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NLC photon collider option progress and plans (open access)

NLC photon collider option progress and plans

The idea of producing beams of high energy photons by Compton backscattering of laser photons was proposed over 20 years ago. At the time, producing the required laser pulses was not feasible. However, recent advances in high average power, diode pumped lasers appear to have solved this problem. The US Collaboration is now turning its attention to the engineering requirement of mating the laser and optics components with the accelerator structures in the confined space of the a colliding beam interaction region. The demonstration of a technically feasible interaction region design is planned for the Snowmass conference in 2001.
Date: August 31, 2000
Creator: Gronberg, J.
System: The UNT Digital Library
Natural-gas-assisted steam electrolysis for distributed hydrogen production (open access)

Natural-gas-assisted steam electrolysis for distributed hydrogen production

None
Date: August 29, 2000
Creator: Pham, A. Q.; Haslam, J. J.; Wallman, H.; DiCarlo, J. & Glass, R. S.
System: The UNT Digital Library
DARHT-II Downstream Beam Transport Beamline (open access)

DARHT-II Downstream Beam Transport Beamline

This paper describes the mechanical design of the downstream beam transport line for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT II) Facility. The DARHT-II project is a collaboration between LANL, LBNL and LLNL. DARHT II is a 20-MeV, 2000-Amperes, 2-{micro}sec linear induction accelerator designed to generate short bursts of x-rays for the purpose of radiographing dense objects. The downstream beam transport line is approximately 20-meter long region extending from the end of the accelerator to the bremsstrahlung target. Within this proposed transport line there are 15 conventional solenoid, quadrupole and dipole magnets; as well as several specialty magnets, which transport and focus the beam to the target and to the beam dumps. There are two high power beam dumps, which are designed to absorb 80-kJ per pulse during accelerator start-up and operation. Aspects of the mechanical design of these elements are presented.
Date: August 1, 2000
Creator: Westenskow, G A; Bertolini, L R; Duffy, P T & Paul, A C
System: The UNT Digital Library
Large-scale search for dark-matter axions (open access)

Large-scale search for dark-matter axions

We review the status of two ongoing large-scale searches for axions which may constitute the dark matter of our Milky Way halo. The experiments are based on the microwave cavity technique proposed by Sikivie, and marks a ''second-generation'' to the original experiments performed by the Rochester-Brookhaven-Fermilab collaboration, and the University of Florida group.
Date: August 30, 2000
Creator: Kinion, D. & van Bibber, K.
System: The UNT Digital Library
Transition From in-Plane to Out-of-Plane Azimuthal Enhancement in Au+Au Collisions (open access)

Transition From in-Plane to Out-of-Plane Azimuthal Enhancement in Au+Au Collisions

The incident energy at which the azimuthal distributions in semi-central heavy ion collisions change from in-plane to out-of-plane enhancement--E{sub tran} is studied as a function of mass of emitted particles, their transverse momentum and centrality for Au+Au collisions. The analysis is performed in a reference frame rotated with the sidewards flow angle ({Theta}{sub flow}) relative to the beam axis. A systematic decrease of E{sub tran} as function of mass of the reaction products, their transverse momentum and collision centrality is evidenced. The predictions of a microscopic transport model (IQMD) are compared with the experimental results.
Date: August 9, 2000
Creator: Andronic, A.; Stoicea, G.; Petrovici, M.; Simion, V.; Crochet, P.; Alard, J. P. et al.
System: The UNT Digital Library
Simplified Plant Analysis Risk (SPAR) Human Reliability Analysis (HRA) Methodology: Comparisons with other HRA Methods (open access)

Simplified Plant Analysis Risk (SPAR) Human Reliability Analysis (HRA) Methodology: Comparisons with other HRA Methods

The 1994 Accident Sequence Precursor (ASP) human reliability analysis (HRA) methodology was developed for the U.S. Nuclear Regulatory Commission (USNRC) in 1994 by the Idaho National Engineering and Environmental Laboratory (INEEL). It was decided to revise that methodology for use by the Simplified Plant Analysis Risk (SPAR) program. The 1994 ASP HRA methodology was compared, by a team of analysts, on a point-by-point basis to a variety of other HRA methods and sources. This paper briefly discusses how the comparisons were made and how the 1994 ASP HRA methodology was revised to incorporate desirable aspects of other methods. The revised methodology was renamed the SPAR HRA methodology.
Date: August 1, 2000
Creator: Byers, James Clifford; Gertman, David Ira; Hill, Susan Gardiner; Blackman, Harold Stabler; Gentillon, Cynthia Ann; Hallbert, Bruce Perry et al.
System: The UNT Digital Library
Ultradense Quark Stars From Perturbative QCD. (open access)

Ultradense Quark Stars From Perturbative QCD.

