Collaborative National Program for the Development and Performance Testing of Distributed Power Technologies with Emphasis on Combined Heat and Power Applications (open access)

Collaborative National Program for the Development and Performance Testing of Distributed Power Technologies with Emphasis on Combined Heat and Power Applications

A current barrier to public acceptance of distributed generation (DG) and combined heat and power (CHP) technologies is the lack of credible and uniform information regarding system performance. Under a cooperative agreement, the Association of State Energy Research and Technology Transfer Institutions (ASERTTI) and the U.S. Department of Energy have developed four performance testing protocols to provide a uniform basis for comparison of systems. The protocols are for laboratory testing, field testing, long-term monitoring and case studies. They have been reviewed by a Stakeholder Advisory Committee made up of industry, public interest, end-user, and research community representatives. The types of systems covered include small turbines, reciprocating engines (including Stirling Cycle), and microturbines. The protocols are available for public use and the resulting data is publicly available in an online national database and two linked databases with further data from New York State. The protocols are interim pending comments and other feedback from users. Final protocols will be available in 2007. The interim protocols and the national database of operating systems can be accessed at www.dgdata.org. The project has entered Phase 2 in which protocols for fuel cell applications will be developed and the national and New York databases will continue …
Date: June 28, 2006
Creator: Soinski, Arthur & Hanson, Mark
Object Type: Report
System: The UNT Digital Library
Confronting X-Ray Emission Models with theHighest-Redshift Kiloparsec-Scale Jets: The z = 3.89 Jet in Quasar 1745+624 (open access)

Confronting X-Ray Emission Models with theHighest-Redshift Kiloparsec-Scale Jets: The z = 3.89 Jet in Quasar 1745+624

A newly identified kiloparsec-scale X-ray jet in the high-redshift z=3.89 quasar 1745+624 is studied with multi-frequency Very Large Array, Hubble Space Telescope, and Chandra X-ray imaging data. This is only the third large-scale X-ray jet beyond z > 3 known and is further distinguished as being the most luminous relativistic jet observed at any redshift, exceeding 10{sup 45} erg/s in both the radio and X-ray bands. Apart from the jet's extreme redshift, luminosity, and high inferred equipartition magnetic field (in comparison to local analogues), its basic properties such as X-ray/radio morphology and radio polarization are similar to lower-redshift examples. Its resolved linear structure and the convex broad-band spectral energy distributions of three distinct knots are also a common feature among known powerful X-ray jets at lower-redshift. Relativistically beamed inverse Compton and ''non-standard'' synchrotron models have been considered to account for such excess X-ray emission in other jets; both models are applicable to this high-redshift example but with differing requirements for the underlying jet physical properties, such as velocity, energetics, and electron acceleration processes. One potentially very important distinguishing characteristic between the two models is their strongly diverging predictions for the X-ray/radio emission with increasing redshift. This is considered, though with …
Date: June 28, 2006
Creator: Cheung, C.C.; /KIPAC, Menlo Park; Stawarz, L.; Observ., /Heidelberg; Siemiginowska, A. & Astrophys., /Harvard-Smithsonian Ctr.
Object Type: Report
System: The UNT Digital Library
Dynamical GUT Breaking and mu-term Driven Supersymmetry Breaking (open access)

Dynamical GUT Breaking and mu-term Driven Supersymmetry Breaking

Models for dynamical breaking of supersymmetric grand unified theories are presented. The doublet-triplet splitting problem is absent since the Higgs doublet superfields can be identified with the massless mesons of the strong gauge group whereas there are no massless states corresponding to the colored Higgs fields. Various strong gauge groups SU(N{sub c}), Sp(N{sub c}) and SO(N{sub c}) are examined. In a model with SO(9) strong gauge group, adding the {mu}-term for the Higgs fields triggers to break supersymmetry in a meta-stable vacuum. The pattern of the supersymmetry breaking parameters is predicted to be the gauge-mediation type with modifications in the Higgs sector.
Date: June 28, 2006
Creator: Kitano, Ryuichiro
Object Type: Report
System: The UNT Digital Library
Equation of state for high explosives detonation products with explicit polar and ionic species (open access)

Equation of state for high explosives detonation products with explicit polar and ionic species

We introduce a new thermodynamic theory for detonation products that includes polar and ionic species. The new formalism extends the domain of validity of the previously developed EXP6 equation of state library and opens the possibility of new applications. We illustrate the scope of the new approach on PETN detonation properties and water ionization models.
Date: June 28, 2006
Creator: Bastea, S; Glaesemann, K R & Fried, L E
Object Type: Article
System: The UNT Digital Library
Influences of Flow Transients and Porous Medium Heterogeneity on Colloid-Associated Contaminant Transport in the Vadose Zone (open access)

Influences of Flow Transients and Porous Medium Heterogeneity on Colloid-Associated Contaminant Transport in the Vadose Zone

