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Distributed drift chamber design for rare particle detection in relativistic heavy ion collisions (open access)

Distributed drift chamber design for rare particle detection in relativistic heavy ion collisions

This report describes a multi-plane drift chamber that was designed and constructed to function as a topological detector for the BNL AGSE896 rare particle experiment. The chamber was optimized for good spatial resolution, two track separation, and a high uniform efficiency while operating in a 1.6 Tesla magnetic field and subjected to long term exposure from a 11.6 GeV/nucleon beam of 10**6 Au ions per second.
Date: October 2, 2001
Creator: Bellwied, R.; Bennett, M. J.; Bernardo, V.; Caines, H.; Christie, W.; Costa, S. et al.
Object Type: Article
System: The UNT Digital Library
The Ranger (San Antonio, Tex.), Vol. 77, No. 9, Ed. 1 Friday, November 9, 2001 (open access)

The Ranger (San Antonio, Tex.), Vol. 77, No. 9, Ed. 1 Friday, November 9, 2001

Weekly student newspaper from San Antonio College in San Antonio, Texas that includes campus news along with advertising.
Date: November 9, 2001
Creator: San Antonio College
Object Type: Newspaper
System: The Portal to Texas History
Reduction in Defect Content of ODS Alloys (open access)

Reduction in Defect Content of ODS Alloys

The work detailed within this report is a continuation of earlier work carried out under contract number 1DX-SY382V. The earlier work comprises a literature review of the sources and types of defects found principally in Fe-based ODS alloys as well as experimental work designed to identify defects in the prototype ODS-Fe{sub 3}Al alloy, deduce their origins and to recommend methods of defect reduction. The present work is an extension of the experimental work already reported and concentrates on means of reduction of defects already identified rather than the search for new defect types. This report also includes results gathered during powder separation trials, conducted by the University of Groningen, Netherlands and coordinated by the University of Liverpool, involving the separation of different metallic powders in terms of their differing densities. The scope and objectives of the present work were laid out in the technical proposal ''Reduction in Defect Content in ODS Alloys-III''. All the work proposed in the ''Statement of Work'' section of the technical proposal has been carried out and all work extra to the ''Statement of Work'' falls within the context of an ODS-Fe{sub 3}Al alloy of improved overall quality and potential creep performance in the consolidated form. …
Date: May 15, 2001
Creator: Ritherdon, J.
Object Type: Report
System: The UNT Digital Library
The Hexagon, Volume 92, Number 2, Summer 2001 (open access)

The Hexagon, Volume 92, Number 2, Summer 2001

Quarterly publication of the Alpha Chi Sigma chemistry fraternity containing articles related to chemistry research and the activities of the organization, including local chapters and groups.
Date: Summer 2001
Creator: Alpha Chi Sigma
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
The Ranger (San Antonio, Tex.), Vol. 77, No. 6, Ed. 1 Friday, October 19, 2001 (open access)

The Ranger (San Antonio, Tex.), Vol. 77, No. 6, Ed. 1 Friday, October 19, 2001

Weekly student newspaper from San Antonio College in San Antonio, Texas that includes campus news along with advertising.
Date: October 19, 2001
Creator: San Antonio College
Object Type: Newspaper
System: The Portal to Texas History
REPRESENTING AEROSOL DYNAMICS AND PROPERTIES IN CHEMICAL TRANSPORT MODELS BY THE METHOD OF MOMENTS. (open access)

REPRESENTING AEROSOL DYNAMICS AND PROPERTIES IN CHEMICAL TRANSPORT MODELS BY THE METHOD OF MOMENTS.

Atmospheric aerosols, suspensions of solid or liquid particles, are an important multi-phase system. Aerosols scatter and absorb shortwave (solar) radiation, affecting climate (Charlson et al., 1992; Schwartz, 1996) and visibility; nucleate cloud droplet formation, modifying the reflectivity of clouds (Twomey et al., 1984; Schwartz and Slingo, 1996) as well as contributing to composition of cloudwater and to wet deposition (Seinfeld and Pandis, 1998); and affect human health through inhalation (NRC, 1998). Existing and prospective air quality regulations impose standards on concentrations of atmospheric aerosols to protect human health and welfare (EPA, 1998). Chemical transport and transformation models representing the loading and geographical distribution of aerosols and precursor gases are needed to permit development of effective and efficient strategies for meeting air quality standards, and for examining aerosol effects on climate retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes depend on their size distribution: light scattering, cloud nucleating properties, dry deposition, and penetration into airways of lungs. The evolution of the mass loading itself depends on particle size because of the size dependence of growth and removal processes. For these reasons it is increasingly recognized that chemical transport and transformation models must represent not just the mass …
Date: April 2001
Creator: Schwartz, S. E.; McGraw, R.; Benkovitz, C. M. & Wright, D. L.
Object Type: Article
System: The UNT Digital Library
Representing Aerosol Dynamics and Properties in Chemical Transport Models by the Method of Moments (open access)

