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The Electro-Catalytic Oxidation Of Hcooh On Electrodeposited Pd Electrode, Quan Zhou, Cun-Zhong Zhang, Xiao-Lin Lu, Zhong-Da Wu Aug 2000

The Electro-Catalytic Oxidation Of Hcooh On Electrodeposited Pd Electrode, Quan Zhou, Cun-Zhong Zhang, Xiao-Lin Lu, Zhong-Da Wu

Journal of Electrochemistry

The coherent electroplates were prepared by electro depositing Pd on supporting materials glassy carbon. The surface morphology of the electrodes was examined by SEM. The electro oxidation of HCOOH in HClO4 solution was investigated by using cyclic voltammetry. The results show that the deposited conditions in the preparation of electrodes by electro depositing Pd affect the electrodes electro catalytic activity to the oxidation of HCOOH. The platinized Pd electrode on GC substrates using large current density is of higher catalytic activity to the oxidation of HCOOH than Pd electrode. The electro catalytic activity of PdO formed on the Pd …


Fermentation Strategies For Recombinant Protein Expression In The Methylotrophic Yeast Pichia Pastoris, Wenhui Zhang, Mehmet Inan, Michael M. Meagher Aug 2000

Fermentation Strategies For Recombinant Protein Expression In The Methylotrophic Yeast Pichia Pastoris, Wenhui Zhang, Mehmet Inan, Michael M. Meagher

Papers in Biochemical Engineering

Fermentation strategies for recombinant protein production in Pichia pastoris have been investigated and are reviewed here. Characteristics of the expression system, such as phenotypes and carbon utilization, are summarized. Recently reported results such as growth model establishment, application of a methanol sensor, optimization of substrate feeding strategy, DOstat controller design, mixed feed technology, and perfusion and continuous culture are discussed in detail.


An Analysis Of The Influence Of Age And Ionizing Radiation On Cognitive Performance, Elizabeth L. Gerhardt Aug 2000

An Analysis Of The Influence Of Age And Ionizing Radiation On Cognitive Performance, Elizabeth L. Gerhardt

Master's Theses - Daytona Beach

This thesis was designed to study whether age has a significant effect on cognitive test results among persons exposed to ionizing radiation. The data for this investigation came from the fourth year of a 1995-98 longitudinal study of subjects exposed to radiation from the 1986 Chernobyl, Ukraine, nuclear power plant accident. Accuracy and efficiency scores from four cognitive tests taken by 84 Ukrainian volunteers were divided into two age groups and three radiation dosage groups for analysis. The results of this study found that decrements in human performance on tasks involving spatial processing increase with age in persons who have …


Santa Clara Magazine, Volume 42 Number 1, Summer 2000, Santa Clara University Jul 2000

Santa Clara Magazine, Volume 42 Number 1, Summer 2000, Santa Clara University

Santa Clara Magazine

8 - ATTACK OF THE KILLER TOMATOES? By Miriam Schulman. Beyond the hype of the headlines, there are no simple answers to the ethical questions raised by genetically modified food.

14 - BRAVE NEW WORLD By Tamara Straus. Now the lawyers want inside your head as they struggle to answer, "Who owns an idea?" Just the mere question is changing the face of legal education.

18 - THE GREAT GRADE GIVEAWAY By Jeff Zorn. Today's grades don't mean jack. So says one Santa Clara professor in this memoir and commentary on the evils of modern day grade inflation.

22 - …


Fluid Flow In Micro-Channels: A Stochastic Approach, Hilda Marino Black Jul 2000

Fluid Flow In Micro-Channels: A Stochastic Approach, Hilda Marino Black

Doctoral Dissertations

In this study free molecular flow in a micro-channel was modeled using a stochastic approach, namely the Kolmogorov forward equation in three dimensions. Model equations were discretized using Central Difference and Backward Difference methods and solved using the Jacobi method. Parameters were used that reflect the characteristic geometry of experimental work performed at the Louisiana Tech University Institute for Micromanufacturing.

