Digital Commons Network^™

Interaction Of Whey Protein With Modified Stainless Steel Surfaces, S.S. Premathilaka, M.M. Hyland, X.D. Chen, L.R. Watkins, B. Bansal

Heat Exchanger Fouling and Cleaning VII

Modified stainless steel surfaces were fouled with whey protein solutions to study the deposition mechanisms and the effects of surface modification. Stainless steel samples were coated with diamond-like carbon (DLC) and titanium nitride (TiN). These surfaces are expected to present different surface chemistries to stainless steel in terms of their functional groups and hydrophobic or hydrophilic nature. Thus, it is expected that foulant-surface interactions will differ for the various fouled surfaces. The substrates were exposed to a flowing whey protein solution in a fouling rig designed to achieve laminar flow. X-ray Photoelectron Spectroscopy (XPS) was used to study the initial …

Surface Treatment For The Mitigation Of Whey Protein Fouling, W. Augustin, T. Geddert, S. Scholl

Heat Exchanger Fouling and Cleaning VII

Heat transfer fouling experiments were carried out in a temperature controlled stirred vessel using aqueous solutions of whey protein concentrate in the concentration range of 3 to 3.5 wt-% at a bulk temperature of 50 °C and pH of 6. Heat transfer data were obtained from thermocouples embedded in an immersed electrical heating rod with various metal plates attached with-and-without surface treatments. Measurements included solution temperature, heating element surface temperature, and heat duty. Results are presented as fouling resistance versus time for aluminum, copper, stainless steel, electro-polished stainless steel, and surfaces coated with DLC and doped with Si , SiO, …

Experiments And Modelling Of Calcium Sulphate Precipitation Under Sensible Heating Conditions: Initial Fouling And Bulk Precipitation Rate Studies, F. Fahiminia, A. P. Watkinson, N. Epstein

Heat Exchanger Fouling and Cleaning VII

Crystallization of calcium sulphate, an inverse solubility salt, on a heated surface under sensible heating conditions has been studied. A temperature measurement technique was employed to detect initial fouling rates. Fouling experiments were carried out to determine how process variables such as surface temperature and velocity affect the initial fouling rates of calcium sulphate scaling. Experimental results show that, at a given surface temperature, there exists a maximum initial fouling rate for a range of fluid velocities. Also, this maximum rate and the fluid velocity at which it occurs both increase as the surface temperature increases. These observations are all …

Fouling Mechanisms By Ab Initio Calculations Condensation Reactions On The Rutile (101) Surface And Adsorption Of Ions On The Cr2o3 Surfaces, E. Puhakka, M. Riihimäki, R.L. Keiski

Heat Exchanger Fouling and Cleaning VII

Molecular modelling approach was utilized to describe detailed fouling mechanism caused by crystallization. The interest was on the heat transfer surfaces, which were manufactured from titanium and stainless steel. With ab initio calculations, the role of the surface oxide layer structure of titanium and stainless steel on fouling was investigated. The surface structure of titanium and stainless steel were assumed to consist of rutile (TiO2) and dichromium trioxide (Cr2O3), respectively. It was found that the inorganic fouling depends strongly on the oxide layer structure and the existence of hydroxyl groups on the surface. Based on the results, two mechanistically different …

Fouling During The Use Of ‘Fresh’ Water As Coolant- The Development Of A ‘User Guide’, S. J. Pugh, G. F. Hewitt, H. Müller-Steinhagen

Heat Exchanger Fouling and Cleaning VII

IHS ESDU recently published its latest ‘User Guide’ to fouling in heat exchange systems, for systems with fresh water as the coolant. ESDU 07006 [1] is the third in a group, following the development of the Crude Oil Fouling User Guide [2] issued in 2000 and the Seawater Fouling User Guide [3] issued in 2004. ESDU 07006 was developed by IHS ESDU over a period of five years under the guidance of the Oil Industry Fouling Working Party, a collaborative team of oil refiners, heat transfer equipment and services suppliers and Universities. It provides designers and operators of cooling water …

Achievements And Potential Of Self-Cleaning Heat Exchangers Using Untreated Natural Seawater As A Coolant, D.G. Klaren, E.F. De Boer

