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Benchmarking and Self-Assessment in the Wine Industry (open access)

Benchmarking and Self-Assessment in the Wine Industry

Not all industrial facilities have the staff or theopportunity to perform a detailed audit of their operations. The lack ofknowledge of energy efficiency opportunities provides an importantbarrier to improving efficiency. Benchmarking programs in the U.S. andabroad have shown to improve knowledge of the energy performance ofindustrial facilities and buildings and to fuel energy managementpractices. Benchmarking provides a fair way to compare the energyintensity of plants, while accounting for structural differences (e.g.,the mix of products produced, climate conditions) between differentfacilities. In California, the winemaking industry is not only one of theeconomic pillars of the economy; it is also a large energy consumer, witha considerable potential for energy-efficiency improvement. LawrenceBerkeley National Laboratory and Fetzer Vineyards developed the firstbenchmarking tool for the California wine industry called "BEST(Benchmarking and Energy and water Savings Tool) Winery". BEST Wineryenables a winery to compare its energy efficiency to a best practicereference winery. Besides overall performance, the tool enables the userto evaluate the impact of implementing efficiency measures. The toolfacilitates strategic planning of efficiency measures, based on theestimated impact of the measures, their costs and savings. The tool willraise awareness of current energy intensities and offer an efficient wayto evaluate the impact of future efficiency measures.
Date: December 1, 2005
Creator: Galitsky, Christina; Radspieler, Anthony; Worrell, Ernst; Healy,Patrick & Zechiel, Susanne
System: The UNT Digital Library
Double Gap Alfvén Eigenmodes: Revisiting Eigenmodes Interaction with the Alfvén Continuum (open access)

Double Gap Alfvén Eigenmodes: Revisiting Eigenmodes Interaction with the Alfvén Continuum

A new type of global shear Alfvén Eigenmode is found in tokamak plasmas where the mode localization is in the region intersecting the Alfvén continuum. The eigenmode is formed by the coupling of two solutions from two adjacent gaps (akin to potential wells) in the shear Alfvén continuum. For tokamak plasmas with reversed magnetic shear it is shown that the toroidiciy-induced solution tunnels through the continuum to match the ellipticity-induced Alfvén eigenmode (TAE and EAE, respectively) so that the resulting solution is continuous at the point of resonance with the continuum. The existence of these Double Gap Alfvén Eigenmodes (DGAEs) allows for potentially new ways of coupling edge fields to the plasma core in conditions where the core region is conventionally considered inaccessible. Implications include new approaches to heating and current drive in fusion plasmas as well as its possible use as core diagnostic in burning plasmas.
Date: December 1, 2005
Creator: Gorelenkov, N. N.
System: The UNT Digital Library
Ion-Optics Calculations and Preliminary Precision Estimates of the Gas-Capable Ion Source for the 1-MV LLNL BioAMS Spectrometer (open access)

Ion-Optics Calculations and Preliminary Precision Estimates of the Gas-Capable Ion Source for the 1-MV LLNL BioAMS Spectrometer

Ion-optics calculations were performed for a new ion source and injection beam line. This source, which can accept both solid and gaseous targets, will be installed onto the 1-MV BioAMS spectrometer at the Center for Accelerator Mass Spectrometry, located at Lawrence Livermore National Laboratory and will augment the current LLNL cesium-sputter solid sample ion source. The ion source and its associated injection beam line were designed to allow direct quantification of {sup 14}C/{sup 12}C and {sup 3}H/{sup 1}H isotope ratios from both solid and gaseous targets without the need for isotope switching. Once installed, this source will enable the direct linking of a nanoflow LC system to the spectrometer to provide for high-throughput LC-AMS quantitation from a continuous flow. Calculations show that, for small samples, the sensitivity of the gas-accepting ion source could be precision limited but zeptomole quantitation should be feasible.
Date: December 13, 2005
Creator: Ognibene, T. J.; Bench, G.; Brown, T. A. & Vogel, J. S.
System: The UNT Digital Library
Effects of Overhangs on the Performance of ElectrochromicWindows (open access)

