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David T. Eddington Supported by NSF, NIH, and the Chicago Biomedical Consortium Rapid Diffusion: microfluidic model of yeast chemotropism

Brett et al, 2012, Lab on a Chip Surface to volume ratio: microfluidic circulating cancer cell diagnostic

Launiere et al, 2012, Analytical Chemistry Laminar flow: electrode calibration device for in vivo cyclic voltammetry

Problem Statement and Motivation • The microscale offers several advantages • Rapid diffusion • Large surface to volume ratios • Laminar flow • Process integration • We leverage these microscale phenomena to achieve new experimental possibilities

Sinkala et al, 2012, Lab on a Chip

Technical Approach • Microfluidic devices are fabricated by soft lithography • Microfluidic channels can be made in several materials • Polydimethyl siloxane (PDMS) • Glass • Ridig Plastics (COC, PMMA, PP, PE)

Key Achievements and Future Goals • Microfluidic models of medicine • Islet transplantation functional assay • Circulating tumor cell diagnostic • Microfluidic models of biology • Microfluidic oxygen control • Regional control of microenvironment in brain slice preparations • Microfluidic yeast reorientation assay • Environmental bacteria isolation • Algae culture in microdevices


Dieter Klatt, Bioengineering Grant Support: Campus Research Board, UIC

Problem Statement and Motivation • Various diseases are associated with imbalances in tissue pore pressure. • Detection of pressure imbalances in the human body may enable early intervention and treatment of disease such as hydrocephalus and portal hypertension. • Currently there is no non-invasive technique for the determination of pore pressure within the human body. • Pore pressure effects the resistance of the surrounding tissue to deformation and thus may correlate with Magnetic Resonance Elastography (MRE)-derived parameters.

Technical Approach

Key Achievements and Future Goals

• Two-layer Ecoflex phantom with hollow center exposed to various pressure values.

• Changes in pore pressure correlate with shear stiffness of surrounding tissue.

• Magnetic Resonance Elastography (MRE) for the determination of the shear stiffness at each pressure value.

• MRE has the potential to serve as a noninvasive tool for the determination of pressure changes within biological tissue. • Future plans: • Increasing the sensitivity of MRE-derived mechanical parameters to pore pressure changes by using 3D SLIM-MRE. • Testing the diagnostic capabilities of 3D SLIM-MRE in animal models of diseases associated with pressure imbalances, such as hypertension and hydrocephalus.


Hui Lu, Ph.D., Bioengineering, Julio Fernandez (Columbia University), Hongbin Li (U of British Columbia)

Problem Statement and Motivation •

Mechanical signals play key role in physiological processes by controlling protein conformational changes

Uncover design principles of mechanical protein stability

Relationship between protein structure and mechanical response; Deterministic design of proteins

Atomic level of understanding is needed from biological understanding and protein design principles

Key Achievements and Future Goals

Technical Approach •

All-atom computational simulation for protein conformational changes – Steered Molecular Dynamics

Identified key force-bearing patch that controlled the mechanical stability of proteins.

Free energy reconstruction from non-equilibrium protein unfolding trajectories

Discovered a novel pathway switch mechanism for tuning protein mechanical properties.

Force partition calculation for mechanical load analysis

Calculated how different solvent affect protein’s mechanical resistance.

Modeling solvent-protein interactions for different molecules •

Coarse-grained model with Molecular dynamics and Monte Carlo simulations

Goal: Computationally design protein molecules with specific mechanical properties for bio-signaling and bio-materials.


Investigators: M. Stroscio, ECE and BioE; M. Dutta, ECE

Problem Statement and Motivation • Coupling manmade nanostructures with biological structures to monitor/control biological processes. • For underlying concepts see M. Stroscio and M. Dutta, Integrated Biological-Semiconductor Devices, Proc. of the IEEE, 93, 1772 (2005) and Biological Nanostructures and Applications of Nanostructures in Biology: Electrical, Mechanical, & Optical Properties, edited by Michael A. Stroscio and Mitra Dutta (Kluwer, New York, 2004). TsaiChin Wu, Guijun Zhao, Hui Lu, Mitra Dutta, and Michael A. Stroscio, Quantum-dot-based Aptamer Beacons for K+ Detection, IEEE Sensors Journal, 13, 1549-1553, 2013; Digital Object Identifier: 10.1109/JSEN.2012.2229387

Technical Approach • Synthesis of nanostructures • Binding biomolecules (proteins, DNA, selective-binding aptamers, antibodies) to manmade nanostructures • Modeling electrical, optical and mechanical properties of nanostructures • Experimental characterization of integrated manmade nanostructure-biological structures • Applications of manmade nanobiostructures in biomedical engineering including nanosensors as physiological state indicators, nanoelectronics, optoelectronics, and molecule detection.

Key Achievements and Future Goals • Numerous manmade nanostructures have been functionalized with biomolecules; recent work focuses on integration of luminescent quantum dots with DNA aptamers • Nanostructure-biomolecule complexes have been used to study a variety of biological structures including cells • Interactions between nanostructures with biomolecules and with biological environments have been modeled for a wide variety of systems • Ultimate goal is controlling biological systems at the nanoscale


Michael A. Stroscio, ECE and BioE, and Mitra Dutta, ECE

Problem Statement and Motivation • Use DNA and RNA Aptamers as well as Molecular Beacons for Chem/Bio Sensors • Biomedical Detectors • Detection of Pollutants and Toxins

Technical Approach • Graphene-based FET Fabrication; DNA or RNA Aptamer Sensing Element • Characterization of I-V Curves for Selective Binding of Analytes to Aptamers

• Extension to Quantum-wire Functionalized Aptamers • Extension to Quantum-wire—Aptamers for Simultaneous Detection of Multiple Analytes

Key Achievements and Future Goals • Potassium, Lead, Mercury, Cocaine, specific DNA molecules and other analytes detected; sensors designed for other biomolecules including IgE • Graphene-based and electrolyte-based nanosensors demonstrated


Bo Song, Huajun Yuan, Cynthia Jameson, Sohail Murad, Chemical Engineering Department Primary Grant Support: US Department of Energy

Problem Statement and Motivation •

Understanding the interaction between nanoparticles and biological membrane is of significant importance in applications in cell imaging, biodiagnostics and drug delivery systems.

Some basic questions explored: • How do nanoparticles transport? • What structural changes occur? • Can a lipid membrane heal?

Use molecular dynamics simulations to develop better understanding of the transport process and characterization of nanoparticles.

Investigate the elastic and dynamic properties of lipid membrane, during the permeation of the nanoparticles.

Key Achievements and Future Goals

Technical Approach • • • •

Used various sizes of nanocrystals as probes. Used coarse-grained dipalmitoylphosphatidy-lcholine (DPPC) lipid bilayers as a simple model membrane. Explored the transport of nanocrystal across DPPC lipid bilayers Investigated the changes in the structural and mechanical properties of DPPC bilayers during permeation.

• • •

Used coarse-grained models to simulate nanoparticles and biomembrane systems successfully. Examined the permeation process of nanoparticles through lipid membranes and the response of lipid membrane at the fundamental molecular level. Explored the effect on transport across a lipid membrane arising from surface coatings on the nanoparticles.


Bo Song, Huajun Yuan, Cynthia Jameson, Sohail Murad, Chemical Engineering Department Primary Grant Support: US Department of Energy

Problem Statement and Motivation •

Understanding the nanoparticle permeation mediated water/ion penetration and lipid molecule flip-flops is of significant importance in drug delivery systems and cytoxicity.

Some basic questions explored: • How many water molecules and ions may leak during nanoparticle permeation? • How do water and ion leakages depend on the physical properties of the nanoparticle and the surrounding environment? • How do individual lipid molecules respond when nanoparticle, water and ions permeate simultaneously?

Use coarse-grained molecular dynamics simulations technology.

Key Achievements and Future Goals

Technical Approach • • •

Used bare gold nanoparticles as model nanoparticles. Coarse-grained dipalmitoylphosphatidy-lcholine (DPPC) lipid bilayers were used as a simple model membrane. Investigated the effect of NP size, permeation velocity, pressure and ion concentration gradient effects.

Used coarse-grained models to simulate nanoparticles and biological membrane systems successfully.

Examined the permeation process of nanoparticles through lipid membranes at the fundamental molecular level.

Examined the water/ion penetration and lipid molecule flip-flop during the nanoparticle permeation.


Randall J. Meyer, Department of Chemical Engineering, University of Illinois at Chicago in collaboration with Dr. Jeffrey Miller, Chemical Sciences and Engineering Division, Argonne National Lab Supported by NSF grants CBET 0747646 and CBET 1067020

Problem Statement and Motivation

Industrial catalyst

Finite fossil fuel reserves dictate that new solutions must be found to reduce energy consumption and decrease carbon use

Current design of catalysts is often done through trial and error or through combinatorial methods without deep fundamental understanding

Our group seeks to combine experimental and theoretical methods to provide rational catalyst design

100 x 100 nm Model Catalyst

Computational model

Key Achievements and Future Goals

Technical Approach •

A combination of experimental methods is employed to characterize catalysts: • X-ray Absorption Spectroscopy (XAS) is used to identify local structures and to determine electronic structure changes in alloys • Scanning Transmission Electron Microscopy is used to provide structural models for catalytic active sites with atomic resolution • Kinetic analysis provides insight into reaction pathways Density Functional Theory calculations are used to determine the thermodynamics and kinetics of proposed reaction mechanisms

Graduate Student Haojuan Wei has identified novel acrolein hydrogenation catalysts based on dilute alloys

Graduate student Carolina Gomez has found that alloying effects in XAS can be classified in terms of charge transfer, lattice effects and changes in orbital overlap.

Graduate student David Childers has shown that alloy catalysts for neopentane hydrogenolysis/isomerization can be more selective than either monometallic component.


G. Ali Mansoori, Bioengineering & Chemical Engineering Primary Grant Support: ARO, KU, UMSL, ANL

Problem Statement and Motivation •

Experimental and theoretical studies of organic nanostructures derived from petroleum (Diamondoids, asphaltenes, etc.)..

Quantum and statistical mechanics of small systems - Development of ab initio models and equations of state of nanosystems. Phase transitions, fragmentations.

Molecular dynamics simulation of small systems - Studies in nonextensivity and internal pressure anomaly of nanosystems.

