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Polarographic Studies On The Kinetics Of The Electrode Reaction Of 4-Benzoyl-1,5 Diphenyl Pyrazole-3-Carboxylic Acid, M. Veri̇rşen, S. Erturan Jan 1998

Polarographic Studies On The Kinetics Of The Electrode Reaction Of 4-Benzoyl-1,5 Diphenyl Pyrazole-3-Carboxylic Acid, M. Veri̇rşen, S. Erturan

Turkish Journal of Chemistry

The polarographic behavior of 4-Benzoyl-1,5 diphenyl pyrazole-3- Carboxylic acid (BDPPCA) in aqueous ethanol solution (76 \% v/v) at 25^oC was studied as a function of pH using Mcl buffer solution. One well-defined wave was obtained in the pH range of 3.3-5.4. This wave, corresponding to two electron reduction processes, was irreversible and diffusion controlled. However, in the pH range of 5.4-7.4 a single reversible and diffusion-controlled wave involving two electrons resulted. The kinetic parameters $(n_a, k^o_{f,h})$ were calculated by Koutecky's method. A tentative mechanism was put forward for the reduction process of depolarizer. Furthermore, the effects of different supporting electrolytes …


Separation Of Molybdenum, Vanadium And Nickel By Liquid-Liquid Extraction, T. Coşar, R. Zi̇yadanoğullari Jan 1998

Separation Of Molybdenum, Vanadium And Nickel By Liquid-Liquid Extraction, T. Coşar, R. Zi̇yadanoğullari

Turkish Journal of Chemistry

Elements in the ash of asphaltites that is used in thermal central for power generation units are Mo, V, U, Ti and Ni. The main goal of this study was to separate molybdenum, vanadium and nickel from the aqueous solution. The quantities of the above elements in solution were in the range of 50-80 ppm. The separate these elements from solution, the liquid-liquid extraction method was applied to samples. Alamine 336 was used as extractant. During the reduction-oxidation processes, single and multiple extraction methods were applied to the solution in combination. The quantities of molybdenum, vanadium and nickel in the …


Potentiometric Investigation Of The Effects Of Several Substituents On The Basicity Of Benzilidene-O-Hydroxyaniline, Esma Kiliç, Orhan Atakol, E. Canel, Zehra Ali̇beşeoğlu, Turgut Gündüz, Fitnat Köseoğlu Jan 1998

Potentiometric Investigation Of The Effects Of Several Substituents On The Basicity Of Benzilidene-O-Hydroxyaniline, Esma Kiliç, Orhan Atakol, E. Canel, Zehra Ali̇beşeoğlu, Turgut Gündüz, Fitnat Köseoğlu

Turkish Journal of Chemistry

Chloro-, bromo-, iodo-, nitro-, methoxy- and hydroxy-substituted benzilidene-o-hydroxyaniline were prepared in order to investigate the effects of substituents on the basicity of benzilidene-o-hydroxyaniline. For each substituent, three isomers -- ortho, meta and para -- were synthesised. Schiff bases were titrated potentiometrically with perchloric acid in nitrobenzene solvent at $25^{\circ}$C. All compounds gave well-shaped titration curves, from which half-neutralisation potentials were calculated. The trend in the values of half-neutralisation potentials of Schiff bases were explained in terms of the nature of the substituents. The applicability of the Hammett equation to the effect of substituents in Schiff bases in nitrobenzene solvent was …


Winchell Posters Jan 1998

Winchell Posters

Journal of the Minnesota Academy of Science

Abstracts from the Winchell Posters given at the 66th Annual Meeting for the Journal of the Minnesota Academy of Science.


Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence Jan 1998

Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence

Faculty Publications

The rigors of employment-directed undergraduate education. and decreased emphasis on "Liberal Arts" studies occurring at some colleges and universities has left many graduates with a level of scientific understanding which is inadequate to make infonned choices about issues which effect the environment. To address this lack of scientific understanding. the Chesapeake Bay National Estuarine Research Reserve (Virginia) and the Virginia Institute of Marine Science, with the Marshall-Wythe School of Law and the School of Business Administration of the College of William and Mary are developing a Coastal Ecosystem Science Program to teach future law and business professionals the basics of …


Gravity Drainage Prior To Cake Filtration, Scott A. Wells, Gregory K. Savage Jan 1998

