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Chemical and physical properties of various plastics used for plastic abrasive applications are presented. All testing is done in compliance with MIL-P-85891 (AS), “Plastic Media for Removal of Organic Coatings”. Density and heavy density particle contamination are particularly important tests relative to aerospace applications.

Performance of various plastic abrasive materials is compared in a typical aerospace coatings removal application. Media aggressiveness towards substrates, stripping capabilities, effects of plastic breakdown, and plastic consumption are compared. Lower density plastics are shown to be more substrate protective than higher denisty plastics. Stripping rates are shown to be dependent both on plastic hardness and breakdown resistance of the plastic.

Optimization parameters designed to minimize residual stress and maximize coatings removal rates are presented. Stress saturation curves are presented and compared for the optimized blasting parameters using different plastic abrasive materials.

This paper summarizes the Next Generation Natural Gas Vehicle (NG-NGV) Program that is led by the U.S. Department Of Energy's (DOE's) Office of Heavy Vehicle Technologies (OHVT) through the National Renewable Energy Laboratory (NREL). The goal of this program is to develop and implement one Class 3-6 compressed natural gas (CNG) prototype vehicle and one Class 7-8 liquefied natural gas (LNG) prototype vehicle in the 2004 to 2007 timeframe. OHVT intends for these vehicles to have 0.5 g/bhp-hr or lower emissions of oxides of nitrogen (NOx) by 2004 and 0.2 g/bhp-hr or lower NOx by 2007. These vehicles will also have particulate matter (PM) emissions of 0.01 g/bhp-hr or lower by 2004. In addition to ambitious emissions goals, these vehicles will target life-cycle economics that are compatible with their conventionally fueled counterparts.

A program has been completed to evaluate ultra-low sulfur diesel fuels and passive diesel particulate filters (DPFs) in truck and bus fleets operating in southern California. The fuels, ECD and ECD-1, are produced by ARCO (a BP Company) and have less than 15 ppm sulfur content. Vehicles were retrofitted with two types of catalyzed DPFs, and operated on ultra-low sulfur diesel fuel for over one year. Exhaust emissions, fuel economy and operating cost data were collected for the test vehicles, and compared with baseline control vehicles. Regulated emissions are presented from two rounds of tests. The first round emissions tests were conducted shortly after the vehicles were retrofitted with the DPFs. The second round emissions tests were conducted following approximately one year of operation. Several of the vehicles retrofitted with DPFs accumulated well over 100,000 miles of operation between test rounds.

The Advanced Petroleum-Based Fuels - Diesel Emissions Control (APBF-DEC) project is a joint U.S. government/industry research effort to identify optimal combinations of fuels, lubricants, engines, and emission control systems to meet projected emissions regulations during the period 2000 to 2010. APBF-DEC is conducting five separate projects involving light- and heavy-duty engine platforms. Four projects are focusing on the performance of emission control technologies for reducing criteria emissions using different fuels. This project is investigating the effects of lubricant formulation on engine-out emissions (Phase I) and the resulting impact on emission control systems (Phase II). This paper describes the statistical design and analysis methods used during Phase I of the lubricants project.

Tests were conducted during 2008 on 16 late-model, conventional vehicles (1999 through 2007) to determine short-term effects of mid-level ethanol blends on performance and emissions. Vehicle odometer readings ranged from 10,000 to 100,000 miles, and all vehicles conformed to federal emissions requirements for their federal certification level. The LA92 drive cycle, also known as the Unified Cycle, was used for testing as it was considered to more accurately represent real-world acceleration rates and speeds than the Federal Test Procedure (FTP) used for emissions certification testing. Test fuels were splash-blends of up to 20 volume percent ethanol with federal certification gasoline. Both regulated and unregulated air-toxic emissions were measured. For the aggregate 16-vehicle fleet, increasing ethanol content resulted in reductions in average composite emissions of both NMHC and CO and increases in average emissions of ethanol and aldehydes.

Increasing fuel costs and the desire for reduced dependence on foreign oil have brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. One of the obstacles to the increased use of diesel engines in this platform is the Tier 2 emission standards. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies-such as common rail fuel injection systems, low-sulfur diesel fuel, oxides of nitrogen (NOX) adsorber catalysts or NACs, and diesel particle filters (DPFs)-allows for the development of powertrain systems that have the potential to comply with these future requirements. In support of this, the U.S. Department of Energy (DOE) has engaged in several test projects under the Advanced Petroleum Based Fuels-Diesel Emission Control (APBF-DEC) activity [1, 2, 3, 4, 5].

Due to its high efficiency and superior durability, the diesel engine is again becoming a prime candidate for future light-duty vehicle applications within the United States. While in Europe the overall diesel share exceeds 40%, the current diesel share in the United States is 1%. Despite the current situation and the very stringent Tier 2 emission standards, efforts are being made to introduce the diesel engine back into the U.S. market. In order to succeed, these vehicles have to comply with emissions standards over a 120,000 miles distance while maintaining their excellent fuel economy. The availability of technologies-such as high-pressure, common-rail fuel systems; low-sulfur diesel fuel; oxides of nitrogen (NOx) adsorber catalysts or NACs; and diesel particle filters (DPFs)-allow the development of powertrain systems that have the potential to comply with the light-duty Tier 2 emission requirements. In support of this, the U.S.

Both field research and certification data show that the lean burn natural gas powered spark ignition engines offer particulate matter (PM) reduction with respect to equivalent diesel power plants. Concerns over PM inventory make these engines attractive despite the loss of fuel economy associated with throttled operation. Early versions of the Cummins L-10 natural gas engines employed a mixer to establish air/fuel ratio. Emissions measurements by the West Virginia University Transportable Heavy Duty Emissions Testing Laboratories on Cummins L-10 powered transit buses revealed the potential to offer low emissions of PM and oxides of nitrogen, (NOx) but variations in the mixture could cause emissions of NOx, carbon monoxide and hydrocarbons to rise. This was readily corrected through mixer repair or readjustment. Newer versions of the L-10 engine employ a more sophisticated fueling scheme with feedback control from a wide range oxygen sensor.

