447 research outputs found
Correspondence - Attie Bostick Feb. 23, 1934 - Wade Bostick
A correspondence from Attie T. Bostick. Includes handwritten note to Mrs. H.L. Packard and a partial letter from Wade Bostick.https://digitalcommons.gardner-webb.edu/baptist-historical-collections-bostick-family-missions/1019/thumbnail.jp
Electroreduction and photometric detection of low-level uranium in aqueous Purex solutions. Consolidated Fuel-Reprocessing Program
During proper operation of the Purex process for the recovery of uranium and plutonium from spent reactor fuel, there are only trace levels of uranium in the aqueous waste. In the event of an upset in the extraction columns the aqueous waste stream would give the first indication of breakthrough. From the standpoint of process control it would be desirable to have an in-line, real-time sensor for uranium in the aqueous waste stream. It was toward this end that this investigation was undertaken. The measurement technique that seems to provide the most sensitive method without addition of reagents appears to be the electrochemical reduction of UO{sub 2}{sup 2+} to U(IV) followed by spectral measurement. The electrochemical reduction to U(IV) increases the sensitivity by a factor of three to five and shifts the measurement wavelength to a spectral area (647 nm and 1075 nm) unaffected by fission products. Using the proposed analysis sequence it is possible to determine uranium at a level of 0.2 g/L in the presence of relatively high spectral background. This report details the electrochemical reduction of U(VI) in nitric acid solutions (0.5 M to 2.0 M) with platinum-vitreous carbon electrodes and examines the spectral behavior of U(IV) as a function of nitric acid concentration
Wax Point Determinations Using Acoustic Resonance Spectroscopy
The thermodynamic characterization of the wax point of a given crude is essential in order to maintain flow conditions that prevent plugging of undersea pipelines. This report summarizes the efforts made towards applying an Acoustic Cavity Resonance Spectrometer (ACRS) to the determination of pressures and temperatures at which wax precipitates from crude. Phillips Petroleum Company, Inc., the CRADA participant, supplied the ACRS. The instrumentation was shipped to Dr. Thomas Schmidt of ORNL, the CRADA contractor, in May 2000 after preliminary software development performed under the guidance of Dr. Samuel Colgate and Dr. Evan House of the University of Florida, Gainesville, Fl. Upon receipt it became apparent that a number of modifications still needed to be made before the ACRS could be precisely and safely used for wax point measurements. This report reviews the sequence of alterations made to the ACRS, as well as defines the possible applications of the instrumentation once the modifications have been completed. The purpose of this Cooperative Research and Development Agreement (CRADA) between Phillips Petroleum Company, Inc. (Participant) and Lockheed Martin Energy Research Corporation (Contractor) was the measurement of the formation of solids in crude oils and petroleum products that are commonly transported through pipelines. This information is essential in the proper design, operation and maintenance of the petroleum pipeline system in the United States. Recently, new petroleum discoveries in the Gulf of Mexico have shown that there is a potential for plugging of undersea pipeline because of the precipitation of wax. It is important that the wax points of the expected crude oils be well characterized so that the production facilities for these new wells are capable of properly transporting the expected production. The goal of this work is to perform measurements of solids formation in crude oils and petroleum products supplied by the Participant. It is anticipated that these data will be used in the design of new production facilities and in the development of thermodynamic models that describe the behavior of wax-saturated petroleum
Design of Microwave Vitrification Systems for Radioactive Waste
Oak Ridge National Laboratory (ORNL) is involved in the research and development of high-power microwave heating systems for the vitrification of DOE radioactive sludges. Design criteria for a continuous microwave vitrification system capable of processing a surrogate filtercake sludge representative of a typical waste-water treatment operation are discussed. A prototype 915 MHz, 75 kW microwave vitrification system or `microwave melter` is described along with some early experimental results that demonstrate a 4 to 1 volume reduction of a surrogate ORNL filtercake sludge
Fundamental Concepts of Cyber Resilience: Introduction and Overview
Given the rapid evolution of threats to cyber systems, new management
approaches are needed that address risk across all interdependent domains
(i.e., physical, information, cognitive, and social) of cyber systems. Further,
the traditional approach of hardening of cyber systems against identified
threats has proven to be impossible. Therefore, in the same way that biological
systems develop immunity as a way to respond to infections and other attacks,
so too must cyber systems adapt to ever-changing threats that continue to
attack vital system functions, and to bounce back from the effects of the
attacks. Here, we explain the basic concepts of resilience in the context of
systems, discuss related properties, and make business case of cyber
resilience. We also offer a brief summary of ways to assess cyber resilience of
a system, and approaches to improving cyber resilience.Comment: This is a preprint version of a chapter that appears in the book
"Cyber Resilience of Systems and Networks," Springer 201
Distinct degassing pulses during magma invasion in the stratified Karoo Basin â New insights from hydrothermal fluid flow modelling
Magma emplacement in organicârich sedimentary basins is a main driver of past environmental crises. Using a 2D numerical model, we investigate the process of thermal cracking in contact aureoles of cooling sills and subsequent transport and emission of thermogenic methane by hydrothermal fluids. Our model includes a MohrâCoulomb failure criterion to initiate hydrofracturing and a dynamic porosity/permeability. We investigate the Karoo Basin, taking into account hostârock material properties from borehole data, realistic total organic carbon content, and different sill geometries. Consistent with geological observations, we find that thermal plumes quickly rise at the edges of saucerâshaped sills, guided along vertically fractured high permeability pathways. Contrastingly, less focused and slower plumes rise from the edges and the central part of flatâlying sills. Using a novel upscaling method based on sillâtoâsediment ratio we find that degassing of the Karoo Basin occurred in two distinct phases during magma invasion. Rapid degassing triggered by sills emplaced within the top 1.5 km emitted ~1.6·103 Gt of thermogenic methane, while thermal plumes originating from deeper sills, carrying a 12âtimes greater mass of methane, may not reach the surface. We suggest that these large quantities of methane could be reâmobilized by the heat provided by neighboring sills. We conclude that the Karoo LIP may have emitted as much as ~22.3·103 Gt of thermogenic methane in the half million years of magmatic activity, with emissions up to 3 Gt/year. This quantity of methane and the emission rates can explain the negative ÎŽ13C excursion of the Toarcian environmental crisis.
