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- Title
- WASTEWATER COLLECTION SYSTEM MODELING: TOWARDS AN INTEGRATED URBAN WATER AND ENERGY NETWORK
- Creator
- Wang, Xiaolong
- Date
- 2020
- Description
-
Wastewater collection systems, among the oldest features of urban infrastructure, are typically dedicated to collect and transport wastewater...
Show moreWastewater collection systems, among the oldest features of urban infrastructure, are typically dedicated to collect and transport wastewater from users to water resource recovery facilities (WRRFs). Since the 1970s, wastewater engineers and scientists have come to understand that wastewater collection systems can bring benefits for urban water and energy networks, including thermal energy recovery and converting pipelines to bioreactors. However, there is little knowledge about the temporal and spatial changes of collection systems parameters that are important for these applications. Furthermore, the vast majority of existing studies of these applications have focused on laboratory or extremely small-scale systems; there have been few studies about beneficial applications associated with large-scale systems. The purpose of this study is to increase our understanding of how urban wastewater collection systems can bring potential benefits to urban water and energy systems. Models describing wastewater hydraulics, temperature, and water quality can provide valuable information to help evaluate thermal energy recovery and wastewater pretreatment feasibility. These kinds of models, and supporting data from a case study, were used in this study; sizes of the theoretical wastewater collection systems range from 2.6 L/s to 52 L/s, and the sample locations of the case study had flows ranging from 2.3 L/s to 24.5 L/s. A cost-benefit analysis of wastewater source heat pumps was used to evaluate the thermal energy recovery feasibility for different sizes of wastewater collection systems. Results show that the large collection system can support a large capacity heat pump system with a relatively low unit initial cost. Small collection systems have a slightly lower unit operating cost due to the relatively high wastewater temperature. When the heat pump system capacity design was based on the average available energy from the collection system, larger systems have lower payback times; the lowest payback time is about 3.5 years. The wastewater quality model was used to describe the dissolved oxygen (DO) and organic matter concentrations changes in the collection system. The model provides a framework for predicting pretreatment capability. Model results show that DO concentration is the limiting parameter for organic matter removal. Larger collection systems can provide more organic matter removal because they provide relatively longer retention times, and they offer the potential for greater DO reaeration. The model can also be used to identify environmental conditions in sewer pipelines, providing information for potential issues predication.
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- Title
- DEVELOPMENT OF FULLY BIOCOMPATIBLE HYDROGEL NANOPARTICLE FORMULATIONS FOR CONTROLLED-RELEASE DELIVERY OF A WIDE VARIETY OF BIOMOLECULES
- Creator
- Borges, Fernando Tancredo Pereira
- Date
- 2020
- Description
-
In recent years, our group has focused on the production of PEGDA-based hydrogel scaffolds and nanoparticles for drug delivery of small...
Show moreIn recent years, our group has focused on the production of PEGDA-based hydrogel scaffolds and nanoparticles for drug delivery of small molecules. However, with recent advances in modern therapeutic treatments, such as protein and genetic engineering, there is an increasing need for the development of drug delivery devices that would be able encapsulate larger molecules. Therefore, the goal of this thesis work was to develop a systematic way to produce fully biocompatible PEGDA-based hydrogel nanoparticle formulations that would be able to encapsulate any size molecule, ranging from small ionic molecules, to peptides and proteins, all the way to large nucleic acids, and deliver it in a controlled manner.The first of part of this work consisted of developing a stable and reproducible process for the production of hydrogel PPi-NPs. Initial studies were done in order to assess the influence of phosphate salts in the polymerization system and it was found that both monophosphate and polyphosphate salts significantly damper the NVP homo-polymerization kinetics, but do not affect the co-polymerization of NVP and PEGDA. Then, emulsion stability studies were done to determine whether phosphate salts affected the stability of the minimeulsion system used in the production of the nanoparticles. Cloud point measurements and droplet size screening measurements showed that by transitioning from a Pi-loaded emulsion system to a PPi-loaded emulsion system, the required HLB of the emulsion shifts by 1.5 points. Upon correction for that shift, a reproducible process for production of PPi-loaded nanoparticles was obtained. A parametric study was then performed to see how the different process parameters affected the different properties of the produced particles. The second part of the work consisted in developing a platform for encapsulation of large to very-large molecules within these hydrogel systems. A new set of equations was developed for better estimation of the interstitial space, available for encapsulation of molecules, of crosslinked polymers that used very high molecular weight crosslinkers and/or high amounts of crosslinker. Upon development of this new set of equations, hydrogel discs were made via photopolymerization in order to validate the equations. By introducing a third monomer, EGA, and varying the molecular weight and concentration of the crosslinker, hydrogels with a wide range of mesh dimensions from 25 to 700 were achieved. These gels were then used to encapsulate 4 different sample molecules of varying molecular weights and size. A new heuristic was developed for encapsulation of non-spherical molecules, where the aspect ratios of the molecule and of the polymer network are considered. By varying the size of the ratios of the dimensions of the hydrogel network to the dimensions of the molecule, significantly different release profiles of small molecules, peptides and oligonucleotides were obtained. Finally, in order to explore different administration routes, the process was transitioning into being fully biocompatible. The organic solvent previously used in the emulsion system was replaced by soybean oil and the surfactants were replaced by a food-grade surfactant, PGPR, to form Bio-Compatible Nanoparticle Emulsions (BCNEs). Qualitative release from the BCNEs was shown. A new method for quantitative measuring of release from BCNE was developed. Release from QK-BCNE was observed up to 46 days, which is unprecedented for sustained-release and revolutionary for the field. A BCNE spreadable ointment formulation was also developed.
