Fall 2012 Newsletter


Department Research

Environmental Engineering

Applications of Cell Entrapment and Bioaugmentation for Water Pollution Control

One of the projects in this research area involves the use of cell entrapment process for removing high-level nitrogen in supernatant from anaerobic digesters. Applications of cell entrapment for water pollution control have been mostly on low strength wastewater. The high cell density property of entrapped cell systems has not been taken an advantage of; entrapped cell systems should be effective for high strength wastewater due to high number of cells available to biologically transform target contaminants.Free cell bioaugmentation has been widely used in pollution control. One of the weaknesses of free cell bioaugmentation is the proneness to cell loss from the system. This research investigates the use of entrapped cells for bioaugmentation, in particular for removing a herbicide from agricultural infiltrate. The benefit of bioaugmentation with entrapped cells is the ability to retrieve the augmented cells for reactivation.

Involved faculty include: Dr. Eakalak Khan

Environmental Sensors

Design of micro- and nano-sensors for environmental studies is the focus of this research. The research concentrates on the development of robust and easy to make metal and metal-metal oxide sensors.

Involved faculty include: Dr. Achintya Bezbaruah

Nanoparticles for remediation

Metal nanoparticles are used for the remediation of environmental contaminants in soil and water. However, the lack of ways for efficient delivery of these particles to the target compounds remains a major hurdle. The researchers at Civil Engineering are working on the development of appropriate delivery vehicles for such nanoparticles in collaboration with Center of Nanoscale Science and Engineering (www.ndsu.edu/cnse/). The research is also focusing on new nanoparticle development and kinetic studies for various contaminants.

Involved faculty include: Dr. Achintya Bezbaruah

Fundamentals of Cell Entrapment for Water Pollution Control

Tremendous progress has been made in fundamental work to understand the behaviors of entrapped cells used in the food, pharmaceutical, and biomedical applications, particularly on their physiology. The goal of this research is to advance a foundational understanding on the use of cell entrapment in wastewater treatment. The effects of cell entrapment on growth rate, metabolic activity, cell morphology, cell surface properties, genetic material quantity and stress of bacteria cultures encountered in activated sludge are investigated. Techniques in molecular biology and nanotechnology are used to determine what lies beneath the performance of entrapped cells.

Involved faculty include: Dr. Eakalak Khan

Treatment Wetland

Constructed treatment wetlands mimic their natural counterparts and they are adoptable to small communities. The present research interests in the department are on phosphorous removal, greywater treatment, groundwater organics removal, modeling, and conceptual design of constructed wetlands.

Involved faculty include: Dr. Wei Lin, Dr. Eakalak Khan, & Dr. Achintya N. Bezbaruah

Water Resources Engineering

Stochastic Analysis of Temporal and Spatial Characteristics of Droughts

Selected Palmer Drought Severity Index stations

De-trended Fluctuation Analysis of PDSI data of Station 084

Research Statement/Motivation
Societal vulnerability to droughts of devastating consequences has come under scrutiny time and again in the history of mankind. Recent droughts in the North American Plains are no exceptions. The resulting acute water shortages and lower or no crop yields have significant impact on the economy. The magnitude of impact on society and economy depends on the severity, duration and the spatial extent of droughts. Typically, past investigations focused on identifying dominant frequency components in the climatologic and hydrologic time series for improving modeling and simulation of hydrological variables with exogenous input. Hydrologic variables over longer time scales could be governed by differing processes mechanisms. Therefore, trends and the correlations need to be separated to analyze long term correlations. Though classical tools such as auto correlation function and spectral analysis can provide preliminary indications for the presence of long range correlation, it may be difficult to use them unambiguously to determine the scaling exponent. In recent years several advancements have been made, particularly in the investigation of long-term persistence.

Research Methods
Evolutionary spectral analysis, Detrended Fluctuation Analysis, and Rescaled Range Analysis.

Major Results and Conclusions

Funding Sources: None

Investigators: G. Padmanabhan

Contact information: Dr. G Padmanabhan
Geospatial Analyses of Drought Impact and Severity Using Remote Sensing and GIS

Research Statement/Motivation
An analysis of spatial and temporal variance of drought impact may offer an unbiased glimpse into factors that may dictate drought severity. The objective of this study is to assess spatio-temporal drought impact factors at county level for the entire state of North Dakota, USA. Remote sensing techniques will be used to analyze the drought impact on active vegetation.