DNA-Dendrimers nano-cluster formation, nanoparticle-protein attachment for drug delivery

Key Achievements and Future Goals

Technical Approach •

Nanoparticles-Protein Attachmrnt

DNA-Dendrimer Nano-Cluster Electrostatics (CTNS, 2005)

Nano-Imaging (AFM & STM), Microelectrophoresis

Nonextensivity and Nonintensivity in Nanosystems - A Molecular Dynamics Sumulation J Comput & Theort Nanoscience (CTNS,2005)

Ab Initio computations (Applications of Gaussian 98)

Principles of Nanotechnology (Book) World Scientific Pub. Co (2005)

Nano-Systems Simulations (Molecular Dynamics)

Statistical Mechanical Modeling and its Application to Nanosystems Handbook of Theor & Comput Nanoscience and Nanotechnology (2005)

Nano-Thermodynamics and Statistical Mechanics •

Phase-Transition and Fragmentation in Nano-Confined Fluids J Comput & Theort Nanoscience (2005)

Interatomic Potential Models for Nanostructures" Encycl Nanoscience & Nanotechnology (2004)


Sohail Murad, Chemical Engineering Department Primary Grant Support: US National Science Foundation

Problem Statement and Motivation FAU Zeolite

MFI Zeolite

CHA Zeolite

Understand The Molecular Basis For Membrane Based Gas Separations

Explain At The Fundamental Molecular Level Why Membranes Allow Certain Gases To Permeate Faster than Others

Use This Information To Develop Strategies For Better Design Of Membrane Based Gas Separation Processes For New Applications.

y z

Zeolite Membrane x

Feed Compartment (High Pressure)

Product Compartment (Low Pressure)

Feed Compartment (High Pressure)

Recycling Regions

Key Achievements and Future Goals

Technical Approach •

Determine The Key Parameters/Properties Of The Membrane That Influence The Separation Efficiency

Explained The Molecular Basis Of Separation of N2/O2 and N2/CO2 Mixtures Using a Range of Zeolite Membranes.

Use Molecular Simulations To Model The Transport Of Gases –i.e. Diffusion or Adsorption

Used This Improved Understanding To Predict Which Membranes Would Be Effective In Separating a Given Mixture

Focus All Design Efforts On These Key Specifications To Improve The Design Of Membranes.

Used Molecular Simulation to Explain the Separation Mechanism in Zeolite Membranes.

Use Molecular Simulations As A Quick Screening Tool For Determining The Suitability Of A Membrane For A Proposed New Separation Problem


Huajun Yuan, Cynthia Jameson and Sohail Murad Primary Grant Support: National Science Foundation, Dow Chemical Company

Problem Statement and Motivation •

Needs for Better Physical Property Model

Industrial Interest – Safe Storage of Liquids at Extreme Conditions

Understand Molecular Basis For Chemical Shift in Liquids

Explain At the Fundamental Molecular Level the Close Relation Between Chemical Shift and Solute-Solvent Interaction Potential

Use This Information to Develop Strategies For Better Design of Solute-Solvent Interaction Potentials, and Provide a Better Estimation of Henry’s Constant (Solubility of Gases in Liquids)

Key Achievements and Future Goals

Technical Approach •

Use Molecular Dynamics Simulation to Model Chemical Shift of Gases in Alkanes

Determined the Key Parameters of Solute-Solvent Interaction Potential, Improved the Potential for Better Solubility Estimations.

Determine the Key Parameters of Solute-Solvent Interaction Potential.which Affect the Solubility

Calculated the Gas Solubility of Xenon in Different Alkanes at Different Temperatures. Showed that Improved Agreement with Chemical Shift Resulted In Better Solubility Results

Use Molecular Simulation for Chemical Shift Calculation as a Quick Screening Tool for Improving the Intermolecular Potential.

Able to Use Modified Potential Model to Get Better Estimations of Solubility of Gases In Liquids, Especially under Extreme Conditions Which are Difficult to Measure Experimentally.

Estimate the Solubility of Gases in Liquids using the Improved Potential Model.


Lewis E. Wedgewood, Chemical Engineering Department Primary Grant Support: National Science Foundation, 3M Company

Problem Statement and Motivation •

Construct a Theory that Allows the Vorticity to be Divided into an Objective and a Non-Objective Portion

Develop Robust Equations for the Mechanical Properties (Constitutive Equations) of Non-Newtonian Fluids using the Objective Portion of the Vorticity

Solve Flow Problems of Complex Fluids in Complex Flows such as Blood Flow, Ink Jets, Polymer Coatings, Etc.

Key Achievements and Future Goals

Technical Approach •

Mathematical Construction of Co-rotating Frames (see Figure above) to Give a Evolution for the Deformational Vorticity (Objective Portion)

Finite Difference Solution to Tangential Flow in an Eccentric Cylinder Device

Brownian Dynamics Simulations of Polymer Flow and Relation Between Polymer Dynamics and Constitutive Equations

Continuum Theory And Hindered Rotation Models To Model Mechanical Behavior

Improved Understanding Of the Modeling of Complex Fluids

Applications to Structured Fluids such as Polymer Melts, Ferromagnetic Fluids, Liquid Crystals, etc.

Development Of Constitutive Relations Suitable For Design Of New Applications

Verification Of Hindered Rotation Theory And The Transport Of Angular Momentum In Complex Fluids


Sheng-Wei Chi, Department of Civil and Materials Engineering, UIC Primary Grant Support: UIC

Problem Statement and Motivation

Progressive penetration processes and predicted damage and contact surfaces

Increasing demands are placed on materials and structures to withstand complex phenomena due to extreme loads such as impact and penetration.

Key issues needed to be addressed in penetration simulation include high strain rate, extreme large deformation, material fracture, and fragment impact.

The study aims to develop a multiscale meshfree approach for modeling fragment penetration into concrete.

The ultimate goal is to understand better the phenomena in the penetration process and to predict the structure response under extreme loads.

Comparison of experimental and numerical damage patterns

Key Achievements and Future Goals

Technical Approach • • • •

Semi-Lagrangian Reproducing Kernel Particle formulation in which the point discretization follows the material while the radius of interaction of a point is fixed in Euler coordinates. Levelset enhanced kernel contact algorithm Image-based meso-scale concrete fracture simulation Microstructure informed damage model Meshfree discretization

p

0

Schematic of image-based meso-scale concrete fracture simulation

Develop a levelset enhanced kernel contact algorithm that does not require a predefined contact surface.

Develop an image-based computational approach to effectively construct a computer model based on cross sectional images.

Develop a concrete constitutive model based on the damage evolution in the meso-scale via the energy bridge theory.

The future Goal of this study is to take into consideration multi-physics phenomena in penetration simulations, including: • • •

Thermo effects Rate effects on concrete and projectiles Shock wave


Maen Farhat, Momenur Rahman, Mustapha Ibrahim and Mohsen Issa, Univeristy of Illinois at Chicago Primary Grant Support: Utility Concrete Products (UCP)

Problem Statement and Motivation •

Key Achievements and Future Goals

Technical Approach •

• •

Perform experimental study on a 20 ft. high, 166 in. wide full scale prototype (TPCCRW) to asses the strength and service behavior of the wall: Identify the optimum methods and stages of fabrication and prepare an advanced instrumentation and monitoring system that will allow to examine the behavior of the wall at different locations. The TPCCRW was tested experimentally by soil backfilling to simulate real life applications followed by applying load scenarios (4 different tests) reaching 200 kips by using hydraulic actuators. Conduct a finite element analysis using ANSYS package. The nonlinear analysis is carried out imitating the exact construction sequence of a retaining-wall backfills and surcharge loads.

Totally Precast Concrete Counterfort Retaining Wall (TPCCRW) system is an innovative solution to the growing need to develop sustainable retaining wall systems. It provides means for fast track construction that would significantly cut off the time of the construction and erection processes. It is designed to satisfy the code requirements for strength, serviceability, durability and constructability within the least possible cost and the maximum possible safety margins. The fully precast retaining wall system consisted of the face panel and 3 counterforts fabricated as a single entity and assembled with the precast base slab. From each counterfort, 5 headed anchors were extended and grouted in the base slab.

• • •

• • •

The anchors, being the most critical component, succeeded to maintain serviceability, and ultimate strength requirements per AASHTO LRFD. The wall deflection in the middle (H/2) did not exceed 0.2 in. and did not exceed the allowable limits. An accurate finite element model capable of predicting the performance of TPCCRW was calibrated with the acquired experimental data using ANSYS software. A comprehensive design for the TPCCRW meeting the requirements of AASHTO LRFD was performed. Future parametric study using the validated finite element model. Additional experimental Investigation of the performance of the headed anchors when subjected to pullout load.


Ibrahim Lotfy, Maen Farhat and Mohsen Issa, Univeristy of Illinois at Chicago Primary Grant Support: NURail Center (U.S. DOT-RITA)

Problem Statement and Motivation •

• 13,000

Ultimate Pullout Load, lbs

12,000 11,000 10,000 9,000 8,000 7,000

6,000 Setup A

Setup B Setup C Setup Type

Setup D

0.5

1 2 Stroke (in./min)

73oF 100oF 125oF Temperature (oF)

Key Achievements and Future Goals

Technical Approach Striving to assess the feasibility of implementing HDPE crossties in rail applications, this study examined the behavior of the fastening system. I. Perform experimental testing as per AREMA specifications: • Investigate the behavior of the fastening system components of HDPE crossties under different loading, temperatures and setup conditions (spike pullout, spike lateral resistance and fastener uplift).

II. Conduct a finite element analysis using ANSYS: • Develop a modelling technique capable of properly simulating the interactions between each component in the system along with its effect on the HDPE crosstie.

High Density Polyethylene (HDPE) is a green, recyclable, and environmental friendly material. It has structural and economical advantages which grant it a competitive edge among other alternatives in the rail market such as wooden and concrete crossties The implementation of the new recycled Plastic railroad crossties would improve the railroad industry public image as a green, sustainable industry. The recycled products are manufactured with plastic waste that otherwise would be landfilled which reduces the waste products and additionally eliminates any pollution or deforestation. Moreover, Recycled, HDPE crossties are light, workable, easy to transport and handle, can overcome the main issues facing other materials and can replace wooden crossties on a one-to-one basis without the need for special installation or heavy equipment.

• • •

The fastening system components satisfied and surpassed the AREMA requirements for polymer composite crossties in terms of fastener uplift and spike pullout and lateral restraint. An accurate finite element model capable of predicting the performance of each component was constructed and calibrated with the acquired experimental data using ANSYS software. Experimental Investigation of the performance of the crosstie and fastening system when subjected to cyclic loading and wear/abrasion. Further optimization and calibration of the material model. Implementation of the HDPE crossties in elevated structure-bridge applications as well as assessment the track bridge interactions.

Secondary Supporters: Tangent Technologies and the Chicago Transit Authority


Ibrahim Lotfy, Maen Farhat and Mohsen Issa, Univeristy of Illinois at Chicago Primary Grant Support: NURail Center (U.S. DOT-RITA)

Problem Statement and Motivation •

• 4,000 3,500 3,000

STRESS, psi

2,500 2,000 1,500

10 F 40 F 73 F 100 F 125 F

1,000

500 0 0.00

0.01

0.02 0.03 0.04 STRAIN, in./in.

0.05

0.06

Key Achievements and Future Goals

Technical Approach Striving to assess the feasibility of implementing HDPE crossties in rail applications, this study examines its flexural behavior. I. Perform experimental testing as per AREMA specifications: • Investigate the flexural behavior, cracking and failure modes of HDPE Crossties under different conditions; center and rail seat bending. • Assess the effect of temperature changes on the flexural and mechanical properties of the HDPE crossties. II. Conduct a finite element analysis using ANSYS: • Construct a calibrated non-linear material model for use in subsequent analyses. • Develop a suitable modelling technique which portrays the actual behavior of the crosstie.

