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Vibrational Spectroscopy and X-ray Diffraction of Cd(OH)2 to 28GPa at 300 K (open access)

Vibrational Spectroscopy and X-ray Diffraction of Cd(OH)2 to 28GPa at 300 K

We report Raman and infrared absorption spectroscopy alongwith X-ray diffraction for brucite-type beta-Cd(OH)2 to 28 GPa at 300 K.The OH-stretching modes soften with pressure and disappear at 21 GPa withtheir widths increasing rapidly above 5 GPa, consistent with a gradualdisordering of the H sublattice at 5 20 GPa similar to that previouslyobserved for Co(OH)2.Asymmetry in the peak shapes of the OH-stretchingmodes suggests the existence of diverse disordered sitesfor H atoms inCd(OH)2 under pressure. Above 15 GPa, the A1g(T) lattice mode showsnon-linear behavior and softens to 21 GPa, at which pressure significantchanges are observed: new Raman modes appear, two Raman-active latticemodes and the OH-stretching modes of the low-pressure phase disappears,and the positions of some X-ray diffraction lines change abruptly withthe appearance of weak new diffraction features. These observationssuggest that amorphization of the H sublattice is accompanied by acrystalline-to-crystalline transition at 21 GPa in Cd(OH)2, which has notbeen previously observed in the brucite-type hydroxides. The Ramanspectra of the high-pressure phase of Cd(OH)2 is similar to those of thehigh-pressure phase of single-crystal Ca(OH)2 of which structure has beententatively assigned to the Sr(OH)2 type.
Date: March 20, 2006
Creator: Shim, Sang-Heon; Rekhi, Sandeep; Martin, Michael C. & Jeanloz,Raymond
System: The UNT Digital Library
The complete chloroplast genome sequence of Pelargonium xhortorum: Or ganization and evolution of the largest and most highlyrearranged chloroplast genome of land plants (open access)

The complete chloroplast genome sequence of Pelargonium xhortorum: Or ganization and evolution of the largest and most highlyrearranged chloroplast genome of land plants

The chloroplast genome of Pelargonium e hortorum has beencompletely sequenced. It maps as a circular molecule of 217,942 bp, andis both the largest and most rearranged land plant chloroplast genome yetsequenced. It features two copies of a greatly expanded inverted repeat(IR) of 75,741 bp each, and consequently diminished single copy regionsof 59,710 bp and 6,750 bp. It also contains two different associations ofrepeated elements that contribute about 10 percent to the overall sizeand account for the majority of repeats found in the genome. Theyrepresent hotspots for rearrangements and gene duplications and include alarge number of pseudogenes. We propose simple models that account forthe major rearrangements with a minimum of eight IR boundary changes and12 inversions in addition to a several insertions of duplicated sequence.The major processes at work (duplication, IR expansion, and inversion)have disrupted at least one and possibly two or three transcriptionaloperons, and the genes involved in these disruptions form the core of thetwo major repeat associations. Despite the vast increase in size andcomplexity of the genome, the gene content is similar to that of otherangiosperms, with the exceptions of a large number of pseudogenes as partof the repeat associations, the recognition of two open reading frames(ORF56 and ORF42) …
Date: January 20, 2006
Creator: Chumley, Timothy W.; Palmer, Jeffrey D.; Mower, Jeffrey P.; Fourcade, H. Matthew; Calie, Patrick J.; Boore, Jeffrey L. et al.
System: The UNT Digital Library
Sculpting the shape of semiconductor heteroepitaxial islands: fromdots to rods (open access)

Sculpting the shape of semiconductor heteroepitaxial islands: fromdots to rods

In the Ge on Si model heteroepitaxial system, metal patterns on the silicon surface provide unprecedented control over the morphology of highly ordered Ge islands. Island shape including nanorods and truncated pyramids is set by the metal species and substrate orientation. Analysis of island faceting elucidates the prominent role of the metal in promoting growth of preferred facet orientations while investigations of island composition and structure reveal the importance of Si-Ge intermixing in island evolution. These effects reflect a remarkable combination of metal-mediated growth phenomena that may be exploited to tailor the functionality of island arrays in heteroepitaxial systems.
Date: June 20, 2006
Creator: Robinson, J. T.; Walko, D. A.; Arms, D. A.; Tinberg, D. S.; Evans, P. G.; Cao, Y. et al.
System: The UNT Digital Library
MICROFLUIDIC MIXERS FOR THE INVESTIGATION OF PROTEIN FOLDING USING SYNCHROTRON RADIATION CIRCULAR DICHROISM SPECTROSCOPY (open access)

