Evaluation of tantalum for mercury containment in the SNAP-8 boiler

Corrosion testing of tantalum for mercury containment in SNAP 8 boile

Hydrodynamic Analysis of a Wave Energy Converter (WEC)

Honorable Mention Winner The UNF CREW competing in the U.S. Department of Energy 2021 Marine Energy Collegiate Competition developed a Wave Energy Converter (WEC) for quick deployment in disaster relief areas. When natural disasters disable coastal power grids, a WEC can be easily deployed close to shore and serve as a source of electricity. The ocean waves move magnets through a coil wired within the WEC to generate electricity. To initiate the design process, ANSYS AQWA software simulated both the oceanic environment and the device’s response in the WEC’s testing conditions. AQWA allows the user to change device dimensions easily and optimize the design ahead of physical construction. The resulting WEC proof of concept minimized prototype manufacturing waste and cost by eliminating poor designs in advance. The simulated geometry neglected hollow sections and used unidirectional, regular waves to account for software limitations. The software simulated the WEC for 20 seconds in an oceanic environment with a 40-meter depth and a 0.25-meter amplitude regular wave. Simulations produced graphs and animations describing the forces acting on the WEC as well as the WEC’s movement. The animation proved that the WEC reacts well in similar physical testing conditions. Based on the simulation results, the team constructed a 3D model for small-scale testing. Future investigations will involve more complex designs. Research conducted onward will focus on mass-damper systems and contact surfaces provided in the software

Optimization of Power Performance of a Wave Energy Converter

With climate change on the rise, unprecedented dependence on electricity, and an increased incidence of extreme weather, the UNF team participating in the U.S. Department of Energy 2021 Marine Energy Collegiate Competition: Powering the Blue Economy wants to give an alternative solution to provide renewable energy in areas that lose electricity as a result of a natural disaster, or that due to their isolated location cannot use traditional renewable energy sources. This led to the creation of the Osprey C.R.E.W (Cheap Reliable Energy from Waves). The Osprey C.R.E.W. is a wave energy converter that uses the vertical motion of the ocean waves to generate electricity. The principle of energy conversion is Faraday’s Law of Electromagnetic Induction, which states that a magnetic field moving past a conductor will generate electricity. The UNF team has developed a numerical simulation to test how different parameters influence the output and has built three small-scale prototypes that have been tested in a wave tank. A medium-sized prototype and a wave pool are being constructed, with the expectation that the size will also increase the output

Cost Analysis of Osprey C.R.E.W.

Renewable energy adoption is on the rise in the U.S. and abroad. More than ever, energy sourcing needs to shift away from harmful fossil fuels and towards fully renewable energy sources. Adapting from traditional fossil fuel energy sources to renewable energy sources is paramount for environmental health and public health. Fossil fuels emit harmful pollutants, which have led to changing weather conditions and exasperated natural disasters. Existing renewable sources are not ideal, either. For instance, solar cannot run continuously and wind turbines are subject to weather changes. The recent energy debacle in Texas shows the need for alternative renewable energy sources. The Osprey C.R.E.W. wave energy converter (WEC) alleviates many of the current problems existing renewable energy systems cannot solve. First, it provides reliable and constant service. With other renewable energy services, there will be stops in production. However, there are no stops in wave energy because the waves are constant. Another positive of the WEC device is that their deployments are flexible and scalable. This means that energy production levels can be changed rapidly and without delay. The average cost per device falls significantly with seamless scalability, making large increments of devices procured in a relatively cost-effective manner. Cost comparisons between competing energy sources show that the WEC is very cost-efficient as well. The cost of producing wave energy is found to be more efficient than solar energy and wind alternatives. Our cost figures also show that Osprey C.R.E.W provides a very competitive alternative to the primary fossil fuel producers such as coal and fuel

Constraints on the tectonic and landscape evolution of the Bhutan Himalaya from thermochronometry

The observed geomorphology and calculated thermal histories of the Bhutan Himalaya provide an excellent platform to test ideas regarding the influence of tectonics and climate on the evolution of a convergentmountain range. However, little consensus has been reached regarding the late Cenozoic history of the Bhutan Himalaya. Some researchers have argued that observed geologic relationships show slowing deformation rates, such that the range is decaying from a geomorphic perspective, while others see the range as growing and steepening. We suggest that a better understanding is possible through the integrated interpretation of geomorphic and thermochronometric data from the comparison of predictions from models of landscape evolution and thermal-kinematic models of orogenic systems. New thermochronometric data throughout Bhutan aremost consistent with a significant decrease in erosion rates, from2 to 3 km/Ma down to 0.1–0.3 km/Ma, around 6–4Ma. We interpret this pattern as a decrease in rock uplift rates due to the activation of contractional structures of the Shillong Plateau, an uplifted region approximately 100 km south of Bhutan. However, low-relief, fluvial landscapes throughout the Bhutanese hinterland record a late pulse of surface uplift likely due to a recent increase in rock uplift rates. Constraints from our youngest thermochronometers suggest that this increase in rock uplift and surface uplift occurred within the last 1.75Ma. These results imply that the dynamics of the Bhutan Himalaya and Shillong Plateau have been linked during the late Cenozoic, with structural elements of both regions active in variable ways and times over that interval

Meta-analysis & Review of Learner Performance & Preference: Virtual vs. Optical Microscopy