High Density Polyethylene (HDPE) is a green, recyclable, and environmental friendly material. It has structural and economical advantages which grant it a competitive edge among other alternatives in the rail market such as wooden and concrete crossties The implementation of the new recycled Plastic railroad crossties would improve the railroad industry public image as a green, sustainable industry. The recycled products are manufactured with plastic waste that otherwise would be landfilled which reduces the waste products and additionally eliminates any pollution or deforestation. Moreover, Recycled, HDPE crossties are light, workable, easy to transport and handle, can overcome the main issues facing other materials and can replace wooden crossties on a one-to-one basis without the need for special installation or heavy equipment.

• • •

The HDPE crossties satisfied and surpassed the AREMA requirements for polymer composite crossties in terms of flexural strength and stiffness (MOE and MOR). An accurate material model capable of predicting the flexural performance of HDPE crossties was constructed and calibrated with the acquired experimental data using ANSYS finite element package. Experimental Investigation of the performance of the crosstie and fastening system when subjected to cyclic loading and wear/abrasion. Further optimization and calibration of the material model. Implementation of the HDPE crossties in elevated structure-bridge applications as well as assessment the track bridge interactions.

Secondary Supporters: Tangent Technologies and the Chicago Transit Authority


Aiman Shibli and Mohsen Issa, University of Illinois at Chicago

Problem Statement and Motivation 9 8 7 6 5 4 3 2 1 0

Shear Test:

#1 #2 #3 #4 #5

0

5

10 Tensile strain

15

Spc-1 [14 days curing] Spc-2 [14 days curing]

0.5

1

1.5

2

Strain

Ball Drop :

Accelerometer

PC Supporting pin

Supporting pin

Supporting pin

Strain Gauges

Strain Gauges

0.01

Sim - Gauge - Top Sim - Gauge - Bot Test - Gauge - Bot Test - Gauge - Top

Big Plate: 70mmX20mmX1mm Small Plate: 20mmX20mmX1mm Adhesive: 70mmX20mmX0.2mm Top Span: 35mm Bottom Span: 60mm

Supporting pin

Test - Gauge - Top Sim - Gauge Bot

0.006

Sim - Gauge Top

0.004 50

Test - Gauge - Bot

0.008

100

150

200

250

Strain

Strain

0.01 0.008 0.006 0.004 0.002 0 -0.002 0 -0.004 -0.006 -0.008 -0.01

Spc-3 [7 days curing]

0

20

Loading pins

Four Point Bending:

9 8 7 6 5 4 3 2 1 0

Stress [Mpa]

Tensile stress [MPa]

Tensile Test:

0.002 0 -0.002

Force [N]

0

0.002

-0.004

0.004

0.006

Time (sec)

Key Achievements and Future Goals

Technical Approach • • •

Fiber-reinforced polymer (FRP) composites are increasingly used in structural applications due to their advantageous material properties. However, structural FRP components are difficult to connect using the traditional joining methods such bolting and riveting due to the brittle fibrous and anisotropic nature of the materials. Many structural industries have seen the use of adhesive for joining load-bearing components as an excellent candidate for replacing the traditional joining due to their unique characteristics such: high strength, light weight, dimensional stability, high joint efficiency and ease of use. In order to utilize adhesives bonding in civil infrastructure applications, it is crucial to understand their behavior and strength and to be able to predict it for a given geometries and loads.

Characterize adhesive’s mechanical property under tensile and shear loadings, at low and high rates (static and dynamic). Build representative material model that can mimic their behavior and can be used in numerical models for computational studies. Validate material model experimentally and computationally at coupon level and sub-system level at quasi-static and dynamic loadings.

• •

Quasi-static and dynamic experiments were completed on structural adhesive at different loading modes: tension and shear. Material model has been created and validated at coupon level and subsystem level, under quasi-static and dynamic loadings. Comparison between experimental results and numerical results obtained from 3D finite element analysis showed very good correlation at different loading modes and rates. Future work, this study need to be implemented and investigated in real case application


Mustapha Ibrahim, Mohsen Issa, PhD, and Mustafa Al-Obaidi, Univeristy of Illinois at Chicago Primary Grant Support: Illinois Department of Transportation (IDOT)

Problem Statement and Motivation • •

Cement production account for more than 5% of CO2 emission worldwide. On average, each ton of cement produced from a cement plant accounts for 0.92 tons of CO2 emissions. Reducing this carbon emission requires a breakthrough technology that might take decades to be adopted by the cement industry. One of the low-cost successful methods that aided in developing a more sustainable production program was in adding pulverized limestone and other inorganic processing to cement, reducing the amount of clinker in its production. IDOT is making several changes to concrete mix designs by applying revisions to cement specification. These proposed revisions will enable the use of more limestone and inorganic processing additions (IPA) (sustainable materials) for concrete pavements, overlays, and bridge decks. A study was conducted to test the performance of concrete mixes batched with cement comprising of higher quantities of limestone and IPA.

Key Achievements and Future Goals

Technical Approach • •

The goal is to develop economical and practical concrete mixes that would provide sustainable and durable concrete pavements. Twenty-four concrete mixes with different cementitious combinations and aggregates were developed for this study. Three sources of cement were used. The mix combination of each cement source is shown below: • The program included testing the fresh and hardened strength and durability properties of concrete. • The fresh properties included measuring the slump, air content, unit weight, and setting time. The strength properties included testing the compressive and flexural strength of concrete. The durability properties included testing the Freeze and thaw resistance and rapid dynamic modulus of concrete, microscopic hardened entrained air, rapid chloride penetration resistance, salt ponding and chloride ion penetration, and water permeability.

• • •

The use of limestone and IPA in cement with quantities above the specified limits proved to have similar performance to conventional cement when mixed in concrete. The use of different cementitious materials (Fly Ash or Slag) improved the durability of concrete The success of this project prompted the IDOT to adopt the use of the new modified cement in replacement to the conventional cement. The amount of cement used in concrete batching was 375 lbs/yd3 which is the minimum cement content required by IDOT. As a result of this study, the amount of cement was increased from 375 lbs/yd3 to 400 lbs/yd3. Future development of concrete service life predictions and models to study the chloride ingress/ diffusion in concrete and its resistance to freeze and thaw.


Hossain Saboonchi, PhD Student and Didem Ozevin, Assistant Professor Department of Civil and Materials Engineering Primary Grant Support: UIC, Faculty Research Award Out of plane AE sensor (fn=50 kHz)

Problem Statement and Motivation

Out of plane AE sensor (fn=200 kHz)

In plane Inertia Switch (fn=150 Hz) Out of plane Inertia Switch (fn=100 Hz) Strain Sensors (120 Ω & 350 Ω)

Capacitance change

In plane AE sensor–gap change (fn=150 kHz)

SEM image of MEMS strain sensor

In plane AE sensor–area change (fn=100 kHz)

dC d dA dg    Co  A g

• Acoustic Emission is a highly sensitive Structural Health Monitoring method to monitor damage in aging structures. However, the sensitivity to environmental noise requires significant post-processing to differentiate the relevant data. • Single SHM method may not be sufficient for reliable damage detection and diagnostics. Multiple information collection simultaneously reduces the uncertainty.

SEM image of In plane AE sensor–gap change (fn=150 kHz)

Technical Approach • Multiple sensing elements are designed on the same device, including acoustic emission sensor to measure motions in out-of-plane and in-plane, strain and vibration to be used as inertia switch to activate AE collection. • The response of in-plane sensor to the out-of-plane motion is eliminated through novel differential mode approach. • The AE sensor is connected to on-chip inertia switch in order to collect AE data when the structure is highly stressed. The hypothesis is that the crack grows when the structure is loaded above a certain level.

• MEMS allow manufacturing multiple sensing mechanisms on the same device.

Key Achievements and Future Goals • The MEMS sensors are designed, modeled using COMSOL Multiphysics software and manufactured using MetalMUMPS process.

MEMS AE sensor

• The electrical and mechanical characterizations are completed. • The device will be tested in laboratory for detecting crack initiation and growth.

MEMS strain sensor


Didem Ozevin, Assistant Professor, Zahra Heidary PhD Student, Nadia Simek Undergraduate Student Department of Civil and Materials Engineering Primary Grant Support: NSF

Problem Statement and Motivation

single point leak localization

• The buried and on-ground pipelines develop damage due to temporal variables such as corrosion and creep or instantaneous threats such as earthquake and impact.

New Approach with Particular Geometry Sensor Design

• The detection of leaking at oil, water or natural gas pipelines before reaching structural instability can increase the public safety and prevent environmental pollution. • Passive nature of Acoustic Emission implemented for real time leak detection.

method

can

be

• The challenge is that the sensor sensitivity and wave attenuation prevent a reasonable sensor spacing for pipeline networks.

Technical Approach • The numerical models are linked with experimental studies to understand the reliable leak detection range and sensor spacing. The waveform properties of leaks due to different operational conditions can be identified experimentally. • Shear type Acoustic Emission sensor increases the sensor spacing range due to less attenuative characteristics of longitudinal waves. • Highly efficient numerical formulation is developed to study wave propagation in pipes due to non-axisymmetric loading. • Wave characteristics due to different leak rates for different frequencies are investigated.

Key Achievements and Future Goals • The AE characteristics due to varying pipe pressure, leak size and earth pressure are identified. Numerical attenuation curves are driven. • The AE sensor is designed with a particular geometry, modeled numerically and manufactured. • The developed transducer and the numerical model will be tested in a field condition.

Comparison of 2D efficient model with conventional 3D models


Didem Ozevin, Assistant Professor and Zeynab Abbasi PhD Student Department of Civil and Materials Engineering Primary Grant Support: TRB IDEA and NSF

Problem Statement and Motivation Complex loading case

Wave change with stress

Laboratory calibration for biaxial loading for existing equation as

Technical Approach • The research objective of this proposal is to understand the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded critical structural components in order to measure the stress state at a given cross section. • The goal is to quantify the normal stresses and shear stress at a given cross section, which will be achieved through testing a set of frequencies to create Rayleigh waves with varying depth of penetration. • The equation in the literature will be modified to introduce the effect of shear stress on nonlinear ultrasonic measurement as

Dv = K1s 1 + K 2s 2 + K3s 12 vo

• Understanding the risk for a built structural element requires knowledge of the cumulative stress state in order to estimate the remaining strength such as residual stress and excessive loading condition. • A reliable damage prognostic approach should have a welldefined damage accumulation function. • The quantification of the cumulative stress state for a built element is needed for preventing unexpected failures at highrisk structural elements. • Currently, there is no nondestructive testing method to find stress tensor including normal and shear stresses.

Key Achievements and Future Goals • Multi-scale bridge model is built to estimate stresses at a 3/8 inch thick gusset plate. • An ultrasonic measurement device to quantify the stress at three directions is built.

• The measurements from laboratory scale plate will be conducted and theoretical equations will be modified to include the shear stress.