Radionuclides, metals, and dense non-aqueous phase liquids have contaminated about six billion cubic meters of soil at Department of Energy (DOE) sites. The subsurface transport of many of these contaminants is facilitated by colloids (i.e., microscopic, waterborne particles). The first step in the transport of contaminants from their sources to off-site surface water and groundwater is migration through the vadose zone. Developing our understanding of the migration of colloids and colloid-associated contaminants through the vadose zone is critical to assessing and controlling the release of contaminants from DOE sites. In this study, we examined the mobilization, transport, and filtration (retention) of mineral colloids and colloid-associated radionuclides within unsaturated porous media. This investigation involved laboratory column experiments designed to identify properties that affect colloid mobilization and retention and pore-scale visualization experiments designed to elucidate mechanisms that govern these colloid-mass transfer processes. The experiments on colloid mobilization and retention were supplemented with experiments on radionuclide transport through porous media and on radionuclide adsorption to mineral colloids. Observations from all of these experiments – the column and visualization experiments with colloids and the experiments with radionuclides – were used to guide the development of mathematical models appropriate for describing colloids and colloid-facilitated radionuclide …
Date: June 28, 2006
Creator: Saiers, James
Object Type: Report
System: The UNT Digital Library
Measurement of the CKM Angles Gamma And 2 Beta + Gamma at B Factories (open access)

Measurement of the CKM Angles Gamma And 2 Beta + Gamma at B Factories

On behalf of the BABAR and Belle collaborations, the authors report on the measurement of the angle {gamma} and of the sum of angles 2{beta} + {gamma} of the Unitarity Triangle.
Date: June 28, 2006
Creator: Lees, Jean-Pierre
Object Type: Article
System: The UNT Digital Library
Primate-Specific Evolution of an LDLR Enhancer (open access)

Primate-Specific Evolution of an LDLR Enhancer

Sequence changes in regulatory regions have often beeninvoked to explain phenotypic divergence among species, but molecularexamples of this have been difficult to obtain. In this study, weidentified an anthropoid primate specific sequence element thatcontributed to the regulatory evolution of the LDL receptor. Using acombination of close and distant species genomic sequence comparisonscoupled with in vivo and in vitro studies, we show that a functionalcholesterol-sensing sequence motif arose and was fixed within apre-existing enhancer in the common ancestor of anthropoid primates. Ourstudy demonstrates one molecular mechanism by which ancestral mammalianregulatory elements can evolve to perform new functions in the primatelineage leading to human.
Date: June 28, 2006
Creator: Wang, Qian-fei; Prabhakar, Shyam; Wang, Qianben; Moses, Alan M.; Chanan, Sumita; Brown, Myles et al.
Object Type: Article
System: The UNT Digital Library
Super symmetry with Small mu: Connections between Naturalness, Dark Matter, and (Possibly) Flavor (open access)

Super symmetry with Small mu: Connections between Naturalness, Dark Matter, and (Possibly) Flavor

Weak scale supersymmetric theories often suffer from several naturalness problems: the problems of reproducing the correct scale for electroweak symmetry breaking, the correct abundance for dark matter, and small rates for flavor violating processes. We argue that the first two problems point to particular regions of parameter space in models with weak scale supersymmetry: those with a small {mu} term. This has an interesting implication on direct dark matter detection experiments. We find that, if the signs of the three gaugino mass parameters are all equal, we can obtain a solid lower bound on the spin-independent neutralino-nucleon cross section, {sigma}{sub SI}. In the case that the gaugino masses satisfy the unified mass relations, we obtain {sigma}{sub SI} {approx}> 4 x 10{sup -46} cm{sup 2} (1 x 10{sup -46} cm{sup 2}) for fine-tuning in electroweak symmetry breaking no worse than 10% (5%). We also discuss a possibility that the three problems listed above are all connected to the hierarchy of fermion masses. This occurs if supersymmetry breaking and electroweak symmetry breaking (the Higgs fields) are coupled to matter fields with similar hierarchical structures. The discovery of {mu} {yields} e transition processes in near future experiments is predicted in such a framework.
Date: June 28, 2006
Creator: Kitano, Ryuichiro & Nomura, Yasunori
Object Type: Report
System: The UNT Digital Library
Validation and Comparison of One-Dimensional Graound Motion Methodologies (open access)

Validation and Comparison of One-Dimensional Graound Motion Methodologies

Both point- and finite-source stochastic one-dimensional ground motion models, coupled to vertically propagating equivalent-linear shear-wave site response models are validated using an extensive set of strong motion data as part of the Yucca Mountain Project. The validation and comparison exercises are presented entirely in terms of 5% damped pseudo absolute response spectra. The study consists of a quantitative analyses involving modeling nineteen well-recorded earthquakes, M 5.6 to 7.4 at over 600 sites. The sites range in distance from about 1 to about 200 km in the western US (460 km for central-eastern US). In general, this validation demonstrates that the stochastic point- and finite-source models produce accurate predictions of strong ground motions over the range of 0 to 100 km and for magnitudes M 5.0 to 7.4. The stochastic finite-source model appears to be broadband, producing near zero bias from about 0.3 Hz (low frequency limit of the analyses) to the high frequency limit of the data (100 and 25 Hz for response and Fourier amplitude spectra, respectively).
Date: June 28, 2006
Creator: Darragh, B.; Silva, W. & Gregor, N.
Object Type: Report
System: The UNT Digital Library