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China's Top-1000 Energy-Consuming Enterprises Program:Reducing Energy Consumption of the 1000 Largest Industrial Enterprises in China (open access)

China's Top-1000 Energy-Consuming Enterprises Program:Reducing Energy Consumption of the 1000 Largest Industrial Enterprises in China

In 2005, the Chinese government announced an ambitious goal of reducing energy consumption per unit of GDP by 20% between 2005 and 2010. One of the key initiatives for realizing this goal is the Top-1000 Energy-Consuming Enterprises program. The energy consumption of these 1000 enterprises accounted for 33% of national and 47% of industrial energy usage in 2004. Under the Top-1000 program, 2010 energy consumption targets were determined for each enterprise. The objective of this paper is to evaluate the program design and initial results, given limited information and data, in order to understand the possible implications of its success in terms of energy and carbon dioxide emissions reductions and to recommend future program modifications based on international experience with similar target-setting agreement programs. Even though the Top-1000 Program was designed and implemented rapidly, it appears that--depending upon the GDP growth rate--it could contribute to somewhere between approximately 10% and 25% of the savings required to support China's efforts to meet a 20% reduction in energy use per unit of GDP by 2010.
Date: June 2, 2008
Creator: Price, Lynn; Price, Lynn; Wang, Xuejun & Yun, Jiang
Object Type: Report
System: The UNT Digital Library
Ge Interface Engineering with Ozone-oxidation for Low Interface State Density (open access)

Ge Interface Engineering with Ozone-oxidation for Low Interface State Density

Passivation of Ge has been a critical issue for Ge MOS applications in future technology nodes. In this letter, we introduce ozone-oxidation to engineer Ge/insulator interface. Interface states (D{sub it}) values across the bandgap and close to conduction bandedge were extracted using conductance technique at low temperatures. D{sub it} dependency on growth conditions was studied. Minimum D{sub it} of 3 x 10{sup 11} cm{sup -2} V{sup -1} was demonstrated. Physical quality of the interface was investigated through Ge 3d spectra measurements. We found that the interface and D{sub it} is strongly affected by the distribution of oxidation states and quality of the suboxide.
Date: June 2, 2008
Creator: Kuzum, Duygu; Krishnamohan, T.; Pethe, Abhijit J.; Okyay, Ali K.; Oshima, Yasuhiro; Sun, Yun et al.
Object Type: Article
System: The UNT Digital Library
Opportunities for TeV Laser Acceleration (open access)

Opportunities for TeV Laser Acceleration

A set of ballpark parameters for laser, plasma, and accelerator technologies that define for electron energies reaching as high as TeV are identified. These ballpark parameters are carved out from the fundamental scaling laws that govern laser acceleration, theoretically suggested and experimentally explored over a wide range in the recent years. In the density regime on the order of 10{sup 16} cm{sup -3}, the appropriate laser technology, we find, matches well with that of a highly efficient high fluence LD driven Yb ceramic laser. Further, the collective acceleration technique applies to compactify the beam stoppage stage by adopting the beam-plasma wave deceleration, which contributes to significantly enhance the stopping power and energy recovery capability of the beam. Thus we find the confluence of the needed laser acceleration parameters dictated by these scaling laws and the emerging laser technology. This may herald a new technology in the ultrahigh energy frontier.
Date: June 2, 2008
Creator: Kando, M.; Kiriyama, H.; Koga, J. K.; Bulanov, S.; Chao, A. W.; Esirkepov, T. et al.
Object Type: Article
System: The UNT Digital Library
beta 1 integrin inhibition dramatically enhances radiotherapy efficacy in human breast cancer xenografts (open access)

beta 1 integrin inhibition dramatically enhances radiotherapy efficacy in human breast cancer xenografts

