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22nd Environmental Engineering and Science Symposium__________________________________________________________

April 7, 2015

Department of Civil and Environmental Engineering

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Podium

Katherine A Stephens

Elucidating the role of anaerobic digestion of swine manure in nutrient and energy flows on

smallholder farms

In light of limited achievements in the United Nations (UN) 2015 Millennium Development Goal (MDG)

targeting environmental sustainability, there is a call to take more integrated approaches to developing

world interventions. This study proposes that viewing waste as a resource has the potential to affect

several factors underlying systemic poverty. Anaerobic digestion (AD) is an established sanitation

technology commonly applied in developed countries, which converts human or animal waste into: (1)

biogas, a clean form of household energy for both cooking and lighting, and (2) digestate, a stabilized

solid with bioavailable nutrients, which can be land applied as a biologically safe fertilizer. Although AD

has been tried in many parts of Sub-Saharan Africa (SSA), successful installations are sparse as

digesters have had mixed results in terms of biogas production and overall performance. Beyond

operational and infrastructural challenges, this lack of sustained adoption may partly stem from a lack of

information surrounding how animal waste differs in industrialized and developing countries (stemming

from very different animal diets), and how these differences influence AD performance. The present study

aims to characterize pig waste in SSA through critical literature review, and to identify potential solutions

to overcome barriers to wide scale application as an AD feedstock in SSA.

Justin Hutchison

Biocatalytic Perchlorate Reduction in Groundwater

Biocatalysts can target contaminants with specificity and high activity, as the biocatalysts have been

honed through evolution making them more efficient than the chemical and physical processes typically

used. The model contaminant, perchlorate, was selected as the focus of this research due to its stability

in aqueous environments, widespread contamination in the United States, and health risks. The

biocatalysts mimic the whole-cell biological process using perchlorate-reducing enzymes, perchlorate

reductase and chlorite dismutase, which can reduce perchlorate to innocuous chloride and molecular

oxygen. Biocatalysts were assayed in two groundwater sources from Iowa and Illinois. Biocatalysts

achieved maximum activity rates of 162.5 U/µg Mo in a buffered system and maintained robust

perchlorate degradation in groundwater, with maximum activity rates of 94% in Iowa GW and 82% in

Illinois GW as compared to buffered values. The biocatalysts were active over a range of temperatures

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and pHs and had preferential activity for perchlorate. Alone, practical electrons donors such as acetate

resulted in no observed reduction of perchlorate. However, with the addition of an electron shuttle,

ascorbic acid in a 5:1 molar ratio resulted in 32.1% reduction of perchlorate in the presence of oxygen.

This work demonstrated the potential for biocatalytic treatment of perchlorate in groundwater over a range

of concentrations corresponding to those found in drinking water sources to those at sites with industrial

and military contamination with minimal interference observed from the groundwater matrix.

Artin Laleian

A hybrid pore-scale and continuum-scale model for biofilm growth in porous media

Subsurface pore structure is altered by the presence of biofilm, affecting solute transport within the

porous medium. While pore-scale numerical models capture these important dynamics, they are

computationally expensive, making them infeasible for large domains, or when details of the pore

geometry are unknown. In some applications, such as modeling groundwater contaminant plumes, hybrid

models may effectively reduce computational expense while preserving accuracy. Because most reaction

occurs along the plume fringe, this region is resolved at the pore-scale with a fine grid spacing. Away

from the mixing zone, a continuum approximation is sufficient and less computationally intensive. We

present a hybrid two-dimensional model for biofilm growth in which the pore-scale and continuum-scale

velocity fields are determined with lattice Boltzmann and finite volume methods, respectively, the solute

concentration field is determined with a finite difference method, solute utilization is determined by dual

Monod kinetics, and biofilm spreading is determined by a cellular automaton method. A mortar space

method is employed on subdomain boundaries to ensure continuity of fluid and solute mass. We find the

hybrid model has a significantly reduced CPU run time relative to a complete pore-scale model, while

producing a consistent result in terms of solute utilization and biofilm accumulation.

Srinidhi Balasubramanian

Developing Chemical Transport Model Ready Emissions for Predictions of Regional Air Quality

Trends

Chemical Transport Models (CTMs) are widely used to assess impacts of emissions of air pollutants on

regional air quality. Accurate emission inventories are central to developing accurate CTM predictions.

For the United States (U.S.), annual, county-scale emissions are available from the National Emissions

Inventory (NEI). Additional efforts are required to make these emissions CTM-ready at higher spatial and

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temporal resolutions by using an emissions processor like the Spare Matrix Operator Kernel Emissions

(SMOKE) model. This presentation will provide an overview of the sources and trends in air pollutant

emissions in the U.S. for the year 2011 and an effort to use the NEI-SMOKE approach for a study aimed

at understanding the impact of NH3 emissions from fertilizer usage on ambient particulate matter

formation and deposition of reactive nitrogen in the Midwest U.S.

Within SMOKE, emissions are allocated to spatial resolutions (4 km x 4 km to 32 km x 32 km) required by

CTMs using spatial surrogates. Emissions are then allocated to the hourly scale based on temporal

factors that identify seasonality in emissions. Chemical speciation profiles are applied to account for

transformation of precursor pollutants. Emissions related to area, non-road and point sources are

obtained from NEI, while emissions from mobile and biogenic sources are dynamically estimated within

SMOKE. The NEI-SMOKE approach in developing CTM-ready emission inputs is advantageous as

emission inputs and ancillary data such as spatial surrogates and temporal factors are available through

the U.S. Environmental Protection Agency. Challenges however include paucity in emissions data for

some years, cumbersome efforts for processing spatial surrogates and computational time needed for

annual simulations. The NEI-SMOKE approach will be integrated with previous efforts that resulted in

improved ammonia emission predictions from fertilizer usage to support improved predictions of air

quality and deposition of reactive nitrogen in the Midwest U.S.

Raul Tenorio

Photogeneration of reactive oxygen species (ROS) by extracellular organic matter (EOM) in

Chlamydomonas reinhardtii photobioreactor cultures

Algal technologies have shown promise as tertiary wastewater treatment processes capable of reducing

nitrogen and phosphorous to meet increasingly stringent regulatory limits. Past research has shown that

irradiation of green microalgae under UV and visible light promotes enhanced transformation of trace

organic contaminants (e.g., PPCPs) compared to direct photolysis alone. The detection of singlet oxygen

(1O2) and hydroxyl radicals (•OH) in irradiated microalgae suspensions has lead researchers to believe

reactive oxygen species (ROS) generation is the source of the enhanced contaminant degradation.

Microalgae excrete extracellular organic matter (EOM) as metabolic byproducts that can act as

photosensitizers for ROS generation via similar mechanisms reported for dissolved organic matter (DOM)

derived from decayed terrestrial organic matter. This presentation will report on measurements of ROS

production in solutions of EOM extracted from pure batch cultures of C. reinhardtii. Results show

increasing steady-state levels of excited triplet dissolved organic matter (3DOM), singlet oxygen, and

production of hydroxyl radicals under sunlight irradiation as biomass grows and EOM levels in the culture

increase. Changes in ROS were compared with changes in culture characteristics such as volatile

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suspended solids (VSS) and nutrient availability as well as EOM properties, including dissolved organic

carbon (DOC) and specific UV absorbance (SUVA254). EOM-sensitized ROS production in comparison

to other DOM sources will also be discussed along with implications for the fate of trace contaminants in

microalgae wastewater treatment systems.

Na Kyung Kim

Enrichment and characterization of microbial consortia degrading soluble microbial products

discharged from anaerobic methanogenic bioreactors

Soluble microbial products (SMP) produced in bioprocesses have been known as a main cause to lower

effluent quality and promote membrane fouling in water reclamation plants. In this study, a down-flow

hanging sponge (DHS) reactor was configured as a post-treatment process of anaerobic reactors to

biologically degrade SMP discharged from anaerobic reactors treating soft drink wastewater. The DHS

could successfully enrich microbial consortia and degrade SMP produced from the anaerobic reactors as

a sole substrate for a period >800 days. The microbial community composition and structure were

characterized using bacterial 16S rRNA gene pyrosequencing technology, and their correlation with

operational factors, such as hydraulic retention time (HRT), organic loading rate (OLR), and reactor

depths, was evaluated by performing redundancy analysis (RDA). On average, 68.9 to 87.5% SMP in

terms of soluble chemical oxygen demand (SCOD) was removed by the DHS reactor. Molecular weight

(MW) characterization by high performance liquid chromatography–size exclusion chromatography

revealed that a bimodal distribution of SMP with MW distribution of 13-17 kDa and <4 kDa was detected

in the influent of the DHS reactor. Between these two types of SMP, the small MW SMP were readily

degraded in the upper part of the reactor, whereas the large MW SMP were partially degraded in the

reactor. RDA of the microbial community at different phases and reactor depths showed that unclassified

Flavobacteria (25.9% in Phase V) and Saprospiraceae (30.1% in Phase V) were strongly correlated to

OLR, suggesting their active involvement in SMP removal. Different microbial diversity along with the

depth of the reactor implies that stratified microbial communities could participate in the process of SMP

degradation. Taken together, these observations indicate that biodegradation of SMP by selectively

enriched microbial community in the DHS reactor was effective enough to be incorporated as a strategy

controlling SMP for water reclamation systems.

Wangki Yuen

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Ambient Plume Opacity Measurements Using a Video Camera Recorder and Digital Optical

Method

The applicability of Digital Optical Method (DOM) to measure plume opacity with a digital video camera

recorder (camcorder) in a smokestack was tested. Camcorders have the advantage of obtaining real-time

digital images, thus allowing continuous measurement of plume opacity and its temporal variation. They

also allow keeping an archival record of plume opacity events. A Canon camcorder was first calibrated

using two methods: by either varying the exposure value compensation of the camcorder, or varying the

radiance of a surface. The camcorder was then used in the field in July 9, 2013 to measure plume

opacity. A smoke generator was used that provided plumes of controlled opacity values. Opacity was

measured with a transmissometer inside the smoke generator stack. These opacity measurements were

used as the standard for testing the applicability of DOM for the camcorder to determine plume opacity.

Measurements were made during daytime and nighttime. Still images were extracted once every two

minutes for the entire videos and every second for select one minute periods to test this system at

different time resolutions. Each image was analyzed using DOM analysis software. Daytime results from

images obtained every two minutes show that camcorder derived opacity values have an average

absolute bias of 3.4% for black plumes and 5.1% for white plumes. Camcorder opacity measurements at

one-second time resolution have an average absolute bias <6% for black plumes and <4% for white

plumes. Nighttime results show that camcorder opacity values for black plumes have average absolute

bias of 3.2% at low opacity (<45%), but consistently lower than transmissometer values by an average

absolute bias of 16.5% at high opacity (>65%). These results demonstrate that camcorder can be used

for measuring plume opacity continuously during daytime, while nighttime measurements need further

investigation on the effect of surrounding lighting conditions.

Tianye Sun

Use of Historical Measurements to Constrain Black Carbon Emission Inventory of the United

States from 1960s to 2000s

We use historical coefficient of haze measurements in California and New Jersey to constrain the black

carbon (BC) emission inventory for 1960s-2000s. We study the relationship between emissions and

ambient air concentrations of BC using the Community Atmosphere Model. When formulating the

relationship into matrices that allow reconstruction of ambient concentration with emission inventory, we

account for the error in model meteorology and adjust it with measurements from NASA. We also apply

Heating Degree Days (HDDs) data to estimate seasonal variation in emissions, as observed from the

concentrations. However, HDDs does not fully explain the seasonal variation trend of the measurement.

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Potential errors in historical emissions are identified by analyzing discrepancy between reconstructed and

measured BC. Acknowledging the resolution difference between the reconstructed concentrations based

on global model simulation and and the urban measurements, we rely more on the discrepancies in

trends than that in absolute discrepancies. We find that the magnitude of observations was decreasing

throughout this period of time, while the reconstructed concentrations peaked in the 1980s. The fuel uses

and emission factors for each technology division and sector of BC emission inventory in SPEW

(Speciated Pollutant Emissions Wizard) are analyzed to address the error indication from the

measurements. A modified emission inventory for the period 1960-2000 is presented.

