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N-Acylphosphatidylethanolamine in Dry and Imbibing Cottonseeds. Amounts, Molecular Species, and Enzymatic Synthesis (open access)

N-Acylphosphatidylethanolamine in Dry and Imbibing Cottonseeds. Amounts, Molecular Species, and Enzymatic Synthesis

Article on N-acylphosphatidylethanolamine in dry and imbibing cottonseeds.
Date: September 1995
Creator: Sandoval, John A.; Huang, Zhi-Heng; Garrett, David; Gage, Douglas A. & Chapman, Kent D.
System: The UNT Digital Library
High-pressure low-symmetry phases of cesium halides (open access)

High-pressure low-symmetry phases of cesium halides

In this article, the relative stability of different high-pressure phases of various cesium halides is studied from first principles and analyzed using the Landau theory of phase transitions.
Date: April 1, 1995
Creator: Buongiorno Nardelli, Marco; Baroni, Stefano & Giannozzi, Paolo
System: The UNT Digital Library
Field Errors in Hybrid Insertion Devices (open access)

Field Errors in Hybrid Insertion Devices

Hybrid magnet theory as applied to the error analyses usedin the design of Advanced Light Source (ALS) insertion devices isreviewed. Sources of field errors in hybrid insertion devices arediscussed.
Date: February 3, 1995
Creator: Schlueter, R.D.
System: The UNT Digital Library
Crystalline Beam Properties as Predicted for the Storage Ring ASTRID and TSR (open access)

Crystalline Beam Properties as Predicted for the Storage Ring ASTRID and TSR

Employing a previously developed formalism 1, we have performed ground-state and melting calculations of the expected crystalline beams in ion storage rings ASTRID and TSR.
Date: March 1, 1995
Creator: Wei, J.; Li, X. P. & Sessler, Andrew M.
System: The UNT Digital Library
SEPARATION OF TRITIATED WATER FROM WATER USING COMPOSITE MEMBRANES (open access)

SEPARATION OF TRITIATED WATER FROM WATER USING COMPOSITE MEMBRANES

The work in this task involves the use of composite membranes to remove tritium from contaminated water at DOE sites. Experience with membrane systems in industry indicates that they are inherently energy efficient. Furthermore, membrane technologies such as reverse-osmosis have been well developed for desalination and other industrial/municipal applications. Aromatic polyphosphazenes were chosen as the polymeric material for the membranes being investigated because they have excellent radiological, thermal, and chemical stability. The FY-96 effort is directed toward empirical delineation of a potential mechanism, providing a statistical approach to data acquisition, further mass balance determination, and a preliminary design for the module staged array.
Date: December 18, 1995
Creator: JB, DUNCAN & DA, NELSON
System: The UNT Digital Library
Feasibility of Measuring the Cosmological Constant [LAMBDA]and Mass Density [Omega]using Type Ia Supernovae (open access)

Feasibility of Measuring the Cosmological Constant [LAMBDA]and Mass Density [Omega]using Type Ia Supernovae

We explore the feasibility of resurrecting the apparent magnitude-redshift relation for a 'standard candle' to measure the cosmological constant and mass density. We show that type Ia supernovae, if measured with 0.15 mag uncertainty out to a redshift of z = 1, may provide a good standard candle or calibrated candle for this purpose. The recent discovery of probable type Ia supernovae in the redshift range z = 0.3 to 0.5 (Perlmutter et al. 1994a, and 1994b) indicates that the flux of optical photons from these events can be measured this accurately. The 7 distant supernovae discovered to date do not by themselves distinguish between different cosmological models, however the further discovery of about 50 type Ia supernovae at redshifts in the range 0.5 < z {approx} 1.0 could strongly constrain the allowed range of these parameters. We estimate that the follow-up photometry necessary for this measurement would be on the order of 20 - 70 hours of time on a lO-meter class telescope at a site with good seeing.
Date: April 1, 1995
Creator: Goobar, A. & Perlmutter, S.
System: The UNT Digital Library
Use of Volatile Tracers to Determine the Contribution ofEnvironment Tobacco Smoke to Concentrations of Volatile Organic Compoundsin Smoking Environments (open access)

Use of Volatile Tracers to Determine the Contribution ofEnvironment Tobacco Smoke to Concentrations of Volatile Organic Compoundsin Smoking Environments