Gravity Drainage Prior To Cake Filtration, Scott A. Wells, Gregory K. Savage

Civil and Environmental Engineering Faculty Publications and Presentations

During the initial stages of a Buchner funnel or specific resistance test, gravity drainage occurs prior to application of the pressure differential. Some allow time for a small cake to form by gravity drainage. Filtrate data from the gravity drainage period can be used to determine constitutive properties of the cake under a hydrostatic pressure gradient. The constitutive properties that define the structure of the cake include the permeability and porosity as functions of the applied stress. Equations governing the drainage rate during a gravity filtration experiment assuming a constant and a non-constant average cake permeability and cake porosity were …


Strictly Level-Decreasing Logic Programs, Pascal Hitzler, Anthony K. Seda Jan 1998

Strictly Level-Decreasing Logic Programs, Pascal Hitzler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

We study strictly level-decreasing logic programs (sld-programs) as defined earlier by the present authors. It will be seen that sld-programs, unlike most other classes of logic programs, have both a highly intuitive declarative semantics, given as a unique supported model, and are computationally adequate in the sense that every partial recursive function can be represented by some sld-program P. Allowing for a safe use of cuts, an interpreter based on SLDNF-resolution, as implemented for example in standard Prolog systems, is shown to be sound and complete with respect to this class of programs. Furthermore, we study connections between topological …


Interestingness Of Discovered Association Rules In Terms Of Neighborhood-Based Unexpectedness, Guozhu Dong, Jinyan Li Jan 1998

Interestingness Of Discovered Association Rules In Terms Of Neighborhood-Based Unexpectedness, Guozhu Dong, Jinyan Li

Kno.e.sis Publications

One of the central problems in knowledge discovery is the development of good measures of interestingness of discovered patterns. With such measures, a user needs to manually examine only the more interesting rules, instead of each of a large number of mined rules. Previous proposals of such measures include rule templates, minimal rule cover, actionability, and unexpectedness in the statistical sense or against user beliefs.

In this paper we will introduce neighborhood-based interestingness by considering unexpectedness in terms of neighborhood-based parameters. We first present some novel notions of distance between rules and of neighborhood of rules. The neighborhood-based interestingness of …


Determining Capture Zones For Three-Dimensional, Heterogeneous, Anisotropic Aquifers By Monte Carlo Analysis, Jon Paul Jones Jan 1998

Determining Capture Zones For Three-Dimensional, Heterogeneous, Anisotropic Aquifers By Monte Carlo Analysis, Jon Paul Jones

Theses and Dissertations

Most methods of delineating capture zones for pump-and-treat remedial design and wellhead protection assume a two-dimensional, homogeneous aquifer. Aquifers, however, are three-dimensional and heterogeneous, thereby introducing uncertainty in capture zone analysis. This study used a Monte Carlo analysis of three sets of statistical parameters defining aquifer heterogeneity. Each set had a different variance for the mean natural log hydraulic conductivity, which varied among the sets by a factor of four. The ensemble means of the capture zones for each set were estimated from 10 randomly generated fields with 12 layers each which were superimposed on each other for a total …


Overview Of The 8th International Symposium On Vulcanospeleology, William R. Halliday Jan 1998

Overview Of The 8th International Symposium On Vulcanospeleology, William R. Halliday

International Journal of Speleology

In February 1998 the 8h International Symposium on Vulcanospeleology was hosted by CEGEA (Cave Exploration Group of East Africa) in Nairobi, Kenya: it was attended by 16 scientists coming from 4 continents. Pre- and Post- Symposium excursions allowed the participants to have an overview on the most important and famous volcanic cave of that area.


Mechanistic Studies Of Cation Photogeneration, Mary Frances Clifton Jan 1998

Mechanistic Studies Of Cation Photogeneration, Mary Frances Clifton

Dissertations

No abstract provided.