{beta}1 integrin signaling has been shown to mediate cellular resistance to apoptosis after exposure to ionizing radiation (IR). Other signaling molecules that increase resistance include Akt, which promotes cell survival downstream of {beta}1 integrin signaling. We showed previously that {beta}1 integrin inhibitory antibodies, AIIB2, enhance apoptosis and decrease growth in human breast cancer cells in 3 dimensional laminin-rich extracellular matrix (3D lrECM) cultures and in vivo. Here we asked whether AIIB2 could synergize with IR to modify Akt-mediated IR resistance. We used 3D lrECM cultures to test the optimal combination of AIIB2 with IR treatment of two breast cancer cell lines, MCF-7 and HMT3522-T4-2, as well as T4-2 myr-Akt breast cancer colonies or HMT3522-S-1, which form normal organotypic structures in 3D lrECM. Colonies were assayed for apoptosis and {beta}1 integrin/Akt signaling pathways were evaluated using western blot. In addition, mice bearing MCF-7 xenografts were used to validate the findings in 3D lrECM. We report that AIIB2 increased apoptosis optimally post-IR by down regulating Akt in breast cancer colonies in 3D lrECM. In vivo, addition of AIIB2 after IR significantly enhanced tumor growth inhibition and apoptosis compared to either treatment alone. Remarkably, the degree of tumor growth inhibition using AIIB2 plus …
Date: June 2, 2008
Creator: Park, Catherine C.; Park, Catherine C.; Zhang, Hui J.; Yao, Evelyn S.; Park, Chong J. & Bissell, Mina J.
Object Type: Article
System: The UNT Digital Library
Deprotection blue in extreme ultraviolet photoresists: influence of base loading and post-exposure bake temperture (open access)

Deprotection blue in extreme ultraviolet photoresists: influence of base loading and post-exposure bake temperture

The deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP5496 extreme ultraviolet photoresists has been determined as their base weight percent is varied. They have also determined the deprotection blur of TOK EUVR P1123 photoresist as the post-exposure bake temperature is varied from 80 C to 120 C. In Rohm and Haas XP 5435 and XP5271 resists 7x and 3x (respective) increases in base weight percent reduce the size of successfully patterned 1:1 line-space features by 16 nm and 8 nm with corresponding reductions in deprotection blur of 7 nm and 4 nm. In XP 5496 a 7x increase in base weight percent reduces the size of successfully patterned 1:1 line-space features from 48 nm to 38 nm without changing deprotection blur. In TOK EUVR P1123 resist, a reduction in post-exposure bake temperature from 100 C to 80 C reduces deprotection blur from 21 nm to 10 nm and reduces patterned LER from 4.8 nm to 4.1 nm.
Date: June 2, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Object Type: Article
System: The UNT Digital Library
Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions (open access)

Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions

This document contains the final report for DOE grant DE-FG02-03ER41239: Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions
Date: June 2, 2008
Creator: Bass, Steffen A.
Object Type: Text
System: The UNT Digital Library
Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam (open access)

Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam

A small set of final prototypes of the ATLAS Inner Detector silicon tracking system(Pixel Detector and SemiConductor Tracker), were used to take data during the 2004 Combined Test Beam. Data were collected from runs with beams of different flavour (electrons, pions, muons and photons) with a momentum range of 2 to 180 GeV/c. Four independent methods were used to align the silicon modules. The corrections obtained were validated using the known momenta of the beam particles and were shown to yield consistent results among the different alignment approaches. From the residual distributions, it is concluded that the precision attained in the alignmentof the silicon modules is of the order of 5 mm in their most precise coordinate.
Date: June 2, 2008
Creator: Ahmad, A.; Andreazza, A.; Atkinson, T.; Baines, J.; Barr, A. J.; Beccherle, R. et al.
Object Type: Article
System: The UNT Digital Library
Field-Analysis of Vacuum Free-Space LaserAcceleration from Rough-Surface and Absorbing Thin Boundaries (open access)

Field-Analysis of Vacuum Free-Space LaserAcceleration from Rough-Surface and Absorbing Thin Boundaries

This script presents a field-based analysis of laser acceleration of relativistic electrons in a free space that is bounded by a thin scattering or by a thin absorbing surface. The laser acceleration process is analyzed in terms of the inverse-radiation formalism and compared to the more familiar field path-integral analysis method. When the scattering boundary is modeled as a linear-index medium the predictions for laser-electron interactions from both field methods are found to agree. For the absorbing boundary both interaction pictures are also found to agree provided that the inverse radiation method is generalized to include absorption of energy from the boundary that is modeled as a linear ohmic-loss object.
Date: June 2, 2008
Creator: Plettner, Thomas & /Stanford U., Ginzton Lab.
Object Type: Article
System: The UNT Digital Library
Connecting Galaxies, Halos, and Star Formation Rates Across Cosmic Time (open access)

