States

(NLUF user-application of a high-density gas laser target to the physics x-ray lasers and coronal plasmas) (open access)

(NLUF user-application of a high-density gas laser target to the physics x-ray lasers and coronal plasmas)

None
Date: March 13, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Urban Options Solar Greenhouse Project. Semi-annual technical progress report (open access)

Urban Options Solar Greenhouse Project. Semi-annual technical progress report

The design changes and construction of the Urban Options Solar Greenhouse are described. The greenhouse performance and horticultural and educational activities are discussed. (MHR)
Date: March 13, 1980
Creator: Cipparone, L.
Object Type: Report
System: The UNT Digital Library
Steering system for a train of rail-less vehicles (open access)

Steering system for a train of rail-less vehicles

A steering system for use with a multiple vehicle train is disclosed which permits tracking without rails of one vehicle after another. This system is particularly useful for moving conveyor systems into and out of curved paths of room and pillar underground mine installations. The steering system features an elongated steering bar pivotally connected to each of adjacent vehicles at end portions of the bar permitting angular orientation of each vehicle in respect to the steering bar and other vehicles. Each end portion of the steering bar is linked to the near pair of vehicle wheels through wheel yoke pivot arms about king pin type pivots. Movement of the steering bar about its pivotal connection provides proportional turning of the wheels to effect steering and tracking of one vehicle following another in both forward and reverse directions.
Date: March 13, 1981
Creator: Voight, Edward Theodore
Object Type: Patent
System: The UNT Digital Library
THE SUBCRITICAL REACTOR WITH SOURCES (open access)

THE SUBCRITICAL REACTOR WITH SOURCES

The mathematical formulation of the subcritical reactor with extraneous sources is presented in detail. The solutions are presented for a two-group approximation including epithermal fission and the relationship to the usual critical reactor problem is discussed. Application of the equations to an arbitrarily complicated geometry is outlined, and an IBM-7090 program for the solution in a bare cylindrical reactor is described. (auth)
Date: March 13, 1962
Creator: Preskitt, C.A.
Object Type: Report
System: The UNT Digital Library
Receiver for solar-energy collector having improved aperture aspect (open access)

Receiver for solar-energy collector having improved aperture aspect

A secondary concentrator for use in receiver systems for linear focusing primary concentrators is provided with reflector wings at each end. The wings increase the capture of light rays reflected from areas adjacent the rim of a primary concentrator, increasing the apparent aperture size of the receiver as viewed from the rim of the primary concentrator. The length, tilt, and curvature of the wing reflectors can be adjusted to provide a receiver having a desired aperture aspect.
Date: March 13, 1981
Creator: McIntire, W.R.
Object Type: Patent
System: The UNT Digital Library
Molecular biological enhancement of coal biodesulfurization (open access)

Molecular biological enhancement of coal biodesulfurization

The objective of this project is to produce one or more microorganisms capable of the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: (1) clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; (2) return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; (3) transfer this pathway into a fast-growing chemolithotrophic bacterium; (4) conduct a batch-mode optimization/analysis of scale-up variables. By letter of September 3, 1991, from the Project Manager at Department of Energy, Pittsburgh Energy Technology Center, these objectives of this project were redirected toward finding and developing suitable vectors for Thiobacillus strains. All work on bacterial strains from Lehigh University was terminated since they did not contain desulfurization traits represented by the 4S'' pathway.
Date: March 13, 1992
Creator: Litchfield, J. H.; Zupancic, T. J.; Kittle Jr., J. D.; Baker, B.; Palmer, D. T.; Traunero, C. G. et al.
Object Type: Report
System: The UNT Digital Library
Perspectives in the theory of nuclear collective motion (open access)

