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Title: Physicochemical Characterization of the SiC Barrier Layer of Irradiated TRISO Fuel
Creator: Seibert, Rachel
Date: 2018
Description: Tristructural-isotropic (TRISO) nuclear fuel is designed to be an inherently safe microencapsulated fuel for use in advanced nuclear reactors...
Show moreTristructural-isotropic (TRISO) nuclear fuel is designed to be an inherently safe microencapsulated fuel for use in advanced nuclear reactors. TRISO fuel is comprised of an uranium-carbide/uranium-oxide mixed kernel, surrounded subsequently by a porous carbon buffer layer, pyrolytic carbon, silicon carbide, and pyrolytic carbon. The silicon carbide layer acts as both the structural backbone and the main barrier to non-gaseous fission product release from the kernel. During operation, fission products are known to release from intact fuel (silver) and to locally corrode the silicon carbide layer (palladium). Release of silver can pose a threat to safety and maintenance workers due to plate-out on reactor components, while palladium corrosion leads the possibility of failure of the SiC layer. An understanding of the silver release mechanism, the diffusion of palladium and fuel kernel components, and their possible correlation is necessary to understand envelopes for safe operation using these fuels.This work focuses on analysis of the reactivity of silver, palladium, and fissile inventory with silicon carbide to determine potential mechanisms and interactions. Irradiated TRISO particles and model thin film cubic silicon carbide (3C-SiC) surfaces were studied to compare and understand the reaction mechanisms of these fission products. Analysis on both systems involved X-ray Absorption Fine Structure Spectroscopy (XAFS) measurements to determine the local atomic structure of the bulk material and electron microscopy studies to observe the microstructure and fission product location. Additionally, x-ray photoelectron spectroscopy (XPS) was used to study the fundamental surface science of silver and palladium in the 3C-SiC thin films. From the comparative studies in this work, the interaction of silver, palladium, and fuel kernel products has been observed. Palladium silicides are preferentially formed, but silver remains metallic and diffuses through both bulk SiC, through material defects, and through grain boundary diffusion. Uranium preferentially forms carbides with increasing temperature. Plutonium primarily forms silicides, but with short carbon bonds. All fission products and fissile inventory were observed to be segregated along grain boundaries in the SiC. This work did not measure a single release mechanism, but suggests multiple mechanisms work together simultaneously. It also presents the first evidence of uranium carbide formation at elevated temperatures and of silver as a metal in irradiated TRISO fuel, to the best of the author's knowledge.
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Title: Enhancing Charge/Discharge Cycle Stability of NaCrO2 Cathode for Na-ion Batteries via Carbon Coatings
Creator: Shi, Zhepu
Date: 2018
Description: In this study, we report the effects of carbon coating on the electrochemical cycle stability of Na-ion batteries made of NaCrO2 cathodes....
Show moreIn this study, we report the effects of carbon coating on the electrochemical cycle stability of Na-ion batteries made of NaCrO2 cathodes. Various coating approaches and conditions have been investigated for 10-h high energy ball milled NaCrO2. It is shown that mixing the carbon source with NaCrO2 particles before the high-temperature carbonization reaction is a critical step. The solution-based mixing of the carbon source with NaCrO2 leads to the best carbon coating uniformity. Furthermore, carbonization treatment should be limited to 10 min at 650 ℃ in order to prevent the reaction between carbon and NaCrO2 to form chromium carbides. Uniform carbon coating can improve the capacity retention of NaCrO2 over charge/discharge cycles and the best capacity retention achieved in this study is 70% after 50 cycles. Furthermore, once the coating is uniformly distributed, NaCrO2 exhibits a very high specific capacity (140 mAh/g) which is significantly higher than the typical value of 110 mAh/g reported in the literature. The unusually high specific capacity observed is attributed to the enhancement of Na-ion intercalation and de-intercalation rates at the electrode/electrolyte interface because of the presence of the carbon coating.
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Title: Electron Cloud studies at Fermilab
Creator: Ji, Yichen
Date: 2019
Description: The presence of unwanted electrons in an accelerator vacuum chamber, known as E-cloud (E-cloud) can potentially cause operational problems in...