Research Methods
Statistical methods, Kriging, GIS, and using satellite imagery.

Major Results and Conclusions
A drought severity spatial variability map was generated from the drought impact values.  Normalized Difference Vegetation Index (NDVI) raster data sets were derived from Landsat 7 ETM+ satellite imagery for the southwest region of the state. This region displayed a significantly impacted drought region.

Funding Sources: None

Investigators: G. Padmanabhan, Adnan Akyuz, Peter Oduor

Contact information: Dr. G Padmanabhan
Filamentous Growth in Entrapped Cell System Treating Domestic Wastewater

Filamentous growth in activated sludge process treating municipal wastewater is a common problem that has been thoroughly studied. However, the susceptibility of entrapped cell systems, which can also be used effectively for wastewater treatment, is unknown. This research investigates the characteristics of filamentous growth in the entrapped cell system. Dominant filamentous types and severity in the system and their effective control method are examined.

Involved faculty include: Dr. Eakalak Khan

Floods and Droughts

Floods and droughts are extreme conditions in lakes, rivers and streams. Characterizing and forecasting them in the time and spatial domains remain a challenge. More challenging is relating them to external forcing functions such as climate change. This research involves stochastic and spatial modeling for simulation and forecasting.

Involved faculty include: Dr. G. Padmanabhan

Non-Point Source Pollution Modeling

This research involves application of distributed parameter models for modeling non-point source pollution.

Involved faculty include: Dr. G. Padmanabhan

Water and Wastewater Engineering

Several ongoing projects in this area include:
Total Maximum Daily Load (TMDL) studies: A large number of water bodies are impaired for their designated used due to discharge of pollutants from point and non-point sources. This research involves water quality sampling, data analyses and model simulations to assist communities and regulatory agencies in developing TMDLs for impaired water bodies.
Wetland Water Quality Studies: This research involves field sampling and model simulations to study the movement of surface and ground water through natural wetland areas and transport of nutrients and other contaminants.
River Flow Studies: Accurate stream flow rate measurement is critical for flood forecasting and water resource management. In collaboration with United State Geological Survey (USGS), this research studies the application of acoustic Doppler velocity meter to improve flow rate estimation under different flow conditions.
Wastewater Nitrification: Ammonia in wastewater discharges may result in toxic conditions for aquatic life and depletion of dissolved oxygen in receiving waters. Nitrification is a process of converting ammonia to nitrate through biological oxidation. Study of nitrification efficiency and kinetic is carried out in a full scale wastewater treatment plant.

Involved faculty include: Dr. Eakalak Khan, Dr. Wei Lin, Dr. G. Padmanabhan,
Dr. Achintya Bezbaruah, & Dr. Robert Zimmerman

Transportation Engineering

Pavement Engineering

This area includes pavement materials, asphalt and concrete, pavement management, performance, rehabilitation and evaluation. Current research areas include the new AASHTO Mechanistic-Empirical Design Guide, modifications to asphalt materials and mixes, construction specifications, QA/QC, and performance-related properties.

Involved faculty include: Dr. Magdy Abdelrahman, Dr. Amiy Varma, & Dr. Don Anderson

Recycled Materials in Civil and Construction Engineering Applications

This area includes characterization of recycled materials, from old civil engineering structures and/or other sources such as industrial waste, as used in new construction projects. Current research areas include the use of recycled tires in asphalt pavement and the use of recycled pavement materials in civil/construction applications. This area also includes enhancing the qualities of recycled materials through the addition of new and virgin modifiers.

Involved faculty include: Dr. Magdy Abdelrahman

Transportation Planning and Infrastructure

Involved faculty include Dr. Amiy Varma & Dr. Donald Anderson

Geotechnical Engineering

Expansive Soils

Expansive soils or swelling clays cause significant damage to infrastructure. This research is focused on understanding fundamental mechanisms of clay swelling. This fundamental research involves developing an understanding of the physics of interactions and using and developing computational chemistry and computational mechanics techniques to bridge length and time scales from molecular to macro. The goal of this research is to develop a thorough understanding of the clay-water system to better control properties geotechnical and geoenvironmental engineering and also to systematically expand use of clays in nanocomposite systems and other applications.

