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The Greensheet (Houston, Tex.), Vol. 43, No. 109, Ed. 1 Tuesday, April 3, 2012 (open access)

The Greensheet (Houston, Tex.), Vol. 43, No. 109, Ed. 1 Tuesday, April 3, 2012

Free weekly newspaper that includes business and classified advertising.
Date: April 3, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Houston, Tex.), Vol. 43, No. 110, Ed. 1 Tuesday, April 3, 2012 (open access)

The Greensheet (Houston, Tex.), Vol. 43, No. 110, Ed. 1 Tuesday, April 3, 2012

Free weekly newspaper that includes business and classified advertising.
Date: April 3, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
On The Origin Of High Energy Correlations in Gamma-ray Bursts (open access)

On The Origin Of High Energy Correlations in Gamma-ray Bursts

I investigate the origin of the observed correlation between a gamma-ray burst's {nu}F{sub {nu}} spectral peak E{sub pk} and its isotropic equivalent energy E{sub iso} through the use of a population synthesis code to model the prompt gamma-ray emission from GRBs. By using prescriptions for the distribution of prompt spectral parameters as well as the population's luminosity function and co-moving rate density, I generate a simulated population of GRBs and examine how bursts of varying spectral properties and redshift would appear to a gamma-ray detector here on Earth. I find that a strong observed correlation can be produced between the source frame Epk and Eiso for the detected population despite the existence of only a weak and broad correlation in the original simulated population. The energy dependance of a gamma-ray detector's flux-limited detection threshold acts to produce a correlation between the source frame E{sub pk} and E{sub iso} for low luminosity GRBs, producing the left boundary of the observed correlation. Conversely, very luminous GRBs are found at higher redshifts than their low luminosity counterparts due to the standard Malquest bias, causing bursts in the low E{sub pk}, high E{sub iso} regime to go undetected because their E{sub pk} values would …
Date: April 3, 2012
Creator: Kocevski, Daniel
Object Type: Article
System: The UNT Digital Library
RECOMMENDED TRITIUM OXIDE DEPOSITION VELOCITY FOR USE IN SAVANNAH RIVER SITE SAFETY ANALYSES (open access)

RECOMMENDED TRITIUM OXIDE DEPOSITION VELOCITY FOR USE IN SAVANNAH RIVER SITE SAFETY ANALYSES

The Defense Nuclear Facilities Safety Board (DNFSB) has recently questioned the appropriate value for tritium deposition velocity used in the MELCOR Accident Consequence Code System Ver. 2 (Chanin and Young 1998) code when estimating bounding dose (95th percentile) for safety analysis (DNFSB 2011). The purpose of this paper is to provide appropriate, defensible values of the tritium deposition velocity for use in Savannah River Site (SRS) safety analyses. To accomplish this, consideration must be given to the re-emission of tritium after deposition. Approximately 85% of the surface area of the SRS is forested. The majority of the forests are pine plantations, 68%. The remaining forest area is 6% mixed pine and hardwood and 26% swamp hardwood. Most of the path from potential release points to the site boundary is through forested land. A search of published studies indicate daylight, tritiated water (HTO) vapor deposition velocities in forest vegetation can range from 0.07 to 2.8 cm/s. Analysis of the results of studies done on an SRS pine plantation and climatological data from the SRS meteorological network indicate that the average deposition velocity during daylight periods is around 0.42 cm/s. The minimum deposition velocity was determined to be about 0.1 cm/s, which …
Date: April 3, 2012
Creator: Lee, P.; Murphy, C.; Viner, B.; Hunter, C. & Jannik, T.
Object Type: Report
System: The UNT Digital Library
Laser Welding and Post Weld Treatment of Modified 9cr-1movnb Steel. (open access)

Laser Welding and Post Weld Treatment of Modified 9cr-1movnb Steel.