The solution to the model equations provided the probability density function of the distance traveled by a particle in the micro-channel. From this distribution we obtained the distribution of the residence time of a particle in the micro-channel. Knowledge of …


An Investigation Of Skill Acquisition Under Conditions Of Augmented Reality, Russell P. Milham Jul 2000

An Investigation Of Skill Acquisition Under Conditions Of Augmented Reality, Russell P. Milham

Master's Theses - Daytona Beach

Augmented reality is a virtual environment that integrates rendered content with the experience of the real world. There is evidence suggesting that augmented reality provides for important spatial constancy of objects relative to the real world coordinate system and that this quality contributes to rapid skill acquisition. The qualities of simulation, through the use of augmented reality, may be incorporated into actual job activities to produce a condition of "just-in-time learning." This may make possible the rapid acquisition of information and reliable completion of novel or infrequently performed tasks by individuals possessing a basic skill-set. The purpose of this research …


Validation Of Passive Air Sampling Monitors Onboard United States Navy Submarines, Larry A. Mcfarland Jul 2000

Validation Of Passive Air Sampling Monitors Onboard United States Navy Submarines, Larry A. Mcfarland

Community & Environmental Health Theses & Dissertations

An operating submarine creates a unique air quality mixture of compounds that result from a combination of human metabolism, construction materials, materials brought onboard and compounds created through the interaction of ship systems. A comprehensive study of submarine atmospheres is ongoing during deployments of U.S. Navy nuclear submarines. As part of the overall effort, a paired air sampling comparison field validation was conducted to compare the air sampling effectiveness of passive diffusive monitors compared to more traditional active air sampling methods when sampling for acrolein, formaldehyde and ozone in the enclosed submarine atmosphere. Acrolein monitors containing 2-hydroxymethylpiperidine (HMP) impregnated glass …


Effects Of Solvent Mixtures On Dispersion Of Lanthanum-Modified Lead Zirconate Titanate Tape Casting Slurries, Jian-Huei Feng, Fatih Dogan Jul 2000

Effects Of Solvent Mixtures On Dispersion Of Lanthanum-Modified Lead Zirconate Titanate Tape Casting Slurries, Jian-Huei Feng, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The effects of xylenes/ethanol solvent mixtures on lanthanum-modified lead zirconate titanate (PLZT) nonaqueous suspensions were investigated by measuring sediment height, viscosity, and adsorption of dispersant. Well-dispersed colloidal suspensions were obtained in xylene-rich solvents with a minimum amount of menhaden fish oil as a dispersant. It was also shown that adsorption of dispersant on particle surfaces strongly depends on selection of solvent(s). The ratio of solvent mixture affects PLZT solids content of unfired tapes, in which using insufficient as well as excess dispersant could decrease the packing density of particles. Solubility of other organic additives, such as binder, was also considered …


Advanced Atmospheric Water Vapor Dial Detection System, Tamer Refaat Jul 2000

Advanced Atmospheric Water Vapor Dial Detection System, Tamer Refaat

Electrical & Computer Engineering Theses & Dissertations

Measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a powerful method to perform such measurement from aircraft and space. This thesis describes a new advanced detection system, which incorporates major improvements regarding sensitivity and size. These improvements include a low noise advanced avalanche photodiode detector, a custom analog circuit, a 14-bit digitizer, a microcontroller for on board averaging and finally a fast computer interface.