Representing Aerosol Dynamics and Properties in Chemical Transport Models by the Method of Moments

Atmospheric aerosols, suspensions of solid or liquid particles, are an important multi-phase system. Aerosols scatter and absorb shortwave (solar) radiation, affecting climate (Charlson et al., 1992; Schwartz, 1996) and visibility; nucleate cloud droplet formation, modifying the reflectivity of clouds (Twomey et al., 1984; Schwartz and Slingo, 1996) as well as contributing to composition of cloudwater and to wet deposition (Seinfeld and Pandis, 1998); and affect human health through inhalation (NRC, 1998). Existing and prospective air quality regulations impose standards on concentrations of atmospheric aerosols to protect human health and welfare (EPA, 1998). Chemical transport and transformation models representing the loading and geographical distribution of aerosols and precursor gases are needed to permit development of effective and efficient strategies for meeting air quality standards, and for examining aerosol effects on climate retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes depend on their size distribution: light scattering, cloud nucleating properties, dry deposition, and penetration into airways of lungs. The evolution of the mass loading itself depends on particle size because of the size dependence of growth and removal processes. For these reasons it is increasingly recognized that chemical transport and transformation models must represent not just the mass …
Date: April 1, 2001
Creator: Schwartz, S. E.; McGraw, R.; Benkovitz, C. M. & Wright, D. L.
Object Type: Article
System: The UNT Digital Library
The mitochondrial genome of the sipunculid Phascolopsis gouldii supports its association with Annelida rather than Mollusca (open access)

The mitochondrial genome of the sipunculid Phascolopsis gouldii supports its association with Annelida rather than Mollusca

We have determined the sequence of about half (7470 nts) of the mitochondrial genome of the sipunculid Phascolopsis gouldii, the first representative of this phylum to be so studied. All of the 19 identified genes are transcribed from the same DNA strand. The arrangement of these genes is remarkably similar to that of the oligochaete annelid Lumbricus terrestris. Comparison of both the inferred amino acid sequences and the gene arrangements of a variety of diverse metazoan taxa reveals that the phylum Sipuncula is more closely related to Annelida than to Mollusca. This requires reinterpretation of the homology of several embryological features and of patterns of animal body plan evolution.
Date: September 1, 2001
Creator: Boore, Jeffrey L. & Staton, Joseph
Object Type: Article
System: The UNT Digital Library
Laser ablation in analytical chemistry - A review (open access)

Laser ablation in analytical chemistry - A review

Laser ablation is becoming a dominant technology for direct solid sampling in analytical chemistry. Laser ablation refers to the process in which an intense burst of energy delivered by a short laser pulse is used to sample (remove a portion of) a material. The advantages of laser ablation chemical analysis include direct characterization of solids, no chemical procedures for dissolution, reduced risk of contamination or sample loss, analysis of very small samples not separable for solution analysis, and determination of spatial distributions of elemental composition. This review describes recent research to understand and utilize laser ablation for direct solid sampling, with emphasis on sample introduction to an inductively coupled plasma (ICP). Current research related to contemporary experimental systems, calibration and optimization, and fractionation is discussed, with a summary of applications in several areas.
Date: October 10, 2001
Creator: Russo, Richard E.; Mao, Xianglei; Liu, Haichen; Gonzalez, Jhanis & Mao, Samuel S.
Object Type: Article
System: The UNT Digital Library
Collin Chronicles, Volume 21, Number 1, 2000/2001 (open access)

Collin Chronicles, Volume 21, Number 1, 2000/2001

Quarterly publication containing "notification of upcoming events, timely material from local societies, general research information, material availability from area libraries, spotlighting members, and other news."
Date: 2001
Creator: Collin County Genealogical Society
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
High Temperature Materials Laboratory Thirteenth Annual Report: October 1999 Through September 2000 (open access)

High Temperature Materials Laboratory Thirteenth Annual Report: October 1999 Through September 2000

