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- Astrobiology; Carbonaceous; Chondrites; Meteorites; Micro raman; Microraman; Raman; Spectroscopy (1)
- Bscco (1)
- Bscco; Mesa; Superconductivity; Terahertz (1)
- Carbon disulfide; Nonlinear refractive index; Vapors (1)
- Carbon nanotubes; Electrophoresis; Field effect transistors; Nanoelectronics; Semiconductor (1)
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- Classical tests; General relativity; Modified gravity; Perihelion; Precession; String theory (1)
- H2 no reduction; No reduction; No reduction by hydrogen; Palladium catalyst; Pd catalyst; Pd supported on zirconia; Pd zro2 (1)
- High temperature (1)
- Hiv; hiv 1 capsid protein; molecular dynamics; monte carlo (1)
- Pnipam; Polymer; Raman; Spectroscopy (1)
- Radiation (1)
- Superconductor (1)
- Terahertz (1)
Articles 1 - 9 of 9
Full-Text Articles in Physics
Terahertz Radiation From High-Temperature Superconducting Bscco Mesas Of Various Geometries, Daniel P. Cerkoney
Terahertz Radiation From High-Temperature Superconducting Bscco Mesas Of Various Geometries, Daniel P. Cerkoney
HIM 1990-2015
The purpose of this thesis is to examine the radiation from high-temperature superconducting mesas of Bi2Sr2CaCu2O8+ (BSCCO). This is motivated by the need for coherent sources of continuous wave terahertz (THz) emission capable of radiating practically in the THz frequency band. As BSCCO has been shown to be tunable from 0.5–2.4 THz (i.e., through the entire socalled terahertz gap centered about 1 THz), and has a higher peak operating temperature near 1 THz than most alternative sources, it is a good candidate for imaging and spectroscopy device applications [1]. When a static DC voltage is applied to a BSCCO mesa, …
Angular Dependence Of The Emission From The Intrinsic Josephson Junction In Pie-Shaped Wedge Triangular Bscco Mesas, Manuel Morales
Angular Dependence Of The Emission From The Intrinsic Josephson Junction In Pie-Shaped Wedge Triangular Bscco Mesas, Manuel Morales
HIM 1990-2015
The purpose of this thesis is to determine the radiation patterns from an acute isosceles triangular superconducting mesa modeled by a pie-shaped geometry. The terahertz band lies between the microwave and infrared regions of the electromagnetic spectrum. The terahertz radiation from atomic-scale layered superconducting mesas is caused by the tunneling of electron pairs in the ac-Josephson effect. To determine the terahertz power radiated per unit solid angle of an acute isosceles triangular superconducting mesa, a model was employed in which the shape of the mesa is approximated as a pie-shaped wedge. This model is shown to have an accuracy of …
Periodic Nonlinear Refractive Index Of Carbon Disulfide Vapors, Evelyn Strunk
Periodic Nonlinear Refractive Index Of Carbon Disulfide Vapors, Evelyn Strunk
HIM 1990-2015
The purpose of this thesis is to explore the nonlinear refractive index of carbon disulfide vapors as opposed to its liquid form. With CS[sub2] vapors, the vapors are less dense so they will rotate longer than liquid CS[sub2] because there are less intermolecular interactions. The electric field of the beam causes the molecules to align with the electric field and applies a torque to the molecules. After this excitation, the molecules continue rotating. The rotations change the index of refraction of the material. Continuous rotation of the molecules causes the index of refraction to be periodic which means the molecules …
Coarse Grained Monte Carlo Simulation Of The Self-Assembly Of The Hiv-1 Capsid Protein, Jeffrey Weber
Coarse Grained Monte Carlo Simulation Of The Self-Assembly Of The Hiv-1 Capsid Protein, Jeffrey Weber
HIM 1990-2015
In this study, a Monte Carlo simulation was designed to observe the self-assembly of the HIV-1 capsid protein. The simulation allowed a coarse grained model of the capsid protein with defined interaction sites to move freely in three dimensions using the Metropolis criterion. Observations were made as to which parameters affected the assembly the process. The ways in which the assembly were affected were also noted. It was found that proper dimerization of the capsid protein was necessary in order for the lattice to form properly. It was also found that a strong trimeric interface could be responsible for double-layered …
Pressure And Temperature Response Of A Stimuli-Responsive Polymer Probed With Raman Microscopy, Coleman Cariker