Cheryl Weyant

Black Carbon Emissions from Associated Natural Gas Flaring

Approximately 150 billion cubic meters (BCM) of associated natural gas is flared and vented in the world,

annually, emitting greenhouse gases and other pollutants with no energy benefit. Based on estimates

from satellite observations, the United States flares about 7 BCM of gas, annually (the 5th highest flaring

volume worldwide). The volume of gas flared in the US is growing, largely due to flaring in the Bakken

formation in North Dakota.

Black carbon (BC), a combustion by-product from gas flaring, is a short-term climate pollutant that

absorbs shortwave radiation both in the atmosphere and on snow and ice surfaces. Flaring may be a

significant source of global BC climate effects. For example, modeling estimates suggest that associated

gas flares are the source of a significant percentage of BC surface concentrations in the Arctic, where

BC-induced ice melting occurs. However, there are no direct field measurements of BC emission factors

from associated gas flares. Emission measurements of BC that include a range of flaring conditions are

needed to ascertain the magnitude of BC emissions from this source.

Over one hundred flare plumes were sampled in the Bakken formation using a small aircraft. Methane,

carbon dioxide, and BC were measured simultaneously, allowing the calculation of BC mass emission

factors using the carbon balance method. BC was measured using two methods; optical absorption was

measured using a Particle Soot Absorption Photometer (PSAP) and BC particle number and mass

concentrations were measured with a Single Particle Soot Photometer (SP2). Simultaneous sampling of

BC absorption and mass allows for the calculation of the BC mass absorption cross-section.

Results indicate that emission factor variability between flares in the region is significant; there are two

orders of magnitude variation in the BC emission factors.

Yun Shen

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Effects of continuous exposure to chlorination on mechanical and structural properties of

simulated drinking water biofilm

Biofilms, ubiquitous in drinking water distribution system (DWDS), could deteriorate drinking water quality

by hosting and releasing pathogens. USEPA required residual chlorine in DWDS to control the biofilms.

For improving the current knowledge of biofilm disinfection mechanisms in DWDS, the mechanical and

structural change of biofilms during long-term exposure of disinfectant was investigated. Biofilms used in

this study were developed from groundwater on PVC surfaces. After one year of growing period, these

biofilms were exposed to 4 mg/L of monochloramine or free chlorine under both hydraulic shearing and

static conditions, respectively. Atomic force microscope (AFM) and optical coherence tomography (OCT)

was used to determine the elasticity and structure. After 1 month of disinfectant exposure made the

biofilm surface became 2~7 times less elastic comparing with biofilms before disinfection. However, by

continuously exposing the biofilms to disinfectant for longer time, the elasticity of biofilms was recovered

to 1~3 times less elastic comparing with biofilms without treatment. OCT results did not show obvious

removal of biofilms under disinfectant exposure under all the experimental conditions. Under static

conditions, biofilms still kept same thickness and roughness with exposure of disinfectant. Under

hydraulic shearing condition, the decrease of biofilm roughness occurred during monochloramine

exposure process, while free chlorine did not change biofilm structure. This study identified the effect of

residual chlorine in DWDS on the mechanical and structural properties of biofilms, which will provide

information for biofilms control.

Brian D. Shoener

Advancing AnMBR design by identifying a pathway for sustainable technology innovation

The primary goal of wastewater treatment plants (WWTPs) is to safeguard public and environmental

health. Regulatory agencies help ensure protection of the local environment and public wellbeing through

discharge limits, but WWTPs continue to contribute to broader environmental impacts outside the purview

of NPDES permitting. A reduction in the life cycle environmental impacts of a WWTP can be achieved by

shifting away from conventional energy-intensive aerobic processes to energy-producing anaerobic

technologies (ATs). Of the current ATs, anaerobic membrane bioreactors (AnMBRs) show promise

because they reliably remove COD and provide a robust solids barrier. Given that this technology is early

in development, its successful commercialization will depend on strategic research and investment to

address critical barriers to system sustainability. In this study, quantitative sustainable design was used to

traverse a broad landscape of design and operational decisions to elucidate the economic and

environmental implications of AnMBR development pathways. By integrating cost analysis, life cycle

assessment, uncertainty and sensitivity analyses, this methodology was able to identify priorities for

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future research and to identify sub-sets of designs that possess fundamental barriers making them

uncompetitive. Finally, a technology roadmap for AnMBR development was established to align

treatment, economic, and environmental performance along more sustainable trajectories.

Amy Benitez

Implications of Transitioning to Green Infrastructure: A Quantitative Sustainability Assessment

of Urban Storm Water Management The implementation of green infrastructure (G.I.) as a means to reduce storm water through infiltration,

evapotranspiration, and reuse is being implemented in municipalities to reduce wastewater treatment

loads (in the case of combined sewer systems) and pollution of surface water. Although G.I. technologies

are becoming increasingly common and are propounded as being universally more sustainable than grey

infrastructure, the economic and environmental implications of transitioning to green infrastructure are

unique to each municipality and project. Many sustainability assessments have been completed in the

literature comparing green and grey infrastructure, but what is lacking is a fundamental understanding of

how design and operational decisions influence the sustainability of a community as well as drainage

infrastructure. This work will elucidate sustainability implications of design decisions, including costs and

indirect impacts of green and grey infrastructure, in order to inform urban storm water management

decision making in the city of Chicago. An environmental assessment will be completed using life cycle

assessment methodology, construction and design data, remote sensing, and data from the literature.

Further, an economic analysis will quantify the cost of implementation, cost of treatment, and changes in

surrounding property values. This will be completed through the examination of public records and by

drawing from related studies in the literature. By quantifying environmental, economic, and social

impacts, a triple bottom line assessment will be completed for Chicago’s storm water management

options to help navigate tradeoffs across and within dimensions of sustainability.

Mengwei Han

Reduction of Recalcitrant Pollutants with Re Complex Catalysis and Mechanism Study

Previous work in our group has demonstrated the effectiveness of Rhenium (Re) based catalyst in

reduction of perchlorate. (citation) However, during the synthesis process, cis- and trans- isomers of the

complex appeared at equal possibility, which later displayed distinct catalytic behaviors, with trans-

isomers being the desirable product. Albeit inter-conversion between cis- and trans- isomers can be

controlled through manipulation of synthetic conditions, interests lie in diminishing the formation of cis-

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isomers, which is achievable by adding motifs to the amino-acid based ligands. Symmetry of the Re

complex is broken due to chirality of substituted ligands, which gives rise to a series of intriguing synthetic

features, including the absolute elimination of cis-isomers in final products and the appearance of new

trans-enantiomers with different catalytic efficiency. In this presentation, we will report synthesis and

characterization of the Re complexes as well as their properties caused by modified ligands.

Homogeneous model reaction and heterogeneous engineering application of these complexes will also

be covered.

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Poster

Richa Sehgal

Using DNDC model for estimating Nitrous Oxide and Ammonia emissions from fertilized fields in

mid-west states of Illinois, Indiana and Ohio

In this study NH3 and N2O emission flux from chemical fertilizer usage in the mid-west states of United

States is simulated. The study domain consists of three mid-west states in Unites States, i.e. Illinois,

Indiana and Ohio. These are major producers of corn, soybean and winter wheat and hence provide a

good domain to estimate the emissions of N2O and NH3.

Denitrification – Decomposition (DNDC) model, which is a process oriented agro ecosystem model is

used to estimate direct N2O and NH3 emissions from cropland in these mid- west states. The model

predicts C and N biogeochemistry in agricultural ecosystems at site scale.

The 14 monitoring stations where the simulation is evaluated are Columbus, Jackson, Muck Crops and

Northwestern in Ohio; Belleville, Champaign, Peoria, Springfield and St. Charles in Illinois; and Farmland

(DPAC), Wanatah (PPAC), Butlerville (SEPAC) and Lafayette (TPAC) in Indiana.

At each of the weather stations, a grid of size 4km x 4km for Indiana and Illinois and a grid of size 12km x

12km for Ohio is considered. These grids are predefined and data on the area of fertilized cropland

present in each grid cell in the study domain is available. ArcGIS 10.1 (ArcGIS, ESRI, CA) platform are

used to visualize and analyze spatial information. The baseline year for the model run is 2011. Grid scale

data on soil properties, daily weather, crop areas, N-fertilizer use, cropping and agricultural management

for the 14 weather stations in these 3 states are assembled.

Daily meteorological data files for all the 14 stations are prepared constituting inputs of Julian day,

maximum temperature, minimum temperature, relative humidity, solar radiation and wind speed. Fertilizer

usage files are also prepared for every weather station, with information about the different types of

fertilizers used and their quantities added at different points during a year.

Based on the input parameters of the ecological drivers, DNDC first predicts daily soil temperature,

moisture, Eh, pH and substrate concentration, and then uses the environmental parameters to drive

nitrification, denitrification, methane oxidation/ production, and other relevant geochemical or biochemical

reactions. Daily emissions of NO, N2O, CH4 and NH3 are finally calculated as their daily net fluxes.

This study will help us determine the potential nitrogen emissions in agricultural ecosystems, thus helping

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us integrate the complex interactions among climate, soil, vegetation, soil and biogeochemical processes

in an easy and cost effective way.

Xi Chen

Multifunctional Nanostructured Composite Materials for Highly Active Reductive Catalysis Water

Purification

Multiple nanostructured metal catalysts supported by various materials are produced for reductive

catalysis. Mesoporous materials are regarded as optimal metal catalyst supports due to their highly

ordered pores with controllable sizes and large specific areas, and composite core-shell materials

combining mesoporous shells with non-porous cores (e.g., magnetite nanoparticles that facilitate

separation) are promising materials for environmental applications. In this study, we design and

synthesize a new type nanostructured composite possessing paramagnetic core coated with a

mesoporous silica outer shell containing perpendicular open channels. Nanoparticles of up to six kinds of

hydrogenation metals are loaded at the internal surface of the mesoporous channels. New synthetic

methodologies via particle surface charge tuning are developed to overcome challenges of nanoparticle

aggregation during the synthesis. The materials are characterized with scanning electron microscopy,

transmission electron microscopy, and physisorption and chemisorption analysis. Catalytic kinetics of

these composites reducing a range of aqueous contaminants (e.g., nitrate, chlorate, bromate) are

investigated to evaluate their performance in water purification. We also test the catalysis abilities of

various commercial nanostructured catalysts supported by other different materials, which first gives a

broad evaluation of their catalysis performance, and too provides a comparison for our synthesized

materials. These studies significantly expand the breadth of current nanostructured catalysts and provide

new perspectives for largescale applications.

Aimee M. Gall

Similarities between free chlorine inactivated adenovirus and bacteriophage PR772 inactivation

kinetics and viral replication cycles

With nearly a quarter of the global population consuming fecally contaminated water, waterborne

pathogens can have a significant impact on public health. Human adenovirus (HAdV), is found globally in

water sources and can cause a variety of illnesses including gastroenteritis, respiratory disease, and

conjunctivitis. HAdV is of particular concern in drinking water because of its resistance to common

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disinfectants such as low-pressure ultraviolet light and monochloramine. The reason HAdV is so resistant

to monochloramine yet so susceptible to free chlorine remains unknown. We developed a quantitative

assay to analyze the HAdV serotype 2 (HAdV-2) replication cycle. HAdV inactivated up to 99.99% by free

chlorine still attaches to host cell monolayers, but genome synthesis as well as late hexon mRNA and

early E1A mRNA transcription are inhibited. Additionally, we have been studying bacteriophage PR772 as

a potential surrogate for HAdV-2 because of morphological and replication similarities. When exposed to

free chlorine, we have shown that PR772 has remarkably similar inactivation kinetics compared to HAdV-

2. We developed a parallel quantitative assay and observed free chlorine inactivated PR772 can still

attach to host cells and has the same inhibition of genomic replication and mRNA transcription as HAdV-

2. A more fundamental understanding of how viruses become inactivated is key for the development of

new disinfection technologies and sensors to detect infectious viruses.

Nolan Fan

Hydraulic Fracturing

Currently, the most prevalent disposal method is deep well injection, during which produced water is

pumped into porous areas between impermeable layers of rock. This solution is becoming unfavorable as

transportation costs continue to rise, regulatory agencies continue to implement more strict regulations,

and the capacity of injection wells are reaching maximum levels.

Big companies should invest in designing and implementing on-site treatment systems including

technologies such as membrane filtration and water softeners. The benefits of such an investment include

recycling of wastewater for future fracking operations, reduced waste stream, reduced fresh water

procurement costs, reduced transportation costs, and improved relations with surrounding community.