The High Temperature Materials Laboratory (HTML) User Program continued to work with industrial, academic, and governmental users this year, accepting 86 new projects and developing 50 new user agreements. The table on the following page presents the breakdown of these statistics. The figure on page 2 depicts the continued growth in user agreements and user projects. You may note that our total number of proposals is nearing 1000, and we expect to achieve this number in our first proposal review meeting of FY 2001. The large number of new agreements bodes well for the future. A list of proposals to the HTML follows this section; at the end of the report, we present a list of agreements between HTML and universities and industries, broken down by state. Program highlights this year included several outstanding user projects (some of which are discussed in later sections), the annual meeting of the HTML Programs Senior Advisory Committee, the completion of a formal Multiyear Program Plan (MYPP), and finalization of a purchase agreement with JEOL for a new-generation electron microscope.
Date: November 7, 2001
Creator: Pasto, AE
Object Type: Report
System: The UNT Digital Library
Complete Sequence of the mitochondrial genome of the tapeworm Hymenolepis diminuta: Gene arrangements indicate that platyhelminths are eutrochozoans (open access)

Complete Sequence of the mitochondrial genome of the tapeworm Hymenolepis diminuta: Gene arrangements indicate that platyhelminths are eutrochozoans

Using ''long-PCR'' we have amplified in overlapping fragments the complete mitochondrial genome of the tapeworm Hymenolepis diminuta (Platyhelminthes: Cestoda) and determined its 13,900 nucleotide sequence. The gene content is the same as that typically found for animal mitochondrial DNA (mtDNA) except that atp8 appears to be lacking, a condition found previously for several other animals. Despite the small size of this mtDNA, there are two large non-coding regions, one of which contains 13 repeats of a 31 nucleotide sequence and a potential stem-loop structure of 25 base pairs with an 11-member loop. Large potential secondary structures are identified also for the non-coding regions of two other cestode mtDNAs. Comparison of the mitochondrial gene arrangement of H. diminuta with those previously published supports a phylogenetic position of flatworms as members of the Eutrochozoa, rather than being basal to either a clade of protostomes or a clade of coelomates.
Date: January 1, 2001
Creator: von Nickisch-Rosenegk, Markus; Brown, Wesley M. & Boore, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
The complete mitochondrial genome of Articulate Brachiopod Terebratal ia transversa (open access)

The complete mitochondrial genome of Articulate Brachiopod Terebratal ia transversa

We have sequenced the complete mitochondrial DNA (mtDNA) of the articulate brachiopod Terebratalia transversa. The circular genome is 14,291 bp in size, relatively small compared to other published metazoan mtDNAs. The 37 genes commonly found in animal mtDNA are present; the size decrease is due to the truncation of several tRNA, rRNA, and protein genes, to some nucleotide overlaps, and to a paucity of non-coding nucleotides. Although the gene arrangement differs radically from those reported for other metazoans, some gene junctions are shared with two other articulate brachiopods, Laqueus rubellus and Terebratulina retusa. All genes in the T. transversa mtDNA, unlike those in most metazoan mtDNAs reported, are encoded by the same strand. The A+T content (59.1 percent) is low for a metazoan mtDNA, and there is a high propensity for homopolymer runs and a strong base-compositional strand bias. The coding strand is quite G+T-rich, a skew that is shared by the confamilial (laqueid) specie s L. rubellus, but opposite to that found in T. retusa, a cancellothyridid. These compositional skews are strongly reflected in the codon usage patterns and the amino acid compositions of the mitochondrial proteins, with markedly different usage observed between T. retusa and the two laqueids. …
Date: July 1, 2001
Creator: Helfenbein, Kevin G.; Brown, Wesley M. & Boore, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
The Ranger (San Antonio, Tex.), Vol. 77, No. 10, Ed. 1 Friday, November 16, 2001 (open access)

The Ranger (San Antonio, Tex.), Vol. 77, No. 10, Ed. 1 Friday, November 16, 2001

Weekly student newspaper from San Antonio College in San Antonio, Texas that includes campus news along with advertising.
Date: November 16, 2001
Creator: San Antonio College
Object Type: Newspaper
System: The Portal to Texas History
German Pioneers on the American Frontier: the Wagners in Texas and Illinois (open access)