Three volatile nitrogen-containing compounds, 3-ethenylpyridine (3-EP), pyridine and pyrrole, were investigated as potential tracers for determining the contribution of environmental tobacco smoke (ETS) to concentrations of volatile organic compounds (VOCs) in indoor environments with smoking. The source emission rates of the three tracers and ten selected VOCs in ETS were first measured in a room-size environmental chamber for a market-weighted selection of six commercial cigarettes. The ratios of the emission rates of the tracers to the emission rates of the selected VOCs were calculated and compared among the six brands. The utility of the tracers was then evaluated in a field study conducted in five office buildings. Samples for VOCs were collected in designated smoking areas and adjoining non-smoking areas, air change rates were measured, and smoking rates were documented. Concentrations of the three tracers in the smoking areas were calculated using a mass-balance model and compared to their measured concentrations. Based on this comparison, 3-EP was selected as the most suitable tracer for the volatile components of ETS, although pyrrole is also potentially useful. Using 3-EP as the tracer, the contributions of ETS to the measured concentrations of the selected VOCs in the smoking areas were estimated by apportionment. …
Date: December 1, 1995
Creator: Hodgson, A. T.; Daisey, J. M.; Alevantis, L. E.; Mahanama, K. R. R. & Ten Brinke, J.
System: The UNT Digital Library
A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry (open access)

A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry

Photometric measurements show that, as a group, nearby Type Ia supernovae follow similar light curves and reach similar peak magnitudes (Branch & Tammann 1992). Thus, these supernovae may serve as standard candles or calibrated candles at cosmological distances. Magnitudes of local and distant supernovae, both in the same filter band, are compared using a K correction to account for the different spectral regions incident on that filter. A generalized approach compares magnitudes in different bands for the nearby and distant supernovae, bands that are selected to give sensitivity in corresponding regions of the unredshifted and redshifted spectra. Thus, R magnitudes for supernovae at z {approx} 0.5 are compared with B magnitudes of local supernovae. We compute these generalized K corrections over a range of redshifts and bandpass pairs and discuss their advantages over the traditional single-band K correction. In particular, errors near maximum light can be kept below 0.05 mag out to at least z = 0.6, whereas the traditional K correction is less accurate and can be difficult to determine beyond z > 0.2.
Date: November 1, 1995
Creator: Kim, Alex; Goodbar, Ariel & Perlmutter, Saul
System: The UNT Digital Library
Four Papers by the Supernova Cosmology Project (open access)

Four Papers by the Supernova Cosmology Project

Our search for high-redshift Type Ia supernovae discovered, in its first years, a sample of seven supernovae. Using a 'batch' search strategy, almost all were discovered before maximum light and were observed over the peak of their light curves. The spectra and light curves indicate that almost all were Type Ia supernovae at redshifts z = 0.35 - 0.5. These high-redshift supernovae can provide a distance indicator and 'standard clock' to study the cosmological parameters q{sub 0}, {Lambda}, {Omega}{sub 0}, and H{sub 0}. This presentation and the following presentations of Kim et al. (1996), Goldhaber et al. (1996), and Pain et al. (1996) will discuss observation strategies and rates, analysis and calibration issues, the sources of measurement uncertainty, and the cosmological implications, including bounds on q{sub 0}, of these first high-redshift supernovae from our ongoing search.
Date: June 1, 1995
Creator: Perlmutter, S. & al., et
System: The UNT Digital Library
Design of a relativistic Klystron Two-Beam Accelerator Prototype (open access)

Design of a relativistic Klystron Two-Beam Accelerator Prototype

We are designing an experiment to study physics, engineering, and costing issues of an extended Relativistic Klystron Two-Beam Accelerator (RK-TBA). The experiment is a prototype for an RK-TBA based microwave power source suitable for driving a 1 TeV linear collider. Major components of the experiment include a 2.5-MV, 1.5-kA electron source, a 11.4-GHz modulator, a bunch compressor, and a 8-m extraction section. The extraction section will be comprised of 4 traveling-wave output structures, each generating about 360 MW of rf power. Induction cells will be used in the extraction section to maintain the average beam energy at 5 MeV. Status of the design is presented.
Date: April 1, 1995
Creator: Westenskow, G.; Caporaso, G.; Chen, Y.; Houck, T.; Yu, S.; Chattopadhyay, S. et al.
System: The UNT Digital Library
Improving plasma shaping accuracy through consolidation of control model maintenance, diagnostic calibration, and hardware change control (open access)