Eduard Karpov, CME Primary Grant Support: National Science Foundation

Problem Statement and Motivation •

• •

• • Typical deterministic multiscale modeling approach; Broughton, PRB 60(4)

Creep cavity in 304 austenitic steel, and its self-healing mechanism by BN surface precipitation; Shinya, IJMSS 17

Key Achievements and Future Goals

Technical Approach •

Continuum scale finite element model reflects the concurrent atomistic configuration via frequently updated material properties, while the kinetic Monte-Carlo model utilizes deformation parameters for an update of interatomic geometry and microscopic diffusion rates

Modern functional materials for engineering and medical applications are designed to perform a self-controlled smart action, similar to a living creature able to sense and process the environment and take necessary actions Self-healing materials is one important class of evolutionary smart materials The smart action is related to a progressive change of constitutive material properties at a macroscopic interval of time, governed by atomic scale processes Interplay between the mechanical performance and the internal structure dynamics can be two-way Deterministic multiscale modeling approaches with an atomistic resolution based on molecular dynamics are inadequate in application to the evolutionary materials, due to physical time limitations

• • •

An efficient mechanokinetic coupling methodology has been developed and applied to the to biomimetic crack self-healing by surface precipitation under external mechanical loading Physical time is derived statistically from temporal characteristics of small scale processes to enable modeling over macroscopic intervals of physical time with an atomistic resolution Qualitative trends of the self-healing problem are compliant with experimental observations, while the modeling takes the analysis far beyond available empirical data and current experimental capabilities The proposed methodology is applicable to a wide class of evolutionary processes including strain dependant diffusion, nanostructure synthesis, material chemical transformations, surface chemical waves and adsorbate dynamics


Eduard Karpov, CME Primary Grant Support: National Science Foundation

Problem Statement and Motivation • •

• • Hot electron mechanism of electrolyte-free chemical to electrical energy conversion; Karpov et al., APL 94, 214101

Key Achievements and Future Goals

Technical Approach • •

Electric charge separation and the resultant electromotive force can be achieved in electrically continuous metal-semiconductor catalytic structures with nanometer thickness metallization (diagram above) Metal nanofilm thickness must be smaller than the hot electron mean free path that is 10-50 nm for most catalytic metals Laboratory system setup for hot electron current detection: (1) vacuum/gas handling components (2) mass spectrometer (3) signal conditioning unit (4) multichannel temperature controller (5) analytical chamber (6) main flange for sample mounting (7) high precision V/A source

Traditional fuel cell technologies based on ground-state electrochemistry suffer from slow-rate ionic diffusion, spurious electronic conduction in electrolytes and electrolyte degradation At the same time, synergistic catalytic effects observed in composite catalysts, in particular, in photocatalysts with a nanodispersed metal phase is surprising. Evidence exists that it owes to an exchange of inequilibrium charge carriers (hot electrons) at the metal/nonmetal support interface Reaction induced hot electron flow in a class of electrically continuous metal-semiconductor catalytic nanostructures provide a hope for “electrolyte-free chemical to electrical energy conversion” Hot electron currents detected in metal-semiconductor nanostructures also provide a valuable in-situ analytical tool to study basic physical mechanisms of heterogeneous catalysis

• •

• •

Studies of Pd/SiC, Pd/GaP and Pt/GaP prototypes revealed the hot electron component to comprise 60-85% of the total current induced by the H2+1/2O2 = H2O surface reaction, and the remaining fraction belongs to the usual thermal currents Reliable techniques to separate the hot electron and thermal currents have been developed Electron yield of a potential electrical generator was 0.20 for the SiCand 0.11 for GaP-based prototypes, implying a big promise for this electrolyte-free chemical-electrical energy conversion approach The hot electron current was also demonstrated for identification of distinct modes of the surface reaction Higher efficiency material systems operating at room temperature are currently underway


J.E. Indacochea, M.L. Wang, Department of Civil and Materials Engineering, UIC H.H. Wang, Materials Science Division, Argonne National Laboratory Primary Grant Support: National Science Foundation AAO nanowell

Problem Statement and Motivation Pd nanoparticle

0.735

Al substrate

H off

1% H

0.734

Hydrogen has been envisioned as a futuristic energy system. Gas detectors will be key components to ensure safety and reliability in hydrogen infrastructure.

Limitations of current hydrogen sensing devices include long response time, low sensitivity, and poor performance at room temperature.

Very large active surface and nanoscale dimensions make nanostructures a promising alternative to overcome current limitations in hydrogen detectors.

Resistance (kOhm)

0.733 0.5% H

0.732 0.3% H 0.2% H

0.731

0.1% H

0.73

0.05% H

H on

0.729 0.728 0.727 0

20

40

60

80

100

120

140

160

Time (s)

Change in resistance in presence of hydrogen at different concentrations

Key Achievements and Future Goals

Technical Approach •

Anodic aluminum oxide (AAO) nanowell array has been selected as substrate because it provides a robust, insulating, and ordered structure for catalyst deposition.

Pd nanoparticles have been selected as catalyst due to their high sensitivity and selectivity to react with hydrogen.

The nanostructure is being characterized and tested for hydrogen detection. Dimensions and configuration are being systematically studied to achieve optimal performance.

The electrical resistance of the nanostructure increases with hydrogen concentration due to the formation of a non conductive Pd hydride phase.

Response time is greatly faster compared to that for other nanostructured and micro sensing devices.

Very low hydrogen concentrations can be detected at room temperature without compromising sensitivity.

The main goal is to achieve optimal performance and integrate the nanostructure into modern sensors.


Michael McNallan, Civil and Materials Engineering, UIC; Ali Erdemir, Argonne National Laboratory Primary Grant Support: U.S. Department of Energy 752

400

Mechanical Seals and bearings fail due to frictional heating and wear

Materials used are hard ceramics, such as SiC or WC

Friction can be reduced by coating with carbon as graphite or diamond

Graphitic coatings are not wear resistant

Diamond coatings are wear resistant, but fail by spallation or delamination from the underlying ceramic

572

max. safe temperature

M A X . S A F E T EM P . F O R HNBR

SiC-SiC

200

392

SiC-CDC 100

°F

S T AT O R O .D . T E M P . °C

300

Problem Statement and Motivation

212

0 0

60

120

180

240

300

360

420

480

540

600

660

720

780

840

900

T IM E (S )

Pump seal face temperature during dry running at 4000 rpm with and without CDC coating

Key Achievements and Future Goals

Technical Approach •

Produce a low friction carbon layer by chemical conversion of the surface of the carbide

SiC(s) + 2Cl2(g)  SiCl4(g) + C(s)

At temperatures < 1000oC, carbon cannot relax into equilibrium graphitic state and remains as Carbide Derived Carbon (CDC)

CDC coating contains nano-porous amorphous C, fullerenes, and nanocrystalline diamond

CDC is low friction, wear resistant, and resistant to spallation and delamination

CDC has been produced in the laboratory

It’s structure and conversion kinetics have been characterized

Tribological performance was verified in laboratory and industrial scale pump tests with water

CDC was patented and selected for an R&D 100 Award in 2003

CDC was Licensed to Carbide Derivative Technologies, Inc.in 2006

Scale up to industrial production rates, characterization of process reliability and testing in specific industrial environments is the next goal.


Investigators: Mitra Dutta, ECE; Michael Stroscio, ECE, BioE, Physics Primary Grant Support: AFSGO

Problem Statement and Motivation •

Mercury ions and other heavy metals are found in environmental waters, which can lead to toxicity in humans

A rapid detection method for environmental monitoring and exposure levels in humans is needed

Engineering a nanoconstruct to detect these heavy metals in fluids can be done using quantum dots and single stranded DNA

Hg 2+ 10000

: eFluor® 650NC

: DNA aptamer

Intensity (a. u.)

: Nanogold : Hg 2+

0 Hg

5000

500 nM Hg 824 mM Hg

0 600

650

700

Wavelength (nm)

Key Achievements and Future Goals

Technical Approach •

DNA aptamers used as molecular recognition elements in sensing strategies for ions and biomolecules

Mercury ions were detected using a spectrometer to measure the fluorescence intensity of the QD

Aptamers can perform like antibodies with affinity to a wide range of targets which can result in a conformational change as in the figure

Detection is achieved in the nanomolar range, while higher levels of mercury were shown to interfere with QD fluorescence

Quantum dots (QD) are robust and stable fluorophores and gold nanoparticles are stable quenchers

Future targets include lead, zinc, and cadmium, which have been shown to interact with specific DNA aptamers

Conjugating QDs and gold nanoparticles to aptamers provides the detection signal

Optical detection platform to be applied to biomarkers

Translate detection assay to portable handheld device

Surface energy transfer between QD and gold nanoparticle is the mechanism for optical detection


Investigators: M. Dutta, ECE, M. Stroscio, ECE and BioE Primary Grant Support: AFOSR, ARO, NSF, SRC, DARPA, DHS Quantum Dots in MEH-PPV Polymer

Problem Statement and Motivation

Gold contacts •

Design, fabrication, characterization of QD-based photon-absorbing media embedded in conductive polymers for optoelectronic devices

For underlying concepts see group’s paper on “Applications of Colloidal Quantum Dots,” Microelectronics Journal, 40, 644-649 (2009).

ITO Glass

Top view MEH-PPV Polymer / CdSe Quantum Dot Composite

Key Achievements and Future Goals

Technical Approach •

Design of quantum-dot (QD) ensembles in conductive polymers

Fabricating quantum-dot (QD) ensembles in conductive polymers

Modeling electrical and optical properties including robustness and sensitivity to QD-QD separation

Experimental characterization of integrated structures

Multi-wavelength optoelectronics

Numerous simulations of electrical and optical properties including robustness and sensitivity to QD-QD separation

Numerous simulations for a variety of QD—conductive-polymer systems

Current sensing AFM measurements of I-V curves for a variety of QDs embedded in conducting polymers

Ultimate goal is realization of multi-wavelength photodetectors


P.I. Igor Paprotny Funding: new faculty startup, California Energy Commission

Problem Statement and Motivation • • •

Integrating discrete components on flexible substrates Using ultra low-power wireless radios and microcontrollers to implement low-power wireless networks Algorithms reconstruct system parameters from sparse (distributed) sensory data

Energy harvesting enables potentially perpetual operation of the sensor nodes

Key Achievements and Future Goals

Technical Approach • •

Low-power radios and ancillary electronics introduce the possibility of ubiquitous low-cost wireless sensor networks. Distributed sensors are predicted to be an integral part of our every day life Enable many important applications: • Energy systems sensing • Body sensor networks • Environment systems

• • •

Created a 4 mm x 4 mm sized low-power sensor node using discrete components Developed a self-calibrating current sensor system Future goals: • Develop a co-location system for 1 mm3 wireless sensor node • Integrate a wireless sensor network in underground coal mines • Create a smart bandaid body sensor node


Wenjing Rao, ECE department

Problem Statement and Motivation

Post-manufacturing defect-tolerant logic implementation on nano-crossbars • Models, algorithms, yield analysis

Exploiting time / hardware / information redundancy at multiple design hierarchical levels and granularities • Logic gate level: nano-PLAs • Arithmetic level: fault tolerant adders • Processor architecture level: speculative computation based fault tolerance paradigm

Redundancy sharing on a locally connected network • Flexible, dynamic assignment schemes • Network analysis

Future electronic systems on nanoscale devices

Promises • Boosts of computational power • Wide application domains

Challenges • Severe unreliability (manufacturing defects + run time faults) • Localized interconnect

Need: • New system design and computational paradigms for constructing future reliable nanoelectronic systems.