Show moreThe presence of unwanted electrons in an accelerator vacuum chamber, known as E-cloud (E-cloud) can potentially cause operational problems in the Fermilab Main Injector (MI) and Recycler Ring (RR). E-cloud has caused instability in the RR in the past, and although it is not currently a problem, there is measurable E-cloud in the MI accelerator. There are planned beam intensity increases due to upgrades of the Fermilab accelerator complex, so E-cloud could become a problem. Some work has been done by others previously to understand how low SEY (Secondary Electron Yield coefficient) coatings might mitigate production of E-cloud, and to model the mechanism whereby E-cloud causes beam instability. Using previous studies as a base, this research took several approaches toward understanding the risk of E-cloud at Fermilab. The evolution of the SEY of the SS316L (stainless steel), TiN coated SS316L, and amorphous carbon coated SS316L were measured in-situ using a SEY measurement station in the MI tunnel. The SEY of these materials change over time either due to bombardment of the E-cloud, or disruption of vacuum conditions. The SEY evolution was tracked over a several year period to find out how long it takes for the SEY of each material to reach its lowest level, and how much the SEY rises during deconditioning periods of poor vacuum. The SEY measurement results can be used to determine whether the SS316L will be a problem at upgrade intensities, and if so, whether or not TiN and A-Carbon coatings can mitigate E-cloud related problems sufficiently. Direct measurements of the E-cloud were done as well, and compared to simulation. The E-cloud bombardment rate was measured at different beam intensities and bunch lengths. It was possible to get detailed information on how the E-cloud varies over the acceleration cycle, where sensitivity to bunch length is reflected in the evolution of the E-cloud. The Retarding Field Analyzer (RFA) measuring the E-cloud bombardment rate was near the instrument that is used to measure the SEY of the beam pipe material. This proximity provided an accurate SEY value for simulations, so that the simulated E-cloud bombardment rate could be better compared to measurement. Bunch length measurements and computations generated accurate bunch length information also needed as input for simulations. After this careful control of the input parameters, the POSINST simulations of E-cloud were a good match to direct measurements. This gave confidence that predictions could be made concerning the E-cloud densities at upgrade intensities. These densities were compared against corresponding proton densities to predict the SEY required to avoid instabilities. That prediction and the information provided by the SEY measurements provide helpful information regarding the risks of E-cloud effects at future beam intensities at Fermilab.
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Title: Capillary Rise of Common Liquids and Nanofluids: Experiments and Modeling
Creator: Wu, Pingkeng
Date: 2018
Description: Capillary dynamics of common liquids and nanofluids is a ubiquitous everyday phenomenon. It has practical applications in diverse fields,...
Show moreCapillary dynamics of common liquids and nanofluids is a ubiquitous everyday phenomenon. It has practical applications in diverse fields, including ink-jet printing, lab-on-a-chip, biotechnology, and coating. Important as it is, this phenomenon has not been fully understood and requires tremendous effort in theoretical analysis and experimental investigations to gain further knowledge and guide the design of practical precesses whenever capillarity is essential.The rise of the main meniscus in rectangular capillaries is important in interpreting the phenomenon of fluid flow in porous media. This thesis presents an experimental study on the rise of the main meniscus in rectangular borosilicate glass and plastic (polystyrene) capillaries using three different liquids (water, ethanol, and hexadecane). A universal model (an extended two-wall model) based on the Laplace equation was developed to predict the equilibrium height of the main meniscus in rectangular capillaries. In capillary dynamics, it is crucial to understand the interaction between fluid molecules and a solid substrate (the wall) in molecular scale. Recent studies reveal that a layered molecularly thin wetting film (LMTWF) will develop ahead of the apparent three-phase contact line for the spreading of a wetting liquid on solid surfaces. Based on this fact, a novel molecular self-layering model is proposed to explain the dynamic wetting considering the role of the molecular shape on self-layering and its effect on the molecularly thin film viscosity in regards to the advancing (dynamic) contact angle. The proposed molecular self-layering model is then incorporated into the Lucas-Washburn-Rideal (LWR) equation to explain the capillary rise dynamics of fluids of spherical, cylindrical, and disk shape molecules in borosilicate glass capillaries. The abilities of the other popular dynamic contact angle models to correct the dynamic contact angle effect in the capillary rise process were also investigated. The LWR equation modified by molecular self-layering model predicts well the capillary rise of carbon tetrachloride, octamethylcyclotetrasiloxane and n-alkanes with the molecular diameter or measured solvation force data. The molecular self-layering model modified LWR equation