TTU Published Journals @ Volpe Library
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*WINNER* Geochemical Fingerprinting of Natural Waters in Tennessee
No full textGeochemical fingerprinting is an analysis of the chemical species, present within natural waters, to determine both the source and alteration of these systems. These chemical fingerprints are defined as specific patterns of chemical species unique to each body of water. This research examines the presence of chemical species in surface waters that are located on two distinct physiographic regions of Tennessee: the Highland Rim and the Cumberland Plateau. Water bodies from these regions were chosen due to differences in local geology and land use patterns that each respective system are subjected to. Grab samples were obtained from various locations in order to obtain a true identity of each respective system. Multi variate analysis of variance (MANOVA) was then utilized to determine ratios of chemical species so that a comparative analysis could then be performed. These ratios of chemical species should indicate how local geology and land use patterns affect the chemical identity of natural waters within Middle Tennessee
The Reuse of Raw Materials - What is Most Beneficial in Reducing Construction Waste?
No full textConstruction and demolition waste is defined as relatively clean, heterogenous building material debris that come from construction, renovation, and demolition of bridges, roads, and buildings. It is thought that the construction industry uses 50% of all global energy and accounts for 35% of carbon dioxide emissions (Silvia et al., 2020). It is clear that to make an environmental impact, construction waste has to be attended to. The mainstream fix for this is recycling, but how truly effective is recycling? Recycling has processing costs that can virtually diminish its benefits. The idea of reuse eliminates conversion costs and decreases the demand for virgin resources. This research aims to determine the most sustainable way to reduce construction waste - reuse or recycling
Tensile and Fatigue Analysis of Functionally Graded Materials produced by Fused Filament Fabrication
No full textThe aim of this research study is the design, fabrication, and mechanical characterization of functionally graded composite materials using the fused filament fabrication (FFF) process. Chopped carbon fibre reinforced Polyethylene Terephthalate Glycol (CCF-PETG) and CCF-Nylon materials are fabricated by the Zmorph Fab desktop machine. The digital design of gradient structures is achieved by the voxelization process of the computer aided design (CAD) files. One of the main drawbacks of FFF parts is weak in shear strength that is due to the orientation of the raster plane, so FGM is one of the ways to enhance the mechanical properties of the material. Tensile behaviour of FGM parts fabricated in various processing parameters such as print directions, infill orientations, layer heights, etc. Tensile fatigue tests with a stress ratio of 0.1 were performed on each specimen at 90, 80, 70, and 60% of UTS. This knowledge-based study will be conducted with the hypothesis that the tensile strength of CF PETG and CF Nylon materials are less than that of functionally graded CF PETG and CF Nylon materials. The specimen's longest fatigue life was found at a stress level of 60%. This study presents a first-of-its-kind experimental examination of FGM tensile and fatigue characteristics
Dynamic Behavior Patterns of Particle Size Distribution of Dissolved Organic Carbon
No full textHumic acid (HA) is nonliving natural organic matter (NNOM) and exhibits dynamic behavior under certain shear conditions. This dynamic behavior presents a problem in water treatment as HA is a foulant and tends to disaggregate in turbulence and aggregate in the absence. The relationship between the aggregation time of NNOM found in pond water as a function of shear rate was investigated under constant 0.4 M CaCl2 concentrations. A rheometer (TA Instruments, Discovery HR 10) with a cup and bob attachment (TA Instruments, Peltier Concentric Cylinder) was utilized to induce shearing of NNOM in the range of 10 to 400 sec-1. Dynamic light scattering (DLS) was used to determine particle size distribution (PSD) patterns as the sample was allowed to relax over 120 minutes. The dynamic behavior of particles at ranges of 68.1-78.8nm, 396-459nm, and 4.8-5.56µm was explored. Additional data analysis suggests that there may be relationships between the increase or decrease of specific particles intensity or volume percentage, which were exposed to very specific shear rates
Financial and Banking Sector Cyber Risks
No full textFinancial Institutions are the leaders in global cyber defense as the banking sector is very attuned to cyber risks. This project aims to identify what is currently being employed by financial institutions to defend their assets. As well as identify recent attacks, including attacks on financial institutions and crypto investors. Most methods are malware, spyware, novel ransomware, and email phishing tactics. Some people are also learning to abuse QR codes on cryptocurrency ATMs to trick people into sending them crypto. Also, given recent events, these attacks are only increasing. Vulnerabilities are exploited every day in the banking/online banking sector; these attacks range from stealing passwords to complete money theft. These attacks can cause damages anywhere from 1 million - 200 million dollars. The primary victims in these attacks are usually higher-profile customers due to their immense asset holdings. One of the significant ways hackers can access users' banking information is by abusing phishing attacks. This often happens from unnatural links on social media or email posing as the users preferred online payment software such as PayPal. A great way of preventing these types of attacks is to be more vigilant and aware of the layout within the web pages and emails. They often contain the business name misspelled in the URL so that the user believes it is accurate