Connecting Galaxies, Halos, and Star Formation Rates Across Cosmic Time

A simple, observationally-motivated model is presented for understanding how halo masses, galaxy stellar masses, and star formation rates are related, and how these relations evolve with time. The relation between halo mass and galaxy stellar mass is determined by matching the observed spatial abundance of galaxies to the expected spatial abundance of halos at multiple epochs--i.e. more massive galaxies are assigned to more massive halos at each epoch. This 'abundance matching' technique has been shown previously to reproduce the observed luminosity- and scale-dependence of galaxy clustering over a range of epochs. Halos at different epochs are connected by halo mass accretion histories estimated from N-body simulations. The halo-galaxy connection at fixed epochs in conjunction with the connection between halos across time provides a connection between observed galaxies across time. With approximations for the impact of merging and accretion on the growth of galaxies, one can then directly infer the star formation histories of galaxies as a function of stellar and halo mass. This model is tuned to match both the observed evolution of the stellar mass function and the normalization of the observed star formation rate--stellar mass relation to z {approx} 1. The data demands, for example, that the star …
Date: June 2, 2008
Creator: Conroy, Charlie & Wechsler, Risa H.
Object Type: Article
System: The UNT Digital Library
Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons (open access)

Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons

The authors report measurements of branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup -}, {pi}{sup 0}, {eta} and {eta}{prime}, based on 348 fb{sup -1} of data collected with the BABAR detector, using B{sup 0} and B{sup +} mesons found in the recoil of a second B meson decaying as B {yields} D{sup (*)}{ell}{nu}{sub {ell}}. Assuming isospin symmetry, they combine pionic branching fractions to obtain {Beta}(B{sup 0} {yields} {pi}{sup -} {ell}{sup +} {nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}; they find 3.2{sigma} evidence of the decay B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} and measure its branching fraction to be (0.64 {+-} 0.20{sub (stat)} {+-} 0.3{sub (syst)}) x 10{sup -4}, and determine {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a recent form factor calculation, they obtain the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| = (4.0 {+-} 0.5{sub (stat)} {+-} 0.2{sub (syst){sub -0.5}{sup +0.7}(theory)}) x 10{sup -3}.
Date: June 2, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
XPD Helicase Structures and Activities: Insights into the Cancer and Aging Phenotypes from XPD Mutations (open access)

XPD Helicase Structures and Activities: Insights into the Cancer and Aging Phenotypes from XPD Mutations

Mutations in XPD helicase, required for nucleotide excision repair (NER) as part of the transcription/repair complex TFIIH, cause three distinct phenotypes: cancer-prone xeroderma pigmentosum (XP), or aging disorders Cockayne syndrome (CS), and trichothiodystrophy (TTD). To clarify molecular differences underlying these diseases, we determined crystal structures of the XPD catalytic core from Sulfolobus acidocaldarius and measured mutant enzyme activities. Substrate-binding grooves separate adjacent Rad51/RecA-like helicase domains (HD1, HD2) and an arch formed by 4FeS and Arch domains. XP mutations map along the HD1 ATP-binding edge and HD2 DNA-binding channel and impair helicase activity essential for NER. XP/CS mutations both impair helicase activity and likely affect HD2 functional movement. TTD mutants lose or retain helicase activity but map to sites in all four domains expected to cause framework defects impacting TFIIH integrity. These results provide a foundation for understanding disease consequences of mutations in XPD and related 4Fe-4S helicases including FancJ.
Date: June 2, 2008
Creator: Tainer, John; Fan, Li; Fuss, Jill O.; Cheng, Quen J.; Arvai, Andrew S.; Hammel, Michal et al.
Object Type: Article
System: The UNT Digital Library
Probabilistic consequence model of accidenal or intentional chemical releases. (open access)

Probabilistic consequence model of accidenal or intentional chemical releases.

In this work, general methodologies for evaluating the impacts of large-scale toxic chemical releases are proposed. The potential numbers of injuries and fatalities, the numbers of hospital beds, and the geographical areas rendered unusable during and some time after the occurrence and passage of a toxic plume are estimated on a probabilistic basis. To arrive at these estimates, historical accidental release data, maximum stored volumes, and meteorological data were used as inputs into the SLAB accidental chemical release model. Toxic gas footprints from the model were overlaid onto detailed population and hospital distribution data for a given region to estimate potential impacts. Output results are in the form of a generic statistical distribution of injuries and fatalities associated with specific toxic chemicals and regions of the United States. In addition, indoor hazards were estimated, so the model can provide contingency plans for either shelter-in-place or evacuation when an accident occurs. The stochastic distributions of injuries and fatalities are being used in a U.S. Department of Homeland Security-sponsored decision support system as source terms for a Monte Carlo simulation that evaluates potential measures for mitigating terrorist threats. This information can also be used to support the formulation of evacuation plans and …
Date: June 2, 2008
Creator: Chang, Y.-S.; Samsa, M. E.; Folga, S. M. & Hartmann, H. M.
Object Type: Report
System: The UNT Digital Library
Production and Characterization of Attosecond Bunch Trains (open access)