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- Title
- IMAGE-ANALYSIS WITH FIJI PROGRAM ON PERIPHERAL BLOOD MONOCULAR CELLS AFTER CONSUMPTION OF HIGH-FAT, HIGH CARBOHYDRATE MEAL WITH OR WITHOUT ADDITION OF SPICES – A SINGLE-CENTER RANDOMIZED, BLINDED, PLACEBO-CONTROLLED, 4-ARM, 24HR ACUTE CROSSOVER STUDY
- Creator
- Tsai, Meng Fu
- Date
- 2020
- Description
-
Chronic low-grade inflammation plays a significant role in developing various chronic diseases, such as cardiovascular disease and type II...
Show moreChronic low-grade inflammation plays a significant role in developing various chronic diseases, such as cardiovascular disease and type II diabetes. Western-type diets characterized by high-fat (saturated fat) and high-carbohydrate (HFHC) calories induce oxidative stress leading to inflammation. Polyphenol rich foods, such as berries, tea, and herbs and spices, have antioxidant properties. Spices have been shown to have anti-inflammatory effects in cell and animal studies; however, data are limited in humans. In the present study, we hypothesized that bioactive polyphenolic compounds in herbs and species would reduce diet-induced inflammation in overweight and obese (OW/OB) individuals. In a randomized, single-blinded 4-arm, 24-h, crossover clinical trial, sixteen OW/OB adults consumed an HFHC meal with and without three herbs and spices combinations, including Italian herbs (rosemary, basil, thyme, oregano, and parsley), cinnamon and pumpkin pie spice (cinnamon, ginger, nutmeg, and allspice) on four separate occasions at least three days apart. Markers of inflammation were assessed before and at 2, 4, 5.5, and 7 hours after meal consumption by tracking nuclear translocation of nuclear factor kappa B (NF-κB), a transcription factor in inflammatory signaling, in human peripheral blood monocular cells (PBMCs) and by measuring plasma interleukin-6 (IL-6), a pro-inflammatory cytokine. Nuclear translocation of NF-κB and the proportion of PBMCs activated were estimated through a new method leveraging machine-learning immunofluorescence image analysis. Metabolic markers were also investigated by RX Daytona automated clinical chemistry analyzer. Statistical analysis was conducted using a statistical package for the social sciences (SPSS) (α<0.05, significance). Preliminary results suggested the pumpkin pie spice mixture may improve inflammatory status. Compared to the control meal, the meal with pumpkin spice reduced nuclear translocation of NF-κB and proportion of PBMCs activation, p=0.007, and p=0.005, respectively. The addition of herbs/spices in HFHC meal had no apparent effect on postprandial glucose, insulin, or IL-6 concentrations compared to the control meal. Increased triglyceride concentrations were suggested after consuming the meal with Italian herbs compared to control (p=0.004). Overall, the results of this research suggested the potential of pumpkin pie spice as having anti-inflammatory effects in the context of a typical western-style eating pattern. A major component of this research was to develop a new method for assessing real-time inflammation in the human body. While the method and data are encouraging, upgrading image resolution and programming will be the subject of future research.