Laser welding and post weld laser treatment of modified 9Cr-1MoVNb steels (Grade P91) were performed in this preliminary study to investigate the feasibility of using laser welding process as a potential alternative to arc welding methods for solving the Type IV cracking problem in P91 steel welds. The mechanical and metallurgical testing of the pulsed Nd:YAG laser-welded samples shows the following conclusions: (1) both bead-on-plate and circumferential butt welds made by a pulsed Nd:YAG laser show good welds that are free of microcracks and porosity. The narrow heat affected zone has a homogeneous grain structure without conventional soft hardness zone where the Type IV cracking occurs in conventional arc welds. (2) The laser weld tests also show that the same laser welder has the potential to be used as a multi-function tool for weld surface remelting, glazing or post weld tempering to reduce the weld surface defects and to increase the cracking resistance and toughness of the welds. (3) The Vicker hardness of laser welds in the weld and heat affected zone was 420-500 HV with peak hardness in the HAZ compared to 240 HV of base metal. Post weld laser treatment was able to slightly reduce the peak hardness …
Date: April 3, 2012
Creator: Xu, Z. (Nuclear Engineering Division)
Object Type: Report
System: The UNT Digital Library
Cellulose and cellobiose: adventures of a wandering organic chemist in theoretical chemistry (open access)

Cellulose and cellobiose: adventures of a wandering organic chemist in theoretical chemistry

The energies arising from the rotation of free hydroxyl groups in the central glucose residue of a cellulose crystalline assembly, calculated using RHF, DFT, and FMO2/MP2 methods, will be presented. In addition, interactions of this central glucose residue with some of the surrounding residues (selected on the basis of the interaction strengths) are analyzed. The mechanism of acid-catalyzed hydrolysis of cellobiose, which is the repeating unit of cellulose. Energies corresponding to the different steps of this mechanism calculated using RHF and DFT are compared with those previously reported using molecular dynamics calculations and with experimental data.
Date: April 3, 2012
Creator: Baluyut, John
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Variations in Map Products Demonstrated During the FRMAC Fukushima Daiichi Response (open access)

Variations in Map Products Demonstrated During the FRMAC Fukushima Daiichi Response

This presentation provides a brief summary of the Fukushima Daiichi disaster, discussion on map uses and production, early phase maps, intermediate phase maps, and late phase maps.
Date: April 3, 2012
Creator: Pemberton, W. J.
Object Type: Article
System: The UNT Digital Library
Combined Fit to BaBar and Belle Data on E E- to Phi Pi+ Pi- and Phi F0(980) (open access)

Combined Fit to BaBar and Belle Data on E E- to Phi Pi+ Pi- and Phi F0(980)

A combined fit is performed to the BaBar and Belle measurements of the e{sup +}e{sup -} {yields} {phi}{pi}{sup +}{pi}{sup -} and {phi}f{sub 0}(980) cross sections for center-of-mass energy between threshold and 3.0 GeV. The resonance parameters of the {phi}(1680) and Y(2175) are determined. The mass is (1681{sub -12}{sup +10}) MeV/c{sup 2} and the width is (221{sub -24}{sup +34}) MeV/c{sup 2} for the {phi}(1680), and the mass is (2117{sub -49}{sup +59}) MeV/c{sup 2} and the width is (164{sub -80}{sup +69}) MeV/c{sup 2} for the Y(2175). These information will shed light on the understanding of the nature of the excited {phi} and Y states observed in e{sup +}e{sup -} annihilation.
Date: April 3, 2012
Creator: Shen, C. P. & Yuan, C. Z.
Object Type: Article
System: The UNT Digital Library
Analyticity and the Holographic S-Matrix (open access)

