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A Macrobending Singlemode Fiber Refractive Index Sensor For Low Refractive Index Liquids, Pengfei Wang, Yuliya Semenova, Yong Li, Qiang Wu, Gerald Farrell 2010 Technological University Dublin

A Macrobending Singlemode Fiber Refractive Index Sensor For Low Refractive Index Liquids, Pengfei Wang, Yuliya Semenova, Yong Li, Qiang Wu, Gerald Farrell

Articles

An all-fiber refractive index sensor with a simple configuration is proposed and investigated. The proposed fiber refractometer consists of a full-loop structure of bare high-bend loss singlemode fiber-1060XP, employing the well-known whispering gallery mode (WGM) effect induced by the evanescent wave excitation to measure the refractive index of an external medium. A competitive sensitivity is achieved (average 725.76nm/RIU at a bend diameter of 19.3mm) compared with other fiber-optic sensors, plus benefits resulting from simplicity, low cost and ease of fabrication.


Concurrent Masters Degrees Across The Atlantic: Innovations, Issues And Insights, Michael Dyrenfurth, Mike Murphy, Gary Bertoline, Robert Herrick, Kathryne Newton, Gareth O'Donnell, Donal McHale, Nuria Castell, Miquel Barcelo, Didac Balas, Maria Ribera Sancho, Jordi Garcia 2010 Purdue University

Concurrent Masters Degrees Across The Atlantic: Innovations, Issues And Insights, Michael Dyrenfurth, Mike Murphy, Gary Bertoline, Robert Herrick, Kathryne Newton, Gareth O'Donnell, Donal Mchale, Nuria Castell, Miquel Barcelo, Didac Balas, Maria Ribera Sancho, Jordi Garcia

Conference papers

Atransatlantic degree consortium to implement a four-semester dual masters degree initiative across a three-institution consortium consisting of Purdue University (USA), the Dublin Institute of Technology (DIT), and the Universitat Politècnica de Catalunya (Spain) is presented in this paper.


Quality Indicators For Engineering And Technology Education, Michael Dyrenfurth, Mike Murphy, Gary Bertoline 2010 Purdue University

Quality Indicators For Engineering And Technology Education, Michael Dyrenfurth, Mike Murphy, Gary Bertoline

Conference papers

In recent years the development and use of university rankings, comparisons, and/or league tables has become popular and several methodologies are now frequently used to provide a comparative ranking of universities. These rankings are often based on research and publication activity and also not uncommonly focus on indicators that can be measured rather than those that should be measured. Further, the indicators are generally examined for the university as a whole rather than for university divisions, departments or programs. Implicit also is that placement in the rankings is indicative of quality. This paper provides an overview of the methodologies ...


Intergrain Connectivity Of Mgb2 Ceramics Studied By Impedance Analysis, C.C Wang, C Wang, Rong Zeng, S X. Dou 2010 ISEM

Intergrain Connectivity Of Mgb2 Ceramics Studied By Impedance Analysis, C.C Wang, C Wang, Rong Zeng, S X. Dou

Australian Institute for Innovative Materials - Papers

First, by using of the conventional Rowell analysis, we demonstrated that the addition of nano BN particles can effectively eliminate MgO and pores in MgB2 resulting in a very high density and good connectivity of BN-doped MgB2. Then, another method—low-frequency dielectric impedance analysis—was introduced to characterize the properties of the grain boundaries of MgB2. A comparative impedance study was performed in the frequency range from 100 Hz to 100 MHz on pure and nano BN-doped MgB2. The study revealed some following interesting results: (1) a dielectric resonance around frequency of 108 in both samples ...