Meredith Cote

Effects of anthropogenic influences on the Maple River using a biotic index and water chemistry

analysis

Aquatic systems play an integral role in wide ranging ecological contexts by providing an outlet of nutrient

and chemical buildup. Rivers are particularly vulnerable to deleterious anthropogenic effects given their

popularity as transit and recreation waterways. The health of a stream can accurately be assessed using

an index of macroinvertebrate diversity as well as chemical concentration tests. Our study found that the

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Maple River shows few negative effects of anthropogenic structures on macroinvertebrate health and on

overall stream health. The presence of a wetland may also have served to mitigate the effects of

manmade structures on overall stream health.

Ariel Carmichael

Bacterial Adhesion and Detachment from Model Mineralized Biofilms

Pathogen outbreak has been linked to drinking water distribution systems (DWDS), where they have

been found to be harbored in layers inaccessible to disinfectants. Biofilm growth is ubiquitous in natural

and engineered environments, including the pipe networks of DWDSs. In addition to biofilms, calcium

carbonate is also often found precipitated on pipe walls and biofilms but its role on the interaction

between the biominerals and the pathogens is still unknown. The objective of this study is to determine

the influence of calcium carbonate precipitate on pathogen adhesion to biofilms and detachment from

biofilms. Thus far, the research focus has been to create a gel with similar elastic moduli as real biofilms

to perform systematic studies of calcium carbonate precipitation within the gel and the change of gel

properties. Experiments have mainly focused on agarose, a polymer made of chains of alternating

galactose and anhydrous galactose, whose elastic modulus can be tuned by varying the agarose content

(Normand et al. 2000). Thermogravimetric Analyses (TGA), differential scanning calorimetry (DSC), and

Fourier transform infrared spectroscopy (FTIR) have been used to elucidate gel composition and

response to mineral precipitation, including the cross-linking of the polymers. The future work will focus

on the extension of these studies to real biomineralized biofilms and to measurements of adhesion

between model biofilms and colloidal particles as a function of the mineral content.

Marta Grabowski

Assessing the Environmental Impacts and Costs Associated With Construction of Roadway

Drainage Systems

Transportation systems today are moving towards sustainable design solutions in an effort to minimize

negative environmental impacts. This research focuses on the materials and construction/maintenance

phases of roadway drainage systems. By diverting water away from driving surfaces, drainage systems

are crucial to a safely functioning roadway. Roadway drainage systems typically include one or more of

the following components: Ditches, Bioswales, Culverts, Detention Basins, Pipe Underdrains, and Storm

Sewers. The selection of individual components and their detailed design is highly standardized, with little

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or no understanding of the broader environmental and economic implications of such decisions. In

particular, broader environmental implications of drainage components can be characterized by Life Cycle

Assessment (LCA), a valuable tool that quantifies cradle-to-grave environmental impacts of an

engineered system. By coupling LCA with cost analysis, trade-offs from design decisions across

dimensions of sustainability provide a more robust assessment of roadway drainage systems.

Understanding the consequences of materials and construction alternatives will allow the transportation

industry to make well-informed design decisions and identify opportunities to advance multiple

dimensions of sustainability.

Amanda Lardizabal

Elucidation of key microalgal bioprocess design parameters on extant and intrinsic kinetic

parameters

Algal removal of nitrogen and phosphorous from wastewater is an advantageous way to prevent the

increasing problem of eutrophication and harvest algal biomass for bioenergy. Wastewater contains an

ample supply of nutrients, such as carbon, nitrogen (N), and phosphorous (P), essential to algae growth.

Therefore, as algae uptake nutrients into the cell for growth, they are concurrently achieving objectives for

wastewater treatment: N and P removal from the wastewater. Current wastewater treatment processes

using algae are not energy-positive and do not consistently remove nitrogen (including dissolved organic

nitrogen) below the current limit of technology (~ 1-3 mg-N/L). The objectives of this research are to

conduct experiments with mixed algal communities to elucidate how key bioprocess design parameters

influence extant and intrinsic kinetic parameters, as well as microalgal metabolism and the bioprocess as

a whole. These parameters will be measured in batch studies by removing biomass from a steady-state

photobioreactor (PBR) and distributing it evenly between replicate flat panel batch PBRs. Each PBR will

be exposed to the same light, pH control, air sparging, and nutrients. Samples will be taken continuously

throughout the study to monitor N and P uptake, carbohydrate and lipid storage rate and capacity, optical

density, cell concentration, and protein content. The analyzed results will then be utilized to optimize the

design of small-scale PBRs for kinetic studies with microalgae.

Lauren Valentino

Covalent organic frameworks for water purification applications

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The increasing global demand for safe drinking water and environmental concerns about current

treatment methods have inspired research and development of novel water treatment approaches.

Membrane technologies are particularly attractive because they provide a physical barrier to water

contaminants and require no chemical additives or thermal input. Asymmetric membranes with a dense

active layer supported by a thicker, highly porous substructure offer good selectivity to remove a range of

water contaminants, high water permeability, and mechanical strength. However, in spite of its

advantages, a more widespread application of membrane technology in water treatment is limited due to

the high cost of energy and membrane operational problems associated with fouling and fouling control

strategies.

As an alternative to conventional polymeric membrane materials, covalent organic frameworks are an

emerging class of crystalline, porous organic materials, which are constructed by joining organic building

units via strong covalent bonds. Their high degree of crystallinity, in combination with the permanent and

regular pore structure, allows for the creation of one-dimensional channels that are ideal for separation

processes. The applicability and use of a covalent organic framework will be discussed.

Josue Lopez

Bio-Inspired Study on Calcium Carbonate Crystallization

Calcium Carbonate is ubiquitous in many natural systems and industrial processes. It can be found as

one of five crystalline polymorphs or as an amorphous phase, and can precipitate in both, anhydrous and

aqueous environments. While industrial processes are negatively affected by the precipitation of Calcium

Carbonate, many organisms use Calcium Carbonate as the main shell component for protection or

calcium storage. The organic molecules present in these organisms can template Calcium Carbonate and

exhibit exquisite control on the final morphology of the biomineral that forms. These complex pathways to

biomineralization are not yet fully understood. Better understanding of these mechanisms is needed for

the development of sustainable biomimetic materials.

The nucleation and surface-deposition of Calcium Carbonate is being studied with a Transmission

Interferometric Adsorption Sensor (TINaS). This technique employs a light source and a multi-layer

sensor to generate well-characterized interference patterns. Adsorbed mass on the sensor’s surface can

be detected by changes in interference patterns. A variety of organic macromolecules can be adsorbed

on the TINaS sensor to mimic templated nucleation, as observed in nature. Preliminary results show that

the formation and surface-deposition of Calcium Carbonate can be detected with this technique in real

time. Our results also show that the organic template (PEI) can favor the formation of specific crystalline

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polymorphs.

These experimental efforts are complemented with quantum chemistry simulations. Computational

chemistry simulations can provide valuable insights of the system at the molecular scale. Preliminary

studies of Calcium Carbonate in aqueous systems have been performed to understand the behavior of

fully-solvated molecules. The first hydration shell of Calcium Carbonate has been determined rigorously

using a combination of numerous computational platforms. Our future simulations will include organic

additives to evaluate their influence on nucleation.

Hou In Cheong

Metastable calcium carbonate precipitates with organic additives

Calcium carbonate has been an interest in the study of biomineralization because of the discoveries of its

critical role in morphological control of biominerals, among others. Therefore, it becomes desired to obtain

a comprehensive understanding of the behavior and properties of organic calcium carbonate. In this work,

we are trying to elucidate the influence of organic additives in solution on the precipitation path of calcium

carbonate minerals and are especially interested on metastable phases that are stabilized by the organic

components.

Mixtures of sodium carbonate and calcium chloride solutions are done in a 1:1 stoichiometric solution at

various ionic strengths and pH-conditions, with the presence of selected amino acids, whose

concentrations will vary. The dry calcium carbonate precipitate is analyzed by Thermogravimetry,

Differential Scanning Calorimetry, and Fourier Transform Infrared Spectroscopy. The composition and

properties of the precipitates is obtained from the thermal decomposition of the organic calcium

carbonate, the heat flow produced during phase transformations of minerals, and the infrared light

adsorption as a function of wavelength. Complementary investigations are obtained by Scanning Electron

Microscopy and XRD. The analysis of these measurements will help to understand how amorphous

calcium carbonate can be stabilized by organic/inorganic interactions.

John Witter

Feasibility of of small-scale wind turbines for residential energy use in Champaign-Urbana

Analyzing the energy availability of micro wind turbines in an urban environment compared to the typical

electricity demand of an apartment of small house. Further analysis on any limitations to implementation

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as well as environmental impacts of switching from traditional energy sources to renewable. If I have

enough time and resources I might look at the possibility of connecting to the grid, cost analysis, or ability

to store power in batteries.

Nikhil Rao Susarla

Life Cycle Analysis of Perchlorate Treatment using Bio-catalysts.

Perchlorates are extremely harmful chemicals present in eco-systems. They are both naturally occurring

and man-made used in production of various chemicals. They can also be present in some fertilizers and

bleach. They cause growth problems by disrupting hormonal functions in the thyroid. Existing methods for

perchlorate removal are hampered by the co-occurrence of Nitrate which is similar structurally and also a

more preferred electron acceptor. Enzymes present in certain microorganisms (Perchlorate Reductase

and Chlorite Dismutase) have been shown to have a high efficiency of perchlorate removal and more

importantly have a similar efficiency even in the presence of Nitrate. To ensure that this is a safe

technology to use, a Life Cycle Analysis (LCA) is conducted to assess the total impact of the entire

process from cradle to grave.

Xia Shang

Effects of poly(3,4-ethylenedioxythiophene) in asymmetric carbon electrodes for capacitive

deionization

The performance of a capacitive deionization (CDI) system consisting of conventional film electrodes is

limited by the insulating properties of predominantly used fluorinated polymeric binders. Poly(3,4-

ethylenedioxythiophene) (PEDOT) based material is known as one of the most important conductive

polymers with high electrical conductivity, pseudocpacitance, and chemical stability. In this study,

commercial PEDOT:PSS is coated on activated carbon particles and post-treated with a co-solvent

solution. The effects of PEDOT enhanced ionic and electronic mobility on salt removal and

electrochemical performance are investigated when different aqueous counter ions are used in the

electrochemical polymerization process. Moreover, the composition, morphology, and salt incorporation

mechanism are characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy,

and Fourier transform infrared spectroscopy. After characterization, asymmetric CDI systems are

assembled with selected cathode material and the salt removal rate and overall energy efficiency are

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compared. This study provides in-depth understanding of the pseudocpacitance behavior of PEDOT in

CDI and the incorporation of different counterions in the tailored CDI electrodes.

Yijue Diao

Calcite Surface Interctions in Aqueous Solution investigated by Colloidal Probe Atomic Force

Microscopy

The formation of minerals mediated by living organisms is called biomineralization. The presence of

organic templates and organic solutes provides unique structural contributions, resulting in unique

chemical and mechanical material properties. Such a process spanning both organic and inorganic world,

requires interdisciplinary research efforts. Studies on the mechanisms of biomineralization will enable us

produce innovative materials with specific properties, which will bring about a more sustainable

environment. Among miscellaneous minerals, calcium carbonate is the most common species. The

interfacial properties of calcium carbonate in aqueous system have not been fully understood yet. In this

study, direct force measurements are conducted on a calcite substrate in water and saturated calcium

carbonate solution by Colloidal Probe Atomic Force Microscopy (AFM) in contact mode.

The classical theory for double layer interactions cannot be applied for divalent ions in aqueous solution

between dissimilar surfaces. The Poisson-Boltzmann (PB) equation is applied to describe the

electrostatic potential and to help understand surface properties of calcite. We expect to identify changes

of the surface properties of calcium carbonate during crystallization and dissolution through time-

dependent force measurements. At surface separations smaller than 5 nm a hydration force is observed

as a repulsion with superposed steps that result from the squeezing out of surface-adsorbed layers of

ions and water (as shown in Figure 1). In future work organic additives will be introduced in the system,

These studies will help elucidate the critical interaction underlying biomineralization.