Improving plasma shaping accuracy through consolidation of control model maintenance, diagnostic calibration, and hardware change control

With the advent of more sophisticated techniques for control of tokamak plasmas comes the requirement for increasingly more accurate models of plasma processes and tokamak systems. Development of accurate models for DIII-D power systems, vessel, and poloidal coils is already complete, while work continues in development of general plasma response modeling techniques. Increased accuracy in estimates of parameters to be controlled is also required. It is important to ensure that errors in supporting systems such as diagnostic and command circuits do not limit the accuracy of plasma parameter estimates or inhibit the ability to derive accurate plasma/tokamak system models. To address this issue, we have developed more formal power systems change control and power system/magnetic diagnostics calibration procedures. This paper discusses our approach to consolidating the tasks in these closely related areas. This includes, for example, defining criteria for when diagnostics should be re-calibrated along with required calibration tolerances, and implementing methods for tracking power systems hardware modifications and the resultant changes to control models.
Date: December 1, 1995
Creator: Baggest, D. S.; Rothweil, D. A.; Pang, S.; Walker, M. L. & Nerem, A.
System: The UNT Digital Library
Multidimensional DDT modeling of energetic materials (open access)

Multidimensional DDT modeling of energetic materials

A nonequilibrium continuum mixture model has been incorporated into the CTH shock physics code to describe deflagration-to-detonation transition in granular energetic materials. This approach treats multiple thermodynamic and mechanics fields including the effects of relative material motion, rate-dependent compaction and interphase exchange of mass, momentum and energy. A finite volume description is formulated and internal state variables are solved using an operator-splitting method. Numerical simulations of low-velocity impact on a weakly-confined porous propellant bed are presented which display lateral wall release leading to curved compaction and reaction wave behavior.
Date: August 1, 1995
Creator: Baer, M. R.; Hertel, E. S. & Bell, R. L.
System: The UNT Digital Library
Orientation selection and microstructural evolution of epitaxial platinum films on (001) magnesium oxide (open access)

Orientation selection and microstructural evolution of epitaxial platinum films on (001) magnesium oxide

Thin platinum films were deposited at several different deposition rates and with varying thickness on (001)-cut MgO single crystal substrates by electron beam evaporation. A mixture of two epitaxial Pt orientations were detected in the films by X-ray diffraction and planar ion channeling experiments: (001)[100]Pt // (001)[100]MgO (the [open quotes]cube-on-cube[close quotes] orientation) and (111)[110]Pt // (001)[110]MgO. The effect of deposition rate on film orientation indicated the (111)Pt orientation was preferred under conditions of high driving force for nucleation. The volume fraction of the films occupied by the (111) orientation increased with nominal film thickness, at a constant substrate temperature and deposition rate. This result indicates crystallites having the (111)Pt orientation grew more quickly following nucleation than the (001). The mosaic spread of the Pt orientation decreased markedly as the nominal film thickness increased from [approximately] 1.5 nm (isolated islands) to 20 nm (continuous film).
Date: January 1, 1995
Creator: McIntyre, P.C.; Maggiore, C.J. & Natasi, M.
System: The UNT Digital Library
[Support you local museum, June 11, 1995] (open access)

[Support you local museum, June 11, 1995]

An article written by Janet Tyson about the need to support local museums. The Amon Carter Museum is featured in the piece.
Date: June 11, 1995
Creator: Tyson, Janet
System: The UNT Digital Library
[Fort Worth Star-Telegram, July 7-13, 1995] (open access)

[Fort Worth Star-Telegram, July 7-13, 1995]

An article in the Fort Worth Star-Telegram about the upcoming collections and events at the Amon Carter Museum in Fort Worth. It is titled Little Journeys and has information about tours and group visits.
Date: [1995-07-07..1995-07-13]
Creator: Fort Worth Star-Telegram
System: The UNT Digital Library
[Amon Carter director resigns after 15 years] (open access)

[Amon Carter director resigns after 15 years]

An article written by Janet Kutner, the art critic for The Dallas Morning News, covering the resignation of Jan Muhlert from the Amon Carter Museum. It gives a short history of Muhlert's time at the museum and words from past co-workers.
Date: 1995
Creator: Kutner, Janet
System: The UNT Digital Library
[Fort Worth Star-Telegram Arts & Entertainment, January 30, 1995] (open access)