Effect Of Electrical Double Layer On Electric Conductivity And Pressure Drop In A Pressure-Driven Microchannel Flow, Heng Ban, Bochuan Lin, Zhourui Song 2010 Utah State University - Faculty Advisor

Effect Of Electrical Double Layer On Electric Conductivity And Pressure Drop In A Pressure-Driven Microchannel Flow, Heng Ban, Bochuan Lin, Zhourui Song

Mechanical and Aerospace Engineering Faculty Publications

The effect of an electrical double layer (EDL) on microchannel flow has been studied widely, and a constant bulk electric conductivity is often used in calculations of flow rate or pressure drop. In our experimental study of pressure-driven micropipette flows, the pipette diameter is on the same order of magnitude as the Debye length. The overlapping EDL resulted in a much higher electric conductivity, lower streaming potential, and lower electroviscous effect. To elucidate the effect of overlapping EDL, this paper developed a simple model for water flow without salts or dissolved gases (such as CO2) inside a two-dimensional microchannel ...


A Comparison Of Hemodynamic Performance In Mehcanical And Biological Heart Valve Prostheses, Philip Mathew 2010 University of Tennessee at Chattanooga

A Comparison Of Hemodynamic Performance In Mehcanical And Biological Heart Valve Prostheses, Philip Mathew

Masters Theses and Doctoral Dissertations

Heart valve prostheses are used to replace heart valves in patients afflicted with valvular heart disease. The malfunctioning heart valve adversely affects the fluid mechanical performance. While the choice of mechanical VS biological valve prostheses is dependent on the patient, the biological valves should have improved hemodynamic performance compared to the mechanical valves. This work focused on CFD analysis of the Starr-Edwards caged ball valve and a biological valve and serves to validate the improved hemodynamics of the latter valve in comparison to the former. Commercial CFD software (CFD-GEOM, CFD-ACE, CFD-VIEW) are used for the analys is. The main results ...


Strategies For Lidar Characterization Of Particulates From Point And Area Sources, Michael D. Wojcik, Kori D. moore, Randy Martin, Jerry Hatfield 2010 Utah State University

Strategies For Lidar Characterization Of Particulates From Point And Area Sources, Michael D. Wojcik, Kori D. Moore, Randy Martin, Jerry Hatfield

Civil and Environmental Engineering Faculty Publications

Use of ground based remote sensing technologies such as scanning lidar systems (light detection and ranging) has gained traction in characterizing ambient aerosols due to some key advantages such as wide area of regard (10 km2 ), fast response time, high spatial resolution (m) and high sensitivity. Energy Dynamics Laboratory and Utah State University, in conjunction with the USDA-ARS, has developed a three-wavelength scanning lidar system called Aglite that has been successfully deployed to characterize particle motion, concentration, and size distribution at both point and diffuse area sources in agricultural and industrial settings. A suite of massbased and size distribution point ...


The Development Of A Mesenchymal Stem Cell Based Biphasic Osteochondral Tissue Engineered Construct, Scott Maxson 2010 Clemson University

The Development Of A Mesenchymal Stem Cell Based Biphasic Osteochondral Tissue Engineered Construct, Scott Maxson

All Dissertations

The ability of human articular cartilage to respond to injury is poor. Once cartilage damage has occurred, an irreversible degenerative process can occur and will often lead to osteoarthritis (OA). An estimated 26.9 million of U.S. adults are affected by OA. Osteochondral grafting is currently used to treat OA and osteochondral defects; however, complications can develop at the donor site and defect area. Osteochondral tissue engineering provides a potential treatment option and alternative to osteochondral grafting. The long term goal of this work is to develop a tissue engineered mesenchymal stem cell (MSC) based osteochondral construct to repair ...


Initial Expansion Of The Columbia River Tidal Plume: Theory And Remote Sensing Observations, David A. Jay, Edward D. Zaron, Jiayi Pan 2010 Portland State University

Initial Expansion Of The Columbia River Tidal Plume: Theory And Remote Sensing Observations, David A. Jay, Edward D. Zaron, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

Analysis of the Columbia River tidal plume using Lagrangian frontal equations provides a concise description of the evolution of frontal depth H, velocity U, reduced gravity g', and frontal internal Froude number F (sub R) . Because the estuary mouth is narrow, the initial radial plume motion is supercritical (F (sub R) > 1) for up to 12 hours. Understanding this supercritical phase is vital, because plume properties change rapidly, with strong ecosystem impacts. To analyze this expansion, analytical and numerical models (the latter with three mixing formulations) were tested. Model results are compared to synthetic aperture radar images to verify that ...


