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Reduction of Tropical Cloudiness by Soot (open access)

Reduction of Tropical Cloudiness by Soot

Measurements and models show that enhanced aerosol concentrations can augment cloud albedo not only by increasing total droplet cross-sectional area, but also by reducing precipitation and thereby increasing cloud water content and cloud coverage. Aerosol pollution is expected to exert a net cooling influence on the global climate through these conventional mechanisms. Here we demonstrate an opposite mechanism through which aerosols can reduce cloud cover and thus significantly offset aerosol-induced radiative cooling at the top of the atmosphere on a regional scale. In model simulations the daytime clearing of trade cumulus is hastened and intensified by solar heating in dark haze (as found over much of the northern Indian Ocean during the northeast monsoon).
Date: May 8, 2000
Creator: Ackerman, A. S.; Toon, O. B.; Stevens, D. E.; Heymsfield, A. J. & Ramanathan, V.
Object Type: Report
System: The UNT Digital Library
Qcd physics: study of jet shapes in inclusive jet production in ppbar collisions at sqrt s = 1.96 tev (open access)

Qcd physics: study of jet shapes in inclusive jet production in ppbar collisions at sqrt s = 1.96 tev

We present a search for excited and exotic electrons (e*) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the CDF II detector. No signal above standard model expectation is seen for associated ee* production. We discuss the e* sensitivity in the parameter space of the excited electron mass M{sub e*} and the compositeness energy scale {Lambda}. In the contact interaction model, we exclude 132 GeV/c{sup 2} < M{sub e*} < 879 GeV/c{sup 2} for {Lambda} = M{sub e*} at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c{sup 2} < M{sub e*} < 430 GeV/c{sup 2} at 95% C.L. for the phenomenological coupling f/{Lambda} {approx} 10{sup -2} GeV{sup -1}.
Date: May 8, 2005
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Amorphous Diamond Flat Panel Displays - Final Report of ER-LTR CRADA project with SI Diamond Technology (open access)

Amorphous Diamond Flat Panel Displays - Final Report of ER-LTR CRADA project with SI Diamond Technology

The objective of this project was to determine why diamond-based films are unusually efficient electron emitters (field emission cathodes) at room temperature. Efficient cathodes based on diamond are being developed by SI Diamond Technology (SIDT) as components for bright, sunlight-readable, flat panel displays. When the project started, it was known that only a small fraction (<1%) of the cathode area is active in electron emission and that the emission sites themselves are sub-micron in size. The critical challenge of this project was to develop new microcharacterization methods capable of examining known emission sites. The research team used a combination of cathode emission imaging (developed at SIDT), micro-Raman spectroscopy (LBNL), and electron microscopy and spectroscopy (National Center for Electron Microscopy, LBNL) to examine the properties of known emission sites. The most significant accomplishment of the project was the development at LBNL of a very high resolution scanning probe that, for the first time, measured simultaneously the topography and electrical characteristics of single emission sites. The increased understanding of the emission mechanism helped SIDT to develop a new cathode material,''nano-diamond,'' which they have incorporated into their Field Emission Picture Element (FEPix) product. SIDT is developing large-format flat panel displays based on these …
Date: May 8, 1998
Creator: Ager, Joel W., III
Object Type: Report
System: The UNT Digital Library
Multi-Model Combination Techniques for Hydrological Forecasting: Application to Distributed Model Intercomparison Project Results (open access)

Multi-Model Combination Techniques for Hydrological Forecasting: Application to Distributed Model Intercomparison Project Results

This paper examines several multi-model combination techniques: the Simple Multimodel Average (SMA), the Multi-Model Super Ensemble (MMSE), Modified Multi-Model Super Ensemble (M3SE) and the Weighted Average Method (WAM). These model combination techniques were evaluated using the results from the Distributed Model Intercomparison Project (DMIP), an international project sponsored by the National Weather Service (NWS) Office of Hydrologic Development (OHD). All of the multi-model combination results were obtained using uncalibrated DMIP model outputs and were compared against the best uncalibrated as well as the best calibrated individual model results. The purpose of this study is to understand how different combination techniques affect the skill levels of the multi-model predictions. This study revealed that the multi-model predictions obtained from uncalibrated single model predictions are generally better than any single member model predictions, even the best calibrated single model predictions. Furthermore, more sophisticated multi-model combination techniques that incorporated bias correction steps work better than simple multi-model average predictions or multi-model predictions without bias correction.
Date: May 8, 2006
Creator: Ajami, N.; Duan, Q.; Gao, X. & Sorooshian, S.
Object Type: Article
System: The UNT Digital Library
Gravitational microlensing searches and results (open access)

