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Mechanical Engineering Publications

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Articles 1 - 26 of 26

Full-Text Articles in Applied Mechanics

Synthesis Of Graphene Nanosheets Through Spontaneous Sodiation Process, Deepak-George Thomas, Emrah Kavak, Niloofar Hashemi, Reza Montazami, Nicole N. Hashemi Jul 2018

Synthesis Of Graphene Nanosheets Through Spontaneous Sodiation Process, Deepak-George Thomas, Emrah Kavak, Niloofar Hashemi, Reza Montazami, Nicole N. Hashemi

Mechanical Engineering Publications

Graphene is one of the emerging materials in the nanotechnology industry due to its potential applications in diverse areas. We report the fabrication of graphene nanosheets by spontaneous electrochemical reaction using solvated ion intercalation into graphite. The current literature focuses on the fabrication of graphene using lithium metal. Our procedure uses sodium metal, which results in a reduction of costs. Using various characterization techniques, we confirmed the fabrication of graphene nanosheets. We obtained an intensity ratio (ID/IG) of 0.32 using Raman spectroscopy, interlayer spacing of 0.39 nm and our XPS results indicate that our fabricated compound is ...


Theoretical And Experimental Investigation Of Forward Spatter Of Blood From A Gunshot, P. M. Comiskey, A. L. Yarin, Daniel Attinger Jun 2018

Theoretical And Experimental Investigation Of Forward Spatter Of Blood From A Gunshot, P. M. Comiskey, A. L. Yarin, Daniel Attinger

Mechanical Engineering Publications

A theoretical model predicting forward blood spatter patterns resulting from a round nose bullet gunshot wound is proposed. The chaotic disintegration of a blood layer located ahead and aside of the bullet is considered in the framework of percolation theory. The size distribution of blood drops is determined, which allows for the prediction of a blood spatter cloud being ejected from the rear side of the target where the bullet exits. Then, droplet trajectories are numerically predicted accounting for gravity and air drag, which is affected by the collective aerodynamic interaction of drops through air. The model predicts the number ...


Hydrodynamics Of Back Spatter By Blunt Bullet Gunshot With A Link To Bloodstain Pattern Analysis, P. M. Comiskey, A. L. Yarin, Daniel Attinger Jul 2017

Hydrodynamics Of Back Spatter By Blunt Bullet Gunshot With A Link To Bloodstain Pattern Analysis, P. M. Comiskey, A. L. Yarin, Daniel Attinger

Mechanical Engineering Publications

A theoretical model describing the blood spatter pattern resulting from a blunt bullet gunshot is proposed. The predictions are compared to experimental data acquired in the present work. This hydrodynamic problem belongs to the class of the impact hydrodynamics with the pressure impulse generating the blood flow. At the free surface, the latter is directed outwards and accelerated toward the surrounding air. As a result, the Rayleigh-Taylor instability of the flow of blood occurs, which is responsible for the formation of blood drops of different sizes and initial velocities. Thus, the initial diameter, velocity, and acceleration of the atomized blood ...


A Farm-Level Precision Land Management Framework Based On Integer Programming, Qi Li, Guiping Hu, Talukder Jubery, Baskar Ganapathysubramanian Mar 2017

A Farm-Level Precision Land Management Framework Based On Integer Programming, Qi Li, Guiping Hu, Talukder Jubery, Baskar Ganapathysubramanian

Mechanical Engineering Publications

Farmland management involves several planning and decision making tasks including seed selection and irrigation management. A farm-level precision farmland management model based on mixed integer linear programming is proposed in this study. Optimal decisions are designed for pre-season planning of crops and irrigation water allocation. The model captures the effect of size and shape of decision scale as well as special irrigation patterns. The authors illustrate the model with a case study on a farm in the state of California in the U.S. and show the model can capture the impact of precision farm management on profitability. The results ...


A Finite Element Approach To Self-Consistent Field Theory Calculations Of Multiblock Polymers, David M. Ackerman, Kris Delaney, Glenn H. Fredrickson, Baskar Ganapathysubramanian Feb 2017

A Finite Element Approach To Self-Consistent Field Theory Calculations Of Multiblock Polymers, David M. Ackerman, Kris Delaney, Glenn H. Fredrickson, Baskar Ganapathysubramanian

Mechanical Engineering Publications

Self-consistent field theory (SCFT) has proven to be a powerful tool for modeling equilibrium microstructures of soft materials, particularly for multiblock polymers. A very successful approach to numerically solving the SCFT set of equations is based on using a spectral approach. While widely successful, this approach has limitations especially in the context of current technologically relevant applications. These limitations include non-trivial approaches for modeling complex geometries, difficulties in extending to non-periodic domains, as well as non-trivial extensions for spatial adaptivity. As a viable alternative to spectral schemes, we develop a finite element formulation of the SCFT paradigm for calculating equilibrium ...


