Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

2019

Series

Earth Sciences

Institution
Keyword
Publication
File Type

Articles 1 - 30 of 47

Full-Text Articles in Engineering

Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi Dec 2019

Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi

Civil and Environmental Engineering and Construction Faculty Research

Study region: Sacramento San Joaquin River Basin, California Study focus: The study forecasts the streamflow at a regional scale within SSJ river basin with largescale climate variables. The proposed approach eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962–2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors …


Small Ruminant Health Intervention Calendar In Ethiopia, Mesfin Mekonnen, Ayalew Assefa, Tesfalem Nane, Firdawok Ayele, Asrat Arke, Belay Elias, Barbara Wieland Dec 2019

Small Ruminant Health Intervention Calendar In Ethiopia, Mesfin Mekonnen, Ayalew Assefa, Tesfalem Nane, Firdawok Ayele, Asrat Arke, Belay Elias, Barbara Wieland

Daugherty Water for Food Global Institute: Faculty Publications

Contents

1 Background................................................................................................... 3
2 Developing the health intervention calendar............................................................ 4
The treatment calendar ......................................................... 4 Applying the calendar..................................................................... 5 4 References................................................................... 8


Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi Nov 2019

Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi

Publications and Research

Land surface temperature (LST) plays a key role in the surface energy budget computation and land surface process studies. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua and Terra satellites provide comprehensive global LST estimates at a fine spatial resolution. The MODIS products were recently upgraded to Collection 6, and shown to be more accurate than its predecessor Collection 5 products. In this study, LST and its variability have been examined across India from Collection 6 of the Aqua MODIS data at 0.05° spatial resolution for the period of 2003 to 2017. All-India mean LST characteristics show distinctive …


Extraction And Visualization Of Orientation Data From Virtual Geologic Surfaces With Matlab®, Avery J. Welker, John Patrick Hogan, Andreas Eckert Nov 2019

Extraction And Visualization Of Orientation Data From Virtual Geologic Surfaces With Matlab®, Avery J. Welker, John Patrick Hogan, Andreas Eckert

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

High-resolution visualization of surfaces of geologic interest, at a multitude of scales, using 3D point cloud technologies provides an opportunity to analyze spatial relationships of surfaces using orientation data. We present a MATLAB® script that produces planar geologic attitude data (e.g., strike, dip, and dip-direction data) from 3D datasets (e.g., point clouds, 3D scanning). The method utilizes Cartesian coordinates of triangular planar surfaces and converts them into matrices of conventional geologic attitude data. Spatial relationships among data points can be investigated, using polar tangent diagrams, stereographic analysis, or geologic curvature analysis. We utilize this script to create "synthetic" graphical plots …


Removal Of Selected Pharmaceuticals And Personal Care Products In Wastewater Treatment Plant In Jordan, Othman Al-Mashaqbeh, Diya Alsafadi, Sahar Dalahmeh, Shannon L. Bartelt-Hunt, Daniel D. Snow Sep 2019

Removal Of Selected Pharmaceuticals And Personal Care Products In Wastewater Treatment Plant In Jordan, Othman Al-Mashaqbeh, Diya Alsafadi, Sahar Dalahmeh, Shannon L. Bartelt-Hunt, Daniel D. Snow

Nebraska Water Center: Faculty Publications

The largest wastewater treatment plant in Jordan was monitored in the summer to determine the removal of pharmaceuticals and personal care products (PPCPs). Grab samples were collected from the influent and effluent of As-Samra Wastewater Treatment Plant (WWTP). Liquid chromatography and tandem mass spectrometry (LC–MS/MS) were utilized to determine the concentrations of 18 compounds of pharmaceuticals and personal care products (PPCPs). The results showed that 14 compounds were detected in the collected samples from the influent and effluent of As-Samra WWTP. These compounds are 1,7-dimethylxanthine, amphetamine, acetaminophen, caffeine, carbamazepine, cimetidine, cotinine, diphenhydramine, methylenedioxymethamphetamine (MDMA), morphine, phenazone, sulfamethazine, sulfamethoxazole, thiabendazole, and …


Long-Term Changes Of Open-Surface Water Bodies In The Yangtze River Basin Based On The Google Earth Engine Cloud Platform, Yue Deng, Wei-Guo Jiang, Zhenghong Tang, Ziyan Ling, Zhifeng Wu Sep 2019