German Pioneers on the American Frontier: the Wagners in Texas and Illinois

A case study of two brothers, Julius and Wilhelm Wagner, who immigrated to the United States from Baden, Germany. Julius immigrated as part of an early communist group, the "Darmstädters" or "Forty," who established the utopian settlement of Bettina in 1847. His anti-slavery beliefs forced Julius to Mexico during the Civil War, but he returned to Texas after the war. His older brother Wilhelm fled Germany in 1851 as a result of his liberal political beliefs and settled in Texas. He founded a German-language newspaper when he moved to Freeport, Illinois.
Date: 2001
Creator: Reichstein, Andreas V.
Object Type: Book
System: The UNT Digital Library
The Design-to-Analysis Process at Sandia National Laboratories Observations and Recommendations (open access)

The Design-to-Analysis Process at Sandia National Laboratories Observations and Recommendations

The efficiency of the design-to-analysis process for translating solid-model-based design data to computational analysis model data plays a central role in the application of computational analysis to engineering design and certification. A review of the literature from within Sandia as well as from industry shows that the design-to-analysis process involves a number of complex organizational and technological issues. This study focuses on the design-to-analysis process from a business process standpoint and is intended to generate discussion regarding this important issue. Observations obtained from Sandia staff member and management interviews suggest that the current Sandia design-to-analysis process is not mature and that this cross-organizational issue requires committed high-level ownership. A key recommendation of the study is that additional resources should be provided to the computer aided design organizations to support design-to-analysis. A robust community of practice is also needed to continuously improve the design-to-analysis process and to provide a corporate perspective.
Date: August 1, 2001
Creator: Burns, Shawn P.; Harrison, Randy J. & Dobranich, Dean
Object Type: Report
System: The UNT Digital Library
An NMR study of 2-ethyl-1-butyllithium and of 2-ethyl-1-butyllithium/lithium 2-ethyl-1-butoxide mixed aggregates (open access)

An NMR study of 2-ethyl-1-butyllithium and of 2-ethyl-1-butyllithium/lithium 2-ethyl-1-butoxide mixed aggregates

A 1H, 13C, and 6Li NMR study of 2-ethyl-1-butyllithium indicated that 2-ethyl-1-butyllithium exists only as a hexameric aggregate over the entire temperature range of 25 to - 92.1 ° C in cyclopentane. Reacting 2-ethyl-1-butyllithium with 2-ethyl-1-butanol resulted in alkyllithium/lithium alkoxide mixed aggregates, apparently of the form Ra(RO)bLia+b. A multinuclear, variable temperature NMR study of samples with O:Li ratios of 0.2 and 0.4 showed, in addition to the alkyllithium, the formation of four mixed aggregates, one of them probably an octamer. Higher O:Li ratio samples showed the formation of several other mixed aggregates. Mixing 2-ethyl-1-butyllithium with independently prepared lithium 2-ethyl-1-butoxide formed the same mixed aggregates formed by in situ synthesis of lithium alkoxide. Lithium 2-ethyl-1-butoxide also exists as aggregates in cyclopentane.
Date: May 2001
Creator: Ferreira, Aluisio V. C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Strange Dibaryons in Neutron Stars and in Heavy-Ion Collisons. (open access)

Strange Dibaryons in Neutron Stars and in Heavy-Ion Collisons.

The formation of dibaryons with strangeness are discussed for the interior of neutron stars and for central relativistic heavy-ion collisions. We derive limits for the properties of H-dibaryons from pulsar data. Signals for the formation of possible bound states with hyperons at BNL's Relativistic Heavy-Ion Collider (RHIC) are investigated by studying their weak decay patterns and production rates.
Date: April 25, 2001
Creator: Schaffner-Bielich, J.
Object Type: Article
System: The UNT Digital Library
Optical emission spectra of a copper plasma produced by a metal vapor vacuum arc source (open access)

Optical emission spectra of a copper plasma produced by a metal vapor vacuum arc source

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Date: March 1, 2001
Creator: Yotsombat, B.; Davydov, S.; Poolcharuansin, P.; Vilaithong, T. & Brown, I.G.
Object Type: Article
System: The UNT Digital Library
International Conflict and Property Rights: Fifth Amendment "Takings" Issues (open access)

International Conflict and Property Rights: Fifth Amendment "Takings" Issues

This report discusses the international conflict and property rights. After the terrorist attack on the World Trade Center and Pentagon has raised the possibility of responses by the United States that impinge on private property, and, in turn, the possibility of claims under the Fifth Amendment Takings Clause.
Date: December 5, 2001
Creator: Meltz, Robert
Object Type: Report
System: The UNT Digital Library
Structural Modifications in Fused Silica Due to Laser Damage Induced Shock Compression (open access)

