Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Aragonite; Barium Carbonate; Carbonates; High pressure (Science); Phase transformations (Statistical physics) (1)
- Carbon tetrachloride – Optical properties; Matter — Properties; Nonlinear optics (1)
- Cobalt compounds; Copper compounds; High temperature superconductors (1)
- Crystal lattices; Raman spectroscopy; Spinel group (1)
- Crystals; High pressure (Science); Materials at high temperatures; Niobium compounds (1)
Articles 1 - 8 of 8
Full-Text Articles in Physics
High Pressure Structural Studies On Nb5si3 Up To 26.2 Gpa, Brandon Stewart, Ravhi S. Kumar
High Pressure Structural Studies On Nb5si3 Up To 26.2 Gpa, Brandon Stewart, Ravhi S. Kumar
Undergraduate Research Opportunities Program (UROP)
With the use of synchrotron techniques, we can better understand how crystalline structures behave under extreme conditions. This yields the opportunity to resolve complex crystal structures [1]. Here, we focus on the high pressure crystal structure of Nb5Si3. Refractory metal silicides are an important class of materials as they are used in high temperature applications such as turbines and aerospace modules. As an example, the performance of a jet engine is highly influenced by the maximum internal pressure and temperature possible. Obtaining higher levels of thrust is dependent upon the material's ability to remain structurally sound under extreme temperatures and …
High Pressure Study Of 1,1-Diamino-2,2-Dinitroethene With Raman Spectroscopy, Jack Brangham, Michael Pravica, Martin Galley
High Pressure Study Of 1,1-Diamino-2,2-Dinitroethene With Raman Spectroscopy, Jack Brangham, Michael Pravica, Martin Galley
Undergraduate Research Opportunities Program (UROP)
The goal of this experiment is to better understand the reasons for Fox-7s insensitivity and high performance. It is very similar to other explosives in composition but different in structure. This different structure is believed to be the reason for Fox-7s unique characteristics. Using Raman spectroscopy along with high pressure techniques we hope to better understand this molecule and how it handles extreme conditions.
Ionic Alkalihalides As Pressure Media In Dac Experiments, Julius Monello
Ionic Alkalihalides As Pressure Media In Dac Experiments, Julius Monello
Undergraduate Research Opportunities Program (UROP)
In Diamond Anvil Cells (DACs), usually a pressure transmitting medium functions to transform the uniaxial pressure supplied by the opposing diamond anvils into uniform hydrostatic pressure acting on the sample. Conventionally, a 4-1 methanol-ethanol solution, or a 16-3-1 methanol-ethanol-water solution is used as pressure transmitting medium. However, these two solutions transform into a glass with high elastic shear strength at pressures around 12-14 GPa and no longer function as hydrostatic medium. Our goal was to determine if liquid ionic alkalihalide alkanolate complexes will provide more uniform pressure in the cell up to 20 GPa. Ruby (Cr-doped AlP,) produces two Cr"+ …
Neutron Diffraction Of Nabd4: Phase Transition, Rietveld Structure Refinements, And Equation Of State, Guillermo Esparza, Esparza, Patricia Kalita, Andrew Cornelius
Neutron Diffraction Of Nabd4: Phase Transition, Rietveld Structure Refinements, And Equation Of State, Guillermo Esparza, Esparza, Patricia Kalita, Andrew Cornelius
Undergraduate Research Opportunities Program (UROP)
NaBH4 is a hydride with possible applications as a hydrogen storage material for future renewable energy technologies. It’s dehydrogenation properties are enhanced with the mixture of particular catalysts through ball-milling techniques during which local pressures may exceed several GPa’s. It is for this reason that understanding the behavior of pressure induced phase changes of its crystalline unit cell is an area of interest.
Second Hyperpolarizability Of Carbon Tetrachloride, Phillip C. Lotshaw, Anna M. Smith, David P. Shelton
Second Hyperpolarizability Of Carbon Tetrachloride, Phillip C. Lotshaw, Anna M. Smith, David P. Shelton
Undergraduate Research Opportunities Program (UROP)
Although present theories of nonlinear optics agree with observed behavior in simple atoms such as helium, more complex molecules containing many electrons, such as carbon tetrachloride (CCI4), cannot consistently be described by theory. Through experimental analysis of nonlinear materials, a new, more sophisticated model for describing their properties could be realized. The purpose of our experiment was to measure the nonlinear behavior of the second harmonic signal generated from CCI4 and to compare the results with the prediction by the CCSD(T) molecular model.
Crystal Structural Behavior Of Cocu₂O₃ At High Temperatures, April Jeffries, Ravhi S. Kumar, Andrew L. Cornelius
Crystal Structural Behavior Of Cocu₂O₃ At High Temperatures, April Jeffries, Ravhi S. Kumar, Andrew L. Cornelius
Undergraduate Research Opportunities Program (UROP)
High temperature structure of CoCu₂O₃ The spin ladder compounds have received much attention recently due to their relation to the high transition temperature superconductivity. Also the study of spin ladder compounds is of great interest to explore the specific characteristics that result in their behavior. The CoCu₂O₃ spin ladder crystal structure is similar to SrCu₂O₃, which is apparent composition for many high temperature superconductors. The effects of temperature on structural change are investigated for this system. High temperature x-ray diffraction patterns were collected up to 1000⁰C and the variation of lattice parameters as a function of temperature up to decomposition …
High Pressure Structural Studies On Baco3 Up To 20 Gpa, Justine Carryer, Ravhi S. Kumar
High Pressure Structural Studies On Baco3 Up To 20 Gpa, Justine Carryer, Ravhi S. Kumar
Undergraduate Research Opportunities Program (UROP)
Carbonate compounds are thought to make up a minor portion of the Earth's upper mantel. Shock heating of the surfaces of carbonate rocks, as in the instance of a meteor impact, has the potential to affect CO2 concentrations in the Earth's atmosphere. The bulkmodulus of carbonate materials is directly proportional to the rate of devolatilization under these conditions [1]. The interest in Barium Carbonate (BaCO3) specifically is motivated by its structural proximity to aragonite carbonates. Crystalline phase transitions occur in aragonite under extreme conditions that are difficult to maintain in a laboratory; BaC03 is isostructural with aragonite and therefore is …
Investigation Of Raman Active Modes Of Mgxzn1-Xcr2o4, Nichollas Macholl, Tyler Mosher
Investigation Of Raman Active Modes Of Mgxzn1-Xcr2o4, Nichollas Macholl, Tyler Mosher
Undergraduate Research Opportunities Program (UROP)
Using Raman spectroscopy, vibrational modes of the spinel structure MgxZn1-xCr2O4 were experimentally examined. The spinel compounds were synthesized by producing solid solutions via combustion method, of MgxZn1-xCr2O4 in the range x=0 to x=1 in 0.1 intervals. The purpose of which was to experimentally verify gradual shifts of Raman peaks as the samples transitioned between the two different compounds and gain information about the dependencies of the lattice vibrations on the tetrahedral and octahedral cations. X-ray diffraction was also used to verify spinel structure, and track the changes in lattice parameter of the samples.