None
Date: August 27, 2000
Creator: Fraga, E. S.
System: The UNT Digital Library
Diesel Engine Electric Turbocompounding (open access)

Diesel Engine Electric Turbocompounding

Demo lower owning & operating costs by recovering exhaust energy Demo lower emissions by integrating w/diesel low NO{sub x} systems
Date: August 20, 2000
Creator: Callas, James
System: The UNT Digital Library
Review - HDD Regulations and Emission Control Systems (open access)

Review - HDD Regulations and Emission Control Systems

None
Date: August 20, 2000
Creator: Johnson, Timothy V.
System: The UNT Digital Library
Demonstrating Ultra-Low Diesel Vehicle Emissions (open access)

Demonstrating Ultra-Low Diesel Vehicle Emissions

Evaluate performance of near-term exhaust emissions control technologies on a modern diesel vehicle over transient drive cycles; Phase 1: Independent (separate) evaluations of engine-out, OEM catalysts, CDPF, and NOx adsorber (Completed March 2000); Phase 2: Combine NOx adsorber and CDPF to evaluate/demonstrate simultaneous reduction of NOx and PM (Underway--interim results available); Establish potential for these technologies to help CIDI engines meet emission reduction targets; and Investigate short-term effects of fuel sulfur on emissions performance
Date: August 20, 2000
Creator: McGill, R.N.
System: The UNT Digital Library
Research Approach for Aging and Evaluating Diesel Exhaust catalysts (open access)

Research Approach for Aging and Evaluating Diesel Exhaust catalysts

To determine the impact of diesel fuel sulfur levels on emissions control devices that could lower emissions of oxides of nitrogen (NOX) and particulate matter (PM) from on-highway trucks and buses in the 2002-2004 model years. West Virginia University is evaluating: - Diesel Oxidation Catalysts - Lean NOX Catalysts
Date: August 20, 2000
Creator: Wayne, Scott
System: The UNT Digital Library
Un-Regulated Emissions from CRT-Equipped Transit Buses (open access)

Un-Regulated Emissions from CRT-Equipped Transit Buses

Demonstrate applicability of the CRT TM to both new 4-stroke and older 2-stroke diesel engines Document the emissions reductions available using CRT TM retrofits in conjunction with reduced sulfur diesel fuel Evaluate the durability of CRTs in rigorous New York City bus service Apply new measurement and monitoring technologies for PM and toxic emissions Compare diesel-CRTTM with CNG and diesel-electric hybrid buses
Date: August 20, 2000
Creator: Gibbs, Richard
System: The UNT Digital Library
Combustion Commonality and Differences Between HSDI and Heavy Duty Truck Engines (open access)

Combustion Commonality and Differences Between HSDI and Heavy Duty Truck Engines

Experimental understanding of the diesel spray and combustion process at the fundamental level has helped advance the virtual lab simulation tools. The computational fluid dynamics (CFD)-based simulation has been globally verified in many engines, providing substantial credibility to the use of this technology in advanced engine development. This paper highlights the common aspects and differences between the smallbore HSDI and the larger displacement heavy-duty truck engine spray and combustion processes. Implications for combustion system strategies will be delineated. Detroit Diesel integrated ''Wired'' approach will be explained with pointers towards future tool enhancements.
Date: August 20, 2000
Creator: Chen, Rong
System: The UNT Digital Library
Association of ventilation with health and other responses in commercial and institutional buildings (open access)

Association of ventilation with health and other responses in commercial and institutional buildings