Structural Modifications in Fused Silica Due to Laser Damage Induced Shock Compression

High power laser pulses can produce damage in high quality fused silica optics that can lead to its eventual obscuration and failure. Current models suggest the initiation of a plasma detonation due to absorbing initiators and defects, leading to the formation of shock waves. Recent experiments have found a densified layer at the bottom of damage sites, as evidence of the laser-damage model. We have studied the propagation of shock waves through fused silica using molecular dynamics. These simulations show drastic modifications in the structure and topology of the network, in agreement with experimental observations.
Date: December 5, 2001
Creator: Kubota, A; Davila, L; Caturla, M J; Stolken, J S; Sadigh, B; Quong, A et al.
Object Type: Article
System: The UNT Digital Library
Experimental analysis of high-resolution soft x-ray microscopy (open access)

Experimental analysis of high-resolution soft x-ray microscopy

The soft x-ray, full-field microscope XM-1 at Lawrence Berkeley National Laboratory's (LBNL) Advanced Light Source has already demonstrated its capability to resolve 25-nm features. This was accomplished using a micro zone plate (MZP) with an outer zone width of 25 nm. Limited by the aspect ratio of the resist used in the fabrication, the gold-plating thickness of that zone plate is around 40 nm. However, some applications, in particular, biological imaging, prefer improved efficiency, which can be achieved by high-aspect-ratio zone plates. We accomplish this by using a bilayer-resist process in the zone plate fabrication. As our first attempt, a 40-nm-outer-zone-width MZP with a nickel-plating thickness of 150 nm (aspect ratio of 4:1) was successfully fabricated. Relative to the 25-nm MZP, this zone plate is ten times more efficient. Using this high-efficiency MZP, a line test pattern with half period of 30 nm is resolved by the microscope at photon energy of 500 eV. Furthermore, with a new multilayer mirror, the XM-1 can now perform imaging up to 1.8 keV. An image of a line test pattern with half period of 40 nm has a measured modulation of 90%. The image was taken at 1.77 keV with the high-efficiency MZP …
Date: September 6, 2001
Creator: Chao, Weilun; Anderson, Erik H.; Denbeaux, Gregory; Harteneck, Bruce; Pearson, Angelic L.; Olynick, Deirdre et al.
Object Type: Article
System: The UNT Digital Library
The Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Volume XVII : Effects of Ocean Covariates and Release Timing on First Ocean-Year Survival of Fall Chinook Salmon from Oregon and Washington Coastal Hatcheries. (open access)

The Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Volume XVII : Effects of Ocean Covariates and Release Timing on First Ocean-Year Survival of Fall Chinook Salmon from Oregon and Washington Coastal Hatcheries.

Effects of oceanographic conditions, as well as effects of release-timing and release-size, on first ocean-year survival of subyearling fall chinook salmon were investigated by analyzing CWT release and recovery data from Oregon and Washington coastal hatcheries. Age-class strength was estimated using a multinomial probability likelihood which estimated first-year survival as a proportional hazards regression against ocean and release covariates. Weight-at-release and release-month were found to significantly effect first year survival (p < 0.05) and ocean effects were therefore estimated after adjusting for weight-at-release. Negative survival trend was modeled for sea surface temperature (SST) during 11 months of the year over the study period (1970-1992). Statistically significant negative survival trends (p < 0.05) were found for SST during April, June, November and December. Strong pairwise correlations (r > 0.6) between SST in April/June, April/November and April/December suggest the significant relationships were due to one underlying process. At higher latitudes (45{sup o} and 48{sup o}N), summer upwelling (June-August) showed positive survival trend with survival and fall (September-November) downwelling showed positive trend with survival, indicating early fall transition improved survival. At 45{sup o} and 48{sup o}, during spring, alternating survival trends with upwelling were observed between March and May, with negative trend occurring …
Date: May 1, 2001
Creator: Burgess, Caitlin & Skalski, John R.
Object Type: Report
System: The UNT Digital Library
College of Music program book 2000-2001 Ensemble Performances Vol. 2 (open access)

College of Music program book 2000-2001 Ensemble Performances Vol. 2

Ensemble performances program book from the 2000-2001 school year at the University of North Texas College of Music.
Date: 2001
Creator: University of North Texas. College of Music.
Object Type: Book
System: The UNT Digital Library