Heat Exchanger Fouling and Cleaning VII

The fluidized bed self-cleaning heat exchange technology has been developed in the 70s for the application in thermal desalination plants, like Multi-Stage Flash (MSF) evaporators. This paper summarizes the achievements of the Multi-Stage Flash / Fluidized Bed Evaporator (MSF/FBE) in the past, but also pays attention to its market potential today, whether or not in combination with the possible revamp of existing conventional MSF plants into a better performing configuration. Further, this paper also pays attention to the application of the self-cleaning heat exchange technology for closedloop coolers or so-called ‘mother-coolers’ for large chemical plants. Last but not least, attention …

Hitran® Wire Matrix Inserts In Fouling Applications, J.M. Ritchie, P. Droegemueller, M.J.H. Simmons

Heat Exchanger Fouling and Cleaning VII

Fouling characteristics are dictated largely by the properties of the thermal and hydrodynamic boundary layers. As a result, fouling mitigation strategies must take into account the conditions in this region. hiTRAN® wire matrix tube inserts are a useful tool in altering the conditions near the tube wall, especially in the laminar and transition flow regions. This review paper considers Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) measurements, which were employed in order to show the hydrodynamic differences between plain tubes and those containing inserts. Measurements indicate that the wall shear rate in tubes containing hiTRAN® inserts operating in …

Biofouling Control In Heat Exchangers Using High Voltage Capacitance Based Technology, R. Romo, M. M. Pitts, N. B. Handagama

Heat Exchanger Fouling and Cleaning VII

Biofouling in industrial heat exchangers and piping systems is common in water from all sources. Problems generated by biofouling such as corrosion, sludge deposition and scale formation have a costly impact on industrial equipment and productivity. This paper describes an electronic approach using High Voltage Capacitance Based technology (HVCB) to control biofouling in industrial heat exchangers, focusing upon biofilm removal and the prevention of biofilm formation. Four different application case studies are presented in this paper in which the HVCB technology was used to control biofouling. The applications include an evaporative cooling wall in a greenhouse in Oracle, Arizona; a …

Santa Clara Magazine, Volume 49 Number 1, Summer 2007, Santa Clara University

Santa Clara Magazine

8 - A CENTURY OF BRONCO BASKETBALL, By Jed Mettee and Steven Boyd Saum. Celebrating the first hundred seasons.

12 - A FAMILY SHOW By Steven Boyd Saum. Meet new men's basketball coach Kerry Keating.

14 - A SPACE THAT TALKS TO NATURE By Miriam Schulman. A team of SCU students aim to win the Department of Energy's Solar Decathlon. And save the planet.

19 - EPITAPH FOR THE JOURNEY A poem by Paul Mariani.

22 - THE BUZZ ABOUT SUSTAINABILITY By John Farnsworth. When we talk about "sustainability," what are we really talking about?

26 - THE GREEN TAX …

The Gravity Data Ontology: Laying The Foundation For Workflow-Driven Ontologies, Ann Q. Gates, G. Randy Keller, Flor Salcedo, Paulo Pinheiro Da Silva, Leonardo Salayandia

Departmental Technical Reports (CS)

A workflow-driven ontology is an ontology that encodes discipline-specific knowledge in the form of concepts and relationships and that facilitates the composition of services to create products and derive data. Early work on the development of such an ontology resulted in the construction of a gravity data ontology and the categorization of concepts: "Data," "Method," and "Product." "Data" is further categorized as "Raw Data" and "Derived Data," e.g., reduced data. The relationships that are defined capture inputs to and outputs from methods, e.g., derived data and products are output from methods, as well as other associations that are related to …

Bacterial And Protein Adhesion On Ni-P-Ptfe Coated Surfaces, Q. Zhao, C. Liu, Y. Liu, S. Wang

Heat Exchanger Fouling and Cleaning VII

The adhesion of bacteria and proteins on the surfaces of heat exchangers and food processing equipment has been recognized as a widespread problem. Biofouling not only reduces heat transfer performance significantly, but also causes considerable pressure drop, calling for higher pumping requirements. Biofouling also present a considerable hygiene risk in the food industry. It would be much more desirable if surfaces with an inherently lower stickability for biofouling could be developed. In this paper, stainless steel 304 plates were modified by electroless plating Ni-P and small amounts of PTFE. The experimental results showed that the surface free energy of the …