Key Achievements and Future Goals

Technical Approach •

Low-cost defect / fault tolerance approaches exploiting • Reconfigurability • Multiple hierarchical levels and granularities • Regularity

Decentralized resource allocation protocol on locally connected network • Low communication overhead • Scalable • Generalizable framework for self-adaptive systems


P.I. Igor Paprotny Funding: new faculty startup, Intel, DOE

Problem Statement and Motivation • • •

Airborne particulate matter (PM) is harmful to our health In particular fine PM smaller than 2.5 µm in diameter (PM2.5) Includes: • Diesel exhaust • Tobacco smoke • Bio-aerosols

• •

Current instruments are too big and expensive to be portable Personal PM2.5 sensor does not exist

Key Achievements and Future Goals

Technical Approach • • •

Use MEMS techniques to create air-microfluidic lab-on-a-chip that measures airborne PM by direct mass deposition Inertial separation (virtual impaction) is used to separate PM2.5 from the rest of the airstream. Thermophoretic precipitation is used to deposit the separated PM2.5 on top of a mass-sensitive film-bulk acoustic resonator (FBAR) The rate of the frequency shift in the FBAR corresponds to the PM2.5 concentration.

• • • •

Demonstrated a microfabricated PM2.5 direct-mass sensor • 5 cm x 2.5 cm x 1 cm in size Sensitivity comparable to large instruments • 1-2 µg/m3 PM2.5 concentration Form factor enables integration into a regular cellphone Future goals: • Improve sensitivity • Measure particle-size distribution • Chemical speciation


P.I. Igor Paprotny Funding: Department of Health and Human Services

Problem Statement and Motivation • • • •

Key Achievements and Future Goals

Technical Approach • • • •

A flat surface placed in a mine environment collects deposited dust Incident light at several wave-lengths is reflected from the deposited layer, and is collected by a photo-detector Microfabricated mass sensors and humidity sensors helps to determine the true explosibility of the deposited layers Connects to a communication backbone to automate the operation of the rock dusting equipment

Excessive build-up of coal dust in underground mines leads to explosion risk Rock-dusting (dispensing of inert lime-stone dust) is used to mitigate the explosion risk • Increasing total incombustible content (TIC) Currently manual sampling of dust in mines to determine TIC and control rock dusting A low-cost reliable automated method is needed

• • •

Verified the viability of using multi-wavelength optical method to detected the layers of deposited dust Created preliminary sensor prototype Future goals: • Determine the dependence of the optical method on humidity content and particle size, as well as the layer thickness • Create a MEMS mass and humidity sensor • Integrate with a communication backbone in the underground mine


Investigators: M. Dutta, ECE, and M. Stroscio, ECE and BioE

Problem Statement and Motivation

Bare QDs

FRET

• Organic-inorganic hybrid structures enable integration of useful organic and inorganic characteristics for novel optoelectronic applications. • The time required for resonant energy transfer in the composite of inorganic quantum dots (QDs) and photosystem I (PS-I) has not been determined previously. Transfer time ~ 6 ps).

Colloidal Quantum Dots and Photosystem-I Composite

Technical Approach • Synthesis of the composite of inorganic CdSe QDs and organic PS-I, hexahistadine-tagged PS-I from Chalamydomonas reinhardtii - green unicellular algea • Experimental measurement of the energy transfer between QDs and PS-I • Investigation of structural, optical and transport properties by means of photoluminescence, time-resolved photoluminescence, absorption, capacitance-voltage and I-V measurements

Key Achievements and Future Goals • Observed energy transfer from CdSe QDs to PS-I by optical and electrical measurements. • Photoluminescence data and absorption data show that the energy of excited carriers of CdSe QDs to PS-I by processes that include fluorescent resonant energy transfer (FRET) between the inorganic and organic components of the system. • I-V measurement data are sensitive to incident light in the composite CdSe QDs/PS-I material.


Investigators: ; M. Dutta, ECE, and M. Stroscio, ECE and BioE

Problem Statement and Motivation • Design, fabrication, characterization of QD-based nanosensors on a variety of platforms • For underlying concepts see group’s paper on “Applications of Colloidal Quantum Dots,” Microelectronics Journal, 40, 644-649 (2009).

Technical Approach • Design of quantum-dot (QD) based nanosensors

Key Achievements and Future Goals • Numerous demonstration of nanosensors based on beacon like structures

• Fabricating quantum-dot (QD) ensembles • Modeling electrical and optical properties including robustness and sensitivity to QD-QD separation

• Numerous nanosensors demonstarted for a variety of QD systems

• QD blinking modeled and observed • Experimental characterization of integrated structures • Multi-analyte detection

• Ultimate goal is realization of multi-analyte detectors on a single platform


P.I. Igor Paprotny Funding: new faculty startup

Problem Statement and Motivation • • • •

200 mm •

Key Achievements and Future Goals

Technical Approach • • •

• •

Use MEMS techniques to create robotic chassis several micrometers in size A stress-engineering post processing solution adds precisely controlled curvature to planar silicon structures Power is provided externally through a set of underlying interdigitated electrodes to the propulsion component, which is a scratch drive actuator (electrostatic inchworm) Patterned stress-engineering layer defines the out-of-plane deflection of the steering arms Difference in deflection results in different control voltage, which can be used to independently control several microrobots

New, largely unexplored area of robotics Difficult to achieve due to component scaling Microelectromechanical systems (MEMS) Components difficult to implement at the microscale: • On-board power • Sensing • On-board control Many application opportunities, such as in: • Medicine, • Manufacturing • Information security

• • • •

Demonstrated independent control of several (four) MEMS microrobots Controlled self-assembly of microscale structures Developed a new stress-engineering process to design the robots that does not require a photo lithography stage Future goals: • Develop designs and algorithms that allow for simultaneous control of large numbers of microrobots • Create new microrobotic systems that operate in liquids • Use 2-photon stereolithography to create new types of microrobotic systems


Mitra Dutta, ECE and Michael Stroscio, ECE & BioE Primary Grant Support: ARO, AFOSR (a) 0 1 2

-4

Fluorescence

-3 LUMO

3 4 5 6 7

HOMO

Organic-inorganic hybrid structures enable integration of useful organic and inorganic characteristics for novel applications such as solar cell, chemical sensors, and fluorescent biotags.

Energy transfer in the composite of inorganic quantum dots (QDs) and photosystem I (PS-I) is not understood although it is very important and well studied for photosynthesis.

0 +1

+- +-

+2 CdSe QDs

QDs

-2 -1

En1 Ec hv Ev Eh1

8

Problem Statement and Motivation

NEH(V)

Evac(eV)

+3

PS-I

QDs+PS1

Glass

Glass

Key Achievements and Future Goals

Technical Approach •

Synthesis of the composite of inorganic CdSe QDs and organic PS-I

Observed energy transfer from CdSe QDs to PS-I by optical and electrical measurements.

Experimental measurement of the energy transfer between QDs and PS-I

Photoluminescence data and absorption data show that the energy of excited carriers of CdSe QDs to PS-I by means of radiative emission, FRET, and electron/hole transfer between the inorganic-organic system.

I-V measurement data are sensitive to incident light in the composite CdSe QDs/PS-I material.

Further studies continue to identify each energy transfer method.

Investigation of structural, optical and transport properties by means of photoluminescence, time-resolved photoluminescence, absorption, capacitance-voltage and current-voltage measurements


Investigators: ; M. Dutta, ECE M. Stroscio, ECE and BioE

Problem Statement and Motivation Example of ZnO Nanowires

• Design, fabrication, and characterization of quantum-wire based optoelectronic devices and structures including those incorporating conductive polymers • Design, fabrication, and characterization of quantum-wire based piezoelectric devices and structures for energy harvesting

Technical Approach • Growth of quantum wires

Key Achievements and Future Goals • Numerous simulations of electrical, optical and piezoelectric properties of quantum-wire structures

• Fabrication of quantum-wire based devices • Modeling electrical and optical properties including robustness of quantum-wire-based devices

• Numerous simulations and predictions for a variety of quantum-wire—conductive-polymer structures and piezoelectric structures

• Experimental characterization of integrated structures quantum-wire-based structures

• Demonstrated polarization-dependent light inteactions with arrays of quantum wires • Strong Enhancement of Near-BandEdge PLof ZnO Nanowires


M. Dutta, ECE; M. Stroscio,ECE and BioE Primary Grant Support: ARO, NSF, AFOSR, SRC, DARPA

Problem Statement and Motivation Au wire

CdS

CdSe-ZnS

Future electronic and optoelectronic systems must be integrated on the terascale and beyond

This research effort explores the use of biomolecules as molecular interconnects for such terascale systems

CdSe-ZnS-GGGC

Key Achievements and Future Goals

Technical Approach •

Synthesis of semiconductor nanostructures

Chemical self-assembly of semiconductor nanostructures

Modeling electrical, optical and mechanical properties of ensembles of nanostructures

Experimental characterization of massively integrated networks of semiconductor nanostructures

Numerous manmade semiconducting nanostructures have been synthesized

Integrated semiconductor quantum dots have been assembled chemically in the Nanoengineering Research Laboratory at UIC

Interactions between semiconductor nanostructures and molecular wires have been modeled for a wide variety of systems

Ultimate goal is massive integration of semiconductor nanostructures in functional electronic and optoelectronic networks


Mitra Dutta, ECE. Primary Grant Support: NASA Ames Research Center

Problem Statement and Motivation •

Annealing at specific conditions and environment would refresh the Tin Oxide nanowire used in gas sensing applications.

Minimization of defects in nanowires which determine the electrical and optical properties for high performance applications.

Key Achievements and Future Goals

Technical Approach •

Synthesis of Tin Oxide nanowires using a special carbothermal reduction process.

Identifying various inherent structural defects in nanowires and understanding their role in modifying the electronic and optical properties using various experimental characterization techniques.

Obtain a specific Annealing condition which would serve to minimize the defects as well pre-charge/refresh the nanowires for future gas sensing applications.

Nanowires of various diameters have been synthesized in large scale.

Intrinsic defect levels/states/traps have been identified and minimized by annealing in oxygen and nitrogen under specific conditions. Luminescence and structural properties of the wires have improved/changed by a significant extent post annealing.

Specific annealing condition used for refreshing nanowires has been obtained.

Ultimate goal is massive integration of tin oxide nanowires for gas sensing and nuclear radiation detection.