Gravitational microlensing searches and results

Baryonic matter, in the form of Machos (MAssive Compact Halo Objects), might be a significant constituent of the dark matter that dominates the Milky Way. This article describes how surveys for Machos exploit the gravitational microlens magnification of extragalactic stars. The experimental searches for this effect monitor millions of stars, in some cases every night, looking for magnification events. The early results of these surveys indicate that Machos make up a significant fraction of the dark matter in the Milky Way, and that these objects have stellar masses. Truly substellar objects do not contribute much to the total. Additionally, the relatively high event rate towards the Galactic bulge seems to require that the bulge be elongated, and massive.
Date: May 8, 1997
Creator: Alcock, C.
Object Type: Article
System: The UNT Digital Library
Membership of the 108th Congress: A Profile (open access)

Membership of the 108th Congress: A Profile

None
Date: May 8, 2003
Creator: Amer, Mildred L.
Object Type: Report
System: The UNT Digital Library
Demonstration of the Robotic Gamma Locating and Isotopic Identification Device (open access)

Demonstration of the Robotic Gamma Locating and Isotopic Identification Device

The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in decontaminating and decommissioning nuclear facilities. To this end, the Deactivation and Decommissioning Focus Area of DOE's Office of Science and Technology sponsors Large-Scale Demonstration and Deployment Projects (LSDDP) to test new technologies. As part of these projects, developers and vendors showcase new products designed to decrease health and safety risks to personnel and the environment, increase productivity, and lower costs. As part of the FY 2000 and 2001 LSDDP, the Idaho National Engineering and Environmental Laboratory (INEEL) collaborated with the Russian Research and Development Institute of Construction Technology (NIKIMT). This collaboration resulted in the development of the Robotic Gamma Locating and Isotopic Identification Device (RGL and IID) which integrated DOE Robotics Crosscutting (Rbx) technology with NIKIMT Russian gamma locating and isotopic identification technology. This paper will discuss the technologies involved in this integration and results from the demonstration including reduction of personnel exposure, increase in productivity, and reduced risk.
Date: May 8, 2002
Creator: Anderson, M. O.; Conner, C. C.; Daniel, V. E.; McKay, M. D. & Yancey, N. A.
Object Type: Article
System: The UNT Digital Library
Folding Crate (open access)

Folding Crate

Patent for folding crate. Illustration included.
Date: May 8, 1906
Creator: Anderson, Oliver Lacy
Object Type: Patent
System: The Portal to Texas History
The Influence of Isotopic Composition on the Maximum in the Cosmic Ray Energy Spectra (open access)

The Influence of Isotopic Composition on the Maximum in the Cosmic Ray Energy Spectra

"The previously found maximum in the cosmic radiation energy spectrum is discussed, and the possibility that it arises in part from a misinterpretation of the data due to oversimplifying assumptions about the composition of the beam is examined. The importance that lack of recognition of isotopic composition may have is pointed out, and it is clear that this importance is strongly dependent on the measurements made and on the cut-off rigidity."
Date: May 8, 1961
Creator: Appa Rao, M.V.K. &
Object Type: Report
System: The UNT Digital Library
Strain dependence of the Mn anisotropy in ferromagnetic semiconductors observed by x-ray magnetic circular dichroism (open access)

Strain dependence of the Mn anisotropy in ferromagnetic semiconductors observed by x-ray magnetic circular dichroism

None
Date: May 8, 2007
Creator: Arenholz, Elke; Edmonds, K.W.; van der Laan, G.; Farley, N.R.S.; Arenholz, E.; Campion, R.P. et al.
Object Type: Article
System: The UNT Digital Library
Lattice-matched HfN buffer layers for epitaxy of GaN on Si (open access)

