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Session G: Nuclear Power/Climate Change – TerraPower’s Traveling Wave Reactor
No full textTyler Ellis is a project manager for TerraPower, where he works on developing and deploying new nuclear generating capacity to meet current and future energy needs. Before working at TerraPower, Ellis worked as a reactor supervisor at the Massachusetts Institute of Technology (MIT) Nuclear Reactor Laboratory and as a nuclear engineer for the MIT Center for Advanced Nuclear Energy Systems.
In 2007, Ellis worked with other MIT thought leaders to help shape the overall plan for the highly successful Bernard M. Gordon MIT Engineering Leadership Program. He composed plant design requirements for a high-temperature gas-cooled reactor with AREVA in France; conducted neutronic trade studies for three different nuclear electric propulsion systems at the Los Alamos National Laboratory; and explored economic, social and technical complexities in meeting the sustainability challenge in Switzerland.
Ellis earned both bachelors and master’s degrees in 2006 from the Massachusetts Institute of Technology in the field of nuclear science and engineering. In 2008, he earned his doctorate from MIT in the same field specializing in reactor physics. In addition, Ellis won several Best Technical Session awards for reactor physics at the American Nuclear Society student conferences. He was recognized by Scientific American as a Distinguished Scholar, received the American Nuclear Society John R. Lamarsh Memorial Award and was officially commended by the governor of California. In addition to having received several other awards, he is author/co-author of more than 15 publications and technical reports.TerraPower is moving forward with detailed plans for a sustainable, economic, and safe nuclear reactor. The Travelling Wave Reactor (TWR) – a reactor in the 500-megawatt electric range – uses unique core physics to initiate a breed and burn wave which can be completely sustained in fertile material. This process allows the TWR to convert depleted uranium waste into usable fuel as the reactor operates, providing a sustainable base-load power source. TerraPower is the first company to create a practical engineering embodiment of this previously studied concept thanks to a powerful advanced reactor modeling interface, developed in-house, which enables the analysis of traveling wave reactor technology in a way that has not been possible before. This presentation will provide more detail about the origins of the TWR, the project’s current status as well as some of the safety differences between TWRs and currently operating light water reactors
Ray, G. Thomas, Aesthetics and Phenomenology of Learning: Rejecting the Tyler Rationale, Educational Forum, 53(Winter, 1989), 127-134.*
No full textCritiques the Tyler rationale in terms of recent non-positivist perspectives; followed by Tyler\u27s response and the author\u27s rejoinder
High rate anaerobic digestion of primary and secondary sludge using the static granular bed reactor (SGBR)
Get PDFThe aim of this research was to demonstrate the feasibility of the static granular bed reactor (SGBR) as a replacement for the conventional mixed and heated anaerobic digester typically operating at municipal wastewater treatment plants (WWTP). The static granular bed reactor (SGBR) is a high rate anaerobic granular reactor. The SGBR operates at a short hydraulic retention time (HRT) (i.e 1 to 2 d) while maintaining a long solids retention time (SRT). Conversely to conventional digesters the SGBR separates the SRT from the HRT, reducing energy and volume requirements. The SGBR is downflow reactor with a dense bed of granules that entraps particles which helps to facilitate hydrolysis. Anaerobic treatment of primary and secondary municipal sludge was studied with a laboratory and pilot-scale SGBR at organic loading rates (OLR) from 2.8 ± 0.9 to 5.5 ± 1.7 g COD/L·d and 3.3 ± 2.0 g COD/L·d, respectively. The results of this research demonstrated the SGBR system's potential to be a practical and competitive alternative to conventional anaerobic digestion of wastewater sludges. The laboratory (76 ± 4%) and pilot-scale (71 ± 0.4%) SGBR produced a biogas with a higher methane content than the conventional anaerobic digester tested (59 ± 2.8%). Effluent VFA concentrations remained below 40 mg/L as HAc, indicating the potential to reduce process instability due to the buildup of intermediates. The low VFA concentrations of the SGBR's effluent also reduces odors compared to the liquid streams of conventional anaerobic digesters. The SGBR produced an effluent with low organic matter; average TSS and COD removal efficiencies remained above 90%.</p
Hydrothermal Synthesis and Characterization of Novel Thorium, Uranium, and Neptunium Solids
Get PDFHydrothermal synthesis has been utilized to synthesize several compounds involving thorium, uranium, and neptunium. These compounds have one-, two-, and three-dimensional structural typologies. A majority of the compounds reported are strictly inorganic in composition; however, some examples of solids with the incorporation of organic molecules are reported. The compounds reported consist of thorium(IV) selenites, selenates, chromates, tellurates, and iodates, uranium(VI) periodates, transition metal uranium(IV) fluorides, and neptunium(IV) fluorides. The structural characteristics of these molecules augment the knowledge base of the chemical complexity of these early actinide elements. All structures were delineated through the use of single crystal X-ray diffraction with the aid of EDAX and IR analysis. Structure