Pressure And Temperature Response Of A Stimuli-Responsive Polymer Probed With Raman Microscopy, Coleman Cariker
HIM 1990-2015
Poly(N-isopropylacrylamide) (PNIPAM) is a thermo-responsive hydrogel; that is, it is a macromolecule which exists in a hydrated state beneath its lower critical solution temperature (LCST). Polymers such as PNIPAM undergo a phase transition in response to changes in temperature, pressure, pH, salt concentration, and the addition of co-solvents. Previously, visible-light microscopic measurements of the pressure-induced phase transition have been hindered by the lack of a pressurization apparatus with the short working distance and optical transmission properties necessary for high resolution microscopy. We employ a high pressure setup which uses a fused silica micro-capillary to contain the sample. Our experiment reveals …
Micro-Raman Spectroscopy Of Carbonaceous Chondrite Meteorites, Asmail Habach
Micro-Raman Spectroscopy Of Carbonaceous Chondrite Meteorites, Asmail Habach
HIM 1990-2015
Analyzing the constituents of meteorites has played an important role in forming the contemporary theories of solar system evolution, planets formation, and stellar evolution. Meteorites are often a complex mixture of common rock forming silicates, such as olivines and pyroxenes, with a range of exotic species including hydrated silicates, and in some cases organic compounds. We used Micro-Raman spectroscopy to analyze the compositions of three carbonaceous chondrites: NWA852, Murchison and Allende. Raman spectra were measured using laser sources with different excitation wavelengths: HeNe 633 nm and Nd:YAG 532 nm. We were able to detect 9 minerals in NWA852, 3 minerals …
Modification To Einstein's Field Equations Imposed By String Theory And Consequences For The Classical Tests Of General Relativity, Christopher Frye
Modification To Einstein's Field Equations Imposed By String Theory And Consequences For The Classical Tests Of General Relativity, Christopher Frye
HIM 1990-2015
String theory imposes slight modifications to Einstein's equations of general relativity (GR). In (4), the authors claim that the gravitational field equations in empty space, which in GR are just R [subscript greek letters mu nu ] = 0, should hold one extra term which is first order in the string constant [alpha'] and proportional to the Riemann curvature tensor squared. They do admit, however, that this simple modification is just schematic. In (1) the authors use modified equations which are coupled to the dilation field. We show that equations given in (4) do not admit an isotropic solution; justification …
High Yield Assembly And Electron Transport Investigation Of Semiconducting-Rich Local-Gated Carbon Nanotube Field Effect Transistors, Kristy Kormondy
High Yield Assembly And Electron Transport Investigation Of Semiconducting-Rich Local-Gated Carbon Nanotube Field Effect Transistors, Kristy Kormondy
HIM 1990-2015
Single-walled carbon nanotubes (SWNTs) are ideal for use in nanoelectronic devices because of their high current density, mobility and subthreshold swing. However, assembly methods must be developed to reproducibly align all-semiconducting SWNTs at specific locations with individually addressable gates for future integrated circuits. We show high yield assembly of local-gated semiconducting SWNTs assembled via AC-dielectrophoresis (DEP). Using individual local gates and scaling the gate oxide shows faster switching behavior and lower power consumption. The devices were assembled by DEP between prefabricated Pd source and drain electrodes with a thin Al/Al2O3 gate in the middle, and the electrical characteristics were measured …
Size-Effect Of Pd Nanoparticles Supported On Zro2 In The Catalytic Reduction Of No By H2, Young Woo Joh
Size-Effect Of Pd Nanoparticles Supported On Zro2 In The Catalytic Reduction Of No By H2, Young Woo Joh
HIM 1990-2015
Size-selected Pd nanoparticles were synthesized by the reverse-micelle encapsulation method and deposited on a ZrO2 support for the catalytic NO reduction by H2. All of our samples were found to be highly selective, but a significant size effect was not seen for Pd nanoparticles of between 1.2 nm and 5.5 nm. Ultra-small Pd clusters of less than 1 nm were found to be much less active, and are assumed to be affected by an encapsulation effect of the support. Catalyst activity was comparable to that of literature, and is applicable to H2-SCR research.