also has good predictions on the capillary rise of silicone oils covering a wide range of bulk viscosities with the same key parameter W(0), which results from the molecular self-layering. Besides the open capillaries, the proposed molecular self-layering model is applied to explain the spontaneous rise of Newtonian liquids in closed-end capillaries. Contribution of the compressed air inside the closed capillaries is also modeled and experimentally verified. Finally, the research is extended to a liquid phase displacing another immiscible liquid in capillaries with the focus on surfactant solutions containing polymeric nanoparticles (nanofluids), which have been shown to have an improved wetting and spreading on solid surfaces. The polymeric nanoparticles can reduce the frictional coefficient by as much as four times by forming structured layers in the confined wedge film. The role of the interfacial tension on the frictional coefficient is also demonstrated.In summary, this thesis presents the physics of liquid rise in rectangular capillaries, effect of molecular self-layering in capillary dynamics in open and closed-end capillaries, and the contribution of nanofluids in the two-phase displacement dynamics.
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Title: Intraoperative tumor margin detection using nanoparticles: protocol optimization through kinetic modeling
Creator: Xu, Xiaochun
Date: 2018
Description: Clear margins (no tumor on the surface of the resected tissues) is essential to minimize tumor recurrence and prolong survival for wide local...
Show moreClear margins (no tumor on the surface of the resected tissues) is essential to minimize tumor recurrence and prolong survival for wide local excision cancer surgeries. However, standard methods of margin assessment cannot be carried out within the time frame of surgery (meaning patients with positive margins are suggested to undergo call-back surgeries). Intraoperative molecular imaging of cell surface receptors can offer a solution; however, substantial nonspecific diffusion and retention of imaging agents in resected tissues remains a significant challenge to identifying cancer reliably. Recently, “paired-agent” methods—which employ co-administration of a control-imaging agent with a targeting agent—have been applied to thick-sample staining and rinsing applications to account for background staining. This dissertation aimed to optimize paired-agent molecular imaging tumor-to-healthy tissue discrimination through mathematical modeling.Two simplified mathematical models—the rinsing paired-agent model (RPAM) and the serial staining model (SSM)—were derived and tested in accurate simulation models (also developed as a component of this dissertation,) and in preclinical cancer models. More specifically, RPAM was demonstrated to be capable of providing more accurate estimates of receptor concentration than more standard “ratiometric” methods (essentially dividing the targeted agent signal by the control agent signal), and the model was insensitive to the variability of rinsing time from one image to the next. Though it was noted in experiments, that regardless of the approach taken, a very large fraction of signal was removed upon the first rinse, leading to large “gaps” in the data that would be available to RPAM. The SSM, on the other hand, provided a model that could be applied to serial staining data, which yielded a more gradual change in signal between imaging.Considering the multidimensional complexity of paired-agent topical tissue molecular imaging (with diffusion, imaging agent chemical/binding properties, tissue staining, rinsing, imaging, and data analysis protocols all being subject to alteration), thorough optimization margin analysis imaging protocols is untractable using experiments alone. Therefore, a salient feature of this dissertation was the development and validation of a “forward” mathematical diffusion and binding model for in silico testing of proposed paired-agent staining and rinsing protocols in thick tissue.
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Title: Integral, 1910
Date: 1910
Description: Volume 12 of Integral, the 1910 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by...
Show moreVolume 12 of Integral, the 1910 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by three different titles: Integral (1898-1910), Senior Class Book (1911-1912), and The Cycle (1913-1940). A 1902 volume of Integral is not a part of Galvin Library collections; it is uncertain of a yearbook was published that year. Publication of the Armour Institute ceased in 1941, when the Armour Institute of Technology merged with the Lewis Institute to form Illinois Institute of Technology.
Sponsorship: Scanning of the Armour Institute of Technology yearbooks was supported in part by an award from the Illinois State Historical Records Advisory Board, through funding from the National Historical Publications and Records Commission, National Archives and Records Administration.
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Collection: Armour Institute of Technology yearbooks, 1898-1940

