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"Quadrupolar" Molecular Nonlinear Optics, V. Ostroverkhov, O. Ostroverkhova, Kenneth D. Singer, L. Sukhomlinova, R. J. Twieg May 1999

"Quadrupolar" Molecular Nonlinear Optics, V. Ostroverkhov, O. Ostroverkhova, Kenneth D. Singer, L. Sukhomlinova, R. J. Twieg

Faculty Scholarship

Quadrupolar and octupolar invariants may be used as methods to attain noncentrosymmetric materials for application in second order nonlinear optics. The structure-property relationships for the J = 2, or quadrupole rotational invariant, are investigated. Proper citation for the Technical Digest CD-ROM should be written in the following format: Ostrovekhov V., Ostroverkhova O., Petschek R.G., Singer K.D., Sukhomlinova L., Twieg R.J., “`Quadrupolar' molecular nonlinear optics,” in the Conference on Lasers and Electro-Optics (CLEO)/The International Quantum Electronics Conference (IQEC) (Optical Society of America, Washington, DC, 2009), Proceedings, 8-9


Particle Sizing In Strongly Turbid Suspensions With The One-Beam Cross-Correlation Dynamic Light-Scattering Technique, Anthony J. Adorjan, James A. Lock, Thomas W. Taylor, Padetha Tin, William V. Meyer, Anthony E. Smart May 1999

Particle Sizing In Strongly Turbid Suspensions With The One-Beam Cross-Correlation Dynamic Light-Scattering Technique, Anthony J. Adorjan, James A. Lock, Thomas W. Taylor, Padetha Tin, William V. Meyer, Anthony E. Smart

Physics Faculty Publications

The utility of the one-beam cross-correlation dynamic light-scattering system for sizing small particles in suspension was previously limited by its small-intensity signal-to-baseline ratio for strongly turbid suspensions. We describe three improvements in the optical system and sample cell that raise the ratio to a value comparable with that of other cross-correlation dynamic light-scattering systems. These improvements are (i) using a square cross-sectional sample cell to minimize the attenuation of the incident beam and singly scattered light, (ii) placing a 200-mu m-wide slit between the sample cell and the detector fibers to mask off the region of weak single scattering and …


Modeling The High-Speed Switching Of Far-Infrared Radiation By Photoionization In A Semiconductor, Thomas E. Wilson May 1999

Modeling The High-Speed Switching Of Far-Infrared Radiation By Photoionization In A Semiconductor, Thomas E. Wilson

Physics Faculty Research

Data from an earlier study [T. Vogel et al., Appl. Opt. 31, 329 (1992)] on the subnanosecond switching of 119-μm radiation in high-resistivity silicon by pulsed UV laser radiation, is compared with a refined one-dimensional numerical multilayer model accounting for the generation, recombination, and diffusion of the free carriers on the resulting far-infrared optical properties of the silicon. The inclusion of recent measurements for carrier-density and temperature-dependent transport parameters leads to improved agreement between experiment and theory.


Plant And Soil Enantioselective Biodegradation Of Racemic Phenoxyalkanoic Herbicides, J. M. Schneiderheinze, Daniel W. Armstrong, Alain Berthod May 1999

Plant And Soil Enantioselective Biodegradation Of Racemic Phenoxyalkanoic Herbicides, J. M. Schneiderheinze, Daniel W. Armstrong, Alain Berthod

Chemistry Faculty Research & Creative Works

The biodegradation of the chiral phenoxyalkanoic herbicides 2-(2,4- dichlorophenoxy)propionic aid (2,4-DP) and 2-(4-chloro-2- methylphenoxy)propionic acid (MCPP) was investigated using enantioselective HPLC and chiroptical detection. Racemic mixtures of 2,4-DP and MCPP were applied to three species of turf grass, four species of broadleaf weeds, and soil. Preferential degradation of the S- (-) enantiomer of each herbicide was observed in most species of broadleaf weeds and soil, while the degradation in all species of grass occurred without enantioselectivity. The biodegradation in all systems appeared to follow pseudo first-order kinetics with the fastest degradation occurring in broadleaf weeds, followed by the grasses. The …


Proposals For Community Discussion. A Quality Future For Recreational Fishing In The Gascoyne. A Five-Year Management Strategy For Recreational Fishing., Gascoyne Recreational Fishing Working Group May 1999

Proposals For Community Discussion. A Quality Future For Recreational Fishing In The Gascoyne. A Five-Year Management Strategy For Recreational Fishing., Gascoyne Recreational Fishing Working Group