Lattice-matched HfN buffer layers for epitaxy of GaN on Si

Gallium nitride is grown by plasma-assisted molecular-beam epitaxy on (111) and (001) silicon substrates using sputter-deposited hafnium nitride buffer layers. Wurtzite GaN epitaxial layers are obtained on both the (111) and (001) HfN/Si surfaces, with crack-free thickness up to 1.2 (mu)m. Initial results for GaN grown on the (111) surface show a photoluminescence peak width of 17 meV at 11 K, and an asymmetric x-ray rocking curve width of 20 arcmin. Wurtzite GaN on HfN/Si(001) shows reduced structural quality and peculiar low-temperature luminescence features. However, growth on the (001) surface results in nearly stress-free films, suggesting that much thicker crack-free layers could be obtained.
Date: May 8, 2002
Creator: Armitage, Robert; Yang, Qing; Feick, Henning; Gebauer, Joerg; Weber, Eicke R.; Shinkai, Satoko et al.
Object Type: Article
System: The UNT Digital Library
Summary for Policy Makers: Intergovernmental Panel on Climate Change Special Report Renewable Energy Sources (SRREN) (open access)

Summary for Policy Makers: Intergovernmental Panel on Climate Change Special Report Renewable Energy Sources (SRREN)

The Working Group III Special Report on Renewable Energy Sources and Climate Change Mitigation (SRREN) presents an assessment of the literature on the scientific, technological, environmental, economic and social aspects of the contribution of six renewable energy (RE) sources to the mitigation of climate change. It is intended to provide policy relevant information to governments, intergovernmental processes and other interested parties. This Summary for Policymakers provides an overview of the SRREN, summarizing the essential findings. The SRREN consists of 11 chapters. Chapter 1 sets the context for RE and climate change; Chapters 2 through 7 provide information on six RE technologies, and Chapters 8 through 11 address integrative issues.
Date: May 8, 2011
Creator: Arvizu, Dan; Bruckner, Thomas; Christensen, John; Devernay, Jean-Michel; Faaij , Andre; Fischedick, Manfred et al.
Object Type: Article
System: The UNT Digital Library
Tongue-Support for Vehicles. (open access)

Tongue-Support for Vehicles.

Patent for a tongue-support for the tongues of vehicles that "provide an exceedingly simple and effective catch or holder for holding the support up against the under side of the tongue" (lines 18-21), including illustration and instructions
Date: May 8, 1900
Creator: Ashby, William H.
Object Type: Patent
System: The Portal to Texas History
Solid State Electron Transfer via Bacterial Nanowires: Contributions Toward a Mechanistic Understanding of Geophysical Response of Biostimulated Subsurface (open access)

Solid State Electron Transfer via Bacterial Nanowires: Contributions Toward a Mechanistic Understanding of Geophysical Response of Biostimulated Subsurface

The degradation of organic matter by microorganisms provides a source of electrical potential or so-called 'self potential' (SP) that can be measured by using a voltmeter. During this process electrons are being produced as a waste-product and bacterial cells have to dispose of these to allow for the complete biodegradation of organic matter. Especially in anaerobic microbial communities, exo-cellular electron transfer is the most important driving force behind this process and organisms have developed different, but also similar, ways to transfer electrons to other microorganisms. Recently, it has been postulated that direct electron transfer from cell-to-cell is actually done by 'hard-wired' microorganisms. This shuttling of electrons is most likely done by certain c-type cytochromes that form the functional part of electrically conductive nanowires. In this study we investigated if nanowires can explain the geoelectrical (self potential and spectral induced polarization) signals observed at some biostimulated environments such as DOE sites. The objectives of our project are to: (1) investigate any temporal changes in the geophysical signatures (Self Potential (SP) and Induced Polarization (IP)) associated with nanowires of the bacterium Shewanella oneidensis MR-1, wild type and mtrc/omcA deletion mutant, (2) demonstrate that mutant strains of bacteria that produce nonconductive nanowires do …
Date: May 8, 2012
Creator: Atekwana, Estella
Object Type: Report
System: The UNT Digital Library
Measurement of the Nickel/Nickel Oxide Phase Transition in High Temperature Hydrogenated Water Using the Contact Electric Resistance (CER) Technique (open access)

Measurement of the Nickel/Nickel Oxide Phase Transition in High Temperature Hydrogenated Water Using the Contact Electric Resistance (CER) Technique