This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto …


Effectiveness Of A Multimedia General Education Course, Patricia Backer Jun 2000

Effectiveness Of A Multimedia General Education Course, Patricia Backer

Faculty Publications

The current paper describes the design, development, and evaluation of self-paced multimedia modules that are used in an advanced General Education course at San Jose State University. The design and development cycle of these modules began in 1994 and continues to this date. The General Education course, Technology and Civilization (TECH 198), is designed to introduce students to the realm of history and usage of technology in society and to increase their awareness of both the uncertainties as well as the promises of the utilization of technology as a creative human enterprise. During the summer session 1999, the completed modules …


Psychopolitical Dynamics Of Air Rage, Ibpp Editor Jun 2000

Psychopolitical Dynamics Of Air Rage, Ibpp Editor

International Bulletin of Political Psychology

This article describes two elements of the psychopolitical dynamics of air rage. The first comprises the rise of air rage as a labeling construct. The second comprises aspects of perceived power and social perception that seem to engender behavior labeled as air rage.


Statistical Continuum Theory For Large Plastic Deformation Of Polycrystalline Materials, Brent L. Adams, S. Ahzi, H. Garmestani, S. Lin Jun 2000

Statistical Continuum Theory For Large Plastic Deformation Of Polycrystalline Materials, Brent L. Adams, S. Ahzi, H. Garmestani, S. Lin

Faculty Publications

This paper focuses on the application of statistical continuum mechanics to the prediction of mechanical response of polycrystalline materials and microstructure evolution under large plastic deformations. A statistical continuum mechanics formulation is developed by applying a Green's function solution to the equations of stress equilibrium in an infinite domain. The distribution and morphology of grains (crystals) in polycrystalline materials is represented by a set of correlation functions that are described by the corresponding probability functions. The elastic deformation is neglected and a viscoplastic power law is employed for crystallographic slip in single crystals. In this formulation, two- and three-point probability …


Rate-Distortion Adaptive Vector Quantization For Wavelet Imagecoding, Qun Gu, Scott E. Budge Jun 2000

Rate-Distortion Adaptive Vector Quantization For Wavelet Imagecoding, Qun Gu, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

We propose a wavelet image coding scheme using rate-distortion adaptive tree-structured residual vector quantization. Wavelet transform coefficient coding is based on the pyramid hierarchy (zero-tree), but rather than determining the zero-tree relation from the coarsest subband to the finest by hard thresholding, the prediction in our scheme is achieved by rate-distortion optimization with adaptive vector quantization on the wavelet coefficients from the finest subband to the coarsest. The proposed method involves only integer operations and can be implemented with very low computational complexity. The preliminary experiments have shown some encouraging results: a PSNR of 30.93 dB is obtained at 0.174 …


Gaussian Beams In Hollow Metal Waveguides, Lee W. Casperson Jun 2000

Gaussian Beams In Hollow Metal Waveguides, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Various families of Gaussian beams have been explored previously to represent the propagation of nearly plane electromagnetic waves in media having at most quadratic transverse variations of the index of refraction and the gain or loss in the vicinity of the beam. However, such beams cannot directly represent the wave solutions for propagation in planar or rectangular waveguides, and sinusoidal mode functions are more commonly used for such waveguides. On the other hand, it is also useful to consider the possibility of recurring Gaussian beams that have an approximately Gaussian transverse profile at certain distinct planes along the propagation path. …


Endotoxin Removal From Protein Solutions By Immobilized Metal Ion Affinity Chromatography, Yun Kang May 2000

Endotoxin Removal From Protein Solutions By Immobilized Metal Ion Affinity Chromatography, Yun Kang

Dissertations

In the biotechnology/pharmaceutical industry, the removal of endotoxins from final protein product has always been a challenge. A novel method for endotoxin removal from protein solutions, immobilized metal (ion) affinity chromatography (IMAC) has been developed in this study. Fe3+ was charged to a chelating gel that contains iminodiacetic acid (IDA). The IDA- Fe3+ IMAC column was exploited to remove endotoxin from protein solutions. This method involves the adsorption of the endotoxin on IMAC column. More than 99% endotoxin is removed and protein yield is higher than 90%. IDA-Fe3+ IMAC has proved to be an economical and efficient …


Video Traffic Modeling And Delivery, Hai Liu May 2000

Video Traffic Modeling And Delivery, Hai Liu

Dissertations

Video is becoming a major component of the network traffic, and thus there has been a great interest to model video traffic. It is known that video traffic possesses short range dependence (SRD) and long range dependence (LRD) properties, which can drastically affect network performance. By decomposing a video sequence into three parts, according to its motion activity, Markov-modulated self-similar process model is first proposed to capture autocorrelation function (ACF) characteristics of MPEG video traffic. Furthermore, generalized Beta distribution is proposed to model the probability density functions (PDFs) of MPEG video traffic.

