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2007

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Direct Formation Of H_2o_2 From H_2 And O_2, Meltem Yildiz, Ayşe Ni̇lgün Akin Jan 2007

Direct Formation Of H_2o_2 From H_2 And O_2, Meltem Yildiz, Ayşe Ni̇lgün Akin

Turkish Journal of Chemistry

The direct combination of hydrogen and oxygen to form hydrogen peroxide in liquid media with prepared catalysts was carried out in a slurry reactor at atmospheric pressure and room temperature. An O_2/H_2 ratio of 2:1 with a 50 mL/min flow rate was used in these experiments. Catalyst activity measurements were tested by the iodometric titration method using KMnO_4. The results are discussed based on the effects of support material, catalyst preparation method, reaction time, and medium (type of halide and acid) on hydrogen peroxide yield in direct oxidation of hydrogen to produce hydrogen peroxide. Our results showed that the catalytic …


Dielectric Behavior Of The Catalyst Zeolite Nay, Ertuğrul İzci̇, Ali̇me İzci̇ Jan 2007

Dielectric Behavior Of The Catalyst Zeolite Nay, Ertuğrul İzci̇, Ali̇me İzci̇

Turkish Journal of Chemistry

Zeolites are crystalline hydrated aluminosilicates of alkaline and alkaline earth metals. The basic zeolite structure is an anionic frame of Si and Al T-atoms, which are tetrahedral and coordinated with oxygen atoms. The electrical properties of zeolites are of enormous technical importance due to their manifold applications as solid catalysts. Zeolite NaY was used in this investigation. Zeolite NaY is a synthetic zeolite and it has a faujasite structure. The electrical conductivity, dielectric permittivity, and loss factor of Na ion exchanged zeolite NaY was carried out in the 10^4-10^6 Hz frequency region at room temperature and different water contents using …


Investigation Of Biodiesel Production From Canola Oil Using Mg-Al Hydrotalcite Catalysts, Oğuzhan İlgen, İsmai̇l Di̇nçer, Meltem Yildiz, Ertan Alpteki̇n, Nezahat Boz, Mustafa Çanakçi, Ayşe Ni̇lgün Akin Jan 2007

Investigation Of Biodiesel Production From Canola Oil Using Mg-Al Hydrotalcite Catalysts, Oğuzhan İlgen, İsmai̇l Di̇nçer, Meltem Yildiz, Ertan Alpteki̇n, Nezahat Boz, Mustafa Çanakçi, Ayşe Ni̇lgün Akin

Turkish Journal of Chemistry

Biodiesel produced by the transesterification of vegetable oils is a promising alternative fuel to diesel because of limited fossil fuel resources and environmental concerns. The use of heterogeneous catalysts greatly simplifies the technological process by facilitating the separation of the post-reaction mixture. The purpose of the present work was to examine a heterogeneous catalyst, in particular, Mg-Al hydrotalcites, to produce methyl esters of canola oil. In this study, the transesterification of canola oil with methanol was studied in a heterogeneous system, using Mg-Al hydrotalcites as solid base catalysts. The results showed that methanol is the best alcohol for this reaction …


Alcohols As Alternatives To Petroleum For Environmentally Clean Fuels And Petrochemicals, Ti̇mur Doğu, Di̇lek Varişli Jan 2007

Alcohols As Alternatives To Petroleum For Environmentally Clean Fuels And Petrochemicals, Ti̇mur Doğu, Di̇lek Varişli

Turkish Journal of Chemistry

In this review article, some of the challenging research areas related to the development of novel catalysts and catalytic processes for the chemical fixation of CO_2 by converting it to alcohols and ethers, and for the conversion of alcohols to olefins and other hydrocarbons are reviewed. Ethanol, methanol, and the ethers derived from them, such as DEE and DME, have good burning characteristics and may be considered attractive transportation fuel alternates. New processes for catalytic selective oxidation and dehydration of alcohols may open up new pathways for the production of olefins and other petrochemicals from non-petroleum feedstock. Developments in CO_2 …


Partial Separability And Partial Additivity For Orderings Of Binary Alternatives, Md. Abul Bashar Jan 2007

