distinct blocks that are ...
Ion Irradiation-Induced Microstructural Change In Sic, 2015 University of Tennessee - Knoxville
Ion Irradiation-Induced Microstructural Change In Sic, Chien-Hung Chen
The high temperature radiation resistance of nuclear materials has become a key issue in developing future nuclear reactors. Because of its mechanical stability under high-energy neutron irradiation and high temperature, silicon carbide (SiC) has great potential as a structural material in advanced nuclear energy systems.
A newly developed nano-engineered (NE) 3C SiC with a nano-layered stacking fault (SFs) structure has been recently considered as a prospective choice due to enhanced point defect annihilation between layer-type structures, leading to outstanding radiation durability.
The objective of this project was to advance the understanding of gas bubble formation mechanisms under irradiation conditions in ...
Image-Based Nanocrystallography With Online Database Support, 2015 Portland State University
Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek
The crystallographic phase and morphology of many materials change with the crystal size so that new needs arise to determine the crystallography of nanocrystals. Direct space high-resolution phase-contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) when combined with tools for image-based nanocrystallography in two (2D) and three (3D) dimensions possess the capacity to meet these needs. After a concise discussion of lattice-fringe visibility spheres and maps, this paper discusses lattice-fringe fingerprinting in 2D and tilt protocol applications. On-line database developments at Portland State University (PSU) that support image-based nanocrystallography are also mentioned.
Three-Dimensional Structure Of Cdx (X= Se, Te) Nanocrystals By Total X-Ray Diffraction, 2015 Central Michigan University
Three-Dimensional Structure Of Cdx (X= Se, Te) Nanocrystals By Total X-Ray Diffraction, S. Pradhan, Z. Deng, F. Tang, Y. Ren, Peter Moeck, V. Petkov
The three-dimensional structure of oleic acid-capped CdSe and thiol-capped CdTe nanocrystals used as quantum dots has been determined by total synchrotron radiationx-ray diffraction and atomic pair distribution function analysis. Both CdSe and CdTe are found to exhibit the zinc-blende-type atomic ordering. It is only slightly distorted in CdSe implying the presence of nanosize domains and very heavily distorted in CdTe due to the presence of distinct core-shell regions. The results well demonstrate the great potential of the experimental approach and thus encourage its wider application in quantum dot research.
Crystallite Phase And Orientation Determinations Of (Mn, Ga) As/Gaas-Crystallites Using Analyzed (Precession) Electron Diffraction Patterns, 2015 Humboldt University of Berlin
Crystallite Phase And Orientation Determinations Of (Mn, Ga) As/Gaas-Crystallites Using Analyzed (Precession) Electron Diffraction Patterns, Ines Häusler, Stavros Nicolopoulos, Edgar Rauch, K. Volz, Peter Moeck
Outline of the presentation: 1. Material system: (Mn,Ga)As/GaAs-crystallites 2. Structure analysis using Nano-beam Diffraction (NBD) Precession Electron Diffraction Technique (PED) --> Structure type I + II 3. Phase and orientation mapping using ASTAR 4. Conclusion
Transmission Electron Goniometry And Its Relation To Electron Tomography For Materials Science Apoplications, 2015 Portland State University
Transmission Electron Goniometry And Its Relation To Electron Tomography For Materials Science Apoplications, Peter Moeck, P. Fraundorf
Aspects of transmission electron goniometry are discussed. Combined with high resolution phase contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) in the atomic number contrast (Z-STEM) or the phase contrast bright field mode, transmission electron goniometry offers the opportunity to develop dedicated methods for the crystallographic characterization of nanocrystals in three dimensions. The relationship between transmission electron goniometry and electron tomography for materials science applications is briefly discussed. Internet based java applets that facilitate the application of transmission electron goniometry for cubic crystals with calibrated tilt-rotation and double-tilt specimen holders/goniometers are mentioned. The so called cubic-minimalistic ...
3d Printing Of Crystallographic Models And Open Access Databases, 2015 University of Washington - Seattle Campus
3d Printing Of Crystallographic Models And Open Access Databases, Werner Kaminsky, Trevor Snyder, Peter Moeck
Provides a brief overview of opportunities for crystallography allowed by the recent developments in 3D printing technology. in combination with open access databases.
