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Black carbon emissions in the United Kingdom during the past four decades: An empirical analysis (open access)

Black carbon emissions in the United Kingdom during the past four decades: An empirical analysis

We use data from a unique 40-year record of 150 urban and rural stations in the ''Black Smoke and SO2 Network'' in Great Britain to infer information about sources of atmospheric black carbon (BC). The data show a rapid decline of ambient atmospheric BC between 1962 and the early 1990s that exceeds the decline in official estimates of BC emissions based only on amount of fuel use and mostly fixed emission factors. This provides empirical confirmation of the existence and large impact of a time-dependent ''technology factor'' that must multiply the rate of fossil fuel use. Current ambient BC amounts in Great Britain comparable to those in western and central Europe, with diesel engines being the principal present source. From comparison of BC and SO2 data we infer that current BC emission inventories understate true emissions in the U.K. by about a factor of two. The results imply that there is the potential for improved technology to achieve large reduction of global ambient BC. There is a need for comparable monitoring of BC in other countries.
Date: April 22, 2004
Creator: Novakov, T. & Hansen, J.E.
System: The UNT Digital Library
Black ring deconstruction (open access)

Black ring deconstruction

We present a sample microstate for a black ring in four and five dimensional language. The microstate consists of a black string microstate with an additional D6-brane. We show that with an appropriate choice of parameters the piece involving the black string microstate falls down a long AdS throat, whose M-theory lift is AdS_3 x S2. We wrap a spinning dipole M2-brane on the S2 in the probe approximation. In IIA, this corresponds to a dielectric D2-brane carrying only D0-charge. We conjecture this is the firstapproximation to a cloud of D0-branes blowing up due to their non-abelian degrees of freedom and the Myers effect.
Date: June 22, 2007
Creator: Gimon, Eric; Gimon, Eric G. & Levi, Thomas S.
System: The UNT Digital Library
Booster Gold Beam Injection Efficiency and Beam Loss (open access)

Booster Gold Beam Injection Efficiency and Beam Loss

The Relativistic Heavy Ion Collider (RHIC) at the BNL requires the AGS to provide Gold beam with the intensity of 10{sup 9} ions per bunch. Over the years, the Tandem Van de Graaff has provided steadily increasing intensity of gold ion beams to the AGS Booster. However, the gold beam injection efficiency at the Booster has been found to decrease with the rising intensity of injected beams. As the result, for Tandem beams of the highest intensity, the Booster late intensity is lower than with slightly lower intensity Tandem beam. In this article, the authors present two experiments associated with the Booster injection efficiency and beam intensity. One experiment looks at the Booster injection efficiency by adjusting the Tandem beam intensity, and another looks at the beam life time while scraping the beam in the Booster. The studies suggest that the gold beam injection efficiency at the AGS Booster is related to the beam loss in the ring, rather than the intensity of injected beam or circulating beam. A close look at the effect of the lost gold ion at the Booster injection leads to the prediction that the lost gold ion creates large number of positive ions, and even …
Date: June 22, 1998
Creator: Zhang, S. Y. & Ahrens, L. A.
System: The UNT Digital Library
Bounding CKM Mixing with a Fourth Family (open access)

Bounding CKM Mixing with a Fourth Family

CKM mixing between third family quarks and a possible fourth family is constrained by global fits to the precision electroweak data. The dominant constraint is from nondecoupling oblique corrections rather than the vertex correction to Z {yields} {bar b}b used in previous analyses. The possibility of large mixing suggested by some recent analyses of FCNC processes is excluded, but 3-4 mixing of the same order as the Cabbibo mixing of the first two families is allowed.
Date: April 22, 2009
Creator: Chanowitz, Michael S.
System: The UNT Digital Library
Brain Inflammation, Blood Brain Barrier dysfunction and Neuronal Synaptophysin Decrease after Inhalation Exposure to Titanium Dioxide Nano-aerosol in Aging Rats (open access)

Brain Inflammation, Blood Brain Barrier dysfunction and Neuronal Synaptophysin Decrease after Inhalation Exposure to Titanium Dioxide Nano-aerosol in Aging Rats

This article focuses on the consequences of TiO₂ distribution on the central nervous system and particularly on the blood-brain barrier functions.
Date: June 15, 2017
Creator: Disdier, Clémence; Chalansonnet, Monique; Gagnaire, François; Gaté, Laurent; Cosnier, Frédéric; Devoy, Jérôme et al.
System: The UNT Digital Library
Branching of Titanium Nanorods (open access)

