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M (Mn/Fe/Co/Ni)-N-C Catalysts for Versatile Electrochemical Applications
No full textThe development of atomically dispersed M-N-C catalysts, where a metal (M) is supported on nitrogen-doped carbon (NC) matrix, is highly desirable for multifunctional electrocatalysis but remains a significant challenge due to size constraints and stability issues. In this study, we synthesized M-N-C catalysts (M = Fe, Co, Mn, and Ni) were synthesized using a Zn-assisted high-temperature treatment and characterized through various techniques. The electrocatalytic activity of the synthesized catalyst was evaluated for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline media. The findings revealed that Mn-N-C exhibited superior ORR (E1/2 = 0.90 V) and OER (n10 = 283 mV/cm2) performance compared to other catalysts. In contrast, Fe-N-C demonstrated the best HER activity (n10 = 65 mV/cm2). Theoretical studies indicated that the Mn-N-C catalyst\u27s HOMO energy was close to the LUMO of 02, enabling efficient electron transfer from Mn\u27s 3d orbitals to 02\u27s Tt* orbitals, weakening the O-O bond. Meanwhile, Fe-N-C exhibited optimal binding energy for 02 and H2, enhancing its OER and HER performance. This study presents a novel strategy for tuning the electronic and electrochemical properties of M-N-C catalysts, offering valuable insights for catalyst design in energy conversion applications
Development of environmentally friendly high-performance composite materials from soybean oil for electrical applications
No full textThe high-and low-voltage insulators, transformers, and power transmission cables of the electrical and electrotechnical sectors require durable insulating materials. Yet traditional petroleum-based insulators present environmental concerns and hence a need for sustainable alternatives. Our purpose is to use soybean oil-based polyurethane composites as eco-friendly insulation materials. Soybean-based polyurethanes were highlighted as a cost-effective yet highly performing solution for electrical insulation, standing to gain additional benefits in sustainability and innovation of renewable materials in industrial applications. Composites were prepared through silica (SiO2) filler and cured with isocyanates. We are in the process of testing dielectric strength, resistance, capacitance, and loss factor as a function of temperature, voltage, and frequency. The results will be discussed
Effect of Fillers and Flame Retardants on Thermal Stability and Fire Performance of Non-Edible Castor- Oil based Polyurethane Composite
No full textComposite materials are widely used in healthcare, automotive, aerospace, and construction due to their high mechanical strength. While petroleum-based epoxy resins are commonly used, researchers are increasingly turning to renewable resources for composite material development. Therefore, vegetable oils (VOs) are the promising alternative for epoxies and polyols derived from petroleum. VOs have an unsaturated double bond that is amenable to chemical modification. This study synthesized bio polyol using castor oil, a non-edible vegetable oil. A ring-opening reaction was used to modify castor oil, producing castor oil polyol (COP). Using FT-IR and GPC, the synthesized COP was described. Three distinct flame retardants (FRs), COP, and TiO2 as an inorganic filler were used to create composite materials. Melamine phosphate (MP), melamine (MA), and melamine phytate (MPHT) were employed as FRs. Here, bio-based phytic acid was used to create melamine phytate. Compared to all synthetic composite materials, MPHT 3wt% had a greater compression strength of 52 MPa. Additionally, the hardness and tensile strength were 70 and 22 MPa, respectively. Crucially, out of all the manufactured materials, the MPHT 5wt% sample showed the least amount of weight loss, just 2%. Although these composite materials are thermally robust, they degrade significantly at temperatures close to 400 C. Additionally, the composite materials\u27 chemical compatibility in toluene and water was assessed. With advantages including renewable sourcing, less environmental effect, and good mechanical strength, these bio-based composite materials provide a sustainable substitute for conventional petroleum-based products
Epoxidized Castor Oil-Based Thermosets with Reprocessable and Non-Reprocessable Properties
No full textCastor oil-based polymers have gained significant attention due to their renewable nature, low cost, and ease of processing, making them ideal for various applications, including biofuels and the petrochemical industry. Among these, epoxidized castor oil (ECO)-based thermosets have been extensively studied for their promising mechanical and thermal properties. This study focuses on recent advancements in ECO thermosets synthesized with 4,4- dithiodianiline (DTDA) which has aromatic disulfide bonds and 4,4-ditaminodiphenylmethane (DMPM) which has methylene bridge. FTIR spectroscopy confirmed the successful incorporation of epoxy functionalities into castor oil. The structure-reactivity relationship was examined through differential scanning calorimetry (DSC), which reveals that ECO_DMPM based thermosets exhibit higher glass transition (Tg) range compared to ECO_DTDA due to methylene group. The thermomechanical performance of the cured thermosets was investigated using dynamic mechanical analysis (DMA) shows