Production and Characterization of Attosecond Bunch Trains

We report the production of optically spaced attosecond microbunches produced by the inverse Free Electron Laser (IFEL) process. The IFEL is driven by a Ti:sapphire laser synchronized with the electron beam. The IFEL is followed by a magnetic chicane that converts the energy modulation into the longitudinal microbunch structure. The microbunch train is characterized by observing Coherent Optical Transition Radiation (COTR) at multiple harmonics of the bunching. The experimental results are compared with 1D analytic theory showing good agreement. Estimates of the bunching factors are given and correspond to a microbunch length of 350as fwhm. The formation of stable attosecond electron pulse trains marks an important step towards direct laser acceleration.
Date: June 2, 2008
Creator: Sears, Christopher M. S.; Colby, Eric; Ischebeck, Rasmus; McGuinness , Christopher; Nelson, Janice; Noble, Robert et al.
Object Type: Article
System: The UNT Digital Library
Climate Change: Design Approaches for a Greenhouse Gas Reduction Program (open access)

Climate Change: Design Approaches for a Greenhouse Gas Reduction Program

This report explores strategies to control greenhouse gas (GHG) emissions and options to address the cost issue in four parts. First, the basic economic tradeoff between controlling the quantity of GHG emissions and the program's compliance costs is introduced and explained. Second, the five dimensions of the cost issue that have arisen so far in the climate change debate are identified and discussed. Third, a representative sample of proposed approaches to address cost concerns is compared and analyzed according to the five cost dimensions identified previously. Finally, the proposed options are summarized and opportunities to combine or merge different approaches are analyzed.
Date: June 2, 2008
Creator: Parker, Larry
Object Type: Report
System: The UNT Digital Library
Emission Allowance Allocation in a Cap-and-Trade Program: Options and Considerations (open access)

Emission Allowance Allocation in a Cap-and-Trade Program: Options and Considerations

The first two sections of this report discuss the primary emission allowance distribution methods: auctions and no-cost distribution to covered sources. These sections examine the potential benefits and concerns of these allocation mechanisms. The final section identifies different options and policy considerations for Congress when determining to whom and for what purpose to distribute the value of the emission allowances.
Date: June 2, 2008
Creator: Ramseur, Jonathan L.
Object Type: Report
System: The UNT Digital Library
Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses (open access)

Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses

This report focuses on options for protecting structures and for protecting wildlands and natural resources from wildfires. It begins with a brief overview of the nature of wildfires, followed by a discussion of protecting structures. Then, it discusses wildfire damages to wildlands and natural resources, fuel treatment options and their benefits and limitations, and public involvement in federal decisions.
Date: June 2, 2008
Creator: Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
United States Fire Administration: An Overview (open access)

United States Fire Administration: An Overview

The report discusses the U.S. Fire Administration (USFA), which is an entity within the Federal Emergency Management Agency (FEMA) of the Department of Homeland Security (DHS).
Date: June 2, 2008
Creator: Kruger, Lennard G.
Object Type: Report
System: The UNT Digital Library
Aqueous Ln(III) Luminescence Agents Derived from a Tasty Precursor (open access)

Aqueous Ln(III) Luminescence Agents Derived from a Tasty Precursor

The synthesis, aqueous stability and photophysical properties are reported for a novel tetradentate ligand derived from maltol, a commonly used flavor enhancer. In aqueous solution, this chelate forms stable complexes with Ln(III) cations, and sensitized emission was observed from Eu(III), Yb(III), and Nd(III). A comparison with recently reported and structurally analogous ligands reveals a slightly higher basicity but lower complex stability with Eu(III) [pEu = 14.7 (1)]. A very poor metal centered quantum yield with Eu(III) was observed ({Phi}{sub tot} = 0.04%), which can be rationalized by the similar energy of the ligand triplet state and the Eu(III) {sup 5}D{sub 0} emissive level. Instead, sensitized emission from the Yb(III) and Nd(III) cations was observed, which emit in the Near Infra-Red (NIR).
Date: June 2, 2008
Creator: Jocher, C. J.; Moore, E. G.; Pierce, J. D. & Raymond, K. N.
Object Type: Article
System: The UNT Digital Library
Don't always blame the photons: Relationships between deprotection blur, LER, and shot noise in EUV photoresists (open access)

Don't always blame the photons: Relationships between deprotection blur, LER, and shot noise in EUV photoresists