Perspectives in the theory of nuclear collective motion

This report discusses three different subjects. The first is the development of a generalized version of the VMI (variable moment of inertia) model that ties it to the original form of the IBM (interacting boson model) and provides a possibility of fitting vibrational spectra with generalized vibrational formulas. The second is a suggestion for fitting band crossing calculations of the phenomenological type more completely than has hitherto been done into the framework of the VMI method. The third, which is the most important and far reaching, is the description f a complete mathematical method for the microscopic derivation of the IBM from a conventional shell-model Hamiltonian. In addition to elements already foreseen by previous authors, there is proposed a solution for the most important problem outstanding, not only within the framework of the IBM, but also in all previous work on boson expansion. This is the problem of actually selecting, in a general fashion, the most collective excitations. A criterion is introduced that the subspace constructed from these excitations should possess an average energy that is lower than the rest of the shell model space; the actual implementation of this criterion is explained. 8 tables, 62 references.
Date: March 13, 1980
Creator: Klein, A.
Object Type: Article
System: The UNT Digital Library
System for utilizing shale oil fines. [Patent application] (open access)

System for utilizing shale oil fines. [Patent application]

A system is provided for utilizing fines of carbonaceous materials such as particles or pieces of oil shale of about one-half inch or less diameter which are rejected for use in some conventional or prior surface retorting process, which obtains maximum utilization of the energy content of the fines and which produces a waste which is relatively inert and of a size to facilitate disposal. The system includes a cyclone retort which pyrolyzes the fines in the presence of heated gaseous combustion products, the cyclone retort having a first outlet through which vapors can exit that can be cooled to provide oil, and having a second outlet through which spent shale fines are removed. A burner connected to the spent shale outlet of the cyclone retort, burns the spent shale with air, to provide hot combustion products that are carried back to the cyclone retort to supply gaseous combustion products utilized therein. The burner heats the spent shale to a temperature which forms a molten slag, and the molten slag is removed from the burner into a quencher that suddenly cools the molten slag to form granules that are relatively inert and of a size that is convenient to handle …
Date: March 13, 1981
Creator: Harak, A. E.
Object Type: Patent
System: The UNT Digital Library
Radiological Survey Results for Areas A1 North, A5A, A6, and B2 at the Molycorp Washington Remediation Project, Washington, Pennsylvania (open access)

Radiological Survey Results for Areas A1 North, A5A, A6, and B2 at the Molycorp Washington Remediation Project, Washington, Pennsylvania

Perform radiological surveys of the Molycorp Washington Remediation Project (MWRP) facility in Washington, Pennsylvania
Date: March 13, 2007
Creator: Adams, W. C.
Object Type: Report
System: The UNT Digital Library
Hyperfine Quenching of the 2s2p 3P0 State of Berylliumlike Ions (open access)

Hyperfine Quenching of the 2s2p 3P0 State of Berylliumlike Ions

The hyperfine-induced 2s2p {sup 3}P{sub 0}-2s{sup 2} {sup 1}S{sub 0} transition rate for Be-like {sup 47}Ti{sup 18+} was recently measured in a storage-ring experiment by Schippers et al. [Phys. Rev. Lett. 98, 033001 (2007)]. The measured value of 0.56(3) s{sup -1} is almost 60% larger than the theoretical value of 0.356 s{sup -1} from a multiconfiguration Dirac-Fock calculation by Marques et al. [Phys. Rev. A 47, 929 (1993)]. In this work, we use a large-scale relativistic configuration-interaction method to calculate these hyperfine-induced rates for ions with Z = 6-92. Coherent hyperfine-quenching effects between the 2s2p {sup 1,3}P{sub 1} states are included in a perturbative as well as a radiation damping approach. Contrary to the claims of Marques et al., contributions from the {sup 1}P{sub 1} state are substantial and lead to a hyperfine-induced rate of 0.67 s{sup -1}, in better agreement with, though larger than, the measured value.
Date: March 13, 2008
Creator: Cheng, K T; Chen, M H & Johnson, W R
Object Type: Article
System: The UNT Digital Library
Cleanup Verification Package for the 300 VTS Waste Site (open access)

Cleanup Verification Package for the 300 VTS Waste Site

This cleanup verification package documents completion of remedial action for the 300 Area Vitrification Test Site, also known as the 300 VTS site. The site was used by Pacific Northwest National Laboratory as a field demonstration site for in situ vitrification of soils containing simulated waste.
Date: March 13, 2006
Creator: Mitchell, S. W. Clark and T. H.
Object Type: Report
System: The UNT Digital Library
Nanofiltration of Electrolyte Solutions by Sub-2nm Carbon Nanotube Membranes (open access)