Microstructure Investigations Of Pt-Modified Γ′-Ni3al + Γ-Ni Coatings On Ni-Based Superalloys, Guanghui Cao, Taoping Ou, Hua Jiang, Alan M. Russell 2010 Shanghai University

Microstructure Investigations Of Pt-Modified Γ′-Ni3al + Γ-Ni Coatings On Ni-Based Superalloys, Guanghui Cao, Taoping Ou, Hua Jiang, Alan M. Russell

Materials Science and Engineering Publications

The microstructure of Pt-modified γ′-Ni3Al + γ-Ni coating on CMSX-4 single-crystal superalloy has been investigated by transmission electron microscopy (TEM). Cross-sectional TEM analyses showed the presence of precipitates in the coating. This precipitate was identified as the hexagonal topologically close-packed (TCP) μ phase with lattice parameters a = 0.473 nm and c = 2.565 nm. The energy-dispersive x-ray (EDX) spectrum of the μ phase suggested a refractory element rich compound comprising the elements Re, W, and Co. Twin domains parallel to (001) were found in the μ phase. The mechanisms of the μ phase and twinning formation were ...


Robust Dynamic Balance Of Ap-1 Transcription Factors In A Neuronal Gene Regulatory Network., Gregory M Miller, Babatunde A Ogunnaike, James S Schwaber, Rajanikanth Vadigepalli 2010 Thomas Jefferson University

Robust Dynamic Balance Of Ap-1 Transcription Factors In A Neuronal Gene Regulatory Network., Gregory M Miller, Babatunde A Ogunnaike, James S Schwaber, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The octapeptide Angiotensin II is a key hormone that acts via its receptor AT1R in the brainstem to modulate the blood pressure control circuits and thus plays a central role in the cardiac and respiratory homeostasis. This modulation occurs via activation of a complex network of signaling proteins and transcription factors, leading to changes in levels of key genes and proteins. AT1R initiated activity in the nucleus tractus solitarius (NTS), which regulates blood pressure, has been the subject of extensive molecular analysis. But the adaptive network interactions in the NTS response to AT1R, plausibly related to the development of ...


Semicrystalline Woodpile Photonic Crystals Without Complicated Alignment Via Soft Lithography, Jae-Hwang Lee, Ping Kuang, Wai Y. Leung, Yong-Sung Kim, Joong Mok Park, Henry Kang, Kristen P. Constant, Kai-Ming Ho 2010 Iowa State University

Semicrystalline Woodpile Photonic Crystals Without Complicated Alignment Via Soft Lithography, Jae-Hwang Lee, Ping Kuang, Wai Y. Leung, Yong-Sung Kim, Joong Mok Park, Henry Kang, Kristen P. Constant, Kai-Ming Ho

Materials Science and Engineering Publications

We report the fabrication and characterization of woodpile photonic crystals with up to 12 layers through titania nanoparticle infiltration of a polymer template made by soft lithography. Because the complicated alignment in the conventional layer-by-layer fabrication associated with diamondlike symmetry is replaced by a simple 90° alignment, the fabricatedphotonic crystal has semicrystalline phase. However, the crystal performs similarly to a perfectly aligned crystal for the light propagation integrated from the surface normal to 30° at the main photonic band gap.