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- Title
- Gender Stereotype Biases Within Law Enforcement Clinical Psychological Evaluation
- Creator
- Porter, Maxwell G.
- Date
- 2023
- Description
-
Female representation in law enforcement, despite significant improvements in past decades, remains markedly low at approximately 12%. One...
Show moreFemale representation in law enforcement, despite significant improvements in past decades, remains markedly low at approximately 12%. One possible barrier is the clinical psychological evaluation (CPE), a type of individualized assessment used to evaluate the mental or emotional fitness for duty of applicants. The present study examines the presence of potential gender bias in CPE for law enforcement positions by examining self-report personality assessment scores as well as narrative CPE recommendation reports generated by evaluating psychologists. Archival CPE data collected between 2014 through 2019 was obtained from a personnel selection consulting firm for entry-level law enforcement candidates (n = 390). Data included candidate scores on self-report psychological assessments (16PF, IPI-2), candidate background information, and psychologist-generated evaluation reports. A computer-aided text analysis using LIWC-22 was used to measure gender related inferences in the narrative report. Results indicated that (a) women received significantly lower assessor recommendation ratings than men, (b) significant differences in self-report personality scores were observed, however these were limited to a narrow subsection of traits, (c) gender was no longer a significant predictor of CPE outcome after controlling for applicant personality trait scores, and (d) meaningful differences in agency-related inferences in the narrative reports were observed, but it is unclear whether gender stereotypes influenced the reports. Practical implications, study limitations, and directions for future research are discussed.
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- Title
- In situ EXAFS studies of novel Palladium-based anode catalysts for direct ethanol and formic acid fuel cells
- Creator
- Su, Ning
- Date
- 2024
- Description
-
In this work we made nanoscale uniform deposition of Pd based anode catalyst on the transition metal Au (with atomic ratio Pd:Au=1:10) support...
Show moreIn this work we made nanoscale uniform deposition of Pd based anode catalyst on the transition metal Au (with atomic ratio Pd:Au=1:10) support of direct liquid ethanol fuel cells (DLEFCs) and direct liquid formic acid fuel cells (DLFAFCs). Synthesizing with uniform dispersion and catalyst nanoparticle dimensions understand the role of Pd reaction on its support in the direct EOR (ethanol oxidation reaction) and FOR (formic acid reaction) pathways, we performed in situ Pd K-edge X-ray absorption spectroscopy measurements as a function of potential using a custom-designed flow cell with the catalyst deposited on the glassy carbon window. We did in-situ EXAFS to better understand the reaction mechanism of Pd1@Au10 anode catalyst with EOR and AOR in nanoscale. Compared EOR with FOR electrochemical performance showed Pd@Au&C played better in ethanol than HCOOH and more stable which the the current density can reach up to 1216.25 mA·mg-1 Pd of EOR with Pd1@Au10&C in 1M KOH+1M EtOH (CH3CH2OH) on the ethanol fuel cells (DLEFCs), and 3.56 times higher of the EOR current compared with commercial Pd@C
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- Title
- Gwendolyn Brooks receiving an honorary degree at from Illinois Institute of Technology, Chicago, Illinois, 1968
- Date
- 1968
- Description
-
Photograph of Gwendolyn Brooks, then Chicago's Poet Laureate, receiving an honorary degree from Illinois Institute of Technology. Photographer...
Show morePhotograph of Gwendolyn Brooks, then Chicago's Poet Laureate, receiving an honorary degree from Illinois Institute of Technology. Photographer unknown.
Show less - Collection
- Office of Communications and Marketing photographs, 1905-1999
- Title
- Ekco Pool, Illinois Institute of Technology, Chicago, Illinois, ca. 1970s
- Date
- 1970-1979
- Description
-
Photograph of students in Ekco Pool on the lower level of Keating Hall. Date of photograph is unknown. Date range listed is approximate.
- Collection
- Office of Communications and Marketing photographs, 1905-1999
- Title
- Exhibition announcement for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, 1996, verso
- Date
- 1996
- Description
-
Exhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY,...
Show moreExhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, September 20-October 17, 1996. The exhibit commemorated the 60th anniversary of American Abstract Artists group, and included work from founding and current members, including Mary Henry's Verklaerte Nacht (acrylic on canvas, 1996). The recto of the card includes a detail of the frontispiece of the original 1937 American Abstract Artists portfolio.