The Auditory Display In Interactive Courseware: Moving Human Factors Into Computer Education, David T. Lauret Jan 1998

The Auditory Display In Interactive Courseware: Moving Human Factors Into Computer Education, David T. Lauret

CCAC Theses and Dissertations

The arrival of inexpensive high fidelity audio capabilities for personal computers has been accompanied by sweeping claims of enhanced educational effectiveness. Research has only served to confuse these claims with both significant and non-significant findings. This may be due partly to the single dimensional model which has been assumed when examining audio. When computer-based audio is examined as a multi-dimensional display analogous in capability and function to the more familiar visual display (computer screen), a different picture emerges. Although it is now clear that integrated audio can enhance learning, the instructional designer is still left with little guidance whether or …


High-Power Diffusion Cooling Planar Waveguide Co_{2} Laser, E. Taal, M. S. Kiliçkaya Jan 1998

High-Power Diffusion Cooling Planar Waveguide Co_{2} Laser, E. Taal, M. S. Kiliçkaya

Turkish Journal of Physics

A diffusion-cooled CO_{2} laser using a coaxial waveguide is investigated theoretically. The resonator extracting the laser beam consits of two annular plane mirrors enclosing the two ends of the waveguide. A theoretical resonator model based on the vector modes of propagation in a dielectric coaxial waveguide is described.


Using Multimedia Microworlds To Motivate And Engage Adult Learners, Susan B. Stoney Jan 1998

Using Multimedia Microworlds To Motivate And Engage Adult Learners, Susan B. Stoney

Theses: Doctorates and Masters

As educational institutions come under increasing pressure from outside forces to restructure the way students learn, efforts are being made by researchers to find ways to assist students to learn through independent thought and to solve problems in a resource-based, self-paced environment. Such an environment needs to be sufficiently interesting and novel to motivate students who begin to use it, and to continue to engage them as they progress through it. This study has sought to identify what such a learning environment needs to encompass in order to motivate and engage adult learners so that they will not only want …


Performing Cooperative Work And Conferencing On An Intranet Using Java, Thaveeporn Limpanyalers Jan 1998

Performing Cooperative Work And Conferencing On An Intranet Using Java, Thaveeporn Limpanyalers

Theses: Doctorates and Masters

The process of organising, preparing and conducting a meeting is a time consuming one. Additionally, geographic separation compounds the amount of effort required. Within this study, an electronic conferencing system in an Intranet environment is designed and implemented, thus enabling employees in the same organisation to meet up electronically without the dual constraints of time and space. Specifically, the study investigates incorporation of facial expressions and an ongoing polling system. The results demonstrate that a presence of facial expressions helps users to better engage in on-line discussion and that users find an ongoing poll to be useful in determining direction …


Adaptive Prefetching For Device-Independent File I/O, Dan Revel, Dylan Mcnamee, David Steere, Jonathan Walpole Jan 1998

Adaptive Prefetching For Device-Independent File I/O, Dan Revel, Dylan Mcnamee, David Steere, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Device independent I/O has been a holy grail to operating system designers since the early days of UNIX. Unfortunately, existing operating systems fall short of this goal for multimedia applications. Techniques such as caching and sequential read-ahead can help mask I/O latency in some cases, but in others they increase latency and add substantial jitter. Multimedia applications, such as video players, are sensitive to vagaries in performance since I/O latency and jitter affect the quality of presentation. Our solution uses adaptive prefetching to reduce both latency and jitter. Applications submit file access plans to the prefetcher, which then generates I/O …


Dissociation Constants Of Oxalic Acid In Aqueous Sodium Chloride And Sodium Trifluoromethanesulfonate Media To 175 °C, Richard Kettler, David J. Wesolowski, Donald A. Palmer Jan 1998

Dissociation Constants Of Oxalic Acid In Aqueous Sodium Chloride And Sodium Trifluoromethanesulfonate Media To 175 °C, Richard Kettler, David J. Wesolowski, Donald A. Palmer

Department of Earth and Atmospheric Sciences: Faculty Publications

The first and second molal dissociation constants of oxalic acid were measured potentiometrically in a concentration cell fitted with hydrogen electrodes. Measurements were made at six temperatures ranging from 5 °C to 125 °C at four ionic strengths ranging from 0.1 mol•kg-1 to 1.0 mol•kg-1 (NaCl and NaCF3-SO3). The second molal dissociation constant was measured in NaCF3SO3 media only. The data obtained in this study were combined with the corresponding literature values, including a number of recalculated Harned cell and concentration cell measurements and previous results from this laboratory. Data for …