Application Of A Combined Catalyst And Sorbent For Steam Reforming Of Methane, Karl O. Albrecht, Justinus A. Satrio, Brent H. Shanks, Thomas D. Wheelock 2010 Iowa State University

Application Of A Combined Catalyst And Sorbent For Steam Reforming Of Methane, Karl O. Albrecht, Justinus A. Satrio, Brent H. Shanks, Thomas D. Wheelock

Chemical and Biological Engineering Publications

The performance of a combined catalyst and sorbent material designed for reforming hydrocarbons was evaluated by reacting methane with steam at different temperatures and pressures in a reactor packed with the material. The combined material was in the form of small spherical pellets comprised of a sorbent core of lime encased in a porous shell made largely of sintered alumina that supported a nickel catalyst. On the basis of previous research, two shell formulations were included in the study. One shell formulation contained a small quantity of CaO for strengthening of the shells, whereas the other contained a similar quantity ...


Multiscale Modeling Of Tio2 Nanoparticle Production In Flame Reactors: Effect Of Chemical Mechanism, Maulik Mehta, Yonduck Sung, Venkatramanan Raman, Rodney O. Fox 2010 Iowa State University

Multiscale Modeling Of Tio2 Nanoparticle Production In Flame Reactors: Effect Of Chemical Mechanism, Maulik Mehta, Yonduck Sung, Venkatramanan Raman, Rodney O. Fox

Chemical and Biological Engineering Publications

For titanium dioxide (TiO2) nanoparticles manufactured in flame reactors, the precursor is injected into a pre-existing flame, exposing it to a high-temperature gas phase, leading to nucleation and particle growth. Predictive modeling of this chemical process requires simultaneous development of detailed chemical mechanisms describing gas-phase combustion and particle evolution, as well as advanced computational tools for describing the turbulent flow field and its interactions with the chemical processes. Here, a multiscale computational tool for flame-based TiO2 nanoparticle synthesis is developed and a flamelet model representing detailed chemistry for particle nucleation is proposed. The effect of different chemical mechanisms ...


Kinetic Modeling Of Nanoprecipitation Using Cfd Coupled With A Population Balance, Janine C. Cheng, Rodney O. Fox 2010 Iowa State University

Kinetic Modeling Of Nanoprecipitation Using Cfd Coupled With A Population Balance, Janine C. Cheng, Rodney O. Fox

Chemical and Biological Engineering Publications

A model study has been conducted for Flash Nanoprecipitation (FNP)sa novel approach to produce functional nanoparticles. A population balance equation with the FNP kinetics has been integrated into a computational fluid dynamics (CFD) simulation of a custom-designed microscale multi-inlet vortex reactor (MIVR) to yield conditions comparable to the real experimental settings. In coping with the complicated aggregation model in the CFD code, a new numerical approach, the conditional quadrature method of moments (CQMOM), has been proposed, which is capable of solving the multivariate system efficiently and accurately. It is shown that the FNP process is highly influenced by mixing ...


Combined Electrochemical Surface Plasmon Resonance For Angle Spread Imaging Of Multielement Electrode Arrays, Andrew C. Hillier, Chang Hoon Choi 2010 Iowa State University

Combined Electrochemical Surface Plasmon Resonance For Angle Spread Imaging Of Multielement Electrode Arrays, Andrew C. Hillier, Chang Hoon Choi

Chemical and Biological Engineering Publications

A surface plasmon resonance imaging system combined with a multielement electrode array is described. An optical system with shaping optics is used to direct a wedge of light onto a gold-coated sample. The reflected light is detected in the form of an angle-spread image of the surface, with one direction denoting a variable incident angle and the other showing a span of locations along one lateral direction of the sample surface. At the proper incident angle, the angle-spread image shows the complete surface plasmon resonance curve over a span of locations on the surface. This imaging system is combined with ...