Effects of Overhangs on the Performance of ElectrochromicWindows

None
Date: December 1, 2005
Creator: Tavil, Aslihan & Lee, Eleanor S.
System: The UNT Digital Library
An Extensible Open-Source Compiler Infrastructure for Testing (open access)

An Extensible Open-Source Compiler Infrastructure for Testing

Testing forms a critical part of the development process for large-scale software, and there is growing need for automated tools that can read, represent, analyze, and transform the application's source code to help carry out testing tasks. However, the support required to compile applications written in common general purpose languages is generally inaccessible to the testing research community. In this paper, we report on an extensible, open-source compiler infrastructure called ROSE, which is currently in development at Lawrence Livermore National Laboratory. ROSE specifically targets developers who wish to build source-based tools that implement customized analyses and optimizations for large-scale C, C++, and Fortran90 scientific computing applications (on the order of a million lines of code or more). However, much of this infrastructure can also be used to address problems in testing, and ROSE is by design broadly accessible to those without a formal compiler background. This paper details the interactions between testing of applications and the ways in which compiler technology can aid in the understanding of those applications. We emphasize the particular aspects of ROSE, such as support for the general analysis of whole programs, that are particularly well-suited to the testing research community and the scale of the …
Date: December 9, 2005
Creator: Quinlan, D; Ur, S & Vuduc, R
System: The UNT Digital Library
Bell-Plesset effects for an accelerating interface with contiguous density gradients (open access)

Bell-Plesset effects for an accelerating interface with contiguous density gradients

A Plesset-type treatment [J. Appl. Phys. 25, 96 (1954)] is used to assess the effects of contiguous density gradients at an accelerating spherical classical interface on Rayleigh-Taylor and Bell-Plesset perturbation growth. Analytic expressions are obtained that describe enhanced Rayleigh-Taylor instability growth from contiguous density gradients aligned with the acceleration and which increase the effective Atwood number of the perturbed interface. A new pathway for geometric amplification of surface perturbations on an accelerating interface with contiguous density gradients is identified. A resonance condition between the density-gradient scalelength and the radius of the interface is also predicted based on a linearized analysis of Bernoulli's equation, potentially leading to enhanced perturbation growth. Comparison of the analytic treatment with detailed two-dimensional single-mode growth-factor simulations shows good agreement for low-mode numbers where the effects of spherical geometry are most manifested.
Date: December 20, 2005
Creator: Amendt, P
System: The UNT Digital Library
Scaling, Microstructure and Dynamic Fracture (open access)

Scaling, Microstructure and Dynamic Fracture

The relationship between pullback velocity and impact velocity is studied for different microstructures in Cu. A size distribution of potential nucleation sites is derived under the conditions of an applied stochastic stress field. The size distribution depends on flow stress leading to a connection between the plastic flow appropriate to a given microstructure and nucleation rate. The pullback velocity in turn depends on the nucleation rate resulting in a prediction for the relationship between pullback velocity and flow stress. The theory is compared to observations of Cu on Cu gas-gun experiments (10-50 GPa) for a diverse set of microstructures. The scaling law is incorporated into a 1D finite difference code and is shown to reproduce the experimental data with one adjustable parameter that depends only on a nucleation exponent, {Lambda}.
Date: December 21, 2005
Creator: Minich, R W; Kumar, M; Schwarz, A & Cazamias, J
System: The UNT Digital Library
U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers (open access)