The paper presents a summary of a review [1] of current literature on the associations of ventilation rates in non-residential and non-industrial buildings (primarily offices) with health and other human outcomes. Twenty studies, with close to 30,000 subjects, investigated the association of ventilation rates with human responses. (Twenty one studies investigating the association of carbon dioxide with human responses, although included in the previous review, are not summarized here.) Almost all studies including ventilation rates below 10 Ls{sup -1} per person found these ventilation rates to be associated in all building types with statistically significant worsening in one or more health or perceived air quality outcomes. Some studies comparing only ventilation rates above 10 Ls{sup -1} per person determined that increases in ventilation rate above 10 Ls{sup -1} per person, up to approximately 20 Ls{sup -1} per person, were associated with further significant decreases in the prevalence of SBS symptoms or with further significant improvements in perceived air quality. The studies reported relative risks of 1.5-2 for respiratory illnesses and 1.1-6 for sick building syndrome symptoms for low compared to high ventilation rates.
Date: August 1, 2000
Creator: Seppanen, Olli; Fisk, William J. & Mendell, Mark J.
System: The UNT Digital Library
DEVELOPMENT OF UREA-SCR FOR HEAVY-DUTY TRUCKS DEMONSTRATION UPDATE (open access)

DEVELOPMENT OF UREA-SCR FOR HEAVY-DUTY TRUCKS DEMONSTRATION UPDATE

This study included engine cell and vehicle tests. The engine cell tests are aimed at determining NOX reduction using the US transient and OICA emissions test cycles. These cycles will be included in future US HD emissions standards. The vehicle tests will show urea-SCR system performance during real-world operation. These tests will prove that the technology can be successfully implemented and demonstrated over-the-road. The program objectives are to: (a) apply urea-SCR to a US HD diesel engine; (b) determine engine cell emissions reduction during US-transient and OICA cycles; (c) apply urea-SCR to a US HD diesel truck; and (d) determine NOX reduction and urea consumption during over-the-road operation.
Date: August 20, 2000
Creator: Miller, William
System: The UNT Digital Library
Multiple Air Toxics Exposure Study Exposure Study (MATES II)in the South Coast Air Basin (open access)

Multiple Air Toxics Exposure Study Exposure Study (MATES II)in the South Coast Air Basin

Ambient Toxics Monitoring Toxics Emissions Inventory Modeling/Risk Assessment.
Date: August 20, 2000
Creator: Zeldin, Mel
System: The UNT Digital Library
HCCI Combustion Fundamentals: In-Cylinder Diagnostics and Kinetic-Rate Computations (open access)

HCCI Combustion Fundamentals: In-Cylinder Diagnostics and Kinetic-Rate Computations

Substantial progress has been made in reducing emissions and improving the performance of Diesel engines. Appears to be a lower limit for engine-out NOX of about 1 g/hp-hr. Serious difficulty in meeting Tier II or newly proposed H-D standards. Homogeneous charge compression ignition (HCCI) is an alternative IC engine combustion process that has the potential to: Provide diesel-like or higher efficiencies. Very low engine-out NOX due to low combustion temperatures. Very low particulate (PM) emissions. HCCI engine combustion is not well understood, and research is required to resolve technical barriers, including:
Date: August 20, 2000
Creator: Dec, John E.
System: The UNT Digital Library
Diesel Fuel Sulfur Effects on the Performance of Lean NOx Catalysts (open access)

Diesel Fuel Sulfur Effects on the Performance of Lean NOx Catalysts

Evaluate the effects of diesel fuel sulfur on the performance of low temperature and high temperature Lean-NOx Catalysts. Evaluate the effects of up to 250 hours of aging on the performance of the Lean-NOx Catalysts with different fuel sulfur contents.
Date: August 20, 2000
Creator: Ren, Shouxian
System: The UNT Digital Library
IMPACT OF OXYGENATED FUEL ON DIESEL ENGINE PERFORMANCE AND EMISSIONS (open access)