A corner rounding metric has been used to determine the deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP 5496 extreme ultraviolet (EUV) photoresists as base weight percent is varied; an experimental open platform photoresist (EH27) as base weight percent is varied; and TOK EUVR P1123 and FUJI 1195 photoresists as post-exposure bake (PEB) temperature is varied. In the XP 5435, XP 5271, XP 5496, and EH27 resist platforms, a 6 times increase in base weight percent reduces the size of successfully patterned 1:1 lines by over 10 nm and lowers intrinsic line-edge roughness (LER) by over 2.5 nm without changing deprotection blur. In TOK EUVR P1123 photoresist, lowering the PEB temperature from 100 C to 80 C reduces measured deprotection blur (using the corner metric) from 30 nm to 20 nm and reduces the LER of 50 nm 1:1 lines from 4.8 nm to 4.3 nm. These data are used to drive a lengthy discussion about the relationships between deprotection blur, LER, and shot noise in EUV photoresists. We provide two separate conclusions: (1) shot noise is probably not the dominant mechanism causing the 3-4 nm EUV LER floor that has been observed over the past …
Date: June 2, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Object Type: Article
System: The UNT Digital Library
INITIAL EVALUATION OF A PULSED WHITE SPECTRUM NEUTRON GENERATOR FOR EXPLOSIVE DETECTION (open access)

INITIAL EVALUATION OF A PULSED WHITE SPECTRUM NEUTRON GENERATOR FOR EXPLOSIVE DETECTION

Successful explosive material detection in luggage and similar sized containers is acritical issue in securing the safety of all airline passengers. Tensor Technology Inc. has recently developed a methodology that will detect explosive compounds with pulsed fast neutron transmission spectroscopy. In this scheme, tritium beams will be used to generate neutrons with a broad energy spectrum as governed by the T(t,2n)4He fission reaction that produces 0-9 MeV neutrons. Lawrence Berkeley National Laboratory (LBNL), in collaboration with Tensor Technology Inc., has designedand fabricated a pulsed white-spectrum neutron source for this application. The specifications of the neutron source are demanding and stringent due to the requirements of high yield and fast pulsing neutron emission, and sealed tube, tritium operation. In a unique co-axial geometry, the ion source uses ten parallel rf induction antennas to externally couple power into a toroidal discharge chamber. There are 20 ion beam extraction slits and 3 concentric electrode rings to shape and accelerate the ion beam into a titanium cone target. Fast neutron pulses are created by using a set ofparallel-plate deflectors switching between +-1500 volts and deflecting the ion beams across a narrow slit. The generator is expected to achieve 5 ns neutron pulses at tritium …
Date: June 2, 2008
Creator: King, Michael J.; Miller, Gill T.; Reijonen, Jani; Ji, Qing; Andresen, Nord; Gicquel,, Frederic et al.
Object Type: Article
System: The UNT Digital Library

Synthesis and Chemistry of Polyfunctionalized Cyclohexasilanes

None
Date: June 2, 2008
Creator: Boudjouk, Philip; Kim, Beon-Kyu; Choi, Seok-Bong; Dai, Xuliang; Pokhodnya, Kostantin; Nelson, Kendric et al.
Object Type: Presentation
System: The UNT Digital Library
The Role of Offsets in a Greenhouse Gas Emissions Cap-and-Trade Program: Potential Benefits and Concerns (open access)

The Role of Offsets in a Greenhouse Gas Emissions Cap-and-Trade Program: Potential Benefits and Concerns

This report discusses offsets in relation to a greenhouse gas emissions cap-and-trade program. The first section of this report provides an overview of offsets by discussing different types of offset projects and describing how the offsets would likely be used in an emission reduction program. The next section discusses the supply of offsets that might be available in an emission trading program. The subsequent sections examine the potential offset benefits and the potential concerns associated with offsets. The final section offers considerations for Congress.
Date: June 2, 2008
Creator: Ramseur, Jonathan L.
Object Type: Report
System: The UNT Digital Library
Safeguarding the Nation's Drinking Water: EPA and Congressional Actions (open access)

Safeguarding the Nation's Drinking Water: EPA and Congressional Actions

This report discusses the Environmental Protection Agency's (EPA) efforts to increase drinking water security, Bioterrorism Preparedness and Response Act of 2002, and EPA and Department of Homeland Security (DHS) water infrastructure security roles.
Date: June 2, 2008
Creator: Tiemann, Mary
Object Type: Report
System: The UNT Digital Library
Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses (open access)

Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses

This report focuses on options for protecting structures, wildlands, and natural resources from wildfires. It begins with a brief overview of the nature of wildfires, followed by a discussion of protecting structures. Then it discusses wildfire damages to wildlands and natural resources; fuel treatment options and their benefits and limitations; and public involvement in federal decisions.
Date: June 2, 2008
Creator: Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library