The formation of minerals mediated by living organisms is called biomineralization. The presence of

organic templates and organic solutes provides unique structural contributions, resulting in unique

chemical and mechanical material properties. Such a process spanning both organic and inorganic world,

requires interdisciplinary research efforts. Studies on the mechanisms of biomineralization will enable us

produce innovative materials with specific properties, which will bring about a more sustainable

environment. Among miscellaneous minerals, calcium carbonate is the most common species. The

interfacial properties of calcium carbonate in aqueous system have not been fully understood yet. In this

study, direct force measurements are conducted on a calcite substrate in water and saturated calcium

carbonate solution by Colloidal Probe Atomic Force Microscopy (AFM) in contact mode.

The classical theory for double layer interactions cannot be applied for divalent ions in aqueous solution

21

between dissimilar surfaces. The Poisson-Boltzmann (PB) equation is applied to describe the

electrostatic potential and to help understand surface properties of calcite. We expect to identify changes

of the surface properties of calcium carbonate during crystallization and dissolution through time-

dependent force measurements. At surface separations smaller than 5 nm a hydration force is observed

as a repulsion with superposed steps that result from the squeezing out of surface-adsorbed layers of

ions and water. In future work organic additives will be introduced in the system, These studies will help

elucidate the critical interaction underlying biomineralization.

Alexis Sheehan

Effects of Nanoscale Roughness on Ionic Liquid Surface Behavior - Smart Interfaces for

Environmental Nanotechnology

As the demand for renewable energy increases, so does the need for safe and efficient large-scale

energy storage and delivery systems that can function under varying loads and a wide array of

temperatures. Supercapacitors, also known as EDLCs (electrical double layer capacitors), have this

flexibility while providing higher energy storage than traditional capacitors and greater power output than

batteries. My research aims to increase the viability of supercapacitors for storage and distribution of

renewable energy through the use of ionic liquids an electrolyte replacement.

Ionic liquids exhibit high charge densities, low volatilities, low flammability and large electrochemical

windows while remaining largely chemical inert, which make them good candidates for electrolyte

replacements. However, many of the processes that dictate the formation of electrical double layers, as

well as fundamental interactions with the electrode surface are mostly unknown. This hinders the ability to

design efficient electrochemical cells using ionic liquids. Much of the research being completed focuses

on ionic liquid interactions with smooth surface such as graphene. However, a true electrochemical cell

uses rough carbon-based surfaces.

I will focus on modifying a smooth surface, silicon, into a surface with a well-defined roughness. This is

completed using poly(ethyleneimine), PEI, to charge the surface of the silicon. Then adsorbing silica

nanoparticles onto the PEI. Finally the silica nanoparticles are sintered to silicon wafers. This will create a

surface with a known nanoscale roughness.

In the coming months, ionic liquids will be placed in droplets on smooth and rough silica. Using atomic

force microscope (AFM) force curves and friction measurements will be taken. These AFM

measurements will be used to characterize changes in surface-ionic liquid interactions, thickness and

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composition of the double layer caused by the well-defined roughness. Future work will consist of laying

graphene over the roughed silicon to create graphene with a known roughness and completing force

curves and friction measurements to better understand the effect of roughness on ionic liquid functionality

in electrochemical cells.

Laura Southworth

Understanding organic fouling in membrane capacitive deionization systems to enhance water

reclamation sustainability

Membrane capacitive deionization (MCDI) systems have the potential to lower the energetic demand of

freshwater production from unconventional sources like brackish water and reclaimed wastewater through

direct treatment or by treating brine generated by existing pressure-driven systems like reverse osmosis

(RO). Organic fouling at filtration interfaces significantly increases energy consumption and adversely

impacts freshwater production rates by obstructing water flux through the membrane. While RO fouling

has been well characterized, little is known about the impact of organic foulants on ion adsorption in

MCDI systems. In these systems, fouling layers could accumulate on the ion exchange membrane or the

electrode itself, impeding flux and adsorption of ions out of bulk solution and onto the charged electrodes.

Electrode potential could also impact foulant accumulation, producing fouling mechanisms distinct from

those of RO fouling. Synthetic saline solutions containing model organic foulants will be used to evaluate

MCDI fouling potential. Feed solutions will run through a lab-scale MCDI system, and the extent of fouling

and scaling will be evaluated by observed changes in desalination performance and flow path pressure

drops. Scanning electron microscopy and energy-dispersive X-ray spectroscopy will be used to

characterize the electrode structure before and after fouling to evaluate the extent of structural changes.

Atomic force microscopy (AFM) will be used to measure the interaction forces between a charged

colloidal AFM tip and polarized electrodes under different set potentials and solution conditions. Several

cleaning solutions will be tested on the fouled membranes, and the extent of recovery of initial

desalination performance, flow path pressure drops and structure will be measured.

Yew Chin Raymond, Choo

Surface force apparatus in environmental science

Many processes in environmental engineering are driven by surface phenomena as they involve bodies

of micro scale dimensions. For example, in water treatment, surface interactions are responsible for initial

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flocculation and coagulation of small colloids to form larger particles that can be effectively removed by

sedimentation. Activated carbon, used for the adsorption of contaminants, is widely adopted because of

its large surface area to mass ratio. The fouling of membranes, a pertinent problem with membrane

filtration, is largely attributed to undesirable surface properties that favour foulant attachment. The study

of surface science enables a better understanding of the fundamental mechanisms behind these

processes.

The surface force apparatus (SFA) is an instrument that directly measures surface forces. Over the past

50 years, SFA measurements have provided insights into the nature of electrostatic surface, Lifshitz/van

der Waals and solvation/hydration forces. The power of the SFA comes from its ability to measure forces

at sub molecular separation distances. This precise determination of separation distance is achieved

utilizing white light interferometry while force measurement is determined by a spring connected to a

cantilever. In contrast to the atomic force microscopy (AFM) technique, the absolute separation distance

measured from interferometry is used to calculate the force magnitude in the SFA. This precise

determination of separation distance is one of its advantages. Another advantage is lower stresses due to

a larger contact area.

The Smart Interfaces in Environmental Nanotechnology group is home to the eSFA-II. The instrument

features automated real time spectrum correlation for separation distance measurement. Housed in a

thermally insulated box and anti-vibration table, the combined thermal and mechanical drift is as low as

20pm/min with resolution of 15pm. Upcoming experiments with the instrument aim to investigate

molecular ordering of ionic fluids in confinement and interaction between graphene surfaces intercalated

by a fluid layer.

Yuting Chen

Thermal Stability Study of Ionic Liquids

21st Annual UIUC EES Spring SymposiumThermal Stability Study of Ionic Liquids

Yuting Chen, Andres Jurado, Rosa M. Espinosa-Marzal,

Civil and Environmental Engineering, University of Illinois at Urbana-Champaign

Abstract

Room temperature ionic liquids are organic moleten salts that are liquid below 100 °C. Nowadays, Ionic

liquids (ILs) are receiving more and more attention due to many practical applications, especially in the

field of renewable energy as electrolytes for supercapacitors, solar cells, fuel cells, or heat transfer fluid.

In order to better understand the performance of ILs in various conditions, the thermal stability of the ILs

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must be evaluated. The Differential Scanning Calorimetry (DSC) is used to determine the temperature at

which phase change (crystallization/ glass transition/ melting) happens and the involved heat of

transformation. In this work, the thermal stability of Emim-EtSO4 (EE), Hmim-EtSO4 (HE), and Hmim-Ntf2

(HN) were studied. The temperature was ranged between -75ºC to 100 ºC, with a scanning rate of 10 ºC

and 2 ºC per minute, respectively. The results for EE were in agreement with previously reported results.

The HN data showed a pronounced melting peak at a temperature of -7 ºC and a crystallization peak at -

33 ºC, which were also consistent with published data. Moreover, a small melting peak was observed at -

0.9 ºC, which is likely by the melting of residual water (~0.2 wt%) in HN, suggesting the presence of water

clusters in HN. On the other hand, the HE samples were tested after storage in the DSC pans for different

periods of time. For HE a broad melting peak was observed after 18 days, which indicates the change of

the nanostructure (freezing) with time. The results also suggested that moisture may play a significant

role on the thermal properties of the ILs. Therefore, we will investigate the influence of water content on

the thermal stability of the ILs in a systematic way in our next experiments.

Zhuojun Yu

China’s climate-change policy to address Climate Change

In order to address the global environmental issue, China has signed Kyoto Protocol on May 29th, 1998,

and ratified it on September 3rd, 2002, and formed the Asia-Pacific Partnership (APP) on Clean

Development and Climate with Australia, India, Japan, Korea and the United States. In demotic policy, for

drawing up a plan under the Kyoto Protocol after 2012, the State Council of China officially issued its

"Twelfth five-year" control scheme for greenhouse gas emissions in December 2011. This scheme made

an overall arrangement for controlling the greenhouse gases emissions and clearly defined the

greenhouse gases emission target from 2011 to 2015.

Xiangchen Huo

Catalytic reduction of nitrate and nitrite in solution by Ru catalysts

The performance of supported Ru catalysts on catalyzing nitrate and nitrite reduction by hydrogen was

investigated. Ru showed high activity of nitrate reduction but low activity of nitrite reduction. When Ru was

employed alone, ammonium dominated the product of nitrate reduction, and was not influenced by initial

nitrate concentration. In contrast, selectivity of ammonium during nitrite reduction decreased with

increasing initial concentration of nitrite. Neither physical mix of Pd with Ru nor deposition of Pd on

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carbon supported Ru affected nitrate reduction activity or product selectivity, raising the question whether

nitrite is an intermediate from nitrate reduction. Ru is a potential alternative for catalytic nitrate reduction

in terms of competitive cost, high activity, and applicability in a wide range of solution pH. But effort is

needed to improve its product selectivity.

Hanting Wang

Quantification of rotavirus removal in biosand filters using an integrated cell culture and reverse

transcription quantitative PCR assay

Diarrheal diseases caused by pathogens remain a constant threat to millions of people around the world

who lack access to safe or improved drinking water sources. Recent studies on biosand filters, a

commonly used point-of-use technology for treating drinking water, have shown that bacteria and

bacteriophage removal can reach USEPA and WHO standards. However, the efficiency of human enteric

virus removal in biosand filters has not been studied. Rotavirus was used in this study because it is the

leading cause of diarrhea in children under the age of 5 around the world. Two scaled down PVC biosand

filters with 55 cm sand depths were used to determine the efficacy of rotavirus removal as a function of

depth, residence time, and flow rate. One filter was fully ripened and the other was unripened at the start

of the experiments to compare rotavirus removal at different media aging periods. An integrated cell

culture and RT-qPCR assay was developed to quantify rotavirus removal in water samples collected from

the filters. Preliminary results show that the assay is more sensitive and has a lower detection limit (10^-2

FFU/mL) compared to the standard rotavirus infectivity test (10^2 FFU/mL) or RT-qPCR (10^1 FFU/mL)

alone. This is the first study to determine the efficiency of rotavirus removal in biosand filters, which is an

essential first step in understanding the extent to which biosand filters can remove human enteric viruses,

and hence reduce diarrheal disease incidences.

Heather Gipp

Phytoremediation of Lead using Urban Trees

Lead pollution is very prevalent in urban areas due to industrial processes and commercial products. In

an urban environment, using arborous species for phytoremediation would be a sustainable option for

long-term remediation. However, arborous species are typically less efficient in accumulation. With

application techniques such as EDTA and biochar soil amendments, there is a possibility that lead

accumulation by trees could be enhanced. This project, which took place at the Morton Arboretum in

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2013, studied the lead phytoremediation capabilities of Salix alba and Platanus x acerifolia, two common

urban trees that have shown phytoremediation capabilities. The experiment was conducted in a

greenhouse setting with soil microcosms and studied the effects of EDTA and biochar additions on lead

accumulation by urban trees. After harvesting the trees and collecting the soil, plant biomass and soil

samples were digested and lead levels were analyzed on the atomic absorption spectrometer. Results

showed that the Salix alba had a much higher biomass than Platanus x acerifolia. However, the Platanus

x acerifolia had a much higher mg Pb in biomass/kg Pb in soil, so the uptake of lead by Platanus x

acerifolia could have inhibited its growth. Biochar application did not show a strong increase in lead

accumulation. The effect of EDTA on the plants showed an increase in lead uptake, but a decrease in

plant growth.