Branching of Titanium Nanorods

This article reports that Ti nanorod branching occurs at a low homologous temperature of 0.28 based on physical vapor deposition and characterizations using electron microscopy and X-ray diffraction. The insight into conditions for branching, together with the determination of the morphology and crystal orientation of the branches, lay the foundation for further studies of branching mechanisms and driving force.
Date: April 22, 2021
Creator: Yussuf, Nosirudeen Abayomi & Huang, Hanchen
System: The UNT Digital Library
Breaking the Attosecond, Angstrom and TV/M Field Barriers with Ultra-Fast Electron Beams (open access)

Breaking the Attosecond, Angstrom and TV/M Field Barriers with Ultra-Fast Electron Beams

Recent initiatives at UCLA concerning ultra-short, GeV electron beam generation have been aimed at achieving sub-fs pulses capable of driving X-ray free-electron lasers (FELs) in single-spike mode. This use of very low Q beams may allow existing FEL injectors to produce few-100 attosecond pulses, with very high brightness. Towards this end, recent experiments at the LCLS have produced {approx}2 fs, 20 pC electron pulses. We discuss here extensions of this work, in which we seek to exploit the beam brightness in FELs, in tandem with new developments in cryogenic undulator technology, to create compact accelerator-undulator systems that can lase below 0.15 {angstrom}, or be used to permit 1.5 {angstrom} operation at 4.5 GeV. In addition, we are now developing experiments which use the present LCLS fs pulses to excite plasma wakefields exceeding 1 TV/m, permitting a table-top TeV accelerator for frontier high energy physics applications.
Date: June 22, 2012
Creator: Rosenzweig, James; Andonian, Gerard; Fukasawa, Atsushi; Hemsing, Erik; Marcus, Gabriel; Marinelli, Agostino et al.
System: The UNT Digital Library

Breaking the MDS-PIR Capacity Barrier via Joint Storage Coding

Paper explores the possibility of the capacity of private information retrieval (PIR) from databases coded using maximum distance separable (MDS) codes to be broken through joint encoding and storage of messages.
Date: August 22, 2019
Creator: Sun, Hua & Tian, Chao
System: The UNT Digital Library
Broadband THz response of a resonantly excited high-densityexciton gas (open access)

Broadband THz response of a resonantly excited high-densityexciton gas

The density-driven crossover of electron-hole pairs frominsulating to conducting states is observed via the internal 1s-2pexciton resonance. Decreasing interparticle distance induces strongshifts and broadening, and ultimately the disappearance of the excitonicresonance.
Date: November 22, 2004
Creator: Huber, Rupert; Kaindl, Robert A.; Schmid, Benjamin A. & Chemla,Daniel S.
System: The UNT Digital Library
Building Energy Information Systems: User Case Studies (open access)

Building Energy Information Systems: User Case Studies

Measured energy performance data are essential to national efforts to improve building efficiency, as evidenced in recent benchmarking mandates, and in a growing body of work that indicates the value of permanent monitoring and energy information feedback. This paper presents case studies of energy information systems (EIS) at four enterprises and university campuses, focusing on the attained energy savings, and successes and challenges in technology use and integration. EIS are broadly defined as performance monitoring software, data acquisition hardware, and communication systems to store, analyze and display building energy information. Case investigations showed that the most common energy savings and instances of waste concerned scheduling errors, measurement and verification, and inefficient operations. Data quality is critical to effective EIS use, and is most challenging at the subsystem or component level, and with non-electric energy sources. Sophisticated prediction algorithms may not be well understood but can be applied quite effectively, and sites with custom benchmark models or metrics are more likely to perform analyses external to the EIS. Finally, resources and staffing were identified as a universal challenge, indicating a need to identify additional models of EIS use that extend beyond exclusive in-house use, to analysis services.
Date: March 22, 2010
Creator: Granderson, Jessica; Piette, Mary Ann & Ghatikar, Girish
System: The UNT Digital Library
Bunch shape measurement of CW heavy-ion beam. (open access)

Bunch shape measurement of CW heavy-ion beam.