Long-Term Changes Of Open-Surface Water Bodies In The Yangtze River Basin Based On The Google Earth Engine Cloud Platform, Yue Deng, Wei-Guo Jiang, Zhenghong Tang, Ziyan Ling, Zhifeng Wu

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

The spatiotemporal changes of open-surface water bodies in the Yangtze River Basin (YRB) have profound influences on sustainable economic development, and are also closely relevant to water scarcity in China. However, long-term changes of open-surface water bodies in the YRB have remained poorly characterized. Taking advantage of the Google Earth Engine (GEE) cloud platform, this study processed 75,593 scenes of Landsat images to investigate the long-term changes of open-surface water bodies in the YRB from 1984 to 2018. In this study, we adopted the percentile-based image composite method to collect training samples and proposed a multiple index water detection rule …


Modeling Irrigation Behavior In Groundwater Systems, Timothy Foster, Nicholas Brozovic, Adrian P. Butler Aug 2019

Modeling Irrigation Behavior In Groundwater Systems, Timothy Foster, Nicholas Brozovic, Adrian P. Butler

Daugherty Water for Food Global Institute: Faculty Publications

Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas …


Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra Aug 2019

Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Global demand for livestock products is rising, resulting in a growing demand for feed and potentially burdening freshwater resources to produce this feed. To offset this increased pressure on water resources, the environmental performance of livestock sector should continue to improve. Over the last few decades, product output per animal and feedstuff yields in the US have improved, but before now it was unclear to what extent these improvements influenced the water productivity (WP) of the livestock products. In this research, we estimate changes in WP of animal products from 1960 to 2016. We consider feed conversion ratios (dry matter …


Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer Aug 2019

Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer

School of Natural Resources: Dissertations, Theses, and Student Research

The Midwestern United States is vulnerable to eutrophic conditions from high nutrient concentrations. Recommendations for nonpoint source pollution management include runoff treatment (i.e., filter strips, riparian buffers) and in-situ lake treatment practices (i.e., aluminum sulfate (alum) treatments, aeration, up/downdraft pumping, floating treatment wetlands). Floating treatment wetlands (FTWs) are an innovative wetland design for nutrient removal from nonpoint sources and provide a unique in-situ treatment. Best management practice studies have commonly focused on adjacent to water practices, which have resulted in a gap for guidance for in-situ treatment placement and design. Therefore, the objectives of this project were to (1) Quantify …


Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads, Taylor J. Knickerbocker Aug 2019

Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads, Taylor J. Knickerbocker

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Estimates of rare seismic hazard are essential for the resilience of critical infrastructure and facilities. However, these estimates are highly uncertain at long return periods due to the lack of observed earthquake records. Several ground motion prediction equations have been proposed to close this gap and estimate rare seismic demands; however, these models were developed based on more moderate earthquake records and can yield physically unrealizable ground motions when extrapolated to long return periods. For this reason, seismologists have proposed using precariously balanced rocks (PBRs) as a way to constrain rare seismic hazard. PBRs are a type of fragile geologic …


Perchlorate Behavior In The Context Of Black Carbon And Metal Cogeneration Following Fireworks Emission At Oak Lake, Lincoln, Nebraska, Usa, Manish Kumar, Daniel D. Snow, Yusong Li, Patrick Shea Jul 2019

Perchlorate Behavior In The Context Of Black Carbon And Metal Cogeneration Following Fireworks Emission At Oak Lake, Lincoln, Nebraska, Usa, Manish Kumar, Daniel D. Snow, Yusong Li, Patrick Shea

Nebraska Water Center: Faculty Publications

The imprints of fireworks displays on the adjacent water body were investigated from the perspective of cogeneration of black carbon, metals and perchlorate (ClO4). In particular, the mixing and dissipation of ClO4 were studied at Oak Lake, Lincoln, Nebraska, following fireworks displays in 2015 and 2016. Following the display, ClO4 concentration in the water increased up to 4.3 μg/L and 4.0 μg/L in 2015 and 2016, respectively. A first-order model generally provided a good fit to the measured perchlorate concentrations from which the rate of dissipation was estimated as 0.07 d–1 in …


Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota Jun 2019

Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota

Civil Engineering Faculty Publications and Presentations

This study incorporates antecedent (preceding) soil moisture into forecasting streamflow volumes within the North Platte River Basin, Colorado/Wyoming (USA). The incorporation of antecedent soil moisture accounts for infiltration and can improve streamflow predictions. Current Natural Resource Conservation Service (NRCS) forecasting methods are replicated, and a comparison is drawn between current NRCS forecasts and proposed forecasting methods using antecedent soil moisture. Current predictors used by the NRCS in regression-based streamflow forecasting include precipitation, streamflow persistence (previous season streamflow volume) and snow water equivalent (SWE) from SNOTEL (snow telemetry) sites. Proposed methods utilize antecedent soil moisture as a predictor variable in addition …


Development Of An Rfid Tracking System For Coarse Sediment Transport In A Flume Setting, Peter Mahoney Jr. Jun 2019

Development Of An Rfid Tracking System For Coarse Sediment Transport In A Flume Setting, Peter Mahoney Jr.

ENGS 88 Honors Thesis (AB Students)

Development of an RFID Tracking System for Coarse Sediment Transport in a Flume Setting

Peter E. Mahoney

Professor Carl Renshaw

Understanding how sediment moves through a fluvial system has important implications for the study of river systems, sediment flux, and flood events. Over the past decade, RFID (radio frequency identification) technology has emerged as a useful method for tracking the movement and transport of coarse sediment clasts. This approach has been used to measure the transport of large clasts in mid-sized streams, ephemeral channels, and laboratory flume settings. However, this research utilized finite transport of sediment and focused on accurately …


Next-Generation Rainfall Idf Curves For The Virginian Drainage Area Of Chesapeake Bay, Xixi Wang, Xiaomin Yang, Zhaoyi Cai Jun 2019

Next-Generation Rainfall Idf Curves For The Virginian Drainage Area Of Chesapeake Bay, Xixi Wang, Xiaomin Yang, Zhaoyi Cai

Civil & Environmental Engineering Faculty Publications

Probability-based intensity-duration-frequency IDF curves are needed but currently lacking for Department of Defense DoD to construct and manage its infrastructure in changing climate. The objectives of this project were to 1 develop an innovative approach for considering rainfall non-stationarity in developing such IDF curves and 2 apply this approach to the state of Virginia. In this regard, the observed data on 15-min rainfall at 57 gauges and the precipitations projected by twelve pairs of Regional Climate Model RCM and Global Circulation Model GCM were used. For a given gauge or watershed, in terms of fitting the empirical exceedance probabilities, a …


Development Of Digital Bathymetry Maps For Lakes Azuei And Enriquillo Using Sonar And Remote Sensing Techniques, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Jorge Gonzalez May 2019

Development Of Digital Bathymetry Maps For Lakes Azuei And Enriquillo Using Sonar And Remote Sensing Techniques, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Jorge Gonzalez

Publications and Research

This article presents an improved algorithm for optimization and development of a digital bathymetric model (DBM) for Lake Azuei (LA) (Haiti) and Lake Enriquillo (LE) (Dominican Republic) using the ANUDEM method. Both sonar data and contour lines of the lakes’ layout extracted using Landsat imagery were compiled for bathymetry development. We show that the performance of the ANUDEM method was strongly dependent on the density and irregularity of the spatial distribution of the data. Changing the resolution of the output grids and deriving auxiliary topographically corrected contours improved the ANUDEM performance and minimized the systematic errors of the method. Statistical …


A Cooperative Overlay Approach At The Physical Layer Of Cognitive Radio For Digital Agriculture, Abdul Salam, Umit Karabiyik May 2019

A Cooperative Overlay Approach At The Physical Layer Of Cognitive Radio For Digital Agriculture, Abdul Salam, Umit Karabiyik

Faculty Publications

In digital agriculture, the cognitive radio technology is being envisaged as solution to spectral shortage problems by allowing agricultural cognitive users to co-exist with noncognitive users in the same spectrum on the field. Cognitive radios increase system capacity and spectral efficiency by sensing the spectrum and adapting the transmission parameters. This design requires a robust, adaptable and flexible physical layer to support cognitive radio functionality. In this paper, a novel physical layer architecture for cognitive radio based on cognition, cooperation, and cognitive interference avoidance has been developed by using power control for digital agriculture applications. The design is based on …


Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah Apr 2019

Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah

Faculty Publications

The extra quantities of wastewater entering the pipes can cause backups that result in sanitary sewer overflows. Urban underground infrastructure monitoring is important for controlling the flow of extraneous water into the pipelines. By combining the wireless underground communications and sensor solutions, the urban underground IoT applications such as real time wastewater and storm water overflow monitoring can be developed. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. It has been shown that the communication range of up to 4 kilometers can be achieved from an underground …


Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah Apr 2019

Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah

Civil Engineering Faculty Publications and Presentations

This study reports the preliminary results from a statistical screening of tree-ring width records from the International Tree-Ring Data Bank (ITRDB), to evaluate the strength of the hydrological signal, in dendrochronological records from the Tennessee Valley. We used United States Geological Survey (USGS) streamflow data from 11 gages, within the Tennessee Valley, and regional tree-ring chronologies, to analyze the dendroclimatic potential of the region, and create seasonal flow reconstructions. Prescreening methods included correlation, date, and temporal stability analysis of predictors to ensure practical and reliable reconstructions. Seasonal correlation analysis revealed that large numbers of regional tree-ring chronologies were significantly correlated …


An Underground Radio Wave Propagation Prediction Model For Digital Agriculture, Abdul Salam Apr 2019

An Underground Radio Wave Propagation Prediction Model For Digital Agriculture, Abdul Salam

Faculty Publications

Underground sensing and propagation of Signals in the Soil (SitS) medium is an electromagnetic issue. The path loss prediction with higher accuracy is an open research subject in digital agriculture monitoring applications for sensing and communications. The statistical data are predominantly derived from site-specific empirical measurements, which is considered an impediment to universal application. Nevertheless, in the existing literature, statistical approaches have been applied to the SitS channel modeling, where impulse response analysis and the Friis open space transmission formula are employed as the channel modeling tool in different soil types under varying soil moisture conditions at diverse communication distances …


A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu Apr 2019

A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu

Earth and Environmental Sciences Faculty Publications

Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the …


Underground Environment Aware Mimo Design Using Transmit And Receive Beamforming In Internet Of Underground Things, Abdul Salam Apr 2019

Underground Environment Aware Mimo Design Using Transmit And Receive Beamforming In Internet Of Underground Things, Abdul Salam

Faculty Publications

In underground (UG) multiple-input and multiple-output (MIMO), the transmit beamforming is used to focus energy in the desired direction. There are three different paths in the underground soil medium through which the waves propagates to reach at the receiver. When the UG receiver receives a desired data stream only from the desired path, then the UG MIMO channel becomes three path (lateral, direct, and reflected) interference channel. Accordingly, the capacity region of the UG MIMO three path interference channel and degrees of freedom (multiplexing gain of this MIMO channel requires careful modeling). Therefore, expressions are required derived the degrees of …


Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight Apr 2019

Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Land subsidence as a result of groundwater overpumping in the San Joaquin Valley, California, is associated with the loss of groundwater storage and aquifer contamination. Although the physical processes governing land subsidence are well understood, building predictive models of subsidence is challenging because so much subsurface information is required to do so accurately. For the first time, we integrate airborne electromagnetic data, representing the subsurface, with subsidence data, mapped by interferometric synthetic aperture radar (InSAR), to model deformation. By combining both data sets, we are able to solve for hydrologic and geophysical properties of the subsurface to effectively model the …


Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle Mar 2019

Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle

Civil and Environmental Engineering Faculty Publications and Presentations

Ecosystem water-use efficiency (WUE) is defined as the ratio of carbon gain (i.e., gross primary productivity; GPP) to water consumption (i.e., evapotranspiration; ET). WUE is markedly influential on carbon and water cycles, both of which are fundamental for ecosystem state, climate and the environment. Drought can affect WUE, subsequently disturbing the composition and functionality of terrestrial ecosystems. In this study, the impacts of drought on WUE and its components (i.e., GPP and ET) are assessed across the Contiguous US (CONUS) at fine spatial and temporal resolutions. Soil moisture simulations from land surface modeling are utilized to detect and characterize agricultural …


Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth Feb 2019

Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth

Plant and Soil Sciences Faculty Publications

Stony soils are distributed all over the world. The study of their characteristics has gained importance lately due to their increasing use as agricultural soils. The effect that rock fragments exert on the soil hydraulic properties is difficult to measure in situ, and is usually derived from the fine earth properties. However, the corrections used so far do not seem accurate for all types of stony soils. Our objective was to assess the adequacy of estimating the hydraulic properties of a stony soil from the fine earth ones by correcting the latter by the volume occupied by rock fragments. To …