Analyticity and the Holographic S-Matrix

We derive a simple relation between the Mellin amplitude for AdS/CFT correlation functions and the bulk S-Matrix in the flat spacetime limit, proving a conjecture of Penedones. As a consequence of the Operator Product Expansion, the Mellin amplitude for any unitary CFT must be a meromorphic function with simple poles on the real axis. This provides a powerful and suggestive handle on the locality vis-a-vis analyticity properties of the S-Matrix. We begin to explore analyticity by showing how the familiar poles and branch cuts of scattering amplitudes arise from the holographic description. For this purpose we compute examples of Mellin amplitudes corresponding to 1-loop and 2-loop Witten diagrams in AdS. We also examine the flat spacetime limit of conformal blocks, implicitly relating the S-Matrix program to the Bootstrap program for CFTs. We use this connection to show how the existence of small black holes in AdS leads to a universal prediction for the conformal block decomposition of the dual CFT.
Date: April 3, 2012
Creator: Fitzpatrick, A.Liam; /Stanford U., Phys. Dept. & Kaplan, Jared
Object Type: Article
System: The UNT Digital Library
Photoluminescence of Diamondoid Crystals (open access)

Photoluminescence of Diamondoid Crystals

The photoluminescence of diamondoids in the solid state is examined. All of the diamondoids are found to photoluminesce readily with initial excitation wavelengths ranging from 233 nm to 240 nm (5.3 eV). These excitation energies are more than 1 eV lower than any previously studied saturated hydrocarbon material. The emission is found to be heavily shifted from the absorption, with emission wavelengths of roughly 295 nm (4.2 eV) in all cases. In the dissolved state, however, no uorescence is observed for excitation wavelengths as short as 200 nm. We also discuss predictions and measurements of the quantum yield. Our predictions indicate that the maximum yield may be as high as 25%. Our measurement of one species, diamantane, gives a yield of 11%, the highest ever reported for a saturated hydrocarbon, even though it was likely not at the optimal excitation wavelength.
Date: April 3, 2012
Creator: Clay, William; /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.; Sasagawa, Takao; Iwasa, Akio; /TIT, Nagatsuta; Liu, Zhi et al.
Object Type: Article
System: The UNT Digital Library
Heavy Flavor Simplified Models at the LHC (open access)

Heavy Flavor Simplified Models at the LHC

We consider a comprehensive set of simplified models that contribute to final states with top and bottom quarks at the LHC. These simplified models are used to create minimal search strategies that ensure optimal coverage of new heavy flavor physics involving the pair production of color octets and triplets. We provide a set of benchmarks that are representative of model space, which can be used by experimentalists to perform their own optimization of search strategies. For data sets larger than 1 fb{sup -1}, same-sign dilepton and 3b search regions become very powerful. Expected sensitivities from existing and optimized searches are given.
Date: April 3, 2012
Creator: Essig, Rouven; Izaguirre, Eder; Kaplan, Jared & Wacker, Jay G.
Object Type: Article
System: The UNT Digital Library
Dark Matter Particle Spectroscopy at the LHC: Generalizing M(T2) to Asymmetric Event Topologies (open access)

Dark Matter Particle Spectroscopy at the LHC: Generalizing M(T2) to Asymmetric Event Topologies

We consider SUSY-like missing energy events at hadron colliders and critically examine the common assumption that the missing energy is the result of two identical missing particles. In order to experimentally test this hypothesis, we generalize the subsystem M{sub T2} variable to the case of asymmetric event topologies, where the two SUSY decay chains terminate in different 'children' particles. In this more general approach, the endpoint M{sub T2(max)} of the M{sub T2} distribution now gives the mass {tilde M}p({tilde M}{sub c}{sup (a)}, {tilde M}{sub c}{sup (b)}) of the parent particles as a function of two input children masses {tilde M}{sub c}{sup (a)} and {tilde M}{sub c}{sup (b)}. We propose two methods for an independent determination of the individual children masses M{sub c}{sup (a)} and M{sub c}{sup (b)}. First, in the presence of upstream transverse momentum PUTM the corresponding function {tilde M}p({tilde M}{sub c}{sup (a)}, {tilde M}{sub c}{sup (b)}, P{sub UTM}) is independent of P{sub UTM} at precisely the right values of the children masses. Second, the previously discussed MT2 'kink' is now generalized to a 'ridge' on the 2-dimensional surface {tilde M}p({tilde M}{sub c}{sup (a)}, {tilde M}{sub c}{sup (b)}). As we show in several examples, quite often there is a …
Date: April 3, 2012
Creator: Konar, Partha; Kong, Kyoungchul; Matchev, Konstantin T. & Park, Myeonghun
Object Type: Article
System: The UNT Digital Library
Charmonium Spectroscopy (X,Y,Z) at the B Factories (open access)