Contaminant Transport At Large Courant Numbers Using Markov Matrices, Anthony D. Fontanini, Umesh Vaidya, Alberto Passalacqua, Baskar Ganapathysubramanian Feb 2017

Contaminant Transport At Large Courant Numbers Using Markov Matrices, Anthony D. Fontanini, Umesh Vaidya, Alberto Passalacqua, Baskar Ganapathysubramanian

Mechanical Engineering Publications

Volatile organic compounds, particulate matter, airborne infectious disease, and harmful chemical or biological agents are examples of gaseous and particulate contaminants affecting human health in indoor environments. Fast and accurate methods are needed for detection, predictive transport, and contaminant source identification. Markov matrices have shown promise for these applications. However, current (Lagrangian and flux based) Markov methods are limited to small time steps and steady-flow fields. We extend the application of Markov matrices by developing a methodology based on Eulerian approaches. This allows construction of Markov matrices with time steps corresponding to very large Courant numbers. We generalize this framework ...


Comparison Of A Virtual Game-Day Experience On Varying Devices, Jack Miller, Holly Baiotto, Anastacia Macallister, Melynda Hoover, Gabriel Evans, Jonathan Schlueter, Vijay Kalivarapu, Eliot H. Winer Jan 2017

Comparison Of A Virtual Game-Day Experience On Varying Devices, Jack Miller, Holly Baiotto, Anastacia Macallister, Melynda Hoover, Gabriel Evans, Jonathan Schlueter, Vijay Kalivarapu, Eliot H. Winer

Mechanical Engineering Publications

Collegiate athletics, particularly football, provide tremendous value to schools through branding, revenue, and publicity. As a result, extensive effort is put into recruiting talented students. When recruiting, home games are exceptional tools used to show a school's unique game-day atmosphere. However, this is not a viable option during the offseason or for off-site visits. This paper explores a solution to these challenges by using virtual reality (VR) to recreate the game-day experience. The Virtual Reality Application Center in conjunction with Iowa State University (ISU) athletics, created a VR application mimicking the game-day experience at ISU. This application was displayed ...


Computer Vision And Machine Learning For Robust Phenotyping In Genome-Wide Studies, Jiaoping Zhang, Hsiang Sing Naik, Teshale Assefa, Soumik Sarkar, R. V. Chowda Reddy, Arti Singh, Baskar Ganapathysubramanian, Asheesh K. Singh Jan 2017

Computer Vision And Machine Learning For Robust Phenotyping In Genome-Wide Studies, Jiaoping Zhang, Hsiang Sing Naik, Teshale Assefa, Soumik Sarkar, R. V. Chowda Reddy, Arti Singh, Baskar Ganapathysubramanian, Asheesh K. Singh

Mechanical Engineering Publications

Traditional evaluation of crop biotic and abiotic stresses are time-consuming and labor-intensive limiting the ability to dissect the genetic basis of quantitative traits. A machine learning (ML)-enabled image-phenotyping pipeline for the genetic studies of abiotic stress iron deficiency chlorosis (IDC) of soybean is reported. IDC classification and severity for an association panel of 461 diverse plant-introduction accessions was evaluated using an end-to-end phenotyping workflow. The workflow consisted of a multi-stage procedure including: (1) optimized protocols for consistent image capture across plant canopies, (2) canopy identification and registration from cluttered backgrounds, (3) extraction of domain expert informed features from the ...


Enhanced Enzymatic Activity From Phosphotriesterase Trimer Gold Nanoparticle Bioconjugates For Pesticide Detection, John A. Hondred, Joyce C. Breger, Nate T. Garland, Eunkeu Oh, Kimihiro Susumu, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen Jan 2017

Enhanced Enzymatic Activity From Phosphotriesterase Trimer Gold Nanoparticle Bioconjugates For Pesticide Detection, John A. Hondred, Joyce C. Breger, Nate T. Garland, Eunkeu Oh, Kimihiro Susumu, Scott A. Walper, Igor L. Medintz, Jonathan C. Claussen

Mechanical Engineering Publications

The rapid detection of organophosphates (OPs), a class of strong neurotoxins, is critically important for monitoring acute insecticide exposure and potential chemical warfare agent use. Herein, we improve the enzymatic activity of a phosphotriesterase trimer (PTE3), an enzyme that selectively recognizes OPs directly, by conjugation with distinctly sized (i.e., 5, 10, and 20 nm diameter) gold nanoparticles (AuNPs). The number of enzymes immobilized on the AuNP was controlled by conjugating increasing molar ratios of PTE3 onto the AuNP surface via metal affinity coordination. This occurs between the PTE3-His6 termini and the AuNP-displayed Ni2+-nitrilotriacetic acid end groups and was ...