U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers

Both chemical weathering rates and fluid flow are difficultto measure in natural systems. However, these parameters are critical forunderstanding the hydrochemical evolution of aquifers, predicting thefate and transport of contaminants, and for water resources/water qualityconsiderations. 87Sr/86Sr and (234U/238U) activity ratios are sensitiveindicators of water-rock interaction, and thus provide a means ofquantifying both flow and reactivity. The 87Sr/86Sr values in groundwaters are controlled by the ratio of the dissolution rate to the flowrate. Similarly, the (234U/238U) ratio of natural ground waters is abalance between the flow rate and the dissolution of solids, andalpha-recoil loss of 234U from the solids. By coupling these two isotopesystems it is possible to constrain both the long-term (ca. 100's to1000's of years) flow rate and bulk dissolution rate along the flow path.Previous estimates of the ratio of the dissolution rate to theinfiltration flux from Sr isotopes (87Sr/86Sr) are combined with a modelfor (234U/238U) to constrain the infiltration flux and dissolution ratefor a 70-m deep vadose zone core from Hanford, Washington. The coupledmodel for both (234U/238U) ratios and the 87Sr/86Sr data suggests aninfiltration flux of 5+-2 mm/yr, and bulk silicate dissolution ratesbetween 10-15.7 and 10-16.5 mol/m2/s. The process of alpha-recoilenrichment, while primarily responsible for the observed variation …
Date: December 27, 2005
Creator: Maher, Kate; DePaolo, Donald J. & Christensen, John N.
System: The UNT Digital Library
A Chemical Approach to 3-D Lithographic Patterning of Si and GeNanocrystals (open access)

A Chemical Approach to 3-D Lithographic Patterning of Si and GeNanocrystals

Ion implantation into silica followed by thermal annealingis an established growth method for Si and Ge nanocrystals. Wedemonstrate that growth of Group IV semiconductor nanocrystals can besuppressed by co-implantation of oxygen prior to annealing. For Sinanocrystals, at low Si/O dose ratios, oxygen co-implantation leads to areduction of the average nanocrystal size and a blue-shift of thephotoluminescence emission energy. For both Si and Ge nanocrystals, atlarger Si/O or Ge/O dose ratios, the implanted specie is oxidized andnanocrystals do not form. This chemical deactivation was utilized toachieve patterned growth of Si and Ge nanocrystals. Si was implanted intoa thin SiO2 film on a Si substrate followed by oxygen implantationthrough an electron beam lithographically defined stencil mask. Thermalannealing of the co-implanted structure yields two-dimensionallypatterned growth of Si nanocrystals under the masked regions. We applieda previously developed process to obtain exposed nanocrystals byselective HF etching of the silica matrix to these patterned structures.Atomic force microscopy (AFM) of etched structures revealed that exposednanocrystals are not laterally displaced from their original positionsduring the etching process. Therefore, this process provides a means ofachieving patterned structures of exposed nanocrystals. The possibilitiesfor scaling this chemical-based lithography process to smaller featuresand for extending it to 3-D patterning is discussed.
Date: December 12, 2005
Creator: Sharp, I. D.; Xu, Q.; Yi, D. O.; Liao, C. Y.; Ager, J. W., III; Beeman, J. W. et al.
System: The UNT Digital Library
HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS (open access)

HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS

We present experimental data of electron energy distributions from ultra-intense (>10{sup 19} W/cm{sup 2}) laser-solid interactions using the Rutherford Appleton Laboratory Vulcan petawatt laser. These measurements were made using a CCD-based magnetic spectrometer. We present details on the distinct effective temperatures that were obtained for a wide variety of targets as a function of laser intensity. It is found that as the intensity increases from 10{sup 17} W/cm{sup 2} to 10{sup 19} W/cm{sup 2}, a 0.4 dependence on the laser intensity is found. Between 10{sup 19} W/cm{sup 2} and 10{sup 20} W/cm{sup 2}, a gradual rolling off of temperature with intensity is observed.
Date: December 8, 2005
Creator: Chen, H; Wilks, S C; Kruer, W L; Moon, S; Patel, N; Patel, P K et al.
System: The UNT Digital Library
Search for H ---> b anti-b produced in association with W bosons in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for H ---> b anti-b produced in association with W bosons in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors present a search for the standard model Higgs boson decaying into b{bar b} and produced in association with W bosons in p{bar p} collisions at {radical}s = 1.96 TeV. This search uses 320 pb{sup -1} of the dataset accumulated by the upgraded Collider Detector at Fermilab. Events are selected that have a high-transverse momentum electron or muon, missing transverse energy, and two jets, at least one of which is consistent with the hadronization of a b quark. Both the number of events and the dijet mass distribution are consistent with standard model background expectations, and they set 95% confidence level upper limits on the production cross section times branching ratio for the Higgs boson or any new particle with similar decay kinematics. These upper limits range from 10 pb for m{sub H} = 110 GeV/c{sup 2} to 3 pb for m{sub H} = 150 GeV/c{sup 2}.
Date: December 1, 2005
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, Anthony A.; Akimoto, T.; Albrow, M.G. et al.
System: The UNT Digital Library
CONSIDERATIONS OF THE ROLE OF THE CATHODIC REGION IN LOCALIZED CORROSION (open access)

CONSIDERATIONS OF THE ROLE OF THE CATHODIC REGION IN LOCALIZED CORROSION

None
Date: December 19, 2005
Creator: KELLY, R.G., LANDAU, U., PAYER, J.H.
System: The UNT Digital Library
Evidence for p-type doping of InN (open access)

Evidence for p-type doping of InN

None
Date: December 21, 2005
Creator: Jones, R. E.; Yu, K. M.; Li, S. X.; Walukiewicz, W.; Ager, J. W., III; Haller, E. E. et al.
System: The UNT Digital Library
Evidence for Groundwater Contamination Vulnerability in California?s Central Valley (open access)

Evidence for Groundwater Contamination Vulnerability in California?s Central Valley

The California Water Resources Control Board, in collaboration with the US Geological Survey and Lawrence Livermore National Laboratory, has implemented a program to assess the susceptibility of groundwater resources. Advanced techniques such as groundwater age dating using the tritium-helium method, extensive use of oxygen isotopes of the water molecule ({delta}{sup 18}O) for recharge water provenance, and analysis of common volatile organic compounds (VOCs) at ultra-low levels are applied with the goal of assessing the contamination vulnerability of deep aquifers, which are frequently used for public drinking water supply. Over 1200 public drinking water wells have been tested to date, resulting in a very large, tightly spaced collection of groundwater ages in some of the heavily exploited groundwater basins of California. Smaller scale field studies that include shallow monitoring wells are aimed at assessing the probability that nitrate will be transported to deep drinking water aquifers. When employed on a basin-scale, groundwater ages are an effective tool for identifying recharge areas, defining flowpaths, and determining the rate of transport of water and entrained contaminants. De-convolution of mixed ages, using ancillary dissolved noble gas data, gives insight into the water age distribution drawn at a well, and into the effective dilution of …
Date: December 13, 2005
Creator: Moran, J. E.; Leif, R.; Esser, B. K. & Singleton, M. J.
System: The UNT Digital Library
Modeling An atmospheric Release As An Area Source In Support Of Waste Disposal At The Savannah River Site (open access)

Modeling An atmospheric Release As An Area Source In Support Of Waste Disposal At The Savannah River Site

None
Date: December 6, 2005
Creator: SIMPKINS, ALI
System: The UNT Digital Library
On the Micromechanisms of Shock-Induced Martensitic Transformation in Tantalum (open access)