Global-Change Scenarios: Their Development And Use, Edward Parson, Virginia Burkett, Karen Fisher-Vanden, David Keith, Linda Mearns, Hugh Pitcher, Cynthia Rosenzweig, Mort Webster

United States Department of Energy: Publications

A scenario is a description of potential future conditions produced to inform decision-making under uncertainty. Scenarios can help inform decisions that involve high stakes and poorly characterized uncertainty, which may thwart other, conventional forms of analysis or decision support. Originally developed to study military and security problems, scenarios are now widely used for strategic planning and assessment in businesses and other organizations, and increasingly to inform planning, analysis, and decision-making for environmental issues, including climate change.
Scenarios can serve many purposes. They can help inform specific decisions, or can provide inputs to assessments, models, or other decision-support activities when these …

Scenarios Of Greenhouse Gas Emissions And Atmospheric Concentrations, Leon Clarke, James Edmonds, Henry Jacoby, Hugh Pitcher, John Reilly, Richard Richels

United States Department of Energy: Publications

This and a companion report constitute one of twenty-one Synthesis and Assessment Products called for in the Strategic Plan for the U.S. Climate Change Science Program. These studies are structured to provide high-level, integrated research results on important science issues with a particular focus on questions raised by decision-makers on dimensions of climate change directly relevant to the U.S. One element of the CCSP’s strategic vision is to provide decision support tools for differentiating and evaluating response strategies. Scenario-based analysis is one such tool. The scenarios in this report explore the implications of alternative stabilization levels of anthropogenic greenhouse …

A Finite Difference Method For Studying Thermal Deformation In A Three-Dimensional Microsphere Exposed To Ultrashort-Pulsed Lasers, Xudong Du

Doctoral Dissertations

Ultrashort-pulsed lasers with pulse durations on the order of sub-picoseconds to femtoseconds possess the capabilities in limiting the undesirable spread of the thermal process zone in a heated sample which have been attracting worldwide interest in science and engineering. Success of ultrashort-pulsed lasers in real application relies on: (1) well characterized pulse width, intensity and experimental techniques; (2) reliable microscale heat transfer models; and (3) prevention of thermal damage. Laser damage by ultrashort-pulsed lasers occurs after the heating pulse is over since the pulse duration time is extremely short and the heat flux is essentially limited to the region within …

Fabrication And Application Of Conducting Polymer Micro- And Nano-Patterns, Anirban Chakraborty

Doctoral Dissertations

Conducting polymers, since their discovery, have attracted significant attention due to their promise of replacing silicon and metals in building devices. They have been shown to have wide applications for biological and chemical sensing as well as for electronic devices. Previous and current efforts have concentrated on building devices of a specific function. When multiple micropatterns of different conducting polymers are fabricated on a common substrate, a versatile microsystem can be envisioned. The existing conducting polymer patterning techniques present some technical challenges of degradation, low throughput, low resolution, depth of field, and residual layer in producing conducting polymer microstructures. To …

The Effects Of Foreign Accent And Language On Reaction Time And Accuracy In An Air Traffic Control Task, Rosabelle Suarez

Master's Theses - Daytona Beach

The present study examines the effect of foreign accent interference with the ability to execute commands presented in speech format. The objective of this study was to demonstrate that a foreign accent influences performance. Participants were between 18 and 40 years of age. Half of the participants were native speakers of Spanish who began learning English as a second language via the classroom setting. The other half were native English-speaking with little or no exposure to the Spanish language. The experimental design was similar to an aviation scenario where participants listened to simulated ATC procedural commands and execute them on …

Love Canal Tragedy, Alicia Saunte Phillips, Yung-Tse Hung, Paul A. Bosela

Civil and Environmental Engineering Faculty Publications

The purpose of this environmental failure case study paper is to provide educational materials for environmental engineering courses dealing with design and operation of landfills for hazardous waste. In 1978, it was discovered that hazardous waste had contaminated homes and schools in the Love Canal area, a former chemical landfill which became a 15 acre neighborhood of the City of Niagara Falls, New York. On August 7, 1978, the United States President Jimmy Carter declared a federal emergency at the Love Canal. The Love Canal became the first man-made disaster to receive such a designation based on a variety of …