It is observed that the ACF of MPEG …


Fluidization And Soot Filtration In A Rotating Fluidized Bed, Gui-Hua Qian May 2000

Fluidization And Soot Filtration In A Rotating Fluidized Bed, Gui-Hua Qian

Dissertations

A horizontal rotating fluidized bed (RFB) has been investigated for the removal of soot from diesel engine exhaust. This requires necessitating an understanding of the nature of fluidization, particle mixing and filtration in the RFB.

In an RFB, particles are subject to a centrifugal force which can be much larger than the force of gravity. Therefore the Geldart classification for conventional fluidized beds must be modified for rotating fluidized beds. A theoretical analysis shows that group A particles (minimum bubbling velocity Umb > minimum fluidization velocity Umf can shift to group B Umb = Umf and group …


An Integrated Membrane-Based Chromatographic Process For Biomolecule Isolation And Purification, Xiaoping Dai May 2000

An Integrated Membrane-Based Chromatographic Process For Biomolecule Isolation And Purification, Xiaoping Dai

Dissertations

Biomolecules obtained from fermentation and cell-culture processes are present in low concentrations in a complex medium/broth. For intracellular products, cells are first harvested. Subsequently, cell lysis and homogenization are undertaken to produce a homogenate. The biomolecules are next separated from the cell debris by lysate clarification. For extracellular products, the biomolecules are separated from the whole cells by clarification. The overall yield is reduced with each additional step. As the cost of bioseparation process accounts for 50-80% of the final product cost, innovations in and improvement of bio-downstream processing are greatly needed.

In this research, a cyclic process integrating a …


Development And Integration Of A Decision Support System For Electronic Outsourcing Into Telemanufacturing Service Provider, Vikram Batra May 2000

Development And Integration Of A Decision Support System For Electronic Outsourcing Into Telemanufacturing Service Provider, Vikram Batra

Theses

The use of computers and Information Technology enables manufacturers, especially small and medium size enterprises (SMEs) to improve productivity and increase manufactuning flexibility. Telemanufactuning or manufacturing in virtual environment is one of the infrastructures that facilitate the use of information superhighways and computer technology to attain these goals. Broadly defined, Telemanufactuning is the utilization of services accessed via communication networks and across information superhighways to perform in real time, operations and processes essential to the design and production of items. It can be a key enabler for decentralized manufacturing using global resources and expert design teams. In addition to updating …


Design And Fabrication Of Optical Resonators, Pushkar Moholkar May 2000

Design And Fabrication Of Optical Resonators, Pushkar Moholkar

Theses

The design and fabrication of ring optical resonators for high-speed optical communication systems is the topic of this thesis. Its novelty is in two aspects: 1) Use of silicon wafers as an optical guiding medium; 2) Use of wafer bonding technique to attach two optical elements together.

