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Investigating the Impact of Brazing on Heat Exchanger Process Fluid Contamination
No full textBrazing is a joining process where two materials (metals or ceramics) are joined with a lower melting point filler metal. Brazing provides very strong and precise joints without melting the materials being joined. Brazing is being considered as an alternative method to create heat-exchangers; however, it is not known if the filler metal will cause additional impurities in the process fluid. This research explores the contingencies of nickel brazing when brazed joints are exposed to high-temperature solutions (80⁰C) for extended times. Our methods involve; soaking brazed 316L stainless steel samples, un-brazed Stainless Steel, “316” and GTAW (gas tungsten arc welding) stainless steel in three separate solutions; WFI (water for injection), CIP-100 (clean in place, alkine) and CIP-200 (clean in place, acidic) for a range of time periods to metal concentration changes within the process solutions. Furthermore, the effect of the brazing process on the stainless steels being joined will be assessed through electrochemical testing to compare corrosion performance before and after the braze heating cycle. This research will help to determine whether brazing is acceptable for manufacturing heat exchangers for use in heated, ultra-high purity water
Upcycling of Wastewater Algae
No full textMany companies use microalgae to clean their wastewater as a greener alternative to traditional wastewater treatment, but the disposal of this algae is costly to the company. For example, Anheuser-Busch spends about 1 million dollars per year to dispose of their wastewater algae. This project proposes to divert this waste to extract and isolate valuable compounds from the algae to create upcycled products that would eliminate the costs of algae disposal. In this project so far, the drying of the algae was examined through a variety of methods like oven and freeze drying. To determine what compounds we can isolate from the algae, inorganic and organic extraction methods were investigated and compared. In addition, the energy and cost were analyzed to see which drying method would be optimal for adoption by industry. ICP-MS was utilized to visualize how these different treatment processes affect the algae and analyze the extractions performed. These analyses set the foundation for this project’s future in upcycling these valuable compounds from wastewater algae into biofuels, fertilizers, and clean water
Ultraviolet Raman Spectroscopy Characterization of (Ba,Sr)TiO\u3csub\u3e3\u3c/sub\u3e Thin Film Heterostrucrures
No full textFerroelectrics based on BaxSr1-xTiO3 are materials are studied for various device applications, such as non-volatile memories and microwave devices with high dielectric permittivity at GHz frequencies and high tunability. We applied variable-temperature ultraviolet Raman spectroscopy to study barium strontium titanate-based, (BaxSr1-xTiO3)nBaxSr1-xO Ruddlesden-Popper (R-P) thin films grown by molecular beam epitaxy on SrTiO3 substrates. Raman spectra demonstrated that R-P samples were ferroelectric at low temperatures, and the ferroelectric phase transition temperatures, Tc, were determined from the analysis of temperature dependence of Raman intensities of phonon modes. We have also characterized homoepitaxial SrTiO3 films grown in various conditions by low temperature ultraviolet Raman spectroscopy. Bulk SrTiO3 has a cubic perovskite structure with all phonon modes being symmetry forbidden in the 1st order Raman spectra. Therefore, the defect-induced activation of the Raman peaks can be used to characterize the structural quality of the films. Our Raman results combined with the data from other characterization techniques show that the films grown by adsorption-controlled epitaxy at very high substrate temperatures (1450–1475℃) have the best crystalline quality in terms of the lowest amount of defects, such as non-stoichiometry
Decoding Carbonate Concentrations and Substitutions in Tooth Enamel Across the Tree of Life Using Paired Infrared Spectroscopy and X-Ray Crystallography
No full textCalcium phosphate constitutes the crystalline component of tooth enamel. Carbonate ions (CO3) are present in these crystals which alters their physical and chemical properties. We do not know whether carbonate concentrations vary across different organisms, or whether this variation is systematic based on evolutionary lineage. Using Infrared spectroscopy and X-ray crystallography on powdered enamel samples of different modern animals (mammals, reptiles, fishes) across the tree of life, we find correlations among carbonate content, fluorine content, and shape of the crystal lattice. Fluorine rich enamel in marine fish has lower carbonate contents and shorter lattices, while hydroxyl (OH) rich enamel in mammals, reptiles, and freshwater fish, has higher carbonate contents and longer lattices. Paleontologists use the chemistry of tooth enamel carbonate to reconstruct past environments and climates. Understanding an organism\u27s original chemistry and crystal structure can inform the degree to which ancient tooth enamel has been altered during fossilization, and consequently potential biases to interpretations of past environments and climate. Paired Infrared and X-ray crystal structure data show that carbonate substitution in the crystal structure clusters across different regions of the evolutionary tree of life, and provides a chemical and structural baseline against which fossil enamel can be compared
Social Perceptions of Korean Aegyo Based on Culture
No full textWhile Aegyo has traditionally been associated with women and often interpreted in a sexist context, it is becoming increasingly acceptable for men as Korean society evolves. These days, we frequently see both male and female K-pop artists actively displaying Aegyo in pop culture. Unlike in the past, many young women today reject Aegyo, recognizing it as a submissive expression toward men. They also often dismiss Aegyo performed by Korean men, calling it cringy or not manly. I hypothesized that the growing popularity of Aegyo across genders in the Korean entertainment industry signified that it is becoming more widely accepted and celebrated as a part of Korean culture. I also surmised that people raised in Korea would generally be more accepting of Aegyo than people raised in Western countries. To explore these perspectives, I interviewed separate groups of college-aged Koreans, Korean-Americans, and foreigners (primarily Americans learning Korean), to gather their views on Aegyo in Korean culture. Koreans raised in Korea tend to be more neutral about most situations involving Aegyo, often avoiding giving a clear opinion on the matter. Yet, even with neutral or slightly negative views, nearly two-thirds of them still reported frequently performing Aegyo. Additionally, nearly 100% of participants stated that Aegyo and feminism are not related at all