Nanofiltration of Electrolyte Solutions by Sub-2nm Carbon Nanotube Membranes

Both MD simulations and experimental studies have shown that liquid and gas flow through carbon nanotubes with nanometer size diameter is exceptionally fast. For applications in separation technology, selectivity is required together with fast flow. In this work, we use pressure-driven filtration experiments to study ion exclusion in silicon nitride/sub-2-nm CNT composite membranes as a function of solution ionic strength, pH, and ion valence. We show that carbon nanotube membranes exhibit significant ion exclusion at low salt concentration. Our results support a rejection mechanism dominated by electrostatic interactions between fixed membrane charges and mobile ions, while steric and hydrodynamic effects appear to be less important. Comparison with commercial nanofiltration membranes for water softening reveals that our carbon nanotube membranes provides far superior water fluxes for similar ion rejection capabilities.
Date: March 13, 2008
Creator: Fornasiero, F.; Park, H. G.; Holt, J. K.; Stadermann, M.; Kim, S.; In, J. B. et al.
Object Type: Article
System: The UNT Digital Library
Creep Testing Plastic-Bonded Explosives in Uni-axial Compression (open access)

Creep Testing Plastic-Bonded Explosives in Uni-axial Compression

High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavior of each material is related to the type of explosive and to the percentage and type of binder. For any given plastic-bonded explosive, the creep behavior is also dependent on the stress level and test temperature. Experiments were conducted using a 3 x 3 stress-temperature matrix with a temperature range of 24 C to 70 C and with stresses ranging from 250-psi to 780-psi. Analysis of the data has shown that logarithmic curve fits provide an accurate means of quantification and facilitate a long-term predictive capability. This paper will discuss the design of the apparatus, experimental results, and analyses.
Date: March 13, 2008
Creator: Gagliardi, F J & Cunningham, B J
Object Type: Article
System: The UNT Digital Library
A multi-model assessment of pollution transport to the Arctic (open access)

A multi-model assessment of pollution transport to the Arctic

We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using results from a coordinated model intercomparison. These sensitivities to regional emissions (mixing ratio change per unit emission) vary widely across models and species. Intermodel differences are systematic, however, so that the relative importance of different regions is robust. North America contributes the most to Arctic ozone pollution. For aerosols and CO, European emissions dominate at the Arctic surface but East Asian emissions become progressively more important with altitude, and are dominant in the upper troposphere. Sensitivities show strong seasonality: surface sensitivities typically maximize during boreal winter for European and during spring for East Asian and North American emissions. Mid-tropospheric sensitivities, however, nearly always maximize during spring or summer for all regions. Deposition of black carbon (BC) onto Greenland is most sensitive to North American emissions. North America and Europe each contribute {approx}40% of total BC deposition to Greenland, with {approx}20% from East Asia. Elsewhere in the Arctic, both sensitivity and total BC deposition are dominated by European emissions. Model diversity for aerosols is especially large, resulting primarily from differences in aerosol physical and chemical processing …
Date: March 13, 2008
Creator: Shindell, D T; Chin, M; Dentener, F; Doherty, R M; Faluvegi, G; Fiore, A M et al.
Object Type: Article
System: The UNT Digital Library

Quantitative Analyses of the Severity of Attack on Crevice Corrosion Surfaces

None
Date: March 13, 2006
Creator: Hodges, A. J. & Kelly, R. G.
Object Type: Presentation
System: The UNT Digital Library
ESF BLAST DESIGN ANALYSIS (open access)

ESF BLAST DESIGN ANALYSIS

The purpose and objective of this design analysis are to develop controls considered necessary and sufficient to implement the requirements for the controlled drilling and blasting excavation of operations support alcoves and test support alcoves in the Exploratory Studies Facility (ESF). The conclusions reached in this analysis will flow down into a construction specification ensuring controlled drilling and blasting excavation will be performed within the bounds established here.
Date: March 13, 1995
Creator: Fitch, E. F.
Object Type: Report
System: The UNT Digital Library
COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL (open access)

COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL

None
Date: March 13, 2006
Creator: Bocher, F.; Presuel-Moreno, F.; Budiansky, N.D. & Scully, J.R.
Object Type: Article
System: The UNT Digital Library
Regulation of In Situ to Invasive Breast Carcinoma Transition (open access)

Regulation of In Situ to Invasive Breast Carcinoma Transition

The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed the role of myoepithelial cells and fibroblasts in the progression of in situ carcinomas using a xenograft model of human DCIS. Progression to invasion was promoted by fibroblasts, but inhibited by normal myoepithelial cells. The invasive tumor cells from these progressed lesions formed DCIS rather than invasive cancers when re-injected into naive mice. Molecular profiles of myoepithelial and epithelial cells isolated from primary normal and cancerous human breast tissue samples corroborated findings obtained in the xenograft model. These results provide the proof of principle that breast tumor progression could occur in the absence of additional genetic alterations and that tumor growth and progression could be controlled by replacement of normal myoepithelial inhibitory signals.
Date: March 13, 2007
Creator: Hu, Min; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen, Haiyan; Carrasco, Daniel; Richardson, Andrea et al.
Object Type: Article
System: The UNT Digital Library
Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling (open access)

Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling

A carbon-rich black layer, dating to ~;;12.9 ka, has been previously identified at ~;;50 Clovis-age sites across North America and appears contemporaneous with the abrupt onset of Younger Dryas (YD) cooling. The in situ bones of extinct Pleistocene megafauna, along with Clovis tool assemblages, occur below this black layer but not within or above it. Causes for the extinctions, YD cooling, and termination of Clovis culture have long been controversial. In this paper, we provide evidence for an extraterrestrial (ET) impact event at ~;;12.9 ka, which we hypothesize caused abrupt environmentalchanges that contributed to YD cooling, major ecological reorganization, broad-scale extinctions, and rapid human behavioral shifts at the end of the Clovis Period. Clovis-age sites in North American are overlain by a thin, discrete layer with varying peak abundances of (i) magnetic grains with iridium, (ii) magnetic microspherules, (iii) charcoal, (iv) soot, (v) carbon spherules, (vi) glass-like carbon containing nanodiamonds, and (vii) fullerenes with ET helium, all of which are evidence for an ET impact and associated biomass burning at ~;;12.9 ka. This layer also extends throughout at least 15 Carolina Bays, which are unique, elliptical depressions, oriented to the northwest across the Atlantic Coastal Plain. We propose that one …
Date: March 13, 2007
Creator: Firestone, Richard B.; Firestone, R. B.; West, A.; Kennett, J. P.; Becker, L.; Bunch, T. E. et al.
Object Type: Article
System: The UNT Digital Library
Design and Formation of a Large, Tetrahedral, Metal-ligand Cluster Using 1,1'-Binaphthyl Ligands (open access)

Design and Formation of a Large, Tetrahedral, Metal-ligand Cluster Using 1,1'-Binaphthyl Ligands

Many chemists have been fascinated with the development of discrete supramolecular structures that encapsulate guest molecules. These structures can be assembled through covalent or hydrogen bonds, electrostatic or metal-ligand interactions. These host structures have provided valuable insight into the forces involved in small molecule recognition. Our work has focused on the design and study of metal-ligand clusters of varying sizes. The naphthalene [M{sub 4}L{sub 6}]{sup 12-} cluster 1, shown in Figure 1, has demonstrated diastereoselective guest binding and chiral induction properties as well as the ability to catalyze reactions carried out inside the cavity in an enzyme-like manner. However, the size of the cavity (ca. 300-500 {angstrom}{sup 3}) has often limited the scope of substrates for these transformations.
Date: March 13, 2008
Creator: Biros, Shannon M.; Yeh, Robert M. & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
Long-term stability of organic carbon-stimulated chromatereduction in contaminated soils, and its relation to manganese redoxstatus (open access)