Partial Separability And Partial Additivity For Orderings Of Binary Alternatives, Md. Abul Bashar

Theses and Dissertations (Comprehensive)

In Multiple-Criteria Decision Analysis (MCDA), a good way to find the best alternative is to construct a value function that represents a Decision Maker’s (DM) preferences. For multidimensional alternatives, an additive value function is easiest to work with because it assesses the alternatives in a simple and transparent manner. A DM’s preferences over consequences on a subset of the set of criteria may or may not depend on consequences on the rest of the criteria. Preferences that are free from all such interdependence are said to be separable. The existence of an additive value function implies separability and, when consequences …


The Quest For Tenure-Track Faculty Positions By Community College Adjunct Faculty, Leandra Powell Martin Jan 2007

The Quest For Tenure-Track Faculty Positions By Community College Adjunct Faculty, Leandra Powell Martin

Doctoral Dissertations

unavailable


A Meta-Analysis Of Functional Behavioral Assessments Of Students With High-Incidence Disabilities In Public Education Settings, Jeff Gabrielson Jan 2007

A Meta-Analysis Of Functional Behavioral Assessments Of Students With High-Incidence Disabilities In Public Education Settings, Jeff Gabrielson

Doctoral Dissertations

unavailable


Development Of A Coupled Fluid/Structure Aeroelastic Solver With Applications To Vortex Breakdown-Induced Twin Tail Buffeting, Steven J. Massey Jan 2007

Development Of A Coupled Fluid/Structure Aeroelastic Solver With Applications To Vortex Breakdown-Induced Twin Tail Buffeting, Steven J. Massey

Mechanical & Aerospace Engineering Theses & Dissertations

Simulation of tail buffet is studied for several delta wing-vertical tail configurations. Flow conditions are chosen such that the wing primary-vortex cores experience vortex breakdown and the resulting turbulent wake flow impinges on the vertical tail. The dimensions and material properties of the vertical tails are chosen such that the deflections are large enough to insure interaction with the flow, and the natural frequencies are high enough to facilitate a practical computational solution. This multi-disciplinary problem is solved sequentially for the fluid flow, the elastic deformations and the grid displacements. The flow is simulated by time accurately solving the laminar, …


Digital Watermarking And Self-Authentication Using Chirp Coding, Jonathan Blackledge Jan 2007

Digital Watermarking And Self-Authentication Using Chirp Coding, Jonathan Blackledge

Articles

This paper discusses a new approach to ‘watermarking’ digital signals using linear frequency modulated or ‘chirp’ coding. The principles underlying this approach are based on the use of a matched filter to provide a reconstruction of a chirped code that is uniquely robust, i.e. in the case of very low signal-to-noise ratios.

Chirp coding for authenticating data is generic in the sense that it can be used for a range of data types and applications (the authentication of speech and audio signals, for example). The theoretical and computational aspects of the matched filter and the properties of a chirp are …


Modelling And Computer Simulation Of Radar Screening Using Plasma Clouds, Jonathan Blackledge Jan 2007

Modelling And Computer Simulation Of Radar Screening Using Plasma Clouds, Jonathan Blackledge

Articles

Following a brief introduction on the principles of screening an aerospace vehicle using a plasma, we develop models for the Impulse Response Functions (IRFs) associated with microwave (Radar) back-scattering from a strong and weakly ionized plasma screen. In the latter case, it is shown that the strength of the return signal is determined by an IRF that is characterised by the simple negative exponential exp(−σ0t/Є0) where σ0 is the average conductivity of the plasma, Є0 is the permittivity of free space and t is the two-way travel time. For a weakly ionized plasma, the …


Discontinuous Change In The Smectic Layer Thickness In Ferrielectric Liquid Crystals, V. P. Panov, J. K. Vij, Yuri Panarin, C. Blanc, V. Lorman, J. W. Goodby Jan 2007

Discontinuous Change In The Smectic Layer Thickness In Ferrielectric Liquid Crystals, V. P. Panov, J. K. Vij, Yuri Panarin, C. Blanc, V. Lorman, J. W. Goodby

Articles

The temperature dependence of the thickness of thick free-standing films is studied using a high-resolution film thickness measurement technique. A small discontinuity in the temperature dependence of the smectic layer thickness at every phase transition between ferro-, ferri-, and antiferroelectric phases is observed. We show that the major contribution to it arises from a change in the smectic tilt angle.