Key Points
Sill geometry and emplacement depth as well as intruded host rock type are the main factors controlling methane mobilization and degassing
Dehydrationârelated porosity increase and poreâpressureâinduced hydrofracturing are important mechanisms for a quick transport of methane from sill to the surface
The Karoo Basin may have degassed ~22.3·103 Gt of thermogenic methane in the half million years of magmatic activit
The development of a stakeholder-endorsed national strategic plan for advancing pain education across Canadian physiotherapy programs
Abstract
Background
The Canadian Pain Task Force recently advanced an action plan calling for improved entry-level health professional pain education. However, there is little research to inform the collaboration and coordination across stakeholders that is needed for its implementation.
Aims
This manuscript reports on the development of a stakeholder-generated strategic plan to improve pain education across all Canadian physiotherapy (PT) programs.
Methods
Participants included representatives from the following stakeholder groups: people living with pain (n = 1); PT students and recent graduates (n = 2); educators and directors from every Canadian PT program (n = 24); and leaders of Canada?s national PT professional association (n = 2). Strategic priorities were developed through three steps (1) stakeholder-generated data was collected and analyzed; (2) a draft strategic plan was developed and refined; and (2) stakeholder endorsement of the final plan was assessed. The project was primarily implemented online, between 2016 and 2018.
Results
The plan was developed through five iterative versions. Stakeholders unanimously endorsed a plan that included five priorities focusing on uptake of best evidence across (1) national PT governance groups and (2) within individual PT programs; (3) partnering with people living with pain in pain education; (4) advocacy for the PT role in pain management; and (5) advancing pain education research.
Conclusion
This plan is expected to help Canadian stakeholders work toward national improvements in PT pain education and to serve as a useful template for informing collaboration on entry-level pain education within other professions and across different geographic regions
Voltage-Gated Ion Channel Dysfunction Precedes Cardiomyopathy Development in the Dystrophic Heart
Duchenne muscular dystrophy (DMD), caused by mutations in the dystrophin gene, is associated with severe cardiac complications including cardiomyopathy and cardiac arrhythmias. Recent research suggests that impaired voltage-gated ion channels in dystrophic cardiomyocytes accompany cardiac pathology. It is, however, unknown if the ion channel defects are primary effects of dystrophic gene mutations, or secondary effects of the developing cardiac pathology.To address this question, we first investigated sodium channel impairments in cardiomyocytes derived from dystrophic neonatal mice prior to cardiomyopahty development, by using the whole cell patch clamp technique. Besides the most common model for DMD, the dystrophin-deficient mdx mouse, we also used mice additionally carrying an utrophin mutation. In neonatal cardiomyocytes, dystrophin-deficiency generated a 25% reduction in sodium current density. In addition, extra utrophin-deficiency significantly altered sodium channel gating parameters. Moreover, also calcium channel inactivation was considerably reduced in dystrophic neonatal cardiomyocytes, suggesting that ion channel abnormalities are universal primary effects of dystrophic gene mutations. To assess developmental changes, we also studied sodium channel impairments in cardiomyocytes derived from dystrophic adult mice, and compared them with the respective abnormalities in dystrophic neonatal cells. Here, we found a much stronger sodium current reduction in adult cardiomyocytes. The described sodium channel impairments slowed the upstroke of the action potential in adult cardiomyocytes, and only in dystrophic adult mice, the QRS interval of the electrocardiogram was prolonged.Ion channel impairments precede pathology development in the dystrophic heart, and may thus be considered potential cardiomyopathy triggers
Modern Electronic Techniques Applied to Physics and Engineering
Contains reports on five research projects
Modern Electronic Techniques Applied to Physics and Engineering
Contains reports on seven research projects.Office of Scientific Research and Development (OSRD) OEMsr-26
- âŠ