On the Micromechanisms of Shock-Induced Martensitic Transformation in Tantalum

Shock-induced twinning and martensitic transformation in tantalum, which exhibits no solid-state phase transformation under hydrostatic pressures up to 100 GPa, have been further investigated. Since the volume fraction and size of twin and phase domains are small in scale, they are considered foming by heterogeneous nucleation that is catalyzed by high density lattice dislocations. A dynamic dislocation mechanism is accordingly proposed based upon the observation of dense dislocation clustering within shock-recovered tantalum. The dense dislocation clustering can cause a significant increase of strain energy in local regions of {beta} (bcc) matrix, which renders mechanical instability and initiates the nucleation of twin and phase domains through the spontaneous reactions of dislocation dissociation within the dislocation clusters. That is, twin domains can be nucleated within the clusters through the homogeneous dissociation of 1/2<111> dislocations into 1/6<111> partial dislocations, and {omega} phase domains can be nucleated within the closters through the inhomogeneous dissociation of 1/2<111> dislocations into 1/12<111>, 1/3<111> and 1/12<111> partial dislocations.
Date: December 7, 2005
Creator: Hsiung, L L
System: The UNT Digital Library
A Strong Hot Spot Theorem (open access)

A Strong Hot Spot Theorem

A real number alpha is said to be b-normal if every m-long string of digits appears in the base-b expansion of alpha with limiting frequency b-m. We prove that alpha is b-normal if and only if it possesses no base-b ''hot spot''. In other words, alpha is b-normal if and only if there is no real number y such that smaller and smaller neighborhoods of y are visited by the successive shifts of the base-b expansion of alpha with larger and larger frequencies, relative to the lengths of these neighborhoods
Date: December 31, 2005
Creator: Bailey, David H. & Misiurewicz, Michal
System: The UNT Digital Library
Reactive Spreading of a Lead-Free Solder on Alumina (open access)

Reactive Spreading of a Lead-Free Solder on Alumina

The wetting of Sn3Ag-based alloys on Al{sub 2}O{sub 3} has been studied using the sessile-drop configuration. Small additions of Ti decrease the contact angle of Sn3Ag alloys on alumina from 115 to 23 degrees. Adsorption of Ti-species at the solid-liquid interface prior to reaction is the driving force for the observed decrease in contact angle, and the spreading kinetics is controlled by the kinetics of Ti dissolution into the molten alloy. The addition of Ti increases the transport rates at the solid-liquid interface, resulting in the formation of triple-line ridges that pin the liquid front and promote a wide variability in the final contact angles.
Date: December 1, 2005
Creator: Gremillard, L.; Saiz, E.; Radmilovic, V.R. & Tomsia, A.P.
System: The UNT Digital Library
On the Equivalence of Nonnegative Matrix Factorization and K-means- Spectral Clustering (open access)

On the Equivalence of Nonnegative Matrix Factorization and K-means- Spectral Clustering

We provide a systematic analysis of nonnegative matrix factorization (NMF) relating to data clustering. We generalize the usual X = FG{sup T} decomposition to the symmetric W = HH{sup T} and W = HSH{sup T} decompositions. We show that (1) W = HH{sup T} is equivalent to Kernel K-means clustering and the Laplacian-based spectral clustering. (2) X = FG{sup T} is equivalent to simultaneous clustering of rows and columns of a bipartite graph. We emphasizes the importance of orthogonality in NMF and soft clustering nature of NMF. These results are verified with experiments on face images and newsgroups.
Date: December 4, 2005
Creator: Ding, Chris; He, Xiaofeng; Simon, Horst D. & Jin, Rong
System: The UNT Digital Library
Using Ice to Mimic Nacre: From Structural Materials to ArtificialBone (open access)

Using Ice to Mimic Nacre: From Structural Materials to ArtificialBone

None
Date: December 1, 2005
Creator: Deville, Sylvain; Saiz, Eduardo; Nalla, Ravi K. & Tomsia, Antoni P.
System: The UNT Digital Library
Controlled Fusion with Hot-ion Mode in a Degenerate Plasma (open access)

Controlled Fusion with Hot-ion Mode in a Degenerate Plasma

n a Fermi-degenerate plasma, the rate of electron physical processes is much reduced from the classical prediction, possibly enabling new regimes for controlled nuclear fusion, including the hot-ion mode, a regime in which the ion temperature exceeds the electron temperature. Previous calculations of these processes in dense plasmas are now corrected for partial degeneracy and relativistic effects, leading to an expanded regime of self-sustained fusion.
Date: December 1, 2005
Creator: Fisch, S. Son and N.J.
System: The UNT Digital Library
Dynamic Stark Effect and Forbidden-Transition Spectral Lineshapes (open access)