COVID-19 Occurance Prediction
No full textUnfortunately, Covid-19 has become the new normal of human existence. As a result of the pandemic lives have been lost and health of millions has been impacted. Trying to predict the prevalence of the virus in and around the regions where it is prevalent will help people in those areas or neighborhoods be cautious. This could also help the governments of each country, to be more aware of the virus widespread areas, and in turn protect lives of people. In this paper, we will be predicting the occurrence of Covid-19 by using geo spatial data, as well as data containing affected cases counts, death cases counts, and recovery cases counts of every country. Through data mining techniques, the data is preprocessed for errors or missing data and then classification and clustering analysis are used for prediction of the disease. Our hope is that these results will aide health workers in predicting the future case rate of covid-19, and the intensity of the disease in each country
Student Response to Supermarket Micro-column Chromatography Experiment
No full textChromatography is an important laboratory skill utilized throughout the chemical disciplines. Often, the materials required can be prohibitively expensive or overly hazardous. In the present study, we present an optimized procedure for an introductory chemistry laboratory experiment which uses only reagents and solvents purchased from a supermarket, which had previously been described in the literature. The impact of the experiment on student understanding of chromatography and whether using common materials to perform an experiment improved their interest in chemistry will be discussed
Assessing phylogenetic placement of an undocumented red-burrowing crayfish in the Tennessee River
No full textCrayfishes are a diverse freshwater group of crustaceans with over 450 species found in North America. This diversity is likely an underrepresentation given that many species are continually being described and several species represent species complexes. A particularly underrepresented group of crayfishes are within the burrowing species. Their burrowing behavior complicates sample collecting and many studies and surveys inaccurately portray community diversity. As a result, there are many undescribed taxa within burrowing crayfish. Investigators at the Tennessee Valley Authority discovered a previously undocumented red-burrowing crayfish within the middle Tennessee River watershed in Moore County, Tennessee. To assess the evolutionary and systematic placement of this novel taxa, we sequenced the mitochondrial COI and 16s genes and compared them to the Genbank and tissue sequences of morphologically similar species and subspecies. Our phylogenetic tree analyses identified members of the Cambarus striatus species complex from nearby areas as a sister clade to the red burrower and indicated strong support for the novel red burrower to represent a distinct evolutionary lineage. Future analyses of nuclear single nucleotide polymorphisms (SNPs) will provide a better depiction of where the novel red burrower lies in its respective phylogeny as well as delineate the genetic boundary between the red burrower and members of the Cambarus striatus species complex
*WINNER* Anatomical diversity of evolutionarily convergent egg mimics in passion flowers (Passiflora L.)
No full textPassiflora (passion flowers) is a large genus well known for its morphological diversity and close associations with butterflies. Many Passiflora possess structures that mimic butterfly eggs, discouraging gravid butterflies from laying eggs, thus reducing the number of caterpillars that would feed on the plant. These structures are varied in form and position and have evolved independently many times. This study will document and compare the structural homology of egg mimic structures in the genus. Multiple examples of egg mimics were paraffin embedded and sectioned with a microtome and stained to differentiate among the types of egg mimics. Preliminary results suggest that at least four classes of egg mimics exist: those derived from aborted flower buds, the leaf apex, the stipule apex, and from abaxial nectaries. These structures are not homologous but instead represent convergence in creating a visual display that confers a significant advantage in decreasing herbivory
Warrior mentality and the related impact on Law Enforcement Officers' perceptions of mental health through the lens of critical race theory
No full textThe purpose of this presentation is to highlight the concept of warrior mentality in law enforcement culture and the related implications on Law Enforcement Officers' (LEO's) mental health. Drawing upon critical race theory and a methodological review of the literature, the objectives will be to 1) define warrior mentality in the law enforcement setting, 2) describe warrior mentality and its relationship in critical race theory, 3) distinguish best practices for providing mental health services to this population, 4) discuss alternative treatment methods that could serve this population more effectively, and 5) promote an understanding of warrior mentality with an emphasis towards advocacy for LEO's mental well-being. Limitations and areas for future research will also be presented