3d Printing & Open Access Databases For Crystallographic College Education, 2015 Portland State University
3d Printing & Open Access Databases For Crystallographic College Education, Peter Moeck, Jennifer Stone-Sundberg, Trevor Snyder, Werner Kaminsky, Saulius Grazulis
Presentation gives an overview of available open access databases of crystals and crystal structures, as well as discussions of how newly developed 3D printing technologies can be used to teach crystallography at the college level. Offers advice regarding conversion of crystallographic information files to 3D printing files, and shares news from the 3D printing of crystallographic models community.
Automated Nanocrystal Orientation And Phase Mapping In The Transmission Electron Microscope On The Basis Of Precession Electron Diffraction, Edgar Rauch, Joaquin Portillo, Stavros Nicolopoulos, Daniel Bultreys, Sergei Rouvimov, Peter Moeck
An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope is described. It is primarily based on the projected reciprocal lattice geometry that is extracted from electron diffraction spot patterns. Precession electron diffraction patterns are especially useful for this purpose. The required hardware allows for a scanning-precession movement of the primary electron beam on the crystalline sample and can be interfaced to any older or newer mid-voltage transmission electron microscope (TEM). Experimentally obtained crystal phase and orientation maps are shown for a variety of samples. Comprehensive commercial and open-access crystallographic databases may be used ...
Structural Identification Of Cubic Iron-Oxide Nanocrystal Mixtures: X-Ray Powder Diffraction Versus Quasi-Kinematic Transmission Electron Microscopy, Peter Moeck
Two novel (and proprietary) strategies for the structural identification of a nanocrystal from either a single high-resolution (HR) transmission electron microscopy (TEM) image or a single precession electron diffraction pattern are proposed and their advantages discussed in comparison to structural fingerprinting from powder X-ray diffraction patterns. Simulations for cubic magnetite and maghemite nanocrystals are used as examples.
Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, 2015 Portland State University
Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov
The foundations of precession electron diffraction in a transmission electron microscope are outlined. A brief illustration of the fact that laboratory-based powder X-ray diffraction fingerprinting is not feasible for nanocrystals is given. A procedure for structural fingerprinting of nanocrystals on the basis of structural data that can be extracted from precession electron diffraction spot patterns is proposed.
The Effect Of The Spatial Extent Of Double Tips On Crystallographic Image Processing For Scanning Tunneling Microscopes, 2015 Portland State University
The Effect Of The Spatial Extent Of Double Tips On Crystallographic Image Processing For Scanning Tunneling Microscopes, Jack C. Straton, Taylor T. Bilyeu, Peter Moeck
One may glean information from scanning probe microscopy images that have been obscured by signals from multiple probe tips by utilizing crystallographic image processing techniques. We build on prior work that showed how a pair of delta function tips interacting with idealized p4mm wave functions would give image obscurations at tip-separations where the quantum signal (the current reflecting interference between the two tips) and the classical signal (the remaining terms) destructively interfere in scanning tunneling microscopy. The present paper extends that result to tips that have finite spatial extent to determine the consequences of that extent. Using a bonding H₂ ...
The Development Of A Novel Polymer Based System For Gene Delivery, Anh Van Le
FIU Electronic Theses and Dissertations
Gene therapy involves the use of nucleic acids, either DNA or RNA for the treatment, cure, or prevention of human diseases. Synthetic cationic polymers are promising as a tool for gene delivery because of their high level of design flexibility for biomaterial construction and are capable of binding and condensing DNA through electrostatic interactions.
Our lab has developed a novel polymer (poly (polyethylene glycol-dodecanoate) (PEGD), a polyester of polyethylene glycol (PEG) and dodecanedioic acid (DDA). PEGD is a linear viscous polymer that self-assembles into a vesicle upon immersion in an aqueous solution. A copolymer of dodecanedioc acid and polyethylene glycol ...
Observation Of Low Energy Raman Modes In Twisted Bilayer Graphene, 2015 University of Northern Iowa
Observation Of Low Energy Raman Modes In Twisted Bilayer Graphene, Rui He, Ting Chung, Conor Delaney, Courtney Keiser, Luis Jauregui, Paul Shand, C. Chancey, Yanan Wang, Jiming Bao, Yong Chen
Paul M. Shand
Two new Raman modes below 100 cm(-1) are observed in twisted bilayer graphene grown by chemical vapor deposition. The two modes are observed in a small range of twisting angle at which the intensity of the G Raman peak is strongly enhanced, indicating that these low energy modes and the G Raman mode share the same resonance enhancement mechanism, as a function of twisting angle. The similar to 94 cm(-1) mode (measured with a 532 nm laser excitation) is assigned to the fundamental layer breathing vibration (ZO' mode) mediated by the twisted bilayer graphene lattice, which lacks long-range ...