LOUIS University of Alabama in Huntsville
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Generation and Curation of a Reference Sequence Database for Groundwater Organisms
Get PDFhttps://louis.uah.edu/rceu-hcr/1448/thumbnail.jp
Optimizing a Method for Investigating the Role of P75NTR in Neurodegeneration Associated with Parkinson\u27s Disease
Get PDFhttps://louis.uah.edu/rceu-hcr/1453/thumbnail.jp
Called to Care: Faith-based AIDS Responses in 1980s and 1990s Alabama
Get PDFhttps://louis.uah.edu/rceu-hcr/1474/thumbnail.jp
Liner implosion of magneto-inertial fusion plasmas across the periodic table
Get PDFThe goal of achieving net energy production from fusion reactions would have many positive and transformational impacts upon society and is therefore of great interest. Magneto-Inertial Fusion may be a path to achieving the high energy density requirements. One possible method for reaching the necessary plasma conditions is through a z-pinch driving a magnetized liner to compress and heat the fusion fuel. Progress has been made through both modeling and experiment, largely through Sandia National Laboratories, in recent years in developing this process and achieving neutron yields in the range of 1013 neutrons per pulse. Magnetized liner z-pinch experiments have largely used beryllium liners. This is in part because materials adjacent to the fuel will mix during the implosion and reduce yield. Higher atomic number materials are also more inclined to radiation energy loss due to higher rates of bremsstrahlung radiation. However, alternate materials may have advantages to the implosion or in the context of a wider system level design. This work seeks to investigate several materials across the periodic table in the context of a magnetized liner z-pinch implosion. This work investigates the implosion dynamics and resulting thermodynamic conditions and yield. The work presented uses a smooth particle hydrodynamic method in a newly developing multi physics code that solves the resistive magnetohydrodynamic equations with a tabular equation of state and transportation models (e.g., radiation, electron thermal conduction, neutron, and fusion reactions). This work has found similar dynamic structures in the liner across materials and driving currents that agree with existing literature. The z-pinches are dominated by large wavelength Rayleigh-Taylor instabilities on the order of 1 to 3 mm with amplitudes reaching similar values around 1 to 2 mm. Liner areal densities are found to reach 0.025 and 0.8 g/cm2 for 4 and 16 MA peak cases. With a constant liner mass at a given driving current, timing of stagnation deviates in some cases up to approximately 25 ns due to the characteristic properties of the liner materials. Changing liner material results in a changing equation of state and resulting material properties leading to altered implosion dynamics. The baseline model in this work reaches a similar temperature of approximately 1.8 keV to that of a reference 16 MA peak current z-pinch experiment at Sandia National Laboratories. The corresponding pressure and neutron yield are an order of magnitude less than the referenced experiment at about 1 terapascal and 1011 neutrons while confinement time is found to be similar at about 2 ns. Fuel density in the baseline model is found to peak at about 1000 kg/m3. As liner materials were changed to gallium and tungsten, peak temperature in the model was seen to drop to 0.8 and 0.6 keV respectively while peak density reached 500 and 300 kg/m3 respectively. Peak pressure for the gallium case was similar at 1 terapascal while tungsten reached a higher peak pressure of 4.5 terapascal. The confinement times were of a similar magnitude of about 1.6 and 1.25 ns while neutron yields were similar at 4x1011 and decreased to 7.5x109 for gallium and tungsten respectively. The model was also extended to a 4 MA peak current case with the same time to peak current of 100 ns. Temperatures were found to peak at 1, 0.5, and 0.7 keV, densities peaked at 25, 3.5, and 10 kg/m3, and pressures peaked at 0.3, 0.14, and 0.45 terapascal for beryllium, gallium and tungsten respectively. The neutron yields were found to drop to 3x109, 1.5x109, and 1.5x109 while burn durations were found to be about 4.4, 2.7, and 3.75 ns for beryllium, gallium, and tungsten respectively
Aerodynamic losses of additively manufactured blades in transonic conditions with different surface treatments
Get PDFAdditive manufacturing (AM) allows the production of high strength and high temperature alloys to increase the operational temperature of turbines and other engine components. AM inherently has high surface texturing, inclusive of waviness due to the layering effect in the laser powder bed fusion (L-PBF) process, and roughness due to surface defects such as partially sintered powder, deep notches, and micro-cracks. This thesis investigates how different surface treatments affect the surface static pressure variations and wake aerodynamic loss characteristics for each blade. A supersonic transonic blow down wind tunnel with a linear cascade test section is used to acquire this experimental data. Each blade is instrumented with 22 pressure taps along the 50% to measure surface static pressure, while a motorized traverse sweeps a pitot static pressure probe through the wake 0.25Cx downstream of the cascade. Downstream wake aerodynamic profiles for the blades with lower magnitudes of surface roughness evidence larger magnitudes of loss parameters, which are spread over larger areas, compared to distributions associated with higher roughness configurations. Blade wakes associated with higher Ra and ks/Cx values are also generally asymmetric and additionally experience a lower decrease in local Mach number throughout the wake
Importance of Uncertainty Quantification in Rocket Engine Development using Additive Manufacturing and its Implementation using MBSE
Get PDFhttps://louis.uah.edu/research-horizons/1352/thumbnail.jp
Importance of Uncertainty Quantification in Rocket Engine Development using Additive Manufacturing and its Implementation using MBSE
Get PDFhttps://louis.uah.edu/research-horizons/1368/thumbnail.jp
Increasing the uptake of palliative care for patients with COPD through community-based referrals : a clinical practice change
No full textThere are 251 million people diagnosed with chronic obstructive pulmonary disease (COPD) and 3.3 million deaths annually linked to disease-related complications. Palliative care is an underutilized resource for a patient with COPD. It can help establish goals of care, manage disease-related symptoms, and improve quality of life. Rural hospitals often face barriers to accessing palliative care services, including a lack of healthcare providers, means of transportation, and stigma surrounding the holistic health model. This DNP project aimed to generate appropriate community-initiated palliative care referrals to increase service uptake and reduce readmissions within 30 days of discharge. Patients with COPD who were 55 years and older were screened using the Palliative Care Screening Tool to determine if the patient met criteria for a palliative care referral. The project was implemented on a 30-bed medical-surgical unit in an 80-bed rural hospital in the Panhandle of Florida. The clinical practice change project set new unit protocols to determine if appropriate palliative care referrals increase the uptake of community-initiated palliative care services. Registered nurses and unit case managers used evidence-based practices to screen and identify appropriate palliative care referrals using the Palliative Care Screening Tool to initiate community-based referrals and increase the uptake of palliative care services to reduce the number of patients with COPD who present to the emergency department for disease-specific care. Following the implementation, the uptake of community-based palliative care services decreased readmissions within 30 days of discharge for an acute COPD exacerbation. During the implementation of the clinical practice change, readmissions for patients with COPD within 30 days of discharge declined by 13%. Since readmissions remain a huge concern for healthcare organizations, incorporating a tool to assess the need for palliative care could catalyze the improvement of quality care for patients with chronic illnesses in rural communities