Nebraska Blueprint - Summer 2007

Nebraska Blueprint (Student Publication)

Table of Contents:

Engineering Alumni Join Peace Corps: Volunteers give back to society by teaching others applicable engineering skills. by Natasha Richardson
Graduate’s Career Lets him Explore Sea and Space: Don Skoumal has notable achievements and involvement in NASA’s Sea Launch Project. by Brian Neilson
Applying Nanotechnology to Tanks: Dean David Allen’s research is helping make tanks lighter and stronger. by Kellie Troxel
A Treatment for Hemophilia Could Start Here: Researchers look for a new treatment to combat this dangerous blood disorder. by Michaela McBride
10 Ways to Get the Most out of Engineering at UNL: A soon-to-be graduate gives …

Nonlinear Dynamical Analysis Of Brain Electrical Activity Due To Exposure To Weak Environmentally Relevant Electromagnetic Fields, Erik Alfonso Nilsen

Doctoral Dissertations

The reports dealing with the effects of weak electromagnetic fields (EMFs) on brain electrical activity have been inconsistent. We suspected that the use of linear models and their associated methods accounted for some of the variability, and we explored the issue by using a novel approach to study the effects of EMFs on the electroencephalogram (EEG) from rabbits and humans. The EEG was embedded in phase space and local recurrence plots were calculated and quantified to permit comparisons between exposed and control epochs from individual subjects. Statistically significant alterations in brain activity were observed in each subject when exposed to …

Rational Design And Investigation Of Polypeptide Multilayer Films And Capsules, Ling Zhang

Doctoral Dissertations

Three major concerns in the science of materials today are control over structure and function at the molecular level, biodegradability, and scalability of production. Polymeric materials, notably polyelectrolyte multilayer films, have shown considerable promise in all these areas, and for rational development of multifunctionality. Polypeptides constitute an especially interesting class of polyelectrolyte, given their inherent biodegradability, means of control over structure, methods of large-scale synthesis, and ability to encode biological information. Relatively little is known, however, about polypeptide multilayer films, despite recent advances in the general area.

In this dissertation, ten heteropolypeptides were designed and synthesized by Fmoc chemistry. These …

Information Consensus And Its Application In Multi-Vehicle Cooperative Control, Ella Atkins, Randal Beard, Wei Ren

Faculty Publications

In the last two decades, advances in networking and distributed computing have facilitated a paradigm shift from large, monolithic mainframe computers to networks of less expensive, less powerful workstations. One motivation for multi-vehicle systems is to achieve the same gains for mechanically controlled systems as has been gained in distributed computation. Rather than having a single monolithic (and therefore expensive and complicated) machine do everything, the hope is that many inexpensive, simple machines, can achieve the same, or enhanced functionality, through coordination. In essence, the objective is to replace expensive complicated hardware with software and multiple copies of simple hardware. …

Intelligent Local And Hierarchical Control Of Facts Devices, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an overview of the applications of intelligent control techniques on local and hierarchical control of FACTS devices. These control techniques are superior to the conventional linear/nonlinear control schemes in the sense that they are independent of any mathematical model of the power system to be controlled. In addition, they do not depend on the operating conditions and the configuration of the system to which the FACTS device is connected. A static compensator (STATCOM) is used as the example in order to compare the performances of the proposed intelligent controllers with those of their linear counterparts. Nevertheless, the …

Method Of Measuring Permittivity Of Composite Materials With Hexagonal Ferrite Inclusions, Alexander A. Kitaytsev, Gulnur N. Zhumabayeva, Marina Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

A new simple method for measuring complex permittivity of substantially lossy composite materials is presented. In this method, a sample of the material under study should completely fill in the cross-section of the single-mode transmission line (waveguide), and the length of the sample must be an integer of a half-wavelength in the waveguide filled with this material. The oscillator frequency is swept linearly, the minima of the reflection coefficient are measured, and then analytical formulas are used to calculate real and imaginary parts of permittivity. The method was tested on magneto- dielectric samples containing hexagonal ferrite powders, as well on …

Virginia Junior Academy Of Science Awards, 2007

Virginia Journal of Science

Virginia Junior Academy of Science Awards Presented During the 66th Annual Meeting at James Madison University, Harrisonburg, Virginia, May 23-25, 2007.