The Role Of Spontaneous Polarization And The Thickness Of Alignment Layers On The V-Shaped Switching In Flc Cells, V. Manjuladevi, J.K. Vij, Yuri Panarin Jan 2007

The Role Of Spontaneous Polarization And The Thickness Of Alignment Layers On The V-Shaped Switching In Flc Cells, V. Manjuladevi, J.K. Vij, Yuri Panarin

Articles

Ferroelectric liquid crystal mixtures with the various values of spontaneous polarizations were prepared, and the substrates were coated with different thicknesses of aligning agent. The frequency dependence of the electrooptic response of these materials in cells with various thickness of alignment layers has been measured. The coercive voltage as well as the contrast ratios are calculated. Our results support the ‘‘electrostatic model’’, according to which both the value of spontaneous polarization and the thickness of the alignment layer play important roles in the V-shaped switching.


Robustness Of Proxy-Based Climate Field Reconstruction Methods, Scott Rutherford, Michael E. Mann, Eugene Wahl, Caspar Ammann Jan 2007

Robustness Of Proxy-Based Climate Field Reconstruction Methods, Scott Rutherford, Michael E. Mann, Eugene Wahl, Caspar Ammann

Arts & Sciences Faculty Publications

We present results from continued investigations into the fidelity of covariance-based climate field reconstruction (CFR) approaches used in proxy-based climate reconstruction. Our experiments employ synthetic “pseudoproxy” data derived from simulations of forced climate changes over the past millennium. Using networks of these pseudoproxy data, we investigate the sensitivity of CFR performance to signal-to-noise ratios, the noise spectrum, the spatial sampling of pseudoproxy locations, the statistical representation of predictors used, and the diagnostic used to quantify reconstruction skill. Our results reinforce previous conclusions that CFR methods, correctly implemented and applied to suitable networks of proxy data, should yield reliable reconstructions of …


Assessing Integration In Resource And Environmental Management In The Southwest Yukon, Madison S. Saunders Jan 2007

Assessing Integration In Resource And Environmental Management In The Southwest Yukon, Madison S. Saunders

Theses and Dissertations (Comprehensive)

This thesis investigates the theory and practice of integration in resource and environmental management. Research on integration is growing as a result of the escalating demands placed on resources, an increase in the quality and quantity of information available concerning the environment, and the increased involvement and coordination of partners and participants in resource and environmental decision-making. Focus is placed on several resource and environmental decision-making. Focus is placed on several resources and environmental management processes in the Southwest Yukon, including wildlife management, protected areas management, forest management and environmental assessment. A case study approach is utilized to examine the …


Advanced Controller Design Using Neural Networks For Nonlinear Dynamic Systems With Application To Micro/Nano Robotics, Qinmin Yang Jan 2007

Advanced Controller Design Using Neural Networks For Nonlinear Dynamic Systems With Application To Micro/Nano Robotics, Qinmin Yang

Doctoral Dissertations

"The dissertation focuses on neural network (NN) control designs for nonlinear systems with application to micro/nano robotic. Critical problems in nano scale including thermal drift are also addressed"--Abstract, page iv.


Nonlinear Optimization Approach For Upfc Power Flow Control And Voltage Security: Sufficient System Constraints For Optimality, Radha P. Kalyani Jan 2007

Nonlinear Optimization Approach For Upfc Power Flow Control And Voltage Security: Sufficient System Constraints For Optimality, Radha P. Kalyani

Doctoral Dissertations

"This dissertation provides a nonlinear optimization algorithm for the long term control of Unified Power Flow Controller (UPFC) to remove overloads and voltage violations by optimized control of power flows and voltages in the power network. It provides a control strategy for finding the long term control settings of one or more UPFCs by considering all the possible settings and all the (N-1) topologies of a power network. Also, a simple evolutionary algorithm (EA) has been proposed for the placement of more than one UPFC in large power systems"--Abstract, page iv.