that ECO-DMPM thermosets have the highest storage modulus, indicating superior mechanical strength and stiffness, compared to DTDA thermosets. Thermogravimetric analysis (TGA). Indicates good thermal stability across all thermosets, with degradation onset temperatures above 350 oC, though the presence of sulfur bonds may slightly reduce thermal stability. Tensile testing and GEL fraction measurements revealed strong correlations between monomer reactivity and final material properties. Moreover, the study highlighted the non-reprocessable nature of the ECO_DMPM thermosets. distinguishing them from other sustainable polymer systems. Their highly crosslinked structures limit recyclability but enhance their thermal and mechanical stability. The dynamic disulfide bonds in ECO_DTDA enable reprocessability, allowing the thermosets to be reshaped without significant performance loss
The World War\u27s Effects on Black Athletics
No full textThis article examines the effects that World War I and World War II had on black athletics, specifically the Negro Baseball League. The objective of this paper is to determine if the World Wars had a hand in the decline and subsequent shutting down of the Negro Baseball League. The forming of the Negro Baseball League and its status as a league is set perfectly in between both World Wars, with it forming in 1920 and declining towards the end shortly after World War II. Due to World War I, plans for a league were out on hold and would eventually be created in 1920. The much greater impact is World War II. The war surprising would result in an attendance boom for the Negro Baseball League. Due to Americans having more disposable income due to the war effort, the league was able to grow in popularity. A big factor that could have played a role in the integration of baseball came in 1941, when Franklin D Roosevelt established the Fair Employment Practices Committee. They would push for the inclusion of black players in baseball. Ultimately, this study shows that World War II would have monumental impacts on black culture as a whole. The war would help push for integration in baseball, which would be a catalyst for future integration. This integration would see the decline and shut down of the Negro Baseball League. This would help out black culture and athletics, but the findings in this article suggest that while it helped the overall impact of black integration and culture, baseball went from being a significant part of black business, to having little impact
Normal School Growth: The Case of Pittsburg\u27s State Manual Training Normal Under the Leadership of William A. Brandenburg
No full textThe Industrial Revolution during the late nineteenth and early twentieth centuries created an incentive to educate American youth. Prior to industrialism, schooling was limited in rural areas as children spent their days contributing to the family income. As demand for education rose, the demand for teachers simultaneously rose. In response, normal schools began to appear throughout the country. Pittsburg\u27s Auxiliary Manual Training Normal School, founded in 1903, was one of several products of the nation\u27s drive for education. Like several others, Pittsburg\u27s Normal was closely intertwined with industrialism. Many normal schools strove to teach industrial education in addition to regular public-school education to encourage students to pursue an industrial career. Opinions about normal schools are ever-changing - some historians praise them for equipping several generations with the skills they needed to sustain America\u27s industrial reputation, while other historians criticize them for prematurely arranging children\u27s careers and lessening the desire or need to go to college. Regardless of their debated moral intentions, most normal schools were widely successful - some more than others. This paper examines the factors that contributed to both normal school success and failure throughout America in comparison with Pittsburg\u27s Normal to determine if Pittsburg\u27s situation differed from others. By examining factors such as enrollment, community, location, and especially leadership, this paper argues that Pittsburg\u27s Normal did in fact encounter outstanding growth and development. Evidence finds that the school\u27s first official president, Dr. William A. Brandenburg, was probable causation for being the catalyst of growth for Pittsburg\u27s Norma
Distrust: The American Government and her Military
No full textThe goal of this research paper is to show how the lack of an American standing army led to a lack of efficiency in waging war. In the paper it looks at different ways this is caused throughout many different avenues. This includes matters such as a lack of a fighting force at the beginning of the conflict, a deficiency in military technology and training, as well as lack of a set-in place supply chain to feed and arm these campaigns. There will be different time periods discussed, and conflicts covered such as the War of 1812, Mexican American War, Civil War, and the Spanish American War. These wars have incidence where it can be viewed that the lack of a standing military caused the efficiency of the United States Military. This paper\u27s evidence is primary quotes from historical figures such as the founding fathers and generals who witnessed this firsthand. As well as the research and postings of fellow historians who have looked into this topic. This information will back up and proven with the usage of maps and charts to show the conflicts and the issues with the efficiency of the American way of waging war. In the end this paper aims to explain how the lack of a standing military led to the American fighting forces to be at a disadvantage at the beginning of conflicts in its fledgling years. Which in turn led to failures in these campaigns and loss of life