In this study, a 15-L heavy-duty diesel engine and an emission control system consisting of diesel oxidation catalysts, NOx adsorber catalysts, and diesel particle filters were evaluated over the course of a 2000 hour aging study. The work is a follow-on to a previously documented development effort to establish system regeneration and sulfur management strategies. The study is one of five projects being conducted as part of the U.S. Department of Energy's Advanced Petroleum Based Fuels - Diesel Emission Control (APBF-DEC) activity. The primary objective of the study was to determine if the significant NOx and PM reduction efficiency (>90%) demonstrated in the development work could be maintained over time with a 15-ppm sulfur diesel fuel. The study showed that high NOx reduction efficiency can be restored after 2000 hours of operation and 23 desulfation cycles.

The procedure utilized during a research evaluation of the effect of agglomerates in heavy fuels is described, and a simple light microscopic method for the study of particle dispersion in heavy fuels is given. The effectiveness of commercial additives for the treatment of heavy fuels to initiate dispersion is outlined as well as the development of a fast and inexpensive filtration test for accurately measuring the effect of various additives on various heavy fuels. Finally, the basic development work and the results obtained using ultrasonic dispersion of agglomerates during an actual engine performance test with heavy residual fuel oil is presented.

Application of electron microscopy to the study of fractures and fracture mechanisms is reviewed. Static fractures and the fracture of multiphased alloys have been studied, and significant information obtained. Striations on the fracture surface are associated with fatigue crack propagation and are directly related to crack growth rates. Various factors such as strength level, corrosive media, and second-phase particles are known to influence the appearance of the striations under the electron microscope. Since the appearance under the microscope of each type of fracture is quite unique, electron microscopic fractography is also an aid in service failure analyses.

Experimental results obtained with a continuous culture system for the cultivation of Hydrogenomonas eutropha for waste management in a life-support system indicate that a reliable and stable system can be designed under the present state-of-the-art. The present system provides for control of hydrogen, oxygen, carbon dioxide, pH, cell density, temperature, urea, and ammonia during growth. The culture system design is adaptable to operation in a zero-gravity field, and should be adaptable to integration with proposed water electrolysis and product recovery systems for waste management in an overall life support system.

Experimental research on an integrated Bosch reactor and water-vapor electrolysis unit for oxygen recovery from carbon dioxide is described. A principal feature of the integration is the use of regenerable solid absorbent for periodic water-vapor transfer in a gravity-independent manner to avoid gas-liquid separation problems. The carbon dioxide reduction subsystem was based on batch-wise operation of two Bosch reactors to permit periodic shutdown for carbon removal. Experimental results are presented on operation of the Bosch reactor which include catalyst activation, recycle rate, recycle gas composition, reactor temperature, catalyst consumption, packing density of carbon and life of reactor materials during extended operation. Experimental data are presented on the solid-absorbent unit with silica gel and synthetic zeolites for removal of water vapor from the Bosch reaction and for water-vapor feed to an electrolysis unit.

The Cold Cranking Simulator (CCS) has been shown to be a relatively inexpensive, fast, and accurate instrument for measurement of motor oil viscosity at low temperatures. ASTM cooperative work with the CCS has resulted in establishment of a Tentative Method, D 2602-67T, for motor oil viscosity at 0 F. Further data show that the method could be extended to -20 F if desired. The SAE has adopted the new Cold Cranking Simulator Method as the basis for revision of the J300 motor oil winter grade viscosity classification. This paper summarizes the efforts leading to the solution of a problem of ten years' standing.

After several alternative procedures were investigated for preparing chromium-plated zinc die castings for painting, one procedure proved best for contaminated chromium surfaces. This procedure included six steps: (1) alkaline spray cleaning, (2) electrolytic alkaline cleaning, (3) rinsing with high-purity water with a specific resistance of 500,000-700,000 ohm-cm, (4) immersing in chromic acid solution (0.05 oz/gal) at 150 F for 2 minutes, or treating cathodically in 0.7 oz/gal of sodium dichromate with a current density of 0.05 amp/sq ft for 30-60 sec, (5) rinsing with high-purity water, (6) forced-air drying with filtered air at 15 psi. Good adherence was obtained by following these procedures and painting with a single coat of acrylic or alkyd-resin paint. Other preparation procedures resulted in inferior paint adherence.

In recent years alternative automobile power technologies have received increased attention from OEM's, special interest groups, and the public. Plausible power technologies now include internal combustion engines, batteries, fuel cells, and a variety of hybrid technologies. The merits of each of these technologies as a means to move personal and fleet transportation into the next century have been highly debated. One technology that has emerged as a viable alternative to the internal combustion engine is the fuel cell. Considering arguments on all sides of the debate, the authors describe the results of a systematic, focused examination of the sustainability of fuel cells for transportation and discuss strategies for sustainable technology design. Sustainable technologies are those that contribute to preserving or improving societal quality, the environment, and the economy for future generations.

A commercially available axial piston water hydraulic pump (Danfoss PAH 10) was evaluated under a range of pressures, speeds and fluid temperatures. Three candidate fluids were used in this evaluation: filtered tap water (as a baseline), a mixture of tap water and polypropylene glycol based antifreeze, and finally a mixture of synthetic seawater and polypropylene glycol based antifreeze. The effect of the fluids and temperatures on the pump efficiency was observed. The evaluation provides the basis for the design of a non-polluting variable flow water-antifreeze hydraulic power source.