A Real-Time Phenotyping Framework Using Machine Learning For Plant Stress Severity Rating In Soybean, Hsiang Sing Naik, Jiaoping Zhang, Alec Lofquist, Teshale Assefa, Soumik Sarkar, David M. Ackerman, Arti Singh, Asheesh K. Singh, Baskar Ganapathysubramanian Jan 2017

A Real-Time Phenotyping Framework Using Machine Learning For Plant Stress Severity Rating In Soybean, Hsiang Sing Naik, Jiaoping Zhang, Alec Lofquist, Teshale Assefa, Soumik Sarkar, David M. Ackerman, Arti Singh, Asheesh K. Singh, Baskar Ganapathysubramanian

Mechanical Engineering Publications

Background: Phenotyping is a critical component of plant research. Accurate and precise trait collection, when integrated with genetic tools, can greatly accelerate the rate of genetic gain in crop improvement. However, efficient and automatic phenotyping of traits across large populations is a challenge; which is further exacerbated by the necessity of sampling multiple environments and growing replicated trials. A promising approach is to leverage current advances in imaging technology, data analytics and machine learning to enable automated and fast phenotyping and subsequent decision support. In this context, the workflow for phenotyping (image capture → data storage and curation → trait extraction → machine ...


Thermodynamics And Historical Relevance Of A Jetting Thermometer Made Of Chinese Zisha Ceramic, Vincent Lee, Daniel Attinger Jul 2016

Thermodynamics And Historical Relevance Of A Jetting Thermometer Made Of Chinese Zisha Ceramic, Vincent Lee, Daniel Attinger

Mechanical Engineering Publications

Following a recent trend of scientific studies on artwork, we study here the thermodynamics of a thermometer made of zisha ceramic, related to the Chinese tea culture. The thermometer represents a boy who “urinates” shortly after hot water is poured onto his head. Long jetting distance is said to indicate that the water temperature is hot enough to brew tea. Here, a thermodynamic model describes the jetting phenomenon of that pee-pee boy. The study demonstrates how thermal expansion of an interior air pocket causes jetting. A thermodynamic potential is shown to define maximum jetting velocity. Seven optimization criteria to maximize ...


Machine Learning For High-Throughput Stress Phenotyping In Plants, Arti Singh, Baskar Ganapathysubramanian, Asheesh Kumar Singh, Soumik Sarkar Feb 2016

Machine Learning For High-Throughput Stress Phenotyping In Plants, Arti Singh, Baskar Ganapathysubramanian, Asheesh Kumar Singh, Soumik Sarkar

Mechanical Engineering Publications

Advances in automated and high-throughput imaging technologies have resulted in a deluge of high-resolution images and sensor data of plants. However, extracting patterns and features from this large corpus of data requires the use of machine learning (ML) tools to enable data assimilation and feature identification for stress phenotyping. Four stages of the decision cycle in plant stress phenotyping and plant breeding activities where different ML approaches can be deployed are (i) identification, (ii) classification, (iii) quantification, and (iv) prediction (ICQP). We provide here a comprehensive overview and user-friendly taxonomy of ML tools to enable the plant community to correctly ...


Platinum Nanoparticle Decorated Sio2 Microfibers As Catalysts For Micro Unmanned Underwater Vehicle Propulsion, Bolin Chen, Nathaniel T. Garland, Jason Geder, Marius Pruessner, Eric Mootz, Allison Cargill, Anne Leners, Granit Vokshi, Jacob Davis, Wyatt Burns, Michael A. Daniele, Josh Kogot, Igor L. Medintz, Jonathan C. Claussen Jan 2016