Title: Hooker on Wells Street
Date: 1966-1969
Description: Date of photograph is unknown. Date range listed (1966-1969) is approximate. Title supplied by Howard LeVant.
Collection: Howard LeVant papers, 1950-2020

Title: Picasso statue
Date: 1970-1978
Description: Photograph of the sculpture Chicago Picasso and Daley Plaza, taken from a vantage point above the plaza. Date of photograph is unknown. Date...
Show morePhotograph of the sculpture Chicago Picasso and Daley Plaza, taken from a vantage point above the plaza. Date of photograph is unknown. Date range listed is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Nuns picnicking
Date: 1967-1969
Description: Photograph of nuns having a picnic on the banks of a body of water. Date of photograph is unknown. Date range listed is approximate. Title...
Show morePhotograph of nuns having a picnic on the banks of a body of water. Date of photograph is unknown. Date range listed is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Rabbi writing a new Torah
Date: 1977
Description: Title supplied by Howard LeVant, labeled as personal/historical photo.
Collection: Howard LeVant papers, 1950-2020

Title: Norwegian Landscape
Date: 1986
Description: Digitally modified photograph of a Norwegian landscape taken by photographer Howard LeVant as part of his Painting Technique series. Title...
Show moreDigitally modified photograph of a Norwegian landscape taken by photographer Howard LeVant as part of his Painting Technique series. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Bungalow - Alternate front elevations for wide or narrow lots
Date: 1990
Description: Hand-colored laser print.
Collection: Robert Philip Gordon papers, 1963-2010

Title: English Hill Street
Date: 1976
Description: Digitally modified photograph of an England street corner taken by photographer Howard LeVant as part of his Painting Technique series. Title...
Show moreDigitally modified photograph of an England street corner taken by photographer Howard LeVant as part of his Painting Technique series. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Northeast corner of 35th Street and State Street, Chicago, Illinois, January 24, 1954
Date: 1954-01-24
Description: Color slide depicting the intersection of 35th Street and South State Street, looking northeast. Photographer unknown, possibly a member of...
Show moreColor slide depicting the intersection of 35th Street and South State Street, looking northeast. Photographer unknown, possibly a member of the university's Department of Public Relations.
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Collection: Dan Ryan collection, 1954-1980

Title: Kaplan's Junkyard, Chicago, Illinois, 1959
Date: 1959
Description: Two photographs scanned from negatives, presumed to depict the demolition of Kaplan's Junkyard, once adjacent to the Illinois Institute of...
Show moreTwo photographs scanned from negatives, presumed to depict the demolition of Kaplan's Junkyard, once adjacent to the Illinois Institute of Technology Campus. The Chicago Land Clearance Commission acquired the land on which the junkyard stood in 1958, and demolition occurred in 1959, after which the land was sold to Illinois Tech. Photographer unknown.
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Collection: Office of Communications and Marketing photographs, 1905-1999

Title: Mecca Flats, Chicago, Illinois, ca. 1951
Date: 1951
Description: Photograph of the Mecca Flats, located at 3360 South State Street and constructed in 1891. The apartments were designed by Edbrooke & Burnham,...
Show morePhotograph of the Mecca Flats, located at 3360 South State Street and constructed in 1891. The apartments were designed by Edbrooke & Burnham, and were demolished in 1952. Originally constructed as a hotel for the World's Columbian Exposition of 1893, the 96-unit Mecca building became an apartment building after the fair. The building was acquired by Illinois Tech around 1941, and was demolished in 1952 to make way for the construction of S.R. Crown Hall. The building was also known as Mecca Apartments, and The Mecca.
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Collection: Office of Communications and Marketing photographs, 1905-1999

Title: László Moholy-Nagy with hand sculptures, ca. 1945
Date: 1945
Description: Photograph of László Moholy-Nagy with hand sculptures. Photographer unknown. Date of photograph unknown. Date listed is approximate, based on...
Show morePhotograph of László Moholy-Nagy with hand sculptures. Photographer unknown. Date of photograph unknown. Date listed is approximate, based on notation found adjacent to photograph.
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Collection: Institute of Design records, 1937-ca. 1962

Title: László Moholy-Nagy
Description: Photograph of László Moholy-Nagy in profile. Photographer unknown. Date of photograph is unknown.
Collection: Institute of Design records, 1937-ca. 1962

Title: Blue skyline ad
Date: 1969-1978
Description: "New Priorities|New Directions" Print advertisement created by photographer Howard LeVant/LeVant Photography (other contributors unknown) for...
Show more"New Priorities|New Directions" Print advertisement created by photographer Howard LeVant/LeVant Photography (other contributors unknown) for Amoco Chemicals Corporation, featuring fiberglass windmills created to look like Chicago buildings. Date of advertisement is unknown. Date range listed (1969-1968) is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Armour Engineer, Index 1-8, 1909-1916
Date: 1916
Description: General index for volumes 1-8 of the Armour Engineer, a serial publication for Armour Institute alumni with school, research, and engineering...
Show moreGeneral index for volumes 1-8 of the Armour Engineer, a serial publication for Armour Institute alumni with school, research, and engineering news. Index compiled by Ellyn C. Broomell, Assistant Librarian, Armour Institute of Technology.
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Collection: Armour Engineer alumni magazine, 1909-1935

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