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Response to the comments by J.R. Southon and R.E. Taylor on 'terrestrial evidence of a nuclear catastrophe in paleoindian times' (open access)

Response to the comments by J.R. Southon and R.E. Taylor on 'terrestrial evidence of a nuclear catastrophe in paleoindian times'

None
Date: January 28, 2002
Creator: Firestone, Richard B.
System: The UNT Digital Library
Donor and acceptor concentrations in degenerate InN (open access)

Donor and acceptor concentrations in degenerate InN

A formalism is presented to determine donor (N{sub D}) and acceptor (N{sub A}) concentrations in wurtzitic InN characterized by degenerate carrier concentration (n) and mobility ({mu}). The theory includes scattering not only by charged point defects and impurities, but also by charged threading dislocations, of concentration N{sub dis}. For an 0.45-{micro}m-thick InN layer grown on Al{sub 2}O{sub 3} by molecular beam epitaxy, having N{sub dis} = 5 x 10{sup 10} cm{sup -2}, determined by transmission electron microscopy, n(20 K) = 3.5 x 10{sup 18} cm{sup -3}, and {mu}(20 K) = 1055 cm{sup 2}/V-s, determined by Hall-effect measurements, the fitted values are N{sub D} = 4.7 x 10{sup 18} cm{sup -3} and N{sub A} = 1.2 x 10{sup 18} cm{sup -3}. The identities of the donors and acceptors are not known, although a comparison of N{sub D} with analytical data, and also with calculations of defect formation energies, suggests that a potential candidate for the dominant donor is H.
Date: January 28, 2002
Creator: Look, D. C.; Lu, H.; Schaff, W. J.; Jasinski, J. & Liliental-Weber, Z.
System: The UNT Digital Library
Semiconductor nanorod liquid crystals (open access)

Semiconductor nanorod liquid crystals

Rodlike molecules form liquid crystalline phases with orientational order and positional disorder. The great majority of materials in which liquid crystalline phases have been observed are comprised of organic molecules or polymers, even though there has been continuing and growing interest in inorganic liquid crystals. Recent advances in the control of the sizes and shapes of inorganic nanocrystals allow for the formation of a broad class of new inorganic liquid crystals. Here we show the formation of liquid crystalline phases of CdSe semiconductor nanorods. These new liquid crystalline phases may have great importance for both application and fundamental study.
Date: January 28, 2002
Creator: Li, Liang-shi; Walda, Joost; Manna, Liberato & Alivisatos, A. Paul
System: The UNT Digital Library
Study of metal dusting mechanism in iron using Raman spectroscopy and x-ray diffraction. (open access)

Study of metal dusting mechanism in iron using Raman spectroscopy and x-ray diffraction.

None
Date: January 28, 2002
Creator: Zeng, Z.; Natesan, K. & Maroni, V.A.
System: The UNT Digital Library
Applications of Sensitivity Analysis to Uncertainty Quantification in Variably Saturated Flow (open access)

Applications of Sensitivity Analysis to Uncertainty Quantification in Variably Saturated Flow

In this paper, we present results demonstrating the effectiveness of a sensitivity analysis approach to uncertainty quantification of a variably saturated flow model. The basis for our method is a software system which simultaneously solves for solutions of large-scale nonlinear systems of equations and the sensitivity of the solutions to selected parameters. We present test cases showing the effects on the relative uncertainty of pressure due to heterogeneity in the absolute permeability and to differences in parameterizing the Van Genuchten curve soil parameters, {alpha} and n.
Date: January 28, 2002
Creator: Woodward, C; Grant, K E & Maxwell, R
System: The UNT Digital Library
On Attaching a Wire to a Triangulated Surface (open access)

On Attaching a Wire to a Triangulated Surface

There have been many papers that have focused on the attachment of wires to surfaces. The focus of this paper will be on wires connected to arbitrarily shaped surfaces, a body that may be modeled with triangles as described in [1]. The basis function for the wire-to-surface junction is constructed by building the 1/r variation of the surface current near the junction into the surface current. In the following we summarize junction bases as currently used. In the presentation we consider their numerical implementation, examine alternative formulations, and review validation studies that prove the approach is robust with respect to wire orientation and surface geometry at the junction.
Date: January 28, 2002
Creator: Champagne, N J; Johnson, W A & Wilton, D R
System: The UNT Digital Library
8-(Hydroxymethyl)-3,N4-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases (open access)

8-(Hydroxymethyl)-3,N4-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases

None
Date: January 28, 2002
Creator: Singer, B.; Medina, Michael; Zhang, Yanbin; Wang, Zhigang; Guliaev, Anton B. & Hang, Bo
System: The UNT Digital Library
Environmental regulatory approaches for petroleum refineries. (open access)

Environmental regulatory approaches for petroleum refineries.

None
Date: January 28, 2002
Creator: Elcock, D.; Gasper, J. & Moses, D. O.
System: The UNT Digital Library
BioZone Exploting Source-Capability Information for Integrated Access to Multiple Bioinformatics Data Sources (open access)

BioZone Exploting Source-Capability Information for Integrated Access to Multiple Bioinformatics Data Sources

Modern Bioinformatics data sources are widely used by molecular biologists for homology searching and new drug discovery. User-friendly and yet responsive access is one of the most desirable properties for integrated access to the rapidly growing, heterogeneous, and distributed collection of data sources. The increasing volume and diversity of digital information related to bioinformatics (such as genomes, protein sequences, protein structures, etc.) have led to a growing problem that conventional data management systems do not have, namely finding which information sources out of many candidate choices are the most relevant and most accessible to answer a given user query. We refer to this problem as the query routing problem. In this paper we introduce the notation and issues of query routing, and present a practical solution for designing a scalable query routing system based on multi-level progressive pruning strategies. The key idea is to create and maintain source-capability profiles independently, and to provide algorithms that can dynamically discover relevant information sources for a given query through the smart use of source profiles. Compared to the keyword-based indexing techniques adopted in most of the search engines and software, our approach offers fine-granularity of interest matching, thus it is more powerful and …
Date: January 28, 2002
Creator: Liu, Ling; Buttler, David; Paques, Henrique; Pu, Calton & Critchlow, Terence
System: The UNT Digital Library