Long-term stability of organic carbon-stimulated chromatereduction in contaminated soils, and its relation to manganese redoxstatus

In-situ reduction of toxic Cr(V1) to less hazardous Cr(II1)is becoming a popular strategy for remediating contaminated soils.However, the long term stability of reduced Cr remains to be understood,especially given the common presence of MnfIIIJV) oxides that reoxidizeCr(II1). This 4.6 year laboratory study tracked Cr and Mn redoxtransformations in soils contaminated with Cr(V1) which were then treatedwith different amounts of organic carbon (OC). Changes in Cr and Mnoxidation states within soils were directly and nondestructively measuredusing micro X-ray absorption near edge structure spectroscopy. Chromatereduction was roughly lst-order, and the extent of reduction was enhancedwith higher OC additions. However, significant Cr(||1) reoxidationoccurred in soils exposed to the highest Cr(V1) concentrations (2,560 mgkg"'). Transient Cr(II1) reoxidation up to 420 mg kg1 was measured at 1.1years after OC treatment, followed by further reduction. Chromateconcentrations increased by 220 mg kgm1a t the end of the study (4.6years) in one soil. The causal role that Mn oxidation state had inreoxidizing Cr was supported by trends in Mn K-edge energies. Theseresults provide strong evidence for longterm dependence of soil Croxidation states on balances between OC availability and Mn redoxstatus.
Date: March 13, 2007
Creator: Tokunaga, Tetsu K.; Wan, Jiamin; Lanzirotti, Antonio; Sutton,Steve R.; Newville, Matthew & Rao, William
Object Type: Article
System: The UNT Digital Library
THE HYDROLYSIS AND OXIDATION BEHAVIOR OF LITHIUM BOROHYDRIDE AND MAGNESIUM HYDRIDE DETERMINED BY CALORIMETRY (open access)

THE HYDROLYSIS AND OXIDATION BEHAVIOR OF LITHIUM BOROHYDRIDE AND MAGNESIUM HYDRIDE DETERMINED BY CALORIMETRY

Lithium borohydride, magnesium hydride and the 2:1 'destabilized' ball milled mixtures (2LiBH{sub 4}:MgH{sub 2}) underwent liquid phase hydrolysis, gas phase hydrolysis and air oxidation reactions monitored by isothermal calorimetry. The experimentally determined heats of reaction and resulting products were compared with those theoretically predicted using thermodynamic databases. Results showed a discrepancy between the predicted and observed hydrolysis and oxidation products due to both kinetic limitations and to the significant amorphous character of observed reaction products. Gas phase and liquid phase hydrolysis were the dominant reactions in 2LiBH{sub 4}:MgH{sub 2} with approximately the same total energy release and reaction products; liquid phase hydrolysis displayed the maximum heat flow for likely environmental exposure with a peak energy release of 6 (mW/mg).
Date: March 13, 2008
Creator: Brinkman, K; Donald Anton, D; Joshua Gray, J & Bruce Hardy, B
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for 100-F-38 Stained Soil Site, Waste Site Reclassification Form 2004-093 (open access)

Remaining Sites Verification Package for 100-F-38 Stained Soil Site, Waste Site Reclassification Form 2004-093

The 100-F-38 Stained Soil site was an area of yellow stained soil that was discoverd while excavating a trench for the placement of electrical conduit. The 100-F-38 Stained Soil site meets the remedial action objectives specified in the Remaining Sites ROD. The results of verification sampling show demonstrate that residual contaminant concentrations support future unrestricted land uses that can be represented by a rural-residential scenario. The results also show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils and the contaminant concentrations remaining in the soil are protective of groundwater and the Columbia River.
Date: March 13, 2006
Creator: Carlson, R. A.
Object Type: Report
System: The UNT Digital Library
Rupture-safe pressure transducers (open access)

Rupture-safe pressure transducers

The design, fabrication and testing of a rupture-safe transducer for measuring gas pressures in a manned-area field environment are described. (LCL)
Date: March 13, 1979
Creator: Holten, D.C.
Object Type: Article
System: The UNT Digital Library