Background & Purpose: For nearly two decades, a wealth of literature has been published describing the various capabilities, uses, and adaptations of virtual microscopy (VM). Many studies have investigated the effects and benefits of VM on student learning compared to optical microscopy (OM). As such, this study statistically aggregated the findings of multiple comparative studies through a meta-analysis to summarize and substantiate the pedagogical efficacy of teaching with VM. Methods Using predefined eligibility criteria, teams of paired researchers screened the titles and abstracts of VM studies retrieved from seven different databases. After two rounds of screening, numerical and thematic data were extracted from the eligible studies for analysis. A summary effect size and estimate of heterogeneity were calculated to determine the effects of VM on learner performance and the amount of variance between studies, respectively. Trends in student perceptions were also analyzed and reported. Results: Of the 725 records screened, 72 studies underwent full-text review. In total, 12 studies were viable for meta-analysis and additional studies were reviewed to extract themes relating to learners’ perceptions of VM. The meta-analysis detected a small yet significant positive effect on learner performance (SMD=0.28, [CI=0.09, 0.47], p=0.003), indicating that learners experience marked knowledge gains when exposed to VM over OM. Variation among studies was evident as high heterogeneity was reported. An analysis of trends in learner perceptions noted that respondents favored VM over OM by a large margin. Conclusions: Despite many individual studies reporting non-significant findings when comparing VM to OM, the enhanced power afforded by meta-analysis revealed that the pedagogical approach of VM is modestly superior to OM and is preferred by learners

Surface temperature measurements using a thin film thermal array

A thin film device was designed and fabricated to measure surface temperatures. An array of eight integrated thermal sensors are mounted on a 0.002 inch (0.05 mm) Kapton film and multiplexed to obtain an area thermal measurement. The device was tested on a flat plate airfoil and demonstrated a temperature variation of 0.55 C maximum and 0.05 C minimum compared to embedded thermocouples. Future improvements are also discussed

First comparison of French and Australian OsHV-1 µvars by bath exposure

Economically devastating mortality events of farmed and wild shellfish due to infectious disease have been reported globally. Currently, one of the most significant disease threats to Pacific oyster Crassostrea gigas culture is the ostreid herpesvirus 1 (OsHV-1), in particular the emerging OsHV-1 microvariant genotypes. OsHV-1 microvariants (OsHV-1 μvars) are spreading globally, and concern is high among growers in areas unaffected by OsHV-1. No study to date has compared the relative virulence among variants. We provide the first challenge study comparing survival of naïve juvenile Pacific oysters exposed to OsHV-1 μvars from Australia (AUS μvar) and France (FRA μvar). Oysters challenged with OsHV-1 μvars had low survival (2.5% exposed toAUS μvar and 10% to FRA μvar), and high viral copy number as compared to control oysters(100% survival and no virus detected). As our study was conducted in a quarantine facility located~320 km from the ocean, we also compared the virulence of OsHV-1 μvars using artificial seawater made from either facility tap water (3782 μmol kg−1seawater total alkalinity) or purchased distilled water (2003 μmol kg−1). Although no differences in survival or viral copy number were detected in oysters exposed to seawater made using tap or distilled water, more OsHV-1 was detected in tanks containing the lower-alkalinity seawater, indicating that water quality may be important for virus transmission, as it may influence the duration of viral viability outside of the hos

High-impact animal health research conducted at the USDA’s National Animal Disease Center

Commissioned by President Dwight Eisenhower in 1958 and opened with a dedication ceremony in December 1961, the USDA, Agricultural Research Service (ARS), National Animal Disease Center (NADC) celebrated its 50-year anniversary in November 2011. Over these 50 years, the NADC established itself among the world’s premier animal health research centers. Its historic mission has been to conduct basic and applied research on selected endemic diseases of economic importance to the U.S. livestock and poultry industries. Research from NADC has impacted control or management efforts on nearly every major animal disease in the United States since 1961. For example, diagnostic tests and vaccines developed by NADC scientists to detect and prevent hog cholera were integral in the ultimate eradication of this costly swine disease from the U.S. Most major veterinary vaccines for critical diseases such as brucellosis and leptospirosis in cattle, porcine respiratory and reproductive syndrome (PRRS), porcine parvovirus and influenza in swine had their research origins or were developed and tested at the NADC. Additional discoveries made by NADC scientists have also resulted in the development of a nutritional approach and feed additives to prevent milk fever in transition dairy cattle. More recently, NADC’s archive of historic swine influenza viruses combined with an established critical mass of influenza research expertise enabled NADC researchers to lead an effective national research response to the pandemic associated with the novel 2009 H1N1 influenza virus. This review commemorates some of the key animal health contributions in NADC’s first 50 years, recaps the newly completed modernization of the center into new facilities, and offers highlights of the ongoing research that will define NADC’s mission going forward

Gravitational bending of light by planetary multipoles and its measurement with microarcsecond astronomical interferometers

General relativistic deflection of light by mass, dipole, and quadrupole moments of gravitational field of a moving massive planet in the Solar system is derived. All terms of order 1 microarcsecond are taken into account, parametrized, and classified in accordance with their physical origin. We calculate the instantaneous patterns of the light-ray deflections caused by the monopole, the dipole and the quadrupole moments, and derive equations describing apparent motion of the deflected position of the star in the sky plane as the impact parameter of the light ray with respect to the planet changes due to its orbital motion. The present paper gives the physical interpretation of the observed light-ray deflections and discusses the observational capabilities of the near-future optical (SIM) and radio (SKA) interferometers for detecting the Doppler modulation of the radial deflection, and the dipolar and quadrupolar light-ray bendings by the Jupiter and the Saturn.Comment: 33 pages, 10 figures, accepted to Phys. Rev.