A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak Feb 2019

A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak

Faculty Publications

The realization of Internet of Underground Things (IOUT) relies on the establishment of reliable communication links, where the antenna becomes a major design component due to the significant impacts of soil. In this paper, a theoretical model is developed to capture the impacts of change of soil moisture on the return loss, resonant frequency, and bandwidth of a buried dipole antenna. Experiments are conducted in silty clay loam, sandy, and silt loam soil, to characterize the effects of soil, in an indoor testbed and field testbeds. It is shown that at subsurface burial depths (0.1-0.4m), change in soil moisture impacts …


Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen Feb 2019

Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

Green water––rainfall over land that eventually flows back to the atmosphere as evapotranspiration––is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water––groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), …


Carboxylic Acids Accelerate Acidic Environment-Mediated Nanoceria Dissolution, Robert A. Yokel, Matthew L. Hancock, Eric A. Grulke, Jason M. Unrine, Alan K. Dozier, Uschi M. Graham Feb 2019

Carboxylic Acids Accelerate Acidic Environment-Mediated Nanoceria Dissolution, Robert A. Yokel, Matthew L. Hancock, Eric A. Grulke, Jason M. Unrine, Alan K. Dozier, Uschi M. Graham

Pharmaceutical Sciences Faculty Publications

Ligands that accelerate nanoceria dissolution may greatly affect its fate and effects. This project assessed the carboxylic acid contribution to nanoceria dissolution in aqueous, acidic environments. Nanoceria has commercial and potential therapeutic and energy storage applications. It biotransforms in vivo. Citric acid stabilizes nanoceria during synthesis and in aqueous dispersions. In this study, citrate-stabilized nanoceria dispersions (∼4 nm average primary particle size) were loaded into dialysis cassettes whose membranes passed cerium salts but not nanoceria particles. The cassettes were immersed in iso-osmotic baths containing carboxylic acids at pH 4.5 and 37 °C, or other select agents. Cerium atom material …


Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki Jan 2019

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki

Publications and Research

In this report, we present historical time series of surface area, volume, and elevation for lakes Azuei (Haiti) and Enriquillo (Dominican Republic). The intention is to present a history of the lakes’ levels for both bodies of water as derived from Landsat imagery that is augmented by reports and narratives that reach further back in time. We also summarize lake level time series data collected and developed through various other efforts and compare these data sets to our time series. The time series contains 45 years’ worth of data ranging from 1972 to 2017 which we developed from Landsat imagery …


Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic Jan 2019

Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Understanding how irrigation is used across agricultural landscapes is essential to support efforts to grow more food while reducing pressures on limited freshwater resources. However, to date, few studies have analyzed the underlying spatial and temporal variability in farmers’ individual water use decisions at a landscape scale.Wecompare estimates of irrigation water requirements derived using state-of-the-art remote sensing models with metered abstraction records for 1400 fields over a 13 year period in the US state of Nebraska, one of the world’s most intensively irrigated agricultural regions. Weshow that farmers’ observed water use decisions often diverge significantly from biophysical estimates of crop …


Experiment Study Of Lateral Unloading Stress Path And Excess Pore Water Pressure On Creep Behavior Of Soft Soil, Wei Huang, Kejun Wen, Dongsheng Li, Xiaojia Deng, Lin Li, Haifei Jiang, Farshad Amini Jan 2019

Experiment Study Of Lateral Unloading Stress Path And Excess Pore Water Pressure On Creep Behavior Of Soft Soil, Wei Huang, Kejun Wen, Dongsheng Li, Xiaojia Deng, Lin Li, Haifei Jiang, Farshad Amini

Civil and Architectural Engineering Faculty Research

The unloading creep behavior of soft soil under lateral unloading stress path and excess pore water pressure is the core problem of time-dependent analysis of surrounding rock deformation under excavation of soft soil. The soft soil in Shenzhen, China, was selected in this study. The triaxial unloading creep tests of soft soil under different initial excess pore water pressures (0, 20, 40, and 60 kPa) were conducted with the K0 consolidation and lateral unloading stress paths. The results show that the unloading creep of soft soil was divided into three stages: attenuation creep, constant velocity creep, and accelerated creep. The …