Mitra Dutta, ECE Primary Grant Support: Intelligent Expitaxy Technology and MDA

[011] [011] aAs 1mm G

GaAs 150nm

Robust low cost Infrared photodetectors as well as those with room or near room temperature operation

Quantum well infrared photodetectors (QWIPs) due to the well developed mature GaAs technology

High-pass filter for the photocurrent which blocks the tunneling dark current

[100]

s 0.79A l0.21Ga 5nm A 0.9As In0.1Ga 3.5nm a0.79As Al0.21G 50nm

Quantum Well Infrared Photodectetor (QWIP) with a energy filter between base and collector

Problem Statement and Motivation

d grade filter 40nm a0.79As Al0.21G

Key Achievements and Future Goals

Technical Approach •

InxGa1-xAs/AlyGa1-yAs multi quantum wells, three terminal structure grown by molecular beam epitaxy

The atomic resolution images and x-ray diffraction patterns verified a lattice matched and band-gap engineered device structure of IHET.

Modeling of electrical properties based on its composition and doping

Photoluminescence data indicated the composition and a deep energy level in hot electron filter

Investigation of structural, optical and transport properties by means of transmission electron microscopy, x-ray diffraction, Photoluminescence, Raman spectroscopy, current-voltage measurement

Current-voltage data showed high-pass filter blocks the tunneling dark current, with resulting satisfactory detectivity

Optimization of the composition, thickness, and doping of high-pass filter


Mitra Dutta, ECE and Michael A. Stroscio, ECE and BioE Primary Grant Support: ARO AFOSR

Problem Statement and Motivation •

Semiconductor nanocrystals functionalized with conductive polymers promote efficient charge transfer

Low cost, light weight and tunable conductivities

Explore the application of nanocomposite heterostructures in novel electronic and optoelectronic devices

Key Achievements and Future Goals

Technical Approach •

Fabrication of nanocomposite heterostructures incorporating semiconductor quantum dots and inorganic polymers

Different types of nanocomposite heterostructures have been synthesized

Numerical modeling of the electrical properties

Electrical and optical properties have been studied with modeling and experimental methods

Experimental characterization with optical and electrical measurements

Developing high efficiency photodetectors and solar cells


Investigators: Banani Sen, ECE, Mitra Dutta, ECE, Physics, Michael Stroscio, ECE, BioE, Physics Alex Yarin, MIE, Suman Sinha-Ray, MIE

Problem Statement and Motivation

V

Piezoelectric energy harvesting is necessary to meet today’s energy requirement.

ZnO nanofibers have drawn much attention because of its promising material characteristics.

Bulk production of substrate free nanofibers are needed for various application, viz. power shirts.

L L ± L (a) TEM image of ZnO nanofiber deposited by electrospinning. (b) Schematic representation of energy harvesting measurement setup.

Key Achievements and Future Goals

Technical Approach •

Synthesis of ZnO nanofibers by electrospinning followed by annealing in oxygen ambient.

TEM image shows single crystalline stoichiometric ZnO nanofibers deposited by electrospinning.

Investigation of morphological, optical and material properties by means of Transmission electron microscopy, Photoluminescence and Raman spectroscopy.

Photoluminescence spectrum shows UV peak (near band), Vis peak ( antisite defects and interstitial oxygen).

Synthesis of ZnO nanofiber and PVDF polymer composite by electrospinning for energy harvesting.

Raman scattering- E2 (high), quasi LO and TO modes of mixed A1 and E1 symmetry.

• •

Piezoelectric voltage measurement on application of mechanical strain.

Preliminary electrical measurement results indicate the composite to be promising for energy harvesting. Further systematic study will be continued to evaluate the power density from this piezoelectric composite.


Investigators: Mohsen Purahmed, Mitra Dutta, ECE Department of Electrical Engineering, University of Illinois at Chicago

Problem Statement and Motivation •

ZnO NWs are one of the promising candidates for future nanostructure devices such as short-wavelength semiconductor lasers, light-emitting diodes and energy harvesting devices.

ZnO NWs have a weak near-band-emission (NBE), numerous studies have been done to enhance the NBE and photoluminescence efficiency of ZnO Nanowires (NWs).

ZnO nanowires (NWs) grown by PVD method

Key Achievements and Future Goals

Technical Approach •

Growth of ZnO NWs by PVD method

Optical characterization of ZnO NWs

Enhancement of near-band-emission (NBE )of ZnO

Photoluminescence (PL) of ZnO nanowires coated with the metallic nano particles deposited by rf-magnetron sputtering .

Very strong enhancement of ultraviolet emission is observed after coating with metallic nanoparticles and Ar plasma treatment.

Future goals include studying the waveguiding and lasing effects in these ZnO NWs and making a nano laser with a low threshold lasing power.


Hyeson Jung and Mitra Dutta Department of Electrical and Computer Engineering

Current Density (mA/cm2)

0

Problem Statement and Motivation

68SE1-68AE10

-5 -10 -15

Voc : 0.79V Jsc : 22.96 mA Vmp : 0.62 V Jmp : 19.62 mA FF : 67.06% eff :12.16 %

Current commercial solar cells - single/poly crystalline silicon

Recent crystalline silicon wafer prices increases make second generation cells more attractive

The Second-generation cells – thin film of amorphous Si, CdTe, and CIGS can be competitive

Energy band gap of CdTe is 1.5 eV, considered optimal band gap for solar cells

CdTe solar cell higher efficiency than a-Si

-20 -25 -30 0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Voltage (V)

Key Achievements and Future Goals

Technical Approach •

Fabrication of CdTe thin film solar cell: CdTe, CdS thin film deposition by means of e-beam followed by cell fabrication

Development of alternative post-treatment, and optimization of the treatment condition

Investigation of structural, optical and transport properties by means of Photoluminescence, X-ray spectroscopy, absorption measurement, Scanning Electron Microscopy, Atomic Force Microscope, and current-voltage measurement

CdTe solar cells were fabricated and tested; the CdTe was grown by e-beam evaporation or magnetron sputtering, followed by post treatment.

Alternative post treatment system was developed.

12 % efficiency achieved with first efforts.

Incorporating nanostructures we hope to achieve higher efficiency


Hyeson Jung, Michael Stroscio, Mitra Dutta Department of Electrical and Computer Engineering

(111) 110

En1 ,h1 

 2 212  2 212   Eg * * 2me a 2 2mh a 2

Problem Statement and Motivation •

To explore materials for tandem solar cells, PbSe nanowires were investigated. By adjusting diameter of the wires, bandgap can be engineered. This is one of advantages of nanotechnology.

Nanowires of PbSe are of enhanced interest due to their special properties where the relatively large Bohr excitonic radius and small effective masses lead to strong electron and hole confinement in PbSe nanowires.

PbSe

EC En1 EF EV Eh1

Depletion region, W

Oxidized PbSe surface

Key Achievements and Future Goals

Technical Approach •

Growth of quality PbSe nanowires which are contamination free, compatible with device processing, less expensive and simple by using RF sputter deposition. The optical properties of the wires were characterized by absorption and photoluminescence.

Investigate possibility of achieving nanowire behavior in PbSe larger wires that are grown by sputter deposition due to the effect of surface field and a strong depletion layer.

PbSe nanowires grown by magnetron sputtering

Though of large size wires showed a large blue shift demonstrating quantum confining

Attributed to Fermi level and strong band pinning, large band bending and a wide depletion layer

We have demonstrated that effective diameter of the nanowires are adjustable for different band gap materials.

Development of solar cells using these PbSe nanowires in the near future


Ayan Kar and Mitra Dutta, ECE Primary Grant Support: DoE

Problem Statement and Motivation •

Long term need for an inexpensive sensor for the detection of special nuclear materials.

Ideally sensors which are small, with minimal circuit complexity, and non-cryogenic cooling and requiring small manufacturing costs would provide ideal solutions to this problem.

Tin oxide (SnO2) nanowires have demonstrated to have excellent sensing performance which is comparable to or even surpasses the best thin film counterparts.

Key Achievements and Future Goals

Technical Approach •

Nanowire surface modification using annealing.

Fabrication of SnO2 nanowire Schottky diode sensors.

Expose the nanowire sensors to ionizing 20 Curies of Cesium-137 (137Cs) γ –radiation having an energy of 667 KeV.

Investigation of change in diode electrical properties on being exposed to radiation using current-voltage measurements. Change in nanowire structural properties using photoluminescence.

Large changes (~14.8 MΩ) in resistance in the forward bias region were observed after exposure to the 137Cs) γ –radiation.

A maximum sensitivity of 254% was obtained at a radiation dosage of 42,371 mR/hr.

A short sensor response time of 8 seconds with the permanent change in the nanowire resistance after the radiation is turned off.

Future possibility of stand-off remote detection of radioactive sources using a mm-wave (MMW) technique.


Investigators: ; M. Dutta, ECE and M. Stroscio, ECE and BioE

Problem Statement and Motivation Quantum Dots in MEH-PPV Polymer

Gold contacts

ITO

Glass

• Design, fabrication, characterization of QD-based photonabsorbing media embedded in conductive polymers for optoelectronic devices • For underlying concepts see group’s paper on “Applications of Colloidal Quantum Dots,” Microelectronics Journal, 40, 644-649 (2009).

Top view

MEH-PPV Polymer / CdSe Quantum Dot Composite

Technical Approach

Key Achievements and Future Goals

• Design of quantum-dot (QD) ensembles in conductive polymers

• Numerous simulations of electrical and optical properties including robustness and sensitivity to QD-QD separation

• Fabricating quantum-dot (QD) ensembles in conductive polymers

• Numerous simulations for a variety of QD—conductivepolymer systems

• Modeling electrical and optical properties including robustness and sensitivity to QD-QD separation

• Current sensing AFM measurements of I-V curves for a variety of QDs embedded in conducting polymers

• Experimental characterization of integrated structures

• Ultimate goal is realization of multi-wavelength photodetectors

• Multi-wavelength optoelectronics


Vitali Metlushko, Department of Electrical & Computer Engineering and Nanotechnology Core Facility (NCF) Primary Grant Support: NSF ECS grant # ECS-0202780, Antidot and Ring Arrays for Magnetic Storage Applications and NSF NIRT grant # DMR-0210519 : Formation and Properties of Spin-Polarized Quantum Dots in Magnetic Semiconductors by Controlled Variation of Magnetic Fields on the Nanoscale, B. Janko (P.I.), J. K. Furdyna (co-P.I.), M. Dobrowolska (co-P.I.), University of Notre Dame is leading organization, A. M. Chang (Purdue) and V. Metlushko, (UIC)

Problem Statement and Motivation Lorentz image of magnetic nanostructure.

The field of nanoelectronics is overwhelmingly dedicated to the exploitation of the behavior of electrons in electric fields. Materials employed are nearly always semiconductor-based, such as Si or GaAs, and other related dielectric and conducting materials. An emerging basis for nanoelectronic systems is that of magnetic materials. In the form of magnetic random access memories (MRAM), nanoscale magnetic structures offer fascinating opportunities for the development of low-power and nonvolatile memory elements.