[Fort Worth Star-Telegram Arts & Entertainment, January 30, 1995]

An article written by Janet Tyson for the Arts & Entertainment section of the Fort Worth Star-Telegram titled 'Thumbnail Sketch'. The piece is a snapshot of who Dr. R. William McCarter is with direct quotes from him.
Date: January 30, 1995
Creator: Tyson, Janet
System: The UNT Digital Library
[Life and Arts, September 16, 1995] (open access)

[Life and Arts, September 16, 1995]

An article titled "School of Thought" written by Janet Tyson for the Life & Arts section of the Fort Worth Star Telegram. It covers a group of fifth-graders while they visit the at museums in the Fort Worth area.
Date: September 16, 1995
Creator: Tyson, Janet
System: The UNT Digital Library
[UNT InHouse, Vol. 4, No. 3, March 1995] (open access)

[UNT InHouse, Vol. 4, No. 3, March 1995]

An article written by Cass Brunner for UNT InHouse about a grant from the Edward and Betty Marcus Foundation that was awarded to the NTIEVA program in partnership with the Dallas Museum of Art. The grant totals $784,277 and aims to fund improvements and initiatives in the two groups.
Date: March 1995
Creator: Brunner, Cass
System: The UNT Digital Library
[UNT graduate students take center stage, April 9, 1995] (open access)

[UNT graduate students take center stage, April 9, 1995]

An article written by April M. Washington for the Denton Record-Chronicle that covers two graduate students from UNT, Bader Alruwais and Matthew Mailman. Alruwais received the Prince Bandar ibn Sultan Annual Award for Cultural and Scientific Research and Mailman is conducting a recital performance.
Date: April 9, 1995
Creator: Washington, April M.
System: The UNT Digital Library
[Art Smart article, April 9, 1995] (open access)

[Art Smart article, April 9, 1995]

An article from the Fort Worth Star-Telegram written by Clara Herrera. The article covers Brandon Lewis and other students in art classes and the logistics behind what courses are available to them.
Date: April 9, 1995
Creator: Herrera, Clara G.
System: The UNT Digital Library
Technical and policy issues related to semantically and spatially incompatible geodata (open access)

Technical and policy issues related to semantically and spatially incompatible geodata

Both the Intelligent Transportation Systems (ITS) and National Information Infrastructure (NU) efforts have ambitious goals that are expected to improve the fundamental infrastructure, commerce, and society of the United States. Achieving these goals will require rapid development and deployment of information compatibility methods through technical and institutional standards. These standards will have to be scaleable and flexible to support new, and as-yet-undiscovered, data. Yet they will also need to accommodate our valuable data reserves. The area of geospatial data, and thus the creation of a National Spatial Data Infrastructure (NSDI), is particularly challenging due to the profoundly different forms, evolutionary histories, and meanings attached to spatial data. We discuss technical issues resulting from the different natures and inaccuracy of existing geodata, and areas where federal policy could lead the way to greater compatibility.
Date: July 1, 1995
Creator: Bespalko, Stephen J.; Ganter, John H. & Van Meter, Marsha D.
System: The UNT Digital Library
Advanced turbine cooling, heat transfer, and aerodynamic studies (open access)

Advanced turbine cooling, heat transfer, and aerodynamic studies

The contractual work is in three parts: Part I - Effect of rotation on enhanced cooling passage heat transfer, Part II - Effect of Thermal Barrier Coating (TBC) spallation on surface heat transfer, and Part III - Effect of surface roughness and trailing edge ejection on turbine efficiency under unsteady flow conditions. Each section of this paper has been divided into three parts to individually accommodate each part. Part III is further divided into Parts IIIa and IIIb.
Date: December 31, 1995
Creator: Han, Je-Chin & Schobeiri, Meinhard T.
System: The UNT Digital Library
Measurement of ultrashort pulses with a non-instantaneous nonlinearity (open access)

Measurement of ultrashort pulses with a non-instantaneous nonlinearity

We show how non-instantaneous nonlinearities can be used to characterize an ultrashort pulse in an extension of the Frequency-Resolved Optical Gating technique. We demonstrate this principle using the Raman effect in fused silica.
Date: February 1, 1995
Creator: DeLong, K. W.; Ladera, C. L.; Trebino, R.; Kohler, B. & Wilson, K. R.
System: The UNT Digital Library