Platinum Nanoparticle Decorated Sio2 Microfibers As Catalysts For Micro Unmanned Underwater Vehicle Propulsion, Bolin Chen, Nathaniel T. Garland, Jason Geder, Marius Pruessner, Eric Mootz, Allison Cargill, Anne Leners, Granit Vokshi, Jacob Davis, Wyatt Burns, Michael A. Daniele, Josh Kogot, Igor L. Medintz, Jonathan C. Claussen

Mechanical Engineering Publications

Micro unmanned underwater vehicles (UUVs) need to house propulsion mechanisms that are small in size but sufficiently powerful to deliver on-demand acceleration for tight radius turns, burst-driven docking maneuvers, and low-speed course corrections. Recently, small-scale hydrogen peroxide (H2O2) propulsion mechanisms have shown great promise in delivering pulsatile thrust for such acceleration needs. However, the need for robust, high surface area nanocatalysts that can be manufactured on a large scale for integration into micro UUV reaction chambers is still needed. In this report, a thermal/electrical insulator, silicon oxide (SiO2) microfibers, is used as a support for platinum nanoparticle (PtNP) catalysts ...


A Paper-Based Microbial Fuel Cell Operating Under Continuous Flow Condition, Niloofar Hashemi, Joshua M. Lackore, Farrokh Sharifi, Payton J. Goodrich, Megan L. Winchell, Nicole N. Hashemi Jan 2016

A Paper-Based Microbial Fuel Cell Operating Under Continuous Flow Condition, Niloofar Hashemi, Joshua M. Lackore, Farrokh Sharifi, Payton J. Goodrich, Megan L. Winchell, Nicole N. Hashemi

Mechanical Engineering Publications

Microbial fuel cells have gained popularity as a viable, environmentally friendly alternative for the production of energy. However, the challenges in miniaturizing the system for application in smaller devices as well as the short duration of operation have limited the application of these devices. Here, the capillary motion was employed to design a self-pumped paper-based microbial fuel cell operating under continuous flow condition. A proof-of-concept experiment ran approximately 5 days with no outside power or human interference required for the duration of operation. Shewanella oneidensis MR-1 was used to create a maximum current of 52.25 µA in a 52 ...


Investigation Of Friction Mechanisms In Finger Pad Sliding Against Surfaces Of Varying Roughness, Geetha Chimata, Christian J. Schwartz Sep 2015

Investigation Of Friction Mechanisms In Finger Pad Sliding Against Surfaces Of Varying Roughness, Geetha Chimata, Christian J. Schwartz

Mechanical Engineering Publications

Human finger pad friction and the effects of surface features on the fingerprint ridges, shape of the finger and the material properties of the finger were investigated. The friction coefficients for three fine-grit abrasive papers were measured to assess these effects. Four probing surfaces were used: human index finger pad, silicone replicas of the finger with and without fingerprints, and a smooth silicone sphere. Friction tests were performed at a constant normal load of 0.5 N in two probe orientations: normal and perpendicular to the orientation of the fingerprint ridges. Scanning electron microscopy of the abrasive papers was performed ...


Isogeometric Kirchhoff–Love Shell Formulations For General Hyperelastic Materials, Josef Kiendl, Ming-Chen Hsu, Michael C. H. Wu, Alessandro Reali Jul 2015

Isogeometric Kirchhoff–Love Shell Formulations For General Hyperelastic Materials, Josef Kiendl, Ming-Chen Hsu, Michael C. H. Wu, Alessandro Reali

Mechanical Engineering Publications

We present formulations for compressible and incompressible hyperelastic thin shells which can use general 3D constitutive models. The necessary plane stress condition is enforced analytically for incompressible materials and iteratively for compressible materials. The thickness stretch is statically condensed and the shell kinematics are completely described by the first and second fundamental forms of the midsurface. We use C1-continuous isogeometric discretizations to build the numerical models. Numerical tests, including structural dynamics simulations of a bioprosthetic heart valve, show the good performance and applicability of the presented methods.


An Analysis Of Current And Future Wind Energy Gain Potential For Central Iowa, Farrokh Sharifi, Nicole N. Hashemi Jan 2015

An Analysis Of Current And Future Wind Energy Gain Potential For Central Iowa, Farrokh Sharifi, Nicole N. Hashemi

Mechanical Engineering Publications

Using a significant quantity of fossil fuels has adverse impacts on our lives and will affect future generations. Additionally, there are limited and decreasing numbers of non-renewable resources around the world. In contrast, renewable resources are not depleted and provide energy with negligible pollution. Wind energy is one of the more common renewable energy resources. This project aims to evaluate Iowa's wind energy potential and to provide suggestions to improve the future well‐being of this state. A preliminary analysis shows that Iowa has great potential for wind energy. Based on the preliminary analysis, Ames, Iowa, is selected as ...