MICROFLUIDIC MIXERS FOR THE INVESTIGATION OF PROTEIN FOLDING USING SYNCHROTRON RADIATION CIRCULAR DICHROISM SPECTROSCOPY

The purpose of this study is to design, fabricate and optimize microfluidic mixers to investigate the kinetics of protein secondary structure formation with Synchrotron Radiation Circular Dichroism (SRCD) spectroscopy. The mixers are designed to rapidly initiate protein folding reaction through the dilution of denaturant. The devices are fabricated out of fused silica, so that they are transparent in the UV. We present characterization of mixing in the fabricated devices, as well as the initial SRCD data on proteins inside the mixers.
Date: March 20, 2006
Creator: Kane, A; Hertzog, D; Baumgartel, P; Lengefeld, J; Horsley, D; Schuler, B et al.
System: The UNT Digital Library
Mobile Data Collection Applications: A Proof of Concept (open access)

Mobile Data Collection Applications: A Proof of Concept

This project's goal is to provide a proof of concept for mobile data collection applications, and identify the best ways such applications could be implemented and used. Such an application should decrease the time and resources users now need to devote to redundant data processes, and provide an easy of locating and retrieving data at a later time. The two types of available mobile devices, Personal Digital Assistants and Tablet Personal Computers, each have their particular strengths that suggest themselves for certain types of applications. As such, parallel data collection applications have been developed, with a common web application for uploading information to the database. While these aspects have been developed and proven, it still remains to refine these applications, develop the tables to hold their data, and field-test with users for their feedback.
Date: September 20, 2006
Creator: Chang, J.
System: The UNT Digital Library
Development of a Fan-Filter Unit Test Standard, Laboratory Validations, and its Applications across Industries (open access)

Development of a Fan-Filter Unit Test Standard, Laboratory Validations, and its Applications across Industries

Lawrence Berkeley National Laboratory (LBNL) is now finalizing the Phase 2 Research and Demonstration Project on characterizing 2-foot x 4-foot (61-cm x 122-cm) fan-filter units in the market using the first-ever standard laboratory test method developed at LBNL.[1][2][3] Fan-filter units deliver re-circulated air and provide particle filtration control for clean environments. Much of the energy in cleanrooms (and minienvironments) is consumed by 2-foot x 4-foot (61-cm x 122-cm) or 4-foot x 4-foot (122-cm x 122-cm) fan-filter units that are typically located in the ceiling (25-100% coverage) of cleanroom controlled environments. Thanks to funding support by the California Energy Commission's Industrial Program of the Public Interest Energy Research (PIER) Program, and significant participation from manufacturers and users of fan-filter units from around the world, LBNL has developed and performed a series of standard laboratory tests and reporting on a variety of 2-foot x 4-foot (61-cm x 122-cm) fan-filter units (FFUs). Standard laboratory testing reports have been completed and reported back to anonymous individual participants in this project. To date, such reports on standard testing of FFU performance have provided rigorous and useful data for suppliers and end users to better understand, and more importantly, to quantitatively characterize performance of FFU products …
Date: October 20, 2006
Creator: Xu, Tengfang
System: The UNT Digital Library
Calculation of Radiative Corrections to Hyperfine Splitting in p1/2 States (open access)