Signal Injection With Perceptual Criteria, T. Engi̇n Tuncer Jan 1998

Signal Injection With Perceptual Criteria, T. Engi̇n Tuncer

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel method for increasing the coding performance and information transmission capacity is presented. This method is mainly based on perceptual modelling of input signal such as speech or audio. Presented approach may be seen as an alternative to transforms which dynamically change analysis window for better energy compaction. A perceptual model is established in order to obtain a global masking threshold in frequency below which sounds become inaudible. Certain criteria are developed for identifying the signal injection bands. A new multiband filter design method which is a generalization of windowing method is used to separate the …


Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell Jan 1998

Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell

Bulletins 4000 -

This Bulletin was developed by Department of Agriculture in recognition of the increasing complexity and competitiveness in establishing a commercial vegetable enterprise. The information in this Bulletin will provide you with a useful guide to assess your likelihood of succeeding in vegetable production.

Vegetable production is not an easy lifestyle. It is a highly competitive environment with the industry consisting of growers with big investments and years of experience and knowledge. Horticultural farms require a large amount of capital and time and are increasingly expanding and becoming more specialised.

If you are serious about growing vegetables, work through this Bulletin …


The Hermite Cubic Collocation Approximation To The Eigenvalues And The Eigenfuntions Of The Laplace Operator, Wayne R. Dyksen Jan 1998

The Hermite Cubic Collocation Approximation To The Eigenvalues And The Eigenfuntions Of The Laplace Operator, Wayne R. Dyksen

Department of Computer Science Technical Reports

No abstract provided.


Percentile Blobs For Image Similarity, Nicholas Howe Jan 1998

Percentile Blobs For Image Similarity, Nicholas Howe

Computer Science: Faculty Publications

We present a new algorithm called PBSIM for computing image similarity, based upon a novel method of extracting bloblike features from images. In tests on a classification task using a data set of over 1000 images, PBSIM shows significantly higher accuracy than algorithms based upon color histograms, as well as previously reported results for another approach based upon bloblike features.


Methods Of Preparing Three-Dimensional, Macroscopic Assemblages Of Carbon Fibrils And The Products Obtained Thereby, Hyperion Catalysis International, Inc., Howard Tennent, Robert W. Hausslein, Nicholas Leventis, David Moy Jan 1998

Methods Of Preparing Three-Dimensional, Macroscopic Assemblages Of Carbon Fibrils And The Products Obtained Thereby, Hyperion Catalysis International, Inc., Howard Tennent, Robert W. Hausslein, Nicholas Leventis, David Moy

Chemistry Faculty Research & Creative Works

A method of making randomly oriented carbons fibrils having a cylindrical constant diameter with c-axes perpendicular to their cylindrical axis, which are free of pyrolytically deposited carbon, with a diameter of between 3.5 and 70 nanometers, by dispersing carbon fibrils in a medium and separating them from the medium, by filtration or evaporation to form a porous mat or sheet.


A New Method Of Retrieving Surface Bidirectional Reflectance From Ground Measurements: Atmospheric Sensitivity Study, A. I. Lyapustin, J. L. Privette Jan 1998

A New Method Of Retrieving Surface Bidirectional Reflectance From Ground Measurements: Atmospheric Sensitivity Study, A. I. Lyapustin, J. L. Privette

United States National Aeronautics and Space Administration: Publications

Commonly, experimental data on surface directional reflectance are not properly corrected for atmospheric effects. In this paper, we describe a new method for rigorous retrieval of the bidirectional reflectance distribution function (BRDF) from ground-based measurements.


College Of San Mateo Mathematics And Science Teacher Education Program: A Bay Area Collaborative For Excellence In Teacher Preparation With San Jose State University And San Francisco State University, C. Tonini Jan 1998

College Of San Mateo Mathematics And Science Teacher Education Program: A Bay Area Collaborative For Excellence In Teacher Preparation With San Jose State University And San Francisco State University, C. Tonini

Journal of Mathematics and Science: Collaborative Explorations

The College of San Mateo (CSM), a community college serving the San Mateo County area of California, is part of a collaborative effort in the San Francisco Bay Area to improve mathematics and science teacher preparation. With funding mainly through the National Science Foundation, the project is locally referred to as the MASTEP Project (Math and Science Teacher Education Program). MASTEP partners include two California State Universities (San Jose State University and San Francisco State University), four community colleges (College of San Mateo, City College of San Francisco, Evergreen Valley Community College, and San Jose City College), selected K-12 schools, …