Abiodun Oki

Novel tailor-made dendrimer based nanofiltration membranes

In this work, we describe how novel membranes which are at the boundary of ultrafiltration and

nanofiltration can be developed using novel tailor-made dendrimer based materials that can be tuned and

functionalized as the active layer of the membrane. We achieve this via an interplay of organic synthesis,

material characterization and physics of separation to develop membranes that can reject both small

colloidal and dissolved organic matter while at the same time selectively allow the passage of inorganic

ions, yet possess resistance to fouling and chemical degradation. In this way, we intend to make progress

in fundamentally understanding the mechanisms involved in the surface and transport interactions of

water, dissolved organic matter and ions during membrane separation, hence enabling further advances

in the development of new membrane materials in the future.

Andrew J. Nelson

Measurement of Ammonia Exchange above a Fertilized Maize Canopy

Use of nitrogenous fertilizers for agricultural crop production contributes more than 50% of total

anthropogenic ammonia (NH3) emissions in Illinois. NH3 emission results in the formation of small

diameter (≤2.5µm) particulate matter; (PM2.5), that have adverse effects on health and visibility and can

modify the radiative balance of the Earth . The emission of gaseous NH3 from agricultural cropland is not

well characterized, having been experimentally quantified for a limited number of crop types and

locations. This research seeks to improve the understanding of NH3 emission above a maize canopy in

central Illinois.

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A relaxed eddy accumulation (REA) system was designed, deployed, and operated above a fertilized

maize canopy at the University of Illinois at Urbana-Champaign (UIUC) Energy Biosciences Institute (EBI)

Energy Farm in Urbana, IL during the 2014 growing season. Average NH3 flux and concentration was

measured throughout the growing season, focusing particularly on the first four weeks after fertilization.

Maximum NH3 concentration (8.11 µg/m3) was observed during the period nearest fertilization. Similarly,

maximum positive NH3 flux (transport away from the surface) was observed in the three-week period

following fertilization (430.2 ±347.0 ng/m2/s) with lower positive flux observed for the remainder of the

season (31.7 ±104.5 ng/m2/s).

Kan Fu

A case study of Weather Research and Forecasting model over Midwest USA

Air pollutants, such as particulate matter and ozone, continue to cause environmental problems and

threaten humans’ health, and it is essential to understand how they are formed, transported and removed

from the atmosphere before control strategies are implemented. Chemical Transport Models (CTMs) can

be useful tools to estimate concentrations of these pollutants given emission intensities of primary

pollutants and meteorological conditions, thus supporting policy making. A good prediction of CTMs relies

heavily on accurate meteorological data as inputs. The Weather Research and Forecasting (WRF) model

is a numerical weather prediction model that is commonly used to provide input to CTMs. The WRF

model includes a number of domain configurations and parameterizations to accommodate various

spatial resolutions and regional characteristics. Therefore, before the WRF output is used as input to a

CTM, the most appropriate parameterization needs to be identified.

WRF simulations were conducted over Midwest USA for May 2011. The WRF output will be used to

process gridded emissions and as input to a CTM with the intention to study effects of reactive nitrogen

emissions to the atmosphere from intensive fertilizer usage on air pollutant formation, transport and

deposition. Meteorological station measurements of wind speed, wind direction, temperature, precipitation

and relative humidity were used to evaluate the WRF output. The WRF output was optimized by

considering the nesting method, input dataset choice, and grid spacing. Sensitivity analysis was done to

optimize the combination of WRF physics options in microphysics, land surface model, planetary

boundary layer, radiation and cumulus cloud parameterizations.

Michael Cunningham

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Impact to Water Quality from Hydraulic Fracturing

Gas well drilling has grown exponentially since 2008 after advances in drilling technologies allowed the

capture of natural gas and oil reserves from shale and tight sand formations. Hydraulic fracturing uses

large volumes of high-pressured water and a mixture of toxic organic and inorganic chemicals to obtain

these reserves. My goal will be to explore the pathways for drinking water contamination from fracking

sites, and research the water treatment options available to decrease the risk of exposure to the

surrounding environment.

Yichen He

Modeling Interactions between Cells and the Aqueous Environment

Nanoparticles, heavy metals and ions generated from industry that are released to the aqueous

environment, may react with microorganisms and be toxic to them. The main goal of this research is to

investigate the interactions between model cells and the aqueous environment. In this work, the model

cell membrane consists of a polymer-supported lipid-bilayer, specifically, a polyacrylamide hydrogel, and

supported Eggphosphatidycholine (EggPC). Hydrogels are cross-linked polymer networks that can

absorb large amounts of water, and are very compliant. Both, (neutral) polyacrylamide, and (negatively

charged) acrylamide-co-itaconic acid hydrogels were characterized in swelling/collapsing experiments;

the adsorption kinetics of bovine serum albumin (BSA) and ε-polylysine under controlled conditions of pH

and ionic strength was determined by a Transmission Interferometry Adsorption Sensor. The results show

that the adsorption of both BSA and ε-PLL by charged hydrogels is much stronger than by neutral

hydrogels. Furthermore, strong absorption into the gel pores is observed in both of them. These

measurements suggest that both, i) electrostatic interactions , and ii) the different network structure

provided by the itaconic acid, may influence adsorption and absorption. Accurate interpretation of these

data requires precise knowledge of the hydrogel mechanical properties. Thus, nanoindentation of both

neutral and charged hydrogels using atomic force microscopy (AFM) is used to study the mechanical

behavior. A spherical indenter with 5-µm radius was used in the experiments and all indentations were

done with the hydrogel completely immersed in water. Polyacrylamide gels were tested under different

loading rates and the Herz equation was used to model the results. The results show an increase of

hydrogel Young’s Modulus with loading rate, which is characteristic of viscoelastic response. In the last

part of this work, the influence of the lipid bilayer on both, adsorption and mechanical properties will be

investigated. The long-term goal of this project is to establish an experimental platform that can be used

to investigate cytotoxicity.

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Laura Fierce

Quantifying the impact of particle composition on light absorption by black carbon

absorption. For example, if particles in BC populations were assumed to have uniform composition,

similar to the representation applied in modal models, absorption enhancement was overestimated by as

much as a factor of two relative to more realistic treatments of particle composition. By applying realistic

distributions of particle composition from a particle-resolved aerosol model, we found weak absorption

enhancement at low relative humidity (Eabs = 1±1.3), consistent with ambient observations that are

performed at low relative humidity. On the other hand, we found strong absorption enhancement (Eabs >

1.8) in many locations if particles were modeled using the global variation in relative humidity.

Bernardo Vazquez Bravo

Inactivation of Adenovirus with Filtered Polychromatic Medium-Pressure Ultraviolet Light

Ultraviolet (UV) light is a drinking water treatment technology that has been gaining popularity due to

increased concern about disinfection by-product formation when chlorine is used as disinfectant. UV light

does not produce by-products at the doses commonly used in the water treatment industry. There are

different sources of UV light that are commercially available but the most commonly used are

monochromatic low-pressure (LP) and polychromatic medium-pressure (MP) UV lamps. Human

adenovirus, a double stranded DNA virus, has been recognized as the waterborne pathogen with the

highest resistance to UV light inactivation. In this study the inactivation of adenovirus 2 was assessed by

plaque assay and combined with molecular techniques such as RTqPCR, and Long-Range (LR)PCR to

elucidate at which step of the viral infection cycle adenovirus is getting inhibited. Specific wavelengths

within the germicidal range (200-300 nm) were isolated from a MP lamp source using band-pass filters

and evaluated to assess different steps of the virus infection and target components of the virion. The

findings of this work will help to better understand the mechanism by which UV light inactivates viral

pathogens and which component of the virus is being damaged during disinfection.

Andrea Vozar

Characterization of protein adsorption on polyamide water filtration membranes

Nanofiltration (NF) and reverse osmosis (RO) membranes are barrier-based water treatment technologies

able to provide rejection of all pathogens and most organics, emerging contaminants, and multivalent

30

ions. RO membranes also reject monovalent salts. Polyamide is a state-of-the-art NF and RO active

layer material and is highly susceptible to fouling, or the build up of unwanted organic compounds on a

membrane surface. 30% of the energy consumption in current polyamide membrane applications is

attributed to fouling. Polyamide is not used presently with high organic content waters, such as

wastewater or during seawater algal blooms.

There are three forces acting at the membrane-feed solution interface: adsorptive molecular forces,

pressure, and shear. The adsorption of a surrogate protein onto four commercial NF and RO membranes

with different pores size, active layer thickness, roughness, and surface coatings are compared. Batch

adsorption experiments are performed to determine the effect of pH on (1) protein adsorption and (2)

protein adsorption when divalent cations are present. Membrane active layer and fouling layer surface

properties are measured using microscopy techniques. Distinguishing between the polyamide and the

protein is challenging as both are composed of the same elements: hydrogen, carbon, oxygen and

nitrogen. The protein is modified with a known quantity of halogen to differentiate them. Rutherford

backscattering spectrometry (RBS) shows protein adsorption decreases to zero with increasing pH.

Membranes with more terminal amine groups have higher protein adsorption, indicating the protein

adsorbs to polyamide protonated amines. In the presence of a divalent ion, protein adsorption varies

similarly to the protein only adsorption below the pKa of the membrane carboxylic group. Above the

membrane carboxylic group pKa, protein adsorption is higher and never zero when divalent ions are

present. It is hypothesized because of the presence of the protein at high pH that divalent ion bridging

occurs between the deprotonated carboxylic acid on the membrane surface and a negatively charged

group on the protein.

Erin Bak

Antibacterial Calcium Carbonate

The objective of this project is to synthesize biodegradable micro- and nanoparticles based on calcium

carbonate to be used for water treatment purposes. Polycationic natural and synthetic polymers have

been shown to interact electrostatically with bacteria and kill them. Thus, single calcite crystals and the

mineral particles are coated with selected polyelectrolytes. The adsorbed mass of polyelectrolytes on the

mineral is measured with a Quartz Crystal Microbalance and interferometry. Atomic Force Microscopy

(AFM) is used to measure the interaction forces between the coated mineral particles as well as the long-

term resistance of the polymers grafted to the mineral. Our measurements indicate that the polymers

stabilize the particles in solution.

31

The outlook of this project is to prove the antibacterial action of the coated mineral particles and the rate

of dissolution under various environmental conditions. For this purpose we plan to combine AFM with

fluorescence microscopy, among other techniques. Escherichia coli (E. coli), a rod-shaped member of the

coliform group, has been chosen for these future studies.

Sital Uprety

Effects of climate-induced changes in water quality and risk of diarrheal diseases in Nepal and

Uganda

Poor water quality and limited sanitation is resulting in estimated 3.5 billion diarrheal episodes and

causing 1.87 million childhood deaths per year world from diarrhea, mostly in developing world. Climate

change is likely to have wide range of health effects on these communities in that lack adequate water

and sanitation infrastructure. The study proposes that drastic change in hydroclimatic process such as

extreme drought and precipitation in Uganda and Nepal leads to differences in microbiomes of water due

to changes in gut microbiomes of individuals and subsequent outbreaks of pathogens. The study will

monitor several cycles of drought and wet seasons in Nepal and Uganda and will be investigated for

abundance and distribution of diarrhea-causing pathogens and other microbes using metagenomics. The

results of metagenomics will guide microfluidic quantitative PCR which will allow comprehensive and

simultaneous determination of all diarrhea causing pathogens. This information can be used to modify the

existing drinking water system to consider climate change as a factor and also can be used to create a

model to predict the outbreak of diarrheal diseases in the future.

Ian Bradley

Selection of lipid and carbohydrate accumulators for enhanced algal feedstock production and

nutrient recovery from wastewater

Algae are one of the most promising bioenergy feedstocks of the 21st century. Productivity of converting

CO2 to carbon rich lipids for biodiesel is nearly 10x greater than the most efficient traditional crop, oil

palm, and over 130x and 340x more productive than soybean and corn, respectively. However,

production of biofuels from algae is still prohibitively expensive. Coupling algae production with

wastewater treatment can offset the high energy and nutrient demands that make algal biofuels so costly.

Currently, there is a fundamental lack of understanding concerning the impact that real-world

environmental factors (e.g. light intensity, operating parameters, competition between organisms) have on

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algae growth in wastewater and production of carbon storage compounds such as lipids and

carbohydrates. Understanding and predicting the rate at which these storage compounds are produced

and degraded is critical to the design of efficient processes for algal growth. Preliminary work using pure

culture Chlamydomonas reinhardtii has been performed to better understand the effects that nitrogen and

phosphorous starvation have on increasing organic carbon storage. Additionally, mixed community

growth on high strength wastewater has been demonstrated. This presentation will discuss the results,

along with methods and proposed work aimed at selecting for specific carbon storage compounds within

mixed wastewater communities for improved algal feedstocks.

