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Sun-Climate Complexity Linking

Description: Article discussing sun-climate complexity linking and how this property is a consequence of the phenomenon of information transfer.
Date: February 29, 2008
Creator: West, Bruce J. & Grigolini, Paolo
Partner: UNT College of Arts and Sciences
open access

Design study of a DPIS injector for a heavy ion FFAG

Description: A new heavy ion injector linac is proposed for providing heavy ion beams to a fixed field alternating gradient (FFAG) accelerator in Kyushu University. A combination of the new intense laser source based injector and the FFAG will be able to accelerate high current ion beams with 100 Hz of a repetition rate. The planned average current reaches 7 {micro}A with carbon 6+ beam.
Date: September 29, 2008
Creator: Okamura,M.; Raparia, D.; Ishibashi, K.; Yonemura, Y. & Kanesue, T.
Partner: UNT Libraries Government Documents Department
open access

Electric-dipole 5s - 5p Transitions in Promethiumlike Ions

Description: The 5s-5p electric-dipole resonance transitions in highly ionized promethiumlike ions have been studied applying relativistic multi-reference Moeller-Plesset second-order perturbation theory. The transition wavelengths are determined to within 0.2 {angstrom} in the more highly charged ions, where the level degeneracies are small. For somewhat lighter ions a very large reference space was used in order to account for the many degeneracies. In order to calculate transition probabilities and lifet… more
Date: February 29, 2008
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department
open access

Rh(I)-Catalyzed Direct Arylation of Pyridines and Quinolines

Description: The pyridine and quinoline nuclei are privileged scaffolds that occupy a central role in many medicinally relevant compounds. Consequently, methods for their expeditious functionalization are of immediate interest. However, despite the immense importance of transition-metal catalyzed cross-coupling for the functionalization of aromatic scaffolds, general solutions for coupling 2-pyridyl organometallics with aryl halides have only recently been presented. Direct arylation at the ortho position o… more
Date: July 29, 2008
Creator: Berman, Ashley; Lewis, Jared; Bergman, Robert & Ellman, Jonathan
Partner: UNT Libraries Government Documents Department
open access

Investigation of the 2p3/2-3d5/2 line emission of Au53+ -- Au69+ for diagnosing high energy density plasmas

Description: Measurements of the L-shell emission of highly charged gold ions were made under controlled laboratory conditions using the SuperEBIT electron beam ion trap, allowing detailed spectral observations of lines from ironlike Au{sup 53+} through neonlike Au{sup 69+}. Using atomic data from the Flexible Atomic Code, we have identified strong 3d{sub 5/2} {yields} 2p{sub 3/2} emission features that can be used to diagnose the charge state distribution in high energy density plasmas, such as those found… more
Date: January 29, 2008
Creator: Brown, G V; Hansen, S B; Trabert, E; Beiersdorfer, P; Widmann, K; Chen, H et al.
Partner: UNT Libraries Government Documents Department
open access

Electronic structure effects in liquid water studied by photoelectron spectroscopy and density functional theory

Description: We present valence photoelectron emission spectra of liquid water in comparison with gas-phase water, ice close to the melting point, low temperature amorphous and crystalline ice. All aggregation states have major electronic structure changes relative to the free molecule, with rehybridization and development of bonding and anti-bonding states accompanying the hydrogen bond formation. Sensitivity to the local structural order, most prominent in the shape and splitting of the occupied 3a{sub 1}… more
Date: April 29, 2008
Creator: Nordlund, Dennis; Odelius, Michael; Bluhm, Hendrik; Ogasawara, Hirohito; Pettersson, Lars G.M. & Nilsson, Anders
Partner: UNT Libraries Government Documents Department
open access

The Origins of the Rate Enhancement in LiNi0.4Co0.2-yAlyMn0.4O2 (0<y<_0.2) Cathode Materials