Charmonium Spectroscopy (X,Y,Z) at the B Factories

Since 2003 several states in the charmonium mass region were discovered. While in the conventional c{bar c} spectrum some states are missing, the number of states observed up to now is larger than empty spaces in the c{bar c} spectrum. This, together with other difficulties to explain observed states as a c{bar c} mesons triggered discussions on a possible exotic interpretations. In this proceedings we present current experimental status from B-factories of the so called X, Y and Z states.
Date: April 3, 2012
Creator: Kreps, Michal & U., /Karlsruhe
Object Type: Article
System: The UNT Digital Library
Bottomonium Results By BaBar (open access)

Bottomonium Results By BaBar

Summary: Observation of {eta}{sub b}; Energy scan above {Upsilon}(4S); Search for {Upsilon} {r_arrow} {gamma}A{sup 0}, A{sup 0} {r_arrow} invisible; Hadronic transitions {Upsilon}(4S) {r_arrow} {Upsilon}(nS).
Date: April 3, 2012
Creator: Tosi, Silvano & /Genoa U. /INFN, Genoa
Object Type: Article
System: The UNT Digital Library
STOMP Subsurface Transport Over Multiple Phases: STOMP-CO2 and STOMP-CO2e Guide: Version 1.0 (open access)

STOMP Subsurface Transport Over Multiple Phases: STOMP-CO2 and STOMP-CO2e Guide: Version 1.0

This STOMP (Subsurface Transport Over Multiple Phases) guide document describes the theory, use, and application of the STOMP-CO2 and STOMP-CO2e operational modes. These operational modes of the STOMP simulator are configured to solve problems involving the sequestration of CO2 in geologic saline reservoirs. STOMP-CO2 is the isothermal version and STOMP-CO2e is the nonisothermal version. These core operational modes solve the governing conservation equations for component flow and transport through geologic media; where, the STOMP-CO2 components are water, CO2 and salt and the STOMP-CO2e operational mode also includes an energy conservation equation. Geochemistry can be included in the problem solution via the ECKEChem (Equilibrium-Conservation-Kinetic-Equation Chemistry) module, and geomechanics via the EPRMech (Elastic-Plastic-Rock Mechanics) module. This addendum is designed to provide the new user with a full guide for the core capabilities of the STOMP-CO2 and -CO2e simulators, and to provide the experienced user with a quick reference on implementing features. Several benchmark problems are provided in this addendum, which serve as starting points for developing inputs for more complex problems and as demonstrations of the simulator’s capabilities.
Date: April 3, 2012
Creator: White, Mark D.; Bacon, Diana H.; McGrail, B. Peter; Watson, David J.; White, Signe K. & Zhang, Z. F.
Object Type: Report
System: The UNT Digital Library
MODELING TRITIUM TRANSPORT, DEPOSITION AND RE-EMISSION (open access)

MODELING TRITIUM TRANSPORT, DEPOSITION AND RE-EMISSION

The atmospheric release of tritium oxide (HTO) potentially impacts human health, typically through inhalation or absorption. Due to HTO's similarity to water, vegetation will absorb HTO by solution in the leaf water and then re-emit it, creating a number of secondary sources of HTO. Currently, models used for emergency response at Savannah River Site incorporate the transport and deposition of HTO but do not provide estimates for its potential re-emission from vegetation or soil surface though re-emission could result in prolonged exposure and greater than predicted dose for an individual downwind. A simple model of HTO transport, deposition and re-emission has been developed to examine the potential increase in exposure and dose. The model simulates an initial release of HTO that moves with a mean wind and expands through diffusion as a Gaussian puff. Deposition is modeled using previous estimates of deposition velocity for HTO and re-emission is modeled using a time constant that describes how quickly HTO is transferred between the surface and atmosphere. Additional puffs are created to simulate re-emission of HTO as well as horizontal diffusion across model grid cells. An evaluation of field data indicates that the use of a re-emission module tends to improve model …
Date: April 3, 2012
Creator: Viner, B.
Object Type: Report
System: The UNT Digital Library
[Email from Robert Emery to William Waybourn, April 3, 2012] (open access)