The structure consists of two optical waveguides, the bus waveguide and the drop channel waveguide. A ring on top of these waveguides couples them in such a way that only one narrow spectral line is removed from the bus waveguides which propagates in the drop-channel waveguide. The assembly is fabricated using wafer-bonding technique …


Bounded Beam Wave Pulse Propagation And Scattering In Random Media Based On The Radiative Transfer Theory Using 2-D Gauss Quadrature Formula, Sheng-Kai Hu May 2000

Bounded Beam Wave Pulse Propagation And Scattering In Random Media Based On The Radiative Transfer Theory Using 2-D Gauss Quadrature Formula, Sheng-Kai Hu

Theses

The scalar time-dependent equation of radiative transfer is used to develop a theory of bounded beam wave narrow band pulse propagation and scattering in a medium characterized by many random discrete scatters, which scatters energy strongly in the forward scattering direction. Applications include the scattering of highly collimated millimeter waves in vegetation and optical beams in the atmosphere. The specific problem analyzed is that of a periodic sequence of Gaussian shaped pulses normally incident from free space onto the planar boundary surface of a random medium half-space, such as a forest, that possesses a scatter (phase) function consisting of a …


Numerical Studies Of Deep Bed Filtration, Chan-Gyun Shin May 2000

Numerical Studies Of Deep Bed Filtration, Chan-Gyun Shin

Theses

Deep bed filtration is a process used to separate small solid particles suspended in a fluid by using granular solids as the collecting medium. The filter efficiency depends on many parameters such as the Reynolds number, particle drag coefficient, the ratio of the diameter of injected, and filter particles, etc.

In the present work we model the porous media flow (solution of the Navier-Stokes equations) by using a computer code developed by Dr. P. Singh and we restrict our analysis to the case of two dimensional periodic porous media. The computational domain is discretized using the finite element method. In …


Multimedia Modeling Of Organic Contaminants In The Passaic River Watershed, Lansana Coulibaly May 2000

Multimedia Modeling Of Organic Contaminants In The Passaic River Watershed, Lansana Coulibaly

Dissertations

A dynamic fate and transport multimedia environmental model was developed and applied to assess the release of five priority contaminants in the Passaic River Watershed, including: napthalene, toluene, trichloroethylene, 1-1-1 trichloroethane and xylene. The model uses the current releases of contaminants as well as cross-boundary advection to determine the fate and environmental distribution of these chemicals in the watershed. The model was developed using a dynamic fugacity approach in order to allow for scenario analysis such as source reductions and no-action alternatives. This modeling effort is expected to achieve a comprehensive assessment of contaminants not only in the proximity of …


Electrochemical Quartz Crystal Microbalance Study On The Promoted Electron Transfer Process At Gold Electrode, Xia-Qin Wu, Zhe-Su Wang, Xiao-Yun Meng, Zong-Rang Zhang May 2000

Electrochemical Quartz Crystal Microbalance Study On The Promoted Electron Transfer Process At Gold Electrode, Xia-Qin Wu, Zhe-Su Wang, Xiao-Yun Meng, Zong-Rang Zhang

Journal of Electrochemistry

The adsorption behavior of amino acids, such as L-cysteine, histidine and arginine at gold-quartz crystal microbalance (Au-QCM) was investigated. The adsorption quantity of cysteine is more appreciable than others because of the stronger interaction between its thiol group and the gold electrode surface. The electron-transfer process of superoxide dismutase (SOD) in presence of cysteine at Au-QCM has also been studied using the electrochemical quartz crystal microbalance (EQCM) technique which reveals clearly the quasi-reversible electron-transfer process accompanied by the frequency shift cycle. The reversible adsorption and disorption processes are discussed.


An Investigation On The Corrosion Potential Imaging At The Interface Of Concrete/Reinforcing Bar In Corrosion Media, Rong-Zong Hu, Chang-Jian Lin, Xiang Zhou, Jian-Guang Tan, Xiong-Chao Zhao May 2000

An Investigation On The Corrosion Potential Imaging At The Interface Of Concrete/Reinforcing Bar In Corrosion Media, Rong-Zong Hu, Chang-Jian Lin, Xiang Zhou, Jian-Guang Tan, Xiong-Chao Zhao