properties of the synthetic phases were examined as necessary. These structural aspects include second-harmonic generation of light and ion exchange. Examples of open-framework and channel structures are also reported
The Impact of Resistance Exercise on Neurotransmission Failure within Trained Participants
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Interactions between visual and semantic processing during object recognition revealed by modulatory effects of age of acquisition
Get PDFThe age of acquisition (AoA) of objects and their names is a powerful determinant of processing speed in adulthood, with early-acquired objects being recognized and named faster than late-acquired objects. Previous research using fMRI (Ellis et al., 2006. Traces of vocabulary acquisition in the brain: evidence from covert object naming. NeuroImage 33, 958–968) found that AoA modulated the strength of BOLD responses in both occipital and left anterior temporal cortex during object naming. We used magnetoencephalography (MEG) to explore in more detail the nature of the influence of AoA on activity in those two regions. Covert object naming recruited a network within the left hemisphere that is familiar from previous research, including visual, left occipito-temporal, anterior temporal and inferior frontal regions. Region of interest (ROI) analyses found that occipital cortex generated a rapid evoked response (~ 75–200 ms at 0–40 Hz) that peaked at 95 ms but was not modulated by AoA. That response was followed by a complex of later occipital responses that extended from ~ 300 to 850 ms and were stronger to early- than late-acquired items from ~ 325 to 675 ms at 10–20 Hz in the induced rather than the evoked component. Left anterior temporal cortex showed an evoked response that occurred significantly later than the first occipital response (~ 100–400 ms at 0–10 Hz with a peak at 191 ms) and was stronger to early- than late-acquired items from ~ 100 to 300 ms at 2–12 Hz. A later anterior temporal response from ~ 550 to 1050 ms at 5–20 Hz was not modulated by AoA. The results indicate that the initial analysis of object forms in visual cortex is not influenced by AoA. A fastforward sweep of activation from occipital and left anterior temporal cortex then results in stronger activation of semantic representations for early- than late-acquired objects. Top-down re-activation of occipital cortex by semantic representations is then greater for early than late acquired objects resulting in delayed modulation of the visual response
A narrative of the Indian and civil wars in Virginia : in the years 1675 and 1676 /
No full textReprint, without acknowledgment, from Force tracts, v. 1 (1836) no. 11.Caption title : Colonial tracts, vol. I, no. 10.Moses Coit Tyler, in his History of American literature, expresses the opinion that the author was one Cotton of Aquia Creek, husband of that Mrs. Cotton who wrote "An account of our late troubles".On verso of t.-p. : Colonial tracts, no. 10.Mode of access: Internet
Metaphor For a Post-White Horizon
Get PDFThis project is a counternarrative, in the tradition of Richard Delgado’s The Rodrigo Chronicles, using critical race theory’s storytelling methodology. We present a discussion between a Black scholar and white scholar sharing their experiences as they explore the relationship between Blackness/whiteness and anti-Blackness/white supremacy. The crux of this counternarrative lies in the intersection between the hopelessness one Black scholar feels toward racial progress in America and the desperation of a white scholar as they process the possibilities for a post-white ontological future within the Western academy in the wake of the January 6th Insurrection. The counter-story integrates Afropessimistic thought with the creativity of Afrofuturism to comment on the uses and abuses of Black labor under the white gaze. The conclusion of the counter-story argues for the need of a post-white futurism that imagines a possible future without whiteness and a future that is also not subsistent upon the foundational abuse and overuse of Black labor.
Corresponding author information:
Dwayne Kwaysee Wright, J.D., Ph.D., Assistant Professor of Higher Education Administration, The George Washington University, 2136 G Street NW, Room 118, Washington, DC 20052, [email protected], Phone: 347.291.6276
Biographies
Dwayne Kwaysee Wright (he/him/his), J.D., Ph.D. is an Assistant Professor of Higher Education and Director of Diversity, Equity, and Inclusion Initiatives at the Graduate School of Education and Human Development which is part of the George Washington University. His research and social activism seek to advance educational opportunity and equity for all students, particularly those historically oppressed and marginalized in American society.
Email: [email protected]
Dr. Tyler Derreth (he/him/his) is the associate director of SOURCE and faculty in the Department of Health, Behavior, and Society at Johns Hopkins University. His research concentrates on urban community–university partnerships, critical pedagogies, and equitable educational practices. He centers his research agenda on issues of social justice, racism, and identity.
Email: [email protected]
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