SEM image of 700nm MRAM cells. UIC’s Nanoscale Core Facility

Key Achievements and Future Goals

Technical Approach In past few years, the interest in nano-magnetism has encreased rapidly because they offer potential application in MRAM. Modern fabrication techniques allow us to place the magnetic elements so close together that element-element interactions compete with singleelement energies and can lead to totally different switching dynamics. To visualize the magnetization reversal process in individual nanomagnets as well as in high-density arrays, Metlushko and his coauthors employed several different imaging techniques- magnetic force microscopy (MFM), scanning Hall microscopy, magneto-optical (MO) microscopy, SEMPA and Lorentz microscopy (LM).

This project has led to collaboration with MSD, CNM and APS ANL, Katholieke Univesiteit Leuven, Belgium, University of Notre Dame, NIST, Universita` di Ferrara, Italy, Inter-University Micro-Electronics Center (IMEC), Belgium, Cornell University, McGill University and University of Alberta, Canada

During the past 3 years this NSFsupported work resulted in 21 articles in refereed journals already published and 10 invited talks in the US, Europe and Japan.


Investigators: M. Stroscio, ECE and BioE; and M. Dutta, ECE 0 1

Evac

Al0.25Ga0.75N

CdSe Quantum Dot PDCTh Polymer

2 3 4 5 6 7 8 Al0.125Ga0.875N

PDCTh Polymer

Technical Approach • Design of single-photon detectors • Fabricating quantum-dot (QD) ensembles in conductive polymers • Modeling electrical and optical properties including robustness and sensitivity to QD-QD separation

Problem Statement and Motivation • Design, fabrication, characterization of QD-based optoelectronic devices as components of single-photon detectors • For underlying concepts see Mitra Dutta, et al., Colloidal Quantum Dots (QDs) in Optoelectronic Devices --- Solar Cells, Photodetectors, Light-emitting Diodes, in Handbook for SelfAssembled Semiconductor Nanostructures for Novel Devices in Photonics and Electronics, edited by M. Henini, Elsever Publ. (2008) and Ke Sun, Milana Vasudev, Hye-Son Jung, Jianyong Yang, Ayan Kar, Yang Li, Kitt Reinhardt, Preston Snee, Michael A. Stroscio, and Mitra Dutta, Applications of Colloidal Quantum Dots, Microelectronics Journal, 40, 644-649 (2009).

Key Achievements and Future Goals • Numerous simulations of electrical and optical properties including robustness and sensitivity to QD-QD separation • Numerous simulations for a variety of QD—conductivepolymer systems

• Current sensing AFM measurements of I-V curves for a variety of QDs embedded in conducting polymers

• Experimental characterization of integrated structures • Ultimate goal is realization of photodetectors capable of single-photon detection


Zheng Yang, Department of Electrical and Computer Engineering

Problem Statement and Motivation Diluted magnetic semiconductor is a kind of electronic materials with properties of both a semiconductor and a ferromagnetic material. In modern technology, semiconductor materials are used for logic devices such as the CPU in the computers due to its tunable electric conductivity under external electric field (arisen from the bandgap); while the ferromagnetic materials are used for memory devices such as the hard drive in the computers, in which the information storage is carried by the orientation of the majority spin polarization. Diluted magnetic semiconductor material is a combination of both. In a layman language, if a diluted magnetic semiconductor is successfully demonstrated, we may have the CPU and hard drive integrated in one device chip in our computers in the future. The major two obstacles hindering the practical application of diluted magnetic semiconductor are the Curie temperature and whether the ferromagnetism therein is intrinsic. Curie temperature is a critical temperature above which the material loses ferromagnetism.

Technical Approach Whether the ferromagnetism in the diluted magnetic semiconductor is intrinsic or not is determined by whether the spin polarization is carried by the free carriers or localized ions. If it is localized, sometime we call â&#x20AC;&#x153;extrinsicâ&#x20AC;?, it is not applicable for device applications generally. Several diluted magnetic semiconductors have been confirmed as intrinsic ferromagnetism such as Mn-doped GaAs, however, all of them show Curie temperature below room temperature. On the other hand, it has been observed above-room-temperature Curie temperatures in ZnO diluted magnetic semiconductor materials, but whether the ferromagnetism therein is intrinsic is still controversial and needs further clarification from experiments. The most straightforward experiment to investigate whether the ferromagnetism in diluted magnetic semiconductor is intrinsic or not is to study whether the ferromagnetism shows free carrier concentration dependent property.

Key Achievements and Future Goals It has been originally demonstrated that the free carrier concentration dependent ferromagnetism in ZnO diluted magnetic semiconductors. First, It has been experimentally achieved precise control of free carrier concentration in ZnO thin films with Ga doping. Then these ZnO thin films with different free carrier concentration were doped with magnetic dopants. It has been first time observed that the larger free carrier concentration leads to larger magnetization. Comprehensive electron microscopy and x-ray diffraction studies have been performed to exclude the possibility of the existence of localized magnetic clusters inside the ZnO diluted magnetic semiconductors. In the next steps, two major research projects will be carried out. The first is to study electrostatic doping (via a gate voltage instead of chemical doping) effect on the magnetic properties of ZnO diluted magnetic semiconductors. The second is to investigate the magnetic properties of ZnO diluted magnetic semiconductor in lowdimensional systems, such as nanowries.


Kenneth Brezinsky Kenbrez@uic.edu

Problem Statement and Motivation In order to improve internal combustion engine fuel efficiency and mitigate the emission of harmful pollutants, there is a need for predictive chemical and physical models that can predict the behavior of real fuels from the fuel tank to the exhaust. Chemical details of how fuels burn determine their • Burning efficiency: i.e. energy saving, • Cleanness : i.e. soot, NOx, particulates, priority pollutants • Applications: i.e. aviation, spark ignited, or diesel engines; stationary power plants

Single Pulse High Pressure Shock tube Lower Pressure Single Pulse Shock Tube

Future, alternative, fuels will have different chemical burning characteristics; • Combustion chemistry information is necessary of future application

Funding sources: NSF, AFOSR, DOE, NASA, DOD

Technical Approach Develop a chemical experimental and kinetic modeling validation database at real combustor conditions. • • • •

Experiments conducted in two different shock tubes 1) Very high pressure tube: 15-1000 bar 2) Lower pressure tube: 1 -10 bar Chemical species obtained as a function of temperature (6002500K) for a given pressure and time (1- 3 msec) • Species concentrations simulated with detailed chemical models developed in our laboratory

Key Achievements and Future Goals Representative Publications: • “Experimental and modeling study on the pyrolysis and oxidation of n-decane and n-dodecane”, Proc. Combust. Inst., 34, 361-368, 2013. (T. Malewicki, K. Brezinsky) • “Experimental and modeling study on the oxidation of Jet A and the n-dodecane/iso-octane/n-propylbenzene/1,3,5trimethylbenzene surrogate fuel “, Comb. Flame, 160(1), 1730, 2013 (T. Malewicki, S. Gudiyella and K. Brezinsky). • “Pyrolysis of n-Heptane and Oxidation in Mixtures of Ethylene/Methane and iso-Octane” , J. Prop. Power 29, 732743, 2013 (A. Fridlyand, A. Mandelbaum and K. Brezinsky).


Carmen M. Lilley, Mechanical Engineering Primary Grant Support: NSF

Problem Statement and Motivation

FIG. 1: (a) Micrograph of a Ag nanowire under 4-probe I-V measurement, (b) STM scan of the cross-section from left-to-right, (c) line scan profile of cross-section from left-to-right (solid curve) and right-to-left (dashed curve).

Successful integration of nanosystems into microelectronics depends on stable material properties that are reliable for at least a 10 year lifecycle with over a trillion cycles of operation.

Fundamental understanding of the physics of deformation and failure in nanometer scale capped or layered structures, where surfaces play a dominant role, does not exist. Prior work has mostly focused on monolithic nanometer scale materials.

FIG. 2: Electromigration of a Cu nanowire with the current stress of 4.2 mA (length = 2.04 µm, width = 90 nm, and thickness = 50nm): (a) 0 min, (b) 40 min, (c) 80 min, (d) 120 min, and (e) 137.5 min.

Key Achievements and Future Goals

Technical Approach •

Identify surface contaminants present in as-synthesized nanowires according to metallic, organic, and mixed-materials classifications.

Measure the electrical properties of as-synthesized nanowires and identify contamination effects on electrical properties with an accuracy of 5%.

Measure the stability of electrical properties of nanowires under accelerated electrical testing and classified according to structure.

[1] [2] [3] [4]

Preliminary results on measuring the presence of surface contaminants and their influence on electrical properties completed [1].

In depth study on size and surface effects on electromigration for Cu and Au nanowires have been performed [2-4]

Additionally, this work has been extended to studying electron surface scattering for single crystalline Ag nanowires.

C. M. Lilley, Q. J. Huang, Applied Physics Letters 2006, 89, 203114. Q. J. Huang, C. M. Lilley, M. Bode, R. Divan, Journal of Applied Physics 2008, 104, 23709. Q. Huang, C. M. Lilley, R. Divan, Nanotechnology 2009, 20, 075706. Q. Huang, C. M. Lilley, R. S. Divan, M. Bode, IEEE Transactions in Nanotechnology 2008, 7, 688.]


A. Salehi-Khojin, Mechanical and Industrial Engineering

Problem Statement and Motivation • To perform a fundamental understanding of chemical sensing in graphene-based chemical field effect transistors for the development of next generation chemical sensors. • To examine the sensing performance of external defects on insulating substrate and internal defects on graphene surface. • To study the effect of humidity and different dopant on the sensitivity of graphene sensors.

Technical Approach • Device fabrication, characterizations and sensing experiments under different conditions • Density Functional Theory calculations to explore the sensing mechanism in graphene

• Suspended graphene fabrication to deconvolute the role of external defects on substrate B. Kumar, K. Min, M. Bashirzadeh, A. Barati-Farimani, M.-H. Bae, D. Estrada, , Y. D. Kim, P. Yasaei, Y. D. Park, E. Pop, N. R. Aluru, A. Salehi-Khojin, The Role of External Defects in Chemical Sensing of Graphene Field-Effect Transistors, NanoLetters, 3 (5), 1962–1968, 2013.

Key Achievements and Future Goals


Suresh K. Aggarwal, Mechanical and Industrial Engineering

Problem Statement and Motivation •

Use of Monte Carlo and Molecular Dynamics methods to investigate thermodynamics and flow processes at nanoscales

Dynamics of droplet collision and interfacial processes

Interaction of a nanodroplet with carbon nanotube

Solid-liquid Interactions and Nanolubrication

Vaporization of a non-spherical nano-droplet

Key Achievements and Future Goals

Technical Approach Z

1000 Steps

X

30

z

20 0 10 20 30

0 0

40 50

10

y

60

20

x

70

30 40

Molecular Dynamics Simulation of Droplet Evaporation, Int. J. of Heat & Mass Transfer, 46, pp. 3179-3188, 2003.

Molecular Dynamics Simulations of Droplet Collision. M.S. Thesis, K. Shukla, 2003.