Calculation of Radiative Corrections to Hyperfine Splitting in p1/2 States

Techniques to calculate one-loop radiative corrections to hyperfine splitting including binding corrections to all orders have been developed in the last decade for s states of atoms and ions. In this paper these methods are extended to p{sub 1/2} states for three cases. In the first case, the point-Coulomb 2p{sub 1/2} hyperfine splitting is treated for the hydrogen isoelectronic sequence, and the lowest order result, {alpha}/4{pi} E{sub F}, is shown to have large binding corrections at high Z. In the second case, neutral alkalis are considered. In the third case, hyperfine splitting of the 2p{sub 1/2} state of lithium-like bismuth is treated. In the latter two cases, correlation corrections are included and, in addition, the point is stressed that uncertainties associated with nuclear structure, which complicate comparison with experiment for s states, are considerably reduced because of the smaller overlap with the nucleus.
Date: September 20, 2006
Creator: Sapirstein, J & Cheng, K T
System: The UNT Digital Library
Structures in Molecular Clouds: Modeling (open access)

Structures in Molecular Clouds: Modeling

We attempt to predict the observed morphology, column density and velocity gradient of Pillar II of the Eagle Nebula, using Rayleigh Taylor (RT) models in which growth is seeded by an initial perturbation in density or in shape of the illuminated surface, and cometary models in which structure is arises from a initially spherical cloud with a dense core. Attempting to mitigate suppression of RT growth by recombination, we use a large cylindrical model volume containing the illuminating source and the self-consistently evolving ablated outflow and the photon flux field, and use initial clouds with finite lateral extent. An RT model shows no growth, while a cometary model appears to be more successful at reproducing observations.
Date: April 20, 2006
Creator: Kane, J. O.; Mizuta, A.; Pound, M. W.; Remington, B. A. & Ryutov, D. D.
System: The UNT Digital Library
Pseudomonas aeruginosa forms Biofilms in Acute InfectionIndependent of Cell-to-Cell Signaling (open access)

Pseudomonas aeruginosa forms Biofilms in Acute InfectionIndependent of Cell-to-Cell Signaling

Biofilms are bacterial communities residing within a polysaccharide matrix that are associated with persistence and antibiotic resistance in chronic infections. We show that the opportunistic pathogen Pseudomonas aeruginosa forms biofilms within 8 hours of infection in thermally-injured mice, demonstrating that biofilms contribute to bacterial colonization in acute infections. P. aeruginosa biofilms were visualized within burned tissue surrounding blood vessels and adipose cells. Although quorum sensing (QS), a bacterial signaling mechanism, coordinates differentiation of biofilms in vitro, wild type and QS-deficient P. aeruginosa formed similar biofilms in vivo. Our findings demonstrate that P. aeruginosa forms biofilms on specific host tissues independent of QS.
Date: September 20, 2006
Creator: Schaber, J. Andy; Triffo, W. J.; Suh, Sang J.; Oliver, Jeffrey W.; Hastert, Mary C.; Griswold, John A. et al.
System: The UNT Digital Library
Probabilistic aspects of meteorological and ozone regional ensemble forecasts (open access)

Probabilistic aspects of meteorological and ozone regional ensemble forecasts

This study investigates whether probabilistic ozone forecasts from an ensemble can be made with skill; i.e., high verification resolution and reliability. Twenty-eight ozone forecasts were generated over the Lower Fraser Valley, British Columbia, Canada, for the 5-day period 11-15 August 2004, and compared with 1-hour averaged measurements of ozone concentrations at five stations. The forecasts were obtained by driving the CMAQ model with four meteorological forecasts and seven emission scenarios: a control run, {+-} 50% NO{sub x}, {+-} 50% VOC, and {+-} 50% NO{sub x} combined with VOC. Probabilistic forecast quality is verified using relative operating characteristic curves, Talagrand diagrams, and a new reliability index. Results show that both meteorology and emission perturbations are needed to have a skillful probabilistic forecast system--the meteorology perturbation is important to capture the ozone temporal and spatial distribution, and the emission perturbation is needed to span the range of ozone-concentration magnitudes. Emission perturbations are more important than meteorology perturbations for capturing the likelihood of high ozone concentrations. Perturbations involving NO{sub x} resulted in a more skillful probabilistic forecast for the episode analyzed, and therefore the 50% perturbation values appears to span much of the emission uncertainty for this case. All of the ensembles analyzed …
Date: March 20, 2006
Creator: Monache, L D; Hacker, J; Zhou, Y; Deng, X & Stull, R
System: The UNT Digital Library
Structural Properties of Eu-Doped GaN Investigated by Raman Spectroscopy (open access)