Andrea Vozar

Characterization of protein adsorption on polyamide water filtration membranes

Nanofiltration (NF) and reverse osmosis (RO) membranes are barrier-based water treatment technologies

able to provide rejection of all pathogens and most organics, emerging contaminants, and multivalent

ions. RO membranes also reject monovalent salts. Polyamide is a state-of-the-art NF and RO active

layer material and is highly susceptible to fouling, or the build up of unwanted organic compounds on a

membrane surface. 30% of the energy consumption in current polyamide membrane applications is

attributed to fouling. Polyamide is not used presently with high organic content waters, such as

wastewater or during seawater algal blooms.

There are three forces acting at the membrane-feed solution interface: adsorptive molecular forces,

pressure, and shear. The adsorption of a surrogate protein onto four commercial NF and RO membranes

with different pores size, active layer thickness, roughness, and surface coatings are compared. Batch

adsorption experiments are performed to determine the effect of pH on (1) protein adsorption and (2)

protein adsorption when divalent cations are present. Membrane active layer and fouling layer surface

properties are measured using microscopy techniques. Distinguishing between the polyamide and the

protein is challenging as both are composed of the same elements: hydrogen, carbon, oxygen and

nitrogen. The protein is modified with a known quantity of halogen to differentiate them. Rutherford

backscattering spectrometry (RBS) shows protein adsorption decreases to zero with increasing pH.

Membranes with more terminal amine groups have higher protein adsorption, indicating the protein

adsorbs to polyamide protonated amines. In the presence of a divalent ion, protein adsorption varies

similarly to the protein only adsorption below the pKa of the membrane carboxylic group. Above the

membrane carboxylic group pKa, protein adsorption is higher and never zero when divalent ions are

present. It is hypothesized because of the presence of the protein at high pH that divalent ion bridging

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occurs between the deprotonated carboxylic acid on the membrane surface and a negatively charged

group on the protein.

Anna Fedders

Evaluation of infrared spectroscopy as a tool for biomass characterization in microalgae

Algae are increasingly being investigated for use as feedstock for biofuel production, hydrothermal liquefaction, and other industrial processes. For each of these potential applications, rapid and accurate characterization of algal biomass as carbohydrate, lipid, and protein fractions is essential. Traditional wet chemistry methods typically require large amounts of biomass, are time consuming, and frequently involve the use of hazardous chemicals. Recently, novel spectroscopic methods have been proposed which use near-infrared (NIR) or fourier transform infrared (FTIR) spectroscopy to quantify algal biomass composition. While numerous methods have been published on the subject, more work is needed to determine how data can be best standardized and analyzed to maximize method precision and accuracy in both pure- and mixed-culture systems. Suggestions for addressing these knowledge gaps will be proposed.

Daniel Mosiman

Comparison of Fluoride Removal Capacities by Different Low-Cost Materials

Fluoride is a common constituent of natural waters due to the abundance of fluorine in the Earth’s crust.

Consequently, toxic fluoride exposure is endemic, chiefly in East Africa, India, and China. The World

Health Organization (WHO) estimates that at least 200 million people are at risk for acquiring dental

fluorosis, resulting in the browning of teeth, and that more than 10 million are at risk for acquiring skeletal

fluorosis, causing bone deformation, joint pain, and crippling. Most of these people cannot afford the high-

tech defluoridation solutions or manage their high maintenance, driving research for low-cost, simple,

effective, and socially acceptable treatment options. Due to these constraints, researchers favor

adsorption processes, and bone char (BC), a naturally derived hydroxyapatite (HAP, chemical formula:

Ca5(PO4)3OH), is well suited. However, like many fluoride adsorbents, BC’s fluoride adsorption capacity

is dismally low (~3-5 mg-F/g-BC); in addition, BC cannot be easily manipulated in a way that could

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enhance its fluoride adsorption capacity, such as increasing its surface area or modifying its crystalline

structure. Furthermore, the mechanisms by which fluoride is adsorbed by HAP are not understood well,

which limits the potential to modify HAP in a. This research focuses on fluoride removal by HAP pellets

that mimic BC. Due to its production process, which essentially comprises of precipitation and

compaction, these pellets can be manipulated rather easily. During compaction, sawdust (d < 0.6 mm)

was incorporated into the HAP. The dried pellets were then sintered at 500°C to remove the sawdust and

thereby create a higher surface area. Fixed-bed columns were used to compare fluoride adsorption

capacities of BC, HAP, and the manipulated HAP. In addition, effluent concentrations of relevant

parameters were monitored and analyzed to help elucidate fluoride removal mechanisms.

Olabimpe Akinbobola

Resilience to Climate Change in Developing Countries

Climate change is when there is a variation in an average weather of a region. This variation leads to the

occurrence of extreme and severe weather conditions that exacerbate the environmental conditions (air

and water quality, food security) of the affected region.

The effect of global warming caused by greenhouse gases and other natural sources are known to be the

paramount source of climate change. Consequently, climate change causes droughts, rise in

temperature, flood, rise in sea level, intense rain, fire, extreme storms, snow melts, ecological effects, and

many other direct/indirect impacts. These impacts are sustainable if the society could develop resilience

through adaptation, and other adaptive management methods that could help minimize vulnerability.

Resilience can be measured as a way a community reverted to an equilibrium state after a disturbance,

or when a community resists change and persistency to recover after perturbation (Brock, 2003).

The developing countries have so many factors working against them, most predominantly, lack of

financial support, water and food insecurity, poor infrastructure and technologies. All these factors

exacerbate their vulnerability.

Megan O'Donnell

Use of Low Impact Development (LID) Strategies to Manage Stormwater Runoff

Stormwater runoff increases with impervious land cover and can be an issue for urban areas where a

substantial portion of surfaces are impervious. Stormwater runoff impacts water quality by transporting

sediments and pollutants it comes into contact with as stormwater sheet flows to drainage features.

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Impacts of stormwater are exacerbated in urban areas that utilize a combined sewer system (i.e.

wastewater and stormwater are combined and transported to a treatment facility in the same sewer

system) due to combined sewer overflow (CSO) during large storm events. Some cities have begun

implementing low impact development (LID) strategies when updating and renovating stormwater

infrastructure in order to reduce the aforementioned impacts. LID designs may include permeable

pavements, bioretention features, and rain capturing devices. This project will examine the need for LID

strategies and explore case studies in which such strategies have been implemented.

Ran Mei

Microbial community response of a mesophilic methanogenic enrichment to temperature

perturbations

Anaerobic digestion (AD) provides an environment for microorganisms with different metabolic functions

to cooperate and metabolize complex organic compounds to methane and CO2. Previous studies have

reported that temperature control was essential in AD operation, and temperature fluctuation could lead to

process instability and in some cases process failure. Nevertheless, the understanding on how AD

microbiota respond to temperature shocks is rather poor. It remains unclear which group(s) of microbes

are vulnerable to heat shock and which are responsible for the recovery of substrate degradation after

heat shock. To systematically address these questions, a mesophilic benzoate-degrading methanogenic

enrichment was exposed to different levels of temperature perturbation from 45°C to 70°C for 5 or 15 min.

Comparing to control treatment, we observed three types of methane production profile: not inhibited at

45 and 50°C, inhibited first and recovered later at 55 and 60 °C, inhibited and not recovered at 70°C.

These responses could be further explained by the microbial community analysis based on 16S rRNA-

and rRNA gene-targeting sequencing. A Syntrophus-related population, the major benzoate-degrading

syntroph, was highly correlated to heat shock temperature, and its abundance was crucial to the

restoration of benzoate degradation after the perturbation. In contrast, the abundance of methane

producers was relatively stable regardless whether methane production was inhibited. Different response

patterns were observed with other bacterial species, and could be used to understand their potential

physiological traits and ecological niches in the AD microbiota. For example, significant increase in

abundance was observed with a Firmicutes-related population (>50% in total population), which is likely a

spore-forming biomass degrader. Growth was stimulated for members of WWE1, Spirochaetes,

Bacteroidetes and Thermotagae, and inhibited with another member of Spirochaetes. While the exact

roles of these minor microbial populations are unknown, they are ubiquitous and functionally important in

AD. Overall, temperature perturbation provided an effective way to shed insights into the microbial

36

populations in AD, and can further generate knowledge on how to deal with unexpected heat shock, a

common accident, thus improve the stability and performance of AD processes.

Fabian

Development of a genetic algorithm model for green infrastructure optimization design to reduce

nutrient pollutant load in the receiving stream

Green infrastructure has been widely studied and reported as part of Low Impact Development (LID)

approaches to replace or complement existing storm water strategies.

Research on green infrastructure focused on water quality is often limited to laboratory work testing

different materials, substrates or configurations. However, the modeling of the water quality resulting from

a green infrastructure network has not been widely explored at the watershed scale.

Nutrients are particularly interesting due to some evidence and consistent results that show Green

Infrastructure, such as rain gardens or green roofs, actually can be a source instead of a sink of nitrates

and phosphates. In riparian watersheds the nutrient export to a receiving stream could lead to

eutrophication conditions and affect equilibrium of the ecosystem.

Different studies have been conducted in order to optimize the benefits of green infrastructure such as

peak flow reduction and total volume of storm water. Following the same approach, the total load of

nutrients exported to the outlet of an urban network can also be optimized. Genetic algorithms are

adaptive methods that can be used for single- and multi-objective optimization; they are based in the

principles of genetic evolution and natural selection. Similar to natural behavior, a genetic algorithm has a

population of individuals (chromosomes), and each one is a feasible solution to a given problem. Each

“individual” is evaluated with a model of the green infrastructure network to evaluate its fitness

(performance relative to the design criteria). The best solutions are selected to form new solutions

(offspring) in a process that will repeat until the algorithm converges to the best designs. Genetic

algorithm are widely used in optimization problems where the objective function is discontinuous,

nonlinear, stochastic, or where the data are not reliable.

The research I will discuss is focused on the development of the genetic algorithm optimization model in

order to achieve the best green infrastructure configuration and design, finding what spatial and temporal

scale works better for an urban watershed model.

Kevin Hade

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Comparing long-term and short-term emission impacts from infrastructure using a simple model

Existing infrastructure such as building shells or roads have long lifetimes, and thus the emissions they

cause can persist well into the future. Although present-day emissions from these sources are quantified,

long-lived infrastructure can also influence future development and transportation choices and shape

emission trajectories and climate as a result. To understand the impacts of infrastructure on expected

future emissions, it is important to quantify how emissions respond to long-lived infrastructure taking into

account the carbon commitment or lock-in resulting from the infrastructure’s long lifetime and the resulting

response of Earth’s temperature. In this study a simple model was used to estimate the Earth’s

temperature response to a time-dependent emission function. Outputs from this model are used to

compare the short-term and long-term climate forcing that result from emissions from infrastructure over

time.

Qing Wei

Evaluation of the Effectiveness of the Forest Program of the Convention on Biological Diversity

Forests play a crucial role in the economy and social development of many countries. More than 1.6

billion people depend to varying degrees on forests for their livelihoods. Unfortunately, forests continue to

be lost and degraded at a high rate. The goals of this research were to identify challenges in

implementing the forest biodiversity protection programs in developing countries and provide

recommendations for improving its effectiveness. The implementation of the CBD has been generally

difficult because there are major problems in biodiversity conservation and equal sharing of benefits

arising from biodiversity in developing countries. The first significant challenge in Bangladesh is to clearly

define the terms “forest,” “deforestation,” “reforestation,” and “afforestation” where misunderstanding and

misinterpretation are likely to arise. Second, the planned protected areas in Bangladesh remain

unprotected due to the increasing deforestation rate and population. Third, the government of Bangladesh

failed to manage the national land uses. Although 193 countries ratified the CBD, a number of parties

have difficulties in implementing it. The author gave recommendations for improving the effectiveness of

the CBD. First, in order to promote gain credits, developed countries can support technical and financial

supports to developing countries, assisting developing countries in the development of conserving forest

and compensating developing countries for the preservation of tropical areas. Second, effective law

enforcement is required as a basic foundation of any conservation strategy, especially important for the

implementation of the CBD, requiring protection and/or the restoration of “legal forest reserves” and

“areas of permanent protection” on all proprieties. Third, integrate the diverse regulations and public

policies, new opportunities and incentive mechanisms for forest protection and restoration, and various

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independent projects and programs carried out by governments and NGOs into a single and

comprehensive strategy for establishing networks of sustainable landscapes.