[Email from Robert Emery to William Waybourn, April 3, 2012]

Email from Robert Emery to William Waybourn discussing an essay about the Crossroads Market.
Date: April 3, 2012
Creator: Emery, Robert
Object Type: Letter
System: The UNT Digital Library
[Minutes: The Dallas Way, April 3, 2012] (open access)

[Minutes: The Dallas Way, April 3, 2012]

Minutes for the April 3rd meeting of the Dallas Way including current reports on organization projects.
Date: April 3, 2012
Creator: The Dallas Way
Object Type: Text
System: The UNT Digital Library
[Agenda: The Dallas Way, April 3, 2012] (open access)

[Agenda: The Dallas Way, April 3, 2012]

Agenda for the April 3rd meeting of the Dallas Way, including topics such as current reports and new Dallas Way business.
Date: April 3, 2012
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Oral History Interview with Richard Clay McBride, April 3, 2012 (open access)

Oral History Interview with Richard Clay McBride, April 3, 2012

Interview with Richard Clay McBryde, a rancher from Kerrville, Texas. Mr. McBryde discusses his life as a rancher, his rodeo career, his education, and his short-lived football career. The interview transcript includes photos of Richard Clay McBryde, his rodeo years, and his family, on pages 16-21.
Date: April 3, 2012
Creator: Collins, Francelle Robison; Stephens, Louis & McBryde, Richard Clay
Object Type: Text
System: The Portal to Texas History
Rains County Leader (Emory, Tex.), Vol. 125, No. 42, Ed. 1 Tuesday, April 3, 2012 (open access)

Rains County Leader (Emory, Tex.), Vol. 125, No. 42, Ed. 1 Tuesday, April 3, 2012

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: April 3, 2012
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 99, No. 41, Ed. 1 Tuesday, April 3, 2012 (open access)

North Texas Daily (Denton, Tex.), Vol. 99, No. 41, Ed. 1 Tuesday, April 3, 2012

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state, and campus news along with advertising.
Date: April 3, 2012
Creator: Gorman, Sean
Object Type: Newspaper
System: The Portal to Texas History
Sweetwater Reporter (Sweetwater, Tex.), Vol. 114, No. 066, Ed. 1 Tuesday, April 3, 2012 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 114, No. 066, Ed. 1 Tuesday, April 3, 2012

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: April 3, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Ring Walking/Oxidative Addition Reactions for the Controlled Synthesis of Conjugated Polymers (open access)

Ring Walking/Oxidative Addition Reactions for the Controlled Synthesis of Conjugated Polymers

Power conversion efficiencies of plastic solar cells depend strongly on the molecular weight characteristics of the semiconducting polymers used for their fabrication. The synthesis of these materials typically relies on transition metal mediated catalytic reactions. In many instances, the ideal structures cannot be attained because of deficiencies in these reactions, particularly when it comes to being able to achieve high number average molecular weights and narrow molecular weight distributions. Another important conjugated polymer structure of interest is one in which a single functional group is attached at the end group of the chain. Such systems would be ideal for modifying surface properties at interfaces and for labeling biomolecular probes used in fluorescent biosensors. To respond to the challenges above, our efforts have centered on the design of homogenous transition metal complexes that are easy to prepare and effective in carrying out living, or quasi-living, condensative chain polymerization reactions. The key mechanistic challenge for the success of this reaction is to force the insertion of one monomer unit at a time via a process that involves migration of the transition metal-containing fragment to one terminus of the polymer chain. Chain growth characteristics are therefore favored when the metal does not dissociate …
Date: April 3, 2012
Creator: Bazan, Guillermo C
Object Type: Report
System: The UNT Digital Library