Investigating the Effects of Adverse Childhood Experiences on Adult Friendship Making
No full textHumans are a highly social species and often spend much of their time and energy trying to make friends. But, each individual enters into this endeavor with different strengths and challenges. Here, we focus on understanding one specific source of challenges when making friends: adverse childhood experiences. Past research has indicated a number of benefits and costs inherent in making friends, including its impacts on mental and physical health, academic performance, and behavior. We expect the results of this study will further elucidate the social impact of adverse childhood experiences. Specifically, we expect people who have higher scores on the Adverse Childhood Experiences Questionnaire (ACES) will also score higher on avoidance measures and be less inclined to pursue new friendships. This study uses a questionnaire method presented to university students, where we asked questions regarding their childhood experiences, perceptions of friendships, and their willingness to make new friendships. The impact of these potential results will facilitate a deeper understanding of how early life experiences impact one’s desire to engage in friendships
Additively Manufactured Boron Nitride Coatings for Extreme Environments
No full textThe advancement of active materials, electronics, and sensors has increased the demand for nanoparticle-based printed electronics. An emerging microscale Additive Electronics Manufacturing (AEM) method to meet this demand is Aerosol Jet Printing (AJP). AJP offers high-resolution deposition for printed electronics using nanomaterial inks. Boron nitride (BN) is a nanomaterial of high interest due to its high thermal conductivity, electrical insulation, and corrosion resistance, making it well suited for extreme environments. This work focused on optimizing BN inks for AJP, which are then used to print dense, homogeneous, and cohesive BN films that insulate and protect electronic sensors in extreme environments. This requires a fundamental understanding of ink rheology and its evolution throughout the ink formulation and printing process. Particle size analysis (PSA) was used to monitor changes in particle size during ink formulation, which provided insight into dispersion stability and process optimization. Scanning electron microscopy (SEM) verified the results found in PSA and was used to optically image BN films. The findings showed a 98.87% consolidation of particle size in the ink formulation, however, dispersion instability was observed. Overall, this study developed BN films for extreme environments, analyzing ink behavior and AJP parameters
Lyme Disease in the Pacific Northwest
Get PDFTransmitted by ticks, Lyme disease is a zoonotic infectious disease that can cause debilitating long-term illness throughout the whole body that may affect many communities. This disease is caused by the bacterium Borrelia burgdorferi, carried by a biological vector known as the Ixodes tick. In the United States, Lyme disease has been primarily found in the Northeast via the Ixodes scapularis, commonly known as the “deer tick.” Along the West Coast of the United States, many people are unaware they and their pets are consistently exposed to this disease in their environment. The Ixodes pacificus has been found in all but two counties in California. Across the Pacific Northwest, the Ixodes pacificus tick, known as the “western black-legged tick,” carries the same bacterium as its distant relative. The current literature review will demonstrate the difference between the two vectors to promote education about recognizing a tick and Lyme disease in the Pacific Northwest. The public may be unaware of the dangers due to a lack of knowledge and education regarding the same. The ability to recognize a tick on a family member, yourself, or pet before it is too late could be the difference between maintaining good health and a painful long-term systemic disease
The Effects of Studying Literary History on American College Students
Get PDFThis study explores the effects that studying literary texts from diverse cultures around the world has on American college students. The goal of this study is to understand what benefits (and risks, if any) students experience when they become familiar with major texts from cultures that are different from their own. The students that chose to participate in this study are both past and present students from Literary History I and II courses at Boise State University. Data from past students was collected through an online survey including questions about their experiences studying texts from global literary history. This is an ongoing study, and data from present students is being retrieved from written class assignments and observations from in-class discussions. Based on our survey findings, responses about these effects have been overwhelmingly positive, highlighting the benefits of studying literature more generally, as well as valuing the importance of global literature. The discipline of literature gives students the unique opportunity to challenge their own perspectives, uncover their own values, and understand the reasons behind them. This highlights not only the significance of the humanities, but the enduring relevance and vitality of literature
Location Specific Characterization of Laser Powder Bed Fusion Inconel 718
No full textTo accelerate the deployment of advanced nuclear reactors, innovative manufacturing techniques are being developed to enable rapid prototyping and reduce qualification timelines. Nickel-based superalloys, such as Inconel 718, are critical for these applications due to their exceptional strength at high temperatures, as well as their high creep and corrosion resistance. Additive manufacturing (AM) offers advantages for producing these components, including complex geometry fabrication, accelerated fabrication times, and reduced material waste compared to subtractive methods. However, AM-produced parts can exhibit greater variability in micromechanical and chemical characteristics than traditionally manufactured parts. This study collected extensive data detailing the microstructure, microhardness attributes, and light element (oxygen and nitrogen) distribution across eighteen Inconel 718 parts produced via laser powder bed fusion with controlled build parameters. The relationship between spatial proximity, print parameters, and material properties demonstrated a variation with respect to build height, including a positive difference of 22% oxygen between the initial layers and the final layers. Less prominent trends with nitrogen content and microhardness were also present