Y

40

10

80

MD simulation of the collision between two nano-droplets


Carmen M. Lilley, Mechanical Engineering (a)

x

Problem Statement and Motivation

Undeformed NW centerline

v

Deformed NW centerline

Surface effects, such as a surface elastic modulus and surface stress have been predicted for FCC NWs from atomistic simulations.

(c)

Experimentally, elastic modulus measurements of FCC metal NWs have been found to vary widely. Some results indicate apparent size effects, other studies indicate no size effects.

For Nanoelectromechanical Systems (NEMS), accurate elastic properties are necessary to design devices.

p(x)=Hv'' (b)

Left

Top w

t1 Right t z

O y Bottom

t1

D

O θ y Surface

z

Note: Drawings are not to scale.

Modeling Surface Stress Effects on the Static Bending Behavior of Nanowires (NW). (a) Schematic of the undeformed and deformed NW centerline. (b) Crosssectional view of a rectangular NW with the surface highlighted. (c) Crosssectional view of circular NW with the surface highlighted..

Key Achievements and Future Goals

Technical Approach •

Model the elastic bending behavior of face centered cubic (FCC) metals with continuum mechanics.

Derived analytical solutions for NWs under static and dynamic bending. [1,2]

Apply Young-Laplace Theory to study transverse load effects as a result of surface stress of nanowires (NWs) due to undercoordinated atoms at the surface.

Validated theory that surface stress and boundary conditions affect the apparent elastic modulus measured experimentally. [1,2]

Study the influence of boundary conditions on the resultant bending mechanical behavior of nanowires.

Proposed a surface effect factor as a qualitative parameter predict the influence of surface stress and geometry on the elastic behavior of static bending nanowires. [1,2]

Test hypothesis that surface stress and boundary conditions affect the apparent elastic modulus of NWs.

Extending the method to large deformation of nanowires for application to NEMS resonators. [3]

[1] J. He, C. M. Lilley, Nano Letters 2008, 8, 1798. [2] J. He, C. M. Lilley, Applied Physics Letters 2008, 93, 263108. [3] J. He, C. M. Lilley, Computational Mechanics In Press.


Farzad Mashayek, MIE/UIC; Themis Matsoukas, ChE/Penn State Primary Grant Support: NSF

Problem Statement and Motivation

Simulated flow of ions over a nanoparticle

Nanoparticles of various materials are building blocks and important constituents of ceramics and metal composites, pharmaceutical and food products, energy related products such as solid fuels and batteries, and electronics related products. The ability to manipulate the surface properties of nanoparticles through deposition of one or more materials can greatly enhance their applicability.

Nanolayer coating on a silica particle

Key Achievements and Future Goals

Technical Approach A low-pressure, non-equilibrium plasma process is developed using experimental and computational approaches. Two types of reactors are being considered. The first reactor operates in “batch” mode by trapping the nanoparticles in the plasma sheath. Agglomeration of the particles is prevented due to the negative charges on the particles. The second reactor is being designed to operate in a “continuous” mode where the rate of production may be significantly increased. This reactor will also provide a more uniform coating by keeping the nanoparticles outside the plasma sheath.

The batch reactor is already operational and has been used to demonstrate the possibility of coating nanoparticles.

A reaction model has been developed to predict the deposition rate on the nanoparticle surface.

The possibility of using an external magnetic field to control the trapping of the particles has been investigated computationally.

The experimental effort is now focused on the design of the “continuous” mode reactor.

The computational effort is focused on development of a comprehensive code for simulation of the plasma reactor, nanoparticle dynamics, and surface deposition.


C. M. Megaridis, A. Yarin, Mechanical and Industrial Eng., UIC; Y. Gogotsi, J.C. Bradley, Drexel Univ.; H. Bau, Univ. Pennsylvania Primary Grant Support: National Science Foundation

Problem Statement and Motivation •

Investigate the physical and chemical properties of aqueous fluids contained in multiwall carbon nanotubes

Determine the continuum limit for fluid behavior under extreme confinement

Provide experimental data for parallel modeling efforts

Evaluate the feasibility of fabricating devices using carbon nanotubes as building blocks

Key Achievements and Future Goals

Technical Approach •

Multiwall carbon nanotubes filled by high-pressure high-temperature processing in autoclaves

Gas/Liquid interfaces in carbon nanotubes with diameter above 10nm resemble interfaces in macroscopic capillaries

Nanotube diameter in the range 5nm-200nm, and lengths 500nm10μm

Non-continuum behavior observed in nanotubes with diameter below 10nm

Gas/liquid interfaces used as markers of fluid transport

Wettability of carbon walls by water observed; important property for adsorption applications

High-resolution electron microscopy and chemical analysis techniques used to resolve behavior of fluids stimulated thermally in the electron microscope

Future applications include drug delivery systems, lab-on-a-chip manufacturing, electrochemical cells, etc.

Model simulations used to interpret experimental observations


C. M. Megaridis, Mechanical and Industrial Engineering; C. Takoudis, Bioengineering; J. Belot, Univ. Nebraska-Lincoln; J. McAndrew, Air Liquide, Inc. Primary Grant Support: Air Liquide

Problem Statement and Motivation •

Patterned metal films are essential to a wide range of applications ranging from printed circuits, to thin-film displays and electrodes in biomedical implants

Inkjet printing has environmental benefits while offering flexibility, cost savings, and scalability to large area substrates

Initial focus on Copper due to its very low resistivity. Future extension to bio-compatible metals

Homogeneous metal inks eliminate obstacles encountered while using nanoparticle ink suspensions

Key Achievements and Future Goals

Technical Approach •

Synthesis of metal compounds as primary ingredients of homogeneous inks

Ink physical and rheological properties (viscosity, surface tension) optimized for printability

Printing tests for optimal line formation; thermal treatment to reduce the deposit to pure metal; final product testing/evaluation

X-ray photoelectron spectroscopy and electron microscopy used to characterize deposit chemical composition and surface quality

Candidate organocopper compounds and solvents have been identified, providing facile decomposition to metallic copper (removal of ligands + reduction of Cu2+ to Cu0), and copper content > 10% wt.

Copper lines printed in the laboratory indicate that homogeneous solutions of organocopper compounds can be developed with suitable properties for ink-jet printing

Research has the potential to catapult progress in metal ink fabrication and in-situ formation of metallic lines with feature size in the 10-100 mm range


Laxman Saggere, Mechanical and Industrial Engineering Primary Grant Support: NSF

Problem Statement and Motivation A 20-mm sphere gripped & moved by two fingers SEM of the micromanipulator chip Integrated micromanipulator system

A 20-mm sphere rotated between two fingers

A micro-object gripped & moved by the fingers

Motivation: Nanomanufacturing is critical for building new functional and useful products. Nanomanufacturing by an assembly-based approach promises to fill the void between the current “bottom-up” and “top-down” approaches and enable assembly of building blocks in future NEMS. However, despite recent advances, currently available tools and techniques for mechanical manipulation of micro/nano-scale objects lack dexterity to accomplish complex assembly of nano-scale objects. The success of assembly-based nanomanufacturing will depend on a micromanipulator tool with high-degree of dexterity beyond that provided by current simple cantilevers and parallel jaw grippers and tweezers. Objectives: To investigate the principles and fundamental issues in a novel manipulation methodology based on the coordinated action of multiple agile fingers at a chipscale to accomplish controlled contact manipulation tasks such as grasp, rotate, regrasp, move and position micro- and nano-scale objects in a defined 2D workspace.

Experimental setup including user control inputs and visual feedback A micro-object rotated between two fingers

Technical Approach The approach involves a novel chipscale micromanipulator comprised of four (or more) tiny compliant fingers, each of which can be independently actuated by integrated piezo actuators. By providing controlled actuation, the fingers can be guided to move in-plane and coordinate with each other to carry out controlled manipulation tasks such as grasp, rotate, move point-to-point and position micro- and nano-scale objects and perform assembly operations in a defined 2D workspace in the plane of the chip. The actuation, and thus, the motion of the micromanipulator fingers can be controlled by means of external user inputs via a gaming controller or a programmed software and visual feedback of locations and motions of the fingers/objects on a video monitor.

Key Achievements and Future Goals Key Achievements: A novel micromanipulation system comprised of a multifingered micromanipulator chip integrated with piezo actuators and enclosed in a precision-machined custom housing has been developed. This micromanipulator system enables highly dexterous manipulations of micro-scale objects on the chip by coordinated action of the fingers when controlled in a close-loop by external user inputs supplied via a wireless gamming controller.

Future Goals: To achieve high precision coordinated manipulation of micro/nano-scale objects incorporating a more sophisticated position/force feedback and a fully programmed motion planning for assembly of the objects in the manipulator workspace.


S. Sinha-Ray, Y. Zhang, Prof. A.L. Yarin (MIE, UIC)

Problem Statement and Motivation •

Development of a novel method of solution blowing of monolithic and core-shell nanofibers.

Incorporation of such by-products of BioDiesel production as soy protein into solution blown nanofibers.

Demonstration of robust nanofiber nonwovens containing soy protein.

Carbonization of core-shell polymer nanofibers and transforming them into amorphous carbon nanotubes.

Key Achievements and Future Goals

Technical Approach •

Solution blowing with gas speeds of about 230-270 m/s.

Solutions of soy protein and Nylon-6 in formic acid.

Collection of nanofibers on rotating drums.

Carbonization to make carbon nanotubes.

SEM, staining and fluorescence imaging.

To appear in Biomacromolecules (in press, 2011)

Demonstration that solution blowing can produce nanofibers at a high rate.

Formation of carbon nanotubes from core-shell nanofibers.

Formation of robust nanofiber nonwovens containing about 40% of soy protein.

Future work will explore strength of soy protein nonwovens; nanofibers will be decorated with silver nanoparticles for applications in catalysis.


S. Sinha-Ray, Y. Zhang, Prof. A.L. Yarin (MIE, UIC)

Problem Statement and Motivation •

Nano-textured surfaces for the enhanced spray cooling, especially for microelectronics, avionics and space applications.

Drop cooling with local heat removal rates of about 1 kW/sq.cm.

Electrokinetic delivery of coolant to nano-textured surfaces (joint with IIT).

Suppression of drop receding and bouncing.

Significant surface area enhancement.

Key Achievements and Future Goals

Technical Approach •

Electrospinning of polymer (PAN) nanofiber mats onto a wafer.

Sputter coating with Pt-Pd to a thickness of 15 nm.

Metal-plating onto nanofibers with control of grain sizes.

Drop impact: water and Fluorinerts.

SEM and CCD Camera imaging.

Published in Langmuir 27, 215-226 (2011) and Physical Review E v. 83, 036305 (2011)

Contact line of a fully spread-out drop is pinned, practically no splashing, receding and bouncing.

The physical mechanism of pinning and millipede-like drop structure is kindred to the shaped-charge (Munroe) jets.

Local heat removal rates of the of about 0.7 kW/sq.cm have been demonstrated with water.

Future work will explore pinning of drops at substrates at temperatures of 200-300 C, detail impacts of Fluorinerts and measure heat removal rates for them.

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