Structural Properties of Eu-Doped GaN Investigated by Raman Spectroscopy

Rare-earth (RE) impurities doped GaN are highly promising candidates for light emitting device applications due to their efficient electroluminescence properties at room temperature. Among those, Eu doped GaN has been identified as an excellent material for the red spectral region due to its strong emission at 620 nm. As a transition internal to the Eu doping atom (4f-4f), light emission originates in a much smaller complex than the more flexibly controllable quantum structures of wells, wires, and dots. This is thought to make the center less susceptible to structural defects and in particular radiation damage in the lattice host. Nevertheless, the lattice host is crucial for providing the excitation in from of free electrons and holes. In this respect, the actual lattice site Eu occupies in the host lattice, i.e. in GaN, is important. A large fraction of Eu atoms are typically inactive which must be attributed to their lattice site and local environment. GaN films implanted with Eu to concentrations of {approx}10{sup 18} cm{sup -3} were subjected to a highly directed beam of 500 keV He{sup +} at a dose of 5 x 10{sup 14} cm{sup -2}. By means of a shadow mask, irradiated and unexposed regions lie very …
Date: June 20, 2006
Creator: Senawiratne, J; Xia, Y; Detchprohm, T; Tringe, J W; Stevens, C G & Wetzel, C
System: The UNT Digital Library
Formation of Pillars at the Boundaries between HII Regions and Molecular Clouds (open access)

Formation of Pillars at the Boundaries between HII Regions and Molecular Clouds

We investigate numerically the hydrodynamic instability of an ionization front (IF) accelerating into a molecular cloud, with imposed initial perturbations of different amplitudes. When the initial amplitude is small, the imposed perturbation is completely stabilized and does not grow. When the initial perturbation amplitude is large enough, roughly the ratio of the initial amplitude to wavelength is greater than 0.02, portions of the IF temporarily separate from the molecular cloud surface, locally decreasing the ablation pressure. This causes the appearance of a large, warm HI region and triggers nonlinear dynamics of the IF. The local difference of the ablation pressure and acceleration enhances the appearance and growth of a multimode perturbation. The stabilization usually seen at the IF in the linear regimes does not work due to the mismatch of the modes of the perturbations at the cloud surface and in density in HII region above the cloud surface. Molecular pillars are observed in the late stages of the large amplitude perturbation case. The velocity gradient in the pillars is in reasonably good agreement with that observed in the Eagle Nebula. The initial perturbation is imposed in three different ways: in density, in incident photon number flux, and in the …
Date: April 20, 2006
Creator: Mizuta, A.; Kane, J. O.; Pound, M. W.; Remington, B. A.; Ryutov, D. D. & Takabe, H.
System: The UNT Digital Library
DESIGN OF A MICROFABRICATED, TWO-ELECTRODE PHASE-CONTRAST ELEMENTSUITABLE FOR ELECTRON MICROSCOPY (open access)

DESIGN OF A MICROFABRICATED, TWO-ELECTRODE PHASE-CONTRAST ELEMENTSUITABLE FOR ELECTRON MICROSCOPY

A miniature electrostatic element has been designed to selectively apply a ninety-degree phase shift to the unscattered beam in the back focal plane of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. The design involves a cylindrically shaped, biased-voltage electrode, which is surrounded by a concentric grounded electrode. Electrostatic calculations have been used to determine that the fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size is greater than 5:1. Unlike the planar, three-electrode einzel lens originally proposed by Boersch for the same purpose, this new design does not require insulating layers to separate the biased and grounded electrodes, and it can thus be produced by a very simple microfabrication process. Scanning electron microscope images confirm that mechanically robust devices with feature sizes of {approx}1 {micro}m can be easily fabricated. Preliminary experimental images demonstrate that these devices do apply a 90-degree phase shift between the scattered and unscattered electrons, as expected.
Date: September 20, 2006
Creator: Cambie, Rossana; Downing, Kenneth H.; Typke, Dieter; Glaeser,Robert M. & Jin, Jian
System: The UNT Digital Library
Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame (open access)

Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame

We present three-dimensional, time-dependent simulations ofthe flowfield of a laboratory-scale slot burner. The simulations areperformed using an adaptive time-dependent low Mach number combustionalgorithm based on a second-order projection formulation that conservesboth species mass and total enthalpy. The methodology incorporatesdetailed chemical kinetics and a mixture model for differential speciesdiffusion. Methane chemistry and transport are modeled using the DRM-19mechanism along with its associated thermodynamics and transportdatabases. Adaptive mesh refinementdynamically resolves the flame andturbulent structures. Detailedcomparisons with experimental measurementsshow that the computational results provide a good prediction of theflame height, the shape of the time-averaged parabolic flame surfacearea, and the global consumption speed (the volume per second ofreactants consumed divided by the area of the time-averaged flame). Thethickness of the computed flamebrush increases in the streamwisedirection, and the flamesurface density profiles display the same generalshapes as the experiment. The structure of the simulated flame alsomatches the experiment; reaction layers are thin (typically thinner than1 mm) and the wavelengths of large wrinkles are 5--10 mm. Wrinklesamplify to become long fingers of reactants which burn through at a neckregion, forming isolated pockets of reactants. Thus both the simulatedflame and the experiment are in the "corrugated flameletregime."
Date: April 20, 2006
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski,Michael J.; Driscoll, James F. & Filatyev, Sergei A.
System: The UNT Digital Library
Coupling Magnetic Fields and ALE Hydrodynamics for 3D Simulations of MFCG's (open access)

Coupling Magnetic Fields and ALE Hydrodynamics for 3D Simulations of MFCG's

We review the development of a full 3D multiphysics code for the simulation of explosively driven Magnetic Flux Compression Generators (MFCG) and related pulse power devices. In a typical MFCG the device is seeded with an initial electric current and the device is then detonated. The detonation compresses the magnetic field and amplifies the current. This is a multiphysics problem in that detonation kinetics, electromagnetic diffusion and induction, material deformation, and thermal effects are all important. This is a tightly coupled problem in that the different physical quantities have comparable spatial and temporal variation, and hence should be solved simultaneously on the same computational mesh.
Date: September 20, 2006
Creator: White, D; Rieben, R & Wallin, B
System: The UNT Digital Library
Progress in Short Period Multilayer Coatings for Water Window Applications (open access)

Progress in Short Period Multilayer Coatings for Water Window Applications

Absolute photoionization cross-section measurements for amixture of ground and metastable states of Xe4+, Xe5+, and Xe6+ arereported in the photon energy range of 4d-nf transitions, which occurwithin or adjacent to the 13.5 nm window for extreme ultravioletlithography light source development. The reported values allow thequantification of opacity effects in xenon plasmas due to these 4d-4fautoionizing states. The oscillator strengths for the 4d-4f and 4d-5ftransitions in Xeq+ (q=1-6) ions are calculated using nonrelativisticHartree-Fock and random phase approximations. These are compared withpublished experimental values for Xe+ to Xe3+ and with the valuesobtained from the present experimental cross-section measurements forXe4+ to Xe6+. The calculations assisted in the determination of themetastable content in the ion beams for Xe5+T and Xe6+. The experimentswere performed by merging a synchrotron photon beam generated by anundulator beamline of the Advanced Light Source with an ion beam producedby an electron cyclotron resonance ion source.
Date: May 20, 2006
Creator: Gullikson, E. M.; Salmassi, F.; Aquila, A. L. & Dollar, F.
System: The UNT Digital Library
A Kalman-filter bias correction of ozone deterministic, ensemble-averaged, and probabilistic forecasts (open access)

A Kalman-filter bias correction of ozone deterministic, ensemble-averaged, and probabilistic forecasts

