Motor exhaust

A steady-state rocket-type combustion spray unit has been developed, called high velocity oxy fuel (HVOF), that creates a steady state, continuous, supersonic spray stream (1.2—3 mm dia) resembling a rocket motor exhaust. The portable device injects and accelerates the particles inside a barrel (rocket nozzle). It produces coating quaHty and particle velocities equal to the D-gun at 5—10 times the spray rate with significantly reduced coating costs. 

Please notice that in a well-ventilated laboratory and a pressure cell, these experiments can be executed safely. In seven years of graduate research activity at the Chemical Engineering Department of the University of Akron, only one catalyst ignition and one real CO alarm occurred. Several false CO alarms were sounded until someone noticed that they always happened about 2 30 PM. As it turned out, one maintenance employee parked his old car right in front of the air intake to the lab ventilation. He warmed up his car for a while before he started to go home after his shift, and the motor exhaust gas set off the false alarms. 

TABLE 13.21 Optionai Factory Calibration for Motor Exhaust Gas Typical Measuring Ranges ... 

Motor exhaust gas. Helsinki Temer instruments, http //ternet.fi/exhaust.htm. 

Chamberlain A, Heard C, Little MJ, et al. 1978. Investigations into lead from motor vehicles. Harwell, United Kingdom United Kingdom Atomic Energy Authority. Report no. AERE-9198. 1979. The dispersion of lead from motor exhausts. Philos Trans R Soc Lond A 290 557-589. 

Little, P. and R. D. Wiffen. Emission and deposition of lead from motor exhausts. II. Airborne concentration, particle size and deposition of lead near motorways. Atmos. Environ. 12 1331-1341 (1978). 

Kawamura, K., and I. R. Kaplan, Motor Exhaust Emissions as a Primary Source for Dicarboxylic Acids in Los Angeles Ambient Air, Environ. Sci. Technol., 21, 105-110 (1987). 

Holmberg, B., and U. Ahlborg, Eds., Symposium on Biological Tests in the Evaluation of Mutagenicity and Carcinogenicity of Air Pollutants with Special Reference to Motor Exhausts and Coal Combustion Products, Stockholm, Sweden, February 8-12, in Environ. Health Perspect., 47, 1-345 (1983). 

Hanning-Lee, M. A., B. B. Brady, L. R. Martin, and J. A. Syage, Ozone Decomposition on Alumina Implications for Solid Rocket Motor Exhaust, Geophys. Res. Lett, 23, 1961-1964 (1996). 

Ross, M Local Effects of Solid Rocket Motor Exhaust on Stratospheric Ozone, J. Spacecraft Rockets, 33, 144-353 (1996). 

Catalytic converters use palladium and related metals to rid motor exhaust of its noxious gases... 

The most important attributes of this invention are high impulse performance coupled with high exit temperature on primary combustion and favorable boron species in the primary motor exhaust. The system is also insensitive to impact and possesses excellent thermal stability at elevated temperatures. Additionally, the system is readily castable since the addition of solid oxidizers is not required. Further, high flexibility in the ballistic properties of the gas generator can be achieved by the addition of solid oxidizers such as ammonium nitrate, ammonium perchlorate, hydroxylammonium perchlorate, potassium perchlorate, lithium perchlorate, calcium nitrate, barium perchlorate, RDX, HMX etc. The oxidizers are preferably powdered to a particle size of about 10 to 350 microns [13]. 

Burnout Time is the time in which a rocket motor exhausts its fuel supply. It is usually measured from the time of ignition Ref Glossary of Ord(1959), 51... 

Afterburning Predictions for Metal-Modified Propellant Motor Exhausts , AIAA J 14 (7),... 

Abstract Gaseous and particulate emissions from vehicles represent a major source of atmospheric pollution in cities. Recent research shows evidence of, along with the primary emissions from motor exhaust, important contributions from secondary (due to traffic-related organic/inorganic gaseous precursors) and primary particles due to wear and resuspension processes. Besides new and more effective (for NO emissions) technologies, non-technological measures from local authorities are needed to improve urban air quality in Europe. 

It has been suggested that the planting of trees alongside motorways might reduce the dispersion over from motor exhausts. Little Wiffen showed that the measured vg values, when related to the foliar surface of a belt of trees, would not be enough to reduce the amount of lead dispersed significantly. 

An advantage of the use of radioactive tracers is that uptake and elimination of a potentially toxic substance can be studied without any perceptible increase in its concentration in the body. Also, the criticism was made that the aerosols used by Kehoe and by Griffin et al. were not identical with those produced in motor exhaust. To study uptake following inhalation of exhaust lead, a method of incorporating a tracer was developed at Harwell. 

Wells, A.C., Venn, J.B. Heard, M.J. (1977) Deposition of the lung and uptake to blood of motor exhaust labelled with 203Pb. In Inhaled Particles, IV, ed. W.H. Walton, pp. 175-88. Oxford Pergamon. 

The first five chapters of this book are about radioactive nuclides of potential concern to public health. In the sixth chapter, some applications to the study of boundary layer transport are discussed. In the last chapter examples are given of using radioactive aerosols to study deposition of particles in the lung and the subsequent uptake into the body. The widespread dissemination of lead aerosol from motor exhausts, its inhalation by the public, and fallout onto crops, present problems of analysis not dissimilar to those of radioactive emissions. Experiments in which volunteers inhaled motor exhaust labelled with 2°3pb provided one piece of evidence to fit into the picture. 

Filtration and chemical reactions can be usefully integrated in order to separate diesel soot particles efficiently from motor exhaust gases, and this is illustrated by Rieckmann and Volker in Chapter 15, together with a series of other examples of reactive filtration processes which are realized in the chemical industries. 

Wohlslagel, J., L.C.DiPasquale, and E.H.Vernot. 1976. Toxicity of solid rocket motor exhaust effects of HC1, HF, and alumina on rodents. J. Combust. Toxicol. 3 61-70. 

Aeetie acid is produced photoehemieally mainly from reactions of the peroxy acetyl radical (CH3CO3) wifli oflier peroxy radieals. For example, the reaction of CH3CO3 with HO2 is known to lead to about 20% CH3C(0)OH (Tyndall et al, 2001). Aeetie acid in the gas phase is also produced by reaction of ozone with various olefins like propene, butene or pentene (Atkinson and Arey, 2003). A total photochemical source strength of 120 Tg/year has been reported (Baboukas et al, 2000). The contribution of direct emissions from anthropogenie (biomass eombustion, motor exhaust) and biogenie (bacteria metabolisms, emission from soil and vegetation) sourees is estimated at 48 Tg/year (Chebbi and Carlier, 1996). 

EXPOSURE ROUTES Inhalation (motor exhaust, highly industrialized cities and ambient air near oil refineries or chemical factories) ingestion (drinking water and plastic and rubbei food containers) occupational exposure. 

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