Dynamic Stark Effect and Forbidden-Transition Spectral Lineshapes

We report on an experimental and theoretical study of thedynamic (ac) Stark effect on a for bidden transition. A general frameworkfor parameterizing and describing off-resonant ac-Stark shifts ispresented. A model is developed to calculate spectral line shapesresulting from resonant excitation of atoms in an intense standinglight-wave in the presence of off-resonant ac-Stark shifts. The model isused in the analysis and interpretation of a measurement of the ac-Starkshifts of the static-electric-field-induced 6s2 1S0 -->5d6s 3D1transition at 408 nm in atomic Yb. The results are in agreement withestimates of the ac-Stark shift of the transition under the assumptionthat the shift is dominated by that of the 6s2 1S0 ground state. Adetailed description of the experiment and analysis is presented. Abi-product of this work is an ind ependent determination (from thesaturation behavior of the 408-nm transition) of the Stark transitionpolarizability, which is found to be in agreement with our earliermeasurement. This work is part of the ongoing effort aimed at a precisionmeasurement of atomic parity-violation effects in Yb.
Date: December 15, 2005
Creator: Stalnaker, Jason E.; Budker, D.; Freedman, S. J.; Guzman, J. S.; Rochester, S. M. & Yashchuk, V. V.
System: The UNT Digital Library
Electronic interactions between gold nanoclusters in constrainedgeometries (open access)

Electronic interactions between gold nanoclusters in constrainedgeometries

None
Date: December 9, 2005
Creator: Kim, Sang Hoon; Hwang, S.; Shon, Young-Seok; Ogletree, D. Frank & Salmeron, Miquel
System: The UNT Digital Library
Coordination Complexes of Decamethylytterbocene with4,4'-Disubstituted Bipyridines: An Experimental Study of Spin Coupling inLanthanide Complexes (open access)

Coordination Complexes of Decamethylytterbocene with4,4'-Disubstituted Bipyridines: An Experimental Study of Spin Coupling inLanthanide Complexes

The paramagnetic 1:1 coordination complexes of (C5Me5)2Ybwith a series of 4,4'-disubstituted bipyridines, bipy-X, where X is Me,tert-Bu, OMe, Ph, CO2Me, and CO2Et have been prepared. All of thecomplexes are paramagnetic and the values of the magnetic susceptibilityas a function of temperature show that these values are less thanexpected for the cation, [(C5Me5)2Yb(III)(bipy-X)]+, which have beenisolated as the cation-anion ion-pairs[(C5Me5)2Yb(III)(bipy-X)]+[(C5Me5)2YbI2]f fnfn where X is CO2Et, OMe andMe. The 1H NMR chemical shifts (293 K) for the methine resonances locatedat the 6,6' site in the bipy-X ring show a linear relationship with thevalues of chiT (300 K) for the neutral complexes which illustrates thatthe molecular behavior does not depend upon the phase with one exception,viz., (C5Me5)2Yb(bipy-Me). Single crystals of the 4,4'-dimethylbipyridinecomplex undergo an irreversible, abrupt first order phase change at 228 Kthat shatters the single crystals. The magnetic susceptibility,represented in a delta vs. T plot, on this complex, in polycrystallineform undergoes reversible abrupt changes in the temperature regime 205 -212 K, which is suggested to be due to the way the individual molec ularunits pack in the unit cell. A qualitative model is proposed thataccounts for the sub-normal magnetic moments in theseytterbocene-bipyridine complexes.
Date: December 8, 2005
Creator: Walter, Marc D.; Berg, David J. & Andersen, Richard A.
System: The UNT Digital Library