Investigation Of The Effect Of The Normal Load On The Incidence Of Friction Blisters In A Skin-Simulant Model, Geetha Chimata, Christian J. Schwartz Jan 2015

Investigation Of The Effect Of The Normal Load On The Incidence Of Friction Blisters In A Skin-Simulant Model, Geetha Chimata, Christian J. Schwartz

Mechanical Engineering Publications

A laminar skin simulant was constructed to study the incidence of friction blisters. The skin simulant consists of a thin polyurethane top layer and textured gum foam rubber bottom layer adhered to an acrylic-backing plate to emulate the layered structure of the human skin. Friction blisters were produced on the skin simulant by using a dual-axis tribometer. The effect of the applied normal load on the number of cycles required to produce a blister was investigated. The skin simulant was also analyzed as an adhesive-bonded laminar composite to determine the relationship between the applied normal load and the number of ...


Immersive Computing Technology To Investigate Tradeoffs Under Uncertainty In Disassembly Sequence Planning, Sara Behdad, Leif P. Berg, Judy M. Vance, Deborah Thurston Apr 2014

Immersive Computing Technology To Investigate Tradeoffs Under Uncertainty In Disassembly Sequence Planning, Sara Behdad, Leif P. Berg, Judy M. Vance, Deborah Thurston

Mechanical Engineering Publications

The scientific and industrial communities have begun investigating the possibility of making product recovery economically viable. Disassembly sequence planning may be used to make end-of-life product take-back processes more cost effective. Much of the research involving disassembly sequence planning relies on mathematical optimization models. These models often require input data that is unavailable or can only be approximated with high uncertainty. In addition, there are few mathematical models that include consideration of the potential of product damage during disassembly operations. The emergence of Immersive Computing Technologies (ICT) enables designers to evaluate products without the need for physical prototypes. Utilizing unique ...


Leveraging Virtual Reality Experiences With Mixed-Integer Nonlinear Programming Visualization Of Disassembly Sequence Planning Under Uncertainty, Sara Behdad, Leif P. Berg, Deborah Thurston, Judy M. Vance Feb 2014

Leveraging Virtual Reality Experiences With Mixed-Integer Nonlinear Programming Visualization Of Disassembly Sequence Planning Under Uncertainty, Sara Behdad, Leif P. Berg, Deborah Thurston, Judy M. Vance

Mechanical Engineering Publications

Disassembly sequence planning at the early conceptual stage of design leads to enormous benefits including simplification of products, lower assembly and disassembly costs, and design modifications which result in increased potential profitability of end-of-life salvaging operations. However, in the early design stage, determining the best disassembly sequence is challenging. First, the required information is not readily available and very time-consuming to gather. In addition, the best solution is sometimes counterintuitive, even to those with experience and expertise in disassembly procedures. Integrating analytical models with immersive computing technology (ICT) can help designers overcome these issues. A two-stage procedure for doing so ...


On-Chip Development Of Hydrogel Microfibers From Round To Square/Ribbon Shape, Zhenhua Bai, Janet M. Mendoza Reyes, Reza Montazami, Nicole Nastaran Hashemi Jan 2014

On-Chip Development Of Hydrogel Microfibers From Round To Square/Ribbon Shape, Zhenhua Bai, Janet M. Mendoza Reyes, Reza Montazami, Nicole Nastaran Hashemi

Mechanical Engineering Publications

We use a microfluidic approach to fabricate gelatin fibers with controlled sizes and cross-sections. Uniform gelatin microfibers with various morphologies and cross-sections (round and square) are fabricated by increasing the gelatin concentration of the core solution from 8% to 12%. Moreover, the increase of gelatin concentration greatly improves the mechanical properties of gelatin fibers; the Young's modulus and tensile stress at break of gelatin (12%) fibers are raised about 2.2 and 1.9 times as those of gelatin (8%) fibers. The COMSOL simulations indicate that the sizes and cross-sections of the gelatin fibers can be tuned by using ...