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- Mary Dill Henry Papers, 1913-2021
- Title
- Exhibition announcement for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, 1996, recto
- Date
- 1996
- Description
-
Exhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY,...
Show moreExhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, September 20-October 17, 1996. The exhibit commemorated the 60th anniversary of American Abstract Artists group, and included work from founding and current members, including Mary Henry's Verklaerte Nacht (acrylic on canvas, 1996). The recto of the card includes a detail of the frontispiece of the original 1937 American Abstract Artists portfolio.
Show less - Collection
- Mary Dill Henry Papers, 1913-2021
- Title
- Exhibition announcement for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, 1996
- Date
- 1996
- Description
-
Exhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY,...
Show moreExhibition annoucement postcard for the exhibit Pioneers of Abstract art at the Sidney Mishkin Gallery, Baruch College, New York, NY, September 20-October 17, 1996. The exhibit commemorated the 60th anniversary of American Abstract Artists group, and included work from founding and current members, including Mary Henry's Verklaerte Nacht (acrylic on canvas, 1996). The recto of the card includes a detail of the frontispiece of the original 1937 American Abstract Artists portfolio.
Show less - Collection
- Mary Dill Henry Papers, 1913-2021
- Title
- Exhibition announcement for Mary Henry's show Selected Works at Whatcom Museum of History and Art, Bellingham, Washington, February 6-April 17, 1988
- Date
- 1988
- Description
-
Exhibition annoucement postcard for Mary Henry's show Selected Works at Whatcom Museum of History and Art, Bellingham, Washington, February 6...
Show moreExhibition annoucement postcard for Mary Henry's show Selected Works at Whatcom Museum of History and Art, Bellingham, Washington, February 6-April 17, 1988.
Show less - Collection
- Mary Dill Henry Papers, 1913-2021
- Title
- Benjamin de Brie Taylor painting the Hawk mural in Ekco Pool, Illinois Institute of Technology, Chicago, Illinois, ca. 1980
- Date
- 1980
- Description
-
Photograph of Benjamin de Brie Taylor and an unidentified student painting the mural above Ekco Pool in Arthur Keating Hall. The mural's hawk...
Show morePhotograph of Benjamin de Brie Taylor and an unidentified student painting the mural above Ekco Pool in Arthur Keating Hall. The mural's hawk was later adopted this as the official logo of the IIT Athletic Department. Taylor was Director of the Institute of Design at IIT from 1973 to 1975, and remained on the faculty at ID until 1987. Photographer unknown. Date of photograph is unknown. Date listed is approximate.
Show less - Collection
- Office of Communications and Marketing photographs, 1905-1999
- Title
- Two students in dormitory room, Illinois Institute of Technology, Chicago, Illinois, ca. 1960s
- Date
- 1960-1969
- Description
-
Photographer unknown. Date of photograph is unknown. Date range listed is approximate.
- Collection
- Office of Communications and Marketing photographs, 1905-1999
- Title
- Adaptive Learning Approach of a Domain-Aware CNN-Based Model Observer
- Creator
- Bogdanovic, Nebojsa
- Date
- 2023
- Description
-
Application of convolutional neural networks (CNNs) for performing defect detection tasks and their use as model observers (MO) has become...
Show moreApplication of convolutional neural networks (CNNs) for performing defect detection tasks and their use as model observers (MO) has become increasingly popular in the medical imaging field. Building upon this use of CNN MOs, we have trained the CNNs to discern between the data it was trained on, and the previously unseen images. We termed this ability domain awareness. To achieve domain awareness, we are simultaneously training a new variation of U-Net CNN to perform defect detection task, as well as to reconstruct a noisy input image. We have shown that the values of the reconstruction mean squared error can be used as a good indicator of how well the algorithm performs in the defect localization task, making a big step towards developing a domain aware CNN MO. Additionally, we have proposed an adaptive learning approach for training these algorithms, and compared them to the non-adaptive learning approach. The main results that we achieved were for the ideal observers, but we also extended these results to human observer data. We have compared different architectures of CNNs with different numbers and sizes of layers, as well as introduced data augmentation to further improve upon our results. Finally, our results show that the proposed adaptive learning approach with introduced data augmentation drastically improves upon the results of a non-adaptive approach in both human and ideal observer cases.
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- Title
- #MeToo: What Urged Users to Post?
- Creator
- Hirsh, Rachel Anna
- Date
- 2023
- Description
-
In this dissertation, I explore the motivations that compelled individuals to share their stories during the #MeToo movement, an unprecedented...