Rotorcraft Smoothing Via Linear Time Periodic Methods, Christopher S. Schulz

Theses and Dissertations

This research presents the development of an on line linear time periodic rotor vibration controller. The Cramer-Rao bound is developed for a linear time periodic system in order to identify the quality of identified system parameters, which are used in system models for controller development. The methods developed in this work allow model parameters can be verified for accuracy and likewise adjusted to improve controller accuracy.

Cooperative Uav Formation Flying With Obstacle/Collision Avoidance, Xiaohua Wang, Vivek Yadav, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Navigation problems of unmanned air vehicles (UAVs) flying in a formation in a free and an obstacle-laden environment are investigated in this brief. when static obstacles popup during the flight, the UAVs are required to steer around them and also avoid collisions between each other. In order to achieve these goals, a new dual-mode control strategy is proposed: a “safe mode” is defined as an operation in an obstacle-free environment and a “danger mode” is activated when there is a chance of collision or when there are obstacles in the path. Safe mode achieves global optimization because the dynamics of …

Water Erosion Prediction Project (Wepp): Development History, Model Capabilities, And Future Enhancements, Dennis C. Flanagan, John E. Gilley, Thomas G. Franti

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Water Erosion Prediction Project (WEPP) was initiated in August 1985 to develop new‐generation water erosion prediction technology for use by federal action agencies involved in soil and water conservation and environmental planning and assessment. Developed by the USDA‐ARS as a replacement for empirically based erosion prediction technologies, the WEPP model simulates many of the physical processes important in soil erosion, including infiltration, runoff, raindrop and flow detachment, sediment transport, deposition, plant growth, and residue decomposition. The WEPP project included an extensive field experimental program conducted on cropland, rangeland, and disturbed forest sites to obtain data required to parameterize and …

Analyses Of Internal Solitary Waves Generated At The Columbia River Plume Front Using Sar Imagery, Jiayi Pan, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Internal solitons generated at the Columbia River plume front during ebb tide are displayed on a synthetic aperture radar (SAR) image taken on 26 July 2004 at 14:24:22 UTC. Scale analyses suggest that these internal solitons belong to the finite-depth category. A theoretical model, relating the radar backscatter cross section to dynamic parameters of internal solitons in the continuous stratification, is developed. Using the model and background stratification data collected by the River Influences on Shelf Ecosystem (RISE) project in July 2004, we extract the soliton dynamic parameters of the half-width, amplitude, phase speed, and average energy flux per crest …

Simulations Of Intracellular Calcium Release In Response To High-Intensity, Ultrashort Electric Pulse, Anh Nguyen

Electrical & Computer Engineering Theses & Dissertations

Calcium modulation is an important signaling process and could even contribute to cell apoptosis through ionic-induced perturbations in trans-membrane potential at the mitochondria. In this research, the numerical study constitutes a first step in quantitatively probing the time- and spatially-dependent modulation of calcium dynamics through the application of external electrical fields. The research uses both widely accepted deterministic continuum and discrete stochastic intracellular calcium models coupling with external electric field, with a focus on high-intensity ultrashort pulse electrical field.

For deterministic continuum intracellular calcium models with electric field assisted, numerical simulations for electrically induced, intra-cellular calcium-release from the endoplasmic reticulum …

Old Dominion University Space Systems Engineering Competency Development To Accommodate Orbital Flight Projects, Ersin Ancel

Mechanical & Aerospace Engineering Theses & Dissertations

Undergraduate engineering students in Old Dominion University's Batten College of Engineering and Technology have been engaged in the design, development, testing and flight of scientific sounding rocket payloads since 2004. During that time, two payloads have flown and a third payload has nearly achieved flight-ready status. The sophistication achieved by the flight-ready payload has resulted from the evolution of a rather rigorous space system design process that requires student involvement over periods of time that are much longer than those typically associated with an -undergraduate design course sequence.

In order to acquire the expected level of definition and reliability for …