Harding University Catalog 2007-2008, Harding University Jan 2007

Harding University Catalog 2007-2008, Harding University

Harding Academic Catalogs

Academic catalog for the undergraduate programs at Harding University.


An Inside Look Behind Pandora.Com, Jackie Shane Jan 2007

An Inside Look Behind Pandora.Com, Jackie Shane

University Libraries & Learning Sciences Faculty and Staff Publications

No abstract provided.


A Simulation Environment Modeling The Use Of Wireless Sensor Networks For The Detection And Mapping Of Wildfires, Matthew Gann Jan 2007

A Simulation Environment Modeling The Use Of Wireless Sensor Networks For The Detection And Mapping Of Wildfires, Matthew Gann

Masters Theses

"Over the past 5 years, billions of dollars have been spent fighting wildfires which consume thousands of acres. Currently, satellites are the primary source of information regarding the location of large scale wildfires. The satellites in use are capable of reporting the location of the wildfire, but these reports are generated infrequently and have a low spatial resolution, where the reported location of the fire can be off by 500 meters. Timely detection (latency) and frequent report (throughput) are needed to help prevent the destruction caused by wildfires. This thesis, a system is described based on an ad-hoc wireless sensor …


Nonlinear Control Of Nonholonomic Mobile Robot Formations, Travis Alan Dierks Jan 2007

Nonlinear Control Of Nonholonomic Mobile Robot Formations, Travis Alan Dierks

Masters Theses

"In this thesis, the framework developed to control a single nonholonomic mobile robot is expanded to include the control of formations of multiple nonholonomic mobile robots. A combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers typically found in literature"--Abstract, page iv.


Vapor Phase Uptake Of Volatile Organic Contaminants By Hybrid Poplar Trees, Sally Rebecca Breite Jan 2007

Vapor Phase Uptake Of Volatile Organic Contaminants By Hybrid Poplar Trees, Sally Rebecca Breite

Masters Theses

"Phytoremediation, the use of plants to immobilize, degrade or remove contaminants from the environment, shows great promise as a remediation technique for many contaminated sites. Phytovolatilization in particular is of great interest for sites contaminated with chlorinated solvents and other volatile organic compounds (VOCs), many of which are recalcitrant to biodegradation. Hybrid poplar trees have been shown to uptake, translocate and volatilize numerous aqueous-phase VOCs, however vapor phase uptake of such compounds has only recently been observed and for only one contaminant, tetrachloroethylene (PCE). One semi-volatile and five volatile compounds were dosed to poplar trees in aqueous and vapor phase …


E-Design Tools For Friction Stir Welding: Cost Estimation Tool, Pradeep Kumar Tipaji Jan 2007

E-Design Tools For Friction Stir Welding: Cost Estimation Tool, Pradeep Kumar Tipaji

Masters Theses

"A cost model is an important tool for product design and material selection. An efficient and effective cost estimation tool is necessary for early design evaluation. In this paper, cost estimation models that estimate the production cost for Metal Inert Gas (MIG), Friction Stir (FS), and Friction Stir Spot (FSS) welded joints are presented. These models determine the cost incurred to fabricate each joint along with a detailed explanation of each cost component. Each cost component has been closely analyzed and major cost components have been included in the cost model"--Abstract, page iv.


Toward Improving Performance Measurement In Public Sector Organizations, Matthew Thomas Kutz Jan 2007

Toward Improving Performance Measurement In Public Sector Organizations, Matthew Thomas Kutz

Masters Theses

"The objective of this research is to investigate various means of improving the performance measurement methods for public sector organizations. A case study is conducted using data from the Missouri Department of Transportation (MoDOT). As a government organization, MoDOT must publish measurements of its performance for the general public and for the legislators who provide funding. Currently, MoDOT produces a quarterly publication, called the Tracker, for performance measurement reporting. This research hypothesizes that the Tracker is not an effective performance measurement system and stakeholders of MoDOT would benefit from a more concise and pointed report of MoDOT performance. A software …


Manufacturing Of High Performance Composites Using Vacuum Assisted Resin Transfer Molding, V. G. K. Menta Jan 2007

Manufacturing Of High Performance Composites Using Vacuum Assisted Resin Transfer Molding, V. G. K. Menta

Masters Theses

"The objective of this research is to establish and enhance the existing Vacuum Assisted Resin Transfer Molding (VARTM) process to manufacture high performance composite parts usable in the aerospace industry.