Fisheries Management Papers

Gascoyne has seen a series of rapid developments in recreational fisheries management, starting with the introduction of state-wide bag limits in 1991; followed by area specific controls at Ningaloo in 1992; landing limits in Exmouth Gulf in 1993; strict controls on the take of pink snapper in Shark Bay’s inner gulfs in 1997; new bag limits for Shark Bay in 1998; and the introduction of a management system for the charter and aquatic tour industry in 1999. The management proposals presented for community discussion in this paper are aimed at maintaining or improving the quality and diversity of the Gascoyne's …


Analysis Of Fats And Fat-Soluble Components In Foods Using Supercritical Fluid Extraction And Chromatographic Techniques, Sneha Patel May 1999

Analysis Of Fats And Fat-Soluble Components In Foods Using Supercritical Fluid Extraction And Chromatographic Techniques, Sneha Patel

Masters Theses & Specialist Projects

The purpose of this study was to develop experimental procedures for the extraction of fats from common foods using SFE and to determine by chromatographic techniques the fat-soluble components that are extracted with the fats. In this study various food samples were examined including french fries from Wendy's, McDonald's and Burger King, as well as potato chips, peanut butter and donuts. Soxtec extraction was used as the standard method for comparison of results (percentage of fat) obtained from SFE. Gas chromatography and gas chromatography/mass spectrometry were used for the determination of fat-soluble components (fatty acids), after extraction of fat from …


Santa Clara Magazine, Volume 41 Number 1, May 1999, Santa Clara University May 1999

Santa Clara Magazine, Volume 41 Number 1, May 1999, Santa Clara University

Santa Clara Magazine

8 - A BRIDGE BETWEEN WORLDS By President PaulL. Locatelli, S.J. 'Go. President Locatelli examines the value of service learning for students, the University, and America's social fabric.

12 - A GIANT ARTIST By Ann Granning Bennett. Auguste Rodin's sculptures are now on view at the de Saisset Museum. The question is: How do high-profile art shows like this one come about?

18 - ARIZONA'S DIPLOMATIC TOP COP By Tamara Straus. Janet Napolitano ' 79 , Arizona's newly elected attorney general , discusses the challenges of public office as well as politics, ethics, and fighting crime.


Integrated Management Systems For Australian White Ibis (Threskiornis Molucca) On The Gold Coast, Queensland, Australia, Phillip P. Shaw May 1999

Integrated Management Systems For Australian White Ibis (Threskiornis Molucca) On The Gold Coast, Queensland, Australia, Phillip P. Shaw

Bird Strike Committee-USA/Canada Joint Annual Meeting: 1st (1999)

Fueled by a large supplemental food supply at landfills in South-east Queensland, Australian White Ibis (Threskiornis molucca) populations grew from an estimated 5000 to 10000 between 1995 and 1998. Ibis counted at Coolangatta Airport reflected this growth with a 556% increase between 1989 and 1995. The multimillion-dollar loss of a Qantas airbus engine from ingestion of an Ibis, resulted in the establishment of the Ibis Management Coordination Group (IMCG). This group, comprising government, industry and community representatives, instigated an integrated program of food reduction, restriction of breeding success and public education. The program has become an example for management programs …


Zero Bird-Strike Rate - An Achievable Target, Not A Pipedream, S. M. Satheesan May 1999

Zero Bird-Strike Rate - An Achievable Target, Not A Pipedream, S. M. Satheesan

Bird Strike Committee-USA/Canada Joint Annual Meeting: 1st (1999)

This paper explains how zero bird-strike rate can be achieved by any aerodrome by constant efforts and perseverance of a dedicated team as evidenced from the author’s experience on about 30 aerodromes in India. This paper stresses the importance of conducting survey of problem aerodromes every five years by an expert (Satheesan 1996c), necessity for employing an Ornithologist at every aerodrome, need for regular national-level training for bird-controllers (Satheesan, in press - b) and urgency for setting up Bird-strike Prevention Committees at national (interministerial) and airport levels. Bird strike rates were brought down to zero at the Trivandrum International Airport …


Raising Public Awareness Of Bird Strike Risk Issues With An Enhanced Bird Strike Committee Usa Web Site, Todd Curtis May 1999

Raising Public Awareness Of Bird Strike Risk Issues With An Enhanced Bird Strike Committee Usa Web Site, Todd Curtis

