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Full-Text Articles in Engineering
Sustainable Underground Reactive Barrier To Attenuate Contaminants From Agricultural Drainage, Yuchuan Fan
Sustainable Underground Reactive Barrier To Attenuate Contaminants From Agricultural Drainage, Yuchuan Fan
Doctoral Dissertations
Denitrifying bioreactor (DNBR) has become a popular edge-of-field practice applied to reduce nitrate over the Mississippi river and to prevent a downstream hypoxic zone occurring at the Gulf of Mexico. Despite widespread field and laboratory studies, fewer investigations have been directed toward a systematic means of evaluating the nitrate removal performance achieved by various filling materials, abiotic factors, and other critical parameters. Our ultimate goal is to improve the nitrate removal by choosing the optimum fill materials and operate under optimal conditions, meanwhile, modeling the DNBR by critical variables. This study begins by establishing a global database. Forty filling materials …
Investigation Of Control Parameters, Strategies, And Transport Modeling For Effective Electrokinetic Nanoparticle Treatment Of Cementitious Materials, Huayuan Zhong
Doctoral Dissertations
Various deleterious chemical species (including sulfates, chlorides, and others) contaminate concrete structures which are inherently porous and thus suffer from compromised durability. Several technologies have been developed for repairing concrete or enhancing the service life. Nevertheless, their efficiency, practicability, and cost can vary widely. Compared with chemical grout, fiber wrap, and traditional repair technology, electrokinetic nanoparticle treatment (EN) has been found to provide remarkable benefits for strength restoration and mitigation of durability problems via porosity reduction. Nanoparticle instability and over dosage issues can arise and lead to problems during treatments. In many cases, these treatment processes have been accompanied by …
Digital Cutting Force Modeling For Milling Operations, Timothy T. No
Digital Cutting Force Modeling For Milling Operations, Timothy T. No
Doctoral Dissertations
Process improvement in milling through improved understanding of machining dynamics is an on-going research endeavor. The objective of this project is to advance digital modeling of the milling process by incorporating tool-specific geometry in the machining analysis. Structured light scanning will be used to perform tool geometry measurements and produce a 3D model. The 3D model data will include the spatial location of the cutting edges, as well as the rake and relief profiles from the tool cross section. The rake and relief profiles will be imported, together with the work material flow stress model, into a finite element analysis …
Exposure Assessment Of Emerging Contaminants: Rapid Screening And Modeling Of Plant Uptake, Majid Bagheri
Exposure Assessment Of Emerging Contaminants: Rapid Screening And Modeling Of Plant Uptake, Majid Bagheri
Doctoral Dissertations
"With the advent of new chemicals and their increasing uses in every aspect of our life, considerable number of emerging contaminants are introduced to environment yearly. Emerging contaminants in forms of pharmaceuticals, detergents, biosolids, and reclaimed wastewater can cross plant roots and translocate to various parts of the plants. Long-term human exposure to emerging contaminants through food consumption is assumed to be a pathway of interest. Thus, uptake and translocation of emerging contaminants in plants are important for the assessment of health risks associated with human exposure to emerging contaminants. To have a better understanding over fate of emerging contaminants …
Cyclic Sequential Adsorption Desorption/Thermal-Catalytic Oxidation Of Volatile Organic Compounds: Material Development, Process Advancement/Improvement, And Numerical Modeling, Simulation And Optimization, Busuyi Ojo Adebayo
Doctoral Dissertations
"Volatile organic compounds (VOCs) are a group of useful organic chemicals but when emitted have contributed to air pollution. They affect human health, cause environmental degradation and contaminate our waters and soils, so they need to be controlled. When they exist in dilute concentrations, abatement becomes challenging, thus requiring advanced abatement methods, e.g., sequential adsorption desorption/thermal-catalytic oxidation process. The overall goal of this research was to abate dilute streams of VOCs via the process. The specific objectives were to 1) develop novel adsorbent/catalyst dual-function materials (DFMs) for the process, 2) improve the operability of a one-bed-one-column reactor configuration for the …