Prior studies of Alloy 600 and Alloy X-750 have shown the existence of a maximum in stress corrosion cracking (SCC) susceptibility in high temperature water (e.g., at 360 C), when testing is conducted over a range of dissolved (i.e., aqueous) hydrogen (H{sub 2}) concentrations. It has also been shown that this maximum in SCC susceptibility tends to occur in proximity to the nickel/nickel oxide (Ni/NiO) phase transition, suggesting that oxide phase stability may affect primary water SCC (PWSCC) resistance. Previous studies have estimated the Ni/NiO transition using thermodynamic calculations based on free energies of formation for NiO and H{sub 2}O. The present study reports experimental measurements of the Ni/NiO transition performed using a contact electric resistance (CER) instrument. The CER is capable of measuring the surface resistance of a metal to determine whether it is oxide-covered or oxide-free at a given condition. The transition aqueous hydrogen (H{sub 2}) concentration corresponding to the Ni/NiO equilibrium was measured at 288, 316, 338 and 360 C using high purity Ni specimens. The results showed an appreciable deviation (i.e., 7 to 58 scc H{sub 2}/kg H{sub 2}O) between the measured Ni/NiO transition and the theoretical Ni/NiO transition previously calculated using free energy data from …
Date: May 8, 2001
Creator: Attanasio, S. A.; Morton, D. S.; Ando, M. A.; Panayotou, N. F. & Thompson, C. D.
Object Type: Report
System: The UNT Digital Library
Search for B^0 meson decays to \pi^0 K^0_S K^0_S, \eta K^0_S K^0_S, and \eta^{\prime}K^0_S K^0_S (open access)

Search for B^0 meson decays to \pi^0 K^0_S K^0_S, \eta K^0_S K^0_S, and \eta^{\prime}K^0_S K^0_S

We describe searches for B{sup 0} meson decays to the charmless final states {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}, {eta}K{sub S}{sup 0}K{sub S}{sup 0}, and {eta}{prime}K{sub S}{sup 0}K{sub S}{sup 0}. The data sample corresponds to 467 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation and collected with the BABAR detector at the SLAC National Accelerator Laboratory. We find no significant signals and determine the 90% confidence level upper limits on the branching fractions, in units of 10{sup -7}, {Beta}(B{sup 0} {yields} {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}) < 12, {Beta}(B{sup 0} {yields} {eta}K{sub S}{sup 0}K{sub S}{sup 0}) < 10, and {Beta}(B{sup 0} {yields} {eta}{prime}K{sub S}{sup 0}K{sub S}{sup 0}) < 20.
Date: May 8, 2009
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
CRADA Final Report for CRADA Number ORNL98-0521 : Development of an Electric Bus Inverter Based on ORNL Auxiliary Resonant Tank (ART) Soft-Switching Technology (open access)

CRADA Final Report for CRADA Number ORNL98-0521 : Development of an Electric Bus Inverter Based on ORNL Auxiliary Resonant Tank (ART) Soft-Switching Technology

The Power Electronics and Electric Machinery Research Center (PEEMRC) of Oak Ridge National Laboratory (ORNL) has for many years been developing technologies for power converters for motor drives and many other applications. Some of the research goals are to improve efficiency and reduce audible and electromagnetic interference noise generation for inverters and the driven loads. The converters are being required to produce more power with reduced weight and volume, which requires improvements in heat removal from the electronics, as well as improved circuit designs that have fewer electrical losses. PEEMRC has recently developed and patented a soft-switching inverter topology called an Auxiliary Resonant Tank (ART), and this design has been tested and proven at ORNL using a 10-kW laboratory prototype. The objective of this project was to develop, test, and install the ART inverter technology in an electric transit bus with the final goal of evaluating performance of the ORNL inverter under field conditions in a vehicle. A scaled-up inverter with the capacity to drive a 22-e bus was built based on the 10-kW ORNL laboratory prototype ART soft-switching inverter. Most (if not all) commercially available inverters for traction drive and other applications use hard-switching inverters. A Cooperative Research and …
Date: May 8, 2001
Creator: Ayers, C.W.
Object Type: Report
System: The UNT Digital Library
Sheet Beam Klystron Instability Analysis (open access)