The Community College Of Philadelphia: Educating Teachers For A Changing World, K. Armstrong Jan 1998

The Community College Of Philadelphia: Educating Teachers For A Changing World, K. Armstrong

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Aegis Data Analysis And Reduction (Adar) In Support Of The Aegis Weapon System (Aws), June Bullard Gaines Jan 1998

Aegis Data Analysis And Reduction (Adar) In Support Of The Aegis Weapon System (Aws), June Bullard Gaines

Theses and Dissertations

The AEGIS Weapons System (AWS), part of the AEGIS Combat System (ACS), is an integral part of the defense system on U.S. Navy AEGIS-class ships. AEGIS Data Analysis and Reduction (ADAR) has been developed to assist in the evaluation of the AWS data. ADAR, along with the AWS and ACS, has evolved through the years to accommodate advances in technology and computer programming languages. Additionally, ADAR has evolved so that users located at sites other than the Naval Surface Warfare System Dahlgren Division (NSWCDD), Dahlgren, Virginia, can reduce tactical system data and perform data analysis using the reduced data.

This …


Imaging Tissue Conductivity Via Contactless Measurements: A Feasibility Study, Nevzat G. Gençer, M. Nejat Tek Jan 1998

Imaging Tissue Conductivity Via Contactless Measurements: A Feasibility Study, Nevzat G. Gençer, M. Nejat Tek

Turkish Journal of Electrical Engineering and Computer Sciences

The feasibility of a new imaging system is investigated. This system will be used to image electrical conductivity distribution of biological tissues via contactless measurements. This will be achieved by introducing currents in the conductive medium using time-varying magnetic fields and measuring the magnetic fields of the induced currents. Consequently, the imaging system consists of transmitter and receiver coils placed nearby the conductive body. In this study, the basic features of the coplanar and coaxial coils are studied. The validity of the simplifying assumptions for the governing field equations is investigated. It is found that, for operating frequency of 100 …


Data Mining In Electronic Media Usage Statistics: A Case Study Of Knowledge Discovery In Databases, Peter J. Lindquist Jan 1998

Data Mining In Electronic Media Usage Statistics: A Case Study Of Knowledge Discovery In Databases, Peter J. Lindquist

Honors Theses, 1963-2015

As databases grow larger, analysts are turning to computers to help them analyze the massive amounts of data their computers have collected. As the difference between having data and having useful information becomes more clear, different methods of using computers to analyze data are becoming available. Knowledge Discovery in Databases (KDD) is a general methodology for preparing the data, using software algorithms to discover new patterns or relationships in the data, and integrating the results back into the system. The KDD methodology is explained and hypothetically applied to usage statistics generated by the CSB/SJU Libraries Internet resources. Examples are drawn …


Biomineralization Of Magnetic Iron Minerals In Bacteria, Richard B. Frankel, Dennis A. Bazylinski, Dirk Schϋler Jan 1998

Biomineralization Of Magnetic Iron Minerals In Bacteria, Richard B. Frankel, Dennis A. Bazylinski, Dirk Schϋler

Physics

Magnetotactic bacteria orient and migrate along magnetic field lines. This ability is based on a submicron assembly of single-magnetic domain iron mineral particles that elegantly solves the problem of how to construct a magnetic dipole that is large enough to be oriented in the geomagnetic field at ambient temperature, yet fit inside a micron-sized cell. The solution is based on the ability of the bacteria to accumulate high concentrations of iron, and control the deposition, size and orientation of a specific iron mineral at specific locations in the cell.


Ion Bernstein Waves Driven By Two Transverse Flow Layers, Mark Anthony Reynolds, G. Ganguli Jan 1998

Ion Bernstein Waves Driven By Two Transverse Flow Layers, Mark Anthony Reynolds, G. Ganguli

Publications

The interaction between two narrow layers of E3B flow is investigated, along with their stability properties. The mode frequencies, growth rates, and eigenfunctions are calculated. It is found that the instability due to a single layer is robust to the inclusion of a second layer. Specifically, when the separation between the layers is on the order of the ion-cyclotron radius, there is strong coupling between the two layers and the second layer is destabilizing. In addition, when the flow velocities are in opposite directions a wide variety of modes is possible, including near-zero-frequency modes, resulting in broadband structure in both …