Bird Strike Committee-USA/Canada Joint Annual Meeting: 1st (1999)

Since 1997, a World Wide Web site managed by a member of Bird Strike Committee USA and a site managed by the Committee leadership were instrumental in supporting Committee efforts to reduce these hazards. Based on insights gained from these two Web sites, a new site was created that contained the most effective elements of the earlier sites and new elements designed to enhance the ability of the Committee to accomplish its mission. The new elements included the acquisition and use of the domain name birdstrike.org, the ability to electronically submit bird and other wildlife strike reports directly into the …


An On-Line Test For Polycyclic Aromatic Hydrocarbons In The Flue Gas From Coal Combustion In An Fbc System, Wenjun Han May 1999

An On-Line Test For Polycyclic Aromatic Hydrocarbons In The Flue Gas From Coal Combustion In An Fbc System, Wenjun Han

Masters Theses & Specialist Projects

Polycyclic Aromatic Hydrocarbons (PAHs) are environmental pollutants that have received considerable attention because of their carcinogenic and mutagenic effects. Due to the extensive amount of data suggesting the hazards of these compounds, 16 PAHs are on the Environmental Protection Agency (EPA) Priority Pollutant List. These compounds are often emitted into the atmosphere by way of combustion processes. Thus, analysis of these compounds during coal combustion is an important task. Three 1000-hour coal combustion burns were performed using the 0.1 MW (0.3 m) bench-scale Fluidized Bed Combustor (FBC) in the Combustion Laboratory at Western Kentucky University. The data for this thesis …


Center For Sustainable Agricultural Systems Newsletter, May/June 1999 May 1999

Center For Sustainable Agricultural Systems Newsletter, May/June 1999

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

The Farmer and the Dean

University Role in Biotechnology: Who Owns Genes and Diversity?

CSAS Volume 9 Discusses Watersheds

SARE Appoints Paula Ford North Central PDP

Coordinator Policy Project Identifies Retention of Farms and Farmland as Top Priorities

Olson Heads to Kentucky

Organic Grain Farming Workshops

Two Alternative Agriculture Conferences in Midwest


The Effect Of Laser Bandwidth On The Signal Detected In Two-Color, Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack May 1999

The Effect Of Laser Bandwidth On The Signal Detected In Two-Color, Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack

Physics Faculty Research and Scholarship

The effect of laser line shape and bandwidth on the signal detected in two-color, resonant four-wave mixing (TC-RFWM) spectroscopy is determined by means of an ab initio calculation of the third-order polarization based on diagrammatic perturbation theory. Modifications to the approach previously used for the case of delta-function laser line shapes are made by introducing a different treatment of the rotating wave approximation and phase-matching conditions. A three-level excitation scheme for double-resonance spectroscopy of bound and quasibound states is analyzed. In the case of Lorentzian laser line shapes, analytic expressions for the signal line profile are obtained for each excitation …


An Investigation Into The Use Of The Virtual Reality Modelling Language (Vrml) As A Means Of Distribution Virtual Reality Tourist Information Across The World Wide Web, Hugh Mcatamney, Ciaran Mcdonnell May 1999

An Investigation Into The Use Of The Virtual Reality Modelling Language (Vrml) As A Means Of Distribution Virtual Reality Tourist Information Across The World Wide Web, Hugh Mcatamney, Ciaran Mcdonnell

Conference papers

The purpose of the work described was to investigate the use of the Virtual Reality Modelling Language (VRML) as a tool to distribute tourist information across the web. This was done by the creation of a web site containing two Virtual Reality models of tourist interest. These were then valuated using a number of techniques both online and offline. This paper describes the methods used to create and evaluate these models as well as giving a overview of some of the results obtained.


Insight Into The Selectivity Of Molecular Imprinted Polymers, Thomas Patrick O'Brien May 1999

Insight Into The Selectivity Of Molecular Imprinted Polymers, Thomas Patrick O'Brien

Seton Hall University Dissertations and Theses (ETDs)

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Biological Metaphors In He Design Of Complex Software Systems, Dan C. Marinescu, Ladislau Bölöni May 1999

Biological Metaphors In He Design Of Complex Software Systems, Dan C. Marinescu, Ladislau Bölöni

Department of Computer Science Technical Reports

No abstract provided.


Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca May 1999

Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cultures. The amo genes have excellent potential as molecular markers; since AMO is only found in the AOB and is essential for their metabolism, …


Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad May 1999

Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although considerable research has addressed effects of elevated ultraviolet-B (UV-8) radiation on vegetative plant structures and processes, the reproductive biology and patterns of inheritance of UV-B tolerance have received much less attention. I examined the effects of UV-B radiation on pollen of 34 taxa. I also addressed questions concerning the patterns of inheritance of UV-B tolerance in Arabidopsis thaliana and examined potential cumulative carryover effects of UV-B exposure through multiple generations of this species.

In the first study, a significant reduction in pollen germination occurred in only five species, but pollen tube growth in more than half of the species …


The Open Source Revolution: Transforming The Software Industry With Help From The Government, Mitchell L. Stoltz Apr 1999

The Open Source Revolution: Transforming The Software Industry With Help From The Government, Mitchell L. Stoltz

Pomona Senior Theses

A new method for making software is stealthily gaining ground in the computer industry, offering a promise of better, cheaper software and the empowerment of the user. The open source movement could revolutionize the software industry...if it succeeds. Open source means software that you are allowed to copy, modify, and give to friends. Source code , the lists of instructions which tell computers how to run, is readily available, allowing you to look inside the workings of a program and change it to suit your needs. A group of programmers, companies, users, and activists have gathered in support of this …


How Proteins Fold, Flex, And Bind Other Molecules, Leslie A. Kuhn, Volker Schnecke, Michael L. Raymer, Paul C. Sanschagrin Apr 1999

How Proteins Fold, Flex, And Bind Other Molecules, Leslie A. Kuhn, Volker Schnecke, Michael L. Raymer, Paul C. Sanschagrin

Kno.e.sis Publications

No abstract provided.


Proceedings Of The 1999 Onr Decision-Support Workshop Series: A Decision-Making Tools Workshop, Collaborative Agent Design Research Center Apr 1999

Proceedings Of The 1999 Onr Decision-Support Workshop Series: A Decision-Making Tools Workshop, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

The rationale of the Workshop rests on some very simple observations. It is well known that every situation encountered by individuals and organizations demands an appropriate response. The choice of such a response from among a multitude of options is the decision-making process. Simple situations that give rise to a small number of options allow the decision maker to decide on a course of action without great effort. This state of affairs changes dramatically when the situations are complex and involve a large number of factors. In this case, an extensive field of options is engendered that makes it impossible …


Collaborative Decision-Support And The Human-Machine Relationship, Jens G. Pohl Apr 1999

Collaborative Decision-Support And The Human-Machine Relationship, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Human beings are inquisitive creatures who seek explanations for all that they observe and experience in their living environment. While this quest for understanding is central to our success in adapting to a changing environment, it is also a major cause of our willingness to accept partial understandings and superficial explanations when the degree of complexity of the problem situation confounds our current cognitive capabilities. In other words, a superficial or partial explanation is considered better than no explanation at all. As flawed as this approach may be, it has helped us to solve difficult problems in stages. By first …


Structural And Magnetic Properties Of Nanocomposite Co:C Films, M. Yu, Yi Liu, David J. Sellmyer Apr 1999

Structural And Magnetic Properties Of Nanocomposite Co:C Films, M. Yu, Yi Liu, David J. Sellmyer

David Sellmyer Publications

The structural and magnetic properties of Co:C nanocomposite films at room temperature were investigated as functions of annealing temperature, Co concentration, and film thickness. The as-deposited films, which were cosputtered from Co and C onto water-cooled glass substrates, are nonmagnetic amorphous Co–C alloys. Hexagonal-close-packed (hcp) Co grains are formed in 100 nm films annealed at 300 °C and most Co takes this structure when annealed at higher temperatures. The sizes of the Co grains range from 10 to 25 nm, with larger grain size resulting from higher annealing temperature and higher Co concentration. With the increase of annealing temperature and …


Enhancement Of Coercivity In Nanometer-Size Copt Crystallites, Sy_Hwang Liou, S. Huang, Elizabeth S. Klimek, Roger D. Kirby Apr 1999

Enhancement Of Coercivity In Nanometer-Size Copt Crystallites, Sy_Hwang Liou, S. Huang, Elizabeth S. Klimek, Roger D. Kirby

Roger Kirby Publications

In this study, we showed that a magnetic coercivity (Hc) as high as 37 kOe was obtained in a CoPt thin film that contains separated nanometer-size CoPt crystallites. We prepared CoPt thin films with thicknesses of 5 and 175 nm by magnetron sputtering. After annealing in an Ar/H2 atmosphere at temperatures from 650 to 750 °C for 3–12 h, we measured the magnetic properties and found that magnetic Hc relates to annealing temperature, annealing time and film thickness. From atomic force microscopy and magnetic force microscopy studies, the magnetic single domain size of CoPt is …