IMPACT OF OXYGENATED FUEL ON DIESEL ENGINE PERFORMANCE AND EMISSIONS

As evidenced by recent lawsuits brought against operators of large diesel truck fleets [1] and by the Consent Decree brought against the heavy-duty diesel manufacturers [2], the environmental and health effects of diesel engine emissions continue to be a significant concern. Reduction of diesel engine emissions has traditionally been achieved through a combination of fuel system, combustion chamber, and engine control modifications [3]. Catalytic aftertreatment has become common on modern diesel vehicles, with the predominant device being the diesel oxidation catalytic converter [3]. To enable advanced after-treatment devices and to directly reduce emissions, significant recent interest has focused on reformulation of diesel fuel, particularly the reduction of sulfur content. The EPA has man-dated that diesel fuel will have only 15 ppm sulfur content by 2007, with current diesel specifications requiring around 300 ppm [4]. Reduction of sulfur will permit sulfur-sensitive aftertreatment devices, continuously regenerating particulate traps, NOx control catalysts, and plasma assisted catalysts to be implemented on diesel vehicles [4]. Another method of reformulating diesel fuel to reduce emissions is to incorporate oxygen in the fuel, as was done in the reformulation of gasoline. The use of methyl tertiary butyl ether (MTBE) in reformulated gasoline has resulted in contamination of …
Date: August 20, 2000
Creator: Boehman, Andre L.
System: The UNT Digital Library
Diesel Emissions Control- Sulfur Effects (DECSE): Summary of PM Results and Data (open access)

Diesel Emissions Control- Sulfur Effects (DECSE): Summary of PM Results and Data

Determine the impact of fuel sulfur levels on emission control systems that could be implemented to lower emissions of NOx and PM from on-highway trucks in the 2002-2004 time frame.
Date: August 20, 2000
Creator: Gorse, Jr. Robert A.
System: The UNT Digital Library
ARB's Heavy-Duty Vehicle Smoke Inspection Program (open access)

ARB's Heavy-Duty Vehicle Smoke Inspection Program

None
Date: August 20, 2000
Creator: Jacobs, Paul E.
System: The UNT Digital Library
The Influence of Light Weight Materials on Fuel Economy and Emissions in Heavy Duty Diesel Engine (open access)

The Influence of Light Weight Materials on Fuel Economy and Emissions in Heavy Duty Diesel Engine

Technologies being developed that will allow for the substitution of aluminum for cast iron in engine heads and blocks, while maintaining performance and durability. Development of lightweight diesel engine technology: funded by NAVY, DOE and TACOM
Date: August 20, 2000
Creator: Becker, Paul C.
System: The UNT Digital Library
COMPARISON OF PLASMA-CATALYST AND ACTIVE LEAN NOx CATALYST (open access)

COMPARISON OF PLASMA-CATALYST AND ACTIVE LEAN NOx CATALYST

A number of NO{sub x} control systems are being discussed for potential application to diesel engines. Unfortunately, it can be difficult to compare systems on an equal basis because data are run under different conditions, or reported against different test cycles, or not shown over a range of operating conditions. In addition, the fuel consumption penalty associated with the NO{sub x} control technologies is not always reported. In this paper, we compare two diesel NO{sub x} aftertreatment systems: (1) Plasma-Catalyst (PC): a nonthermal plasma followed by a catalyst; and (2) Active Lean NO{sub x} Catalyst (ALNC): a NO{sub x} catalyst designed to selectively reduce NO{sub x} using hydrocarbon (HC) in the form of diesel fuel. Fuel is added to the exhaust to increase HC above normal diesel levels. These systems will be described in more detail in this report.
Date: August 20, 2000
Creator: Hoard, John
System: The UNT Digital Library
OVERVIEW OF ADVANCED PETROLEUM-BASED FUELS-DIESEL EMISSIONS CONTROL PROGRAM (APBF-DEC) (open access)

OVERVIEW OF ADVANCED PETROLEUM-BASED FUELS-DIESEL EMISSIONS CONTROL PROGRAM (APBF-DEC)

The Advanced Petroleum-Based Fuels-Diesel Emissions Control Program (APBF-DEC) began in February 2000 and is supported by government agencies and industry. The purpose of the APBF-DEC program is to identify and evaluate the optimal combinations of fuels, lubricants, diesel engines, and emission control systems to meet the projected emission standards for the 2000 to 2010 time period. APBF-DEC is an outgrowth of the earlier Diesel Emission Control-Sulfur Effects Program (DECSE), whose objective is to determine the impact of the sulfur levels in fuel on emission control systems that could lower the emissions of NOx and particulate matter (PM) from diesel powered vehicles in the 2002 to 2004 period. Results from the DECSE studies of two emission control technologies-diesel particle filter (DPF) and NOx adsorber-will be used in the APBF-DEC program. These data are expected to provide initial information on emission control technology options and the effects of fuel properties (including additives) on the performance of emission control systems.
Date: August 20, 2000
Creator: Sverdrup, George M.
System: The UNT Digital Library