An accurate bunch shape measurement is one of the most important tasks during the fine tuning of multicavity accelerators. A device for the measurement of bunch time structure of cw heavy-ion beams with time resolution {approx}20 picoseconds was developed, constructed and commissioned at ATLAS which is a 50 MV superconducting heavy-ion linac. The Bunch Shape Monitor (BSM) is based on the analysis of secondary electrons produced by a primary beam hitting a tungsten wire to which a potential of -10 kV is applied. In a BSM the longitudinal distribution of charge of the primary beam is coherently transformed into a spatial distribution of low energy secondary electrons through transverse rf modulation. The distribution of secondary electrons is detected by a chevron MCP coupled to a phosphor screen. The signal image on the screen is measured by use of a CCD camera connected to a PC. This BSM analyzes cw beams rather than pulsed beams studied by a previous device [1]. Design features of the BSM and the beam measurement results are reported.
Date: August 22, 2002
Creator: Vinogradov, N. Y.; Billquist, P.; Ostroumov, P. N.; Pardo, R. C.; Portillo, M.; Sharamentov, S. I. et al.
System: The UNT Digital Library
c-axis twist Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} josephson junctions : a new phase-sensitive test of order parameter symmetry. (open access)

c-axis twist Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} josephson junctions : a new phase-sensitive test of order parameter symmetry.

Li et al. found that the critical current density J{sub c}{sup J} across atomically clean c-axis twist junctions of Bi{sub 2}Sr{sub 2}Ca Cu{sub 2}O{sub 8+{delta}} is the same as that of the constituent single crystal, J{sub c}{sup S}, independent of the twist angle {phi}{sub 0}, even at T{sub c}. They investigated theoretically if a d{sub x{sup 2}-y{sup 2}}-wave order parameter might twist by mixing in d{sub xy} components, but find that such twisting cannot possibly explain the data near to T{sub c}. Hence, the order parameter contains an s-wave component, but not any d{sub x{sup 2}-y{sup 2}}-wave component. In addition, the c-axis Josephson tunneling is completely incoherent. They also propose a c-axis junction tricrystal experiment which does not rely upon expensive substrates.
Date: January 22, 1999
Creator: Klemm, R. A.; Rieck, C. T. & Scharnberg, K.
System: The UNT Digital Library
C-H Functionalization Reactivity of a Nickel-Imide (open access)

C-H Functionalization Reactivity of a Nickel-Imide

This article discusses C-H functionalization reactivity of a Nickel-Imide.
Date: May 22, 2012
Creator: Wiese, Stefan; McAfee, Jason L.; Pahls, Dale R.; McMullin, Claire L.; Cundari, Thomas R., 1964- & Warren, Timothy H.
System: The UNT Digital Library
Cable Design for Fast Ramped Superconducting Magnets (Cos-θ Design). (open access)

Cable Design for Fast Ramped Superconducting Magnets (Cos-θ Design).

The new heavy ion synchrotron facility proposed by GSI will have two superconducting magnet rings in the same tunnel, with rigidities of 300 T-m and 100 T-m. Fast ramp times are needed, which can cause significant problems for the magnets, particularly in the areas of ac loss and magnetic field distortion. The development of the low loss Rutherford cable that can be used is described, together with a novel insulation scheme designed to promote efficient cooling. Measurements of contact resistance in the cable are presented and the results of these measurements are used to predict the ac losses, in the magnets during fast ramp operation. For the high energy ring, a lm model dipole magnet was built, based on the RHIC dipole design. This magnet was tested under boiling liquid helium in a vertical cryostat. The quench current showed very little dependence on ramp rate. The ac losses, measured by an electrical method, were fitted to straight line plots of loss/cycle versus ramp rate, thereby separating the eddy current and hysteresis components. These results were compared with calculated values, using parameters which had previously been measured on short samples of cable. Reasonably good agreement between theory and experiment was found, …
Date: March 22, 2004
Creator: Ghosh, A.
System: The UNT Digital Library
Calculation of Beam-Loaded Q in High-Power Klystrons (open access)