Involved faculty are: Dr. Kalpana S. Katti & Dr. Dinesh R. Katti

Structural Engineering

Continuum Mechanics and Mechanics of Inelastic Continua

Current research in solid mechanics include constitutive modeling of (a) brittle materials such as composites, ceramics, and concrete, (b) metallic and (c) polymeric materials, and material characterization of advanced materials. New mechanics models are being developed including a new damage formulation in correlation with theories of plasticity and fracture mechanics for a class of brittle materials and large strain plasticity models with evolving anisotropy. Of particular interest are damage growth in cryogenic temperature applications in composites, fatigue damage modeling in woven composites and adhesive joint, strain-space failure theories in brittle solids, development of robust and unconditionally stable constitutive solvers, the extension of damage mechanics to large deformation problems in bio-mechanics fields, and materials with evolving substructures, application of non-linear interface mechanics to bi-material bonded interface; development, design and analysis of innovative specimens for fracture characterization.

Involved faculty include: Dr. Frank Yazdani & Dr. Dinesh R. Katti

Structural Mechanics and Engineering

Current research interest in structural engineering and mechanics include nonlinear analysis of concrete shear walls subjected to quasi static and dynamic loads, analysis and design of fiber-reinforced polymer (FRP) structural shapes, characterization of advanced composites and engineering materials. Of interest is the structural healthy monitoring using smart materials, mechanics and application of sandwich plates, interface mechanics, fracture, and durability of hybrid bonded materials (e.g., concrete-FRP, wood-FRP), structural rehabilitate/repair, experimental characterization and numerical simulation of delamination and interface fracture of layered structures. Also of interest is the improvement of the convergence rate with the nonlinear finite element formulation to handle nonlinear constitutive models and thin walled structures.

Involved faculty include: Dr. Frank Yazdani & Dr. Yail Jimmy Kim


Clay-Polymer Nanocomposites

Addition of nanosized clay particles to polymers enhances physical properties of polymers significantly. Composites of nanosized clays and polymers have many application in aerospace, structural materials, sensor design and also biomedical. This research involves development of a simulation based design of clay nanocomposites.

Involved faculty include: Dr. Kalpana S. Katti & Dr. Dinesh R. Katti

Biomaterials Design and Tissue Engineering

Every year about 300,000 joint replacement surgeries are performed in the US alone. Many of these need to be revisited within ten years. There is a need for new materials for replacement of bone, cartilage etc. These can be implants porous scaffolds that tissues can grow on (tissue engineering). The focus of this research is development of biomimetic routes for design of new materials as implants and design of new scaffolds for bone tissue engineering.

Involved faculty include: Dr. Kalpana S. Katti & Dr. Dinesh R. Katti

Biomimetics and Nanotechnology

Nature is both the essence and inspiration for nanotechnology. Design of next generation advanced materials with inspiration from nature is the focus of this research.

Involved faculty include: Dr. Kalpana S. Katti & Dr. Dinesh R. Katti

Multiscale Modeling

Bridging length scales from nanometer to meter using hierarchical and concurrent techniques.

Involved faculty include: Dr. Dinesh R. Katti & Dr. Kalpana S. Katti

Educational Outreach and Collaboration, Undergraduate Research Experience

Nurturing American Tribal Undergraduate Research and Education (NATURE)

Research Statement/Motivation
Nurturing American Tribal Undergraduate Research and Education (NATURE) is a program sponsored by the North Dakota Experimental Program to Stimulate Competitive Research (ND EPSCoR) to strengthen existing pathways for Native American students to pursue careers in science, technology, engineering and mathematics (STEM) fields. Participants of the program include students and faculty from all five tribal colleges in North Dakota, high schools students and teachers from the four North Dakota Indian reservations, and faculty from research universities of North Dakota, North Dakota State University (NDSU) and University of North Dakota (UND).

Research Methods
Summer camps, One‐day STEM academic activities, and engaging the tribal college students in undergraduate research, and mentoring.

Major Results and Conclusions
The NATURE program is being seriously looked at by NSF for emulating nationally.

Funding Sources: National Science Foundation, & ND EPSCoR

Investigators: G. Padmanabhan

Contact information: Dr. G Padmanabhan