Flat, hat, pi and multi stiffened panels have been manufactured by the VARTM process using AS4-5HS and AS4-8HS carbon fabric, and SI-ZG-5A low viscosity epoxy resin. Silicone-based reusable molds have been designed and developed to manufacture stiffened panels. Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) experiments of the SI-ZG-5A resin system were conducted to determine the storage modulus, loss modulus, and the glass transition temperature. The density and …


Colour Doppler Spatial Resolution Performance Testing, Jacinta Browne, Ian Brown, Peter Hoskins, Amanda Watson, Alex Elliott Jan 2007

Colour Doppler Spatial Resolution Performance Testing, Jacinta Browne, Ian Brown, Peter Hoskins, Amanda Watson, Alex Elliott

Articles

No abstract available


Matrix Effects, Development Of Clean-Up And Lc-Techniques Contributing Towards A Reference Lcms Method For The Analysis Of Lipophilic Marine Toxins, Mairead Anne Mcelhinney Jan 2007

Matrix Effects, Development Of Clean-Up And Lc-Techniques Contributing Towards A Reference Lcms Method For The Analysis Of Lipophilic Marine Toxins, Mairead Anne Mcelhinney

Masters

The most widely used reference method in Europe for the detection and monitoring of lipophilic marine toxins is the Mouse Bioassay (MBA) as first described by Yasumoto et al., (1978). The MBA offers a good level of protection to human health and is capable of detecting the overall toxicity of previously known toxins. However, there are drawbacks associated with the use of the MBA as it is both expensive and time consuming and can give false positives due to interferences (Suzuki et al, 1976). The problems associated with the original mouse bioassay have led to several modifications (Yasumoto et al, …


Common Data Set, 2006-2007, Planning, Research, And Policy Analysis Jan 2007

Common Data Set, 2006-2007, Planning, Research, And Policy Analysis

Common Data Set (2001-present)

Common Data Set 2006-2007 for Illinois State University


The Pioneer, Vol. 12, No. 1, Winter 2007, Illinois State University, College Of Education Jan 2007

The Pioneer, Vol. 12, No. 1, Winter 2007, Illinois State University, College Of Education

The Pioneer (alumni newsletter)

Alumni Newsletter for University High School, College of Education


The Trademark Jurisprudence Of Judge Rich, Jeffrey M. Samuels, Linda B. Samuels Jan 2007

The Trademark Jurisprudence Of Judge Rich, Jeffrey M. Samuels, Linda B. Samuels

American University Law Review

For nearly forty-three years, Giles Sutherland Rich served as a member of the U.S. Court of Customs and Patent Appeals (C.C.P.A.) and its successor court, the U.S. Court of Appeals for the Federal Circuit. Judge Rich is widely regarded as one of the most influential jurists in the area of patent law—and rightfully so. Less well known is that Judge Rich also authored many significant decisions in the area of trademark law. Judge Rich’s opinions in the area of trademarks span the spectrum of trademark registrability issues and explore important issues of public policy. This Article reviews a number of …


Reinforcement Learning Neural-Network-Based Controller For Nonlinear Discrete-Time Systems With Input Constraints, Pingan He, Jagannathan Sarangapani Jan 2007

Reinforcement Learning Neural-Network-Based Controller For Nonlinear Discrete-Time Systems With Input Constraints, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel adaptive-critic-based neural network (NN) controller in discrete time is designed to deliver a desired tracking performance for a class of nonlinear systems in the presence of actuator constraints. The constraints of the actuator are treated in the controller design as the saturation nonlinearity. The adaptive critic NN controller architecture based on state feedback includes two NNs: the critic NN is used to approximate the "strategic" utility function, whereas the action NN is employed to minimize both the strategic utility function and the unknown nonlinear dynamic estimation errors. The critic and action NN weight updates are derived by minimizing …