Sheet Beam Klystron Instability Analysis

Using the principle of energy balance we develop a 2D theory for calculating growth rates of instability in a two-cavity model of a sheet beam klystron. An important ingredient is a TE-like mode in the gap that also gives a longitudinal kick to the beam. When compared with a self-consistent particle-in-cell calculation, with sheet beam klystron-type parameters, agreement is quite good up to half the design current, 65 A; at full current, however, other, current-dependent effects come in and the results deviate significantly.
Date: May 8, 2009
Creator: Bane, K. L. F.; Jensen, A.; Li, Z.; Stupakov, G. & Adolphsen, C.
Object Type: Article
System: The UNT Digital Library
RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS (open access)

RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS

Several systems rely on the accurate and linear detection of 500 MHz signals, (the fundamental frequency of both the Booster Ring and Storage Ring) over a dynamic range in excess of 25dB. Prior to this upgrade, the detector/monitor was diode based and though this type of detector could handle the dynamic range requirement it could not do so in an accurate and linear manner. In order to meet the requirements (dynamic range greater than or equal to 25dB, accurate and linear to +-0.25dB over the range, and additional circuitry to interface to the legacy control system and interlocks), a new RF Power Detector/Monitor has been developed using two AD8361, Analog Devices Tru RMS Detectors and a fuzzy comparator, which extends the overall detector's range to twice that of the AD8361. Further information is available [www.analogedevices.com/]. Details of the design requirements and the detector/monitor's circuit as well as the performance of the detector will be presented.
Date: May 8, 2003
Creator: Baptiste, K.
Object Type: Article
System: The UNT Digital Library
Sites of Azaserine Inhibition During Photosynthesis byScenedesmus (open access)

Sites of Azaserine Inhibition During Photosynthesis byScenedesmus

The success attending the use of azaserine as a specific inhibitor of one atage in the metabolic pathway leading to the synthesis of inosinic acid in pigeon liver prompted us to use this antibiotic in a similar attack on purine synthesis in Scenedesmus. However, investigation of the products produced during photosynthesis by suspensions of these algae in the presence of azaserine showed that a more widespread interference with metabolism had occurred. The purpose of this communication is to describe the nature of these effects and to attempt to assess their importance in a general picture of the metabolic effects of azaserine.
Date: May 8, 1956
Creator: Barker, S. Alan; Bassham, James A.; Calvin, M. & Quarck, Ursula C.
Object Type: Report
System: The UNT Digital Library
Enraf series 854 Advanced Technology Gauge (ATG) acceptance test procedure. Revision 3 (open access)

Enraf series 854 Advanced Technology Gauge (ATG) acceptance test procedure. Revision 3

This procedure provides acceptance testing for Enraf Series 854 level gauges used to monitor levels in Hanford Waste Storage Tanks. The test will verify that the gauge functions according to the manufacturer`s instructions and specifications and is properly setup prior to being delivered to the tank farm area.
Date: May 8, 1995
Creator: Barnes, G. A.
Object Type: Report
System: The UNT Digital Library
Merry Go Round (open access)

Merry Go Round

Patent for a merry go round. Illustration included.
Date: May 8, 1906
Creator: Barnett, John B.
Object Type: Patent
System: The Portal to Texas History
Report of a Workshop on Parallelization of Coupled Cluster Methods (open access)

Report of a Workshop on Parallelization of Coupled Cluster Methods

The benchmark, ab initio quantum mechanical methods for molecular structure and spectra are now recognized to be coupled-cluster theory. To benefit from the transiiton to tera- and petascale computers, such coupled-cluster methods must be created to run in a scalable fashion. This Workshop, held as a aprt of the 48th annual Sanibel meeting, at St. Simns, Island, GA, addressed that issue. Representatives of all the principal scientific groups who are addressing this topic were in attendance, to exchange information about the problem and to identify what needs to be done in the future. This report summarized the conclusions of the workshop.
Date: May 8, 2008
Creator: Bartlett, Rodney J. & Deumens, Erik
Object Type: Report
System: The UNT Digital Library
Experimental Evaluation of Tude Support Plate Crevice Chemistry (open access)

Experimental Evaluation of Tude Support Plate Crevice Chemistry

A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation in tubing temperature. Because of the large crevice chemistry gradients during boiling heat transfer and their subsequent homogenization upon test shutdown, the results suggest reassessing the use of hideout return measurements and tube deposit analyses in industry to infer the crevice chemistry under heat transfer conditions.
Date: May 8, 2001
Creator: Baum, Allen
Object Type: Report
System: The UNT Digital Library