Effects Of Layer Thickness On Orientation Distribution And Magnetic Properties Of Cocrta/Cr Films, Z. S. Shan, H. Zeng, C. X. Zhu, M. Azarisooreh, K. Honardoost, Yi Liu, David J. Sellmyer Apr 1999

Effects Of Layer Thickness On Orientation Distribution And Magnetic Properties Of Cocrta/Cr Films, Z. S. Shan, H. Zeng, C. X. Zhu, M. Azarisooreh, K. Honardoost, Yi Liu, David J. Sellmyer

David Sellmyer Publications

No abstract provided.


Activation Entropy, Activation Energy, And Magnetic Viscosity, Ralph Skomski, Roger D. Kirby, David J. Sellmyer Apr 1999

Activation Entropy, Activation Energy, And Magnetic Viscosity, Ralph Skomski, Roger D. Kirby, David J. Sellmyer

Roger Kirby Publications

Starting from an exact quantum-statistical description, the influence of the shape of the energy landscape on the magnetic viscosity is investigated. Magnetic phase-space analysis based on Kramers’ escape-rate theory of chemical reaction kinetics theory shows that the activation entropy associated with thermally activated hopping modifies the magnetic viscosity by reducing the attempt-frequency prefactor compared to an earlier prediction by Brown [W. F. Brown, Phys. Rev. 130, 1677 (1963)]. Energetic contributions are analyzed in terms of a model applicable to a range of coherent and noncoherent magnetization processes, and in the long-time limit deviations from the linear logarithmic magnetic-viscosity law are …


Effects Of Layer Thickness On Orientation Distribution And Magnetic Properties Of Cocrta/Cr Films, Z.S. Shan, H. Zeng, C.X. Zhu, M. Azarisooreh, K. Honardoost Apr 1999

Effects Of Layer Thickness On Orientation Distribution And Magnetic Properties Of Cocrta/Cr Films, Z.S. Shan, H. Zeng, C.X. Zhu, M. Azarisooreh, K. Honardoost

David Sellmyer Publications

Evolution of orientation distribution of Co(110) crystal planes was determined by x-ray rocking curves. It has been found that: (i) The full-width at half maximum W of the Co(110) rocking curve decreases with both increasing Cr underlayer thickness dcr, and increasing CoCrTa magnetic layer thickness dco, especially in the thin layer regime. (ii) For the thin dcoregime, the interlayer diffusion between the Cr underlayer and the magnetic layer affects the rocking curves and magnetic properties significantly. (iii) Film magnetic properties, e.g., a significant jump in coercivity with increasing magnetic layer thickness in the thin …


Evaluation Of Real-Time Fiber Communications For Parallel Collective Operations, Amy Apon, Parvathi Rajagopal Apr 1999

Evaluation Of Real-Time Fiber Communications For Parallel Collective Operations, Amy Apon, Parvathi Rajagopal

Publications

Real-Time Fiber Communications (RTFC) is a gigabit speed network that has been designed for damage tolerant local area networks. In addition to its damage tolerant characteristics, it has several features that make it attractive as a possible interconnection technology for parallel applications in a cluster of workstations. These characteristics include support for broadcast and multicast messaging, memory cache in the network interface card, and support for very fine grain writes to the network cache. Broadcast data is captured in network cache of all workstations in the network providing a distributed shared memory capability. In this paper, RTFC is introduced. The …


The Rate-Based Execution Model, Kevin Jeffay, Steve Goddard Apr 1999

The Rate-Based Execution Model, Kevin Jeffay, Steve Goddard

School of Computing: Technical Reports

We present a new task model for the real-time execution of event-driven tasks in which no a priori characterization of the actual arrival rates of events is known; only the expected arrival rates of events is known. We call this new task model rate-based execution (RBE), and it is a generalization of the common sporadic task model. The RBE model is motivated naturally by distributed multimedia and digital signal processing applications.
We identify necessary and sufficient conditions for determining the feasibility of an RBE task set, and an optimal scheduling algorithm (based on preemptive earliest-deadline-first (EDF) scheduling) for scheduling the …


Spring 1999, Nsu Oceanographic Center Apr 1999

Spring 1999, Nsu Oceanographic Center

Currents

No abstract provided.