Description: Recently, much research has been directed towards finding a replacement cathode material for LiCoO{sub 2} combining high performance with lower cost and toxicity. One promising candidate material is the mixed transition metal oxide LiNi{sub 0.4}Co{sub 0.2}Mn{sub 0.4}O{sub 2}, which delivers 180 mAh/g below 4.4 V versus Li/Li{sup +} (1, 2). However, in this material, there is 4% anti-site cation mixing, which hinders the mobility of lithium within the lattice, adversely affecting its rate perfor… more
Date: May 29, 2008
Creator: Doeff, Marca M; Wilcox, James & Doeff, Marca M.
Partner: UNT Libraries Government Documents Department
open access

Worldlines as Wilson Lines

Description: Gravitational theories do not admit gauge invariant local operators. We study the limits under which there exists a quasi-local description for a class of non-local gravitational observables where a sum over worldlines plays the role of the Wilson line for gauge theory observables. We study non-local corrections to the local description and circumstances where these corrections become large. We find that these operators are quasi-local in at space and AdS, but fail to be quasi-local in de Sitte… more
Date: April 29, 2008
Creator: Green, Daniel & /SLAC /Stanford U., Dept. Phys.
Partner: UNT Libraries Government Documents Department
open access

CONSTRAINT EFFECT IN FRACTURE WHAT IS IT

Description: The meaning of the phrase 'constraint effect in fracture' has changed in the past two decades from 'contained plasticity' to a broader description of 'dependence of fracture toughness value on geometry of test specimen or structure'. This paper will first elucidate the fundamental mechanics reasons for the apparent 'constraint effects in fracture', followed by outlining a straightforward approach to overcoming this problem in both brittle (elastic) and ductile (elastic-plastic) fracture. It is … more
Date: October 29, 2008
Creator: Lam, P & Prof. Yuh J. Chao, P
Partner: UNT Libraries Government Documents Department
open access

Rapid Reagentless Detection of M. tuberculosis H37Ra in Respiratory Effluents

Description: Two similar mycobacteria, Mycobacteria tuberculosis H37Ra and Mycobacteria smegmatis are rapidly detected and identified within samples containing a complex background of respiratory effluents using Single Particle Aerosol Mass Spectrometry (SPAMS). M. tuberculosis H37Ra (TBa), an avirulent strain, is used as a surrogate for virulent tuberculosis (TBv); M. smegmatis (MSm) is utilized as a near neighbor confounder for TBa. Bovine lung surfactant and human exhaled breath condensate are used as fi… more
Date: January 29, 2008
Creator: Adams, K L; Steele, P T; Bogan, M J; Sadler, N M; Martin, S; Martin, A N et al.
Partner: UNT Libraries Government Documents Department
open access

Dirac charge dynamics in graphene by infrared spectroscopy

Description: A remarkable manifestation of the quantum character of electrons in matter is offered by graphene, a single atomic layer of graphite. Unlike conventional solids where electrons are described with the Schr&#246;dinger equation, electronic excitations in graphene are governed by the Dirac hamiltonian. Some of the intriguing electronic properties of graphene, such as massless Dirac quasiparticles with linear energy-momentum dispersion, have been confirmed by recent observations. Here, we report an… more
Date: April 29, 2008
Creator: Martin, Michael C.; Li, Z. Q.; Henriksen, E. A.; Jiang, Z.; Hao, Z.; Martin, Michael C et al.
Partner: UNT Libraries Government Documents Department
open access

Direct Photons at RHIC

Description: Direct photons are ideal tools to investigate kinematical and thermodynamical conditions of heavy ion collisions since they are emitted from all stages of the collision and once produced they leave the interaction region without further modification by the medium. The PHENIX experiment at RHIC has measured direct photon production in p+p and Au+Au collisions at 200 GeV over a wide transverse momentum (p{sub T}) range. The p+p measurements allow a fundamental test of QCD, and serve as a baseline… more
Date: July 29, 2008
Creator: Gabor,D.
Partner: UNT Libraries Government Documents Department
open access

Design and Construction Solutions in the Accurate Realization of NCSX Magnetic Fields

Description: The National Compact Stellarator Experiment, NCSX, is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge national Laboratory. The goal of NCSX is to provide the understanding necessary to develop an attractive, disruption free, steady state compact stellaratorbased reactor design. This paper describes the recently revised designs of the critical interfaces between the modular coils, the construction solutions developed to meet assembly toleranc… more
Date: September 29, 2008
Creator: Heitzenroeder, P.; Dudek, Lawrence E.; Brooks, Arthur W.; Viola, Michael E.; Brown, Thomas; Neilson, George H. et al.
Partner: UNT Libraries Government Documents Department
open access

Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

Description: Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel elec… more
Date: April 29, 2008
Creator: Stenerlöw, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn & Stenerlow, Bo
Partner: UNT Libraries Government Documents Department
open access

Correlations between Optical, Chemical and Physical Properties of Biomass Burn Aerosols

Description: Aerosols generated from burning different plant fuels were characterized to determine relationships between chemical, optical and physical properties. Single scattering albedo ({omega}) and Angstrom absorption coefficients ({alpha}{sub ap}) were measured using a photoacoustic technique combined with a reciprocal nephelometer. Carbon-to-oxygen atomic ratios, sp{sup 2} hybridization, elemental composition and morphology of individual particles were measured using scanning transmission X-ray micro… more
Date: January 29, 2008
Creator: Hopkins, Rebecca J.; Lewis, K.; Desyaterik, Yury; Wang, Z.; Tivanski, Alexei V.; Arnott, W. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Magnetic structure near the Co/NiO(001) interface

Description: We investigate the magnetic coupling at the Co/NiO interface using soft x-ray magnetic linear dichroism (XMLD) and circular dichroism taking explicitly into account the recently observed angular dependence of the XMLD with respect to the crystallographic axes. We find that the Co moments are aligned perpendicular to the NiO moments. We discuss the impact of the anisotropic XMLD on the intensity ratio of the two peaks at the Ni L{sub 2} edge, which is commonly employed to determine the spin orie… more
Date: August 29, 2008
Creator: Arenholz, Elke; van der Laan, Gerrit & Nolting, Frithjof
Partner: UNT Libraries Government Documents Department
open access

QUALIFICATION OF A RADIOACTIVE HIGH ALUMINUM GLASS FOR PROCESSINGIN THE DEFENSE WASTE PROCESSING FACILITY AT THE SAVANNAH RIVER SITE

Description: At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a borosilicate glass for approximately eleven years. Currently the DWPF is immobilizing HLW sludge in Sludge Batch 4 (SB4). Each sludge batch is nominally two million liters of HLW and produces nominally five hundred stainless steel canisters 0.6 meters in diameter and 3 meters tall filled with the borosilicate glass. In SB4 and earlier sludge … more
Date: January 29, 2008
Creator: Bibler, N; John Pareizs, J; Tommy Edwards,T; Charles02 Coleman, C & Charles Crawford, C
Partner: UNT Libraries Government Documents Department
open access

Triple Differential Cross sections and Nuclear Recoil in Two-Photon Double Ionization of Helium

Description: Triple differential cross sections (TDCS) for two-photon double ionization of helium are calculated using the method of exterior complex scaling both above and below the threshold for sequential ionization (54.4 eV). It is found that sequential ionization produces characteristic behavior in the TDCS that identifies that process when it is in competition with nonsequential ionization. Moreover we see the signature in the TDCS and nuclear recoil cross sections of&quot;virtual sequential ionizatio… more
Date: April 29, 2008
Creator: Horner, Daniel A.; McCurdy, C. William & Rescigno, Thomas N
Partner: UNT Libraries Government Documents Department
open access

Laser-based profile and energy monitor for H beams

Description: A beam profile and energy monitor for H{sup -} beams based on laser photoneutralization was built at Brookhaven National Laboratory (BNL)* for use on the High Intensity Neutrino Source (HMS) at Fermilab. An H{sup -} ion has a first ionization potential of 0.75eV and can be neutralized by light from a Nd:YAG laser ({lambda}=1064nm). To measure beam profiles, a narrow laser beam is stepped across the ion beam, removing electrons from the portion of the H{sup -} beam intercepted by the laser. Thes… more
Date: September 29, 2008
Creator: Connolly, R.; Alessi, J.; Bellavia, S.; Dawson, C.; Degen, C.; Meng, W. et al.
Partner: UNT Libraries Government Documents Department
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