Show moreIn this dissertation, I explore the motivations that compelled individuals to share their stories during the #MeToo movement, an unprecedented digital phenomenon that thrust discussions of sexual harassment and assault into the public sphere. The central research question guiding this study was, "What urged users to post during the #MeToo movement?," which worked to uncover why and how the movement became so widespread.. Research demonstrates that when people are sexually harassed or assaulted, often times they do not come forward (Hlavka, 2014). Spencer et al. shares some of the common reasons women do not come forward are that they don’t classify their harassment or assault as a big enough deal, they do not know who or how to report it, they are afraid, they were drunk, they are ashamed, they don’t want to get their assailant in trouble, or they blame themselves (2017). However, those reasons fell by the wayside, as so many people came forward during the #MeToo movement. This paper aims to figure out why that was and how we can continuously get survivors to come forward. This paper also asks the question, did people come forward to share testimony, be part of a movement, or both?Two distinct hypotheses were formulated to unpack the complex dynamics at play The first hypothesis posited that users who engaged with central nodes, encompassing key figures within the #MeToo movement, original contributors, celebrities, and influencers, were more inclined to hold a positive outlook on the movement as a progressive step for women. This data was collected through a quantitative survey, and the analysis yielded inconclusive results, with 79.15% of the sample population expressing support for the movement while only 54.17% reported following central nodes. Qualitative interviews further underscored the multifaceted nature of motivations.The second hypothesis posited that individuals were more inclined to share their personal experiences of harassment or assault online when they observed weak ties within their social networks, such as acquaintances or friends of friends, sharing their own stories. The findings from survey data revealed that 68.87% of participants witnessed weak ties sharing personal experiences or using the #MeToo hashtag on their social media platforms. Qualitative interviews unanimously highlighted the significant influence of observing friends or weak ties posting about their experiences, further underscoring the diversity of motivators behind #MeToo participation.These findings shed light on the multifaceted nature of online activism and the pivotal role of personal networks in shaping the movement's trajectory. In essence, this research demonstrates that while the motivations for user participation in the #MeToo movement are diverse and complex, the presence of weak ties, or distant social relationships or relationships with infrequent interactions, within social networks emerges as a critical influence.
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- Title
- Improving Niobium Superconducting Radio-Frequency Cavities by Studying Tantalum
- Creator
- Helfrich, Halle
- Date
- 2023
- Description
-
Niobium superconducting radio-frequency (SRF) cavities are widely used accelerating structures. Improvements in both quality factor, Q0, and...
Show moreNiobium superconducting radio-frequency (SRF) cavities are widely used accelerating structures. Improvements in both quality factor, Q0, and maximum accelerating gradient, Eacc, have been made to SRF cavities by introducing new processing techniques. These breakthroughs include processes such as nitrogen doping(N-Doping) and infusion, electrochemical polishing (EP) and High Pressure Rinsing (HPR). [1] There is still abundant opportunity to improve the cavities or, rather, the material they’re primarily composed of: niobium. A focus here is the role the native oxide of Nb plays in SRF cavity performance. The values of interest in a given cavity are its quality factor Q0, maximum accelerating gradient Eacc and surface resistance Rs . This work characterizes Nb and Ta foils prepared under identical conditions using X-ray photoelectron spectroscopy (XPS) to compare surface oxides and better understand RF loss mechanisms in Nb SRF cavities and qubits. It is well established that Ta qubits experience much longer coherence times than Nb qubits, which is probably due to the larger RF losses in Nb oxide. By studying Tantalum, an element similar to Niobium, the mechanisms of the losses that originate in the oxide and suboxide layers present on the surface of Nb cavities might finally be unlocked. We find noticeable differences in the oxides of Nb and Ta formed by air exposure of clean foils. In particular, Ta does not display the TaO2 suboxide in XPS, while Nb commonly shows NbO2. This suggests that suboxides are an additional contributor of RF losses. We also suggest that thin Ta film coatings of Nb SRF cavities may be a way of increasing Q0. It is in the interest of the accelerator community to fully understand the surface impurities present in Nb SRF cavities so that strategies for mitigating the effects can be proposed.
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- Title
- Evaluation of the efficacy of power ultrasound technology coupled with organic acids to reduce listeria monocytogenes on peaches and apples
- Creator
- Joshi, Mayura Anand
- Date
- 2024
- Description
-
Fresh fruits and vegetables are prone to microbial contamination throughout different phases of human handling, processing, transportation,...