Book Review: Controlled And Living Polymerizations: From Mechanisms To Applications, Jennifer M. Heinen 2010 Iowa State University

Book Review: Controlled And Living Polymerizations: From Mechanisms To Applications, Jennifer M. Heinen

Chemical and Biological Engineering Publications

Controlled/living polymerization makes it possible to synthesize polymers of low polydispersity with a predefined molecular weight and specified chain architecture. Such polymers are desirable for a broad range of applications, including coatings, adhesives, and lubricants. Although living polymerization was first discovered in anionic polymerizations in 1956, several decades passed prior to the development of living polymerization techniques for carbocationic polymerization (1984) and ring-opening metathesis polymerization (1986). During the 1990s, several techniques were developed for controlled/living free radical polymerizations. The development of these techniques led to a dramatic increase in the number of research publications dedicated to improving the ...


Effect Of Mesoporosity On Thermal And Mechanical Properties Of Polystyrene/Silica Composites, Melissa A. Ver Meer, Balaji Narasimhan, Brent H. Shanks, Surya K. Mallapragada 2010 Schlumberger Lawrence Technology Center

Effect Of Mesoporosity On Thermal And Mechanical Properties Of Polystyrene/Silica Composites, Melissa A. Ver Meer, Balaji Narasimhan, Brent H. Shanks, Surya K. Mallapragada

Chemical and Biological Engineering Publications

In this study, mesoporous or colloidal silica particles were incorporated into polystyrene matrices via melt blending or by styrene polymerization initiated from the particle surface. The relationships between the surface morphology of filler particles in polymer composites and their thermomechanical properties were investigated. High molecular weight polystyrene-silica hybrids were generated by modifying the surfaces of monodisperse colloidal silica and templated mesoporous silica nanoparticles. The functionalized silica surfaces were grafted with alkyl halide initiators for atom transfer radical polymerization. Polymerization was conducted without free initiator present. The physical properties of these composites were studied by dynamic mechanical analysis, thermogravimetric analysis, transmission ...


Micro-Recanalization In A Biodegradable Graft For Reconstruction Of The Vas Deferens Is Enhanced By Sildenafil Citrate, Peter A. Holoch, Surya K. Mallapragada, Carlos Atico Ariza, Thomas S. Griffith, Barry R. DeYoung, Moshe Wald 2010 University of Iowa

Micro-Recanalization In A Biodegradable Graft For Reconstruction Of The Vas Deferens Is Enhanced By Sildenafil Citrate, Peter A. Holoch, Surya K. Mallapragada, Carlos Atico Ariza, Thomas S. Griffith, Barry R. Deyoung, Moshe Wald

Chemical and Biological Engineering Publications

This study investigated the effect of sildenafil citrate on micro-recanalization and neovascularization, which were previously demonstrated in a rat model using biodegradable grafts (BGs) for vas deferens reconstruction. A total of 24 male rats underwent bilateral vasectomy with removal of a 0.5-cm vasal segment and were randomly assigned to four groups. Groups 1 and 2 underwent immediate vasovasostomy. Groups 3 and 4 underwent interposition of a 0.5-cm BG in the vasal gap. Groups 1 and 3 were given 5 mg kg -1 day -1 oral sildenafil. Other groups were given placebo. Rats were housed with females 12 weeks ...


Utilizing Multimedia Case Studies To Teach The Professional Side Of Project Management, Cassandra C. Elrod, Susan L. Murray, Barry B. Flachsbart, Karl E. Burgher, Drew M. Foth 2010 Missouri University of Science and Technology

Utilizing Multimedia Case Studies To Teach The Professional Side Of Project Management, Cassandra C. Elrod, Susan L. Murray, Barry B. Flachsbart, Karl E. Burgher, Drew M. Foth

Business and Information Technology Faculty Research & Creative Works

This research was conducted to evaluate the effectiveness of using a LITEE multimedia case study to teaching concepts in engineering courses. The LITEE Superstar case study was implemented in an engineering Project Management course. Numerous surveys regarding student expectations, outcomes, and attitudes were collected and results are presented herein. Overall, the study provided evidence that the students felt that the LITEE case study added value to the course via the different methods of teaching material, aided in the understanding of the project selection process, and ultimately helped them be successful in their course project which was conducted for a real ...


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