Improving Information Accessibility: A Student-Led Usability Study at PSU
No full textA moderated usability study was conducted to identify and address potential usability problems on the Pittsburg State University Graphic Communications website. Participants were guided through a series of tasks designed to explore key elements, such as enrolling in a major, viewing program areas and student work, finding faculty information, and locating financial assistance. Throughout the testing sessions, participants were encouraged to think out loud, allowing the researcher to capture immediate reactions, pain points, and navigation choices. The findings revealed insights into user expectations, the clarity of the site\u27s primary functions, and potential barriers in the enrollment process. Common areas of confusion included discovering emphasis area details and scholarship information, as well as locating tuition costs and frequently asked questions about admission. Additionally, the testing highlighted the importance of well-structured navigation menus and clearly labeled links. Recommendations derived from the study focus on simplifying the user path to key information, enhancing the layout of content, and ensuring a consistent visual hierarchy. These insights aim to improve overall user experience, ensuring that prospective students, faculty, and community members can efficiently locate and engage with relevant content
Bridging Emotional Bonds in Friendships: A Qualitative Study on Face-to-Face Vs. Mediated Communication at Pittsburg State University
No full textThe growing digital communication technologies have enabled people to get together in person as well as digitally. It has become nearly impossible for people to abandon digital communication technologies, as they provide an alternative to traditional face-to-face interactions for staying connected. Text messaging, social media apps, instant messaging, and video calls are different mediated forms of communication people use. The study explores face-to-face and other mediated communication in the context of friendships to observe and analyze the differences in convenience, emotional bonding, satisfaction, the usage of non-verbal cues, and the ambiguity element of communication. The researcher incorporated a qualitative research design involving in-depth interviews with five participants at Pittsburg State University, including three staff and two students. The participants were asked open-ended questions regarding the preference for communication in friendship, emotional connection and satisfaction, the non-verbal cues to understand each other, and how ambiguity in communication may be perceived when interacting face-to-face versus mediated channels. Moreover, the study investigates the amount of awareness of non-verbal cues, like body language and facial expressions, besides the way these are conveyed as opposed to face-to-face communication. The findings of this study are expected to reveal how communication channels influence emotional bonding in friendships, the amount of satisfaction participants feel in their interactions, and the impact of non-verbal cues and ambiguity in communication. By comparing face-to-face and mediated communication, the research will contribute to a better understanding of how modern communication technologies shape interpersonal relationships and how individuals pursue the complexities of digital and face-to-face interactions. This research acknowledges the challenges individuals face in communication in the digital era and the study of interpersonal relationships in an increasingly mediated world
Facile synthesis of loaf-like ZnMn2O4 nanorods and their excellent performance in Li-ion batteries
No full textBinary transition metal oxides have been attracting extensive attention as promising anode materials for lithium-ion batteries, due to their high theoretical specific capacity, superior rate performance and good cycling stability. Here, loaf-like ZnMn2O4 nanorods with diameters of 80-150 nm and lengths of several micrometers are successfully synthesized by annealing MnOOH nanorods and Zn(OH)2 powders at 700 oC for 2 h. The electrochemical properties of the loaf-like ZnMn204 nanorods as an anode material are investigated in terms of their reversible capacity and cycling performance for lithium-ion batteries. The loaf-like ZnMn2O4 nanorods exhibit a reversible capacity of 517 mAh/g at a current density of 500 mA/g after 100 cycles. The reversible capacity of the nanorods still could be kept at 457 mAh/ g even at 1000 mA/g. The improved electrochemical performance can be ascribed to the one-dimensional shape and the porous structure of the loaf-like ZnMn2O4 nanorods, which offers the electrode convenient electron transport pathways and sufficient void spaces to tolerate the volume change during the Li+ intercalation. These results suggest the promising potential of the loaf-like ZnMn2O4 nanorods in lithium-ion batteries