Journal of Electrochemistry

The iron array electrode covered with concrete as a new electrochemical technique is applied to map the potential imaging and to investigate on the iron electrode corrosion process under concrete: In Cl- solution the corrosion of the iron array electrode covered with concrete had been prevented for a short term since the concrete protection, but the corrosion still occurreed and developed after immersed for a long time. In SO42- solution although the sample had being immersed for a long time and the concrete was possibly broken, the corrosion did not develop. In Cl- solution the corrosion …


Aqueous Processing And Mechanical Properties Of Plzt Green Tapes, Jian-Huei Feng, Fatih Dogan May 2000

Aqueous Processing And Mechanical Properties Of Plzt Green Tapes, Jian-Huei Feng, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Aqueous tape casting of lanthanum-modified lead zirconate titanate (PLZT) was performed using commercial poly (vinyl alcohol) (PVA) binders and various plasticizers. Colloidal properties of PLZT suspensions containing only polyelectrolyte dispersant were characterized by zeta potential, conductivity, and viscosity measurements. The effects of molecular weight as well as chemical structures of plasticizers and binders on green tapes were investigated by tensile testing. The tapes made from low molecular weight plasticizers showed higher plasticity, and glycerol was found to be the most effective plasticizer for PVA. Strong hydrogen bonding in high hydrolysis PVAs led to green tapes with high strength and high …


Fuzzy (Granular) Levels Of Quality, With Applications To Data Mining And To Structural Integrity Of Aerospace Structures, Roberto A. Osegueda, Carlos Ferregut, Vladik Kreinovich, Seelam Seetharami, Harry Schulte May 2000

Fuzzy (Granular) Levels Of Quality, With Applications To Data Mining And To Structural Integrity Of Aerospace Structures, Roberto A. Osegueda, Carlos Ferregut, Vladik Kreinovich, Seelam Seetharami, Harry Schulte

Departmental Technical Reports (CS)

Experts usually describe quality by using words from natural language such as "perfect", "good", etc. In this paper, we deduce natural numerical values corresponding to these words, and show that these values explain empirical dependencies uncovered in data mining and in the analysis of structural integrity of aerospace structures.


Building The Veco Online Community : A Model For Encouraging Novices., Michelle Williams, Janine Bowes. May 2000

Building The Veco Online Community : A Model For Encouraging Novices., Michelle Williams, Janine Bowes.

Australian Journal of Teacher Education

Building online networks and designing network activity is becoming central to how educators and other education-based professionals work, train others and teach students. It is only since 1995 that Internet connectivity in Australia has provided the critical mass and momentum which alters how people work, who they work with and how they learn. Thus the business of helping professional networks develop and become part of the lives of their members is uncharted territory and an area for research and development for educators in all fields. This paper shares the story of the development of an Australian Network for Vocational Education …


Preliminary Design Of An Electrodynamic Balance For Single Particle Analysis, C. Bobcowski, J. Costa, S. Shaw, R. Zucal, J. Schmalzel, R. Ordonez, John Chen May 2000

Preliminary Design Of An Electrodynamic Balance For Single Particle Analysis, C. Bobcowski, J. Costa, S. Shaw, R. Zucal, J. Schmalzel, R. Ordonez, John Chen

Mechanical Engineering

An electrodynamic chamber (EDC) is a device that controls the electrodynamic field surrounding a single particle. By suspending the particle at a fixed point in space, various measurements can be made to determine thermodynamic properties of the particle. This paper describes the preliminary engineering development of an EDC for combustion research at Rowan University.


Using Raster Sketches For Digital Image Retrieval, James Carswell May 2000

Using Raster Sketches For Digital Image Retrieval, James Carswell

Other resources

This research addresses the problem of content-based image retrieval using queries on image-object shape, completely in the raster domain. It focuses on the particularities of image databases encountered in typical topographic applications and presents the development of an environment for visual information management that enables such queries. The query consists of a user-provided raster sketch of the shape of an imaged object. The objective of the search is to retrieve images that contain an object sufficiently similar to the one specified in the query. The new contribution of this work combines the design of a comprehensive digital image database on-line …