Diana Kapanzhi

Life Cycle Assessment of a Multifunctional Woody Polyculture: advancing goals for sustainable

food production through perennial agriculture.

The goal of the iSEE funded project is to establish UIUC as a global leader in perennial polyculture

research. A woody polyculture cropping system has several advantages over conventional annual

cropping, including storage of carbon, vertical layering of production, and diversity of products. As our

component of this interdisciplinary project, this study will establish a comparative Life Cycle Assessment

to characterize environmental implications of a farm’s transition from a corn-soybean rotation to a

perennial polyculture cropping system. Data will be gathered from a 50 acre start-up farm as well as the

established farms, relevant literature, and interviews with farmers. The main objective is to characterize

the environmental implications of a transition from annual cropping to perennial. It is expected that the

long term implications of this transition to a multifunctional polyculture system will yield reduced runoff

flow, reduced pesticide concentrations, increased soil carbon retention, and improved surface and

groundwater quality.

Minmin Liu

Assessment of drinking water disinfection by using flow cytometry

Disinfection is an important process to control microbial risk of drinking water. Chinese standard method

to evaluate disinfection is plate culture method, which has its limitation. Flow cytometry along with

fluorescent probes can count bacteria one by one fast and accurately. This method only costs 3 hours

and can detect most kinds of bacteria. It is significant to choose proper fluorescent probes.

New SYTO9-CTC staining protocol is established. Steps are 1) mix sample with 10% volume R2A culture

medium and CTC fluorescent probe (2mmol/L); 2) incubate sample in 37℃ without light for 2.5h; 3) add

SYTO9 stain (1.5µL/mL) and incubate for 5min; 4) detect sample with flow cytometry. Use FL3 channel

as trigger, PMT voltage for FL1, FL2, FL3 channel are 4.5, 4.5 and 6.5V.

SYTO9-PI staining protocol could separate membrane intact bacteria with membrane ruptured. When

chlorine concentration is 1.0mg/L and contact time is 30s, 97% E.coli lost membrane permeability and

S.aureus signals disappear. Chloramine disinfection has the same results but the process is slower. But

39

this protocol can not describe UV disinfection because bacteria signals only separate when the UV dose

comes to 200mJ/cm2.

Use SYTO9-CTC to stain bacteria treated by chlorine and chloramine, it is found that bacteria with

ruptured membrane are still metabolic and viable. SYTO9-CTC staining protocol could evaluate UV

disinfection. Bacteria metabolism rate will slow down after UV exposure;there is a logarithmic relationship

between them. 40mJ/cm2 dose UV responds to 80% metabolic E.coli. Medium pressure UV has more

significant disinfection than low pressure UV.

Valerie Bauza

Identifying key drivers of successful national sanitation plans in low- and middle-income

countries

Globally, 2.5 billion people still lack access to improved sanitation facilities. Improving national sanitation

plans, including how sanitation services are managed and sanitation policies are implemented, is critical

for improving sanitation access. However, as of 2014, less than one-fourth of low- and middle-income

countries had sanitation plans that were funded, implemented, and regularly reviewed. Human and

financial resource constraints are often cited as major factors impeding greater improvements in the

sanitation sector, but evidence-based policy decisions related to sanitation are lacking. This poster

presents the analysis of associations between national policy and capacity characteristics with sanitation

access improvements over time for 38 low- and middle-income countries. The analysis uses data from

the UN-Water Global Annual Assessment of Sanitation and Drinking-Water reports and the World Health

Organization/UNICEF Joint Monitoring Program for Water Supply and Sanitation datasets.

Recommendations will be made regarding specific policy components and country capacity resources

that appear to be the strongest drivers of improvements in national sanitation access.

Conghui Huang

The effect of biofilm roughness and hydrodynamic condition on particle attachment in COMSOL

Biofilms grown on the pipe surface can be a threat to drinking water safety because it can accumulate

and release pathogens. However, factors contributing to pathogen accumulation and detachment are still

under investigation. To explore the role of biofilm roughness and pathogen transport, we experimentally

quantified adhesion of Legionella pneumophila on simulated drinking water biofilms, and conducted

simulation of particle deposition on simulated biofilm surface obtained from cross-sectional grown biofilm

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in lab. Biofilms used in this study were grown from simulated drinking water for different time period and

thus different roughness, which was determined by OCT. To further exploring the mechanisms of how

roughness controls adhesion, we also conducted particle- tracing simulation using COMSOL

Multiphysics. Relatively rough and smooth biofilm profiles obtained from OCT images were used in

simulation of particle deposition, and adhesion of particles under same hydrodynamic conditions used in

Legionella adhesion experiments was quantified. The results revealed that surface roughness creating

local hydrodynamics facilitate the interception of particles with surface roughness, thus increase particle

adhesion. The simulation results agreed with experimental results. The possible application from this

study can be modification in biofilm monitor and treatment to reduce the risk of potential bacterial

exposure from drinking water distribution system.

Anshoo Narula

Feasibility of Recharge shafts/Injection wells for groundwater recharge in Patan district, Gujarat,

India

The poster will be based on a reserach paper I published in International Journal of Advanced Research

in Engineering and Applied Sciences on the topic "Feasibility of Recharge shafts/Injection wells for

groundwater recharge in Patan district, Gujarat, India" . For the industrial development, agricultural &

economic growth the demand of groundwater has increased in north Gujarat alluvial plain. The

groundwater draft exceeds the groundwater recharge resulting in over exploitation of groundwater

aquifers. This has resulted in continuous decline in water levels and reduction in the yield of the tube

wells. Due to poor rainfall reliability and recurring drought conditions, the area could never recover the

deficit of water extracted from groundwater resources. The artificial recharge to groundwater can only

sustain the water levels or can arrest the rapid depletion of groundwater rate. The part of Patan taluka in

Gujarat, India is selected for the construction of artificial recharge structures near the large storage village

ponds. It is proposed to construct artificial recharge structures in seven villages of Patan taluka near

these village ponds. The recharge potential is calculated taking 40 rainy days taking average rainfall as

770mm. If the recharge shaft is connected to the ponds at a depth, it is able to utilize the

storage of ponds and recharge potential can then be calculated for a period of 180 days (pre-monsoon

and post-monsoon period). Thus calculating the runoff potential of seven recharge structures and

considering the catchment of the area, the plan is considered

feasible for recharge in seven villages of Patan Taluka.

Zhongwen Ren

41

Airport-related air pollution

Now a day, because the increasing air pollutants risks on human health, more and more scientific

community and governments pay attention on how to improve poor air quality. Moreover, air pollution can

also decrease visibility and damage materials in buildings. As the rapid growth of air transport volumes,

people attract a really high level of interest in the airport emissions(AEs). The one of major source of

emission at an airport is aircraft exhaust. There are also many other sources which are presenting in

modern airports and emitting air pollutants. For example, there are large fractions of particulate matter

created by the air flow from the aircrafts. In addition, airport ground service equipment (GSEs) such as a

large number of passenger buses, baggage and food carriers, cleaning and lavatory services machines

also can emit the pollutants and impact the air quality. Additional sources may also be present at airports,

including high-temperature hot water generators, emergency generators and boilers that service both

terminals and support buildings. Moreover, because large airports are always located near to the big city,

they have a huge impact on the environment that a lot of people lived and affect for the human health.

The goal for this paper is to describe the research on aircraft and airport-related emissions, in order to

summary key characteristics for airport-related pollutants and the impact on air quality.

Junhui Liao

Application of Standalone Down-flow Hanging Sponge Reactor for Food Processing

Wastewater

Standalone Down-flow Hanging Sponge (DHS), an aerobic biological reactor, is studied to find the

possibility and performance for treating high organic loading food processing wastewater on site. The

research objective is to treat the wastewater to meet the municipal sewer discharge standard over long

term operation. Hydraulic retention time (HRT), additional nutrient loading and pH range are all the

objective parameter that this research is aiming to define in order to achieve the ultimate TOC and COD

removal performance for this reactor. Three DHS chains were established by using 30 sponges each and

saturated with sludge solution before hanging one by one as a chain. Reactors were feeding by synthetic

wastewater(1000 mg/L TOC, 45mg/L total nitrogen and 15mg/L total phosphorus). . pH and HRT are

keeping adjusting according to the effluent water quality. So far with 13 hours HRT and pH 9 the TOC and

COD removal rate can achieve 90%

Fangqiong Ling

42

Core-satellite model and seasonal dynamics in water meter biofilms of drinking water

distribution systems

Background: Drinking water distribution system is an important part of urban infrastructure, and the

microbial communities enclosed in the system are an important component of the built-environment

microbiomes. Examination of the biofilm communities has traditionally based on sampling on certain

points in the system. This study aimed to represent the diversity of biofilm microbial communities in a

drinking water distribution system (DWDS) with a spatio-temporal design and examine their response to

environmental factors.

Methods: The model system for this study was a mid-size distribution system that delivers conventionally

treated water from central Illinois groundwater. Household water meters (n=213) were used as sources of

biofilms, which allowed spatial and temporal replication over a 2-year time span. Microbial communities

were analyzed via 16S rRNA gene pyrosequencing. Sequences were processed with MOTHUR, and an

OTU-based analysis was conducted to compare biofilm and planktonic microbial communities.

Hypothesis testing based on similarity matrix was conducted with PERMANOVA and ANOSIM.

Results: Positive correlation between local abundance and regional occupancy was observed, and thus

core populations were defined in light of a “core-satellite” model. These core populations are low in

numbers of OTUs, but occupied the majority of sequences. Hypothesis testing on community similarity

indicates that seasonal variation explained the most of the variation. Key OTUs corresponding to

seasonal variation were further identified, suggesting the presence of cyclic fluctuation in core

communities.

Conclusions: Our findings indicate that seasonal variation is important in the community dynamics of

DWDS biofilms. The core-satellite model is useful in understanding a spatially-expansive water system.

The results contribute to the scholarship of “built environment microbiome” and shed light on ecology-

guided monitoring of drinking water systems.

Yida Fang

Biological and Biologically Mediated Abiotic Transformation of Contaminants of Emerging

Concern in Anaerobic Soils

Freshwater consumption and scarcity leads to a more frequent usage of wastewater for agricultural

irrigation in the effort to reduce water cost as well as nutrient cost. The presence of a wide range of

pharmaceuticals presented in wastewater has raised concerns due to such application. Because majority

of them are not regulated by government agencies, many of the pharmaceuticals are able to accumulate

in plants roots that eventually end up to human consumption. In this project, the fate and transport of four

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commonly used pharmaceutical and personal care products (PPCP), Sulfamethoxazole (antibiotics),

Carbamazepine (anti-epileptic drug), Iopromide (contrast medium), and Norfloxacin (antibiotics), are

observed under various terminal-electron accepting processes (TEAP), such as nitrate, sulfate, and iron

(III) reducing environment. The degradation process of the four PPCPs is performed in lab scale reactors

that have a 3:1 water to soil ratio. LC tandem MS is used to detect the exact concentration change of the

PPCPs throughout a period of time. Moreover, the daughter products of each parent compound after their

degradation are also predicted using LC – MS. By predicting the daughter products, the specific

functional group that triggered the PPCPs oxidation/reduction reaction is identified, therefore, providing a

basic understanding of the PPCPs degradation pathway in anaerobic soil.

Kia Alexander

Assessing the environmental impacts of agricultural intensification in Sub-Saharan Africa – an

analysis of soybean development in northern Ghana. The US Agency for International Development’s (USAID’s) Soybean Innovation Lab (SIL) is an applied

research for development project employing scientific and socio-economic research efforts to enhance

the production and utilization of soybean in small-holder farming communities in Sub-Saharan Africa.

The environmental assessment of SIL’s work aims to develop a mechanistic understanding of the multi-

scale environmental impacts of soybean agricultural development, which will enable us to make

agricultural management recommendations supporting a transition toward increased food security that is

consonant with long-term environmental protection goals.

In the growing field of research on the environmental impacts of agriculture, few studies have focused on

the impacts of tropical agriculture, which varies markedly from temperate agriculture due to differences in

temperature, soil, and hydrologic regimes. This study provides an opportunity for unique insight into the

influences these conditions have on the environmental impacts of agriculture.