Show moreFresh fruits and vegetables are prone to microbial contamination throughout different phases of human handling, processing, transportation, and distribution. Emerging technologies, such as power ultrasound, have received attention due to their capacity to reduce or eliminate foodborne bacterial pathogens on these commodities. Power ultrasound, when combined with certain antimicrobials, has demonstrated its effectiveness as a valuable tool for washing fresh produce. The objective of this study was to examine the effectiveness of power ultrasound combined with organic acids on the reduction of Listeria monocytogenes on fruits. In this study, peaches and apples were subjected to surface inoculation with a four-strain cocktail of L. monocytogenes and dried for 1 h. Stomacher bags, containing 225 mL of citric, lactic, or malic acids at concentrations of 1%, 2%, or 5%, were employed for treating inoculated peaches and apples. The acid treatment was used alone, or in combination with power ultrasound for 2, 5, or 10 min. Water was used for controls. Before treatment, the initial population of L. monocytogenes on apples was lower compared to the initial population on peaches, with apples showing a 1.94 log CFU/fruit reduction. Water controls demonstrated no significant log reduction in both apples and peaches. The greatest L. monocytogenes reduction on apples occurred when treated with 1% citric acid for 2 min with power ultrasound where L. monocytogenes was significantly reduced from 6.98±0.88 log CFU/fruit to 5.56±0.91 log CFU/fruit. The greatest L. monocytogenes reduction on peaches occurred when treated with 5% citric acid for 5 min with power ultrasound where L. monocytogenes was significantly reduced from 7.44±0.45 log CFU/fruit to 6.68±0.40 log CFU/fruit. Overall, the combined effect of acid and power ultrasound was more pronounced in apples than in peaches. The survival of L. monocytogenes on apples and peaches appeared to be highly dependent on the specific treatment and hurdle technology applied. The combination of ultrasound hurdle technology with acid washing has proven effective in reducing L. monocytogenes on both peaches and apples, with a more significant impact observed on apples. While acid washing is a more economical option compared to ultrasound technology, the efficiency of microorganism reduction is considerably enhanced when power ultrasound is combined with organic acids. Looking ahead, the development of cost-effective power ultrasound methods could facilitate widespread adoption of ultrasound hurdle technology in the produce industry.
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- Title
- Characterization of Novel Concrete Formulations: High-Volume Fly Ash for Precast Industry Use and Non-Proprietary UHPC
- Creator
- Ordillas, Kurt Andrew
- Date
- 2024
- Description
-
The use of high-volume fly ash concretes can be challenging for high-early strength applications, such as in precast construction, largely due...
Show moreThe use of high-volume fly ash concretes can be challenging for high-early strength applications, such as in precast construction, largely due to potential delays in strength gain resulting from relatively lower heats of hydration of the underlying binder formulations. Considering that the use of higher levels of available fresh or landfilled fly ash as a replacement for traditional ordinary Portland cement (OPC) could result in more sustainable mix designs, a framework to develop novel, high-volume fly ash mixes with optimized dosages of commercial grade gypsum and accelerating admixtures to enhance early-age strength performance. Early-age mechanical properties such as compressive strength, modulus of rupture, and modulus of elasticity were evaluated starting within 24 hours of specimen preparation. Experimental test results were then characterized and subsequently analyzed relative to current design provisions to highlight the best performing trial mixes (with respect to the early-age strength target) and cases where current design provisions are either unconservative or overly-conservative with respect to the test data. Additionally, thermal properties of concrete produced with fly ash were tested with two different curing environments, along with using code equations to determine if high volume fly ash provides a higher thermal resistance compared to OPC concrete. Wrapping up cementitious replacement with non-proprietary ultra high-performance concrete (UHPC) for transportation structures. Then reproducing mixtures to ensure target compressive strength values could be reached. Followed by increasing batch size to a larger quantity using a large mixer to create full-size specimens.
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- Title
- Ink drawing, 1975
- Date
- 1975-07-07
- Description
-
Untitled drawing by Mary Henry, accompanied by mathematical calculations.
- Collection
- Mary Dill Henry Papers, 1913-2021
- Title
- Pencil Drawing on Tissue, undated
- Description
-
Untitled pencil drawing on tissue paper by Mary Henry, date unknown.
- Collection
- Mary Dill Henry Papers, 1913-2021
