Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Soil Moisture Dependent Runoff In A Dryland Region: An Investigation Of The Role Of Antecedent Conditions, Monitoring, And Modeling Strategies, Gerhard Schoener
Soil Moisture Dependent Runoff In A Dryland Region: An Investigation Of The Role Of Antecedent Conditions, Monitoring, And Modeling Strategies, Gerhard Schoener
Civil Engineering ETDs
Approximately 30% of the Earth’s land surface is characterized as arid or semiarid, including much of the western United States. Accurate runoff predictions are important for informed watershed management, particularly in rapidly urbanizing areas. Infiltration excess overland flow is the dominant mechanism for runoff generation in many dryland basins, and event-based infiltration or loss models are commonly used to estimate runoff. However, predictions are associated with considerable uncertainty due to the role antecedent soil moisture, an initial condition that must be set by the modeler. The objectives of my research were to (1) evaluate the impact of antecedent soil moisture …
Organic/Inorganic Interfacial Interactions Affecting Metal Reactivity: Water Treatment And Sensor Applications, Mohamed Nabil Shaikh
Organic/Inorganic Interfacial Interactions Affecting Metal Reactivity: Water Treatment And Sensor Applications, Mohamed Nabil Shaikh
Civil Engineering ETDs
The aim of this dissertation was to investigate the interactions occurring at the organic – inorganic interface between solid media and aqueous contaminants for water treatment and sensor applications. The gaps in current literature on these interfacial organic-inorganic interactions must be bridged in order to develop advanced water treatment and monitoring technologies for improving water quality and thus, restore and protect the contaminated water resources. As a part of this dissertation, manganese oxides-based composites and electrospun polymer mats were developed and investigated for gaining mechanistic insights of organic (bisphenol A and acetaminophen) and inorganic (uranium) contaminants removal, respectively. These reactions …
Hydrogeochemical Investigation Of Recharge Pathways To Intermediate And Regional Groundwater In Cañon De Valle And Technical Area 16, Los Alamos National Laboratory, Brendan W. Brady
Civil Engineering ETDs
In aquifers consisting of fractured or porous igneous rocks, as well as conglomerate and sandstone products of volcanic formations, silicate minerals actively dissolve and precipitate (Eby, 2004; Eriksson, 1985; Drever, 1982). Dissolution of hydrated volcanic glass is also known to influence the character of groundwater to which it is exposed (White et al., 1980). Hydrochemical evolution, within saturated zones of volcanic formations, is modeled here as a means to resolve the sources feeding a perched groundwater zone. By observation of solute mass balances in groundwater, together with rock chemistry, this study characterizes the chemical weathering processes active along recharge pathways …
Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca
Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca
Civil Engineering ETDs
Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …