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1

Exhaust gas recirculation control  

Microsoft Academic Search

A transducer regulates an operating pressure which positions an exhaust gas recirculation control valve pintle to provide exhaust gas recirculation at rates which maintain the pressure in the recirculation passage upstream of the valve pintle equal to a reference pressure; exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is substantially proportional to induction air flow. The transducer

Haka

1979-01-01

2

Exhaust gas recirculation control  

Microsoft Academic Search

A transducer creates an operating pressure that positions a control valve to provide exhaust gas recirculation at rates which maintain the control pressure in the recirculation passage between the valve and an orifice equal to a reference pressure; exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is substantially proportional to induction air flow. The transducer also varies

Vogelsberg

1979-01-01

3

Exhaust gas recirculation control  

Microsoft Academic Search

In an internal combustion engine, recirculation of exhaust gases is controlled to maintain the control pressure in a zone of the recirculation passage proportional to a reference pressure and thus to provide exhaust gas recirculation as a proportion of induction air flow. A duty cycle modulated valve controls an exhaust backpressure port and an atmospheric pressure port to create the

Stoltman

1983-01-01

4

Exhaust gas recirculation control  

SciTech Connect

In an internal combustion engine, recirculation of exhaust gases is controlled to maintain the control pressure in a zone of the recirculation passage proportional to a reference pressure and thus to provide exhaust gas recirculation as a proportion of induction air flow. A duty cycle modulated valve controls an exhaust backpressure port and an atmospheric pressure port to create the reference pressure, whereby the proportion of exhaust gases recirculated is established by the duty cycle and is independent of the induction air flow.

Stoltman, D.D.

1983-08-23

5

Exhaust gas recirculation control  

SciTech Connect

A regulating unit senses the pressures in two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to a reference pressure. Exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is a proportion of induction air flow with the proportion being ruled by the regulating unit.

Stoltman, D.D.

1980-04-08

6

Exhaust gas recirculation control  

Microsoft Academic Search

A regulating unit senses the pressures in two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to a reference pressure. Exhaust gas recirculation thus varies

Stoltman

1980-01-01

7

Exhaust gas recirculation control  

SciTech Connect

A switching member simultaneously establishes a reference pressure and selects the pressure in one of two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to the reference pressure. Exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is a proportion of induction air flow with the proportion being ruled by the switching member.

Haka, R. J.; Stoltman, D. D.

1980-02-05

8

Exhaust gas recirculation system  

SciTech Connect

An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in a control vacuum opposing the air pressure force and modified by an air bleed device as a function of changes in engine exhaust gas backpressure levels, to provide an EGR valve movement that varies essentially in proportion to changes in engine air flow.

Rachedi, S.H.

1983-08-30

9

Exhaust gas recirculation system  

Microsoft Academic Search

An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in

Rachedi

1983-01-01

10

Exhaust gas recirculation control  

Microsoft Academic Search

A switching member simultaneously establishes a reference pressure and selects the pressure in one of two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to

R. J. Haka; D. D. Stoltman

1980-01-01

11

Multistage exhaust gas recirculation system  

Microsoft Academic Search

An automotive type exhaust gas recirculation (EGR) system has two modes of operation, a first one that regulates EGR flow at a constant percentage rate as a function of throttle valve position independently of exhaust gas backpressure changes, and a second one that provides a variable percentage rate of flow of EGR gases in response to changes in exhaust gas

D. C. Ahrns; S. H. Rachedi

1983-01-01

12

High speed exhaust gas recirculation valve  

DOEpatents

In order to minimize pollutants such as Nox, internal combustion engines typically include an exhaust gas recirculation (EGR) valve that can be used to redirect a portion of exhaust gases to an intake conduit, such as an intake manifold, so that the redirected exhaust gases will be recycled. It is desirable to have an EGR valve with fast-acting capabilities, and it is also desirable to have the EGR valve take up as little space as possible. An exhaust gas recirculation valve is provided that includes an exhaust passage tube, a valve element pivotally mounted within the exhaust passage tube, a linear actuator; and a gear train. The gear train includes a rack gear operatively connected to the linear actuator, and at least one rotatable gear meshing with the rack gear and operatively connected to the valve element to cause rotation of the valve element upon actuation of the linear actuator. The apparatus provides a highly compact package having a high-speed valve actuation capability.

Fensom, Rod (Peterborough, GB); Kidder, David J. (Peterborough, GB)

2005-01-18

13

Exhaust gas sensors  

SciTech Connect

The automotive industry needed a fast, reliable, under-the-hood method of determining nitrogen oxides in automobile exhaust. Several technologies were pursued concurrently. These sensing technologies were based on light absorption, electrochemical methods, and surface mass loading. The Y-12 plant was selected to study the methods based on light absorption. The first phase was defining the detailed technical objectives of the sensors--this was the role of the automobile companies. The second phase was to develop prototype sensors in the laboratories--the national laboratories. The final phase was testing of the prototype sensors by the automobile industries. This program was canceled a few months into what was to be a three-year effort.

Hiller, J. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Miree, T.J. [Ford Motor Co., Allen Park, MI (United States)

1997-02-09

14

Investigation of organic pollutants from house heating systems using biogenic fuels and correlations with other exhaust gas components  

Microsoft Academic Search

Biogenic fuels are an interesting alternative to reduce the CO2 emission from energy plants and general heat supply. In contrast to wood as a fuel, biogenic fuels are much more critical because of their higher content of chloride, which seems to be an essential factor for the formation of chlorinated organic compounds. In the exhaust gases from hay and straw

O Vierle; T Launhardt; A Strehler; R Dumler-Gradl; H Thoma; M Schreiner

1999-01-01

15

Exhaust gas clean up process  

DOEpatents

A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ is described. The method involves prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ gas or nitrogen sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt. 4 figs.

Walker, R.J.

1988-06-16

16

Exhaust gas clean up process  

DOEpatents

A method of cleaning an exhaust gas containing particulates, SO.sub.2 and NO.sub.x includes prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO.sub.x and SO.sub.2, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO.sub.x is removed as N.sub.2 or nitrogen-sulfonate ions and the oxides of sulfur are removed as a vaulable sulfate salt.

Walker, Richard J. (McMurray, PA)

1989-01-01

17

Multi-stage exhaust gas recirculation system  

SciTech Connect

An automotive type exhaust gas recirculation (EGR) system has two modes of operation, a first one that regulates EGR flow at a constant percentage rate as a function of throttle valve position independently of exhaust gas backpressure changes, and a second one that provides a variable percentage rate of flow of EGR gases in response to changes in exhaust gas backpressures, both modes utilizing carburetor ported vacuum modified by an air bleed device as the EGR valve opening force.

Ahrns, D.C.; Rachedi, S.H.

1983-08-16

18

Two dimensional gas turbine engine exhaust nozzle  

SciTech Connect

A two-dimensional variable area gas turbine engine exhaust nozzle is described having thrust reversing capability, the nozzle including spaced apart side wall means and upper and lower flap assemblies connected to the side wall means defining an exhaust gas flow path wihtin the nozzle, the nozzle having a centerline.

Thayer, E.B.; McLafferty, G.H.

1988-06-28

19

Exhaust gas recirculation system for an internal combustion engine  

SciTech Connect

An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

Wu, Ko-Jen

2013-05-21

20

Exhaust gas recirculation control system for internal combustion engine  

Microsoft Academic Search

An exhaust gas recirculation control system for controlling the amount of exhaust gas subjected to recirculation to the air inlet depending on the amount of inlet air of an internal combustion engine is described. This system comprises a control valve disposed in an exhaust gas recirculation passage, for controlling the amount of exhaust gas recirculation, an orifice disposed in the

T. Ito; T. Nishimiya; S. Numakura; M. Okumura

1980-01-01

21

Reduction of Fuel Consumption and Exhaust Pollutant Using Intelligent Transport Systems  

PubMed Central

Greenhouse gas emitted by the transport sector around the world is a serious issue of concern. To minimize such emission the automobile engineers have been working relentlessly. Researchers have been trying hard to switch fossil fuel to alternative fuels and attempting to various driving strategies to make traffic flow smooth and to reduce traffic congestion and emission of greenhouse gas. Automobile emits a massive amount of pollutants such as Carbon Monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2), particulate matter (PM), and oxides of nitrogen (NOx). Intelligent transport system (ITS) technologies can be implemented to lower pollutant emissions and reduction of fuel consumption. This paper investigates the ITS techniques and technologies for the reduction of fuel consumption and minimization of the exhaust pollutant. It highlights the environmental impact of the ITS application to provide the state-of-art green solution. A case study also advocates that ITS technology reduces fuel consumption and exhaust pollutant in the urban environment. PMID:25032239

Nasir, Mostofa Kamal; Md Noor, Rafidah; Kalam, M. A.; Masum, B. M.

2014-01-01

22

Exhaust gas scrubber for internal combustion engines  

Microsoft Academic Search

An exhaust gas scrubber includes a closed tank partially filled with a pool of water and a core assembly within the tank. The assembly includes a vertical cylindrical mixing tube open at its opposite ends and extending above and below water level, an upwardly opening cylindrical deflector cup at the bottom of the tank with its opening concentrically spaced within

Coyle

1981-01-01

23

SST-1 Gas feed and Gas Exhaust system  

NASA Astrophysics Data System (ADS)

SST-1 tokamak is a long pulse tokamak designed for the plasma operation up to 1000 sec duration. Gas feed system and gas exhaust management will play a very crucial role during plasma discharge. During the different type of operations of tokamak like wall conditioning, diverter operation and neutral beam injection, a large amount of gas will be fed into the vacuum chamber at different locations. Also during plasma operations, the gas will be fed both in continues and pulse mode. Gas feed will be carried out mainly using piezo-electric valves controlled by PXI based data acquisition and control system. Such operations will lead to a huge amount gas exhaust by the main system which requires good exhaust facility to searches, great care should be taken in constructing both. Also initial pumping of cryostat and vacuum vessel of SST-1 will release a large amount of gas. Exhausted gases from SST -1 will be Hydrogen, Nitrogen, Mixture gases or some toxic gases. Dedicated exhaust system controlling the different gases are installed. Special treatment of hazardous/explosive gases is done before releasing to the atmosphere. This paper describes design and implementations of the complete gas feed and exhaust system of SST-1.

Raval, Dilip C.; Khan, Ziauddin; Thankey, Prashant L.; Dhanani, Kalpesh R.; Pathan, Firozkhan S.; Semwal, Pratibha; George, Siju; Yuvakiran, Paravastu; Manthena, Himabindu; Pradhan, Subrata

2012-11-01

24

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102...Underground Coal Mines Where Permissible Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures....

2012-07-01

25

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102...Underground Coal Mines Where Permissible Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures....

2013-07-01

26

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102...Underground Coal Mines Where Permissible Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures....

2014-07-01

27

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102...Underground Coal Mines Where Permissible Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures....

2011-07-01

28

46 CFR 63.25-7 - Exhaust gas boilers.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7...MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas...

2010-10-01

29

46 CFR 63.25-7 - Exhaust gas boilers.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7...MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas...

2013-10-01

30

46 CFR 63.25-7 - Exhaust gas boilers.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7...MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas...

2012-10-01

31

Exhaust gas composition measurement. [liquid monopropellant rocket engine performance tests  

NASA Technical Reports Server (NTRS)

The design, installation, checkout, and operation of an exhaust gas composition measurement system for collecting and analyzing the exhaust gas from a liquid monopropellant rocket engine are described. Design guidelines are given for the critical components of each portion of the system to provide an exhaust gas composition measurement which meets the performance criteria specified.

1979-01-01

32

Muffler and exhaust gas purifier for internal combustion engines  

Microsoft Academic Search

An internal combustion engine exhaust gas muffler and purifier with segmented hollow shell and removable middle segment are described. The shell has an upstream exhaust gas expansion chamber, a downstream sound-absorbing and sound-collecting chamber, and a middle, removable cartridge receiving housing. The cartridge is filled with small particles of exhaust gas purifying material. 2 claims, 9 figures.

Ignoffo

1977-01-01

33

Diesel exhaust-gas purification system  

SciTech Connect

The design of a diesel exhaust gas purification system is presented. It will provide 2000 scfm of dry, anerobic gas (essentially nitrogen) for use in air drilling operations where drill pipe corrosion is a problem, such as geothermal applications. The system is operable in the field and may be transported via highways. It will operate at ambient temperatures up to 110/sup 0/F and requires no water - diesel fuel is used to combust excess oxygen and to generate electricity for the system. Gas production costs, including capital amortization, operations, fuel and maintenance (for reasonable utilization) are about $1.50/1000 scf.

Doherty, B.J.

1982-07-01

34

Exhaust gas purifying system for internal combustion engines  

Microsoft Academic Search

An exhaust gas purifying system of the type utilizing a threeway catalyst containing an oxygen storage material includes an electronic control unit for controlling the amount of secondary air supplied to the exhaust system of an internal combustion engine. The electronic control unit receives a signal from an exhaust air-fuel ratio sensor indicative of an air-fuel ratio of the exhaust

T. Hattori; K. Kondo; J. Naito; T. Nakase

1980-01-01

35

Pollutant Removal Efficiency of Residential Cooking Exhaust Hoods  

SciTech Connect

Capture efficiency (CE) of exhaust from a natural gas cooking range was quantified for three common designs of residential range hoods in laboratory experiments: (A) microwave exhaust combination; (B) short hood with grease-screen-covered air inlet at bottom; and (C) deep, open hood exhausting at top. Devices were evaluated at varying installation heights, at highest and lowest fan settings, and with the hood installed 15 cm away from back wall with intent to improve CE for front burners. Each configuration was evaluated for the oven and for three cooktop burner combinations (two back, two front, one front and one back). At highest fan settings and standard installation against the wall, Hoods A and C captured back cooktop burner exhaust at > 90 percent and Hood B at > 80 percent. In this configuration, CE for front burner exhaust was 73-78 percent for Hoods A and C but only 46-63 percent for Hood B. CEs followed similar patterns but were substantially lower on the lowest fan speed. Installing the hood away from the wall improved CE for oven and front burners on Hood A at low speed, but substantially reduced CE for back burners for all hoods at low and high speed.

Singer, Brett C.; Sherman, Alexander D.; Hotchi, Toshifumi; Sullivan, Douglas P.

2011-07-01

36

Exhaust gas recirculation in a homogeneous charge compression ignition engine  

DOEpatents

A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL)

2008-05-27

37

Real-time exhaust gas modular flowmeter and emissions reporting system for mobile apparatus  

NASA Technical Reports Server (NTRS)

A real-time emissions reporting system includes an instrument module adapted to be detachably connected to the exhaust pipe of a combustion engine to provide for flow of exhaust gas therethrough. The instrument module includes a differential pressure probe which allows for determination of flow rate of the exhaust gas and a gas sampling tube for continuously feeding a sample of the exhaust gas to a gas analyzer or a mounting location for a non-sampling gas analyzer. In addition to the module, the emissions reporting system also includes an elastomeric boot for detachably connecting the module to the exhaust pipe of the combustion engine, a gas analyzer for receiving and analyzing gases sampled within the module and a computer for calculating pollutant mass flow rates based on concentrations detected by the gas analyzer and the detected flowrate of the exhaust gas. The system may also include a particulate matter detector with a second gas sampling tube feeding same mounted within the instrument module.

Breton, Leo Alphonse Gerard (Inventor)

2002-01-01

38

40 CFR 86.1509 - Exhaust gas sampling system.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Exhaust gas sampling system. 86.1509...PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF...New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle...

2010-07-01

39

Method for treatment of a discharge liquid produced in treatment of an exhaust gas  

Microsoft Academic Search

A process is described fortreating an exhaust gas discharged from a coal combustion apparatus. The exhaust gas is first led to a dry type dust collecting device, and after fly ash in said exhaust gas is removed, said exhaust gas is treated by a wet type exhaust gas cleaning device; a part of said fly ash collected in said dry

S. Okino; A. Tatani

1981-01-01

40

Engine exhaust particulate and gas phase contributions to vascular toxicity.  

PubMed

Cardiovascular health effects of near-roadway pollution appear more substantial than other sources of air pollution. The underlying cause of this phenomenon may simply be concentration-related, but the possibility remains that gases and particulate matter (PM) may physically interact and further enhance systemic vascular toxicity. To test this, we utilized a common hypercholesterolemic mouse model (Apolipoprotein E-null) exposed to mixed vehicle emission (MVE; combined gasoline and diesel exhausts) for 6?h/d?×?50?d, with additional permutations of removing PM by filtration and also removing gaseous species from PM by denudation. Several vascular bioassays, including matrix metalloproteinase-9 protein, 3-nitrotyrosine and plasma-induced vasodilatory impairments, highlighted that the whole emissions, containing both particulate and gaseous components, was collectively more potent than MVE-derived PM or gas mixtures, alone. Thus, we conclude that inhalation of fresh whole emissions induce greater systemic vascular toxicity than either the particulate or gas phase alone. These findings lend credence to the hypothesis that the near-roadway environment may have a more focused public health impact due to gas-particle interactions. PMID:24730681

Campen, Matthew; Robertson, Sarah; Lund, Amie; Lucero, Joann; McDonald, Jacob

2014-05-01

41

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102 Mineral Resources ...Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures. (1) Follow the...

2010-07-01

42

Muffler for exhaust gas from an internal combustion engine  

Microsoft Academic Search

A muffler is described for the exhaust gas of an internal combustion engine, the muffler having an inlet and an outlet for exhaust gas and further compromising a casing and a cylindrical sound absorbing body comprising a fibrous material and extending through the casing and having an inner cylindrical surface, and a heat resistant paint formed on the inner cylindrical

H. Tanaka; M. Sekiya; F. Uchikawa

1986-01-01

43

Muffler for exhaust gas from internal combustion engine  

Microsoft Academic Search

A muffler for exhaust gas of an internal combustion engine is described comprising: (a) a casing having an inlet and an outlet for receiving an expelling, respectively, the exhaust gas, (b) a cylindrical sound-absorbing body comprising, (i) a first, perforated pipe having openings formed therein, (ii) a cylindrical porous sound-absorbing material concentrically surrounding the perforated pipe, (iii) and a thin

H. Tanaka; M. Sekiya; F. Uchikawa

1987-01-01

44

Catalyst for treating exhaust gas from an internal combustion engine  

Microsoft Academic Search

This invention is directed to an equilibrium catalyst for treating oxides of nitrogen, carbon monoxide and unburned hydrocarbons found in an exhaust gas stream from an internal combustion engine. The catalyst includes a substrate, a selective three-way equilibrium catalyst, an oxygen storage material component for maintaining the activity of the equilibrium catalyst during momentary excursions of the exhaust gas stream

H. S. Gandhi; M. Shelef

1980-01-01

45

Exhaust gas recirculation valve device for an internal combustion engine  

Microsoft Academic Search

An exhaust gas recirculation valve device is described for an exhaust gas cleaning apparatus of an internal combustion engine for an automobile. A diaphragm mechanism is mounted on a body for operating the valve device. The diaphragm mechanism has a diaphragm and has, on both sides of the diaphragm, chambers which should be connected to the respective engine ports. One

M. Ando; K. Katow; M. Yamazaki

1977-01-01

46

Muffler for exhaust gas from internal combustion engine  

Microsoft Academic Search

A muffler is described for exhaust gas of an internal combustion engine comprising, (a) a casing having an inlet and an outlet for receiving and expelling, respectively, the exhaust gas, (b) a cylindrical sound-absorbing body comprising, (i) a perforated pipe having openings formed therein, (ii) a cylindrical porous sound-absorbing material concentrically surrounding the perforated pipe, (iii) and a thin film

H. Tanaka; M. Sekiya; F. Uchikawa

1986-01-01

47

75 FR 82040 - Notice of Public Meeting on the International Maritime Organization Guidelines for Exhaust Gas...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Exhaust Gas Cleaning Systems for Marine Engines To Comply with Annex VI to MARPOL...exhaust gas cleaning systems for marine engines in Washington, DC. The purpose...exhaust gas cleaning systems for marine engines to remove sulphur oxide...

2010-12-29

48

Apparatus for reducing pollutants in engine exhaust gases  

Microsoft Academic Search

A combination thermal reactor and turbocharger apparatus for achieving improved oxidation of internal combustion engine exhausts and thus reducing hydrocarbon and carbon monoxide emissions is described. A multistage exhaust manifold thermal reactor with a turbine component interposed between two of the reactor stages receives exhaust gases from the engine exhaust manifold. The turbocharger which air-charges the cylinders of the engine

Woollenweber

1974-01-01

49

Using exhaust gas recirculation in internal combustion engines: a review  

Microsoft Academic Search

The aim of this work is to review the potential of exhaust gas recirculation (EGR) to reduce the exhaust emissions, particularly NOX emissions, and to delimit the application range of this technique. A detailed analysis of previous and current results of EGR effects on the emissions and performance of Diesel engines, spark ignition engines and duel fuel engines is introduced.

G. H. Abd-Alla

2002-01-01

50

CONTROL OF OZONE DISINFECTION BY EXHAUST GAS MONITORING  

EPA Science Inventory

In this paper it was demonstrated empirically that disinfection with ozone can be controlled by monitoring the exhaust gas ozone concentration exiting the contactor. This method is more reliable than measuring dissolved ozone because of the inherent difficulties and inadequacies ...

51

40 CFR 86.511-90 - Exhaust gas analytical system.  

Code of Federal Regulations, 2010 CFR

...chromatograph (GC) equipped with a flame ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4- dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas...

2010-07-01

52

40 CFR 86.511-90 - Exhaust gas analytical system.  

Code of Federal Regulations, 2014 CFR

...chromatograph (GC) equipped with a flame ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4- dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas...

2014-07-01

53

40 CFR 86.111-90 - Exhaust gas analytical system.  

Code of Federal Regulations, 2013 CFR

...GC) equipped with a flame ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas...

2013-07-01

54

40 CFR 86.511-90 - Exhaust gas analytical system.  

Code of Federal Regulations, 2013 CFR

...chromatograph (GC) equipped with a flame ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4- dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas...

2013-07-01

55

Measuring Carbon Monoxide in Auto Exhaust by Gas Chromatography.  

ERIC Educational Resources Information Center

Presents a simple and reliable technique using commonly available equipment for monitoring carbon monoxide in automobile exhaust. The experiment utilizes a gas chromatograph and a thermal conductivity detector (TCD). (DDR)

Jaffe, Dan; Herndon, Scott

1995-01-01

56

Gas flow means for improving efficiency of exhaust hoods  

DOEpatents

Apparatus is described for inhibiting the flow of contaminants in an exhaust enclosure toward an individual located adjacent an opening into the exhaust enclosure by providing a gas flow toward a source of contaminants from a position in front of an individual to urge said contaminants away from the individual toward a gas exit port. The apparatus comprises a gas manifold which may be worn by a person as a vest. The manifold has a series of gas outlets on a front face thereof facing away from the individual and toward the contaminants to thereby provide a flow of gas from the front of the individual toward the contaminants. 15 figures.

Gadgil, A.J.

1994-01-11

57

Method and apparatus for processing exhaust gas with corona discharge  

DOEpatents

The present invention is placing a catalyst coating upon surfaces surrounding a volume containing corona discharge. In addition, the electrodes are coated with a robust dielectric material. Further, the electrodes are arranged so that at least a surface portion of each electrode extends into a flow path of the exhaust gas to be treated and there is only exhaust gas in the volume between each pair of electrodes. 12 figs.

Barlow, S.E.; Orlando, T.M.; Tonkyn, R.G.

1999-06-22

58

40 CFR 90.420 - CVS concept of exhaust gas sampling system.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false CVS concept of exhaust gas sampling system. 90.420 Section 90.420 ...§ 90.420 CVS concept of exhaust gas sampling system. (a) A dilute exhaust sampling system is designed to directly...

2010-07-01

59

40 CFR 91.420 - CVS concept of exhaust gas sampling system.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false CVS concept of exhaust gas sampling system. 91.420 Section 91.420 ...§ 91.420 CVS concept of exhaust gas sampling system. (a) A dilute exhaust sampling system is designed to directly...

2010-07-01

60

Exhaust Gas Sensor Based On Tin Dioxide For Automotive Application  

E-print Network

Exhaust Gas Sensor Based On Tin Dioxide For Automotive Application Arthur VALLERON a,b , Christophe, Engineering Materials Department The aim of this paper is to investigate the potentialities of gas sensor layer with gold electrodes. This gas sensor is able to detect both reducing and oxidizing gases

Paris-Sud XI, Université de

61

Selective mixed potential ammonia exhaust gas sensor  

Microsoft Academic Search

Novel selective ammonia sensors with high potential for long-term stability in harsh exhaust environments are introduced. The sensor bases on the mixed potential effect. In contrast to common sensors, the electrode functionalities electrical conductivity, selective catalytic activity, and electrochemical activity combined with long-term stability are separated. For that reason, one of the two electrodes is covered by a well-known porous

Daniela Schönauer; Kerstin Wiesner; Maximilian Fleischer; Ralf Moos

2009-01-01

62

Influence of gas velocity on particulate fouling of exhaust gas recirculation coolers  

Microsoft Academic Search

The objective of this research is to study the influence of gas flow velocity on particulate fouling of exhaust gas recirculation (EGR) coolers. An experimental setup has been designed and constructed to simulate particulate fouling in EGR coolers in diesel engines. The setup consists of soot generator, gas\\/particle flow heater, testing section for EGR coolers and finally an exhaust system.

M. S. Abd-Elhady; T. Zornek; M. R. Malayeri; S. Balestrino; P. G. Szymkowicz; H. Müller-Steinhagen

2011-01-01

63

Reduction of low temperature engine pollutants by understanding the exhaust species interactions in a diesel oxidation catalyst.  

PubMed

The interactions between exhaust gas species and their effect (promotion or inhibition) on the light-off and activity of a diesel oxidation catalyst (DOC) for the removal of pollutants are studied, using actual engine exhaust gases from the combustion of diesel, alternative fuels (rapeseed methyl ester and gas-to-liquid fuel) and diesel/propane dual fuel combustion. The activity of the catalyst was recorded during a heating temperature ramp where carbon monoxide (CO) and hydrocarbon (HC) light-off curves were obtained. From the catalyst activity tests, it was found that the presence of species including CO, medium-heavy HC, alkenes, alkanes, and NOx and their concentration influence the catalyst ability to reduce CO and total HC emissions before release to the atmosphere. CO could inhibit itself and other species oxidation (e.g., light and medium-heavy hydrocarbons) while suffering from competitive adsorption with NO. Hydrocarbon species were also found to inhibit their own oxidation as well as CO through adsorption competition. On the other hand, NO2 was found to promote low temperature HC oxidation through its partial reduction, forming NO. The understanding of these exhaust species interactions within the DOC could aid the design of an efficient aftertreatment system for the removal of diesel exhaust pollutants. PMID:24450781

Lefort, I; Herreros, J M; Tsolakis, A

2014-02-18

64

Power recovery from turbine and gas engine exhausts  

SciTech Connect

Due to the energy consciousness of the United States and to the ever increasing cost of engine fuels, power recovery from turbine and gas engine exhausts has come of age. The addition of waste recovery systems to these exhausts increases the thermal efficiencies of typical systems from the range of 21% to 39% up to the range of 28% to 49%. The new ''expander'' type power recovery system includes a waste heat recovery exchanger which will transfer heat from the engine exhaust into any of numerous thermal fluids. The recovered heat energy now in the thermal fluid medium can, in turn, be used to produce power for any desired application (i.e. gas compression, process refrigeration, electrical power generation, etc.). The particular systems put forth in this paper concentrate on the use of expansion fluids (other than steam) driving ''expanders'' as motive devices.

Lawson, G.L.

1985-02-01

65

40 CFR 86.211-94 - Exhaust gas analytical system.  

Code of Federal Regulations, 2010 CFR

...Model Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.211-94 Exhaust gas analytical system. The provisions of § 86.111-94 apply to this...

2010-07-01

66

30 CFR 70.1900 - Exhaust Gas Monitoring.  

Code of Federal Regulations, 2010 CFR

... § 70.1900 Exhaust Gas Monitoring. (a) During on-shift examinations required by § 75.362, a certified person...point inby the last piece of diesel equipment on the longwall or shortwall face when mining equipment is being installed or...

2010-07-01

67

30 CFR 70.1900 - Exhaust Gas Monitoring.  

Code of Federal Regulations, 2011 CFR

... § 70.1900 Exhaust Gas Monitoring. (a) During on-shift examinations required by § 75.362, a certified person...point inby the last piece of diesel equipment on the longwall or shortwall face when mining equipment is being installed or...

2011-07-01

68

30 CFR 70.1900 - Exhaust Gas Monitoring.  

Code of Federal Regulations, 2014 CFR

... § 70.1900 Exhaust Gas Monitoring. (a) During on-shift examinations required by § 75.362, a certified person...point inby the last piece of diesel equipment on the longwall or shortwall face when mining equipment is being installed or...

2014-07-01

69

30 CFR 70.1900 - Exhaust Gas Monitoring.  

Code of Federal Regulations, 2012 CFR

... § 70.1900 Exhaust Gas Monitoring. (a) During on-shift examinations required by § 75.362, a certified person...point inby the last piece of diesel equipment on the longwall or shortwall face when mining equipment is being installed or...

2012-07-01

70

30 CFR 70.1900 - Exhaust Gas Monitoring.  

Code of Federal Regulations, 2013 CFR

... § 70.1900 Exhaust Gas Monitoring. (a) During on-shift examinations required by § 75.362, a certified person...point inby the last piece of diesel equipment on the longwall or shortwall face when mining equipment is being installed or...

2013-07-01

71

Removal of methane from compressed natural gas fueled vehicle exhaust  

Microsoft Academic Search

The objective of this paper is to investigate the modes of methane (CH[sub 4]) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the

S. Subramanian; R. J. Kudla; M. S. Chattha

1992-01-01

72

Development of titania heated exhaust-gas oxygen sensor  

Microsoft Academic Search

In this system, the composition of the engine exhaust gas must be maintained in a narrow range around the stoichiometry point to achieve high conversion efficiency for the catalyst. The closed-loop feedback control system using an oxygen sensor has been developed for this purpose. Two types of oxygen sensors have been developed: the potentiometric type using zirconia (ZrOâ) ceramic electrolyte

Takami

1988-01-01

73

Exhaust gas purifier system for internal combustion engine  

Microsoft Academic Search

A catalytic converter is mounted within an exhaust gas passage formed by a pair of tubular members each having an outwardly extending flange at their one end and connected together in tandem and in a concentric manner by means of mounting means which cooperate with the flanges. The catalytic converter includes a cylindrical, metallic shell having a pair of flanges

Aoyama

1981-01-01

74

Pollutant Removal Efficiency of Residential Cooking Exhaust Hoods  

E-print Network

for three common designs of residential range hoods in laboratory experiments: (A) microwave exhaust configuration was evaluated for the oven and for three cooktop burner combinations (two back, two front, one substantially lower on the lowest fan speed. Installing the hood away from the wall improved CE for oven

75

40 CFR 89.421 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2011 CFR

...false Exhaust gas analytical system; CVS bag sample. 89.421 Section 89.421...421 Exhaust gas analytical system; CVS bag sample. (a) Schematic drawings. ...analytical system used for analyzing CVS bag samples from compression-...

2011-07-01

76

40 CFR 89.421 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2014 CFR

...true Exhaust gas analytical system; CVS bag sample. 89.421 Section 89.421...421 Exhaust gas analytical system; CVS bag sample. (a) Schematic drawings. ...analytical system used for analyzing CVS bag samples from compression-...

2014-07-01

77

40 CFR 89.421 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2013 CFR

...false Exhaust gas analytical system; CVS bag sample. 89.421 Section 89.421...421 Exhaust gas analytical system; CVS bag sample. (a) Schematic drawings. ...analytical system used for analyzing CVS bag samples from compression-...

2013-07-01

78

40 CFR 89.421 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2010 CFR

...false Exhaust gas analytical system; CVS bag sample. 89.421 Section 89.421...421 Exhaust gas analytical system; CVS bag sample. (a) Schematic drawings. ...analytical system used for analyzing CVS bag samples from compression-...

2010-07-01

79

40 CFR 89.421 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2012 CFR

...false Exhaust gas analytical system; CVS bag sample. 89.421 Section 89.421...421 Exhaust gas analytical system; CVS bag sample. (a) Schematic drawings. ...analytical system used for analyzing CVS bag samples from compression-...

2012-07-01

80

Flight Tests of Exhaust Gas Jet Propulsion, Special Report  

NASA Technical Reports Server (NTRS)

Flight test s were conducted on the XP-41 airplane, equipped with a Pratt & Whitney R1830-19, 14-cylinder, air-cooled engine, to determine the increase in flight speed obtainable by the use of individual exhaust stacks directed rearwardly to obtain exhaust-gas thrust. Speed increases up to 18 miles per hour at 20,000 feet altitude were obtained using stacks having an exit area of 3.42 square inches for each cylinder. A slight increase in engine power and decrease in cylinder temperature at a given manifold pressure were obtained with the individual stacks as compared with a collector-ring installation. Exhaust-flame visibility was quite low, particularly in the rich range of fuel-air ratios.

Pnkel, Benjamin; Turner, L. Richard

1940-01-01

81

Integrated exhaust gas recirculation and charge cooling system  

DOEpatents

An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.

Wu, Ko-Jen

2013-12-10

82

Electron beam treatment of exhaust gas with high NOx concentration  

NASA Astrophysics Data System (ADS)

Simulated exhaust gases with a high NOx concentration, ranging from 200 to 1700 ppmv, were irradiated by an electron beam from an accelerator. In the first part of this study, only exhaust gases were treated. Low NOx removal efficiencies were obtained for high NOx concentrations, even with high irradiation doses applied. In the second part of study, gaseous ammonia or/and vapor ethanol were added to the exhaust gas before its inlet to the plasma reactor. These additions significantly enhanced the NOx removal efficiency. The synergistic effect of high SO2 concentration on NOx removal was observed. The combination of electron beam treatment with the introduction of the above additions and with the performance of irradiation under optimal parameters ensured high NOx removal efficiency without the application of a solid-state catalyst.

Licki, Janusz; Chmielewski, Andrzej G.; Pawelec, Andrzej; Zimek, Zbigniew; Witman, Sylwia

2014-05-01

83

Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine  

DOEpatents

A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

2014-05-13

84

Numerical simulation on pollutant dispersion from vehicle exhaust in street configurations  

Microsoft Academic Search

The impact of the street configurations on pollutants dispersion from vehicles exhausts within urban canyons was numerically\\u000a investigated using a computational fluid dynamics (CFD) model. Three-dimensional flow and dispersion of gaseous pollutants\\u000a were modeled using standard ????? turbulence model, which was numerically solved based on Reynolds-averaged Navier–Stokes equations by the commercial CFD code\\u000a FLUENT. The concentration fields in the urban

Mohamed F. Yassin; R. Kellnerová; Z. Ja?our

2009-01-01

85

Field test comparison of natural gas engine exhaust valves  

SciTech Connect

As part of a product improvement program, an extensive spark-ignited, turbocharged, natural gas engine exhaust valve test program was conducted using laboratory and field engines. Program objectives were to identify a valve and seat insert combination that increased mean time between overhauls (MTBO) while reducing the risk of premature valve cracking and failure. Following a thorough design review, a large number of valve and seat insert configurations were tested in a popular 900 RPM, 166 BHP (0.123 Mw) per cylinder industrial gas engine series. Material, head geometry, seat angle and other parameters were compared. Careful in-place measurements and post-test inspections compared various configurations and identified optimal exhaust valving for deployment in new units and upgrades of existing engines.

Bicknell, W.B.; Hay, S.C.; Shade, W.N.; Statler, G.R. [Cooper Cameron Corp., Springfield, OH (United States)

1996-12-31

86

Diesel Exhaust Activates & Primes Microglia: Air Pollution, Neuroinflammation, & Regulation of Dopaminergic Neurotoxicity  

EPA Science Inventory

Air pollution is linked to central nervous system (CNS) disease, but the mechanisms responsible are poorly understood. Rats exposed to Diesel Exhaust (DE, 2.0,0.5, and 0 mg/m3) by inhalation over 4 weeks demonstrated elevated levels of whole brain IL-6 protein, nitrated proteins,...

87

Cardiovascular effects of diesel exhaust and ozone in a multi-pollutant context  

EPA Science Inventory

The cardiovascular effects of two common pollutants, diesel exhaust (DE) and ozone (O3), were examined alone and in combination. Healthy subjects (n=15) were exposed for 2 hrs with intermittent, moderate exercise on Day 1 to 0.3 ppm O3, 300 µg/m3 DE, both O3 and DE, or fil...

88

Flow in non-symmetric gas turbine exhaust ducts  

NASA Astrophysics Data System (ADS)

An experimental and computational study of non-symmetric single-port gas turbine exhaust ducts has been carried out. The geometry of the exhaust duct incorporates an annular to rectangular transition with a 160° turn. The focus of the study was to determine the effect of inlet conditions and duct geometry on the flow structure and the level of overall pressure losses in the duct flow. As part of this work, the appropriateness of boundary conditions for both experimental and computational studies was investigated. The experimental studies were carried out using a ½-scale cold flow apparatus capable of measuring the flow conditions at the inlet and outlet of the duct. Inlet conditions varied included the level of swirl and circumferential total pressure distribution. Computational fluid dynamic (CFD) studies were carried out using a commercial solver using k - epsilon turbulence modeling and non-equilibrium wall functions. The computational solutions were benchmarked against experimental values, allowing CFD to be used to extend the range of inlet conditions beyond the range that could be obtained experimentally, to those more typical of an engine installation. Results show that inlet conditions have a significant effect on the flow structure in the exhaust duct. Total pressure losses in the exhaust duct increase as the circumferential inlet total pressure distribution becomes more non-uniform. This results in losses measured on a standard cold-flow apparatus under-predicting those that would exist on a duct installed on a gas turbine. However, trends in the geometric variables identified experimentally using cold flow were confirmed computationally with inlet conditions more typical of an exhaust duct mounted on an engine.

Cunningham, Mark H.

89

Exhaust gas bypass valve control for thermoelectric generator  

DOEpatents

A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter (Peter) Jacobus; Anderson, Todd Alan

2012-09-04

90

Treating exhaust gas from a pressurized fluidized bed reaction system  

DOEpatents

Hot gases from a pressurized fluidized bed reactor system are purified. Under super atmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a filtrate cake on the surface of the separator, and a reducing agent--such as an NO{sub x} reducing agent (like ammonia)--is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1--20 cm/s) during passage of the gas through the filtrate cake while at super atmospheric pressure. Separation takes place within a distinct pressure vessel, the interior of which is at a pressure of about 2--100 bar, and introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine). 8 figs.

Isaksson, J.; Koskinen, J.

1995-08-22

91

Apparatus for recovering waste heat from exhaust gas flowing through an exhaust pipe  

Microsoft Academic Search

An apparatus for recovering waste heat from a hot exhaust pipe and utilizing the heat to warm water passing through the apparatus, which comprises a plurality of thermal conduction members each longitudinally positioned in contact with said exhaust pipe, the plurality of conduction members being arranged circumferentially about the exhaust pipe, each of the thermal conduction members having a surface

Kochanowski

1983-01-01

92

Measurement of Gas-phase Acids in Diesel Exhaust  

NASA Astrophysics Data System (ADS)

Gas-phase acids were measured using chemical ionization mass spectrometry (CIMS) as part of the Diesel Engine Emission Research Experiment (DEERE). The CIMS technique, utilizing acetate ion (CH3COO-) as a reagent ion, proved to be a rapid (measurements on the order of seconds) and sensitive (several counts/pptv) method of quantifying the acid emissions. Diluted diesel exhaust measurements were made from a Constant Volume Sampling dilution tunnel using a light duty (1.9L turbocharged Volkswagen Jetta TDI) diesel engine equipped with an OEM diesel oxidation catalyst and exhaust gas recirculation, mounted on an engine dynamometer. Acids measured included isocyanic, nitrous, nitric, propionic and sum of lactic and oxalic, as well as other unidentified compounds. Complimentary measurements of CO, CO2, Total Hydrocarbon (THC), and NOx, were also performed. Several engine modes (different engine rpm and torque outputs) at steady state were examined to determine their effect on acid emissions. Emission rates with respect to NOx and fuel based emission factors were determined. Measurements of HONO fuel emission factors agree well with real-world measurements within a traffic tunnel.1 The first estimate of isocyanic acid emission factors from a diesel engine is reported, and suggests that the emission of this highly toxic compound in diesel exhaust should not be ignored. 1. Kurtenbach, R., Becker, K. H., Gomes, J. A. G., Kleffmann, J.,Lorzer, J. C., Spittler, M., Wiesen, P., Ackermann, R., Geyer, A.,and Platt, U.: Investigations of emissions and heterogeneous formation of HONO in a road traffic tunnel, Atmos. Environ., 35, 3385-3394, doi:10.1016/S1352-2310(01)00138-8, 2001.

Wentzell, J. J.; Liggio, J.; Li, S.; Vlasenko, A. L.; Staebler, R. M.; Brook, J.; Lu, G.; Poitras, M.; Chan, T.

2012-12-01

93

Exhaust gas purification apparatus for an internal combustion engine of motor vehicles  

Microsoft Academic Search

An exhaust gas purification apparatus for an internal combustion engine including a catalyst chamber containing a catalyst composition for the catalytic conversion of harmful substances contained in the exhaust gases wherein the interior wall of the exhaust pipe connecting the engine with the catalyst chamber is provided with a catalytically active coating for at least a portion of its length.

P. Oser; H. Volker

1982-01-01

94

Sensor for measuring the oxygen content in the exhaust gas of combustion engines and method thereof  

Microsoft Academic Search

An improved lambda sensor is disclosed for the measurement of the oxygen content in the exhaust gas of internal combustion engines in which the sensor element is provided with a gas permeable wrapping coated with a catalyst. The sensor delivers a clear well defined signal in the so-called rich exhaust gas, which makes possible a more precise adjustment of the

A. Bozon; E. Koberstein; H. Pletka; H. Voelker

1982-01-01

95

[Tracer gas evaluations of local exhaust hood performance].  

PubMed

A local exhaust hood is one of the most commonly used controls for harmful contaminants in the working environment. In Japan, the performance of a hood is evaluated by hood velocity measurements, and administrative performance requirements for hoods are provided as control velocities by the Japanese Industrial Safety and Health Law. However, it is doubtful whether the control velocity would be the most suitable velocity for any industrial hood since the control velocity is not substantiated by actual measurements of the containment ability of each hood. In order to examine the suitability of the control velocity as a performance requirement, a hood performance test by the tracer gas method, using carbon dioxide (CO(2)), was conducted with an exterior type hood in a laboratory. In this study, as an index of the hood performance, capture efficiency defined as the ratio of contaminant quantity captured by the hood to the total generated contaminant quantity, was determined by measuring the CO(2) concentrations. When the assumptive capture point of the contaminant was located at a point 30 cm from the hood opening, a capture efficiency of >90% could be achieved with a suction velocity of less than the current control velocity. Without cross draft, a capture efficiency of >90% could be achieved with a suction velocity of 0.2 m/s (corresponding to 40% of the control velocity) at the capture point. Reduction of the suction velocity to 0.2 m/s caused an 80% decrease in exhaust flow rate. The effect of cross draft, set at 0.3 m/s, on the capture efficiency differed according to its direction. When the direction of the cross draft was normal to the hood centerline, the effect was not recognized and a capture efficiency of >90% could be achieved with a suction velocity of 0.2 m/s. A cross draft from a worker's back (at an angle of 45 degrees to the hood centerline) did not affect the capture efficiency, either. When the cross draft blew at an angle of 135 degrees to the hood centerline, a capture efficiency of >90% could be achieved with a suction velocity of 0.4 m/s. The reduction of suction velocity would beneficially reduce running costs of local exhaust hoods and air conditioning. Effective and economical exhaustion would be achieved if the minimum velocity obtained by the tracer gas method were to be substituted for the excessive control velocity. PMID:17938560

Ojima, Jun

2007-09-01

96

Effect of stack height and exhaust velocity on pollutant dispersion in the wake of a building  

NASA Astrophysics Data System (ADS)

The dispersion of pollutants exhausted from a building roof stack located in the wake of a tower is investigated by means of the realizable k- ? turbulence model. Variations in stack height and pollutant exhaust velocity are considered to assess their influence on the distribution of pollutant concentrations in the neighbourhood of the emitting building. In order to determine optimum locations for fresh-air intakes, the worst case is considered, namely when the wind originates directly upstream of the tower and places the emitting building in its wake. Special attention is given to the evolution of the plume and distribution of pollutant concentrations on the roof and windward wall of the emitting building, as well as on the leeward wall of the upwind tower. Simulation results are compared to wind tunnel experiments conducted in a boundary layer wind tunnel. For this particular configuration, the paper shows that increasing the stack height has an effect similar to that obtained by increasing the momentum ratio, but with some differences, depending upon which wall of the two buildings is considered. On the emitting building, the leeward wall has the lowest concentration values for all stack heights and momentum ratios considered; thus this is the best location for fresh-air intakes. However, for the tower, fresh-air intakes should not be located on the leeward wall due to high pollutant concentrations. The results show completely different pollutant dispersion patterns from those for an isolated building. This highlights the importance of accounting for structures that lie in close proximity to the emitting building.

Lateb, M.; Masson, C.; Stathopoulos, T.; Bédard, C.

2011-09-01

97

Ion beam analyses of particulate matter in exhaust gas of a ship diesel engine  

NASA Astrophysics Data System (ADS)

There is an urgent need to reduce emission of the particulate matter (PM) in the exhaust gas from ship diesel engines causing various health hazards and serious environmental pollution. Usually the heavy fuel oil (HFO) for ships is of low quality, and contains various kinds of impurities. Therefore, the emission of PM along with exhaust gas from ship diesel engines is one of the most serious environmental issues. However, the PM fundamental properties are not well known. Therefore, it is important to perform elemental analysis of the PM. The HFO contains sulfur with a relatively high concentration of a few percent. It is important to make quantitative measurements of sulfur in the PM, because this element is poisonous for the human body. In the present work, PM samples were collected from exhaust gas of a test engine, and RBS and PIXE analyses were applied successfully to quantitative analysis of the PM samples. The RBS analysis enabled quantitative analysis of sulfur and carbon in the collected PM, while heavier elements such as vanadium and iron were analyzed quantitatively with the PIXE analysis. It has been found that the concentration ratio of sulfur to carbon was between 0.007 and 0.012, and did not strongly depend on the output power of the engine. The S/ C ratio is approximately equal to the original composition of the HFO used in the present work, 0.01. From the known conversion ratio 0.015 of sulfur in the HFO to sulfates, the conversion ratio of carbon in the HFO to the PM is found to be 0.01-0.02 by the RBS measurements. On the other hand, the PIXE analysis revealed a vanadium enrichment of one order of magnitude in the PM.

Furuyama, Yuichi; Fujita, Hirotsugu; Taniike, Akira; Kitamura, Akira

2011-12-01

98

Exhaust gas measurements in a propane fueled swirl stabilized combustor  

NASA Technical Reports Server (NTRS)

Exhaust gas temperature, velocity, and composition are measured and combustor efficiencies are calculated in a lean premixed swirl stabilized laboratory combustor. The radial profiles of the data between the co- and the counter swirl cases show significant differences. Co-swirl cases show evidence of poor turbulent mixing across the combustor in comparison to the counter-swirl cases. NO sub x levels are low in the combustor but substantial amounts of CO are present. Combustion efficiencies are low and surprisingly constant with varying outer swirl in contradiction to previous results under a slightly different inner swirl condition. This difference in the efficiency trends is expected to be a result of the high sensitivity of the combustor to changes in the inner swirl. Combustor operation is found to be the same for propane and methane fuels. A mechanism is proposed to explain the combustor operation and a few important characteristics determining combustor efficiency are identified.

Aanad, M. S.

1982-01-01

99

Soot filter in the exhaust gas flow of air-compressing internal combustion engines  

Microsoft Academic Search

A soot filter adapted to be arranged in an exhaust gas stream of air-compressing internal combustion engines is disclosed. The soot filter includes a cylindrical filter housing arranged in proximity of the exhaust gas stream of the internal combustion engine with inlet pipe connecting studs from outlet side of the internal combustion engine being connected to the cylindrical filter housing.

J. Abthoff; R. Gabler; H. Schuster

1980-01-01

100

30 CFR 36.43 - Determination of exhaust-gas composition.  

Code of Federal Regulations, 2012 CFR

...the volume of air (ventilation) required to dilute the exhaust gas (see § 36.45). The engine shall be at temperature equilibrium before exhaust-gas samples are collected or other test data are observed. At all test conditions the intake...

2012-07-01

101

Adaptive Air Charge Estimation for Turbocharged Diesel Engines without Exhaust Gas Recirculation  

E-print Network

Adaptive Air Charge Estimation for Turbocharged Diesel Engines without Exhaust Gas Recirculation an adaptive observer for in-cylinder air charge estimation for turbocharged diesel engines without exhaust gas (734) 764-4256 1 #12;Storset et al.- Adaptive Air Charge Est. for TC Diesel Engines 2 1 Introduction

Stefanopoulou, Anna

102

Interplay of air pollution and asthma immunopathogenesis: A focused review of diesel exhaust and ozone.  

PubMed

Controlled human exposure experiments with diesel exhaust particles (DEPs) and ozone serve to illustrate the important role pollutants play in modulating both allergic mechanisms and immune responses to affect the immunopathogenesis of airway diseases such as asthma. For DEP, evidence is stronger for the exacerbation of existing asthma rather than for the development of new disease. To the extent that this enhancement occurs, the augmentation of Th2-type immunity seems to be a common element. For ozone, neutrophilic inflammation, altered immune cell phenotype and function and oxidative stress are all marked responses that likely contribute to underlying immune-inflammatory features of asthma. Evidence is also emerging that unique gene signatures and epigenetic control of immune and inflammatory-based genes are playing important roles in the magnitude of the impact ozone is having on respiratory health. Indeed, the interplay between air pollutants such as DEP and ozone and asthma immunopathogenesis is an ongoing concern in terms of understanding how exposure to these agents can lead to worsening of disease. To this end, asthmatics may be pre-disposed to the deleterious effects of pollutants like ozone, having constitutively modified host defense functions and gene signatures. Although this review has utilized DEP and ozone as example pollutants, more research is needed to better understand the interplay between air pollution in general and asthma immumopathogenesis. PMID:25194677

Alexis, Neil E; Carlsten, Chris

2014-11-01

103

40 CFR Table 1 to Subpart Ja of... - Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents  

Code of Federal Regulations, 2014 CFR

...false Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents 1 ...Part 60—Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents Constituent...F and 1 atmosphere. b MHC = molar heat content (higher heating value...

2014-07-01

104

40 CFR Table 1 to Subpart Ja of... - Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents  

Code of Federal Regulations, 2013 CFR

...false Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents 1 ...Part 60—Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents Constituent...F and 1 atmosphere. b MHC = molar heat content (higher heating value...

2013-07-01

105

Glutathione peroxidase inhibitory assay for electrophilic pollutants in diesel exhaust and tobacco smoke  

PubMed Central

We developed a rapid kinetic bioassay demonstrating the inhibition of glutathione peroxidase 1 (GPx-1) by organic electrophilic pollutants such as acrolein, crotonaldehyde, and p-benzoquinone that are frequently found as components of tobacco smoke, diesel exhaust, and other combustion sources. In a complementary approach, we applied a high-resolution proton-transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) to monitor in real-time the generation of electrophilic volatile carbonyls in cigarette smoke. The new bioassay uses the important antioxidant selenoenzyme GPx-1, immobilized to 96-well microtiter plates, as a probe. The selenocysteine bearing subunits of the enzyme's catalytic site are viewed as cysteine analogues and are vulnerable to electrophilic attack by compounds with conjugated carbonyl systems. The immobilization of GPx-1 to microtiter plate wells enabled facile removal of excess reactive inhibitory compounds after incubation with electrophilic chemicals or aqueous extracts of air samples derived from different sources. The inhibitory response of cigarette smoke and diesel exhaust particle extracts were compared to chemical standards of a group of electrophilic carbonyls and the arylating p-benzoquinone. GPx-1 activity was directly inactivated by millimolar concentrations of highly reactive electrophilic chemicals (including acrolein, glyoxal, methylglyoxal, and p-benzoquinone) and extracts of diesel and cigarette smoke. We conclude that the potential of air pollutant components to generate oxidative stress may be, in part, a result of electrophile-derived covalent modifications of enzymes involved in the cytosolic antioxidant defense. PMID:22349402

Staimer, Norbert; Nguyen, Tran B.; Nizkorodov, Sergey A.; Delfino, Ralph J.

2012-01-01

106

Numerical simulation on pollutant dispersion from vehicle exhaust in street configurations.  

PubMed

The impact of the street configurations on pollutants dispersion from vehicles exhausts within urban canyons was numerically investigated using a computational fluid dynamics (CFD) model. Three-dimensional flow and dispersion of gaseous pollutants were modeled using standard kappa - epsilon turbulence model, which was numerically solved based on Reynolds-averaged Navier-Stokes equations by the commercial CFD code FLUENT. The concentration fields in the urban canyons were examined in three cases of street configurations: (1) a regular-shaped intersection, (2) a T-shaped intersection and (3) a Skew-shaped crossing intersection. Vehicle emissions were simulated as double line sources along the street. The numerical model was validated against wind tunnel results in order to optimize the turbulence model. Numerical predictions agreed reasonably well with wind tunnel results. The results obtained indicate that the mean horizontal velocity was very small in the center near the lower region of street canyon. The lowest turbulent kinetic energy was found at the separation and reattachment points associated with the corner of the down part of the upwind and downwind buildings in the street canyon. The pollutant concentration at the upwind side in the regular-shaped street intersection was higher than that in the T-shaped and Skew-shaped street intersections. Moreover, the results reveal that the street intersections are important factors to predict the flow patterns and pollutant dispersion in street canyon. PMID:18726702

Yassin, Mohamed F; Kellnerová, R; Janour, Z

2009-09-01

107

Engine exhaust control system and method  

SciTech Connect

This patent describes an exhaust gas control apparatus for an internal combustion engine. It comprises: a rotary fan blade assembly having a hollow hub and plurality of hollow blades, each having a plurality of apertures in a trailing edge; drive means for driving the rotary fan blade assembly; feed means feeding exhaust gases from the engine into the hollow hub and hollow blades; air intake means for feeding intake air to the rotary fan blade assembly from a direction opposite to the direction of flow of the exhaust gases into the hollow hub of the rotary fan blade assembly; exhaust means for exhausting a mixture of air and the exhaust gases; whereby the flow of exhaust gases through the rotary fan blade assembly and out through the exhaust means reduces back-pressure, exhaust noise, exhaust temperature and exhaust pollutants.

Billington, W.G.

1990-04-03

108

Estimating IC engine exhaust gas lambda and oxygen from the response of a universal exhaust gas oxygen sensor  

NASA Astrophysics Data System (ADS)

Universal exhaust gas oxygen sensors (UEGOs) are in widespread use in internal combustion engines where they are used to measure lambda (the non-dimensional air-fuel ratio) and oxygen concentration (X_{O_2 }). The sensors are used on production engines and for research and development. In a previous paper, a model of the UEGO sensor was presented, based on a solution of the Stefan-Maxwell equations for an axisymmetric geometry, and it was shown that for a known gas composition, predictions of the sensor response agreed well with experiment. In the present paper, the more ‘practical’ problem is addressed: how well can such a model predict ? and X_{O_2 } based on the sensor response? For IC engine applications, a chemistry model is required in order to predict ?, and such a model is also desirable for an accurate prediction of X_{O_2 }. A fast (matrix exponential) method of solving the Stefan-Maxwell equations is also introduced, which offers the possibility of a near real-time computation of ? and X_{O_2 }, with application, for example, to bench instruments. Extensive results are presented showing how the interpretation of the UEGO response may be compromised by uncertainties. These uncertainties may relate not only to the sensor itself, such as temperature, pressure and mean pore diameter, but also the chemistry model.

Collings, N.; Harris, J. A.; Glover, K.

2013-09-01

109

Supervision and control prototyping for an engine exhaust gas heat recovery system based on a steam Rankine cycle  

E-print Network

Supervision and control prototyping for an engine exhaust gas heat recovery system based on a steam Rankine steam process for exhaust gas heat recovery from a spark-ignition (SI) engine, from a prototyping of a practical supervi- sion and control system for a pilot Rankine steam process for exhaust gas heat recovery

Paris-Sud XI, Université de

110

Exhaust gas fuel reforming of Diesel fuel by non-thermal arc discharge for NOx trap regeneration  

E-print Network

to the reforming of Diesel fuel with Diesel engine exhaust gas using a non-thermal plasma torch for NOx trap and Fuels 25, 3 (2011) 1034-1044" DOI : 10.1021/ef101674r #12;2 Diesel engine exhaust gas are reported-heptane as surrogate molecule for Diesel fuel. Two compositions of synthetic Diesel engine exhaust gas, corresponding

Boyer, Edmond

111

On the thermodynamics of waste heat recovery from internal combustion engine exhaust gas  

NASA Astrophysics Data System (ADS)

The ideal internal combustion (IC) engine (Otto Cycle) efficiency ?IC= 1-(1/r)^(?-1) is only a function of engine compression ratio r=Vmax/Vmin and exhaust gas specific heat ratio ?= cP/cV. Typically r= 8, ?= 1.4, and ?IC= 56%. Unlike the Carnot Cycle where ?Carnot= 1-(TC/TH) for a heat engine operating between hot and cold heat reservoirs at TH and TC, respectively, ?IC is not a function of the exhaust gas temperature. Instead, the exhaust gas temperature depends only on the intake gas temperature (ambient), r, ?, cV, and the combustion energy. The ejected exhaust gas heat is thermally decoupled from the IC engine and conveyed via the exhaust system (manifold, pipe, muffler, etc.) to ambient, and the exhaust system is simply a heat engine that does no useful work. The maximum fraction of fuel energy that can be extracted from the exhaust gas stream as useful work is (1-?IC) x?Carnot= 32% for TH= 850 K (exhaust) and TC= 370 K (coolant). This waste heat can be recovered using a heat engine such as a thermoelectric generator (TEG) with ?TEG0 in the exhaust system. A combined IC engine and TEG system can generate net useful work from the exhaust gas waste heat with efficiency ?WH= (1-?IC) x?Carnot x?TEG, and this will increase the overall fuel efficiency of the total system. Recent improvements in TEGs yield ?TEG values approaching 15% giving a potential total waste heat conversion efficiency of ?WH= 4.6%, which translates into a fuel economy improvement approaching 5%.

Meisner, G. P.

2013-03-01

112

Method for controlling exhaust gas heat recovery systems in vehicles  

DOEpatents

A method of operating a vehicle including an engine, a transmission, an exhaust gas heat recovery (EGHR) heat exchanger, and an oil-to-water heat exchanger providing selective heat-exchange communication between the engine and transmission. The method includes controlling a two-way valve, which is configured to be set to one of an engine position and a transmission position. The engine position allows heat-exchange communication between the EGHR heat exchanger and the engine, but does not allow heat-exchange communication between the EGHR heat exchanger and the oil-to-water heat exchanger. The transmission position allows heat-exchange communication between the EGHR heat exchanger, the oil-to-water heat exchanger, and the engine. The method also includes monitoring an ambient air temperature and comparing the monitored ambient air temperature to a predetermined cold ambient temperature. If the monitored ambient air temperature is greater than the predetermined cold ambient temperature, the two-way valve is set to the transmission position.

Spohn, Brian L.; Claypole, George M.; Starr, Richard D

2013-06-11

113

Chemical Gas Sensors for Car Exhaust and Cabin Air Monitoring  

Microsoft Academic Search

A combination of charcoal and particle filters has previously been shown to reduce effectively the smell of diesel exhaust. In this paper it is shown that the smell of diesel exhaust can successfully be predicted by the concentration of total volatile organic compounds and the concentration of certain carbonyl compounds. Projection to latent structures was utilised for model building. An

Eva-Lotta Kalman; Fredrik Winquist; Anders Löfvendahl; Bertil Rudell; Urban Wass

2002-01-01

114

Chemical Gas Sensors for Car Exhaust and Cabin Air Monitoring  

Microsoft Academic Search

A combination of charcoal and particle filters has pre viously been shown to reduce effectively the smell of diesel exhaust. In this paper it is shown that the smell of diesel exhaust can successfully be predicted by the con centration of total volatile organic compounds and the concentration of certain carbonyl compounds. Projection to latent structures was utilised for model

Eva-Lotta Kalman; Fredrik Winquist; Anders Löfvendahl; Bertil Rudell; Urban Wass

2002-01-01

115

Exhaust gas purifying device for internal combustion engine  

Microsoft Academic Search

An oxygen sensor is disposed upstream of a three-way catalyst in an exhaust system of an internal combustion engine and includes a sensing element of metal oxide whose electromotive force or resistance value varies in response to the concentration of oxygen in the engine exhaust gases. A catalytic body including a catalytic metal material exhibiting the same catalytic performance as

M. Asano; K. Kondo; Y. Segawa

1981-01-01

116

Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review  

NASA Astrophysics Data System (ADS)

Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.

Masiol, Mauro; Harrison, Roy M.

2014-10-01

117

Knock mitigation on boosted Controlled Auto-Ignition engines with fuel stratification and Exhaust Gas Recycling  

E-print Network

This research is carried out to understand the mechanism of using fuel stratification and Exhaust Gas Recycling (EGR) for knock mitigation on boosted Controlled Auto-Ignition (CAl) engines. Experiments were first conducted ...

Sang, Wen, Ph. D. Massachusetts Institute of Technology

2014-01-01

118

40 CFR 86.209-94 - Exhaust gas sampling system; gasoline-fueled vehicles.  

Code of Federal Regulations, 2010 CFR

...Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.209-94 Exhaust gas sampling system; gasoline-fueled vehicles. The provisions of §...

2010-07-01

119

40 CFR 91.423 - Exhaust gas analytical system; CVS grab sample.  

Code of Federal Regulations, 2010 CFR

...hydrocarbons, nondispersive infrared analyzers (NDIR) for the measurement of carbon monoxide and carbon dioxide, and a chemiluminescence detector (CLD) (or heated CLD (HCLD)) for the measurement of oxides of nitrogen. The exhaust gas...

2010-07-01

120

40 CFR 90.423 - Exhaust gas analytical system; CVS grab sample.  

Code of Federal Regulations, 2010 CFR

...non-dispersive infrared analyzers (NDIR) for the measurement of carbon monoxide and carbon dioxide, and a chemiluminescence detector (CLD) (or heated CLD (HCLD)) for the measurement of oxides of nitrogen. The exhaust gas...

2010-07-01

121

30 CFR 36.47 - Tests of exhaust-gas cooling system.  

Code of Federal Regulations, 2014 CFR

...compartments designed to hold cooling water shall be filled with the quantity...performance of the system, the cooling water consumption, high-water level...temperature is lower. (d) Water consumed in cooling the exhaust gas under the...

2014-07-01

122

30 CFR 36.47 - Tests of exhaust-gas cooling system.  

Code of Federal Regulations, 2013 CFR

...compartments designed to hold cooling water shall be filled with the quantity...performance of the system, the cooling water consumption, high-water level...temperature is lower. (d) Water consumed in cooling the exhaust gas under the...

2013-07-01

123

30 CFR 36.47 - Tests of exhaust-gas cooling system.  

Code of Federal Regulations, 2011 CFR

...compartments designed to hold cooling water shall be filled with the quantity...performance of the system, the cooling water consumption, high-water level...temperature is lower. (d) Water consumed in cooling the exhaust gas under the...

2011-07-01

124

30 CFR 36.47 - Tests of exhaust-gas cooling system.  

Code of Federal Regulations, 2012 CFR

...compartments designed to hold cooling water shall be filled with the quantity...performance of the system, the cooling water consumption, high-water level...temperature is lower. (d) Water consumed in cooling the exhaust gas under the...

2012-07-01

125

30 CFR 36.47 - Tests of exhaust-gas cooling system.  

Code of Federal Regulations, 2010 CFR

...performance of the system, the cooling water consumption, high-water level when the system sprays excess water, and low-water level when the cooling system fails. (c) The final exhaust-gas temperature at discharge from the cooling...

2010-07-01

126

30 CFR 36.43 - Determination of exhaust-gas composition.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS...DIESEL-POWERED TRANSPORTATION EQUIPMENT Test Requirements § 36...the safe operation of diesel equipment. (b) Exhaust-gas...complete with all component equipment such as air cleaners,...

2010-07-01

127

30 CFR 36.43 - Determination of exhaust-gas composition.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS...DIESEL-POWERED TRANSPORTATION EQUIPMENT Test Requirements § 36...the safe operation of diesel equipment. (b) Exhaust-gas...complete with all component equipment such as air cleaners,...

2014-07-01

128

30 CFR 36.43 - Determination of exhaust-gas composition.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS...DIESEL-POWERED TRANSPORTATION EQUIPMENT Test Requirements § 36...the safe operation of diesel equipment. (b) Exhaust-gas...complete with all component equipment such as air cleaners,...

2013-07-01

129

30 CFR 36.43 - Determination of exhaust-gas composition.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS...DIESEL-POWERED TRANSPORTATION EQUIPMENT Test Requirements § 36...the safe operation of diesel equipment. (b) Exhaust-gas...complete with all component equipment such as air cleaners,...

2011-07-01

130

Design review report for the RMCS exhauster modifications for flammable gas tanks  

SciTech Connect

This report documents the completion of the formal design review for the Rotary Mode Core Sampling (RMCS) Exhauster modifications for flammable gas tanks. The RMCS Exhauster modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to approve Engineering Change Orders and new drawings, at the 100% design completion state. The conclusion reached by the review committee was that the design was acceptable and efforts should continue toward fabrication and delivery.

Corbett, J.E., Westinghouse Hanford

1996-08-27

131

Surface gas pollutants in Lhasa, a highland city of Tibet - current levels and pollution implications  

NASA Astrophysics Data System (ADS)

Through several years of development, the city of Lhasa has become one of the most populated and urbanized areas on the highest plateau in the world. In the process of urbanization, current and potential air quality issues have been gradually concerned. To investigate the current status of air pollution in Lhasa, various gas pollutants including NOx, CO, SO2, and O3, were continuously measured from June 2012 to May 2013 at an urban site (29.40° N, 91.08° E, 3650 m a.s.l.). The seasonal variations of primary gas pollutants exhibited a peak from November to January with a large variability. High mixing ratios of primary trace gases almost exclusively occurred under low wind speed and showed no distinct dependence on wind direction, implying local urban emissions to be predominant. A comparison of NO2, CO, and SO2 mixing ratios in summer between 1998 and 2012 indicated a significant increase in emissions of these gas pollutants and a change in their intercorrelations, as a result of a substantial growth in the demand of energy consumption using fossil fuels instead of previously widely used biomass. The pronounced diurnal double peaks of primary trace gases in all seasons suggested automobile exhaust to be a major emission source in Lhasa. The secondary gas pollutant O3 displayed an average diurnal cycle of a shallow flat peak for about 4-5 h in the afternoon and a minimum in the early morning. Nighttime O3 was sometimes completely consumed by the high level of NOx. Seasonally, the variations of O3 mixing ratios displayed a low valley in winter and a peak in spring. In autumn and winter, transport largely contributed to the observed O3 mixing ratios, given its dependence on wind speed and wind direction, while in spring and summer photochemistry played an important role. A more efficient buildup of O3 mixing ratios in the morning and a higher peak in the afternoon was found in summer 2012 than in 1998. An enhancement in O3 mixing ratios would be expected in the future and more attention should be given to O3 photochemistry in response to increasing precursor emissions in this area.

Ran, L.; Lin, W. L.; Deji, Y. Z.; La, B.; Tsering, P. M.; Xu, X. B.; Wang, W.

2014-10-01

132

Surface gas pollutants in Lhasa, a highland city of Tibet: current levels and pollution implications  

NASA Astrophysics Data System (ADS)

Through several years of development, the city of Lhasa has become one of the most populated and urbanized areas on the highest plateau in the world. In the process of urbanization, current and potential air quality issues have been gradually concerned. To investigate the current status of air pollution in Lhasa, various gas pollutants including NOx, CO, SO2 and O3 were continuously measured from June 2012 to May 2013 at an urban site (29.40° N, 91.08° E, 3650 m a.s.l.). The seasonal variations of primary gas pollutants exhibited a peak from November to January with a large variability. High concentrations of primary trace gases almost exclusively occurred under low wind speed and showed no distinct dependence on wind direction, implying local urban emissions to be predominant. A comparison of NO2, CO and SO2 concentrations in summer between 1998 and 2012 indicated a significant increase in emissions of these gas pollutants and a change in their intercorrelations, as a result of a substantial growth in the demand of energy consumption using fossil fuels instead of previously widely used biofuels. The pronounced diurnal double peaks of primary trace gases in all seasons suggested automobile exhaust to be a major emission source in Lhasa. The secondary gas pollutant O3 displayed an average diurnal cycle of a shallow flat peak for about 4-5 h in the afternoon and a minimum in the early morning. Nighttime O3 was sometimes completely consumed by the high level of NOx. Seasonally, the variations of O3 concentrations displayed a low valley in winter and a peak in spring. In autumn and winter, transport largely contributed to the observed O3 concentrations, given its dependence on wind speed and wind direction, while in spring and summer photochemistry played an important role. A more efficient buildup of O3 concentrations in the morning and a higher peak in the afternoon was found in summer 2012 than in 1998. An enhancement in O3 concentrations would be expected in the future and more attention should be given to O3 photochemistry in response to increasing precursor emissions in this area.

Ran, L.; Lin, W. L.; Deji, Y. Z.; La, B.; Tsering, P. M.; Xu, X. B.; Wang, W.

2014-05-01

133

Use of exhaust gas as sweep flow to enhance air separation membrane performance  

DOEpatents

An intake air separation system for an internal combustion engine is provided with purge gas or sweep flow on the permeate side of separation membranes in the air separation device. Exhaust gas from the engine is used as a purge gas flow, to increase oxygen flux in the separation device without increasing the nitrogen flux.

Dutart, Charles H. (Washington, IL); Choi, Cathy Y. (Morton, IL)

2003-01-01

134

Pollution control catalyst for internal combustion engine exhaust system\\/catalytic converter and process for its preparation  

Microsoft Academic Search

A pollution control catalyst for a catalytic converter within the exhaust system of an internal combustion engine is facilely prepared by coating\\/impregnating a catalyst support with palladium and at least one base metal catalyst, activating the step catalyst, next coating\\/impregnating the step activated catalyst with at least one platinum group precious metal other than palladium, or combination of palladium and

G. Blanchard; J. P. Brunelle; M. Prigent

1985-01-01

135

Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow  

DOEpatents

An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

Orosa, John

2014-03-11

136

Control method for turbocharged diesel engines having exhaust gas recirculation  

DOEpatents

A method of controlling the airflow into a compression ignition engine having an EGR and a VGT. The control strategy includes the steps of generating desired EGR and VGT turbine mass flow rates as a function of the desired and measured compressor mass airflow values and exhaust manifold pressure values. The desired compressor mass airflow and exhaust manifold pressure values are generated as a function of the operator-requested fueling rate and engine speed. The EGR and VGT turbine mass flow rates are then inverted to corresponding EGR and VGT actuator positions to achieve the desired compressor mass airflow rate and exhaust manifold pressure. The control strategy also includes a method of estimating the intake manifold pressure used in generating the EGR valve and VGT turbine positions.

Kolmanovsky, Ilya V. (Ypsilanti, MI); Jankovic, Mrdjan J (Birmingham, MI); Jankovic, Miroslava (Birmingham, MI)

2000-03-14

137

Suicide by carbon monoxide from car exhaust-gas in Denmark 1995-1999.  

PubMed

In the period 1995-1999 there were 388 car exhaust-gas suicides in Denmark. Of these 343 (88.4%) were men and 45 (11.6%) were women, the average age being 47 years. The car exhaust-gas suicides made up 9.3% of all suicides in Denmark in the period. The corresponding rate was 11.7% for men and 3.7% for women. In rural areas a larger part of all suicides were committed with car exhaust-gas compared to the more densely populated areas. Mental disease was diagnosed in 124 (32.0%) cases. A suicide note was found in 165 (42.5%) cases. A hose was fitted to the exhaust pipe in 334 (86.1%) cases. Of these the 234 (60.3%) occurred outside, typically in a forest area, while 76 (19.6%) occurred in a closed garage. All the 54 (13.9%) cases with no hose fitted to the exhaust pipe occurred in a garage. Seven (1.8%) victims were found in a burning or burnt-out car, where the following investigation revealed that it was actually a car exhaust-gas suicide. Carboxyhemoglobin was measured in 26 (6.7%) victims. In two of these victims no carboxyhemoglobin was found, as they had survived for some time after the poisoning. The average saturation of the remaining victims was 67%, the lowest saturation being 20% and the highest being 84%. In the period 1969-1987 the number of car exhaust-gas suicides in Denmark increased from 50 to approximately 190 per year and the rate of car exhaust-gas suicides compared to all suicides increased from approximately 5% to approximately 13%. In 1987-1999 these figures decreased from approximately 190 to 63 per year and from 13% to approximately 8%. During these 30 years the number of passenger cars in Denmark doubled, which explains the increase in car exhaust-gas suicides during 1969-1987. A possible explanation for the decrease in 1987-1999 is the introduction of the catalytic converter, which was made mandatory in 1990. We anticipate that car exhaust-gas suicides will continue to decrease in numbers, as more cars are equipped with catalytic converters. PMID:16310328

Thomsen, Asser H; Gregersen, Markil

2006-08-10

138

40 CFR 86.1511 - Exhaust gas analysis system.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL...Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle...Methanol-Fueled Natural Gas-Fueled, and Liquefied...7) The interference gases listed shall...

2010-07-01

139

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOEpatents

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2002-01-01

140

Identification, structure elucidation, and synthesis of volatile compounds in the exhaust gas of food factories.  

PubMed

Our investigations deal with the identification and synthesis of volatile, odoriferous compounds contained in the exhaust gas of food factories and on the biodegradation of alkylpyrazines. Collection of odour emissions samples was performed with a gas sampler equipped with filter tubes containing the styrene-polymer SuperQ. After elution with solvents of different polarity, the extracts were analysed by GC/MS and chemical microreactions. Proposed structures were verified by comparison of analytical data with those of synthetic reference samples. Major components in the exhaust gas of a fat finishing factory were found to be aliphatic aldehydes, strongly dominated by hexanal. The identification of 1,2,3,3-tetramethylcyclohexene shows that for structural proof of target compounds the use of authentic reference samples is indispensable. In the exhaust gas from a chocolate factory, several carbonyl compounds and alkylated pyrazines could be identified. Biodegradation of the latter starts with hydrogenation at the nucleus. PMID:16154731

Nagorny, S; Francke, W

2005-01-01

141

Sync-ring assembly for a gas turbine engine exhaust nozzle  

Microsoft Academic Search

A sync-ring assembly is described for selectively positioning divergent flap of a gas turbine engine exhaust nozzle relative to the exhaust nozzle's case, the nozzle having a centerline defined there through, the assembly comprising: a sync-ring pivotably connected to the divergent flaps by a plurality of positioning strut assemblies, the sync-ring having a first surface and a second surface radially

Barcza

1993-01-01

142

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOEpatents

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime (about 40 ps), high frequency (about 5G hz), high power bursts of low-duty factor microwaves sufficient to generate a dielectric barrier discharge and passing a gas to treated through the discharge so as to cause dissociative reduction of the exhaust gases. The invention also includes a reactor for generating the non-thermal plasma.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Upsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2001-01-01

143

A ceramic heat exchanger for exhaust fired gas turbine power cycles  

Microsoft Academic Search

Until recently, combustion of solid fuels such as forest product residues, municipal waste, or coal in gas turbine power cycles has been limited by the corrosive action of the combustion products. A heat exchanger which can operate in this corrosive environment has been developed, making the exhaust fired gas turbine an economically viable power source. This heat exchanger is fabricated

I. G. Most; K. G. Hagen

1977-01-01

144

Diesel emission reduction using internal exhaust gas recirculation  

SciTech Connect

A method for controlling combustion in a direct-injection diesel engine includes monitoring a crankshaft rotational position of a cylinder of the engine, monitoring an engine load, determining an intake stroke within the cylinder based upon the crankshaft rotational position, and when the engine load is less than a threshold engine load, opening an exhaust valve for the cylinder during a portion of the intake stroke.

He, Xin (Denver, CO); Durrett, Russell P. (Bloomfield Hills, MI)

2012-01-24

145

Exhaust gas recirculation control method and apparatus for internal combustion engine  

SciTech Connect

An exhaust gas recirculation control method is described for operating an exhaust gas recirculation control device including a needle valve provided in an exhaust gas recirculation passage for setting an effective diameter of the passage, a position sensor for providing a signal representing a position of the needle valve, and a negative pressure motor for positioning the needle valve. The method comprises: setting a target value for the needle valve according to predetermined operating conditions of the internal combustion engine; measuring a positional deviation between the target value and an actual position of the needle valve as represented by the signal provided by the position sensor; and driving the negative pressure motor with only a single drive pulse having a time width corresponding to the measured positional deviation. An exhaust gas recirculation control apparatus is described for operating an exhaust gas recirculation control device. The apparatus comprises: means for setting a target value for the needle valve according to predetermined operating conditions of the internal combustion engine; and means for measuring a positional deviation between the target value and an actual position of the needle valve as represented by the signal provided by the position sensor.

Tsutsumi, K.

1987-02-10

146

Thermoelectric exhaust-gas energy recovery: An integrated approach  

NASA Astrophysics Data System (ADS)

Here we describe the first results from an interdisciplinary project that seeks to develop a skutterudite-based thermoelectric (TE) energy recovery system for a vehicle exhaust stream. Filled skutterudites have been prepared and characterised and their thermal stability evaluated. Thermoelements fabricated from these skutterudites have been used to evaluate the compatibility of materials required for the construction of TE modules. The results of modelling studies for the optimization of heat exchanger design and the creation of a component in the loop test facility are also described.

Powell, A. V.; Kaltzoglou, A.; Vaqueiro, P.; Min, G.; Garcia-Cañadas, J.; Stobart, R. K.; Li, J.; Dong, G.; Wijewardane, A.

2012-06-01

147

Experimental study on engine gas-path component fault monitoring using exhaust gas electrostatic signal  

NASA Astrophysics Data System (ADS)

This paper presents the recent development in engine gas-path components health monitoring using electrostatic sensors in combination with signal-processing techniques. Two ground-based engine electrostatic monitoring experiments are reported and the exhaust gas electrostatic monitoring signal-based fault-detection method is proposed. It is found that the water washing, oil leakage and combustor linear cracking result in an increase in the activity level of the electrostatic monitoring signal, which can be detected by the electrostatic monitoring system. For on-line health monitoring of the gas-path components, a baseline model-based fault-detection method is proposed and the multivariate state estimation technique is used to establish the baseline model for the electrostatic monitoring signal. The method is applied to a data set from a turbo-shaft engine electrostatic monitoring experiment. The results of the case study show that the system with the developed method is capable of detecting the gas-path component fault in an on-line fashion.

Sun, Jianzhong; Zuo, Hongfu; Liu, Pengpeng; Wen, Zhenhua

2013-12-01

148

Fast exhaust channel optical absorption method and apparatus to study the gas exchange in large diesel engines  

NASA Astrophysics Data System (ADS)

An optical absorption spectroscopic method and apparatus with shorter than 1 ms response time have been used to study the gas exchange processes in realistic conditions for a single cylinder of a large diesel engine. The method is based on measuring the differential line-of-sight optical uv absorption of the exhaust-gas-contained SO2 as a function of time in the exhaust port area just after the exhaust valves. The optical absorption by SO2 is determined from light transmission measurements at 280 and 340 nm performed through optical probes installed into the exhaust channel wall. The method has been applied to a continuously fired, large, medium speed production-line-type diesel engine with 990 kW rated power. The test engine was operated with standard light fuel oil (MDO Termoshell) and with light fuel oil treated with a sulfur additive {Di-Tert-Butyldisulfid [(CH3)3C]2S2}. The latter was to improve the optical absorption signals without increasing the fouling of the exhaust channel optical probes as in the case of heavier fuel oil qualities. In the reported case of a four-stroke diesel engine measurement results show that the method can provide time-resolved information of the SO2 density in the exhaust channel and thus give information on the single-cylinder gas exchange. During the inlet and exhaust valve overlap period the moment of fresh air entering into the measurement volume can be detected. If independent exhaust gas temperature and pressure data are available, the absorption measurements can readily be used for determining the burnt gas fraction in the exhaust channel. In this work the possibility of using the optical absorption measurement to determine the instaneous exhaust gas temperature was studied. Based on known fuel properties and conventional averaged SO2 measurements from the exhaust channel a known concentration of SO2 was assumed in the exhaust gas after the exhaust valves opening and before the inlet and exhaust valves overlap period. Together with an exhaust gas pressure measurement the optical absorption signal was used to determine the instaneous exhaust gas temperature. Due to the minimal modifications needed by the engine for optical access, and continuously fired operation with relevant power levels and realistic fuel qualities, this measurement method, with some further development, can be useful to obtain time-resolved data from the exhaust channel of real production-line-type diesel engines.

Vattulainen, J.; Hernberg, R.; Hattar, C.; Gros, S.

1998-01-01

149

AUTOMOTIVE EXHAUST AND MOUSE ACTIVITY: RELATIONSHIPS BETWEEN POLLUTANT CONCENTRATIONS AND DECREASES IN WHEEL RUNNING  

EPA Science Inventory

Groups of male and female mice inhaled either clean air, 100 ppm carbon monoxide, or light-irradiated and nonirridiated automotive exhaust containing nominally 25, 50, 75, or 100 ppm carbon monoxide in three tests with exposure lasting from 4 to 7 days. Exhaust from a factory or ...

150

40 CFR 86.111-94 - Exhaust gas analytical system.  

Code of Federal Regulations, 2013 CFR

...for formaldehyde is performed using high-pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine (DNPH) derivatives...Recommended Practice J1151, “Methane Measurement Using Gas Chromatography,” December 1991, 1994 SAE Handbook—SAE...

2013-07-01

151

40 CFR 86.111-94 - Exhaust gas analytical system.  

Code of Federal Regulations, 2011 CFR

...for formaldehyde is performed using high-pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine (DNPH) derivatives...Recommended Practice J1151, “Methane Measurement Using Gas Chromatography,” December 1991, 1994 SAE Handbook—SAE...

2011-07-01

152

40 CFR 86.111-94 - Exhaust gas analytical system.  

Code of Federal Regulations, 2012 CFR

...for formaldehyde is performed using high-pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine (DNPH) derivatives...Recommended Practice J1151, “Methane Measurement Using Gas Chromatography,” December 1991, 1994 SAE Handbook—SAE...

2012-07-01

153

DESIGN AND CHARACTERIZATION OF AN ISOKINETIC SAMPLING TRAIN FOR PARTICLE SIZE MEASUREMENTS USING EXHAUST GAS RECIRCULATION  

EPA Science Inventory

A particulate sampling train has been constructed which satisfies the conflicting requirements of isokinetic sample extraction and constant flowrate through an inertial sizing device. Its design allows a variable fraction of the filtered exhaust gas to be added to the sample upst...

154

Investigation of the electrode effects in mixed potential type ammonia exhaust gas sensors  

Microsoft Academic Search

Mixed potential ammonia exhaust gas sensors provide a high capability for applications in harsh environments when appropriate means are conducted to stabilize the electrodes catalytic activity. The discussed sensor utilizes oxygen ion conducting yttria stabilized zirconia and gold electrodes, one of which is covered with an SCR active film to establish ammonia sensitivity and selectivity. The used SCR catalyst is

Daniela Schönauer; Thomas Nieder; Kerstin Wiesner; Maximilian Fleischer; Ralf Moos

2011-01-01

155

Waste heat recovery using heat pipe heat exchanger for heating automobile using exhaust gas  

Microsoft Academic Search

The feasibility of using heat pipe heat exchangers for heating applying automotive exhaust gas is studied and the calculation method is developed. Practical heat pipe heat exchanger is set up for heating HS663, a large bus. Simple experiments are carried out to examine the performance of the heat exchanger. It is shown that the experimental results, which indicate the benefit

Feng Yang; Xiugan Yuan; Guiping Lin

2003-01-01

156

Effect of periodic operation over Pt catalysts in simulated oxidizing exhaust gas  

Microsoft Academic Search

The effect of periodic operation over Pt and Pt\\/Ba catalysts supported on ?-alumina under oxidizing conditions was investigated using simulated automotive exhaust gas from lean-burn combustion. The conversion of hydrocarbons and NOx was measured in cycled feedstream and steady feedstream under oxidizing conditions. The activities of the catalysts were improved in the cycled feedstream between oxidizing and reducing atmospheres under

H. Shinjoh; N. Takahashi; K. Yokota; M. Sugiura

1998-01-01

157

Development of a tunable diode laser sensor for measurements of gas turbine exhaust temperature  

Microsoft Academic Search

A tunable diode laser (TDL) temperature sensor is designed, constructed, tested, and demonstrated in the exhaust of an industrial gas turbine. Temperature is determined from the ratio of the measured absorbance of two water vapor overtone transitions in the near infrared where telecommunication diode lasers are available. Design rules are developed to select the optimal pair of transitions for direct

X. Liu; J. B. Jeffries; R. K. Hanson; K. M. Hinckley; M. A. Woodmansee

2006-01-01

158

Diesel engine exhaust gas recirculation––a review on advanced and novel concepts  

Microsoft Academic Search

Exhaust gas recirculation (EGR) is effective to reduce nitrogen oxides (NOx) from Diesel engines because it lowers the flame temperature and the oxygen concentration of the working fluid in the combustion chamber. However, as NOx reduces, particulate matter (PM) increases, resulting from the lowered oxygen concentration. When EGR further increases, the engine operation reaches zones with higher instabilities, increased carbonaceous

Ming Zheng; Graham T. Reader; J. Gary Hawley

2004-01-01

159

Chemical heat-pump system working at exhaust temperatures of high-temperature-gas-cooled reactor  

Microsoft Academic Search

A chemical heat-pump system using two hydrogen-absorbing alloys is proposed to utilize heat exhausted from a high-temperature source such as high-temperature-gas-cooled reactor, HTGR, which is designed to produce H2 more efficiently. The overall system proposed here consists of HTGR, He gas turbines, chemical heat pumps and reaction vessels corresponding to the three-step decomposition reactions comprising the I–S process. A fundamental

Satoshi Fukada; Yuki Edao; Masabumi Terashita

2009-01-01

160

Method and apparatus to selectively reduce NO.sub.x in an exhaust gas feedstream  

DOEpatents

A method and apparatus are described to selectively reduce NO.sub.x emissions of an internal combustion engine. An exhaust aftertreatment system includes an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NO.sub.x concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may include engine fuel.

Schmieg, Steven J. (Troy, MI); Blint, Richard J. (Shelby Township, MI); Den, Ling (Sterling Heights, MI); Viola, Michael B. (Macomb Township, MI); Lee, Jong-Hwan (Rochester Hills, MI)

2011-08-30

161

Turbine exhaust diffuser with a gas jet producing a coanda effect flow control  

DOEpatents

An exhaust diffuser system and method for a turbine engine includes an inner boundary and an outer boundary with a flow path defined therebetween. The inner boundary is defined at least in part by a hub structure that has an upstream end and a downstream end. The outer boundary may include a region in which the outer boundary extends radially inward toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. The hub structure includes at least one jet exit located on the hub structure adjacent to the upstream end of the tail cone. The jet exit discharges a flow of gas substantially tangential to an outer surface of the tail cone to produce a Coanda effect and direct a portion of the exhaust flow in the diffuser toward the inner boundary.

Orosa, John; Montgomery, Matthew

2014-02-11

162

Pollutant constituents of exhaust emitted from light-duty diesel vehicles  

NASA Astrophysics Data System (ADS)

Light-duty diesel exhaust particulate matter and its constituents, including elemental carbon, organic carbon, water-soluble ionic species, elements, and polyaromatic hydrocarbons (PAHs), were measured by a dynamometer study and following the driving pattern of federal test procedure-75 (FTP-75). Fuel consumption of these light-duty diesel vehicles (LDDV) was in the range of 0.106-0.132 l km -1, and the average emission factors of NMHC (non-methane hydrocarbon), CO and NO x for light-duty vehicles were 0.158 (92% of total hydrocarbon), 1.395, and 1.735 g km -1, respectively. The particulate emission factor of LDDVs was 0.172 g km -1, and PM 2.5 contributed to 88% of particulate mass. Al, S, Ca, and Fe emission factors were about 0.83-1.24 mg km -1 for PM 2.5, and the particulate mass fractions of these elements ranged from 66 to 90% in PM 2.5. Nitrate, sulfate, ammonium and nitrite were the major ionic species in diesel PM, and their emission factor ranged from 0.22 to 0.82 mg km -1 for PM 2.5. The emission factor of total PAHs was 3.62 mg km -1 in this study, with about 40% in the gas phase and 60% in the particulate phase. Acenaphylene, naphthalene, fluoranthene, pyrene, and anthracene were the dominant PAHs, and their emission factors were more than 0.19 mg km -1. The content of nitro-PAHs was low, with most less than 0.040 mg km -1.

Chiang, Hung-Lung; Lai, Yen-Ming; Chang, Sheng-You

2012-02-01

163

Interaction between struts and swirl flow in gas turbine exhaust diffusers  

NASA Astrophysics Data System (ADS)

The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modern gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions. Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter (LDV). Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle settings. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.

Pietrasch, Roman Z.; Seume, Joerg R.

2005-12-01

164

Effect of Exhaust Gas Recirculation (EGR) on performance, emissions, deposits and durability of a constant speed compression ignition engine  

Microsoft Academic Search

To meet stringent vehicular exhaust emission norms worldwide, several exhaust pre-treatment and post-treatment techniques have been employed in modern engines. Exhaust Gas Recirculation (EGR) is a pre-treatment technique, which is being used widely to reduce and control the oxides of nitrogen (NOx) emission from diesel engines. EGR controls the NOx because it lowers oxygen concentration and flame temperature of the

Deepak Agarwal; Shrawan Kumar Singh; Avinash Kumar Agarwal

2011-01-01

165

Thermoelectric Power Generation System for Future Hybrid Vehicles Using Hot Exhaust Gas  

NASA Astrophysics Data System (ADS)

The present experimental and computational study investigates a new exhaust gas waste heat recovery system for hybrid vehicles, using a thermoelectric module (TEM) and heat pipes to produce electric power. It proposes a new thermoelectric generation (TEG) system, working with heat pipes to produce electricity from a limited hot surface area. The current TEG system is directly connected to the exhaust pipe, and the amount of electricity generated by the TEMs is directly proportional to their heated area. Current exhaust pipes fail to offer a sufficiently large hot surface area for the high-efficiency waste heat recovery required. To overcome this, a new TEG system has been designed to have an enlarged hot surface area by the addition of ten heat pipes, which act as highly efficient heat transfer devices and can transmit the heat to many TEMs. As designed, this new waste heat recovery system produces a maximum 350 W when the hot exhaust gas heats the evaporator surface of the heat pipe to 170°C; this promises great possibilities for application of this technology in future energy-efficient hybrid vehicles.

Kim, Sun-Kook; Won, Byeong-Cheol; Rhi, Seok-Ho; Kim, Shi-Ho; Yoo, Jeong-Ho; Jang, Ju-Chan

2011-05-01

166

RE-ENTRAINMENT AND DISPERSION OF EXHAUSTS FROM INDOOR RADON REDUCTION SYSTEMS: ANALYSIS OF TRACER GAS DATA  

EPA Science Inventory

The paper discusses two tracer gas studies, to quantify the extent to which exhaust gases from indoor radon reduction systems are re-entrained into pitched-roof houses (exposing persons indoors), and the manner in which the exhausts disperse outdoors (exposing persons outside the...

167

Development of a tunable diode laser sensor for measurements of gas turbine exhaust temperature  

Microsoft Academic Search

A tunable diode laser (TDL) temperature sensor is designed, constructed, tested, and demonstrated in the exhaust of an industrial\\u000a gas turbine. Temperature is determined from the ratio of the measured absorbance of two water vapor overtone transitions in\\u000a the near infrared where telecommunication diode lasers are available. Design rules are developed to select the optimal pair\\u000a of transitions for direct

X. Liu; J. B. Jeffries; R. K. Hanson; K. M. Hinckley; M. A. Woodmansee

2006-01-01

168

A Gas Chromatograph/Mass Spectrometer System for UltraLow-Emission Combustor Exhaust Studies  

NASA Technical Reports Server (NTRS)

A gas chromatograph (GC)/mass spectrometer (MS) system that allows the speciation of unburnt hydrocarbons in the combustor exhaust has been developed at the NASA Lewis Research Center. Combustion gas samples are withdrawn through a water-cooled sampling probe which, when not in use, is protected from contamination by a high-pressure nitrogen purge. The sample line and its connecting lines, filters, and valves are all ultraclean and are heated to avoid condensation. The system has resolution to the parts-per-billion (ppb) level.

Brabbs, Theodore A.; Wey, Chowen Chou

1996-01-01

169

Integrated exhaust gas analysis system for aircraft turbine engine component testing  

NASA Technical Reports Server (NTRS)

An integrated exhaust gas analysis system was designed and installed in the hot-section facility at the Lewis Research Center. The system is designed to operate either manually or automatically and also to be operated from a remote station. The system measures oxygen, water vapor, total hydrocarbons, carbon monoxide, carbon dioxide, and oxides of nitrogen. Two microprocessors control the system and the analyzers, collect data and process them into engineering units, and present the data to the facility computers and the system operator. Within the design of this system there are innovative concepts and procedures that are of general interest and application to other gas analysis tasks.

Summers, R. L.; Anderson, R. C.

1985-01-01

170

Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer  

NASA Astrophysics Data System (ADS)

A new approach was developed to measure the total abundance of long chain alkanes (C12 and above) in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS). These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1), monocyclic aromatics, and an ion group with formula CnH2n-1 (m/z 97, 111, 125, 139). The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 ?g m-3 to 100 ?g m-3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.

Erickson, M. H.; Wallace, H. W.; Jobson, B. T.

2012-02-01

171

Effects of Exhaust Gas Recirculation on SI Engines at Wide Open Throttle  

NASA Astrophysics Data System (ADS)

Exhaust gas recirculation, a charge dilution technique, has proven to be an effective method of reducing NOx emissions and fuel consumption of spark ignition engines. Wide open throttle operation also increases overall engine efficiency by reducing the pumping losses caused by throttling. In this study, the emissions and fuel economy benefits of exhaust gas recirculation (EGR) at wide open throttle conditions were quantified using a 2.4L port-injected engine. Engine performance and emissions data were recorded as the percentage of EGR in the intake charge was increased from zero to just above thirty percent (the EGR limit). This EGR percentage, in-cylinder pressure measurements, and the temperatures and pressures of the intake and exhaust were all recorded to ensure stable operating conditions. These tests were performed with a stoichiometric air-fuel ratio at a constant speed of 2000 rpm at wide open throttle. The variation of brake specific fuel consumption and emissions (in particular NOx) with increasing EGR percentages was analyzed.

Bronson, Sydney; Puzinauskas, Paulius

2011-11-01

172

Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment  

PubMed Central

Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more sophisticated approaches based on interactions with electromagnetic waves are also reviewed. For that purpose, metallic stick-like antennas are inserted into the exhaust pipe. The catalyst properties are measured in a contactless manner, directly indicating the catalyst status. The radio frequency probes gauge the oxygen loading degree of three-way catalysts, the NOx-loading of lean NOx traps, and the soot loading of Diesel particulate filters. PMID:22163575

Moos, Ralf

2010-01-01

173

Environmental policy constraints for acidic exhaust gas scrubber discharges from ships.  

PubMed

Increasingly stringent environmental legislation on sulphur oxide emissions from the combustion of fossil fuels onboard ships (International Maritime Organization (IMO) Regulation 14) can be met by either refining the fuel to reduce sulphur content or by scrubbing the exhaust gases. Commonly used open loop marine scrubbers discharge warm acidic exhaust gas wash water into the sea, depressing its pH. The focus on this paper is on the physics and chemistry behind the disposal of acidic discharges in seawater. The IMO Marine Environment Protection Committee (MEPC 59/24/Add.1 Annex 9) requires the wash water to reach a pH greater than 6.5 at a distance of 4m from the point of discharge. We examine the engineering constraints, specifically size and number of ports, to identify the challenges of meeting regulatory compliance. PMID:25284442

Ülpre, H; Eames, I

2014-11-15

174

RESEARCH AREA -- FLUE GAS CLEANING (AIR POLLUTION TECHNOLOGY BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)  

EPA Science Inventory

The Air Pollution Technology Branch's (APPCD, NRMRL)flue gas cleaning program supports New Source Performance Standards regulations development and has fostered the development of technologies that today are considered industry standards. These include both dry and wet flue gas d...

175

Integrated capture of fossil fuel gas pollutants including CO.sub.2 with energy recovery  

DOEpatents

A method of reducing pollutants exhausted into the atmosphere from the combustion of fossil fuels. The disclosed process removes nitrogen from air for combustion, separates the solid combustion products from the gases and vapors and can capture the entire vapor/gas stream for sequestration leaving near-zero emissions. The invention produces up to three captured material streams. The first stream is contaminant-laden water containing SO.sub.x, residual NO.sub.x particulates and particulate-bound Hg and other trace contaminants. The second stream can be a low-volume flue gas stream containing N.sub.2 and O.sub.2 if CO2 purification is needed. The final product stream is a mixture comprising predominantly CO.sub.2 with smaller amounts of H.sub.2O, Ar, N.sub.2, O.sub.2, SO.sub.X, NO.sub.X, Hg, and other trace gases.

Ochs, Thomas L. (Albany, OR); Summers, Cathy A. (Albany, OR); Gerdemann, Steve (Albany, OR); Oryshchyn, Danylo B. (Philomath, OR); Turner, Paul (Independence, OR); Patrick, Brian R. (Chicago, IL)

2011-10-18

176

Air pollution & the brain: Subchronic diesel exhaust exposure causes neuroinflammation and elevates early markers of neurodegenerative disease  

PubMed Central

Background Increasing evidence links diverse forms of air pollution to neuroinflammation and neuropathology in both human and animal models, but the effects of long-term exposures are poorly understood. Objective We explored the central nervous system consequences of subchronic exposure to diesel exhaust (DE) and addressed the minimum levels necessary to elicit neuroinflammation and markers of early neuropathology. Methods Male Fischer 344 rats were exposed to DE (992, 311, 100, 35 and 0 ?g PM/m3) by inhalation over 6 months. Results DE exposure resulted in elevated levels of TNF? at high concentrations in all regions tested, with the exception of the cerebellum. The midbrain region was the most sensitive, where exposures as low as 100 ?g PM/m3 significantly increased brain TNF? levels. However, this sensitivity to DE was not conferred to all markers of neuroinflammation, as the midbrain showed no increase in IL-6 expression at any concentration tested, an increase in IL-1? at only high concentrations, and a decrease in MIP-1? expression, supporting that compensatory mechanisms may occur with subchronic exposure. A?42 levels were the highest in the frontal lobe of mice exposed to 992 ?g PM/m3 and tau [pS199] levels were elevated at the higher DE concentrations (992 and 311 ?g PM/m3) in both the temporal lobe and frontal lobe, indicating that proteins linked to preclinical Alzheimer's disease were affected. ? Synuclein levels were elevated in the midbrain in response to the 992 ?g PM/m3 exposure, supporting that air pollution may be associated with early Parkinson's disease-like pathology. Conclusions Together, the data support that the midbrain may be more sensitive to the neuroinflammatory effects of subchronic air pollution exposure. However, the DE-induced elevation of proteins associated with neurodegenerative diseases was limited to only the higher exposures, suggesting that air pollution-induced neuroinflammation may precede preclinical markers of neurodegenerative disease in the midbrain. PMID:21864400

2011-01-01

177

Multiple Exhaust Nozzle Effects on J-2X Gas Generator Outlet Impedance  

NASA Technical Reports Server (NTRS)

The current test setup of the J-2X gas generator system uses a multiple nozzle configuration to exhaust hot gases to drive the propellant supply turbines. Combustion stability assessment of this gas generator design requires knowledge of the impedance effects the multiple nozzle configuration creates on the combustion chamber acoustic modes. Parallel work between NASA and Sierra Engineering is presented, showing two methods used to calculate the effective end impedance resulting from multiple nozzle configurations. The NASA method is a simple estimate of the effective impedance using the long wavelength approximation. Sierra Engineering has developed a more robust numerical integration method implemented in ROCCID to accommodate for multiple nozzles. Analysis using both methods are compared to J-2X gas generator test data collected over the past year.

Kenny, R. Jeremy; Muss, Jeffrey; Hulka, James R.; Casiano, Matthew

2010-01-01

178

Variable-geometry turbocharger with asymmetric divided volute for engine exhaust gas pulse optimization  

DOEpatents

A turbine assembly for a variable-geometry turbocharger includes a turbine housing defining a divided volute having first and second scrolls, wherein the first scroll has a substantially smaller volume than the second scroll. The first scroll feeds exhaust gas to a first portion of a turbine wheel upstream of the throat of the wheel, while the second scroll feeds gas to a second portion of the wheel at least part of which is downstream of the throat. Flow from the second scroll is regulated by a sliding piston. The first scroll can be optimized for low-flow conditions such that the turbocharger can operate effectively like a small fixed-geometry turbocharger when the piston is closed. The turbine housing defines an inlet that is divided by a dividing wall into two portions respectively feeding gas to the two scrolls, a leading edge of the dividing wall being downstream of the inlet mouth.

Serres, Nicolas (Epinal, FR)

2010-11-09

179

High Speed H2O Concentration Measurements Using Absorption Spectroscopy to Monitor Exhaust Gas  

SciTech Connect

This paper demonstrates the potential for fast absorption spectroscopy measurements in diesel-engine exhaust to track H2O concentration transients. Wavelength-agile absorption spectroscopy is an optical technique that measures broadband absorption spectra between 10kHz and 100 MHz. From these measured spectra, gas temperature and absorber concentration can be determined. The Fourier-domain mode-locking (FDML) laser is becoming recognized as one of the most robust and reliable wavelength-agile sources available. H2O concentration measurements during combustion events at crank angle resolved speeds are beneficial for a wide variety of applications, such as product improvements for industry, control and reliability checks for experimental researchers, and measures of fit for numerical simulations. The difficulties associated with measuring diesel exhaust compared to in-cylinder measurements are discussed. A full description of the experimental configuration and data processing is explained. Measurements of engine exhaust H2O transients with 10- s temporal resolution are presented for a range of engine conditions.

Kranendonk, Laura [ORNL; Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL; Partridge Jr, William P [ORNL

2008-01-01

180

Evaluating tractor performance and exhaust gas emissions using biodiesel from cotton seed oil  

NASA Astrophysics Data System (ADS)

Alternative fuels for diesel engines, such as biodiesel, have attracted much attention recently due to increasing fuel prices and the imperative to reduce emissions. The exhaust gas emissions from tractors and other agricultural machinery make a significant contribution to these emissions. The use of biodiesel in internal combustion engines (ICE) has been reported to give comparable performance to conventional diesel (CD), but with generally lower emissions. There is however, contradictory evidence of NO emissions being both higher and lower from the use of biodiesel. In this work, agriculture tractor engine performance and its emission using both CD and biodiesel from cotton seed oil (CSO-B20) mixed at a 20% blend ration has been evaluated and compared. The PTO test results showed comparable exhaust emissions between CD and CSO-B20. However, the use of CSO-B20 led to reductions in the thermal efficiency and exhaust temperature and an increase in the brake specific fuel consumption (BSFC), when compared to CD.

Al-lwayzy, Saddam H.; Yusaf, Talal; Jensen, Troy

2012-09-01

181

Comments on the low frequency radiation impedance of a duct exhausting a hot gas.  

PubMed

The influence of convection and temperature on the radiation impedance of an open duct termination exhausting a hot gas is commonly described by a complex theory. A simplified analytical expression is proposed for low frequencies. Both models assume a free jet with uniform velocity bounded by infinitely thin shear layers. The convective velocity that should be assumed when applying these models to a non-uniform outflow is uncertain. A simplified version of the so-called Vortex Sound Theory demonstrates that the convective velocity one should assume is lower than the jet centerline velocity. PMID:25096151

Hirschberg, Avraham; Hoeijmakers, Maarten

2014-08-01

182

In utero and early life exposure to diesel exhaust air pollution increases adult susceptibility to heart failure in mice  

PubMed Central

Background Fine particulate air pollution (PM2.5) is a global health concern, as exposure to PM2.5 has consistently been found to be associated with increased cardiovascular morbidity and mortality. Although adult exposure to traffic related PM2.5, which is largely derived from diesel exhaust (DE), has been associated with increased cardiac hypertrophy, there are limited investigations into the potential effect of in utero and early life exposure on adult susceptibility to heart disease. In this study, we investigate the effect of in utero and early life exposure to DE on adult susceptibility to heart failure. Methods Female C57BL/6 J mice were exposed to either filtered air (FA) or DE for 3 weeks (?300 ?g/m3 PM2.5 for 6 hours/day, 5 days/week) and then introduced to male breeders for timed matings. Female mice were exposed to either FA or DE throughout pregnancy and until offspring were 3 weeks of age. Offspring were then transferred to either FA or DE for an additional 8 weeks of exposure. At 12 weeks of age, male offspring underwent a baseline echocardiographic assessment, followed by a sham or transverse aortic constriction (TAC) surgery to induce pressure overload. Following sacrifice three weeks post surgery, ventricles were processed for histology to assess myocardial fibrosis and individual cardiomyocyte hypertrophy. mRNA from lung tissue was isolated to measure expression of inflammatory cytokines IL6 and TNF?. Results We observed that mice exposed to DE during in utero and early life development have significantly increased susceptibility to cardiac hypertrophy, systolic failure, myocardial fibrosis, and pulmonary congestion following TAC surgery compared to FA control, or adult DE exposed mice. In utero and early life DE exposure also strongly modified the inflammatory cytokine response in the adult lung. Conclusions We conclude that exposure to diesel exhaust air pollution during in utero and early life development in mice increases adult susceptibility to heart failure. The results of this study may imply that the effects of air pollution on cardiovascular disease in human populations may be strongly mediated through a ‘fetal origins’ of adult disease pathway. Further investigations on this potential pathway of disease are warranted. PMID:24279743

2013-01-01

183

Detection of ethene and other hydrocarbons in gas turbine engine exhaust using non-intrusive FTIR spectroscopy  

Microsoft Academic Search

As part of the EU funded project AEROJET2, a number of gas turbine engine tests were performed in different facilities around Europe. At Farnborough, UK a Spey engine was used to test a suite of prototype optically based instrumentation designed to measure exhaust gas emissions without using extractive probe systems. In addition to the AEROJET 2 prototype instrumentation, a Bruker

Giovanni M. Arrigone; Michael A. Welch; Moira Hilton; Michael N. Miller; Christopher W. Wilson

2003-01-01

184

Use of exhaust gas recirculation as a control approach for thermoacoustic instabilities  

SciTech Connect

Investigation into exhaust gas recirculation (EGR) as a method for reducing costs of postcombustion carbon capture in gas turbine systems reveals that EGR offers potential applications as a control strategy for thermoacoustic instabilities. Introduction of EGR allows semi-independent variation of the operating parameter of flame temperature and characteristic flame length scales, known to play a primary role in the phase of the thermoacoustic coupling mechanism. Measurements were made showing the ability of EGR to reduce the amplitude of thermoacoustic oscillations over a range of operating conditions in a laboratory scale, swirled dump combustor, without affecting the flame temperature. Theoretical analysis was also performed to investigate the limitations on the ability of this approach to influence dynamics.

Ranalli, J.; Ferguson, D.

2011-10-09

185

Air pollution from aircraft. [jet exhaust - aircraft fuels/combustion efficiency  

NASA Technical Reports Server (NTRS)

A model which predicts nitric oxide and carbon monoxide emissions from a swirl can modular combustor is discussed. A detailed analysis of the turbulent fuel-air mixing process in the swirl can module wake region is reviewed. Hot wire anemometry was employed, and gas sampling analysis of fuel combustion emissions were performed.

Heywood, J. B.; Chigier, N. A.

1975-01-01

186

Effect of the Sequence of the Thermoelectric Generator and the Three-Way Catalytic Converter on Exhaust Gas Conversion Efficiency  

NASA Astrophysics Data System (ADS)

The potential for thermoelectric exhaust heat recovery in vehicles has increased with recent improvements in the efficiency of thermoelectric generators (TEGs). The problem with using thermoelectric generators for vehicle applications is whether the device is compatible with the original vehicle exhaust system, which determines the quality of the exhaust gas treatment and the realization of energy conservation and emission reduction. Based on ANSYS CFX simulation analysis of the impact of two positional relationships between the TEG and three-way catalytic converter in the exhaust system on the working efficiency of both elements, it is concluded that the layout with the front three-way catalytic converter has an advantage over the other layout mode under current conditions. New ideas for an improvement program are proposed to provide the basis for further research.

Su, Chuqi; Tong, Naiqiang; Xu, Yuman; Chen, Shan; Liu, Xun

2013-07-01

187

A study on exhaust gas emissions from ships in Turkish Straits  

NASA Astrophysics Data System (ADS)

The Turkish Straits, i.e. Istanbul (Bosphorus) and Canakkale (Dardanellen), which connect Black Sea and Aegean Sea, have a continuously increasing maritime traffic. Especially, the maritime traffic on Bosphorus (Istanbul Strait) that connects the continents of Europe and Asia is too complex due to geographical conditions. The maritime traffic in the Turkish Straits includes the ships, which are in use in domestic transport, the transit passing ships with various aims and fishing, sport or strolling ships. In this paper, fuel consumption and exhaust gas emissions NO x, CO, CO 2, VOC, PM exhausted from ships such as transit vessels, which are passing both Bosphorus and Dardanellen, and passenger ships used in domestic transport on the Bosphorus are calculated. In order to do this the general characteristics, the main engine systems, the fuel types, cruising times and speeds of all vessels are taken into consideration. The calculated NO x emissions on the Bosphorus are 2720 t from domestic passenger ships and 4357 t from transit ships. In this case it is clear that the transit ships cause more than half of the total amount of emissions from ships on the Bosphorus. The amount of nitrogen oxide emissions from domestic passenger ships used for public transport in Istanbul Strait is equal to approx. 4% of nitrogen oxide emissions from motor vehicles in Istanbul. Finally, the future emissions from ships in Turkish Straits are discussed.

Kesgin, Ugur; Vardar, Nurten

188

Design of a diesel exhaust-gas purification system for inert-gas drilling  

SciTech Connect

To combat the serious oxygen corrosion of drill pipe when a low density drilling fluid (air or mist) is used in geothermal drilling, a system has been designed that produces an inert gas (essentially nitrogen) to be substituted for air. The system fits on three flatbed trailers, is roadable and produces 2000 scfm of gas. The projected cost for gas is slightly less than $2.00 per thousand standard cubic feet.

Caskey, B.C.

1982-01-01

189

DESIGN CRITERIA FOR ROCKET EXHAUST SCRUBBERS  

EPA Science Inventory

The report gives results of an engineering study and design of methods for scrubbing the exhaust of static-tested solid rockets. Pollutants of major concern were hydrogen chloride and hydrogen fluoride gases. The best process for removing these gases was found to be a gas-atomize...

190

Vascular and Cardiac Impairments in Rats Inhaling Ozone and Diesel Exhaust Particles  

EPA Science Inventory

Background -Mechanisms of cardiovascular injuries from exposure to gas and particulate air pollutants are unknown. Objective -We hypothesized that episodic exposure of rats to ozone or diesel exhaust particles (DEP) will cause differential cardiovascular impairments, which will b...

191

Pollutant swapping: greenhouse gas emissions from wetland systems constructed to mitigate agricultural pollution  

NASA Astrophysics Data System (ADS)

Diffuse (non-point) water pollution from agricultural land continues to challenge water quality management, requiring the adoption of new land management practices. The use of constructed agricultural wetlands is one such practice, designed to trap multiple pollutants mobilised by rainfall prior to them reaching receiving water. Through capturing and storing pollutants in bottom sediments, it could be hypothesised that the abundance of nutrients stored in the anoxic conditions commonly found in these zones may lead to pollutant swapping. Under these circumstances, trapped material may undergo biogeochemical cycling to change chemical or physical form and thereby become more problematic or mobile within the environment. Thus, constructed agricultural wetlands designed to mitigate against one form of pollution may in fact offset the created benefits by 'swapping' this pollution into other forms and pathways, such as through release to the atmosphere. Pollutant swapping to the atmosphere has been noted in analogous wetland systems designed to treat municipal and industrial wastewaters, with significant fluxes of CO2, CH4 and N2O being recorded in some cases. However the small size, low level of engineering and variable nutrient/sediment inputs which are features of constructed agricultural wetlands, means that this knowledge is not directly transferable. Therefore, more information is required when assessing whether a wetland's potential to act as hotspot for pollution swapping outweighs its potential to act as a mitigation tool for surface water pollution. Here we present results from an on-going monitoring study at a trial agricultural wetland located in small a mixed-use catchment in Cumbria, UK. Estimates were made of CH4, CO2 and N2O flux from the wetland surface using adapted floating static chambers, which were then directly compared with fluxes from an undisturbed riparian zone. Results indicate that while greenhouse gas flux from the wetland may be significant, the impacts of this may be greatly diminished when considering wetland size in relation to catchment area. As such, this increased understanding will be valuable when considering the implications of rural land use management for water quality improvement. This knowledge could also be applied to further enhancing our knowledge of gas regional/global gas emissions from freshwater systems, which at the moment are poorly constrained.

Freer, Adam; Quinton, John; Surridge, Ben; McNamara, Niall

2014-05-01

192

Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor  

PubMed Central

Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well. PMID:22423212

Biskupski, Diana; Geupel, Andrea; Wiesner, Kerstin; Fleischer, Maximilian; Moos, Ralf

2009-01-01

193

Finding new reserves of oil and gas As the world's reserves of oil and gas become exhausted, we urgently need to find new  

E-print Network

Finding new reserves of oil and gas As the world's reserves of oil and gas become exhausted, we urgently need to find new fields to answer our energy needs. Oil companies are keen to use novel techniques) techniques represent arguably the most significant technological advance in the field of oil exploration

Anderson, Jim

194

First online measurements of sulfuric acid gas in modern heavy-duty diesel engine exhaust: implications for nanoparticle formation.  

PubMed

To mitigate the diesel particle pollution problem, diesel vehicles are fitted with modern exhaust after-treatment systems (ATS), which efficiently remove engine-generated primary particles (soot and ash) and gaseous hydrocarbons. Unfortunately, ATS can promote formation of low-vapor-pressure gases, which may undergo nucleation and condensation leading to formation of nucleation particles (NUP). The chemical nature and formation mechanism of these particles are only poorly explored. Using a novel mass spectrometric method, online measurements of low-vapor-pressure gases were performed for exhaust of a modern heavy-duty diesel engine operated with modern ATS and combusting low and ultralow sulfur fuels and also biofuel. It was observed that the gaseous sulfuric acid (GSA) concentration varied strongly, although engine operation was stable. However, the exhaust GSA was observed to be affected by fuel sulfur level, exhaust after-treatment, and driving conditions. Significant GSA concentrations were measured also when biofuel was used, indicating that GSA can be originated also from lubricant oil sulfur. Furthermore, accompanying NUP measurements and NUP model simulations were performed. We found that the exhaust GSA promotes NUP formation, but also organic (acidic) precursor gases can have a role. The model results indicate that that the measured GSA concentration alone is not high enough to grow the particles to the detected sizes. PMID:23035617

Arnold, F; Pirjola, L; Rönkkö, T; Reichl, U; Schlager, H; Lähde, T; Heikkilä, J; Keskinen, J

2012-10-16

195

Dynamic Control of Engine NOx Emissions: Characterization and Improvement of the Transient Response of an Exhaust Gas Recirculation System  

Microsoft Academic Search

An effective method for reducing NOx emissions from automotive engines is to use exhaust gas recirculation (EGR) to dilute the inducted air-fuel charge. Previous work has shown that degraded propagation delay and rise time characteristics of an EGR system can result in increases in NOx emissions for engine operation over dynamic rpm\\/torque versus time trajectories as exemplified by the Federal

M. J. Throop; D. R. Hamburg

1985-01-01

196

Calculations of economy of 18-cylinder radial aircraft engine with exhaust-gas turbine geared to the crankshaft  

NASA Technical Reports Server (NTRS)

Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work.

Hannum, Richard W; Zimmerman, Richard H

1945-01-01

197

RE-ENTRAINMENT AND DISPERSION OF EXHAUSTS FROM INDOOR RADON REDUCTION SYSTEMS: ANALYSIS OF TRACER GAS DATA  

EPA Science Inventory

Tracer gas studies were conducted around four model houses in a wind tunnel, and around one house in the field, to quantify re-entrainment and dispersion of exhaust gases released from residential indoor radon reduction systems. Re-entrainment tests in the field suggest that acti...

198

NO x emission and performance data for a hydrogen fueled internal combustion engine at 1500 rpm using exhaust gas recirculation  

Microsoft Academic Search

This paper describes six experiments conducted on a 2-liter, 4-cylinder Ford ZETEC internal combustion engine developed to operate on hydrogen fuel. The experiments were conducted to ascertain the effect exhaust gas recirculation (EGR) and a standard 3-way catalytic converter had on NOx emissions and engine performance. All the experiments were conducted at a constant engine speed of 1500rpm and each

James W Heffel

2003-01-01

199

NO x emission reduction in a hydrogen fueled internal combustion engine at 3000 rpm using exhaust gas recirculation  

Microsoft Academic Search

This paper describes five experiments conducted on a 2-l, 4-cylinder Ford ZETEC internal combustion engine (ICE) developed to operate on hydrogen fuel. The experiments were conducted to ascertain the effect exhaust gas recirculation (EGR) and a standard 3-way catalytic converter had on NOx emissions and engine performance. All the experiments were conducted at a constant engine speed of 3000 rpm

James W Heffel

2003-01-01

200

Sync-ring assembly for a gas turbine engine exhaust nozzle  

SciTech Connect

A sync-ring assembly is described for selectively positioning divergent flap of a gas turbine engine exhaust nozzle relative to the exhaust nozzle's case, the nozzle having a centerline defined there through, the assembly comprising: a sync-ring pivotably connected to the divergent flaps by a plurality of positioning strut assemblies, the sync-ring having a first surface and a second surface radially outward of the first surface relative to the centerline, the second surface is semi-spherical, a plurality of shaft bores equally spaced about the circumference of the sync-ring, each shaft bore extending through the sync-ring between the first surface and the second surface, a liner having a cylindrical surface, the liner made of a wear resistant composite material and received within and supported by the nozzle case, the cylindrical surface slidably contacting the semi-spherical second surface, a plurality of shaft pins, each shaft pin extending through one of the shaft bores and protruding from the first surface, and each shaft pin pivotably connected to actuator means mounted to the nozzle case for selectively positioning the sync-ring relative to the nozzle case, and a plurality of supports mounted to the nozzle case, each support having a guide track therein; and, a plurality of roller bearings, each roller bearing rotatably mounted to one of the shaft pins, each bearing extending into one of the guide tracks; wherein the sync-ring is selectively rotatable between a first position in which all of the shaft pins are perpendicular to the cylindrical surface radially outward therefrom relative to the centerline, and a second position in which at least one of the shaft pins is at an angle of at least 5 to the cylindrical surface radially outward therefrom relative to the centerline, and the sync-ring is selectively positioned along a portion of the cylindrical surface.

Barcza, W.K.

1993-08-31

201

Dynamic instabilities in spark-ignited combustion engines with high exhaust gas recirculation  

SciTech Connect

We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). High EGR is important for increasing fuel efficiency and implementing advanced low-emission combustion modes such as homogenous charge compression ignition (HCCI). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR. We also explain why it might be helpful to deliberately stratify the fuel in the pre-spark gas mixture. It might be possible to extend the simple approach used in this model to other chemical reaction systems with spatial inhomogeneity.

Daw, C Stuart [ORNL] [ORNL; FINNEY, Charles E A [ORNL] [ORNL

2011-01-01

202

Vehicle exhaust gas clearance by low temperature plasma-driven nano-titanium dioxide film prepared by radiofrequency magnetron sputtering.  

PubMed

A novel plasma-driven catalysis (PDC) reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD) reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2) film prepared by radiofrequency (RF) magnetron sputtering was coated on the outer wall of the middle quartz tube, separating the catalyst from the high voltage electrode. The spiral electrodes were designed to avoid overheating of microdischarges inside the PDC reactor. Continuous operation tests indicated that stable performance without deterioration of catalytic activity could last for more than 25 h. To verify the effectiveness of the PDC reactor, a non-thermal plasma(NTP) reactor was employed, which has the same structure as the PDC reactor but without the catalyst. The real vehicle exhaust gas was introduced into the PDC reactor and NTP reactor, respectively. After the treatment, compared with the result from NTP, the concentration of HC in the vehicle exhaust gas treated by PDC reactor reduced far more obviously while that of NO decreased only a little. Moreover, this result was explained through optical emission spectrum. The O emission lines can be observed between 870 nm and 960 nm for wavelength in PDC reactor. Together with previous studies, it could be hypothesized that O derived from catalytically O3 destruction by catalyst might make a significant contribution to the much higher HC removal efficiency by PDC reactor. A series of complex chemical reactions caused by the multi-components mixture in real vehicle exhaust reduced NO removal efficiency. A controllable system with a real-time feedback module for the PDC reactor was proposed to further improve the ability of removing real vehicle exhaust gas. PMID:23560062

Yu, Shuang; Liang, Yongdong; Sun, Shujun; Zhang, Kai; Zhang, Jue; Fang, Jing

2013-01-01

203

Vehicle Exhaust Gas Clearance by Low Temperature Plasma-Driven Nano-Titanium Dioxide Film Prepared by Radiofrequency Magnetron Sputtering  

PubMed Central

A novel plasma-driven catalysis (PDC) reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD) reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2) film prepared by radiofrequency (RF) magnetron sputtering was coated on the outer wall of the middle quartz tube, separating the catalyst from the high voltage electrode. The spiral electrodes were designed to avoid overheating of microdischarges inside the PDC reactor. Continuous operation tests indicated that stable performance without deterioration of catalytic activity could last for more than 25 h. To verify the effectiveness of the PDC reactor, a non-thermal plasma(NTP) reactor was employed, which has the same structure as the PDC reactor but without the catalyst. The real vehicle exhaust gas was introduced into the PDC reactor and NTP reactor, respectively. After the treatment, compared with the result from NTP, the concentration of HC in the vehicle exhaust gas treated by PDC reactor reduced far more obviously while that of NO decreased only a little. Moreover, this result was explained through optical emission spectrum. The O emission lines can be observed between 870 nm and 960 nm for wavelength in PDC reactor. Together with previous studies, it could be hypothesized that O derived from catalytically O3 destruction by catalyst might make a significant contribution to the much higher HC removal efficiency by PDC reactor. A series of complex chemical reactions caused by the multi-components mixture in real vehicle exhaust reduced NO removal efficiency. A controllable system with a real-time feedback module for the PDC reactor was proposed to further improve the ability of removing real vehicle exhaust gas. PMID:23560062

Yu, Shuang; Liang, Yongdong; Sun, Shujun; Zhang, Kai; Zhang, Jue; Fang, Jing

2013-01-01

204

Lightweight Exhaust Manifold and Exhaust Pipe Ducting for Internal Combustion Engines  

NASA Technical Reports Server (NTRS)

An improved exhaust system for an internal combustion gasoline-and/or diesel-fueled engine includes an engine exhaust manifold which has been fabricated from carbon- carbon composite materials in operative association with an exhaust pipe ducting which has been fabricated from carbon-carbon composite materials. When compared to conventional steel. cast iron. or ceramic-lined iron paris. the use of carbon-carbon composite exhaust-gas manifolds and exhaust pipe ducting reduces the overall weight of the engine. which allows for improved acceleration and fuel efficiency: permits operation at higher temperatures without a loss of strength: reduces the "through-the wall" heat loss, which increases engine cycle and turbocharger efficiency and ensures faster "light-off" of catalytic converters: and, with an optional thermal reactor, reduces emission of major pollutants, i.e. hydrocarbons and carbon monoxide.

Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

1999-01-01

205

Fuel-Specific Effect of Exhaust Gas Residuals on HCCI Combustion: A Modeling Study  

SciTech Connect

A modeling study was performed to investigate fuel-specific effects of exhaust gas recirculation (EGR) components on homogeneous charge compression ignition (HCCI) combustion at conditions relevant to the negative valve overlap (NVO) strategy using CHEMKIN-PRO. Four single-component fuels with well-established kinetic models were chosen: n-heptane, iso-octane, ethanol, and toluene. These fuels were chosen because they span a wide range of fuel chemistries, and produce a wide compositions range of complete stoichiometric products (CSP). The simulated engine conditions combined a typical spark ignition engine compression ratio (11.34) and high intake charge temperatures (500-550 K) that are relevant to NVO HCCI. It was found that over the conditions investigated, all the fuels had overlapping start of combustion (SOC) phasing, despite the wide range in octane number (RON = 0 to 120). The effect of the EGR components CO2 and H2O was to suppress the compression temperature because of their higher heat capacities, which retarded SOC. For a concentration of O2 higher than the stoichiometric amount, or excess O2, there was an effect of advancing SOC for n-heptane, iso-octane, and toluene, but SOC for ethanol was not advanced. Low temperature heat release (LTHR) for n-heptane was also found to be highly dependent on excess O2, and mild endothermic reaction was observed for cases when excess O2 was not present.

Szybist, James P [ORNL

2008-01-01

206

Measurements of gas phase acids in diesel exhaust: a relevant source of HNCO?  

PubMed

Gas-phase acids in light duty diesel (LDD) vehicle exhaust were measured using chemical ionization mass spectrometry (CIMS). Fuel based emission factors (EF) and NOx ratios for these species were determined under differing steady state engine operating conditions. The derived HONO and HNO3 EFs agree well with literature values, with HONO being the single most important acidic emission. Of particular importance is the quantification of the EF for the toxic species, isocyanic acid (HNCO). The emission factors for HNCO ranged from 0.69 to 3.96 mg kgfuel(-1), and were significantly higher than previous biomass burning emission estimates. Further ambient urban measurements of HNCO demonstrated a clear relationship with the known traffic markers of benzene and toluene, demonstrating for the first time that urban commuter traffic is a source of HNCO. Estimates based upon the HNCO-benzene relationship indicate that upward of 23 tonnes of HNCO are released annually from commuter traffic in the Greater Toronto Area, far exceeding the amount possible from LDD alone. Nationally, 250 to 770 tonnes of HNCO may be emitted annually from on-road vehicles, likely representing the dominant source of exposure in urban areas, and with emissions comparable to that of biomass burning. PMID:23781923

Wentzell, Jeremy J B; Liggio, John; Li, Shao-Meng; Vlasenko, A; Staebler, Ralf; Lu, Gang; Poitras, Marie-Josée; Chan, Tak; Brook, Jeffrey R

2013-07-16

207

40 CFR 86.110-90 - Exhaust gas sampling system; diesel vehicles.  

Code of Federal Regulations, 2012 CFR

...complete mixing of the exhaust and dilution air between the mixing orifice and each of the two sample probes (i.e., the particulate...complete mixing of the exhaust and dilution air between the mixing orifice and the particulate sample probe. It is recommended that...

2012-07-01

208

40 CFR 86.110-90 - Exhaust gas sampling system; diesel vehicles.  

Code of Federal Regulations, 2013 CFR

...complete mixing of the exhaust and dilution air between the mixing orifice and each of the two sample probes (i.e., the particulate...complete mixing of the exhaust and dilution air between the mixing orifice and the particulate sample probe. It is recommended that...

2013-07-01

209

Apparatus for controlling the exhaust gas recirculation rate in an internal combustion engine  

Microsoft Academic Search

An apparatus is proposed for controlling the exhaust recirculation rate in an internal combustion engine, in particular an engine with auto-ignition, which includes preferably one mixture valve in the area of the discharge opening of the exhaust recirculation line and which is characterized in that the control is accomplished via the mixture valve position ahead of the inlet valves in

K. Muller; E. Linder; H. Maurer; F. Rieger

1984-01-01

210

Catalyst-coated expanded metal foil substrate for an exhaust gas reactor  

Microsoft Academic Search

A system for reducing NO\\/sub x\\/ gases found in the exhaust stream of the internal combustion engine is described which includes an internal combustion engine having associated therewith a means for supplying fuel and oxygen to the engine, a manifold system for directing or channeling the exhaust gases from the engine, and a NO\\/sub x\\/ reducing catalyst assembly communicating with

R. J. Fedor; C. S. Ogden

1978-01-01

211

Measuring Conventional and Alternative Exhaust Emissions from a Gas Turbine Engine  

E-print Network

by Sensors-Inc. was used for exhaust sampling of a PT6 turboprop engine on a test-stand located in an outdoor test cell. Exhaust emissions were collected for CO2, CO, NOx, and HC for three fuels (Jet A, HRJ, and FT) and analyzed for comparison in units...

Johnson, Jeremiah Andrew

2012-12-31

212

MODELING THE POLLUTION OF PRISTINE GAS IN THE EARLY UNIVERSE  

SciTech Connect

We conduct a comprehensive theoretical and numerical investigation of the pollution of pristine gas in turbulent flows, designed to provide useful new tools for modeling the evolution of the first generation of stars. The properties of such Population III (Pop III) stars are thought to be very different than those of later stellar generations, because cooling is dramatically different in gas with a metallicity below a critical value Z{sub c}, which lies between ?10{sup –6} and ?10{sup –3} Z{sub ?}. The critical value is much smaller than the typical overall average metallicity, , and therefore the mixing efficiency of the pristine gas in the interstellar medium plays a crucial role in determining the transition from Pop III to normal star formation. The small critical value, Z{sub c}, corresponds to the far left tail of the probability distribution function (PDF) of the metal abundance. Based on closure models for the PDF formulation of turbulent mixing, we derive evolution equations for the fraction of gas, P, lying below Z{sub c}, in statistically homogeneous compressible turbulence. Our simulation data show that the evolution of the pristine fraction P can be well approximated by a generalized 'self-convolution' model, which predicts that P-dot = - (n/?{sub con}) P (1-P{sup 1/n}), where n is a measure of the locality of the mixing or PDF convolution events and the convolution timescale ?{sub con} is determined by the rate at which turbulence stretches the pollutants. Carrying out a suite of numerical simulations with turbulent Mach numbers ranging from M = 0.9 to 6.2, we are able to provide accurate fits to n and ?{sub con} as a function of M, Z{sub c}/(Z), and the length scale, L{sub p}, at which pollutants are added to the flow. For pristine fractions above P = 0.9, mixing occurs only in the regions surrounding blobs of pollutants, such that n = 1. For smaller values of P, n is larger as the mixing process becomes more global. We show how these results can be used to construct one-zone models for the evolution of Pop III stars in a single high-redshift galaxy, as well as subgrid models for tracking the evolution of the first stars in large cosmological numerical simulations.

Pan, Liubin [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Scannapieco, Evan [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287-1494 (United States); Scalo, Jon, E-mail: lpan@cfa.harvard.edu, E-mail: evan.scannapieco@asu.edu, E-mail: parrot@astro.as.utexas.edu [Department of Astronomy, University of Texas, Austin, TX 78712 (United States)

2013-10-01

213

Modeling the Pollution of Pristine Gas in the Early Universe  

NASA Astrophysics Data System (ADS)

We conduct a comprehensive theoretical and numerical investigation of the pollution of pristine gas in turbulent flows, designed to provide useful new tools for modeling the evolution of the first generation of stars. The properties of such Population III (Pop III) stars are thought to be very different than those of later stellar generations, because cooling is dramatically different in gas with a metallicity below a critical value Z c, which lies between ~10-6 and ~10-3 Z ?. The critical value is much smaller than the typical overall average metallicity, , and therefore the mixing efficiency of the pristine gas in the interstellar medium plays a crucial role in determining the transition from Pop III to normal star formation. The small critical value, Z c, corresponds to the far left tail of the probability distribution function (PDF) of the metal abundance. Based on closure models for the PDF formulation of turbulent mixing, we derive evolution equations for the fraction of gas, P, lying below Z c, in statistically homogeneous compressible turbulence. Our simulation data show that the evolution of the pristine fraction P can be well approximated by a generalized "self-convolution" model, which predicts that \\dot{P} = - ({n}/{\\tau _con}) P (1-P^{1/n}), where n is a measure of the locality of the mixing or PDF convolution events and the convolution timescale ?con is determined by the rate at which turbulence stretches the pollutants. Carrying out a suite of numerical simulations with turbulent Mach numbers ranging from M = 0.9 to 6.2, we are able to provide accurate fits to n and ?con as a function of M, Z c/langZrang, and the length scale, L p, at which pollutants are added to the flow. For pristine fractions above P = 0.9, mixing occurs only in the regions surrounding blobs of pollutants, such that n = 1. For smaller values of P, n is larger as the mixing process becomes more global. We show how these results can be used to construct one-zone models for the evolution of Pop III stars in a single high-redshift galaxy, as well as subgrid models for tracking the evolution of the first stars in large cosmological numerical simulations.

Pan, Liubin; Scannapieco, Evan; Scalo, Jon

2013-10-01

214

Exhaust Gas Catalysts for Heavy-Duty Applications: Influence of the Pd Particle Size and Particle Size Distribution on the Combustion of Natural Gas and Biogas  

Microsoft Academic Search

In this study, an experimental investigation concerning exhaust gas catalysts for heavy-duty diesel engines fuelled by natural gas or biogas is presented. Miniature monoliths, 2.5 wt% Pd\\/Al2O3, have been prepared, characterised and tested. Various methods have been used in order to obtain different palladium particle sizes, including incipient wetness and microemulsion technique. Crystallite sizes between 2 and 40 nm were

E. Pocoroba; L. J. Pettersson; J. Agrell; M. Boutonnet; K. Jansson

2001-01-01

215

Apparatus and methods of reheating gas turbine cooling steam and high pressure steam turbine exhaust in a combined cycle power generating system  

DOEpatents

In a combined cycle system having a multi-pressure heat recovery steam generator, a gas turbine and steam turbine, steam for cooling gas turbine components is supplied from the intermediate pressure section of the heat recovery steam generator supplemented by a portion of the steam exhausting from the HP section of the steam turbine, steam from the gas turbine cooling cycle and the exhaust from the HP section of the steam turbine are combined for flow through a reheat section of the HRSG. The reheated steam is supplied to the IP section inlet of the steam turbine. Thus, where gas turbine cooling steam temperature is lower than optimum, a net improvement in performance is achieved by flowing the cooling steam exhausting from the gas turbine and the exhaust steam from the high pressure section of the steam turbine in series through the reheater of the HRSG for applying steam at optimum temperature to the IP section of the steam turbine.

Tomlinson, Leroy Omar (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)

2002-01-01

216

BLOOD GAS TENSIONS AND ACIDBASE REGULATION IN THE SALT-WATER CROCODILE, CROCODYLUS POROSUS, AT REST AND AFTER EXHAUSTIVE EXERCISE  

Microsoft Academic Search

SUMMARY 1. Salt-water crocodiles, Crocodylus porosus Schneider, were catheter- ized and Po2, Pco2, pH and lactate concentration ((lactate)) were measured in arterial blood during rest and after forced exhaustive activity at 30°C. 2. Gas exchange ratio (R), calculated from blood Po2 and Pco2, decreased from about 1-0 to 0-3 during resting voluntary breath-holding and indicated CO2 sequestration in the body

R. S. SEYMOUR; A. F. BENNETT; D. F. BRADFORD

217

Process for treating exhaust gas from internal combustion engine over catalyst comprising nickel, rhodium, and monolithic ceramic support  

Microsoft Academic Search

The process comprises passing the exhaust gas through a reduction zone containing a catalyst comprising a nickel component, a rhodium component, and a monolithic ceramic support and being maintained at a temperature of about 700 to about 1800°F. The catalyst may also contain a platinum component and\\/or a palladium component and the monolithic ceramic support may be coated with a

G. H. Meguerian; E. H. Hirschberg; F. W. Rakowsky

1977-01-01

218

Influence of an Optimized Thermoelectric Generator on the Back Pressure of the Subsequent Exhaust Gas System of a Vehicle  

NASA Astrophysics Data System (ADS)

Numerous research projects in automotive engineering focus on the industrialization of the thermoelectric generator (TEG). The development and the implementation of thermoelectric systems into the vehicle environment are commonly supported by virtual design activities. In this paper a customized simulation architecture is presented that includes almost all vehicle parts which are influenced by the TEG (overall system simulation) but is nevertheless capable of real-time use. Moreover, an optimized planar TEG with minimum nominal power output of about 580 W and pressure loss at nominal conditions of 10 mbar, synthesized using the overall system simulation, and the overall system simulation itself are used to answer a generally neglected question: What influence does the position of a TEG have on the back pressure of the subsequent exhaust gas system of the vehicle? It is found that the influence of the TEG on the muffler is low, but the catalytic converter is strongly influenced. It is shown that the TEG can reduce the back pressure of an exhaust gas system so much that its overall back pressure is less than the back pressure of a standard exhaust gas system.

Kühn, Roland; Koeppen, Olaf; Kitte, Jens

2014-06-01

219

Role of average speed in N?O exhaust emissions as greenhouse gas in a huge urban zone (MVMZ): would we need a cold sun?  

PubMed

Nowadays, the drastic pollution problems, some of them related with greenhouse gas emissions, have promoted important attempts to face and diminish the global warming effects on the Mexico Valley Metropolitan Zone (MVMZ) as well as on the huge urban zones around the world. To reduce the exhaust gas emissions, many efforts have been carried out to reformulate fuels and design new catalytic converters; however, it is well known that other variables such as socio-economic and transport structure factors also play an important role around this problem. The present study analyzes the roles played by several commonly-used three-way catalytic converters (TWC) and the average traffic speed in the emission of N(2)O as greenhouse gas. According to this study, by increasing the average traffic flow and avoiding constant decelerations (frequent stops) during common trips, remarkable environmental and economic benefits could be obtained due to the diminution of N(2)O and other contaminant emissions such as ammonia (NH(3)) and even CO(2) with the concomitant reduced fossil fuel consumption. The actions mentioned above could be highly viable to diminish, in general, the global warming effects and contamination problems. PMID:22245865

Castillo, S; Mac-Beath, I; Mejia, I; Camposeco, R; Bazan, G; Morán-Pineda, M; Carrera, R; Gómez, R

2012-05-15

220

40 CFR 86.1310-90 - Exhaust gas sampling and analytical system; diesel engines.  

Code of Federal Regulations, 2011 CFR

...measured in the diluted exhaust stream. The primary dilution air shall be sampled at the inlet to the primary dilution tunnel, if unfiltered, or downstream of any primary dilution air conditioning devices, if used. (2) [Reserved]...

2011-07-01

221

Exhaust Tuning of Large-Bore, Multicylinder, Two-Stroke, Natural Gas Engines  

Microsoft Academic Search

In this paper, computational modelling of the exhaust system of two types of large-bore, multicylinder, two-stroke engine is performed. The airflow performance of a four-cylinder V-bank Cooper GMV-4TF engine and a six-cylinder in-line Clark TLA engine is simulated. The simulation includes the computation of pressure wave propagation in the exhaust manifold. Using a modified method of the steepest ascent numerical

J Adair; D Olsen; A Kirkpatrick

2006-01-01

222

Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat  

NASA Astrophysics Data System (ADS)

A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.

Pak, Pyong Sik

223

Effects of Propane/Natural Gas Blended Fuels on Gas Turbine Pollutant Emissions  

SciTech Connect

U.S. natural gas composition is expected to be more variable in the future. Liquefied natural gas (LNG) imports to the U.S. are expected to grow significantly over the next 10-15 years. Unconventional gas supplies, like coal-bed methane, are also expected to grow. As a result of these anticipated changes, the composition of fuel sources may vary significantly from existing domestic natural gas supplies. To allow the greatest use of gas supplies, end-use equipment should be able to accommodate the widest possible gas composition. For this reason, the effect of gas composition on combustion behavior is of interest. This paper will examine the effects of fuel variability on pollutant emissions for premixed gas turbine conditions. The experimental data presented in this paper have been collected from a pressurized single injector combustion test rig at the National Energy Technology Laboratory (NETL). The tests are conducted at 7.5 atm with a 589K air preheat. A propane blending facility is used to vary the Wobbe Index of the site natural gas. The results indicate that propane addition of about five (vol.) percent does not lead to a significant change in the observed NOx emissions. These results vary from data reported in the literature for some engine applications and potential reasons for these differences are discussed.

D. Straub; D. Ferguson; K. Casleton; G. Richards

2006-03-01

224

Catalysts, systems and methods to reduce NOX in an exhaust gas stream  

DOEpatents

Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having an SCR catalyst comprising silver tungstate on an alumina support. The emissions treatment system may be used for the treatment of exhaust streams from diesel engines and lean burn gasoline engines. An emissions treatment system may further comprise an injection device operative to dispense a hydrocarbon reducing agent upstream of the catalyst.

Castellano, Christopher R. (Ringoes, NJ); Moini, Ahmad (Princeton, NJ); Koermer, Gerald S. (Basking Ridge, NJ); Furbeck, Howard (Hamilton, NJ)

2010-07-20

225

Efficiency of thermoelectric recuperators of the exhaust gas energy of internal combustion engines  

NASA Astrophysics Data System (ADS)

Results of computer simulation of thermoelectric generators (TEG) using the exhaust heat of internal combustion engines are presented. Sectionalized generator schematics whereby maximum efficiency is achieved for cases of real temperature dependences of the most suitable thermoelectric materials are considered. A model optimized for minimum cost is considered as well. Results of experimental research on generator that employs exhaust heat from heat and electricity cogeneration plant with a diesel engine are presented. Computer simulation is verified by the test results. The outlook for application of such heat recuperators in stationary plants is considered.

Anatychuk, L. I.; Kuz, R. V.; Rozver, Yu. Yu.

2012-06-01

226

40 CFR 86.1310-90 - Exhaust gas sampling and analytical system; diesel engines.  

Code of Federal Regulations, 2010 CFR

...FID, the hydrocarbon analysis can be made on the bag...methanol and formaldehyde analyses are performed on the...hydrocarbon plus methanol analyses are performed using...exhaust aftertreatment systems, or after a length...to provide additional information and coordinate the...

2010-07-01

227

The impact of using biodiesel/marine gas oil blends on exhaust emissions from a stationary diesel engine.  

PubMed

The purpose of this work was to investigate the impact of marine gas oil (MGO)/biodiesel blends on the exhaust emissions and fuel consumption in a single cylinder, stationary, diesel engine. Three different origins of biodiesel were used as the blending feedstock with the reference MGO, at proportions of 5 and 10% by volume. Methyl esters were examined according to the automotive FAME standard EN 14214. The baseline MGO and biodiesel blends were examined according to ISO 8217:2005 specifications for the DMA category. Independently of the biodiesel used, a decrease of PM, HC, CO and CO(2) emissions was observed. Emissions of NO(x) were also lower with respect to MGO. This reduction in NO(x) may be attributed to some physicochemical properties of the fuels applied, such as the higher cetane number and the lower volatility of methyl esters. Reductions in PM for biodiesel blends were lower in the exhaust than those of the reference fuel which was attributed to the oxygen content and the near absence of sulphur and aromatics compounds in biodiesel. However, a slight increase in fuel consumption was observed for the biodiesel blends that may be tolerated due to the exhaust emissions benefits. Brake thermal efficiency was also determined. Unregulated emissions were characterized by determining the soluble organic fraction content of the particulate matter. PMID:18988104

Karavalakis, G; Tzirakis, E; Mattheou, L; Stournas, S; Zannikos, F; Karonis, D

2008-12-01

228

Impact of oxidation catalysts on exhaust NO2/NOx ratio from lean-burn natural gas engines.  

PubMed

Oxides of nitrogen (NOx) emitted from internal combustion engines are composed primarily of nitric oxide (NO) and nitrogen dioxide (NO2). Exhaust from most combustion sources contains NOx composed primarily of NO. There are two important scenarios specific to lean-burn natural gas engines in which the NO2/NOx ratio can be significant: (1) when the engine is operated at ultralean conditions and (2) when an oxidation catalyst is used. Large NO2/NOx ratios may result in additional uncertainty in NOx emissions measurements because the most common technique (chemiluminescence) was developed for low NO2/NOx ratios. In this work, scenarios are explored in which the NO2/NOx ratio can be large. Additionally, three NOx measurement approaches are compared for exhaust with various NO2/NOx ratios. The three measurement approaches are chemiluminescence, chemical cell, and Fourier-transform infrared spectroscopy. A portable analyzer with chemical cell technology was found to be the most accurate for measuring exhaust NOx with large NO2/NOx ratios. PMID:20681434

Olsen, Daniel B; Kohls, Morgan; Arney, Gregg

2010-07-01

229

76 FR 58288 - International Maritime Organization Guidelines for Exhaust Gas Cleaning Systems for Marine...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Pollution by Ships, 1973 as modified by the Protocol of 1978...effective in reducing sulfur oxide emissions as the...marine engines to remove sulfur oxide emissions. Annex...Pollution by Ships, 1973 as modified by the Protocol of 1978...sets requirements for sulfur oxide emissions. A...

2011-09-20

230

E-Alerts: Environmental pollution and control (air pollution and control). E-mail newsletter  

SciTech Connect

Topics of discussion include the following: Air pollution from flue gases, exhaust gases, odors, dust, smog, microorganisms, etc.; Control techniques and equipment; Sampling and analytical techniques, and equipment; Waste gas recovery; Biological and ecological effects; Air pollution chemistry; Acid precipitation; Atmospheric motion; Laws, legislation, and regulations; Public administration; Economics; Land use.

NONE

1999-04-01

231

49 CFR 575.401 - Vehicle labeling of fuel economy, greenhouse gas, and other pollutant emissions information.  

Code of Federal Regulations, 2014 CFR

...labeling of fuel economy, greenhouse gas, and other pollutant emissions information...CONSUMER INFORMATION Energy Independence and Security Act; Consumer Information ...labeling of fuel economy, greenhouse gas, and other pollutant emissions...

2014-10-01

232

40 CFR 1037.241 - Demonstrating compliance with exhaust emission standards for greenhouse gas pollutants.  

Code of Federal Regulations, 2014 CFR

...subpart H of this part. (b) Your vehicle family is deemed not to comply if any vehicle configuration in that family has a modeled...deterioration of battery performance for an electric hybrid vehicle. Where the highest useful life...

2014-07-01

233

Generation of microwave-induced plasmas in automotive exhaust gas mixtures using pulsed microwave energy.  

PubMed

Microwave energy at 2.45 GHz was applied to a mixture of exhaust gases from a petrol engine at atmospheric pressure. It was found that by pulsing the microwave energy with a 50% duty cycle, the average power required to sustain a microwave-induced plasma discharge was decreased by about 40%. The ratio of absorbed to incident power was unaffected. These findings were confirmed for pulse frequencies from 10 to 300 Hz. PMID:15007864

Destefani, Carlos A; Siores, Elias; Murphy, Anthony B

2003-01-01

234

Gas purge-microsyringe extraction: a rapid and exhaustive direct microextraction technique of polycyclic aromatic hydrocarbons from plants.  

PubMed

Gas purge-microsyringe extraction (GP-MSE) is a rapid and exhaustive microextraction technique for volatile and semivolatile compounds. In this study, a theoretical system of GP-MSE was established by directly extracting and analyzing 16 kinds of polycyclic aromatic hydrocarbons (PAHs) from plant samples. On the basis of theoretical consideration, a full factorial experimental design was first used to evaluate the main effects and interactions of the experimental parameters affecting the extraction efficiency. Further experiments were carried out to determine the extraction kinetics and desorption temperature-dependent. The results indicated that three factors, namely desorption temperature (temperature of sample phase) Td, extraction time t, and gas flow rate u, had a significantly positive effect on the extraction efficiency of GP-MSE for PAHs. Extraction processes of PAHs in plant samples followed by first-order kinetics (relative coefficient R(2) of simulation curves were 0.731-1.000, with an average of 0.958 and 4.06% relative standard deviation), and obviously depended on the desorption temperature. Furthermore, the effect of the matrix was determined from the difference in Eapp,d. Finally, satisfactory recoveries of 16 PAHs were obtained using optimal parameters. The study demonstrated that GP-MSE could provide a rapid and exhaustive means of direct extraction of PAHs from plant samples. The extraction kinetics were similar that of the inverse process of the desorption kinetics of the sample phase. PMID:24296142

Wang, Juan; Yang, Cui; Li, Huijie; Piao, Xiangfan; Li, Donghao

2013-12-17

235

Effects of Propane/Natural Gas Blended Fuels on Gas Turbine Pollutant Emissions  

SciTech Connect

Liquefied natural gas (LNG) imports to the U.S. are expected to grow significantly over the next 10-15 years. Likewise, it is expected that changes to the domestic gas supply may also introduce changes in natural gas composition. As a result of these anticipated changes, the composition of fuel sources may vary significantly from conventional domestic natural gas supplies. This paper will examine the effects of fuel variability on pollutant emissions for premixed gas turbine conditions. The experimental data presented in this paper have been collected from a pressurized single injector combustion test rig at the National Energy Technology Laboratory (NETL). The tests are conducted at 7.5 atm with a 588 K air preheat. A propane blending facility is used to vary the Wobbe Index of the site natural gas. The results indicate that propane addition of about five (vol.) percent does not lead to a significant change in the observed NOx or CO emissions. These results are different from data collected on some engine applications and potential reasons for these differences will be described.

Straub, D.L.; Ferguson, D.H.; Casleton, K.H.; Richards, G.A.

2007-03-01

236

Detection of ethene and other hydrocarbons in gas turbine engine exhaust using non-intrusive FTIR spectroscopy  

NASA Astrophysics Data System (ADS)

As part of the EU funded project AEROJET2, a number of gas turbine engine tests were performed in different facilities around Europe. At Farnborough, UK a Spey engine was used to test a suite of prototype optically based instrumentation designed to measure exhaust gas emissions without using extractive probe systems. In addition to the AEROJET 2 prototype instrumentation, a Bruker Equinox 55 Fourier transform infrared (FTIR) spectrometer was used to obtain infrared spectra of the exhaust plume both in emission and absorption mode. The Bruker FTIR spectrometer was fitted with a periscope system so that different lines of sight could be monitored in the plume in a vertical plane 25 cm downstream from the nozzle exit and 20 cm upstream of the center line of sight of the AEROJET 2 prototype instrumentation. DERA (now QinetiQ) provided exhaust gas analysis data for different engine running conditions using samples extracted from the plume with an intrusive probe. The probe sampled along a horizontal plane across the centerline of the engine 45 cm downstream of the nozzle exit. The Bruker spectrometer used both InSb (indium antimonide) and MCT (mercury-cadmium-telluride) detectors to maximize the sensitivity across the IR range 600-4000 cm-1. Typically, CO2 and H2O IR signatures dominate the observed spectra of the plume. However, the engine tests showed that at low power engine conditions spectral features associated with CO around 2147 cm-1 and with hydrocarbons could be observed at around 3000 cm-1. In particular the presence of ethene (C2H2) was detected from observation of its characteristic in and out of plane vibration mode at 949 cm-1. At high engine powers the presence of NO was detected at 1900.3 cm-1. Species concentrations were calculated using a slab model for each line of sight compared against reference spectra. The engine plume was assumed to be symmetric about the centerline. On this basis, data from the extractive sampling gas analysis that had been obtained by traversing the probe across a horizontal plane through the centerline could be compared with non-intrusive measurements made by scanning vertically. Adjustments have been made to account for the 20 cm downstream offset in measurement planes of the probe and the spectrometer behind the nozzle exit.

Arrigone, Giovanni M.; Welch, Michael A.; Hilton, Moira; Miller, Michael N.; Wilson, Christopher W.

2003-04-01

237

METHANOL MEASUREMENT IN AUTO EXHAUST USING A GAS-FILTER CORRELATION SPECTROMETER  

EPA Science Inventory

Spectroscopic methods offer an alternative to wet chemical methods for analysis of methanol emissions from automobiles. The gas filter correlation infrared optical analysis approach appears very promising. The report describes the gas correlation optical system constructed to ana...

238

40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2010 CFR

...performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine...Methane Measurement Using Gas Chromatography.” (Incorporated by reference pursuant...manufacturer has the option of using gas chromatography to measure NMHC through direct...

2010-07-01

239

40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2012 CFR

...performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine...Methane Measurement Using Gas Chromatography.” (Incorporated by reference pursuant...manufacturer has the option of using gas chromatography to measure NMHC through direct...

2012-07-01

240

40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2013 CFR

...performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine...Methane Measurement Using Gas Chromatography.” (Incorporated by reference pursuant...manufacturer has the option of using gas chromatography to measure NMHC through direct...

2013-07-01

241

40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.  

Code of Federal Regulations, 2011 CFR

...performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine...Methane Measurement Using Gas Chromatography.” (Incorporated by reference pursuant...manufacturer has the option of using gas chromatography to measure NMHC through direct...

2011-07-01

242

CONTROL OF UTILITY BOILER AND GAS TURBINE POLLUTANT EMISSIONS BY COMBUSTION MODIFICATION - PHASE I  

EPA Science Inventory

The report gives results of a field study to assess the applicability of combustion modification techniques to control NOx and other pollutant emissions from utility boilers and gas turbines without causing deleterious side effects. Comprehensive, statistically designed tests wer...

243

In Utero Exposure to Diesel Exhaust Air Pollution Promotes Adverse Intrauterine Conditions, Resulting in Weight Gain, Altered Blood Pressure, and Increased Susceptibility to Heart Failure in Adult Mice  

PubMed Central

Exposure to fine particulate air pollution (PM2.5) is strongly associated with cardiovascular morbidity and mortality. Exposure to PM2.5 during pregnancy promotes reduced birthweight, and the associated adverse intrauterine conditions may also promote adult risk of cardiovascular disease. Here, we investigated the potential for in utero exposure to diesel exhaust (DE) air pollution, a major source of urban PM2.5, to promote adverse intrauterine conditions and influence adult susceptibility to disease. We exposed pregnant female C57Bl/6J mice to DE (?300 µg/m3 PM2.5, 6 hrs/day, 5 days/week) from embryonic day (E) 0.5 to 17.5. At E17.5 embryos were collected for gravimetric analysis and assessed for evidence of resorption. Placental tissues underwent pathological examination to assess the extent of injury, inflammatory cell infiltration, and oxidative stress. In addition, some dams that were exposed to DE were allowed to give birth to pups and raise offspring in filtered air (FA) conditions. At 10-weeks of age, body weight and blood pressure were measured. At 12-weeks of age, cardiac function was assessed by echocardiography. Susceptibility to pressure overload-induced heart failure was then determined after transverse aortic constriction surgery. We found that in utero exposure to DE increases embryo resorption, and promotes placental hemorrhage, focal necrosis, compaction of labyrinth vascular spaces, inflammatory cell infiltration and oxidative stress. In addition, we observed that in utero DE exposure increased body weight, but counterintuitively reduced blood pressure without any changes in baseline cardiac function in adult male mice. Importantly, we observed these mice to have increased susceptibility to pressure-overload induced heart failure, suggesting this in utero exposure to DE ‘reprograms’ the heart to a heightened susceptibility to failure. These observations provide important data to suggest that developmental exposure to air pollution may strongly influence adult susceptibility to cardiovascular disease. PMID:24533117

Weldy, Chad S.; Liu, Yonggang; Liggitt, H. Denny; Chin, Michael T.

2014-01-01

244

In utero exposure to diesel exhaust air pollution promotes adverse intrauterine conditions, resulting in weight gain, altered blood pressure, and increased susceptibility to heart failure in adult mice.  

PubMed

Exposure to fine particulate air pollution (PM?.?) is strongly associated with cardiovascular morbidity and mortality. Exposure to PM?.? during pregnancy promotes reduced birthweight, and the associated adverse intrauterine conditions may also promote adult risk of cardiovascular disease. Here, we investigated the potential for in utero exposure to diesel exhaust (DE) air pollution, a major source of urban PM?.?, to promote adverse intrauterine conditions and influence adult susceptibility to disease. We exposed pregnant female C57Bl/6J mice to DE (?300 µg/m³ PM?.?, 6 hrs/day, 5 days/week) from embryonic day (E) 0.5 to 17.5. At E17.5 embryos were collected for gravimetric analysis and assessed for evidence of resorption. Placental tissues underwent pathological examination to assess the extent of injury, inflammatory cell infiltration, and oxidative stress. In addition, some dams that were exposed to DE were allowed to give birth to pups and raise offspring in filtered air (FA) conditions. At 10-weeks of age, body weight and blood pressure were measured. At 12-weeks of age, cardiac function was assessed by echocardiography. Susceptibility to pressure overload-induced heart failure was then determined after transverse aortic constriction surgery. We found that in utero exposure to DE increases embryo resorption, and promotes placental hemorrhage, focal necrosis, compaction of labyrinth vascular spaces, inflammatory cell infiltration and oxidative stress. In addition, we observed that in utero DE exposure increased body weight, but counterintuitively reduced blood pressure without any changes in baseline cardiac function in adult male mice. Importantly, we observed these mice to have increased susceptibility to pressure-overload induced heart failure, suggesting this in utero exposure to DE 'reprograms' the heart to a heightened susceptibility to failure. These observations provide important data to suggest that developmental exposure to air pollution may strongly influence adult susceptibility to cardiovascular disease. PMID:24533117

Weldy, Chad S; Liu, Yonggang; Liggitt, H Denny; Chin, Michael T

2014-01-01

245

Determination of the characteristics of gas-dust flow of exhaust gases from the gas-turbine plant to the reconstructed boilers of the Bereza State District Power Station  

NASA Astrophysics Data System (ADS)

Flow of the exhaust gases in intricately shaped gas ducts between the gas-turbine unit and the steam boiler in the steam-gas plant of the Bereza State District Power Station has been investigated. The distribution of the gasdynamic parameters of three-dimensional turbulent flow of exhaust gases in channels of different geometries has been studied. The influence of certain structural elements of the gas duct on the hydrodynamic characteristics of flow has been considered. The amplitude-frequency analysis of the natural oscillations of the gasdynamic parameters in different cross sections of the channel has been performed using fast Fourier transformation.

Bachurinskii, A. N.; Smetannikov, A. S.; Stankevich, Yu. A.; Stanchits, L. K.; Stepanov, K. L.; Strelkov, A. I.

2006-05-01

246

Market structure and exhaustible resources: The case of natural gas and crude oil in California  

NASA Astrophysics Data System (ADS)

Using a dataset of natural gas and crude oil production in the state of California, evidence shows overextraction incentives among market participants that shared a common pool. Due to these incentives the supply of gas and crude oil extraction tends to become more inelastic as the number of firms in the pool increases. Using an instrumental variables estimation of the supply function, the results show that the common pool externality caused an average overproduction rate of 11% and 4% over the 1977--2001 period, in natural gas and crude oil, respectively. These figures imply 1 year and 4 years of additional production for natural gas and crude oil, respectively.

Czastkiewicz, Carolina

247

Dynamic characteristics of a hydrostatic gas bearing driven by oscillating exhaust pressure  

NASA Technical Reports Server (NTRS)

Vibration of a statically loaded, inherently compensated hydrostatic journal bearing due to oscillating exhaust pressure is investigated. Both angular and radial vibration modes are analyzed. The time-dependent Reynolds equation governing the pressure distribution between the oscillating journal and sleeve is solved together with the journal equation of motion to obtain the response characteristics of the bearing. The Reynolds equation and the equation of motion are simplified by applying regular perturbation theory for small displacements. The numerical solutions of the perturbation equations are obtained by discretizing the pressure field using finite-difference aproximations with a discrete, nonuniform line-source model which excludes effects due to feeding hole volume. An iterative scheme is used to simultaneously satisfy the equations of motion for the journal. The results presented include Bode plots of bearing-oscillation gain and phase for a particular bearing configuration for various combinations of parameters over a range of frequencies, including the resonant frequency.

Watkins, C. B.; Eronini, I. E.; Branch, H. D.

1984-01-01

248

The Use of Exhaust Gas Recirculation to Optimize Fuel Economy and Minimize Emission in Engines Operating on E85 Fuel  

SciTech Connect

This report summarizes activities conducted for the project “The Use of Exhaust Gas Recirculation to Optimized Fuel Economy and Minimize Emissions in Engines Operating on E85 Fuel” under COOPERATIVE AGREEMENT NUMBER DE-FC26-07NT43271, which are as outlined in the STATEMENT OF PROJECT OBJECTIVES (SOPO) dated March 2007 and in the supplemental SOPO dated October 2010. The project objective was to develop and demonstrate an internal combustion engine that is optimized for E85 (85% ethanol and 15% gasoline) fuel operation to achieve substantially improved fuel economy while operating with E85 fuel and that is also production viable in the near- to medium-term. The key engine technology selected for research and development was turbocharging, which is known to improve fuel economy thru downsizing and is in particular capable of exploiting ethanol fuel’s characteristics of high octane number and high latent heat of vaporization. The engine further integrated synergistic efficiency improving technologies of cooled exhaust gas recirculation (EGR), direct fuel injection and dual continuously variable intake and exhaust cam phasers. On the vehicle level, fuel economy was furthered thru powertrain system optimization by mating a state-of-the-art six-speed automatic transmission to the engine. In order to achieve the project’s objective of near- to medium-term production viability, it was essential to develop the engine to be flex-fuel capable of operating with fuels ranging from E0 (0% ethanol and 100% gasoline) to E85 and to use three-way type of catalyst technology for exhaust aftertreatment. Within these scopes, various technologies were developed through systems approach to focus on ways to help accelerate catalyst light-off. Significant amount of development took place during the course of the project within General Motors, LLC. Many prototype flex-fuel engines were designed, built and developed with various hardware configurations selected to achieve the project goals. Several flex-fuel demonstration vehicles were designed and built for carrying out calibration development and final testing to quantify the technology merits. Based on the extensive test results collected from dynamometer and vehicle testing, the fuel economy benefits of cooled EGR from the intended level of turbocharger technology were quantified. When combined with turbo downsizing, the FE benefits are considered large enough for E0 fuel as well as for E85 fuel to warrant further development of the technology beyond the current proof-of-concept level to a level that can meet production driveability quality and durability requirements in order to meet customers’ expectations. Cold-start cart test results from the emissions segment of the project were positive, confirming the assumption of faster thermal response of turbo exhaust system for emissions reductions for both E0 and E85 fuels. Vehicle emissions test results directionally correlated to the cold-start cart findings. The limited number of test runs did demonstrate the potentials of meeting stringent emission standards, however, they did not comprehend the factors such as hardware variability and long-term durability, 3 which are essential for mass production to satisfy customers’ expectations. It is therefore recommended, moving forward, durability concerns over turbocharger, EGR system and aftertreatment system, which would likely impact production viability, should be addressed. The data moreover suggested that further FE increase is likely with turbocharger technology advancement.

Wu, Ko-Jen

2011-12-31

249

Semiconducting Metal Oxide Based Sensors for Selective Gas Pollutant Detection  

PubMed Central

A review of some papers published in the last fifty years that focus on the semiconducting metal oxide (SMO) based sensors for the selective and sensitive detection of various environmental pollutants is presented. PMID:22408500

Kanan, Sofian M.; El-Kadri, Oussama M.; Abu-Yousef, Imad A.; Kanan, Marsha C.

2009-01-01

250

Pollution  

ERIC Educational Resources Information Center

Presents the material given in one class period in a course on Environmental Studies at Chesterfield School, England. The topics covered include air pollution, water pollution, fertilizers, and insecticides. (JR)

Rowbotham, N.

1973-01-01

251

Fast and quantitative measurement of benzene, toluene and C 2-benzenes in automotive exhaust during transient engine operation with and without catalytic exhaust gas treatment  

Microsoft Academic Search

Time-Resolved Chemical Ionization Mass Spectrometry (CIMS) has been used to investigate the emission profiles of benzene, toluene and the C2-benzenes (xylenes and ethyl benzene) in automotive exhaust during transient engine operation. On-line emission measurements with a frequency of 1–5Hz clearly identified the critical driving conditions that are mainly responsible for the overall aromatic hydrocarbon emissions. The passenger car, equipped with

Norbert V. Heeb; Anna-Maria Forss; Christian Bach

1999-01-01

252

On the Performance and Operability of GE’s Dry Low NO x Combustors utilizing Exhaust Gas Recirculation for PostCombustion Carbon Capture  

Microsoft Academic Search

The capture and sequestration of CO2 will be necessary to mitigate CO2 emissions from fossil fuel (coal, oil, natural gas or biomass) power generation facilities in a carbon constrained world. Post combustion carbon capture is a viable technology alternative to reduce CO2 emissions from power plants in the short term. The CO2 concentration in the exhaust gases of natural fired

Andrei T. Evulet; Ahmed M. ELKady; Anthony R. Branda; Daniel Chinn

2009-01-01

253

Extending Exhaust Gas Recirculation Limits in Diesel Engines Robert M. Wagner, Johney B. Green, Jr., John M. Storey, and C. Stuart Daw  

E-print Network

1 Extending Exhaust Gas Recirculation Limits in Diesel Engines Robert M. Wagner, Johney B. Green) for reduced nitro- gen oxide emissions from diesel engines. The research objective is to develop fundamental of HC and PM emissions. The result is that diesel engines must be typically operated significantly be

Tennessee, University of

254

An experimental study on latent heat recovery of exhaust wet flue gas  

Microsoft Academic Search

The experiment was conducted to investigate the heat transfer performance of wet flue gas in a vertical tube. The factors\\u000a influencing the convective condensation of wet flue gas were experimentally investigated. The measured results indicate that\\u000a the convective heat transfer of bulk flow and condensation heat transfer of vapor have significant contribution to the total\\u000a heat transfer and the dominant

Li Jia; Xiaoping Li; Jindong Sun; Xiaofeng Peng

2002-01-01

255

78 FR 51724 - California State Motor Vehicle Pollution Control Standards; Tractor-Trailer Greenhouse Gas...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Vehicle Pollution Control Standards; Tractor-Trailer Greenhouse Gas Regulation...has notified EPA that it has adopted a tractor-trailer greenhouse gas emission regulation...box-type trailers and to new and in-use tractors that haul such trailers on...

2013-08-21

256

CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME 1. TECHNICAL REPORT  

EPA Science Inventory

The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

257

Gas-particle partitioning of primary organic aerosol emissions: (1) Gasoline vehicle exhaust  

NASA Astrophysics Data System (ADS)

The gas-particle partitioning of the primary organic aerosol (POA) emissions from fifty-one light-duty gasoline vehicles (model years 1987-2012) was investigated at the California Air Resources Board Haagen-Smit Laboratory. Each vehicle was operated over the cold-start unified cycle on a chassis dynamometer and its emissions were sampled using a constant volume sampler. Four independent yet complementary approaches were used to investigate POA gas-particle partitioning: sampling artifact correction of quartz filter data, dilution from the constant volume sampler into a portable environmental chamber, heating in a thermodenuder, and thermal desorption/gas chromatography/mass spectrometry analysis of quartz filter samples. This combination of techniques allowed gas-particle partitioning measurements to be made across a wide range of atmospherically relevant conditions - temperatures of 25-100 °C and organic aerosol concentrations of <1-600 ?g m-3. The gas-particle partitioning of the POA emissions varied continuously over this entire range of conditions and essentially none of the POA should be considered non-volatile. Furthermore, for most vehicles, the low levels of dilution used in the constant volume sampler created particle mass concentrations that were greater than a factor of 10 or higher than typical ambient levels. This resulted in large and systematic partitioning biases in the POA emission factors compared to more dilute atmospheric conditions, as the POA emission rates may be over-estimated by nearly a factor of four due to gas-particle partitioning at higher particle mass concentrations. A volatility distribution was derived to quantitatively describe the measured gas-particle partitioning data using absorptive partitioning theory. Although the POA emission factors varied by more than two orders of magnitude across the test fleet, the vehicle-to-vehicle differences in gas-particle partitioning were modest. Therefore, a single volatility distribution can be used to quantitatively describe the gas-particle partitioning of the entire test fleet. This distribution is designed to be applied to quartz filter POA emission factors in order to update emissions inventories for use in chemical transport models.

May, Andrew A.; Presto, Albert A.; Hennigan, Christopher J.; Nguyen, Ngoc T.; Gordon, Timothy D.; Robinson, Allen L.

2013-10-01

258

METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 11: COMPRESSOR DRIVER EXHAUST  

EPA Science Inventory

The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

259

LOW COST IMAGER FOR POLLUTANT GAS LEAK DETECTION - PHASE I  

EPA Science Inventory

Infrared (IR) imaging is the best method for detecting leaks of pollutant gases, but current technology based on cooled IR imagers is far too expensive ($75,000 to $150,000) for everyday field use by those who need it to meet regulatory limits—electric and petrochemical ...

260

Fuel-air mixing apparatus for reducing gas turbine combustor exhaust emissions  

NASA Technical Reports Server (NTRS)

A fuel-air mixer for use in a combustion chamber of a gas turbine engine is provided. The fuel air mixing apparatus comprises an annular fuel injector having a plurality of discrete plain jet orifices, a first swirler wherein the first swirler is located upstream from the fuel injector and a second swirler wherein the second swirler is located downstream from the fuel injector. The plurality of discrete plain jet orifices are situated between the highly swirling airstreams generated by the two radial swirlers. The distributed injection of the fuel between two highly swirling airstreams results in rapid and effective mixing to the desired fuel-air ratio and prevents the formation of local hot spots in the combustor primary zone. A combustor and a gas turbine engine comprising the fuel-air mixer of the present invention are also provided as well as a method using the fuel-air mixer of the present invention.

Zupanc, Frank J. (Inventor); Yankowich, Paul R. (Inventor)

2006-01-01

261

Flow characteristics in the exhaust of a pulsed megawatt gas fed arc  

NASA Technical Reports Server (NTRS)

The transient flow generated by a pulsed, megawatt-level, gas-fed arc with an applied magnetic nozzle has been examined with a new design piezoelectric pressure transducer. Sensor thermal conduction and accelerations have been examined and eliminated in the 500 microsec period of plasma flow. Existence of a large magnitude cold gas pressure front of 20 microsec duration has been reconfirmed and its relationship to the following plasma flow of about 200 microsec duration has been examined for the first time. At a point 30 cm from the arc source, initially near vacuum conditions (typically with an arc current of 11.2 kA and 1 tesla applied magnetic field), a pressure pulse of unionized gas with a magnitude of 10,000 N/sq m is followed by plasma flows with nearly constant impact pressure of 1000 N/sq m. Pressure and number density in this plasma region are seen to decrease with applied magnetic field strength.

Michels, C. J.; York, T. M.

1973-01-01

262

Recommended launch-hold criteria for protecting public health from hydrogen chloride (HC1) gas produced by rocket exhaust  

SciTech Connect

Solid-fuel rocket motors used by the United States Air Force (USAF) to launch missiles and spacecraft can produce ambient-air concentrations of hydrogen chloride (HCI) gas. The HCI gas is a reaction product exhausted from the rocket motor during normal launch or emitted as a result of a catastrophic abort destroying the launch vehicle. Depending on the concentration in ambient air, the HCI gas can be irritating or toxic to humans. The diagnostic and complex-terrain wind field and particle dispersion model used by the Lawrence Livermore National Laboratory`s (LLNL`s) Atmospheric Release Advisory Capability (ARAC) Program was applied to the launch of a Peacekeeper missile from Vandenberg Air Force Base (VAFB) in California. Results from this deterministic model revealed that under specific meteorological conditions, cloud passage from normal-launch and catastropic-abort situations can yield measureable ground-level air concentrations of HCI where the general public is located. To protect public health in the event of such cloud passage, scientifically defensible, emergency ambient-air concentration limits for HCI were developed and recommended to the USAF for use as launch-hold criteria. Such launch-hold criteria are used to postpone a launch unless the forecasted meteorological conditions favor the prediction of safe ground-level concentrations of HCl for the general public. The recommended concentration limits are a 2 ppM 1-h time-weighted average (TWA) concentration constrained by a 1-min 10-ppM average concentration. This recommended criteria is supported by human dose-response information, including data for sensitive humans (e.g., asthmatics), and the dose response exhibited experimentally by animal models with respiratory physiology or responses considered similar to humans.

Daniels, J.I.; Baskett, R.L.

1995-11-01

263

An integrated exhaust gas analysis system with self-contained data processing and automatic calibration  

NASA Technical Reports Server (NTRS)

An integrated gas analysis system designed to operate in automatic, semiautomatic, and manual modes from a remote control panel is described. The system measures the carbon monoxide, oxygen, water vapor, total hydrocarbons, carbon dioxide, and oxides of nitrogen. A pull through design provides increased reliability and eliminates the need for manual flow rate adjustment and pressure correction. The system contains two microprocessors to range the analyzers, calibrate the system, process the raw data to units of concentration, and provides information to the facility research computer and to the operator through terminal and the control panels. After initial setup, the system operates for several hours without significant operator attention.

Anderson, R. C.; Summers, R. L.

1981-01-01

264

Combatting urban air pollution through Natural Gas Vehicle (NGV) analysis, testing, and demonstration  

SciTech Connect

Deteriorating urban air quality ranks as a top concern worldwide, since air pollution adversely affects both public health and the environment. The outlook for improving air quality in the world`s megacities need not be bleak, however, The use of natural gas as a transportation fuel can measurably reduce urban pollution levels, mitigating chronic threats to health and the environment. Besides being clean burning, natural gas vehicles (NGVs) are economical to operate and maintain. The current cost of natural gas is lower than that of gasoline. Natural gas also reduces the vehicle`s engine wear and noise level, extends engine life, and decreases engine maintenance. Today, about 700,000 NGVs operate worldwide, the majority of them converted from gasoline or diesel fuel. This article discusses the economic, regulatory and technological issues of concern to the NGV industry.

NONE

1995-03-01

265

Analysis of the Mid-Infrared Spectrum of the Exhaust Gas From an Atmospheric Pressure Plasma Jet (APPJ) Working With an Argon–Air Mixture  

Microsoft Academic Search

The mid-infrared (IR) absorption spectrum of the exhaust gas of an atmospheric pressure plasma jet operated in Ar with the admixture of 0.1% of air has been monitored in the spectral region from 4000 to 750 cm-1. The absorption features of CO2, CO, NO, NO2, N2O, HNO2, and HNO3 were identified using a Fourier transform IR spectrometer combined with a

Andrei V. Pipa; Jürgen Ropcke

2009-01-01

266

Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems  

Microsoft Academic Search

Development of a pulsed quantum cascade laser (QCL)-based spectroscopic trace-gas sensor for sub-part-per-million detection of nitric oxide (NO) and capable of monitoring other molecular species such as CO2, H2O, and NH3 in industrial combustion exhaust systems is reported. Rapid frequency modulation is applied to the QCL to minimize the influence of fluctuating non-selective absorption. A novel method utilizes only a

G. Wysocki; A. A. Kosterev; F. K. Tittel

2005-01-01

267

Miniaturized instrumentation for routine measurement of aerosol and gas phase pollution by lightweight autonomous unmanned aircraft.  

NASA Astrophysics Data System (ADS)

The upcoming California AUAV Pollution Profiling project (CAPPS) will routinely monitor the vertical distribution of aerosol and gas pollutants over California during 2008 using autonomous lightweight unmanned aircraft. The measurements will be used to evaluate the impact of pollutants on California's climate, detect long range transport, and to validate satellite measurements. Proven miniaturized instrumentation for collecting aerosol parameters (concentration, size distribution, absorption), atmospheric solar radiation (flux, heating rates, albedo) and meteorological parameters (thermodynamic structure, water vapor) that were flown during previous studies will be deployed. Validation of these instruments is reviewed. New miniaturized instruments to collect the concentration of gas species are being developed to compliment these established measurements. An ozone monitor with a resolution of 2 ppb has been successfully integrated into the flight package. Results from the laboratory validation of this instrument are presented. In addition, progress on a miniaturized carbon monoxide sensor and NOx sensor are also presented.

Corrigan, C. E.; Ramanathan, V.; Roberts, G.; Ramana, M. V.

2007-12-01

268

CONTROL OF UTILITY BOILER AND GAS TURBINE POLLUTANT EMISSIONS BY COMBUSTION MODIFICATION--PHASE II  

EPA Science Inventory

The report gives results of Phase II of a field study to assess the applicability of combustion modification (CM) techniques to control NOx and other pollutant emissions from utility boilers and gas turbines without causing deleterious side effects. Comprehensive, statistically d...

269

A Study on Pollutant Emission Through Gas Consumption in the Hong Kong Hotel Industry  

Microsoft Academic Search

A survey of 11 hotels in Hong Kong was carried out to collect three years' energy consumption data. Regression analysis indicated that gross floor area was a major and statistically acceptable factor in explaining the gas consumption in new hotels. Based on past consumption data and some established pollutant emission factors, the amount of sulphur dioxides, nitrogen dioxides, carbon dioxides

Wilco W. Chan; Joseph C. Lam

2002-01-01

270

Greenhouse gas emission and groundwater pollution potentials of soils amended with raw and carbonized swine solids  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this research is to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with raw swine solids and swine biochars made from different thermochemical conditions. Triplicate sets of small pots were designed: 1) control soil with a 50/50 mixture o...

271

Groundwater pollution potential and greenhouse gas emission from soils amended with different swine biochars  

Technology Transfer Automated Retrieval System (TEKTRAN)

Although there exist numerous research studies in the literature on greenhouse gas emission and groundwater pollution potentials of soils amended with plant-based biochar made from traditional dry pyrolysis (hereafter referred as pyrochar), a very few such studies exist for hydrochar made from hydro...

272

Air Pollution  

MedlinePLUS

Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

273

Exhaust purification with on-board ammonia production  

DOEpatents

A method of ammonia production for a selective catalytic reduction system is provided. The method includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream my be converted into ammonia.

Robel, Wade J. (Peoria, IL); Driscoll, James Joshua (Dunlap, IL); Coleman, Gerald N. (Helpston, GB)

2010-10-12

274

Exhaust purification with on-board ammonia production  

DOEpatents

A system of ammonia production for a selective catalytic reduction system is provided. The system includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream may be converted into ammonia.

Robel, Wade J. (Peoria, IL); Driscoll, James Joshua (Dunlap, IL); Coleman, Gerald N. (Peterborough, GB)

2008-05-13

275

Black carbon from ships: a review of the effects of ship speed, fuel quality and exhaust gas scrubbing  

NASA Astrophysics Data System (ADS)

The International Maritime Organization (IMO) has moved to address the health and climate impact of the emissions from the combustion of low-quality residual fuels within the commercial shipping industry. Fuel sulfur content (FS) limits and an efficiency design index for future ships are examples of such IMO actions. The impacts of black carbon (BC) emissions from shipping are now under review by the IMO, with a particular focus on the potential impacts of future Arctic shipping. Recognizing that associating impacts with BC emissions requires both ambient and onboard observations, we provide recommendations for the measurement of BC. We also evaluate current insights regarding the effect of ship speed (engine load), fuel quality and exhaust gas scrubbing on BC emissions from ships. Observations demonstrate that BC emission factors (EFBC) increases 3 to 6 times at very low engine loads (<25% compared to EFBC at 85-100% load); absolute BC emissions (per nautical mile of travel) also increase up to 100% depending on engine load, even with reduced load fuel savings. If fleets were required to operate at lower maximum engine loads, presumably associated with reduced speeds, then engines could be re-tuned, which would reduce BC emissions. Ships operating in the Arctic are likely running at highly variable engine loads (25-100%) depending on ice conditions and ice breaking requirements. The ships operating at low load may be emitting up to 50% more BC than they would at their rated load. Such variable load conditions make it difficult to assess the likely emissions rate of BC. Current fuel sulfur regulations have the effect of reducing EFBC by an average of 30% and potentially up to 80% regardless of engine load; a removal rate similar to that of scrubbers. Uncertainties among current observations demonstrate there is a need for more information on (a) the impact of fuel quality on EFBC using robust measurement methods and (b) the efficacy of scrubbers for the removal of particulate matter by size and composition.

Lack, D. A.; Corbett, J. J.

2012-01-01

276

Black carbon from ships: a review of the effects of ship speed, fuel quality and exhaust gas scrubbing  

NASA Astrophysics Data System (ADS)

The International Maritime Organization (IMO) has moved to address the health and climate impact of the emissions from the combustion of low-quality residual fuels within the commercial shipping industry. Fuel sulfur content (FS) limits and an efficiency design index for future ships are examples of such IMO actions. The impacts of black carbon (BC) emissions from shipping are now under review by the IMO, with a particular focus on the potential impacts of future Arctic shipping. Recognizing that associating impacts with BC emissions requires both ambient and onboard observations, we provide recommendations for the measurement of BC. We also evaluate current insights regarding the effect of ship speed (engine load), fuel quality and exhaust gas scrubbing on BC emissions from ships. Observations demonstrate that BC emission factors (EFBC) increases 3 to 6 times at very low engine loads (<25% compared to EFBC at 85-100% load); absolute BC emissions (per nautical mile of travel) also increase up to 100% depending on engine load, even with reduced load fuel savings. If fleets were required to operate at lower maximum engine loads, presumably associated with reduced speeds, then engines could be re-tuned, which would reduce BC emissions. Ships operating in the Arctic are likely running at highly variable engine loads (25-100%) depending on ice conditions and ice breaking requirements. The ships operating at low load may be emitting up to 50% more BC than they would at their rated load. Such variable load conditions make it difficult to assess the likely emissions rate of BC. Current fuel sulfur regulations have the effect of reducing EFBC by an average of 30% and potentially up to 80% regardless of engine load; a removal rate similar to that of scrubbers. Uncertainties among current observations demonstrate there is a need for more information on a) the impact of fuel quality on EFBC using robust measurement methods and b) the efficacy of scrubbers for the removal of particulate matter by size and composition.

Lack, D. A.; Corbett, J. J.

2012-05-01

277

Payload dose rate from direct beam radiation and exhaust gas fission products. [for nuclear engine for rocket vehicles  

NASA Technical Reports Server (NTRS)

A study was made to determine the dose rate at the payload position in the NERVA System (1) due to direct beam radiation and (2) due to the possible effect of fission products contained in the exhaust gases for various amounts of hydrogen propellant in the tank. Results indicate that the gamma radiation is more significant than the neutron flux. Under different assumptions the gamma contribution from the exhaust gases was 10 to 25 percent of total gamma flux.

Capo, M. A.; Mickle, R.

1975-01-01

278

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objectives of this report period were to complete the development of the Gas Generator design, which was done; fabricate and test of the non-polluting unique power turbine drive gas Gas Generator, which has been postponed. Focus during this report period has been to complete the brazing and bonding necessary to fabricate the Gas Generator hardware, continue making preparations for fabricating and testing the Gas Generator, and continuing the fabrication of the Gas Generator hardware and ancillary hardware in preparation for the test program. Fabrication is more than 95% complete and is expected to conclude in early May 2002. the test schedule was affected by relocation of the testing to another test supplier. The target test date for hot fire testing is now not earlier than June 15, 2002.

Unknown

2002-03-31

279

Controlling exhaust gas recirculation  

DOEpatents

In controlling an engine, an amount of an intake charge provided, during operation of the engine, to a combustion chamber of the engine is determined. The intake charge includes an air component, a fuel component and a diluent component. An amount of the air component of the intake charge is determined. An amount of the diluent component of the intake charge is determined utilizing the amount of the intake charge, the amount of the air component and, in some instances, the amount of the fuel component. An amount of a diluent supplied to the intake charge is adjusted based at least in part on the determined amount of diluent component of the intake charge.

Zurlo, James Richard (Madison, WI); Konkle, Kevin Paul (West Bend, WI); May, Andrew (Milwaukee, WI)

2012-01-31

280

Predictive Model for Pollutant Dispersion from Gas Flaring: A Case Study of Oil Producing Area of Nigeria  

Microsoft Academic Search

Nigeria has recorded a long history of petroleum exploration, but gas flaring associated with this activity is contributing immensely to air pollution in the Niger-Delta area and beyond. Hence, this work is aimed at quantifying the extent of air pollution from gas flaring, i.e., CO2, CO, SO2, NO2, and THC. Volume of gas flare and conditions of flare as well

A. S. Abdulkareem; J. O. Odigure; S. Abenege

2009-01-01

281

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objectives of this report period were to continue the development of the Gas Generator design, to complete the hardware and ancillary hardware fabrication, and commence the Test Preparations for the testing of the non-polluting unique power turbine drive gas generator. Focus during this report period has been on testing the Gas Generator. Because of unacceptable delays encountered in a previously competitively selected test site, CES initiated a re-competition of our testing program and selected an alternate test site. Following that selection, CES used all available resources to make preparations for testing the 10 Mw Gas Generator at the new testing site facilities of NTS at Saugus, CA. A substantial portion of this report period was devoted to Testing Preparations, i.e. test facility development, cold- flow testing, calibration testing, performing igniter ignition testing, and then commencement of the completely assembled Gas Generator Assembly Testing, in process at this writing.

Unknown

2001-10-30

282

High winter ozone pollution from carbonyl photolysis in an oil and gas basin  

NASA Astrophysics Data System (ADS)

The United States is now experiencing the most rapid expansion in oil and gas production in four decades, owing in large part to implementation of new extraction technologies such as horizontal drilling combined with hydraulic fracturing. The environmental impacts of this development, from its effect on water quality to the influence of increased methane leakage on climate, have been a matter of intense debate. Air quality impacts are associated with emissions of nitrogen oxides (NOx = NO + NO2) and volatile organic compounds (VOCs), whose photochemistry leads to production of ozone, a secondary pollutant with negative health effects. Recent observations in oil- and gas-producing basins in the western United States have identified ozone mixing ratios well in excess of present air quality standards, but only during winter. Understanding winter ozone production in these regions is scientifically challenging. It occurs during cold periods of snow cover when meteorological inversions concentrate air pollutants from oil and gas activities, but when solar irradiance and absolute humidity, which are both required to initiate conventional photochemistry essential for ozone production, are at a minimum. Here, using data from a remote location in the oil and gas basin of northeastern Utah and a box model, we provide a quantitative assessment of the photochemistry that leads to these extreme winter ozone pollution events, and identify key factors that control ozone production in this unique environment. We find that ozone production occurs at lower NOx and much larger VOC concentrations than does its summertime urban counterpart, leading to carbonyl (oxygenated VOCs with a C = O moiety) photolysis as a dominant oxidant source. Extreme VOC concentrations optimize the ozone production efficiency of NOx. There is considerable potential for global growth in oil and gas extraction from shale. This analysis could help inform strategies to monitor and mitigate air quality impacts and provide broader insight into the response of winter ozone to primary pollutants.

Edwards, Peter M.; Brown, Steven S.; Roberts, James M.; Ahmadov, Ravan; Banta, Robert M.; Degouw, Joost A.; Dubé, William P.; Field, Robert A.; Flynn, James H.; Gilman, Jessica B.; Graus, Martin; Helmig, Detlev; Koss, Abigail; Langford, Andrew O.; Lefer, Barry L.; Lerner, Brian M.; Li, Rui; Li, Shao-Meng; McKeen, Stuart A.; Murphy, Shane M.; Parrish, David D.; Senff, Christoph J.; Soltis, Jeffrey; Stutz, Jochen; Sweeney, Colm; Thompson, Chelsea R.; Trainer, Michael K.; Tsai, Catalina; Veres, Patrick R.; Washenfelder, Rebecca A.; Warneke, Carsten; Wild, Robert J.; Young, Cora J.; Yuan, Bin; Zamora, Robert

2014-10-01

283

High winter ozone pollution from carbonyl photolysis in an oil and gas basin.  

PubMed

The United States is now experiencing the most rapid expansion in oil and gas production in four decades, owing in large part to implementation of new extraction technologies such as horizontal drilling combined with hydraulic fracturing. The environmental impacts of this development, from its effect on water quality to the influence of increased methane leakage on climate, have been a matter of intense debate. Air quality impacts are associated with emissions of nitrogen oxides (NOx = NO + NO2) and volatile organic compounds (VOCs), whose photochemistry leads to production of ozone, a secondary pollutant with negative health effects. Recent observations in oil- and gas-producing basins in the western United States have identified ozone mixing ratios well in excess of present air quality standards, but only during winter. Understanding winter ozone production in these regions is scientifically challenging. It occurs during cold periods of snow cover when meteorological inversions concentrate air pollutants from oil and gas activities, but when solar irradiance and absolute humidity, which are both required to initiate conventional photochemistry essential for ozone production, are at a minimum. Here, using data from a remote location in the oil and gas basin of northeastern Utah and a box model, we provide a quantitative assessment of the photochemistry that leads to these extreme winter ozone pollution events, and identify key factors that control ozone production in this unique environment. We find that ozone production occurs at lower NOx and much larger VOC concentrations than does its summertime urban counterpart, leading to carbonyl (oxygenated VOCs with a C = O moiety) photolysis as a dominant oxidant source. Extreme VOC concentrations optimize the ozone production efficiency of NOx. There is considerable potential for global growth in oil and gas extraction from shale. This analysis could help inform strategies to monitor and mitigate air quality impacts and provide broader insight into the response of winter ozone to primary pollutants. PMID:25274311

Edwards, Peter M; Brown, Steven S; Roberts, James M; Ahmadov, Ravan; Banta, Robert M; deGouw, Joost A; Dubé, William P; Field, Robert A; Flynn, James H; Gilman, Jessica B; Graus, Martin; Helmig, Detlev; Koss, Abigail; Langford, Andrew O; Lefer, Barry L; Lerner, Brian M; Li, Rui; Li, Shao-Meng; McKeen, Stuart A; Murphy, Shane M; Parrish, David D; Senff, Christoph J; Soltis, Jeffrey; Stutz, Jochen; Sweeney, Colm; Thompson, Chelsea R; Trainer, Michael K; Tsai, Catalina; Veres, Patrick R; Washenfelder, Rebecca A; Warneke, Carsten; Wild, Robert J; Young, Cora J; Yuan, Bin; Zamora, Robert

2014-10-16

284

Chemical analysis and ozone formation potential of exhaust from dual-fuel (liquefied petroleum gas/gasoline) light duty vehicles  

NASA Astrophysics Data System (ADS)

Measures must be undertaken to lower the transport sector's contribution to anthropogenic emissions. Vehicles powered by liquefied petroleum gas (LPG) are an option due to their reduced emissions of air pollutants compared to engines with conventional fuels. In the present study, ten different dual-fuel LPG/gasoline light duty vehicles were tested, which all complied with European emission level legislation EURO-4. Tests with LPG and gasoline were performed on a chassis dynamometer by applying the New European Driving Cycle (NEDC) and emission factors and ozone formation potentials of both kinds of fuels were compared. The components investigated comprised regulated compounds, CO 2, volatile hydrocarbons and carbonyls. On-line analysis of aromatic species was carried out by resonance-enhanced multiphoton ionization-time-of-flight mass spectrometry (REMPI-TOFMS). We demonstrate that utilization of LPG can entail some environmental benefits by reducing emissions. However, for dual-fuel LPG/gasoline vehicles running on LPG the benefits are less than expected. The main reason is that dual-fuel vehicles usually start the engine up on gasoline even when LPG is selected as fuel. This cold-start phase is crucial for the quality of the emissions. Moreover, we demonstrate an influence on the chemical composition of emissions of vehicle performance, fuel and the evaporative emission system of the vehicles.

Adam, T. W.; Astorga, C.; Clairotte, M.; Duane, M.; Elsasser, M.; Krasenbrink, A.; Larsen, B. R.; Manfredi, U.; Martini, G.; Montero, L.; Sklorz, M.; Zimmermann, R.; Perujo, A.

2011-06-01

285

Simultaneous film and convection cooling of a plate inserted in the exhaust stream of a gas turbine combustor  

NASA Technical Reports Server (NTRS)

Data were obtained on a parallel-flow film- and convection-cooled test section placed in the exhaust stream of a rectangular-sector combustor. The combustor was operated at atmospheric pressure and at exhaust temperatures of 589 and 1033 K (600 and 1400 F). The cooling air was at ambient pressure and temperature. Test results indicate that it is better to use combined film and convection cooling rather than either film or convection cooling alone for a fixed total coolant flow. An optimum ratio of film to convection cooling flow rates was determined for the particular geometry tested. The experimental results compared well with calculated results.

Marek, C. J.; Juhasz, A. J.

1973-01-01

286

Evaluation of gas removal and bacterial community diversity in a biofilter developed to treat composting exhaust gases  

Microsoft Academic Search

The performance of a new, but simply constructed, biofilter system, developed to purify composting exhaust air, was evaluated. The biofilter was packed with mature compost mixed with activated carbon and sludge sourced from a wastewater treatment plant. An alternating air flow system and a bioaerosol reduction device were designed to prevent pressure drop and reduce bioaerosol release. Experimental results demonstrated

Ying-Chien Chung

2007-01-01

287

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objective of this report period was to continue the development of the Gas Generator design, completion of the hardware and ancillary hardware fabrication and commence the Test Preparations for the testing of the non-polluting unique power turbine driven Gas Generator. Focus during this report period has been on completing the Gas Generator fabrication of hardware and ancillary hardware, and completion of unit closeout brazing and bonding. Because of unacceptable delays encountered in a previously competitively selected test site, CES initiated a re-competition of our testing program and selected an alternate test site. Following that selection, CES used all available resources to make preparations for testing the 10 Mw Gas Generator at the new testing site facilities of NTS at Saugus, CA.

E.W. (Gene) Baxter

2002-06-30

288

FABRICATE AND TEST AN ADVANCED NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

In September 2000 the Department of Energy's National Energy Technology Laboratory (DOE/NETL) contracted with Clean Energy Systems, Inc. (CES) of Sacramento, California to design, fabricate, and test a 20 MW{sub t} (10 MW{sub e}) gas generator. Program goals were to demonstrate a non-polluting gas generator at temperatures up to 3000 F at 1500 psi, and to demonstrate resulting drive gas composition, comprising steam and carbon dioxide substantially free of pollutants. Following hardware design and fabrication, testing, originally planned to begin in the summer of 2001, was delayed by unavailability of the contracted test facility. CES designed, fabricated, and tested the proposed gas generator as originally agreed. The CES process for producing near-zero-emissions power from fossil fuels is based on the near-stoichiometric combustion of a clean gaseous fuel with oxygen in the presence of recycled water, to produce a high-temperature, high-pressure turbine drive fluid comprising steam and carbon dioxide. Tests demonstrated igniter operation over the prescribed ranges of pressure and mixture ratios. Ignition was repeatable and reliable through more than 100 ignitions. Injector design ''A'' was operated successfully at both low power ({approx}20% of rated power) and at rated power ({approx}20 MW{sub t}) in more than 95 tests. The uncooled gas generator configuration (no diluent injectors or cooldown chambers installed) produced drive gases at temperatures approaching 3000 F and at pressures greater than 1550 psia. The fully cooled gas generator configuration, with cooldown chambers and injector ''A'', operated consistently at pressures from 1100 to 1540 psia and produced high pressure, steam-rich turbine drive gases at temperatures ranging from {approx}3000 to as low as 600 F. This report includes description of the intended next steps in the gas generator technology demonstration and traces the anticipated pathway to commercialization for the gas generator technology developed in this program.

Eugene Baxter; Roger E. Anderson; Stephen E. Doyle

2003-06-01

289

The interior concentration distribution of a contaminant gas resulting from the ventilating effect of a jet augmented local exhaust (JALE) booth  

E-print Network

for the investigation. Six conditions involving one exhaust fl ow rate/jet fl ow rate ratio (QE/(}j 6. 63 m3/min/2. 52 m3/min), three jet discharge angles (0', 5', and 10'), and two propane gas flow rates (101. 9 mL/min and 163. 9 mL/min) were examined. Forty... Dual itative Analyses IV. Regression Models . V. Data Collection Sequence. VI. Regression Model: Fourth Degree R-Square VII. Maximum R-Square Procedure Results for Condition 6. 63/2. 52/5/101. 9. VIII. Maximum R-Square Procedure: C(P) Values...

Pazyra, Laurence Paul

2012-06-07

290

CFD Simulation of Gas Pollutant Motion and Dispersion Problem in Wind Tunnel with Respect to Froude Number  

Microsoft Academic Search

Low speed wind tunnels have been used for simulation of wide range of physical problems. One of many possible applications is a simulation of gas pollutant motion and dispersion considering different density of each one. Source term can be defined as a point source, line source or volume source. If modeled geometry with the source is downscaled geometrically and pollutant

Ondrej Zavila

2011-01-01

291

EVALUATION OF A PORTABLE FOURIER TRANSFORM INFRARED GAS ANALYZER FOR MEASUREMENTS OF AIR TOXICS IN POLLUTION PREVENTION RESEARCH  

EPA Science Inventory

A portable Fourier transform infrared gas analyzer with a photoacoustic detector performed reliably during pollution prevention research at two industrial facilities. It exhibited good agreement (within approximately 6%) with other analytical instruments (dispersive infrared and ...

292

Pollutant Exposures from Natural Gas Cooking Burners: A Simulation-Based Assessment for Southern California  

SciTech Connect

Residential natural gas cooking burners (NGCBs) can emit substantial quantities of pollutants and they are typically used without venting. The objective of this study is to quantify pollutant concentrations and occupant exposures resulting from NGCB use in California homes. A mass balance model was applied to estimate time-dependent pollutant concentrations throughout homes and the "exposure concentrations" experienced by individual occupants. The model was applied to estimate nitrogen dioxide (NO{sub 2}), carbon monoxide (CO), and formaldehyde (HCHO) concentrations for one week each in summer and winter for a representative sample of Southern California homes. The model simulated pollutant emissions from NGCBs, NO{sub 2} and CO entry from outdoors, dilution throughout the home, and removal by ventilation and deposition. Residence characteristics and outdoor concentrations of CO and NO{sub 2} were obtained from available databases. Ventilation rates, occupancy patterns, and burner use were inferred from household characteristics. Proximity to the burner(s) and the benefits of using venting range hoods were also explored. Replicate model executions using independently generated sets of stochastic variable values yielded estimated pollutant concentration distributions with geometric means varying less than 10%. The simulation model estimates that in homes using NGCBs without coincident use of venting range hoods, 62%, 9%, and 53% of occupants are routinely exposed to NO{sub 2}, CO, and HCHO levels that exceed acute health-based standards and guidelines. NGCB use increased the sample median of the highest simulated 1-hr indoor concentrations by 100, 3000, and 20 ppb for NO{sub 2}, CO, and HCHO, respectively. Reducing pollutant exposures from NGCBs should be a public health priority. Simulation results suggest that regular use of even moderately effective venting range hoods would dramatically reduce the percentage of homes in which concentrations exceed health-based standards.

Logue, Jennifer M.; Klepeis, Neil E.; Lobscheid, Agnes B.; Singer, Brett C.

2014-06-01

293

Effect of isothermal dilution on emission factors of organic carbon and n-alkanes in the particle and gas phases of diesel exhaust  

NASA Astrophysics Data System (ADS)

To investigate the effect of isothermal dilution (30 °C) on emission factors (EFs) of semivolatile and nonvolatile compounds of heavy-duty diesel exhaust, we measured EFs for particulate matter (PM), organic carbon (OC), and elemental carbon (EC) in the particle phase, and EFs for n-alkanes in both the particle phase and the gas phase of exhaust produced under high-idle engine operating conditions at dilution ratios (DRs) ranging from 8 to 1027. The EC EFs did not vary with DR, whereas the OC EFs in the particle phase determined at DR = 1027 were 13% of the EFs determined at DR = 8, owing to evaporation of organic compounds. Using partitioning theory and n-alkane EFs measured at DR = 14 and 238, we calculated the distributions of compounds between the particle and gas phases at DR = 1760, which corresponds to the DR for tailpipe emissions as they move from the tailpipe to the roadside atmosphere. The gas-phase EF of a compound with a vapor pressure of 10-7 Pa was 0.01 ?g kg-1-fuel at DR = 14, and this value is 1/330 the value derived at DR = 1760. Our results suggest that the EFs of high-volatility compounds in the particle phase will be overestimated and that the EFs of low-volatility compounds in the gas phase will be underestimated if the estimates are derived from data obtained at the low DRs and they are applied to the real world. Therefore, extrapolation from EFs derived at low DR values to EFs at atmospherically relevant DRs will be a source of error in predictions of the concentrations of particulate matter and gas-phase precursors to secondary organic aerosols in air quality models.

Fujitani, Yuji; Saitoh, Katsumi; Fushimi, Akihiro; Takahashi, Katsuyuki; Hasegawa, Shuich; Tanabe, Kiyoshi; Kobayashi, Shinji; Furuyama, Akiko; Hirano, Seishiro; Takami, Akinori

2012-11-01

294

Development of an automated measurement system using a diffusion scrubber and high-performance liquid chromatography for the monitoring of formaldehyde and acetaldehyde in automotive exhaust gas.  

PubMed

An automated measurement system for monitoring formaldehyde (HCHO) and acetaldehyde (CH3CHO) in automotive exhaust gas by using a diffusion scrubber in combination with high-performance liquid chromatography (HPLC) was developed. HCHO and CH3CHO are effectively collected by the diffusion scrubber, which consists of a hydrophobic porous PTFE tube disposed concentrically within a Pyrex-glass tube and a scrubbing solution. 2,4-Dinitrophenylhydrazine is used as the scrubbing solution for trapping HCHO and CH3CHO, which are derivatized to formaldehyde 2,4-dinitrophenylhydrazone (DNPH-HCHO) and acetaldehyde 2,4-dinitrophenylhydrazone (DNPH-CH3CHO), respectively, with phosphoric acid as an acid catalyst. After the collection of the gas sample, the sample solution in the diffusion scrubber is injected into the HPLC system and DNPH-HCHO and DNPH-CH3CHO are separated and determined. All measurement operations are sequenced by a programmable controller and an automated continuous measurement can be performed at 10 min intervals. The collection efficiencies of HCHO and CH3CHO were higher than 97% at a gas flow rate of 0.21 min-1. The detection limit (3 sigma of the blank value) was 0.001 ppm v/v for HCHO and CH3CHO for a 1.61 gas sample volume. No interference of co-existing nitrogen dioxide (NO2) in the collection of HCHO and CH3CHO was observed. The average concentration of HCHO in the exhaust gas from methanol-fueled vehicles was 77.3 ppm v/v (n = 5) in the cold-phase mode when engines were first started. In the hot-phase mode, the average concentration of HCHO was 3.3 ppm v/v (n = 15). The concentrations of HCHO measured by this automated measurement system were in good agreement with those obtained using the impinger-HPLC method. PMID:10396812

Komazaki, Y; Narita, Y; Tanaka, S

1998-11-01

295

Pollutant Exposures from Natural Gas Cooking Burners: A Simulation-Based Assessment for Southern California  

PubMed Central

Background: Residential natural gas cooking burners (NGCBs) can emit substantial quantities of pollutants, and they are typically used without venting range hoods. Objective: We quantified pollutant concentrations and occupant exposures resulting from NGCB use in California homes. Methods: A mass-balance model was applied to estimate time-dependent pollutant concentrations throughout homes in Southern California and the exposure concentrations experienced by individual occupants. We estimated nitrogen dioxide (NO2), carbon monoxide (CO), and formaldehyde (HCHO) concentrations for 1 week each in summer and winter for a representative sample of Southern California homes. The model simulated pollutant emissions from NGCBs as well as NO2 and CO entry from outdoors, dilution throughout the home, and removal by ventilation and deposition. Residence characteristics and outdoor concentrations of NO2 and CO were obtained from available databases. We inferred ventilation rates, occupancy patterns, and burner use from household characteristics. We also explored proximity to the burner(s) and the benefits of using venting range hoods. Replicate model executions using independently generated sets of stochastic variable values yielded estimated pollutant concentration distributions with geometric means varying by < 10%. Results: The simulation model estimated that—in homes using NGCBs without coincident use of venting range hoods—62%, 9%, and 53% of occupants are routinely exposed to NO2, CO, and HCHO levels that exceed acute health-based standards and guidelines. NGCB use increased the sample median of the highest simulated 1-hr indoor concentrations by 100, 3,000, and 20 ppb for NO2, CO, and HCHO, respectively. Conclusions: Reducing pollutant exposures from NGCBs should be a public health priority. Simulation results suggest that regular use of even moderately effective venting range hoods would dramatically reduce the percentage of homes in which concentrations exceed health-based standards. Citation: Logue JM, Klepeis NE, Lobscheid AB, Singer BC. 2014. Pollutant exposures from natural gas cooking burners: a simulation-based assessment for Southern California. Environ Health Perspect 122:43–50;?http://dx.doi.org/10.1289/ehp.1306673 PMID:24192135

Klepeis, Neil E.; Lobscheid, Agnes B.; Singer, Brett C.

2013-01-01

296

Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.  

PubMed

The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns. PMID:21126058

Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C

2011-01-01

297

Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system  

NASA Astrophysics Data System (ADS)

Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi

2011-07-01

298

Sequestration of flue gas CO? by direct gas-solid carbonation of air pollution control system residues.  

PubMed

Direct gas-solid carbonation reactions of residues from an air pollution control system (APCr) were conducted using different combinations of simulated flue gas to study the impact on CO? sequestration. X-ray diffraction analysis of APCr determined the existence of CaClOH, whose maximum theoretical CO? sequestration potential of 58.13 g CO?/kg APCr was calculated by the reference intensity ratio method. The reaction mechanism obeyed a model of a fast kinetics-controlled process followed by a slow product layer diffusion-controlled process. Temperature is the key factor in direct gas-solid carbonation and had a notable influence on both the carbonation conversion and the CO? sequestration rate. The optimal CO? sequestrating temperature of 395 °C was easily obtained for APCr using a continuous heating experiment. CO? content in the flue gas had a definite influence on the CO? sequestration rate of the kinetics-controlled process, but almost no influence on the final carbonation conversion. Typical concentrations of SO? in the flue gas could not only accelerate the carbonation reaction rate of the product layer diffusion-controlled process, but also could improve the final carbonation conversion. Maximum carbonation conversions of between 68.6% and 77.1% were achieved in a typical flue gas. Features of rapid CO? sequestration rate, strong impurities resistance, and high capture conversion for direct gas-solid carbonation were proved in this study, which presents a theoretical foundation for the applied use of this encouraging technology on carbon capture and storage. PMID:23181908

Tian, Sicong; Jiang, Jianguo

2012-12-18

299

Applications of optical measurement technology in pollution gas monitoring at thermal power plants  

NASA Astrophysics Data System (ADS)

This paper presents the work of using advanced optical measurement techniques to implement stack gas emission monitoring and process control. A system is designed to conduct online measurement of SO2/NOX and mercury emission from stacks and slipping NH3 of de-nitrification process. The system is consisted of SO2/NOX monitoring subsystem, mercury monitoring subsystem, and NH3 monitoring subsystem. The SO2/NOX monitoring subsystem is developed based on the ultraviolet differential optical absorption spectroscopy (UV-DOAS) technique. By using this technique, a linearity error less than +/-1% F.S. is achieved, and the measurement errors resulting from optical path contamination and light fluctuation are removed. Moreover, this subsystem employs in situ extraction and hot-wet line sampling technique to significantly reduce SO2 loss due to condensation and protect gas pipeline from corrosion. The mercury monitoring subsystem is used to measure the concentration of element mercury (Hg0), oxidized mercury (Hg2+), and total gaseous mercury (HgT) in the flue gas exhaust. The measurement of Hg with a low detection limit (0.1?g/m3) and a high sensitivity is realized by using cold vapor atom fluorescence spectroscopy (CVAFS) technique. This subsystem is also equipped with an inertial separation type sampling technique to prevent gas pipeline from being clogged and to reduce speciation mercury measurement error. The NH3 monitoring subsystem is developed to measure the concentration of slipping NH3 and then to help improving the efficiency of de-nitrification. The NH3 concentration as low as 0.1ppm is able to be measured by using the off-axis integrated cavity output spectroscopy (ICOS) and the tunable diode laser absorption spectroscopy (TDLAS) techniques. The problem of trace NH3 sampling loss is solved by applying heating the gas pipelines when the measurement is running.

Wang, Jian; Yu, Dahai; Ye, Huajun; Yang, Jianhu; Ke, Liang; Han, Shuanglai; Gu, Haitao; Chen, Yingbin

2011-11-01

300

INCREASED SUSCEPTIBILITY TO INFLUENZA INFECTION AFTER DIESEL EXHAUST EXPOSURE.  

EPA Science Inventory

Inhaled environmental pollutants have a possible role in modulating the susceptibility of humans to respiratory infections. Diesel exhaust (DE) is a major component of urban air pollution and their effects on pulmonary infections is of great concern. Influenza infections cause ...

301

CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME II. APPENDICES A-I  

EPA Science Inventory

The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

302

Synergistic effect of Brønsted acid and platinum on purification of automobile exhaust gases  

PubMed Central

The catalytic purification of automobile exhaust gases (CO, NOx and hydrocarbons) is one of the most practiced conversion processes used to lower the emissions and to reduce the air pollution. Nevertheless, the good performance of exhaust gas purification catalysts often requires the high consumption of noble metals such as platinum. Here we report that the Brønsted acid sites on the external surface of a microporous silicoaluminophosphate (SAPO) act as a promoter for exhaust gas purification, effectively cutting the loading amount of platinum in the catalyst without sacrifice of performance. It is revealed that in the Pt-loaded SAPO-CHA catalyst, there exists a remarkable synergistic effect between the Brønsted acid sites and the Pt nanoparticles, the former helping to adsorb and activate the hydrocarbon molecules for NO reduction during the catalytic process. The thermal stability of SAPO-CHA also makes the composite catalyst stable and reusable without activity decay. PMID:23907148

Fu, Wei; Li, Xin-Hao; Bao, Hong-Liang; Wang, Kai-Xue; Wei, Xiao; Cai, Yi-Yu; Chen, Jie-Sheng

2013-01-01

303

Fate of hazardous air pollutants in oxygen-fired coal combustion with different flue gas recycling.  

PubMed

Experiments were performed to characterize transformation and speciation of hazardous air pollutants (HAPs), including SO(2)/SO(3), NO(x), HCl, particulate matter, mercury, and other trace elements in oxygen-firing bituminous coal with recirculation flue gas (RFG) from 1) an electrostatic precipitator outlet or 2) a wet scrubber outlet. The experimental results showed that oxycombustion with RFG generated a flue gas with less volume and containing HAPs at higher levels, while the actual emissions of HAPs per unit of energy produced were much less than that of air-blown combustion. NO(x) reduction was achieved in oxycombustion because of the elimination of nitrogen and the destruction of NO in the RFG. The elevated SO(2)/SO(3) in flue gas improved sulfur self-retention. SO(3) vapor could reach its dew point in the flue gas with high moisture, which limits the amount of SO(3) vapor in flue gas and possibly induces material corrosion. Most nonvolatile trace elements were less enriched in fly ash in oxycombustion than air-firing because of lower oxycombustion temperatures occurring in the present study. Meanwhile, Hg and Se were found to be enriched on submicrometer fly ash at higher levels in oxy-firing than in air-blown combustion. PMID:22439940

Zhuang, Ye; Pavlish, John H

2012-04-17

304

Anti-air pollution & energy conservation system for automobiles using leaded or unleaded gasoline, diesel or alternate fuel  

DOEpatents

Exhaust gases from an internal combustion engine operating with leaded or unleaded gasoline or diesel or natural gas, are used for energizing a high-speed gas turbine. The convoluting gas discharge causes a first separation stage by stratifying of heavier and lighter exhaust gas components that exit from the turbine in opposite directions, the heavier components having a second stratifying separation in a vortex tube to separate combustible pollutants from non-combustible components. The non-combustible components exit a vortex tube open end to atmosphere. The lighter combustible, pollutants effected in the first separation are bubbled through a sodium hydroxide solution for dissolving the nitric oxide, formaldehyde impurities in this gas stream before being piped to the engine air intake for re-combustion, thereby reducing the engine's exhaust pollution and improving its fuel economy. The combustible, heavier pollutants from the second separation stage are piped to air filter assemblies. This gas stream convoluting at a high-speed through the top stator-vanes of the air filters, centrifugally separates the coalescent water, aldehydes, nitrogen dioxides, sulfates, sulfur, lead particles which collect at the bottom of the bowl, wherein it is periodically released to the roadway. Whereas, the heavier hydrocarbon, carbon particles are piped through the air filter's porous element to the engine air intake for re-combustion, further reducing the engine's exhaust pollution and improving its fuel economy.

Bose, Ranendra K. (14346 Jacob La., Centreville, VA 20120-3305)

2002-06-04

305

40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.  

Code of Federal Regulations, 2011 CFR

...sampling system; Otto-cycle and non-petroleum-fueled engines. 86.1309-90...sampling system; Otto-cycle and non-petroleum-fueled engines. (a)(1) General...gasoline-fueled, natural gas-fueled, liquefied petroleum gas-fueled or...

2011-07-01

306

40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.  

Code of Federal Regulations, 2013 CFR

...sampling system; Otto-cycle and non-petroleum-fueled engines. 86.1309-90...sampling system; Otto-cycle and non-petroleum-fueled engines. (a)(1) General...gasoline-fueled, natural gas-fueled, liquefied petroleum gas-fueled or...

2013-07-01

307

40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.  

Code of Federal Regulations, 2012 CFR

...sampling system; Otto-cycle and non-petroleum-fueled engines. 86.1309-90...sampling system; Otto-cycle and non-petroleum-fueled engines. (a)(1) General...gasoline-fueled, natural gas-fueled, liquefied petroleum gas-fueled or...

2012-07-01

308

METHODOLOGIES FOR QUANTIFYING POLLUTION PREVENTION BENEFITS FROM LANDFILL GAS CONTROL AND UTILIZATION  

EPA Science Inventory

The report describes developing emission factors for controlled primary pollutants (e.g., nonmethane organic compounds) and secondary air pollutants (e.g., carbon monoxide). The report addresses the following criteria air pollutants and greenhouse gases: carbon dioxide, carbon mo...

309

Local aspects of vehicular pollution  

NASA Astrophysics Data System (ADS)

We consider the local aspects of vehicular pollution by the use of l:10 scale models. The model automobiles were placed in a low-velocity wind tunnel to simulate a queue of slow-moving city traffic and tracer gasses were then injected into the air flow though the tail pipes fitted to two of the models. Measurements show that the exhaust gases are entrained in the wake of the vehicle from which they were emitted, and are dispersed mainly by the passage of the following car. The spatial distribution of tracer gas along and across the models suggests that the level of pollution received by a commuter in a slow-moving heavy traffic may be strongly influenced by the pollution produced from the car immediately in front.

Clifford, M. J.; Clarke, R.; Riffat, S. B.

310

40 CFR 600.112-08 - Exhaust sample analysis.  

Code of Federal Regulations, 2014 CFR

...Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy and Carbon-Related Exhaust Emission Test Procedures § 600.112-08...

2014-07-01

311

Measurement comparison of gas phase pollutants during field campaign in Pearl River Delta, China  

NASA Astrophysics Data System (ADS)

Pearl River delta, an economically developed region in Guangdong province China, has been suffering from serious ground-level ozone pollution. To understand the formation mechanisms of the photochemical smog in this area, a field measurement campaign involving 12 separate institutes, was performed from Oct. 1 to Nov. 4, 2004. Measurements of gas phase pollutants, performed by the different research groups using several different methods, were inter-compared. Ambient SO2, O3 and NO were measured by Peking University and Hong Kong Polytechnic University using the same methods: chemiluminescence for NOx, pulsed fluorescence for SO2, and UV photometric method for O3. VOC speciation was accomplished using canister sampling followed by GC-MS measurement by Peking University and on-line GC-FID technology by National Central University in Taiwan. Ambient concentrations of HONO, the photolysis of which is the most important source of OH radical in Pearl River delta, was measured by two wet chemical methods: one from Energy Research Foundation of the Netherlands and one developed in Peking University. Based on these inter-comparisons, the co-variation of O3, NO and VOCs at an urban site and one rural site in Pearl River delta and estimates of the relative contributions to OH production from photolysis of O3, HONO and HCHO will be presented.

Shao, M.; Zeng, L.; Hu, M.; Zhang, Y.

2005-12-01

312

Reduction of gaseous pollutant emissions from gas turbine combustors using hydrogen-enriched jet fuel  

NASA Technical Reports Server (NTRS)

Recent progress in an evaluation of the applicability of the hydrogen enrichment concept to achieve ultralow gaseous pollutant emission from gas turbine combustion systems is described. The target emission indexes for the program are 1.0 for oxides of nitrogen and carbon monoxide, and 0.5 for unburned hydrocarbons. The basic concept utilizes premixed molecular hydrogen, conventional jet fuel, and air to depress the lean flammability limit of the mixed fuel. This is shown to permit very lean combustion with its low NOx production while simulataneously providing an increased flame stability margin with which to maintain low CO and HC emission. Experimental emission characteristics and selected analytical results are presented for a cylindrical research combustor designed for operation with inlet-air state conditions typical for a 30:1 compression ratio, high bypass ratio, turbofan commercial engine.

Clayton, R. M.

1976-01-01

313

Detection of gas phase combustion products and pollutants via intra-cavity Raman spectroscopy  

SciTech Connect

An intra-cavity Raman spectrometer was employed in the detection of various gas phase pollutants and combustion products. Using the spectrometer, data were collected for sulfur dioxide, nitric oxide, nitrogen dioxide, carbon monoxide, carbon dioxide, oxygen, and total hydrocarbons in both noncombustion and combustion environments. Based on the data collected, instrument detection limits were established and calibration curves were constructed. It was found that the intra-cavity Raman system produced a linear calibration curve for sulfur dioxide, nitrogen dioxide, and carbon monoxide in a noncombustion environment, and had a linear response for sulfur dioxide and carbon monoxide during combustion. Various combustion scenarios were also set up to establish combustion efficiency of a lab scale burner system based on oxygen, carbon monoxide, carbon dioxide, and hydrocarbon data.

Underhill-Shanks, K.S.; Hudson, M.K. [Univ. of Arkansas, Little Rock, AR (United States)

1995-12-01

314

Chemical Pollution from Transportation Vehicles  

PubMed Central

Recent publicity on electrically powered vehicles notwithstanding, the gasoline engine will probably be the principal power plant for passenger cars for at least the next decade. Chemical pollutants discharged by the gasoline engine are now under partial control. Motor cars of 1968 and 1969 model discharge only about 30 percent as much carbon monoxide and unburned hydrocarbons as do older models. In theory, carbon monoxide, unburned hydrocarbons and oxides of nitrogen ultimately can be completely removed from gasoline engine exhaust. In order to accomplish this it would be necessary to modify cars to operate satisfactorily on a lean mixture and perhaps to use a catalyst in the exhaust system. Present designs of gas turbines for aircraft and for future projected application to ground vehicles yield pollutants (except for smoke) at levels below those of gasoline engines for a decade to come. It has also been shown possible to eliminate smoke as well as odor from the gas turbine. Thus with proper effort it is feasible to reduce pollution of the atmosphere due to transportation to an acceptable level, even if electrically or alternatively powered vehicles cannot be developed for a decade. PMID:4183827

Starkman, Ernest S.

1969-01-01

315

Seasonal characteristics of gas-phase air pollutants: implications for public health in northeastern New Jersey  

NASA Astrophysics Data System (ADS)

To characterize the impact of urban air pollution and local weather conditions on human health, the ambient air concentrations of nitrogen oxide (NOx) and ground-level ozone (O3) were measured at the Meadowlands in Lyndhurst, NJ (41N, 74W) from June 1, 2007 to May 31, 2008. Meteorological data, mainly temperature, wind speed, relative humidity and barometric pressure, were supplemented with data from Weather Underground. Public health data were obtained from the New Jersey Department of Health and Senior Services (NJDHSS). The relationship between gas-phase pollutants and hospital admissions were examined through path analytic models by using multiple regressions and bivariate correlations. The meteorological conditions and air pollutants that may be associated with human respiratory health effects are analyzed. Preliminary results demonstrate that the ambient levels of NOx and O3 are influenced by certain meteorological conditions in the Meadowlands, and that there is a strong relationship between hospital admission and personal exposure to NO2 over the short-term. There is no direct relationship between O3 and hospital admission (r=-0.092), whereas hospital admission and NOx correlate (r=0.317) but more significantly with NO2 (r=.359) at a significance level of 0.01. Hospital admission rates are indirectly affected by humidity (r=-0.077). The seasonal dependence of pollutants is caused mainly by low wind speed and differences in chemical processing, making them interdependent. The monthly average O3 ranged from 11.1ppb to 36.2ppb with the highest values in summer; NOx ranged from 17.0ppb to 29.0ppb with no marked seasonal variations and were lower on weekends than on week days. There were dissimilar diurnal patterns and an inverse relationship between the hourly average of NOx and O3 concentrations, suggesting that O3 formation was not limited by the availability of NOx but is likely influenced by a VOC-sensitive chemical regime. This study provides a basis for the need of developing additional plans for protection against respiratory illnesses and for setting improved air quality standards in this region.

Roberts-Semple, D. A.; Gao, Y.

2011-12-01

316

Greenhouse gas emission and groundwater pollution potential of soils amended with raw swine manure, dry and wet pyrolyzed swine biochars  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this research is to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with raw swine solid and swine biochars made from different thermochemical conditions. Triplicate sets of small pots were designed: 1) control soil with a 50/50 mixture of...

317

Water pollution risk associated with natural gas extraction from the Marcellus Shale.  

PubMed

In recent years, shale gas formations have become economically viable through the use of horizontal drilling and hydraulic fracturing. These techniques carry potential environmental risk due to their high water use and substantial risk for water pollution. Using probability bounds analysis, we assessed the likelihood of water contamination from natural gas extraction in the Marcellus Shale. Probability bounds analysis is well suited when data are sparse and parameters highly uncertain. The study model identified five pathways of water contamination: transportation spills, well casing leaks, leaks through fractured rock, drilling site discharge, and wastewater disposal. Probability boxes were generated for each pathway. The potential contamination risk and epistemic uncertainty associated with hydraulic fracturing wastewater disposal was several orders of magnitude larger than the other pathways. Even in a best-case scenario, it was very likely that an individual well would release at least 200 m³ of contaminated fluids. Because the total number of wells in the Marcellus Shale region could range into the tens of thousands, this substantial potential risk suggested that additional steps be taken to reduce the potential for contaminated fluid leaks. To reduce the considerable epistemic uncertainty, more data should be collected on the ability of industrial and municipal wastewater treatment facilities to remove contaminants from used hydraulic fracturing fluid. PMID:22211399

Rozell, Daniel J; Reaven, Sheldon J

2012-08-01

318

Continuous-wave terahertz by photomixing: applications to gas phase pollutant detection and quantification  

NASA Astrophysics Data System (ADS)

Recent advances in the development of monochromatic continuous-wave terahertz sources suitable for high resolution gas phase spectroscopy and pollution monitoring are reviewed. Details of a source using an ultra fast opto-electronic photomixing element are presented. The construction of a terahertz spectrometer using this source has allowed spectroscopic characterisation and application studies to be completed. Analysis of H 2S and OCS under laboratory conditions are used to demonstrate the spectrometer performance, and the determination of the transition line strengths and pressure self broadening coefficients for pure rotational transitions of OCS. The spectral purity 5 MHz, tunability 0.3 to 3 THz, and long wavelength ?200 ?m of this source have been exploited to identify and quantify numerous chemical species in cigarette smoke. The key advantages of this frequency domain are its high species selectivity and the possibility to make reliable measurements of gas phase samples heavily contaminated by aerosols and particles. To cite this article: F. Hindle et al., C. R. Physique 9 (2008).

Hindle, Francis; Cuisset, Arnaud; Bocquet, Robin; Mouret, Gaël

2008-03-01

319

Observations of gas phase hydrochloric acid in the polluted marine boundary layer  

NASA Astrophysics Data System (ADS)

measurements of gas phase hydrochloric acid (HCl), particulate chloride (pCl-), and reactive nitrogen oxides (NOy) were made in the polluted marine boundary layer along the California coastline during spring 2010. These observations are used to assess both the rate of Cl atom production from HCl and the role of direct HCl emissions and subsequent partitioning as a source for pCl-. Observations of HCl made in coastal Southern California are broadly correlated with NOz (NOz ? NOy - NOx), peaking at 11 A.M. The observed median HCl mixing ratio in Southern California is 1.3 ppb (interquartile range: 0.53-2.7 ppb), as compared to 0.19 ppb (interquartile range: 0.10-0.38 ppb) measured along the Sacramento River between San Francisco and Sacramento. Concurrent measurements of aerosol ion chemistry indicate that aerosol particles sampled in Northern California are heavily depleted in Cl-, corresponding to a mean pCl- deficit of 0.05 ± 0.03 (1?) ppb for sub-10 µm aerosol particles. In comparison, aerosols measured in Southern California indicate that over 25% of particles showed an addition of Cl- to the particle population. Observations presented here suggest that primary sources of HCl, or gas phase chlorine precursors to HCl, are likely underestimated in the California Air Resource Board emissions inventory. These results highlight the need for future field observations designed to better constrain direct reactive halogen emissions.

Crisp, Timia A.; Lerner, Brian M.; Williams, Eric J.; Quinn, Patricia K.; Bates, Timothy S.; Bertram, Timothy H.

2014-06-01

320

Fast automotive diesel exhaust measurement using quantum cascade lasers  

NASA Astrophysics Data System (ADS)

Step by step, US and European legislations enforce the further reduction of atmospheric pollution caused by automotive exhaust emissions. This is pushing automotive development worldwide. Fuel efficient diesel engines with SCRtechnology can impede NO2-emission by reduction with NH3 down to the ppm range. To meet the very low emission limits of the Euro6 resp. US NLEV (National Low Emission Vehicle) regulations, automotive manufacturers have to optimize continuously all phases of engine operation and corresponding catalytic converters. Especially nonstationary operation holds a high potential for optimizing gasoline consumption and further reducing of pollutant emissions. Test equipment has to cope with demanding sensitivity and speed requirements. In the past Fraunhofer IPM has developed a fast emission analyzer called DEGAS (Dynamic Exhaust Gas Analyzer System), based on cryogenically cooled lead salt lasers. These systems have been used at Volkswagen AG`s test benches for a decade. Recently, IPM has developed DEGAS-Next which is based on cw quantum cascade lasers and thermoelectrically cooled detectors. The system is capable to measure three gas components (i.e. NO, NO2, NH3) in two channels with a time resolution of 20 ms and 1 ppm detection limits. We shall present test data and a comparison with fast FTIR measurements.

Herbst, J.; Brunner, R.; Lambrecht, A.

2013-12-01

321

The Baryon Cycle of Dwarf Galaxies: Dark, Bursty, Gas-rich Polluters  

NASA Astrophysics Data System (ADS)

We present results from a fully cosmological, very high-resolution, ?CDM simulation of a group of seven field dwarf galaxies with present-day virial masses in the range M vir = 4.4 × 108-3.6 × 1010 M ?. The simulation includes a blastwave scheme for supernova feedback, a star-formation recipe based on a high gas density threshold, metal-dependent radiative cooling, a scheme for the turbulent diffusion of metals and thermal energy, and a uniform UV background. The properties of the simulated dwarfs are strongly modulated by the depth of the gravitational potential well. All three halos with M vir < 109 M ? are devoid of stars, as they never reach the density threshold for star formation of 100 atoms cm-3. The other four, M vir > 109 M ? dwarfs have blue colors, low star-formation efficiencies, high cold gas-to-stellar mass ratios, and low stellar metallicities. Their bursty star-formation histories are characterized by peak specific star-formation rates in excess of 50-100 Gyr-1, far outside the realm of normal, more massive galaxies. The median stellar age of the simulated galaxies decreases with decreasing halo mass, with the two M vir ~= 2-3 × 109 M ? dwarfs being predominantly young, and the two more massive systems hosting intermediate and older populations. The cosmologically young dwarfs are lit up by tidal interactions, have compact morphologies, and have metallicities and cold gas fractions similar to the relatively quiescent, extremely metal-deficient dwarf population. Metal-enriched galactic outflows produce sub-solar effective yields and pollute with heavy elements a megaparsec-size region of the intergalactic medium, but are not sufficient to completely quench star-formation activity and are absent in the faintest dwarfs.

Shen, Sijing; Madau, Piero; Conroy, Charlie; Governato, Fabio; Mayer, Lucio

2014-09-01

322

40 CFR 1065.655 - Chemical balances of fuel, intake air, and exhaust.  

Code of Federal Regulations, 2013 CFR

...Chemical balances of fuel, intake air, and exhaust. 1065.655 Section...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Chemical balances of fuel, intake air, and exhaust. (a)...

2013-07-01

323

40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Dilution air and diluted exhaust flow meters...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Measurements § 1065.240 Dilution air and diluted exhaust flow...

2014-07-01

324

40 CFR 1065.655 - Chemical balances of fuel, intake air, and exhaust.  

Code of Federal Regulations, 2011 CFR

...Chemical balances of fuel, intake air, and exhaust. 1065.655 Section...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Chemical balances of fuel, intake air, and exhaust. (a)...

2011-07-01

325

40 CFR 1065.655 - Chemical balances of fuel, intake air, and exhaust.  

Code of Federal Regulations, 2014 CFR

...Chemical balances of fuel, intake air, and exhaust. 1065.655 Section...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Chemical balances of fuel, intake air, and exhaust. (a)...

2014-07-01

326

40 CFR 1065.655 - Chemical balances of fuel, intake air, and exhaust.  

Code of Federal Regulations, 2010 CFR

...Chemical balances of fuel, intake air, and exhaust. 1065.655 Section...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Chemical balances of fuel, intake air, and exhaust. (a)...

2010-07-01

327

40 CFR 1065.655 - Chemical balances of fuel, intake air, and exhaust.  

Code of Federal Regulations, 2012 CFR

...Chemical balances of fuel, intake air, and exhaust. 1065.655 Section...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES...Chemical balances of fuel, intake air, and exhaust. (a)...

2012-07-01

328

Air pollution: Remote sensing. (Latest citations from the Aerospace database). Published Search  

SciTech Connect

The bibliography contains citations concerning the application of remote sensing to air pollution detection. Remote sensing techniques discussed include radar scattering, aerial and spaceborne photography, microwave radiometry, and thermal imaging. Applications include the monitoring of stack gas emissions, vegetation emissions, forest fires, episodic air pollution, exhaust emissions, chlorohydrocarbons, urban smog, and general aspects of air pollution monitoring and identification. Remote sensing techniques applied to ocean pollution are discussed in a separate bibliography. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-09-01

329

Multiresidue analysis of pollutants as their trimethylsilyl derivatives, by gas chromatography-mass spectrometry.  

PubMed

This paper reports a multiresidue analysis procedure which permits the identification and quantification of sixty-three water-soluble pollutants. Subsequent to their solid-phase extraction (SPE) enrichment, analyses of species have been carried out from one solution, by a single injection, as their trimethylsilyl-oxime ether/ester derivatives, by gas chromatography-mass spectrometry, within 31min. Based on our optimized extraction, derivatization and mass fragmentation studies separation have been performed in the total ion current mode, identification and quantification of compounds have been carried out on the basis of their selective fragment ions. Including various pharmaceuticals, benzoic acid, its substituted species, different aromatic carboxylic acids, cholic acids, unsaturated and saturated fatty acids, aliphatic dicarboxylic acids, as well as synthetic pollutants of various origins (2,4-di-tert-butylphenol, different phthalates). Standard compounds were added to 500 mL effluent wastewater samples, at three concentrations (1-5 microg/L, 5-10 microg/L and 10-20 microg/L). Recoveries, using the Waters Oasis cartridges performing extractions at pH 2, pH 4 and pH 7 proved to be the optimum at pH 4 (average recoveries (94.5%), except for cholesterol (10%), paracetamol (18%) and 2,5-dihydroxybenzoic acid (25%). Carbamazepine could be recovered at pH 7, only. Responses, obtained with derivatized standards proved to be linear in the range of 4-80 microg/L levels. Limit of quantitation values varied between 0.92 ng/L (4-hydroxyphenylacetic acid) and 600 ng/L (dehydrocholic acid) concentrations. One of the most important messages of this work is the confirmation of the origin of blank values. It was shown that contaminants, mainly 2,4-di-tert-butylphenol, different phthalates and fatty acids, are sourced both from the reagents and mainly from the SPE procedure, independent on the cartridge applied. Reproducibilities, characterized with the relative standard deviations (RSDs) of measurements, varied between 0.71% and 10%, with an average of 4.38% RSD. The practical utility of the method was shown by the identification and quantification of the pollutant contents of Hungarian influent and effluent wastewaters (for six consecutive months and that of the Danube River for 2 months). PMID:19201001

Sebok, A; Vasanits-Zsigrai, A; Helenkár, A; Záray, Gy; Molnár-Perl, I

2009-03-20

330

Apparatus for recovering heat from exhaust gases of marine prime movers  

Microsoft Academic Search

Apparatus for recovering heat from the exhaust gases of marine prime movers is described comprising a feed water line and an exhaust gas economizer for effecting heat exchange between the exhaust gases discharged from the prime mover and feed water supplied from a feed water tank; said exhaust gas economizer having a high pressure steam generator section for receiving high

K. Nagashima; T. Yamada

1980-01-01

331

Catalyst arrangement for the exhaust system of an internal combustion engine  

Microsoft Academic Search

This patent describes a catalyst arrangement for the exhaust system of an internal combustion engine having an exhaust conduit carrying hot exhaust gas flow from the engine and a particulate trap interposed in the exhaust gas flow. The arrangement comprises: (i) a body of solid material incorporating a substance having catalytic properties and other materials effective to promote a low

Bostock

1987-01-01

332

40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...  

Code of Federal Regulations, 2012 CFR

...complete mixing of the exhaust and dilution air between the mixing orifice and each of the two sample probes (i.e., the particulate...complete mixing of the exhaust and dilution air between the mixing orifice and the particulate sample probe. It is recommended that...

2012-07-01

333

40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...  

Code of Federal Regulations, 2013 CFR

...complete mixing of the exhaust and dilution air between the mixing orifice and each of the two sample probes (i.e., the particulate...complete mixing of the exhaust and dilution air between the mixing orifice and the particulate sample probe. It is recommended that...

2013-07-01

334

40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...  

Code of Federal Regulations, 2014 CFR

...complete mixing of the exhaust and dilution air between the mixing orifice and each of the two sample probes (i.e., the particulate...complete mixing of the exhaust and dilution air between the mixing orifice and the particulate sample probe. It is recommended that...

2014-07-01

335

Improving the accuracy of vehicle emissions profiles for urban transportation greenhouse gas and air pollution inventories.  

PubMed

Metropolitan greenhouse gas and air emissions inventories can better account for the variability in vehicle movement, fleet composition, and infrastructure that exists within and between regions, to develop more accurate information for environmental goals. With emerging access to high quality data, new methods are needed for informing transportation emissions assessment practitioners of the relevant vehicle and infrastructure characteristics that should be prioritized in modeling to improve the accuracy of inventories. The sensitivity of light and heavy-duty vehicle greenhouse gas (GHG) and conventional air pollutant (CAP) emissions to speed, weight, age, and roadway gradient are examined with second-by-second velocity profiles on freeway and arterial roads under free-flow and congestion scenarios. By creating upper and lower bounds for each factor, the potential variability which could exist in transportation emissions assessments is estimated. When comparing the effects of changes in these characteristics across U.S. cities against average characteristics of the U.S. fleet and infrastructure, significant variability in emissions is found to exist. GHGs from light-duty vehicles could vary by -2%-11% and CAP by -47%-228% when compared to the baseline. For heavy-duty vehicles, the variability is -21%-55% and -32%-174%, respectively. The results show that cities should more aggressively pursue the integration of emerging big data into regional transportation emissions modeling, and the integration of these data is likely to impact GHG and CAP inventories and how aggressively policies should be implemented to meet reductions. A web-tool is developed to aide cities in improving emissions uncertainty. PMID:25438089

Reyna, Janet L; Chester, Mikhail V; Ahn, Soyoung; Fraser, Andrew M

2015-01-01

336

30 CFR 36.25 - Engine exhaust system.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Engine exhaust system. 36.25 ...FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION... § 36.25 Engine exhaust system. (a) Construction...or discharge of heated particles to a surrounding flammable...positioned that only cooled exhaust gas will...

2010-07-01

337

30 CFR 36.25 - Engine exhaust system.  

Code of Federal Regulations, 2011 CFR

...exhaust system of the engine shall be provided...exhaust system, and the material of construction shall...the fuel supply to the engine at a safe minimum water...shall be constructed of material, satisfactory to MSHA...shall be provided for the engine exhaust gas. The...

2011-07-01

338

30 CFR 36.25 - Engine exhaust system.  

Code of Federal Regulations, 2013 CFR

...exhaust system of the engine shall be provided...exhaust system, and the material of construction shall...the fuel supply to the engine at a safe minimum water...shall be constructed of material, satisfactory to MSHA...shall be provided for the engine exhaust gas. The...

2013-07-01

339

30 CFR 36.25 - Engine exhaust system.  

Code of Federal Regulations, 2012 CFR

...exhaust system of the engine shall be provided...exhaust system, and the material of construction shall...the fuel supply to the engine at a safe minimum water...shall be constructed of material, satisfactory to MSHA...shall be provided for the engine exhaust gas. The...

2012-07-01

340

Modeling Population Exposures to Pollutants Emitted from Natural Gas Cooking Burners  

SciTech Connect

We developed a physics-based data-supported model to investigate indoor pollutant exposure distributions resulting from use of natural gas cooking appliances across households in California. The model was applied to calculate time-resolved indoor concentrations of CO, NO2 and formaldehyde resulting from cooking burners and entry with outdoor air. Exposure metrics include 1-week average concentrations and frequency of exceeding ambient air quality standards. We present model results for Southern California (SoCal) using two air-exchange scenarios in winter: (1) infiltration-only, and (2) air exchange rate (AER) sampled from lognormal distributions derived from measurements. In roughly 40percent of homes in the SoCal cohort (N=6634) the 1-hour USEPA NO2 standard (190 ?g/m3) was exceeded at least once. The frequency of exceeding this standard was largely independent of AER assumption, and related primarily to building volume, emission rate and amount of burner use. As expected, AER had a more substantial impact on one-week average concentrations.

Lobscheid, Agnes; Singer, Brett C.; Klepeis, Neil E.

2011-06-01

341

Quantification of toxic hydrocarbon target compounds in engine exhaust and air by aluminum oxide porous-layer open-tubular capillary gas chromatography-mass spectrometry using isotopically labeled internal standards  

Microsoft Academic Search

A method for the determination of 1,3-butadiene, benzene and toluene in ambient air and engine exhaust is described. Air was sampled with a canister and then analysed by Al2O3-coated porous-layer open-tubular (PLOT) capillary gas chromatography-mass spectrometry. The PLOT column provides better resolution for light hydrocarbons and also alleviates the need of using a sub-ambient oven temperature. While the retention times

Cheng-Chiech Huang; Yunn-Chyi Chen; Guor-Rong Her; Chang-Chuan Chan

1996-01-01

342

Argon/UF6 plasma exhaust gas reconstitution experiments using preheated fluorine and on-line diagnostics. [fissioning uranium plasma core reactor design  

NASA Technical Reports Server (NTRS)

The feasibility of employing a flowing, high-temperature, pure fluorine/UF6 regeneration system to efficiently convert a large fraction of the effluent plasma exhaust back to pure UF6 was demonstrated. The custom built T.O.F. mass spectrometer sampling system permitted on-line measurements of the UF6 concentration at different locations in the exhaust system. Negligible amounts ( 100 ppm) of UF6 were detected in the axial bypass exhaust duct and the exhaust ducts downstream of the cryogenic trap system used to collect the UF6, thus verifying the overall system efficiency over a range of operating conditions. Use of a porous Monel duct as part of the exhaust duct system, including provision for injection of pure fluorine, provided a viable technique to eliminate uranium compound residue on the inside surface of the exhaust ducts. Typical uranium compound mass deposition per unit area of duct was 2 micron g/sq cm. This porous duct technique is directly applicable to future uranium compound transfer exhaust systems. Throughout these experiments, additional basic data on the corrosion aspects of hot, pressurized UF6/fluorine were also accumulated.

Roman, W. C.

1979-01-01

343

Measurement of atmospheric pollutants associated with oil and natural gas exploration and production activity in Pennsylvania's Allegheny National Forest.  

PubMed

Oil and natural gas exploration and production (E&P) activities generate emissions from diesel engines, compressor stations, condensate tanks, leaks and venting of natural gas, construction of well pads, and well access roads that can negatively impact air quality on both local and regional scales. A mobile, autonomous air quality monitoring laboratory was constructed to collect measurements of ambient concentrations of pollutants associated with oil and natural gas E&P activities. This air-monitoring laboratory was deployed to the Allegheny National Forest (ANF) in northwestern Pennsylvania for a campaign that resulted in the collection of approximately 7 months of data split between three monitoring locations between July 2010 and June 2011. The three monitoring locations were the Kane Experimental Forest (KEF) area in Elk County, which is downwind of the Sackett oilfield; the Bradford Ranger Station (BRS) in McKean County, which is downwind of a large area of historic oil and gas productivity; and the U.S. Forest Service Hearts Content campground (HC) in Warren County, which is in an area relatively unimpacted by oil and gas development and which therefore yielded background pollutant concentrations in the ANF. Concentrations of criteria pollutants ozone and NO2 did not vary significantly from site to site; averages were below National Ambient Air Quality Standards. Concentrations of volatile organic compounds (VOCs) associated with oil and natural gas (ethane, propane, butane, pentane) were highly correlated. Applying the conditional probability function (CPF) to the ethane data yielded most probable directions of the sources that were coincident with known location of existing wells and activity. Differences between the two impacted and one background site were difficult to discern, suggesting the that the monitoring laboratory was a great enough distance downwind of active areas to allow for sufficient dispersion with background air such that the localized plumes were not detected. Implications: Monitoring of pollutants associated with oil and natural gas exploration and production activity at three sites within the Allegheny National Forest (ANF) showed only slight site-to-site differences even with one site far removed from these activities. However, the impact was evident not in detection of localized plumes but in regional elevated ethane concentrations, as ethane can be considered a tracer species for oil and natural gas activity. The data presented serve as baseline conditions for evaluation of impacts from future development of Marcellus or Utica shale gas reserves. PMID:25283004

Pekney, Natalie J; Veloski, Garret; Reeder, Matthew; Tamilia, Joseph; Rupp, Erik; Wetzel, Alan

2014-09-01

344

77 FR 9303 - National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric...  

Federal Register 2010, 2011, 2012, 2013, 2014

...HAP emissions from EGUs are below the detection levels of the EPA test methods, even...beta attenuation, or mass accumulation detection of the exhaust gas or representative...emissions of these pollutants are below the detection levels of EPA test methods and,...

2012-02-16

345

DIESEL EXHAUST ENHANCES INFLUENZA VIRUS INFECTIONS IN RESPIRATORY EPITHELIAL CELLS  

EPA Science Inventory

Several factors, such as age and nutritional status can affect the susceptibility to influenza infections. Moreover, exposure to air pollutants, such as diesel exhaust (DE), has been shown to affect respiratory virus infections in rodent models. Influenza virus primarily infects ...

346

Variable area exhaust nozzle  

NASA Technical Reports Server (NTRS)

An exhaust nozzle for a gas turbine engine comprises a number of arcuate flaps pivotally connected to the trailing edge of a cylindrical casing which houses the engine. Seals disposed within the flaps are spring biased and extensible beyond the side edges of the flaps. The seals of adjacent flaps are maintained in sealing engagement with each other when the flaps are adjusted between positions defining minimum nozzle flow area and the cruise position. Extensible, spring biased seals are also disposed within the flaps adjacent to a supporting pylon to thereby engage the pylon in a sealing arrangement. The flaps are hinged to the casing at the central portion of the flaps' leading edges and are connected to actuators at opposed outer portions of the leading edges to thereby maximize the mechanical advantage in the actuation of the flaps.

Johnston, E. A. (inventor)

1979-01-01

347

The National Environmental Respiratory Center (NERC) experiment in multi-pollutant air quality health research: III. Components of diesel and gasoline engine exhausts, hardwood smoke and simulated downwind coal emissions driving non-cancer biological responses in rodents.  

PubMed

An approach to identify causal components of complex air pollution mixtures was explored. Rats and mice were exposed by inhalation 6?h daily for 1 week or 6 months to dilutions of simulated downwind coal emissions, diesel and gasoline exhausts and wood smoke. Organ weights, hematology, serum chemistry, bronchoalveolar lavage, central vascular and respiratory allergic responses were measured. Multiple additive regression tree (MART) analysis of the combined database ranked 45 exposure (predictor) variables for importance to models best fitting 47 significant responses. Single-predictor concentration-response data were examined for evidence of single response functions across all exposure groups. Replication of the responses by the combined influences of the two most important predictors was tested. Statistical power was limited by inclusion of only four mixtures, albeit in multiple concentrations each and with particles removed for some groups. Results gave suggestive or strong evidence of causation of 19 of the 47 responses. The top two predictors of the 19 responses included only 12 organic and 6 inorganic species or classes. An increase in red blood cell count of rats by ammonia and pro-atherosclerotic vascular responses of mice by inorganic gases yielded the strongest evidence for causation and the best opportunity for confirmation. The former was a novel finding; the latter was consistent with other results. The results demonstrated the plausibility of identifying putative causal components of highly complex mixtures, given a database in which the ratios of the components are varied sufficiently and exposures and response measurements are conducted using a consistent protocol. PMID:25162720

Mauderly, Joe L; Seilkop, Steven K

2014-09-01

348

On-site monitoring of volatile organic compounds as hazardous air pollutants by gas chromatography  

Microsoft Academic Search

There are a large number of organic components in air. These components can be classified in six groups. On-site monitoring procedures for two of these groups, oxidant precursors and hazardous air pollutants, are reviewed. For hazardous air pollutants, mainly long-term data are required. Oxidant precursors, however, some of which are very volatile, must be detected and quantified as early and

Tsuneaki Maeda; Sukeo Onodera; Hiroshi Ogino

1995-01-01

349

Heat Exhaustion, First Aid  

MedlinePLUS

newsletter | contact Share | Heat Exhaustion, First Aid A A A Heat exhaustion signs and symptoms can include heavy perspiration; nausea; lightheadedness; severe thirst; dilated pupils; and red or pale, ...

350

30 CFR 36.46 - Explosion tests of intake and exhaust systems.  

Code of Federal Regulations, 2010 CFR

...explosive natural gas-air mixture. The mixture within the intake and exhaust systems...flammable natural gas-air mixtures in the intake and exhaust systems...explosion tests of the intake and exhaust systems...surrounding flammable gas-air mixture....

2010-07-01

351

The Analysis of Exhaust Gas Thermal Energy Recovery Through a TEG Generator in City Traffic Conditions Reproduced on a Dynamic Engine Test Bed  

NASA Astrophysics Data System (ADS)

We present an analysis of thermal energy recovery through a proprietary thermoelectric generator (TEG) in an actual vehicle driving cycle reproduced on a dynamic engine test bed. The tests were performed on a 1.3-L 66-kW diesel engine. The TEG was fitted in the vehicle exhaust system. In order to assess the thermal energy losses in the exhaust system, advanced portable emission measurement system research tools were used, such as Semtech DS by Sensors. Aside from the exhaust emissions, the said analyzer measures the exhaust mass flow and exhaust temperature, vehicle driving parameters and reads and records the engine parameters. The difficulty related to the energy recovery measurements under actual traffic conditions, particularly when passenger vehicles and TEGs are used, spurred the authors to develop a proprietary method of transposing the actual driving cycle as a function V = f(t) onto the engine test bed, opn which the driving profile, previously recorded in the city traffic, was reproduced. The length of the cycle was 12.6 km. Along with the motion parameters, the authors reproduced the parameters of the vehicle and its transmission. The adopted methodology enabled high repeatability of the research trials while still ensuring engine dynamic states occurring in the city traffic.

Merkisz, Jerzy; Fuc, Pawel; Lijewski, Piotr; Ziolkowski, Andrzej; Wojciechowski, Krzysztof T.

2014-12-01

352

Combined air and water pollution control system  

NASA Technical Reports Server (NTRS)

A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

Wolverton, Billy C. (inventor); Jarrell, Lamont (inventor)

1990-01-01

353

76 FR 5368 - California State Motor Vehicle Pollution Control Standards; Greenhouse Gas Regulations; Within...  

Federal Register 2010, 2011, 2012, 2013, 2014

...PROTECTION AGENCY [FRL-9260-4] California State Motor Vehicle Pollution Control...SUMMARY: The California Air Resources Board (CARB) has notified...and is accepting written comment on California's request. DATES: EPA has...

2011-01-31

354

GREENHOUSE GAS RESEARCH AREAS (ATMOSPHERIC PROTECTION BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)  

EPA Science Inventory

The emissions programs in the Atmospheric Protection Branch (APB) of NRMRL's Air Pollution Prevention and Control Division are primarily dedicated to anthropogenic (human-influenced) sources of methane and high-global-warming refrigerants, though some work addresses carbon dioxid...

355

Transboundary Atmospheric Pollution of Oil-Gas Industry Emissions from North Caspian region of Kazakhstan  

NASA Astrophysics Data System (ADS)

The Atyraus region (Republic of Kazahstan) is occupied with more than 60 oil-gas fields which are actively developing. Moreover, a new world largest field so-called Kashagan has been discovered on the Caspian Sea shelf and its exploitation is planned by the end of 2012. In our study, this region has been selected as a source region of sulphates emissions accounting about 15 tons (2009 estimates). Three locations have been chosen in the region covering adjacent Caspian Sea aquatoria, and emissions were equally distributed among these locations (with an emission rate of 4.72*10-4 kg/sec). From original sulphates emissions between 46-82% are subjected to atmospheric transport away from the sources. Releases were considered to be continuous. The long-term modelling of atmospheric transport, dispersion and deposition of sulphates was done employing the Lagrangian type model called DERMA, run at the NEC SX6 supercomputing facilities. After each day of release the atmospheric transport has been tracked for the next 2 week period. Input meteorological 3D fields were obtained from the ECMWF data archives. The generated output included air concentration (at model levels), time integrated air concentration, dry and wet deposition (at the surface). The results of dispersion modelling had been post-processed and integrated into GIS environment (using ArcGIS). These have been further used to calculate annual averaged and summary concentration and deposition fields for administrative regions, counties and cities of Kazakhstan, as well as territories of the neighboring countries. It has been found that on an annual scale, the dominating atmospheric transport of pollution from the Atyraus region is toward east and north-east, mostly due to prevailing westerlies. Although on a hemispheric scale, the wet deposition dominates over dry (63 vs. 37%), for Kazakhstan the wet deposition contribution is slightly larger (65%). For Turkmenistan, dry deposition is almost twice higher compared with wet (65 vs. 35%) which is due to significantly smaller precipitation in this country. Considering total deposition during transboundary atmospheric transport, it should be noted that 80.3% of transported sulphates will be deposited over territories of Kazakhstan, 13.8% - Russia, about 2% each - Turkmenistan and Uzbekistan, and less than 1% over other countries. Among considered 14 Regions of Kazakhstan and 8 Federal District of Russia, the highest concentrations and depositions were identified in the Atyraus and Magistaus regions of Kazakhstan as well as in the South Federal District of Russia. For Kazakhstan, the lowest values were identified in the Almaty, East-Kazakhstan, Dzhambul and Pavlodar regions. Among most populated cities the city of Atyrau (Kazakhstan), Astrakhan (Russia) and Baku (Azerbaijan) showed the largest concentrations during transboundary atmospheric transport.

Zakarin, E.; Balakay, L.; Mirkarimova, B.; Mahura, A.; Baklanov, A.; Sorensen, J. H.

2012-04-01

356

Remote sensing of aircraft exhaust temperature and composition by passive Fourier Transform Infrared (FTIR)  

NASA Astrophysics Data System (ADS)

The scanning infrared gas imaging system (SIGIS-HR) and the quantitative gas analysis software MAPS (Multicomponent Air Pollution Software) are applied to investigate the spatial distribution of the temperature and gas concentrations (CO, NO) within the plume of aircraft engines at airports. The system integrates an infrared camera also. It is used for the localisation of the hot source that additionally suggests the best measurement position of the SIGIS-HR. The application of emission FTIR spectrometry for the measurement of temperature and gas emission index of CO and NO is presented for the exhaust of a small turbojet based on a helicopter turbine. In these measurements the emitted infrared radiation from the exhaust gas stream was collected by the SIGIS-HR at different spectral resolution (56 cm -1 and 0.2 cm -1). The software MAPS includes the Instrumental Line Shape (ILS) of the OPAG- 22 FTIR spectrometer obtained by active gas cell measurements and ILS modelling. The rough concept of the system will be presented and operational applications will be discussed. The results of the investigation of the temperature and gas concentrations (CO, NO) within the aircraft engine plumes will be shown. The limitations and of the systems will be discussed.

Flores, Edgar; Schäfer, Klaus; Black, John; Harig, Roland; Jahn, Carsten

2007-10-01

357

Bronchoalveolar inflammation after exposure to diesel exhaust: comparison between unfiltered and particle trap filtered exhaust  

PubMed Central

OBJECTIVES: Air pollution particulates have been identified as having adverse effects on respiratory health. The present study was undertaken to further clarify the effects of diesel exhaust on bronchoalveolar cells and soluble components in normal healthy subjects. The study was also designed to evaluate whether a ceramic particle trap at the end of the tail pipe, from an idling engine, would reduce indices of airway inflammation. METHODS: The study comprised three exposures in all 10 healthy never smoking subjects; air, diluted diesel exhaust, and diluted diesel exhaust filtered with a ceramic particle trap. The exposures were given for 1 hour in randomised order about 3 weeks apart. The diesel exhaust exposure apperatus has previously been carefully developed and evaluated. Bronchoalveolar lavage was performed 24 hours after exposures and the lavage fluids from the bronchial and bronchoalveolar region were analysed for cells and soluble components. RESULTS: The particle trap reduced the mean steady state number of particles by 50%, but the concentrations of the other measured compounds were almost unchanged. It was found that diesel exhaust caused an increase in neutrophils in airway lavage, together with an adverse influence on the phagocytosis by alveolar macrophages in vitro. Furthermore, the diesel exhaust was found to be able to induce a migration of alveolar macrophages into the airspaces, together with reduction in CD3+CD25+ cells. (CD = cluster of differentiation) The use of the specific ceramic particle trap at the end of the tail pipe was not sufficient to completely abolish these effects when interacting with the exhaust from an idling vehicle. CONCLUSIONS: The current study showed that exposure to diesel exhaust may induce neutrophil and alveolar macrophage recruitment into the airways and suppress alveolar macrophage function. The particle trap did not cause significant reduction of effects induced by diesel exhaust compared with unfiltered diesel exhaust. Further studies are warranted to evaluate more efficient treatment devices to reduce adverse reactions to diesel exhaust in the airways.   PMID:10492649

Rudell, B.; Blomberg, A.; Helleday, R.; Ledin, M. C.; Lundback, B.; Stjernberg, N.; Horstedt, P.; Sandstrom, T.

1999-01-01

358

A down-exhaust cyclone separator  

Microsoft Academic Search

In this paper the authors report on the development of a down-exhaust cyclone separator suitable for use as a primary device for gas-particle separation in circulating fluidized-bed (CFB) boilers. It consists of a cylindrical shell which is joined by an inclined cone, a guide body, and a downward exhaust pipe. The principle of solids separation is similar to that in

Han-Ping Chen; Zhi-Jie Lin; De-Chang Liu; Xiao S. Wang; Martin J. Rhodes

1999-01-01

359

The challenges of reducing greenhouse gas emissions and air pollution through energy sources: evidence from a panel of developed countries.  

PubMed

The objective of the study is to investigate the long-run relationship between climatic factors (i.e., greenhouse gas emissions, agricultural methane emissions, and industrial nitrous oxide emission), air pollution (i.e., carbon dioxide emissions), and energy sources (i.e., nuclear energy; oil, gas, and coal energy; and fossil fuel energy) in the panel of 35 developed countries (including EU-15, new EU member states, G-7, and other countries) over a period of 1975-2012. In order to achieve this objective, the present study uses sophisticated panel econometric techniques including panel cointegration, panel fully modified OLS (FMOLS), and dynamic OLS (DOLS). The results show that there is a long-run relationship between the variables. Nuclear energy reduces greenhouse gases and carbon emissions; however, the other emissions, i.e., agricultural methane emissions and industrial nitrous oxide, are still to increase during the study period. Electricity production from oil, gas, and coal sources increases the greenhouse gases and carbon emissions; however, the intensity to increase emissions is far less than the intensity to increase emissions through fossil fuel. Policies that reduce emissions of greenhouse gases can simultaneously alter emissions of conventional pollutants that have deleterious effects on human health and the environment. PMID:24584642

Akhmat, Ghulam; Zaman, Khalid; Shukui, Tan; Sajjad, Faiza; Khan, Muhammad Azhar; Khan, Muhammad Zahir

2014-06-01

360

Developing, Coupling, and Applying a Gas, Aerosol, Transport, and Radiation Model to Study Urban and Regional Air Pollution.  

NASA Astrophysics Data System (ADS)

This thesis discusses the development of a gas, aerosol, transport, and radiation air quality model (GATOR), the coupling of GATOR to a mesoscale meteorological and tracer dispersion model (MMTD), and the application of the resulting GATOR/MMTD air pollution modeling system (APMS) to studies of gas and aerosol pollution buildup in the Los Angeles Basin. GATOR consists of computer algorithms that simulate four groups of atmospheric processes: gas, aerosol, transport, and radiation processes. Gas processes include chemistry, emissions, gas-to-particle conversion, optical depth attenuation, and deposition. Aerosol processes include size-resolved emissions, nucleation, coagulation, condensational growth, dissolutional growth, evaporation, chemical equilibrium, aqueous chemistry, optical depth attenuation, deposition, and sedimentation. Transport processes include horizontal advection and diffusion and vertical diffusion of all gases and particles, and they require meteorological data as inputs. To drive the transport processes, the MMTD, developed by R. Lu and R. P. Turco, was coupled to GATOR. The MMTD predicts wind speed, wind direction, temperature, humidity, and pressure, among other variables. Finally, radiation processes in GATOR include spectrally-resolved scattering and absorption by gases, aerosols, fogs, and clouds, and calculation of mean intensities and heating rates. I used the GATOR/MMTD modeling system to predict pollution buildup in Los Angeles during the Southern California Air Quality Study (SCAQS) period of August 26-28, 1987. Among the model inputs were emissions, soil moisture, albedo, topographical, landuse, and chemical rate data. To validate the model, surface observations were compared to model predictions of gas-phase ozone, nitric oxide, nitrogen dioxide, carbon monoxide, sulfur dioxide, methane, total non-methane hydrocarbons, formaldehyde, peroxyacetylnitrate, hydrogen peroxide, nitric acid, nitrous acid, and ammonia concentrations. Observations were also compared to predictions of aerosol-phase ammonium, nitrate, sodium, chloride, sulfate, and total particulate concentrations. Finally, observations were compared to predictions of solar radiation and scattering coefficients. In sum, the GATOR/MMTD system predicted ozone to within a normalized gross error of 20 -35% during the study period. Additional statistics and time-series plots are shown.

Jacobson, Mark Zachary

361

The effect of thermal barrier coating on a turbo-charged Diesel engine performance and exergy potential of the exhaust gas  

Microsoft Academic Search

In this study, the effect of insulated combustion chamber surfaces on the turbocharged, direct injection Diesel engine performance was experimentally investigated. Satisfactory performance was obtained with the low heat rejection (LHR) engine. In comparison to a standard Diesel engine, specific fuel consumption was decreased by 6%, and brake thermal efficiency was increased by 2%. It was concluded that the exhaust

Adnan Parlak; Halit Yasar; Osman Eldogan

2005-01-01

362

The Proton Transfer Reaction-Mass Spectrometer for Atmospheric Chemistry Tracers of Diesel Exhaust Emissions and Measurements of Trace gas and Aerosol properties.  

E-print Network

The Proton Transfer Reaction-Mass Spectrometer for Atmospheric Chemistry Tracers of Diesel Exhaust the use of a technique referred to as the Dynamic Dilution System. The use of a Proton Transfer ReactionL/hr) Thermometers (Centigrade) Ionicon Analytik Proton Transfer Reaction-Mass Spectrometer (PTR-MS) Procedure The N2

Collins, Gary S.

363

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Code of Federal Regulations, 2012 CFR

... measurement. The use of proportional bag sampling for sample integration is allowed...measurement, but requirements specific to bag sampling from diesel exhaust must be met...using GC-FID analysis of a proportional bag sample. The mass of gaseous...

2012-07-01

364

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Code of Federal Regulations, 2013 CFR

... measurement. The use of proportional bag sampling for sample integration is allowed...measurement, but requirements specific to bag sampling from diesel exhaust must be met...using GC-FID analysis of a proportional bag sample. The mass of gaseous...

2013-07-01

365

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Code of Federal Regulations, 2011 CFR

... measurement. The use of proportional bag sampling for sample integration is allowed...measurement, but requirements specific to bag sampling from diesel exhaust must be met...using GC-FID analysis of a proportional bag sample. The mass of gaseous...

2011-07-01

366

Exposure to Diesel Exhaust Enhances the Generation of Vascular Microparticles  

EPA Science Inventory

Introduction: In the study of the health impacts of traffic-related air pollution, diesel exhaust is a pollutant of particular interest, since it is a major source of particulate matter (PM). Epidemiological studies associate exposure to ambient levels of PM with cardiovascular m...

367

Development and application of a new air pollution modeling system-part I: Gas-phase simulations  

NASA Astrophysics Data System (ADS)

A new air pollution modeling system is discussed and applied. The system consists of GATOR, a gas, aerosol, transport, and radiation air quality model and MMTD, a mesoscale meteorological and tracer dispersion model. The gas-phase processes treated by GATOR include photochemistry, deposition, emissions, and gas-to-particle conversion. To solve stiff chemical rate equations, a sparse-matrix, vectorized Gear-type code (SMVGEAR) was used. The aerosol processes in GATOR include coagulation, aqueous chemistry, chemical equilibrium, condensational growth, dissolutional growth, evaporation, nucleation, emissions, deposition, and sedimentation. The transport processes include horizontal advection and diffusion and vertical convection and diffusion. Finally, the radiation algorithm calculates ultraviolet, visible, and infrared optical depths, mean intensities for photodissociation rates, and radiative heat fluxes for temperature calculations. The MMTD predicts winds, diffusion, temperature, pressure, humidity, soil moisture, and rainfall. These variables are fed to GATOR and radiative heating rates from GATOR are fed back to the MMTD. With the GATOR/MMTD system, gas-phase pollution was simulated for the Southern California Air Quality Study (SCAQ) days of 26-28 August 1987. Results were compared to surface measurements for many parameters. The model predicted normalized gross errors for ozone of 17.6% and 23.4% at 2:30 p.m. on the first and second days of simulation, respectively. Also, the normalized gross error during the first 12 h of simulation was 22%. Correct emissions and initial mixing ratios appear to be necessary for obtaining good results. Initial conditions outside the basin seem to affect results by the second and third days. Time-series plots, statistics, and a sensitivity test are discussed. Aerosol simulation results will be shown in a later work.

Jacobson, Mark Z.; Lu, Rong; Turco, Richard P.; Toon, Owen B.

368

Characterization of polar polycyclic aromatic compounds in a heavy-duty diesel exhaust particulate by capillary column gas chromatography and high-resolution mass spectrometry  

SciTech Connect

Polar normal-phase HPLC fractions of a heavy-duty diesel exhaust particulate, a National Bureau of Standards (NBS) standard reference material (SRM) 1650, were analyzed by capillary column GC coupled to both low- and high-resolution mass spectrometry (HRMS) using electron impact (EI) and negative ion chemical ionization (NICI). Over 80 polycyclic aromatic compounds (PAC), belonging to many different chemical classes (anhydrides, carboxaldehydes, diazaarenes, cyclic imides, nitrohydroxy-PAC, nitroaza-PAC, nitrodiaza-PAC, nitrolactones, and quinones) were tentatively identified. Ten of them were positively identified by comparison of retention times with authentic standards. Among them, phenazine and phthalic anhydride were positively identified for the first time in diesel exhaust particulates. In addition, cyclic imides and their alkylated derivatives were tentatively identified for the first time. Other novel polar chemical classes of PAC were evidenced by MICI MS using a direct-insertion probe.

Bayona, J.M.; Markides, K.E.; Lee, M.L.

1988-12-01

369

Duplex tab exhaust nozzle  

NASA Technical Reports Server (NTRS)

An exhaust nozzle includes a conical duct terminating in an annular outlet. A row of vortex generating duplex tabs are mounted in the outlet. The tabs have compound radial and circumferential aft inclination inside the outlet for generating streamwise vortices for attenuating exhaust noise while reducing performance loss.

Gutmark, Ephraim Jeff (Inventor); Martens, Steven (nmn) (Inventor)

2012-01-01

370

Exhaust backpressure tester  

Microsoft Academic Search

This patent describes a method for measuring exhaust backpressure in an internal combustion engine. It comprises: providing a pressure indicating device of the type having an elongate probe which communicates fluid pressure to an interior portion of the device; locating a wall of a manifold, pipe, muffler, catalytic converter or which is in fluid communication with an exhaust port of

1989-01-01

371

Toxic Acid Gas Absorber Design Considerations for Air Pollution Control in Process Industries  

ERIC Educational Resources Information Center

This paper analyses the design parameters for an absorber used for removal of toxic acid gas (in particular sulfur dioxide) from a process gas stream for environmental health protection purposes. Starting from the equilibrium data, Henry's law constant was determined from the slope of the y-x diagram. Based on mass balances across the absorber,…

Manyele, S. V.

2008-01-01

372

Relationship of Atmospheric Pollution Characterized by Gas (NO 2 ) and Particles (PM10) to Microbial Communities Living in Bryophytes at Three Differently Polluted Sites (Rural, Urban, and Industrial)  

Microsoft Academic Search

Atmospheric pollution has become a major problem for modern societies owing to its fatal effects on both human health and\\u000a ecosystems. We studied the relationships of nitrogen dioxide atmospheric pollution and metal trace elements contained in atmospheric\\u000a particles which were accumulated in bryophytes to microbial communities of bryophytes at three differently polluted sites\\u000a in France (rural, urban, and industrial) over

Caroline Meyer; Daniel Gilbert; André Gaudry; Marielle Franchi; Hung Nguyen-Viet; Juliette Fabure; Nadine Bernard

2010-01-01

373

Performance assessment of U.S. residential cooking exhaust hoods.  

PubMed

This study assessed the performance of seven new residential cooking exhaust hoods representing common U.S. designs. Laboratory tests were conducted to determine fan curves relating airflow to duct static pressure, sound levels, and exhaust gas capture efficiency for front and back cooktop burners and the oven. Airflow rate sensitivity to duct flow resistance was higher for axial fan devices than for centrifugal fan devices. Pollutant capture efficiency (CE) ranged from <15% to >98%, varying across hoods and with airflow and burner position for each hood. CE was higher for back burners relative to front burners, presumably because most hoods covered only part of the front burners. Open hoods had higher CE than those with grease screen and metal-covered bottoms. The device with the highest CE--exceeding 80% for oven and front burners--had a large, open hood that covered most of the front burners. The airflow rate for this hood surpassed the industry-recommended level of 118 L·s(-1) (250 cfm) and produced sound levels too high for normal conversation. For hoods meeting the sound and fan efficacy criteria for Energy Star, CE was <30% for front and oven burners. PMID:22568807

Delp, William W; Singer, Brett C

2012-06-01

374

Recent developments and applications with gas cell correlation spectrometer. [IR sensing of air pollution  

NASA Technical Reports Server (NTRS)

Gaspec, a gas filter correlation spectrometer, is described. Gaspec is a dual-gas three-channel instrument using two detectors which receive amplitude-shared source signals modulated at the frequency of the chopper. Several units for operation around the 3-5 micron and the 8-15 micron region have been constructed, and gases such as CO2, CO, CH4, HCl, NO, and hydrazines can be detected. Advantages of Gaspec are considered with reference to improvements developed for the basic Cospec (gas cell correlation spectrometer) instrument.

Barringer, A. R.; Davies, J. H.; Floyd, G.

1978-01-01

375

Space shuttle exhaust cloud properties  

NASA Technical Reports Server (NTRS)

A data base describing the properties of the exhaust cloud produced by the launch of the Space Transportation System and the acidic fallout observed after each of the first four launches was assembled from a series of ground and aircraft based measurements made during the launches of STS 2, 3, and 4. Additional data were obtained from ground-based measurements during firings of the 6.4 percent model of the Solid Rocket Booster at the Marshall Center. Analysis indicates that the acidic fallout is produced by atomization of the deluge water spray by the rocket exhaust on the pad followed by rapid scavening of hydrogen chloride gas aluminum oxide particles from the Solid Rocket Boosters. The atomized spray is carried aloft by updrafts created by the hot exhaust and deposited down wind. Aircraft measurements in the STS-3 ground cloud showed an insignificant number of ice nuclei. Although no measurements were made in the column cloud, the possibility of inadvertent weather modification caused by the interaction of ice nuclei with natural clouds appears remote.