Kalman filtering (KF) is used to postprocess numerical-model output to estimate systematic errors in surface ozone forecasts. It is implemented with a recursive algorithm that updates its estimate of future ozone-concentration bias by using past forecasts and observations. KF performance is tested for three types of ozone forecasts: deterministic, ensemble-averaged, and probabilistic forecasts. Eight photochemical models were run for 56 days during summer 2004 over northeastern USA and southern Canada as part of the International Consortium for Atmospheric Research on Transport and Transformation New England Air Quality (AQ) Study. The raw and KF-corrected predictions are compared with ozone measurements from the Aerometric Information Retrieval Now data set, which includes roughly 360 surface stations. The completeness of the data set allowed a thorough sensitivity test of key KF parameters. It is found that the KF improves forecasts of ozone-concentration magnitude and the ability to predict rare events, both for deterministic and ensemble-averaged forecasts. It also improves the ability to predict the daily maximum ozone concentration, and reduces the time lag between the forecast and observed maxima. For this case study, KF considerably improves the predictive skill of probabilistic forecasts of ozone concentration greater than thresholds of 10 to 50 ppbv, but …
Date: March 20, 2006
Creator: Monache, L D; Grell, G A; McKeen, S; Wilczak, J; Pagowski, M O; Peckham, S et al.
System: The UNT Digital Library
Synthesis and Stability of a Nanoparticle-Infiltrated Solid OxideFuel Cell Electrode (open access)

Synthesis and Stability of a Nanoparticle-Infiltrated Solid OxideFuel Cell Electrode

Nanoparticulate catalysts infiltrated into SOFC (Solid OxideFUel Cell) electrodes can significantly enhance the cell performance, butthe stability of these electrodes has been an open issue. An infiltrationprocedure is reported that leads to a stable scandia-stablized zirconia(SSZ) cathode electrode performance.
Date: November 20, 2006
Creator: Sholklapper, Tal Z.; Radmilovic, Velimir; Jacobson, Craig P.; Visco, Steven J. & De Jonghe, Lutgard C.
System: The UNT Digital Library
THREE-DIMENSIONAL IGNITION AND GROWTH REACTIVE FLOW MODELING OF PRISM FAILURE TESTS ON PBX 9502 (open access)

THREE-DIMENSIONAL IGNITION AND GROWTH REACTIVE FLOW MODELING OF PRISM FAILURE TESTS ON PBX 9502

The Ignition and Growth reactive flow model for shock initiation and detonation of solid explosives based on triaminotirnitrobenzene (TATB) is applied to three-dimensional detonation wave propagation. The most comprehensive set of three-dimensional detonation wave propagation data is that measured using the trapezoidal prism test. In this test, a PBX 9501 (95% HMX, 2.5% Estane, and 2.5% BDNPA/F) line detonator initiates a detonation wave along the trapezoidal face of a PBX 9502 (95% TATB and 5% Kel-F binder) prism. The failure thickness, which has been shown experimentally to be roughly half of the failure diameter of a long cylindrical charge, is measured after 50 mm of detonation wave propagation by impact with an aluminum witness plate. The effects of confinement impedance on the PBX 9502 failure thickness have been measured using air (unconfined), water, PMMA, magnesium, aluminum, lead, and copper placed in contact with the rectangular faces of the prism parallel to the direction of detonation propagation. These prism test results are modeled using the two-dimensional PBX 9502 Ignition and Growth model parameters determined by calculating failure diameter and tested on recent corner turning experiments. Good agreement between experimentally measured and calculated prism failure thicknesses for unconfined and confined PBX 9502 …
Date: June 20, 2006
Creator: Garcia, M L & Tarver, C M
System: The UNT Digital Library
ENERGY MODULATION OF THE ELECTRONS BY THE LASER FIELD IN THEWIGGLER MAGNET: ANALYSIS AND EXPERIMENT (open access)

ENERGY MODULATION OF THE ELECTRONS BY THE LASER FIELD IN THEWIGGLER MAGNET: ANALYSIS AND EXPERIMENT

Energy modulation of the electron beam after the interactionwith the laser field in the wiggler magnet can be calculated usinginterference of the laser field and the field of spontaneous emission inthe far field region of wiggler radiation. Quite often this approachgives a deeper insight on the process than traditional calculations wherethe effect of the laser field on the electron energy is integrated alongthe electron trajectory in the wiggler. We demonstrate it by showing theagreement between the analytical model and the experiment involvingwiggler scan measurements with large detuning from the FEL resonanceproducing more than one order of magnitude variations in the amplitude ofthe energy modulation. The high sensitivity was achieved using the THzradiation from a sub-mm dip in the electron density that energy modulatedelectrons leave behind while propagating along the storage ring lattice.All measurements were performed at the BESSY-II electron storagering.
Date: August 20, 2006
Creator: Zholents, A.A. & Holldack, K.
System: The UNT Digital Library
Participation through Automation: Fully Automated Critical Peak Pricing in Commercial Buildings (open access)

Participation through Automation: Fully Automated Critical Peak Pricing in Commercial Buildings

California electric utilities have been exploring the use of dynamic critical peak prices (CPP) and other demand response programs to help reduce peaks in customer electric loads. CPP is a tariff design to promote demand response. Levels of automation in DR can be defined as follows: Manual Demand Response involves a potentially labor-intensive approach such as manually turning off or changing comfort set points at each equipment switch or controller. Semi-Automated Demand Response involves a pre-programmed demand response strategy initiated by a person via centralized control system. Fully Automated Demand Response does not involve human intervention, but is initiated at a home, building, or facility through receipt of an external communications signal. The receipt of the external signal initiates pre-programmed demand response strategies. They refer to this as Auto-DR. This paper describes the development, testing, and results from automated CPP (Auto-CPP) as part of a utility project in California. The paper presents the project description and test methodology. This is followed by a discussion of Auto-DR strategies used in the field test buildings. They present a sample Auto-CPP load shape case study, and a selection of the Auto-CPP response data from September 29, 2005. If all twelve sites reached their …
Date: June 20, 2006
Creator: Piette, Mary Ann; Watson, David S.; Motegi, Naoya; Kiliccote,Sila & Linkugel, Eric
System: The UNT Digital Library
Implications of the measurement of the B0s Bbar0s massdifference (open access)

Implications of the measurement of the B0s Bbar0s massdifference

We analyze the significant new model independent constraints on extensions of the standard model (SM) that follow from the recent measurements of the B{sup 0}{sub s} {bar B}{sup 0}{sub s} mass difference. The time-dependent CP asymmetry in B{sub s} {yields} {psi}{phi}, S{sub {psi}{phi}}, will be measured with good precision in the first year of LHC data taking, which will further constrain the parameter space of many extensions of the SM, in particular, next-to-minimal flavor violation. The CP asymmetry in semileptonic B{sub s} decay, A{sup s}{sub SL}, is also important to constrain these frameworks, and could give further clues to our understanding the flavor sector in the LHC era. We point out a strong correlation between S{sub {psi}{phi}} and A{sup s}{sub SL} in a very broad class of new physics models.
Date: April 20, 2006
Creator: Ligeti, Zoltan; Papucci, Michele & Perez, Gilad
System: The UNT Digital Library
Conductivity of carbon nanotube polymer composites (open access)

Conductivity of carbon nanotube polymer composites

Dissipative Particle Dynamics (DPD) simulations were used to investigate methods of controlling the assembly of percolating networks of carbon nanotubes (CNTs) in thin films of block copolymer melts. For suitably chosen polymers the CNTs were found to spontaneously self-assemble into topologically interesting patterns. The mesoscale morphology was projected onto a finite-element grid and the electrical conductivity of the films computed. The conductivity displayed non-monotonic behavior as a function of relative polymer fractions in the melt. Results are compared and contrasted with CNT dispersion in small-molecule fluids and mixtures.
Date: November 20, 2006
Creator: Wescott, J. T.; Kung, P. & Maiti, A.
System: The UNT Digital Library
Partial waves of baryon-antibaryon in three-body B mesondecay (open access)

Partial waves of baryon-antibaryon in three-body B mesondecay

The origin of the reversed angular correlation in thecontext of the pp-bar partial waves in the baryonic decay modes of Bmesons.
Date: September 20, 2006
Creator: Suzuki, Mahiko
System: The UNT Digital Library