Engineering Fluid Flow Using Sequenced Microstructures, Hamed Amini, Elodie Sollier, Mahdokht Masaeli, Yu Xie, Baskar Ganapathysubramanian, Howard A. Stone, Dino Di Carlo May 2013

Engineering Fluid Flow Using Sequenced Microstructures, Hamed Amini, Elodie Sollier, Mahdokht Masaeli, Yu Xie, Baskar Ganapathysubramanian, Howard A. Stone, Dino Di Carlo

Mechanical Engineering Publications

Controlling the shape of fluid streams is important across scales: from industrial processing to control of biomolecular interactions. Previous approaches to control fluid streams have focused mainly on creating chaotic flows to enhance mixing. Here we develop an approach to apply order using sequences of fluid transformations rather than enhancing chaos. We investigate the inertial flow deformations around a library of single cylindrical pillars within a microfluidic channel and assemble these net fluid transformations to engineer fluid streams. As these transformations provide a deterministic mapping of fluid elements from upstream to downstream of a pillar, we can sequentially arrange pillars ...


Uniaxial Three-Dimensional Shape Measurement With Projector Defocusing, Ying Xu, Song Zhang Mar 2012

Uniaxial Three-Dimensional Shape Measurement With Projector Defocusing, Ying Xu, Song Zhang

Mechanical Engineering Publications

Our study shows that the phase error caused by improperly defocused binary structured patterns correlates to the depth z. This finding leads to a novel uniaxial three-dimensional shape measurement technique without triangulation. Since the measurement can be performed from the same viewing angle, this proposed method overcomes some limitations of the triangulation-based techniques, such as the problem of measuring deep holes. Our study explains the principle of the technique and presents some experimental results to verify its feasibility.


Fast-Framing Ballistic Imaging Of Velocity In An Aerated Spray, David Sedarsky, James Gord, Campbell Carter, Terrence R. Meyer, Mark Linne Sep 2009

Fast-Framing Ballistic Imaging Of Velocity In An Aerated Spray, David Sedarsky, James Gord, Campbell Carter, Terrence R. Meyer, Mark Linne

Mechanical Engineering Publications

We describe further development of ballistic imaging adapted for the liquid core of an atomizing spray. To fully understand spray breakup dynamics, one must measure the velocity and acceleration vectors that describe the forces active in primary breakup. This information is inaccessible to most optical diagnostics, as the signal is occluded by strong scattering in the medium. Ballistic imaging mitigates this scattering noise, resolving clean shadowgram-type images of structures within the dense spray region. We demonstrate that velocity data can be extracted from ballistic images of a spray relevant to fuel-injection applications, by implementing a simple, targeted correlation method for ...


Broadband Measurement Of Rate-Dependent Viscoelasticity At Nanoscale Using Scanning Probe Microscope: Poly(Dimethylsiloxane) Example, Zhonghua Xu, Kyongsoo Kim, Qingze Zou, Pranav Shrotriya Sep 2008

Broadband Measurement Of Rate-Dependent Viscoelasticity At Nanoscale Using Scanning Probe Microscope: Poly(Dimethylsiloxane) Example, Zhonghua Xu, Kyongsoo Kim, Qingze Zou, Pranav Shrotriya

Mechanical Engineering Publications

A control approach to achieve nanoscale broadband viscoelasticmeasurement using scanning probe microscope(SPM) is reported. Current SPM-based force measurement is too slow to measure rate-dependent phenomena, and large (temporal) measurement errors can be generated when the sample itself changes rapidly. The recently developed model-less inversion-based iterative control technique is used to eliminate the dynamics and hysteresis effects of the SPM hardware on the measurements, enabling rapid excitation and measurement of rate-dependent material properties. The approach is illustrated by the mechanical characterization of poly(dimethylsiloxane) over a broad frequency range of three orders of magnitude (∼1 Hz to 4.5 KHz).


Comparison Of A Solvent-Free Tar Quantification Method To The International Energy Agency’S Tar Measurement Protocol, Ming Xu, Robert C. Brown, Glenn A. Norton, Jerod Smeenk Jan 2005

Comparison Of A Solvent-Free Tar Quantification Method To The International Energy Agency’S Tar Measurement Protocol, Ming Xu, Robert C. Brown, Glenn A. Norton, Jerod Smeenk

Mechanical Engineering Publications

This paper presents a new method for measuring tar concentration in biomass-derived producer gas streams. This solvent-free method is much simpler than the evaporative method of the International Energy Agency (IEA) tar protocol. In tests on producer gas from a fluidized bed biomass gasifier this so-called dry condenser method yielded tar measurements with precision better than 5% and accuracy averaging to within 10% of the IEA tar protocol. Comparisons of water vapor concentrations in producer gas as determined by the two methodologies showed poor agreement, which appears to be due to the low precision of both techniques for this measurement ...