Calculation of Beam-Loaded Q in High-Power Klystrons

Instabilities in the gun region of a high-power klystron can occur when there is positive feedback between a mode and an induced current on the quasi-steady state beam emitted by the gun cathode[1]. This instability is dependent on the gun voltage, and is predicted on the basis of a negative total Q. The established method for computing the beam-loaded Q of a cavity involves using a time-dependent electromagnetic particle-in-cell (PIC) code to track beam particles through the quasi-static gun fields perturbed by the electromagnetic fields of a cavity eigenmode[2]. The energy imparted to the beam by the mode is obtained by integrating the Lorentz force along the particle tracks, and this quantity is simply related to the beam-loaded Q. We have developed an alternative approach that yields comparable accuracy but is computationally much simpler. The new method is based on a time-independent electrostatic PIC calculation, resulting in much faster solutions without loss of accuracy. We will present the theory and implementation of the new method, as well as benchmarks and results from analysis of the XP-4 klystron that show a potential instability near 3 GHz.
Date: February 22, 2006
Creator: DeFord, J. F.; Held, B.; Ivanov, V. & Ko, K.
System: The UNT Digital Library
CALIBRATION OF THE HB LINE ACTIVE WELL NEUTRON COINCIDENCE COUNTER FOR MEASUREMENT OF LANL 3013 HIGHLY ENRICHED URANIUM PRODUCT SPLITS (open access)

CALIBRATION OF THE HB LINE ACTIVE WELL NEUTRON COINCIDENCE COUNTER FOR MEASUREMENT OF LANL 3013 HIGHLY ENRICHED URANIUM PRODUCT SPLITS

In this paper we describe set-up, calibration, and testing of the F-Area Analytical Labs active well neutron coincidence counter(HV-221000-NDA-X-1-DK-AWCC-1)in SRNL for use in HB-Line to enable assay of 3013EU/Pu metal product. The instrument was required within a three-month window for availability upon receipt of LANL Category IV uranium oxide samples into the SRS HB-Line facility. We describe calibration of the instrument in the SRNL nuclear nondestructive assay facility in the range 10-400 g HEU for qualification and installation in HB-Line for assay of the initial suite of product samples.
Date: January 22, 2008
Creator: Dewberry, R; Donald02 Williams, D; Rstephen Lee, R; David-W Roberts, D & Leah Arrigo, L
System: The UNT Digital Library
Carbon Resistor Pressure Gauge Calibration at Low Stresses (open access)

Carbon Resistor Pressure Gauge Calibration at Low Stresses

The 470 Ohm carbon resistor gauge has been used in the stress range up to approximately 4-5 GPa for highly heterogeneous materials and/or divergent flow experiments. The attractiveness of the gauge is due to its rugged nature, simple construction, low cost, reproducibility, and survivability in dynamic events. The associated drawbacks are a long time response to pressure equilibration and gauge resistance hysteresis. In the range below 0.4 GPa, the gauge calibration has been mainly extrapolated into this regime. Because of the need for calibration data within this low stress regime, calibration experiments were performed using a split-Hopkinson bar, drop tower apparatus, and a gas pressure chamber. Since the performance of the gauge at elevated temperatures is a concern, the change in resistance due to heating at atmospheric pressure was also investigated. Details of the various calibration arrangements and the results will be discussed and compared a calibration curve fit to previously published calibration data.
Date: June 22, 2001
Creator: Cunningham, B; Vandersall, K S; Niles, A M; Greenwood, D W; Garcia, F & Forbes, J W
System: The UNT Digital Library
Carrots and Sticks: A Comprehensive Business Model for the Successful Achievement of Energy Efficiency Resource Standards Environmental Energy Technologies DivisionMarch 2011 (open access)

Carrots and Sticks: A Comprehensive Business Model for the Successful Achievement of Energy Efficiency Resource Standards Environmental Energy Technologies DivisionMarch 2011

Energy efficiency resource standards (EERS) are a prominent strategy to potentially achieve rapid and aggressive energy savings goals in the U.S. As of December 2010, twenty-six U.S. states had some form of an EERS with savings goals applicable to energy efficiency (EE) programs paid for by utility customers. The European Union has initiated a similar type of savings goal, the Energy End-use Efficiency and Energy Services Directive, where it is being implemented in some countries through direct partnership with regulated electric utilities. U.S. utilities face significant financial disincentives under traditional regulation which affects the interest of shareholders and managers in aggressively pursuing cost-effective energy efficiency. Regulators are considering some combination of mandated goals ('sticks') and alternative utility business model components ('carrots' such as performance incentives) to align the utility's business and financial interests with state and federal energy efficiency public policy goals. European countries that have directed their utilities to administer EE programs have generally relied on non-binding mandates and targets; in the U.S., most state regulators have increasingly viewed 'carrots' as a necessary condition for successful achievement of energy efficiency goals and targets. In this paper, we analyze the financial impacts of an EERS on a large electric utility …
Date: March 22, 2011
Creator: Satchwell, Andrew; Cappers, Peter & Goldman, Charles
System: The UNT Digital Library
Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization (open access)

Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization

Article examining the population mobility and air quality before and after the lockdown (mandated restriction of activity) during the public health response to COVID-19. This article is part of the Special Issue on COVID-19.
Date: January 22, 2022
Creator: Atkinson, Samuel F.; Kala, Abhishek K. & Tiwari, Chetan
System: The UNT Digital Library
The Case for Measuring and Reporting Bilingualism in Developmental Research (open access)

The Case for Measuring and Reporting Bilingualism in Developmental Research

Article argues that bilingualism and language experience in general should be routinely documented in all studies of infant and child development regardless of the research questions pursued, and provides suggestions for measuring and reporting children’s language exposure, proficiency, and use.
Date: August 22, 2019
Creator: Castro, Dina C.; Byers-Heinlein, Krista; Esposito, Alena G.; Winsler, Adam; Marian, Viorica & Luk, Gigi
System: The UNT Digital Library
cctbx news (open access)

cctbx news

The 'Computational Crystallography Toolbox' (cctbx, http://cctbx.sourceforge.net/) is the open-source component of the Phenix project (http://www.phenix-online.org/). Most recent cctbx developments are geared towards supporting new features of the phenix.refine application. Thus, the open-source mmtbx (macromolecular toolbox) module is currently being most rapidly developed. In this article we give an overview of some of the recent developments. However, the main theme of this article is the presentation of a light-weight example command-line application that was specifically developed for this newsletter: sequence alignment and superposition of two molecules read from files in PDB format. This involves parameter input based on the Phil module presented in Newsletter No. 5, fast reading of the PDB files with the new iotbx.pdb.input class, simple sequence alignment using the new mmtbx.alignment module, and use of the Kearsley (1989) superposition algorithm to find the least-squares solution for superposing C-alpha positions. The major steps are introduced individually, followed by a presentation of the complete application. The example application is deliberately limited in functionality to make it concise enough for this article. The main goal is to show how the open-source components are typically combined into an application. Even though the example is quite specific to macromolecular crystallography, we believe it …
Date: November 22, 2006
Creator: Grosse-Kunstleve, Ralf W.; Zwart, Peter H.; Afonine, Pavel V.; Ioerger, Thomas R. & Adams, Paul D.
System: The UNT Digital Library
CDFVME -- Software framework for testing VME boards (open access)

CDFVME -- Software framework for testing VME boards

New VME based boards are being produced for the Run II of the Collider Detector at Fermilab (CDF). These boards are being developed and tested at both Fermilab and offsite institutions. A software framework called CDFVME has been developed in which DAQ code can be easily written to control such boards in a test stand. The framework has been used to perform diagnostics at single board, multi-board, and multi-crate levels. This software framework runs on Unix, Linux and Windows NT platforms with a Java GUI communicating via LAN to multiple intelligent front end VME crates. All distributed processes are managed by a custom CORBA based software. The system has been ported to Motorola 68K and PPC front end processors running the VxWorks real-time kernel [1].
Date: July 22, 1999
Creator: Gay, C.
System: The UNT Digital Library
CENP-A mutations in Drosophila cause a BubR1-dependent earlymitotic delay without kinetochore localization of Spindle AssemblyCheckpoint components (open access)

CENP-A mutations in Drosophila cause a BubR1-dependent earlymitotic delay without kinetochore localization of Spindle AssemblyCheckpoint components

None
Date: May 22, 2006
Creator: Blower, Michael D.; Daigle, Tanya; Kaufman, Thom & Karpen, Gary H.
System: The UNT Digital Library
Centrality Dependent Strange Baryon Production in P-A and its Implications for Heavy Ion Collisions (open access)

Centrality Dependent Strange Baryon Production in P-A and its Implications for Heavy Ion Collisions

BNL E910 has measured strange baryon production as a function of collision centrality for 17.5 GeV/c p-Au collisions. Collision centrality is defined by v{sub 1} the mean number projectile-nucleon interactions estimated from the ''grey'' track multiplicity. The measured {Lambda} yield increases faster than the participant scaling expectation for v {le} 3 and then saturates. A simple parameterization of this dependence applied to nucleus-nucleus collisions reproduces the measured E866 km. and WA97 {Lambda} centrality dependent yields. The increase in {Lambda} production to v {le} 3 is also evident for {Lambda}s which are leading baryons, in disagreement with predictions from RQMD.
Date: September 22, 2000
Creator: Soltz, R.
System: The UNT Digital Library