The direct, local environmental impacts of tropical soybean development will be assessed through

environmental quality monitoring at small-holder farms and at SIL’s soybean research site in northern

Ghana. Parameters to be assessed include air, water, and soil quality metrics, and direct and indirect

exposure of humans to agricultural toxins. Broader potential impacts, including land use change,

eutrophication, and effects on greenhouse gas emissions, will be assessed through an agro-

environmental life cycle assessment and the monitoring of long-term trends.

The project is in the preliminary data collection stage. Initial data collection from collaborating researchers

and from visits to the research site and plots of smallholder farmers are being used to inform the long-

term data collection plan for the environmental assessment.

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Jerry Hsu

Electric field disinfection

Electric field disinfection is a new way to kill or disable microorganisms so that they cannot endanger

human health. Some bacteria can be harmful to human health when intake on high density. And human

sterilize their tableware and living environment to make sure that they don’t affect our bodies. Electric field

can be used to perform this task.

Electric field disinfection can be widely used on air conditioners, air-cleansing machine, and to sterilize

lab equipment. Recent research have proved that it’s more effective to disinfect bacteria living on solid

media, like tables, floors, etc., and not relatively efficient on killing air-borne species. But due to its area

effectiveness, electric field can be used in wide range of media.

Since electric field disinfection doesn’t require temperature and pH change of the media, it doesn’t

change the majority of the chemical reactions in the media. Many media required for disinfection are

coupled with tons of chemical reactions, and are easy to be halted if temperature or pH changes. In most

of the cases, disinfection treatment process is isolated from other treatment processes. After disinfection,

pH and temperature are adjusted back to the required state for further chemical reactions to occur.

Electric field disinfection can proceed simultaneously with other chemical reactions, thus provides us with

a new way to reduce cost for disinfection by saving the money for additional tanks and supplies to adjust

the medium back to it’s formal state.

Yang Song

Arsenic Removal via Bone Char Filtration

Arsenic in drinking water is strictly regulated by USEPA because its probable health effects. One way to

remove arsenic in the drinking water is via bone char. The bone char is porous, black, granular material

produced from charring animal bones. Pretreatment is required to convert As(III) to As(V). Common

oxidants include permanganate, peroxide, atmospheric oxygen. To optimize the performance of removal,

the adsorption kinetic need to be studied. The study shows that optimum removal was achieved in pH

range between 9 and 13, contact time of 30 minutes and adsorbent dosage of 0.8 g/l. The removal is

usually higher for the lower initial arsenic concentration. The bone char combined with ion exchange resin

and membrane techniques is a powerful tool to remove the arsenic.

Minhao Lu

45

Radon, a non-negligible health risk

Radon is the most common radioactive element appears in people’s life. Because it’s colorless and

odorless, radon becomes an invisible but non-negligible health risk. According to USEPA, radon is the

second main cause of lung cancer after smoking, and the number one cause among non-smokers. Due

to radon gas’s high density, it may accumulate in the basement of one’s home, cause long-time low-

concentration exposure to radon. EPA recommends all house take a radon test in the lower part of their

house, and any house has a radon level higher than 4 pCi/L should fix their house to lower the Radon

threat. This poster is a literature review about the Radon’s radioactivity, risk to health, its common

distribution in US and general mitigation ways to lower the risk.

Erhu Du

Evaluating the impacts of an agricultural water market in the Guadalupe River Basin, Texas: An

agent-based modeling approach

Agriculture comprises about 80 percent of the total water consumption in the US. Under conditions of

water shortage and fully committed water rights, market-based water allocations could be promising

instruments for agricultural water redistribution from marginally profitable areas to more profitable ones.

Previous studies on water market have mainly focused on theoretical or statistical analysis. However,

how water users’ heterogeneous physical attributes and decision rules about water use and water right

trading will affect water market efficiency has been less addressed. In this study, we developed an agent-

based model to evaluate the benefits of an agricultural water market in the Guadalupe River Basin during

drought events. Agricultural agents with different attributes (i.e., soil type for crops, annual water diversion

permit and precipitation) are defined to simulate the dynamic feedback between water availability,

irrigation demand and water trading activity. Diversified crop irrigation rules and water bidding rules are

tested in terms of crop yield, agricultural profit, and water-use efficiency.

The model was coupled with a real-time hydrologic model and run under different water scarcity

scenarios. Preliminary results indicate that an agricultural water market is capable of increasing crop

yield, agricultural profit, and water-use efficiency. This capability is more significant under moderate

drought scenarios than in mild and severe drought scenarios. The water market mechanism also

increases agricultural resilience to climate uncertainty by reducing crop yield variance in drought events.

The challenges of implementing an agricultural water market under climate uncertainty are also

discussed.

46

Cunqian Li

Indoor Air Quality

Indoor air quality is essential to human health. Studies show that people spend over 90% of their lifetime

indoor. Lower air exchange rate in indoor environment can accumulate the air pollutants. According to

U.S Environmental Protection Agency (EPA), poor indoor air quality is been regarded as a top

environmental health risk. The poster will discuss the source of pollutants such as dust, molds, radon,

smoke and fumes, or VOC and their potential harm upon human beings. The poster will also introduce

the mechanism of several indoor air quality control techniques such as filtration, ventilation, adsorption,

and absorption. The poster will compare several indoor air quality control devices including photo catalytic

oxidation air purifier, electrostatic precipitator, high efficiency particulate air filtration, and active carbon by

their advantage and disadvantage.

Wen Tang

Sustainable Design of Microalgae Reactor for Biomass Production

The objective of this project is to design a closed microalgae system using secondary treated municipal

wastewater as nutrient resource in EI Paso, TX. The aim of the design is to achieve the annual biomass

production goal of 100,000 kg and maximize the profit with minimum environmental impact. Life Cycle

Assessment (LCA) using SimaPro and Life Cycle Cost Analysis (LCC) are conducted to evaluate different

microalgae candidates (Chlorella vulgaris and Scenedesmus obliquus) and determine the optimal value

of critical design parameters (recycle ratio and diameter of the tube). The results show that when using

Chlorella vulgaris and with the tube diameter of 0.25m and recycle ratio of 1.9, the unit cost of biomass

production reaches the lowest value and the environmental impact is minimum. However, since the cost

is much higher than the income, the project cannot be profitable, which is consistent with the conclusions

of other researches. The two main contributors of total cost are the tubes and electricity.

Hao Chen

Adsorption Mechanisms of Thallium(I) and Thallium(III) by Titanate Nanotubes: Ion-Exchange

and Co-Precipitation

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Owing to hydrothermally-synthesized titanate nanotubes (TNTs) have unique physicochemical

characteristics, large surface area, charged surface and small sizes [1], this research indicated that TNTs

show great capacities to absorb thallium ions, which is highly toxic especially to mammals if it is in high

concentration, and the amount of thallium has increased with the development of industrialization [2-3].

Two primary oxidation states of thallium are Tl(I) and Tl(III). In this research, the Langmuir mode can best

fit the adsorption of Tl(I) using TNTs. However, for Tl(III), when the Tl(III)’s concentration is low, the

adsorption is mainly ion-exchange with Sodium ion, and Tl(III) will co-precipitation with TNTs forming

Tl(OH)3 if the concentration of Tl(III) is high [4]. What’s more, the TNTs’s abilities to adsorb Tl(I) and Tl(III)

show positive correlation with pH. Finally, this research also illustrates TNTs can be reclaimed, which

means TNTs can have a better adsorption ability for thallium again after using HNO3 for desorption and

NaOH for regeneration [4]. In this circumstance, TNTs can be as a potential material to remove thallium in

the wastewater treatment plant.

Rishabh Shah

Hygroscopicity and cloud condensation nuclei (CCN) activity of biomass-burning aerosol

Primary organic aerosol (POA) particles can act as CCN and indirectly affect climate by altering the

microphysical properties of clouds. Of the total POA emissions from combustion, 88% is estimated from

biomass burning. Anoxic conditions in the core of a burning piece of biomass lead to emission of organic

carbon (OC) as gas and subsequent condensation into aerosol particles. Several atmospheric processes,

collectively termed ‘aging’, change the hygroscopic nature of OC. The purpose of this research is to

identify and quantify the reactions that affect the climate-relevant properties of these ubiquitous aerosols

so that their properties at emission can be explicitly linked to direct and indirect radiative forcing. We

conducted bench-scale experiments on OC aerosol to determine its hygroscopicity and changes in CCN

activity upon aging. OC aerosol was aged with controlled concentrations of anhydrous NH3 and O3, two

common reactive trace gases in the lower atmosphere. The relative humidity (RH) during aging was

controlled to simulate RH conditions in the lower atmosphere (5-85%), as water taken up by particles may

participate in the aging reactions. We use the activation diameter (D50), the diameter at which 50% of the

total aerosol particles are activated, as an indicator of CCN activity. A reduction in D50 implies greater

CCN activity. We measured the size growth factors of fresh OC aerosol at RH ranging from 40 to 90%.

Two hygroscopic tandem DMA tests with κ-Köhler model fits gave similar results of κ = 0.08±0.005 and κ

= 0.07±0.018. All CCN measurements were done at a supersaturation of 0.3%. OC aged with 10 ppmv

NH3 had minimal change in D50, less than 5% reduction, for either low and high RH during aging (5%

and 85%, respectively). OC aged with high concentration of NH3 (875 ppmv) at 70% RH had a 23%

decrease in D50. Aging with 100 ppbv O3 (RH < 5%) resulted in no change in D50 of the OC, although

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the slope of the activation curve was steeper than that of fresh OC. This finding indicates that activation

behavior is more consistent across the particle population after aging.

Trang Vu

The formation of nitrogenous disinfection by-products from the reaction between

dichloroacetaldehyde and monochloramine

A mandatory step in a drinking water treatment plant is disinfection in which a powerful oxidant was

employed to remove harmful pathogens threatening the human health. However, some by-products from

this process, which are proved to be toxic, become one of important health issues. Disinfection by-

products (DBPs) are formed from the interaction of the disinfectant (e.g. chlorine or chloramine, etc.) and

the precursors naturally occurring in water such as bromide, aldehyde, and other organic matters. Only

DBPs produced by chlorination such as trihalomethanes (THMs) and haloacetic acids (HAAs) have been

studied and regulated. Newly proposed regulations with stricter standards of these compounds lead to a

switch to alternative disinfectant (e.g. ozone or chloramines), and thereby can promote the formation of a

new DBP class. On the other hand, the researches on nitrogenous DBPs, which contain nitrogen in their

structures, have not been conducted widely though their toxicity is much higher than the regulated

groups. The purpose of this study is characterizing the formation pathway of N-DBPs from the reaction

between dichloroacetaldehyde and monochloramine. The results suggest that dichloroacetonitrile and

dichloroacetamide, two prevalent compounds among N-DBP group found in drinking water, were actually

produced from this reaction. In this work, the equilibrium rate constants of the reversible reaction between

dichloroacetaldehyde and monochloramine were also estimated.

Yalin Li

Model Comparison and Modification for Algal Hydrothermal Liquefaction

With the current climate changing background and increasing research interests in renewable energy,

squeezing energy from algae has raised great attention. Unlike terrestrial plants like corns and sugarcane

that are required to produce ethanol, a typical first-generation biofuel, algae can be cultivated in aquatic

environments like sea and wastewater. The reduction in desire for land, especially farmland, may be a

great progress towards the end of paradox choice between “Feed the poor, or the rich’s car?” Thus

producing biocrude and biodiesel, which are now commonly referred to as second generation biofuels,

has become a “hot spot” for recent work. In order to convert algae into biofuel that can be later upgraded

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as a potential substitute for fossil fuel, an emerging technology, Hydrothermal Liquefaction (HTL) can be

employed. Several models have been put forward to illustrate the relationship between crude algae

composition and the HTL yield, but more work is required to determine the accuracy and applicability of

these models, which is exactly what my current research focused on.

Fransico Mena Gonzalez

Modeling the Cloud Condensation Nuclei Activity of Aerosols from Residential Biofuel

Combustion

Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The

change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty

in modeling the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide

estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics

(coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume for the first

15 seconds after emission. We found that aerosol-scale dynamics only affect activation during the first

few seconds of evolution, after which the CCN efficiency reaches a steady state. The condensation of

semi-volatile species is the main factor driving aerosol activation; dilution rate and volatility of plume

gases had no significant effect. Our results provide a theoretical basis from which one can improve

estimates of the aerosol effects on clouds.