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Full-Text Articles in Engineering
Dehalococcoides Abundance And Alternate Electron Acceptor Effects On Large, Flow-Through Trichloroethene Dechlorinating Columns, Babur S. Mirza, Darwin L. Sorensen, Ryan Dupont, Joan E. Mclean
Dehalococcoides Abundance And Alternate Electron Acceptor Effects On Large, Flow-Through Trichloroethene Dechlorinating Columns, Babur S. Mirza, Darwin L. Sorensen, Ryan Dupont, Joan E. Mclean
Civil and Environmental Engineering Faculty Publications
Trichloroethene (TCE) in groundwater is a major health concern and biostimulation/bioaugmentation-based strategies have been evaluated to achieve complete reductive dechlorination with varying success. Different carbon sources were hypothesized to stimulate different extents of TCE reductive dechlorination. Ecological conditions that developed different dechlorination stages were investigated by quantitating Dehalococcoides 16S rRNA (Dhc) and reductive dehalogenase gene abundance, and by describing biogeochemical properties of laboratory columns in response to this biostimulation. Eight large columns (183 cm × 15.2 cm), packed with aquifer material from Hill AFB, Utah, that were continuously fed TCE for 7.5 years. Duplicate columns were biostimulated with whey or …
Development Of A Decision-Making Methodology To Design A Water Quality Monitoring Network, J. Keum, Jagath J. Kaluarachchi
Development Of A Decision-Making Methodology To Design A Water Quality Monitoring Network, J. Keum, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
The number of water quality monitoring stations in the USA has decreased over the past few decades. Scarcity of observations can easily produce prediction uncertainty due to unreliable model calibration. An effective water quality monitoring network is important not only for model calibration and water quality prediction but also for resources management. Redundant or improperly located monitoring stations may cause increased monitoring costs without improvement to the understanding of water quality in watersheds. In this work, a decision-making methodology is proposed to design a water quality monitoring network by providing an adequate number of monitoring stations and their approximate locations …
Biostimulation And Bioaugmentation To Enhance Reductive Dechlorination Of Tce In A Long-Term Flow Through Column Study, Joan E. Mclean, Jared Ervin, Jing Zhou, Darwin L. Sorensen, Ryan Dupont
Biostimulation And Bioaugmentation To Enhance Reductive Dechlorination Of Tce In A Long-Term Flow Through Column Study, Joan E. Mclean, Jared Ervin, Jing Zhou, Darwin L. Sorensen, Ryan Dupont
Civil and Environmental Engineering Faculty Publications
Large laboratory columns (15.2 cm diameter, 183 cm long) were fed with groundwater containing trichloroethylene (TCE), were biostimulated and bioaugmented, and were monitored for over 7.5 years. The objective of the study was to observe how the selection of the carbon and energy source, i.e., whey, Newman Zone® standard surfactant emulsified oil and Newman Zone nonionic surfactant emulsified oil, affected the rate and extent of dechlorination. Column effluent was monitored for TCE and its degradation products, redox indicators (nitrate-N, Fe(II), sulfate), and changes in iron mineralogy. Total bacteria and Dehalococcoides mccartyi strains were quantified using q-PCR. Complete dechlorination was only …
Particulate-Matter Emission Estimates From Agricultural Spring-Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, Christian C. Marchant, D. S. Jones, W. J. Bradford, G. E. Bingham, R L. Pfeiffer, J. H. Prueger, J. L. Hatfield
Particulate-Matter Emission Estimates From Agricultural Spring-Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, Christian C. Marchant, D. S. Jones, W. J. Bradford, G. E. Bingham, R L. Pfeiffer, J. H. Prueger, J. L. Hatfield
Civil and Environmental Engineering Faculty Publications
Particulate-matter (PM) emissions from a typical spring agricultural tillage sequence and a strip–till conservation tillage sequence in California’s San Joaquin Valley were estimated to calculate the emissions control efficiency (ηη) of the strip–till conservation management practice (CMP). Filter-based PM samplers, PM-calibrated optical particle counters (OPCs), and a PM-calibrated light detection and ranging (LIDAR) system were used to monitored upwind and downwind PM concentrations during May and June 2008. Emission rates were estimated through inverse modeling coupled with the filter and OPC measurements and through applying a mass balance to the PM concentrations derived from LIDAR data. Sampling irregularities and errors …
Remediation Of Polycyclic Aromatic Hydrocarbons In Soil Using Hemoglobin-Catalytic Mechanism, Guyoung Kang, Kapsung Park, Jaechang Cho, David King Stevens, Namhyun Chung
Remediation Of Polycyclic Aromatic Hydrocarbons In Soil Using Hemoglobin-Catalytic Mechanism, Guyoung Kang, Kapsung Park, Jaechang Cho, David King Stevens, Namhyun Chung
Civil and Environmental Engineering Faculty Publications
It is suggested in this paper that recalcitrant organopollutants can be degraded efficiently by a hemoglobin-catalytic reaction in the presence of hydrogen peroxide (i.e., H2O2). The catalytic mechanism was studied with 5-aminosalicylic acid (5-ASA) as a compound for oxidation. Various evidence suggests that the catalytic mechanism is very similar to those of horseradish peroxidase and lignin peroxidase. The catalytic intermediates are known to oxidize various chemicals, indicating that the intermediates of hemoglobin can nonspecifically degrade many different types of organopollutants. To prove the hypothesis, an attempt was made to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated field soil. The results showed that …
Can Suspended Fine Sediment Transport In Shallow Lakes Be Predicted Using Mvrvm With Limited Observations?, H. A. Batt Ph.D., David King Stevens
Can Suspended Fine Sediment Transport In Shallow Lakes Be Predicted Using Mvrvm With Limited Observations?, H. A. Batt Ph.D., David King Stevens
Civil and Environmental Engineering Faculty Publications
The study of sediment transport in water natural bodies is a challenging task. There have been several attempts to describe sediment mathematically using hydraulic characteristics of water bodies. Most researchers who developed empirical formulas to describe sediment transport performed laboratory experiments with assumptions that did not take into account variations of hydraulic parameters and the fine sediment sizes that are part of this phenomenon. Recently, new approaches for studying sediment transport have been developed involving the use of machine-learning algorithms that have proven accuracy and efficiency in predicting sediment transport. A novel machinelearning method, the Multivariate Relevance Vector Machine (MVRVM), …