Anderson, B. J.; Keller, V. W.

1983-01-01

376

Diesel Exhaust Inhalation Increases Cardiac Output, Bradyarrhythmias, and Parasympathetic Tone in Aged Heart Failure-Prone Rats  

EPA Science Inventory

Acute air pollutant inhalation is linked to adverse cardiac events and death, and hospitalizations for heart failure. Diesel exhaust (DE) is a major air pollutant suspected to exacerbate preexisting cardiac conditions, in part, through autonomic and electrophysiologic disturbance...

377

Examination of cytokines and metals in exhaled breath condensate and lung lavage fluids after diesel exhaust exposure  

EPA Science Inventory

Epidemiology studies link human exposure to ambient air pollution with the development and exacerbation of cardiopulmonary disease. Diesel exhaust (DE) is a significant source of ambient air pollution, and thus may contribute to adverse pulmonary health effects. Previous human re...

378

Elevated exhaust temperature, zoned, electrically-heated particulate matter filter  

DOEpatents

A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

2012-04-17

379

Greenhouse Gas and Criteria Air Pollutant Emission Reductions from Forest Fuel Treatment Projects in Placer County, California  

NASA Astrophysics Data System (ADS)

Years of successful fire suppression activities have left forests unnaturally dense, overstocked, and with high hazardous fuel loads. Wildfires, particularly those of high severity, may dramatically reduce carbon stocks and convert forested lands from carbon sinks to decades-long carbon sources . Forest resource managers are currently pursuing fuels reduction and mitigation strategies to reduce wildfire risk and maintain carbon stocks. These projects include selective thinning and removal of trees and brush to return forest ecosystems to more natural stocking levels, resulting in a more fire-resilient forest that in theory would retain higher carry capacity for standing above ground carbon. Resource managers are exploring the possibility of supporting these local forest management projects by offering greenhouse gas (GHG) offsets to project developers that require GHG emissions mitigation. Using robust field data, this research project modeled three types of carbon benefits that could be realized from forest management: 1. Fuels treatments in the study area were shown to reduce the GHG and Criteria Air Pollutant emissions from wildfires by decreasing the probability, extent, and severity of fires and the corresponding loss in forest carbon stocks; 2. Biomass utilization from fuel treatment was shown to reduce GHG and Criteria Air Pollutant emissions over the duration of the fuels treatment project compared to fossil fuel energy. 3. Management and thinning of forests in order to stimulate growth, resulting in more rapid uptake of atmospheric carbon and approaching a carbon carrying capacity stored in a forest ecosystem under prevailing environmental conditions and natural disturbance regimes.

Saah, D. S.; Moritz, M.; Ganz, D. J.; Stine, P. A.; Moody, T.

2010-12-01

380

Gas exchange, growth, and chemical parameters in a native Atlantic forest tree species in polluted areas of Cubatão, Brazil.  

PubMed

The Atlantic forest species near the industrial complex of Cubatão, Brazil have been subjected to heavy air pollution for decades. In this study, we used some physiological parameters (gas exchange, growth and chemical contents) to biomonitor the effects of air pollution on Tibouchina pulchra, one of the most common tree species in this forest. Under standardized conditions, saplings were exposed to the environment from April to July and from July to September of 1998, at three different sites in the vicinity of the industrial complex: the Valley of Pilões River (VP), the control area; the Valley of Mogi River (VM), near fertilizer, metallurgical, and cement industries sustaining high concentrations of fluorides, N and S oxides, and particulate materials; and Caminho do Mar (CM), near petrochemical industries under N and S oxides, photooxidants, and organic compounds. Plants exposed to CM and VM conditions presented visible injuries, reductions in net photosynthesis, growth parameters, and ascorbate concentrations, and increased F, N, and S foliar concentrations. These results indicate that the environmental conditions around these industries are still harmful to plants. PMID:12651190

Moraes, R M; Delitti, W B C; Moraes, J A P V

2003-03-01

381

Large-scale time-resolved digital particle image velocimetry (TR-DPIV) for measurement of high subsonic hot coaxial jet exhaust of a gas turbine engine  

NASA Astrophysics Data System (ADS)

The development of a highly configurable triple digital particle image velocimetry (DPIV) system is described, which is capable of acquiring both continuous, statistically independent measurements at up to 14 Hz and time-resolved PIV data at MHz rates. The system was used at QinetiQ's Noise Test Facility (NTF) as part of the EU-funded CoJeN programme to obtain measurements from high subsonic (Mach <= 0.9), hot (~500 °C), large (1/10th) scale coaxial jet flows at a standoff distance of ~1 m. High-resolution time-averaged velocity and turbulence data were obtained for complete coaxial engine exhaust plumes down to 4 m (20 jet diameters) from the nozzle exit in less than 1 h. In addition, the system allowed volumetric data to be obtained, enabling fast assessment of spatial alignment of nozzle configurations. Furthermore, novel six-frame time-series data-capture is demonstrated up to 330 kHz, used to calculate time-space correlations within the exhaust, allowing for study of spatio-temporal developments in the jet, associated with jet-noise production. The highly automated system provides synchronization triggers for simultaneous acquisition from different measurement systems (e.g. LDA) and is shown to be versatile, rugged, reliable and portable, operating remotely in a hostile environment. Data are presented for three operating conditions and two nozzle geometries, providing a database to be used to validate CFD models of coaxial jet flow.

Timmerman, B. H.; Skeen, A. J.; Bryanston-Cross, P. J.; Graves, M. J.

2009-07-01

382

The investigation of exhaust powered, automotive air cycle air conditioning  

E-print Network

-Vane Air-Cycle Air-Conditioning and Refrigeration System, " SAE Paper No. 720079, 1972. 7. Edwards, T. C. , "The Rovac Automotive Air Conditioning System, " SAE Paper No. 75043, 1975 ' 8. Boyce, M. P. , "The Utilization of Internal Combustion Engine... Exhaust, for Air Conditioning, " SAE Paper No. 719162, 1971. 9. Christensen, A. J. , "Utilization of Internal Combustion Engine Exhaust for Air Conditioning, Supercharging, and Pollution Control, " Masters Thesis, Texas A8R University, December 1970...

Holley, James Andrew

1978-01-01

383

Atmospheric scavenging exhaust  

NASA Technical Reports Server (NTRS)

Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.

Fenton, D. L.; Purcell, R. Y.

1977-01-01

384

EXHAUST EMISSIONS FROM A DIESEL ENGINE  

EPA Science Inventory

Studies were performed using (1) Diesel particles collected from the undiluted exhaust of a single-cylinder engine, operated at constant speed and load, using a binary pure hydrocarbon fuel with air or gas mixture oxidizers, and (2) Diesel particles collected from the diluted exh...

385

Effects of water-emulsified fuel on a diesel engine generator's thermal efficiency and exhaust.  

PubMed

Water-emulsified diesel has proven itself as a technically sufficient improvement fuel to improve diesel engine fuel combustion emissions and engine performance. However, it has seldom been used in light-duty diesel engines. Therefore, this paper focuses on an investigation into the thermal efficiency and pollution emission analysis of a light-duty diesel engine generator fueled with different water content emulsified diesel fuels (WD, including WD-0, WD-5, WD-10, and WD-15). In this study, nitric oxide, carbon monoxide, hydrocarbons, and carbon dioxide were analyzed by a vehicle emission gas analyzer and the particle size and number concentration were measured by an electrical low-pressure impactor. In addition, engine loading and fuel consumption were also measured to calculate the thermal efficiency. Measurement results suggested that water-emulsified diesel was useful to improve the thermal efficiency and the exhaust emission of a diesel engine. Obviously, the thermal efficiency was increased about 1.2 to 19.9%. In addition, water-emulsified diesel leads to a significant reduction of nitric oxide emission (less by about 18.3 to 45.4%). However the particle number concentration emission might be increased if the loading of the generator becomes lower than or equal to 1800 W. In addition, exhaust particle size distributions were shifted toward larger particles at high loading. The consequence of this research proposed that the water-emulsified diesel was useful to improve the engine performance and some of exhaust emissions, especially the NO emission reduction. Implications: The accumulated test results provide a good basis to resolve the corresponding pollutants emitted from a light-duty diesel engine generator. By measuring and analyzing transforms of exhaust pollutant from this engine generator, the effects of water-emulsified diesel fuel and loading on emission characteristics might be more clear. Understanding reduction of pollutant emissions during the use of water-emulsified diesel helps improve the effectiveness of the testing program. The analyzed consequences provide useful information to the government for setting policies to curb pollutant emissions from a light-duty diesel engine generator more effectively. PMID:25185398

Syu, Jin-Yuan; Chang, Yuan-Yi; Tseng, Chao-Heng; Yan, Yeou-Lih; Chang, Yu-Min; Chen, Chih-Chieh; Lin, Wen-Yinn

2014-08-01

386

EFFECTIVE CONTROL OF SECONDARY WATER POLLUTION FROM FLUE GAS DESULFURIZATION SYSTEMS  

EPA Science Inventory

The report describes tests to demonstrate the feasibility of using a vertical-tube, falling-film, vapor-compression evaporator to concentrate waste water from a flue gas desulfurization (FGD) process. Tests showed that waste water from the Chiyoda FGD process can be concentrated ...

387

DRY FLUE GAS CLEANING PROCESSES FOR ACHIEVING AIR POLLUTANT EMISSIONS REQUIREMENTS  

EPA Science Inventory

The paper discusses both municipal waste combustor (MWC) rules and basic dry flue gas cleaning (FCC) processes, and compares the performance of the latter using field test data. Methods to supplement dry FCC processes for improving the control of mercury and organics are addresse...

388

Spontaneous UV-emission from nitrogen and rare-gas halogen excimers in a fast-flowing crossed-beam plasma-mixing device for pollution control  

SciTech Connect

Air pollution, water (under ground or ground), and soil contamination have become major issues with increasing industrialization. In addition to conventional incineration techniques, non-thermal plasma techniques and photolysis have been demonstrated to be very powerful tools converting pollutants into harmless chemicals. The use of excimer lamps for pollution control provides an important advantage. Emission spectrum of excimer molecules depends on the type of the gas molecules in the discharge tube forming the particular excimer molecule. Therefore, by choosing the adequate gas mixture, an emission may be found which coincides with the absorption maximum of the pollutant. One other advantage of using excimer lamps is the high efficiency of these lamps in the UV region compared to the conventional lamps. The photon energy efficiency of an excimer lamp can be as high as 10% depending on the design. The authors have developed the technique of fast plasma mixing which overcomes some of the disadvantages of excimer generation in a glow discharge, or in an electron beam sustained gas discharge, and offers an effective way to generate continuous wave UV radiation. This technique utilizes near resonant energy and charge transfer from metastable rare gas atoms and ions to molecules. A fast-flowing crossed-beam plasma mixing device can be utilized to obtain high efficiency UV lamps for industrial use. In this work, basic concepts of the crossed-beam plasma-mixing device operation are presented.

Kirkici, H.; Kralovec, J. [Auburn Univ., AL (United States). Electrical Engineering Dept.

1995-12-31

389

Chemistry and the Internal Combustion Engine II: Pollution Problems.  

ERIC Educational Resources Information Center

Discusses pollution problems which arise from the use of internal combustion (IC) engines in the United Kingdom (UK). The IC engine exhaust emissions, controlling IC engine pollution in the UK, and some future developments are also included. (HM)

Hunt, C. B.

1979-01-01

390

Entake or exhaust valve actuator  

Microsoft Academic Search

Intake or exhaust valve actuator assembly is described for an internal combustion engine for hydraulically opening and closing an intake or exhaust valve for admitting intake gases from an intake conduit into a combustion chamber or permitting exhaust gases to escape from the combustion chamber into an exhaust conduit, the engine including a piston which oscillates in the combustion chamber,

Smietana

1993-01-01

391

[Evaluation of treatment technology of odor pollution source in petrochemical industry].  

PubMed

Using an environmental technology assessment system, we put forward the evaluation index system for treatment technology of the typical odor pollution sources in the petroleum refining process, which has been applied in the assessment of the industrial technology. And then the best available techniques are selected for emissions of gas refinery sewage treatment plant, headspace gas of acidic water jars, headspace gas of cold coke jugs/intermediate oil tank/dirty oil tank, exhaust of oxidative sweetening, and vapors of loading and unloading oil. PMID:24640922

Mu, Gui-Qin; Sui, Li-Hua; Guo, Ya-Feng; Ma, Chuan-Jun; Yang, Wen-Yu; Gao, Yang

2013-12-01

392

Utilization of coal mine ventilation exhaust as combustion air in gas-fired turbines for electric and/or mechanical power generation. Semi-annual topical report, June 1995--August 1995  

SciTech Connect

Methane emitted during underground coal mining operations is a hazard that is dealt with by diluting the methane with fresh air and exhausting the contaminated air to the atmosphere. Unfortunately this waste stream may contain more than 60% of the methane resource from the coal, and in the atmosphere the methane acts as a greenhouse gas with an effect about 24.5 times greater than CO{sub 2}. Though the waste stream is too dilute for normal recovery processes, it can be used as combustion air for a turbine-generator, thereby reducing the turbine fuel requirements while reducing emissions. Preliminary analysis indicates that such a system, built using standard equipment, is economically and environmentally attractive, and has potential for worldwide application.

NONE

1995-12-01

393

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objectives of this report period were to continue and complete testing of the Gas Generator hardware, to complete and submit a Draft Final Report, and after incorporation of adjustments required, to then submit the Final Report. Focus during this report period was initially on testing the Gas Generator. While conducting scheduled full power tests of the Gas Generator at the facilities of the testing sub-contractor, National Testing Services [NTS], in Santa Clarita CA, anomalies in the performance of the Gas Generator were discovered. All testing was stopped on November 6, 2002. An expert team was formed to evaluate the anomalies and to recommend any appropriate corrective actions. After extensive analyses of the actual hardware, the test data acquired and recorded during testing, and a review of the test facilities and procedures, the Anomalies Review Team recommended that CES modify the combustion chamber front end cooling method and modify the configuration of the diluent injectors downstream of the combustion chamber, to eliminate the anomalies. At a review meeting convened in Sacramento CA on November 23, 2002, outside experts from the Lawrence Livermore National Laboratory, Air Liquide's Research Center in Chicago IL, and the California Energy Commission, confirmed that the expert team's assessed cause of the problem was the likely cause, and the recommended corrective actions were appropriate. Modified hardware drawings were produced in late November-early December 2002, hardware fabrication was begun in December, and was in process at the end of December. Also during December, the NTS test facility was being adjusted to take account of the modified hardware configuration being produced. All work was aimed toward realizing a schedule of resumed testing by mid-January for completion of tests by end of January or early February, 2003. Original objectives of the program remain in place and approximately ninety (90) percent of those objectives had been completed prior to discovery of the anomalies. The accomplished objectives to date are described in this report.

Stephen E. Doyle

2002-12-31

394

EVALUATION OF A PROPORTIONAL SAMPLER FOR AUTOMOTIVE EXHAUST EMISSIONS  

EPA Science Inventory

A test program was conducted to evaluate a proportional sampler for use in automotive exhaust gas emissions research. Automobile emissions test results obtained using the proportional sampler were compared with results obtained using the conventional constant volume sampler. Meas...

395

Comparing the CO Content of Cigarette Smoke and Auto Exhaust  

NSDL National Science Digital Library

This lab exercise investigates and compares the carbon monoxide content of automobile exhaust and cigarette smoke. The experiment uses gas chromatography with thermal conductivity detection to analyze the percentage by volume concentrations found in cigar

Dan Jaffe

1999-12-01

396

Determination of sulfur trioxide in engine exhaust.  

PubMed Central

Sulfur trioxide in the exhaust gas of an internal combustion engine is removed and concentrated by absorption in a solution of 80% isopropyl alcohol, which quantitatively absorbs it and inhibits the oxidation of any sulfur dioxide which may be absorbed. The absorbed sulfur trioxide (sulfuric acid) is determined by an absorption titration by using barium chloride as the titrant and thorin as the indicator. The sulfur dioxide content of the exhaust is measured continuously by means of a DuPont Model 411 ultraviolet photoanalyzer. PMID:50930

Arnold, D R

1975-01-01

397

Active exhaust silencers quiet diesel generator sets  

SciTech Connect

This article describes newly developed active noise cancellation technology which silences engines without sacrificing efficiency and performance. The first real attempts at active noise cancellation occurred in the 1930s. Unfortunately, the success of these initial attempts was limited because, even with very simple applications, the rudimentary control systems available at the time were not up to the task. However, with the advent of digital signal processing technology and improved transducers, it is now possible to apply active noise cancellation technology commercially. Active silencers have been demonstrated successfully on automobiles, trucks, buses, compressors, very large natural gas engines and positive displacement blowers. Active silencers attenuate exhaust noise and can reduce exhaust backpressure.

Shipps, J.C.; Miller, S.K.; Shaver, J.

1994-08-01

398

Determination of organic priority pollutants in sewage treatment plant effluents by gas chromatography high-resolution mass spectrometry.  

PubMed

In this work, we report the development and validation of an analytical method for the trace level determination of 14 selected (EU-directive) priority organic pollutants (namely, 1,2,3-trichlorobenzene (1,2,3-TCB), 1,2,4-trichlorobenzene, 1,3,5-trichlorobenzene, hexachloro-1,3-butadiene, pentachlorobenzene, hexachlorobenzene, alachlor, alpha-hexachloro-cyclohexane (alpha-HCH), beta-HCH, gamma-HCH (lindane), delta-HCH, tetra-brominated diphenyl ether (tetra-BDE), penta-brominated diphenyl ether and hepta-brominated diphenyl ether) in wastewater samples from 5 different sewage treatment plants (STPs) located in Spain. The proposed methodology is based on liquid-liquid extraction with n-hexane followed by identification and confirmation of the selected pollutants by gas chromatography high-resolution mass spectrometry in selected ion recording acquisition mode. Recovery studies performed with spiked wastewater samples at two different concentration levels (0.1 and 1 microg L(-1)) gave mean recoveries in the range 80-120% (except for trichlorobenzenes, ca. with 50%) with RSD values below 10% in most cases, thus confirming the usefulness of the proposed methodology for the analyses of this kind of complex samples. The obtained detection limits in effluent wastewater matrices were in the low nanogram per liter range, with values as low as 0.09 ng L(-1) for tetra-BDE and 0.3 ng L(-1) for hexachlorobenzene. Finally, the proposed methodology was successfully applied to a monitoring study intended to characterize wastewater effluents of 5 different sewage treatment plants with different major activities (Industrial, Coastal, Urban). Most of the compounds targeted were detected in the ng L(-1) range at concentrations ranging from 0.19 ng L(-1) to 135 ng L(-1) (hexachlorobenzene). PMID:20801335

Robles-Molina, José; Gilbert-López, Bienvenida; García-Reyes, Juan F; Molina-Díaz, Antonio

2010-09-15

399

Study of Recovery of Waste Heat From the Exhaust of Automotive Engine  

Microsoft Academic Search

Automotive engines reject a considerable amount of energy to the ambience through the exhaust gas. Significant reduction of engine fuel consumption could be attained by recovering of exhaust heat by using thermoelectric generators. One of the most important issues is to develop an efficient heat exchanger which provides optimal recovery of heat from exhaust gases. The work presents a design

K. Wojciechowski; P. Lijewski; M. Schmidt

400

Int. J. Environment and Pollution, V0/. IS, No.4, 2001 Economic evaluation of a landfill system with gas  

E-print Network

Int. J. Environment and Pollution, V0/. IS, No.4, 2001 Economic evaluation of a landfill system recovery for municipal solid waste management: a case study', Int. J. Environment and Pollution, Vol. 15,No results in increasing environmental pollution. The state of an economy, to a large extent, influences

Columbia University

401

Exhaust backpressure tester  

SciTech Connect

This patent describes a method for measuring exhaust backpressure in an internal combustion engine. It comprises: providing a pressure indicating device of the type having an elongate probe which communicates fluid pressure to an interior portion of the device; locating a wall of a manifold, pipe, muffler, catalytic converter or which is in fluid communication with an exhaust port of the internal combustion engine; creating a bore through the wall of a size sufficient to just receive the probe therethrough; inserting the probe in the bore in unsealed and unthreaded relation therewith; reading the backpressure indicated by the device; withdrawing the probe from the bore; and inserting a plug into the bore. The plug having a diameter sufficient to frictionally engage the radially inner surface of the bore thereby plugging the bore against exhaust leakage.

Freeman, F.F.

1989-12-12

402

Two-stage combustion for reducing pollutant emissions from gas turbine combustors  

NASA Technical Reports Server (NTRS)

Combustion and emission results are presented for a premix combustor fueled with admixtures of JP5 with neat H2 and of JP5 with simulated partial-oxidation product gas. The combustor was operated with inlet-air state conditions typical of cruise power for high performance aviation engines. Ultralow NOx, CO and HC emissions and extended lean burning limits were achieved simultaneously. Laboratory scale studies of the non-catalyzed rich-burning characteristics of several paraffin-series hydrocarbon fuels and of JP5 showed sooting limits at equivalence ratios of about 2.0 and that in order to achieve very rich sootless burning it is necessary to premix the reactants thoroughly and to use high levels of air preheat. The application of two-stage combustion for the reduction of fuel NOx was reviewed. An experimental combustor designed and constructed for two-stage combustion experiments is described.

Clayton, R. M.; Lewis, D. H.

1981-01-01

403

CONTROL OF POLLUTANT EMISSIONS IN NATURAL GAS DIFFUSION FLAMES BY USING CASCADE BURNERS  

SciTech Connect

The advanced CFDRC software package was installed on a SUN-SPARC dual processor workstation (UTPA funded). The literature pertinent to the project was collected. The physical model was set and all parameters and variables were identified. Based on the physical model, the geometric modeling and grid generation processes were performed using the CFD-GEOM (Interactive Geometric Modeling and Grid Generation software). A total number of 11160 cells (248 x 45) were generated. The venturis in the cascade were modeled as two-dimensional axisymmetric convergent nozzles around the jet. With the cascade being added to the jet, the geometric complexity of the problem increased; which required multi-domain structured grid systems to be connected and matched on the boundaries. The natural gas/propane jet diffusion flame is being numerically analyzed. The numerical computations are being conducted using the CFDRC-ACE+ (advanced computational environment) software package. The results are expected soon.

Ala Qubbaj

2001-03-30

404

Hyperventilation and exhaustion syndrome  

PubMed Central

Chronic stress is among the most common diagnoses in Sweden, most commonly in the form of exhaustion syndrome (ICD-10 classification – F43.8). The majority of patients with this syndrome also have disturbed breathing (hyperventilation). The aim of this study was to investigate the association between hyperventilation and exhaustion syndrome. Thirty patients with exhaustion syndrome and 14 healthy subjects were evaluated with the Nijmegen Symptom Questionnaire (NQ). The participants completed questionnaires about exhaustion, mental state, sleep disturbance, pain and quality of life. The evaluation was repeated 4 weeks later, after half of the patients and healthy subjects had engaged in a therapy method called ‘Grounding’, a physical exercise inspired by African dance. The patients reported significantly higher levels of hyperventilation as compared to the healthy subjects. All patients’ average score on NQ was 26.57 ± 10.98, while that of the healthy subjects was 15.14 ± 7.89 (t = ?3.48, df = 42, p < 0.001). The NQ scores correlated strongly with two measures of exhaustion (Karolinska Exhaustion Scale KES r = 0.772, p < 0.01; Shirom Melamed Burnout Measure SMBM r = 0.565, p < 0.01), mental status [Hospital Anxiety and Depression Score (HADS) depression r = 0.414, p < 0.01; HADS anxiety r = 0.627, p < 0.01], sleep disturbances (r = ?0.514, p < 0.01), pain (r = ?.370, p < 0.05) and poor well-being (Medical Outcomes Survey Short Form 36 questionnaire- SR Health r = ?0.529, p < 0.05). In the logistic regression analysis, the variance in the scores from NQ were explained to a high degree (R2 = 0.752) by scores in KES and HADS. The brief Grounding training contributed to a near significant reduction in hyperventilation (F = 2.521, p < 0.124) and to significant reductions in exhaustion scores and scores of depression and anxiety. The conclusion is that hyperventilation is common in exhaustion syndrome patients and that it can be reduced by systematic physical therapy such as Grounding. PMID:24134551

Ristiniemi, Heli; Perski, Aleksander; Lyskov, Eugene; Emtner, Margareta

2014-01-01

405

Hyperventilation and exhaustion syndrome.  

PubMed

Chronic stress is among the most common diagnoses in Sweden, most commonly in the form of exhaustion syndrome (ICD-10 classification - F43.8). The majority of patients with this syndrome also have disturbed breathing (hyperventilation). The aim of this study was to investigate the association between hyperventilation and exhaustion syndrome. Thirty patients with exhaustion syndrome and 14 healthy subjects were evaluated with the Nijmegen Symptom Questionnaire (NQ). The participants completed questionnaires about exhaustion, mental state, sleep disturbance, pain and quality of life. The evaluation was repeated 4 weeks later, after half of the patients and healthy subjects had engaged in a therapy method called 'Grounding', a physical exercise inspired by African dance. The patients reported significantly higher levels of hyperventilation as compared to the healthy subjects. All patients' average score on NQ was 26.57 ± 10.98, while that of the healthy subjects was 15.14 ± 7.89 (t = -3.48, df = 42, p < 0.001). The NQ scores correlated strongly with two measures of exhaustion (Karolinska Exhaustion Scale KES r = 0.772, p < 0.01; Shirom Melamed Burnout Measure SMBM r = 0.565, p < 0.01), mental status [Hospital Anxiety and Depression Score (HADS) depression r = 0.414, p < 0.01; HADS anxiety r = 0.627, p < 0.01], sleep disturbances (r = -0.514, p < 0.01), pain (r = -.370, p < 0.05) and poor well-being (Medical Outcomes Survey Short Form 36 questionnaire- SR Health r = -0.529, p < 0.05). In the logistic regression analysis, the variance in the scores from NQ were explained to a high degree (R(2) = 0.752) by scores in KES and HADS. The brief Grounding training contributed to a near significant reduction in hyperventilation (F = 2.521, p < 0.124) and to significant reductions in exhaustion scores and scores of depression and anxiety. The conclusion is that hyperventilation is common in exhaustion syndrome patients and that it can be reduced by systematic physical therapy such as Grounding. PMID:24134551

Ristiniemi, Heli; Perski, Aleksander; Lyskov, Eugene; Emtner, Margareta

2014-12-01

406

Polycyclic aromatic hydrocarbon exhaust emissions from different reformulated diesel fuels and engine operating conditions  

NASA Astrophysics Data System (ADS)

The study of light-duty diesel engine exhaust emissions is important due to their impact on atmospheric chemistry and air pollution. In this study, both the gas and the particulate phase of fuel exhaust were analyzed to investigate the effects of diesel reformulation and engine operating parameters. The research was focused on polycyclic aromatic hydrocarbon (PAH) compounds on particulate phase due to their high toxicity. These were analyzed using a gas chromatography-mass spectrometry (GC-MS) methodology. Although PAH profiles changed for diesel fuels with low-sulfur content and different percentages of aromatic hydrocarbons (5-25%), no significant differences for total PAH concentrations were detected. However, rape oil methyl ester biodiesel showed a greater number of PAH compounds, but in lower concentrations (close to 50%) than the reformulated diesel fuels. In addition, four engine operating conditions were evaluated, and the results showed that, during cold start, higher concentrations were observed for high molecular weight PAHs than during idling cycle and that the acceleration cycles provided higher concentrations than the steady-state conditions. Correlations between particulate PAHs and gas phase products were also observed. The emission of PAH compounds from the incomplete combustion of diesel fuel depended greatly on the source of the fuel and the driving patterns.

Borrás, Esther; Tortajada-Genaro, Luis A.; Vázquez, Monica; Zielinska, Barbara

2009-12-01

407

Pollutant emissions reduction and performance optimization of an industrial radiant tube burner  

SciTech Connect

This paper presents the results of an experimental investigation performed upon a single-ended self-recuperative radiant tube burner fuelled by natural gas in the non-premixed mode, which is used in the steel industry for surface treatment. The main goal of the research activity was a systematic investigation of the burner aimed to find the best operating conditions in terms of optimum equivalence ratio, thermal power and lower pollutant emissions. The analysis, which focused on the main parameters influencing the thermal efficiency and pollutant emissions at the exhaust (NO{sub x} and CO), has been carried out for different operating conditions of the burner: input thermal powers from 12.8 up to 18kW and equivalence ratio from 0.5 (very lean flame) to 0.95 (quasi-stoichiometric condition). To significantly reduce pollutant emissions ensuring at the same time the thermal requirements of the heating process, it has been developed a new burner configuration, in which a fraction of the exhaust gases recirculates in the main combustion region through a variable gap between the burner efflux and the inner flame tube. This internal recirculation mechanism (exhaust gases recirculation, EGR) has been favoured through the addition of a pre-combustion chamber terminated by a converging nozzle acting as a mixing/ejector to promote exhaust gas entrainment into the flame tube. The most important result of this solution was a decrease of NO{sub x} emissions at the exhaust of the order of 50% with respect to the original burner geometry, for a wide range of thermal power and equivalence ratio. (author)

Scribano, Gianfranco; Solero, Giulio; Coghe, Aldo [Dipartimento di Energetica, Politecnico di Milano, via La Masa, 34, 20156 Milano (Italy)

2006-07-15

408

Pollution Control  

NSDL National Science Digital Library

Pollution takes many forms, such as ground, air, and water pollution. To make the environment pleasant to live in, certain methods are needed to clean up pollution or, even better, to prevent it all together. Several technologies and engineering techniques are regularly employed to keep pollution in check.The Air Pollution Control Technology Handbook (1) takes an in-depth look at many types of systems used in control equipment. Although the link on the page only shows the table of contents, each entry is hyperlinked to the full text. The online version of the Pollution Engineering magazine (2) has news and information about environmental control issues. A monthly publication, it stresses the economic benefits that can be realized with proper practices. Eight environmental technology verification centers can be accessed from this Web site (3). Operated by the US Environmental Protection Agency (EPA), the centers focus on greenhouse gas technology, advanced monitoring systems, water quality protection, air pollution control, and more. Recycling is something that many people do to reduce waste, but few know what the process of recycling involves. This educational site (4) provides a good overview of aluminum, glass, plastic, and polycoat recycling. Brookhaven National Laboratory operates this page (5), which offers extensive information on its environmental research and technology focus areas. Some sections describe work in decontamination and decommissioning, waste form development, and risk assessment. On September 8, 2002, a news report reported that the air pollution in Hong Kong, which is notorious for poor air quality, reached an all-time high in August since monitoring began in 1995. Clear the Air (6) is a project that hopes to reverse this trend by introducing pollution control measures. The project's home page has information on the situation in Hong Kong, as well as facts about the risk of air pollution in general. Another news article (7) describes the recent construction of a computer shredding plant in Chicago. Since computer disposal is a major problem in the US, recycling this technological waste is increasingly important. The operation of the system is quite impressive. The Global Environment Centre Foundation's Environmental Technology Database (8) has specifications and documentation on many types of pollution control equipment and technologies. Much of the information is about Japanese applications.

Leske, Cavin.

2002-01-01

409

Metal pollution assessment of surface sediments along a new gas pipeline in the Niger Delta (Nigeria).  

PubMed

Chromium, nickel, copper, zinc and cadmium were determined in sediments of the Niger Delta (Nigeria) in order to discriminate between natural metal sources and anthropogenic ones. Surface sediments were collected at seven sites along a new gas pipeline near Port Harcourt, between the New Calabar River and the Bonny River towards Bonny town. Chemical characterisation is obtained by hydrofluoric-nitric acid digestion procedure, providing the 'total' ('residual') metal contents. Information about the anthropogenic metal fraction was obtained by cold diluted hydrochloric acid extraction procedure. This 'labile' acid soluble fraction of metals, perhaps due to relatively recent inputs in the sediments, constitutes the fraction more likely to be available to marine organisms, and furnishes a first evaluation of the possible toxicity of sediments of this sensitive ecosystem. Zinc appears to be the most available of all the heavy metals: its 'labile' fraction attains 40-50% of the 'total' zinc in sediment. Sites near Port Harcourt city are the most contaminated. All the examined metals are one order of magnitude below the respective values proposed as a limit for toxicity and are comparable with those observed by other authors in similar Niger Delta areas. Some anomalous data found near Port Harcourt city suggest that zinc and cadmium are the metals that require further monitoring. Their anthropogenic source could be derived from urban and industrial sewage. PMID:17219239

Adami, Gianpiero; Cabras, Igino; Predonzani, Sergio; Barbieri, Pierluigi; Reisenhofer, Edoardo

2007-02-01

410

Investigation of NOx Removal from Small Engine Exhaust  

NASA Technical Reports Server (NTRS)

Contribution of emissions from small engines to the air pollution is significant. Due to differences in operating conditions and economics, the pollution control systems designed for automobiles will be neither suitable nor economically feasible for use on small engines. The objective of this project was to find a catalyst for the removal of NOx from the exhaust of small engines which use a rich air to fuel ratio. The desired catalyst should be inexpensive so that the cost of the pollution control unit will be only a small fraction of the total equipment cost. The high cost of noble metals makes them too expensive for use as NOx catalyst for small engines. Catalytic reduction of Nitrogen Oxide (NO) can also be accomplished by base-metal oxide catalysts. The main disadvantage of base-metal catalysts is their deactivation by poisons and high temperatures. Requirements for the length of the life of the small engine exhaust catalysts are much less than those for automobile exhaust catalysts. Since there is no oxygen in the exhaust gases, reduction selectivity is not a problem. Also, the reducing exhaust gases might help prevent the harmful interactions of the catalyst with the support. For these reasons only the supported metal oxide catalysts were investigated in this project.

Akyurtlu, Ates; Akyurtlu, Jale F.

1999-01-01

411

Investigation of NO(x) Removal from Small Engine Exhaust  

NASA Technical Reports Server (NTRS)

Contribution of emissions from small engines to the air pollution is significant. Due to differences in operating conditions and economics, the pollution control systems designed for automobiles will be neither suitable nor economically feasible for use on small engines. The objective of this project was to find a catalyst for the removal of NOx from the exhaust of small engines which use a rich air to fuel ratio. The desired catalyst should be inexpensive so that the cost of the pollution control unit will be only a small fraction of the total equipment cost. The high cost of noble metals makes them too expensive for use as NOx catalyst for small engines. Catalytic reduction of NO can also be accomplished by base-metal oxide catalysts. The main disadvantage of base-metal catalysts is their deactivation by poisons and high temperatures. Requirements for the length of the life of the small engine exhaust catalysts are much less than those for automobile exhaust catalysts. Since there is no oxygen in the exhaust gases, reduction selectivity is not a problem. Also, the reducing exhaust gases might help prevent the harmful interactions of the catalyst with the support. For these reasons only the supported metal oxide catalysts were investigated in this project.

Akyurtlu, Ates; Akyurtlu, Jale F.

1999-01-01

412

Hypercholesterolemia potentiates aortic endothelial response to inhaled diesel exhaust  

PubMed Central

Background Inhalation of diesel exhaust induces vascular effects including impaired endothelial function and increased atherosclerosis. Objective To examine the in vivo effects of subchronic diesel exhaust exposure on endothelial cell transcriptional responses in the presence of hypercholesterolemia. Methods ApoE (?/?) and ApoE (+/+) mice inhaled diesel exhaust diluted to particulate matter levels of 300 or 1000 ?g/m3 vs. filtered air. After 30 days, endothelial cells were harvested from dispersed aortic cells by fluorescent-activated cell sorting (FACS). Relative mRNA abundance was evaluated by microarray analysis to measure strain-specific transcriptional responses in mice exposed to dilute diesel exhaust vs. filtered air. Results Forty-nine transcripts were significantly dysregulated by >2.8-fold in the endothelium of ApoE (?/?) mice receiving diesel exhaust at 300 or 1000 ?g/m3. These included transcripts with roles in plasminogen activation, endothelial permeability, inflammation, genomic stability, and atherosclerosis; similar responses were not observed in ApoE (+/+) mice. Conclusions The potentiation of diesel exhaust-related endothelial gene regulation by hypercholesterolemia helps to explain air pollution-induced vascular effects in animals and humans. The observed regulated transcripts implicate pathways important in the acceleration of atherosclerosis by air pollution. PMID:21222557

Maresh, J. Gregory; Campen, Matthew J.; Reed, Matthew D.; Darrow, April L.; Shohet, Ralph V.

2012-01-01

413

40 CFR 86.1823-01 - Durability demonstration procedures for exhaust emissions.  

Code of Federal Regulations, 2013 CFR

...General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle...exhaust emissions. This section applies to light-duty vehicles, light-duty...

2013-07-01

414

40 CFR 86.1823-01 - Durability demonstration procedures for exhaust emissions.  

Code of Federal Regulations, 2010 CFR

...General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle...exhaust emissions. This section applies to light-duty vehicles, light-duty...

2010-07-01

415

40 CFR 86.1823-01 - Durability demonstration procedures for exhaust emissions.  

Code of Federal Regulations, 2011 CFR

...General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle...exhaust emissions. This section applies to light-duty vehicles, light-duty...

2011-07-01

416

40 CFR 86.1823-01 - Durability demonstration procedures for exhaust emissions.  

Code of Federal Regulations, 2014 CFR

...General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle...exhaust emissions. This section applies to light-duty vehicles, light-duty...

2014-07-01

417

40 CFR 86.1823-01 - Durability demonstration procedures for exhaust emissions.  

Code of Federal Regulations, 2012 CFR

...General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle...exhaust emissions. This section applies to light-duty vehicles, light-duty...

2012-07-01

418

Exacerbation of allergic inflammation in mice exposed to diesel exhaust particles prior to viral infection.  

EPA Science Inventory

Background: Viral infections and exposure to oxidant air pollutants are two ofthe most important inducers ofasthma exacerbation. Our previous studies have demonstrated that exposure to diesel exhaust increases the susceptibility to influenza virus infections both in epithelial ce...

419

Diesel Exhaust Exposure and Nasal Response to Attenuated Influenza in Normal and Allergic Volunteers  

EPA Science Inventory

Rationale: Diesel exhaust enhances allergic inflammation, and pollutants are associated with heightened susceptibility to viral respiratory infections. The effects of combined diesel and virus exposure in humans are unknown. Objective: Test whether acute exposure to diesel modif...

420

40 CFR 600.510-12 - Calculation of average fuel economy and average carbon-related exhaust emissions.  

Code of Federal Regulations, 2014 CFR

...false Calculation of average fuel economy and average carbon-related exhaust emissions...CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR...Determining Manufacturer's Average Fuel Economy and Manufacturer's Average...

2014-07-01

421

40 CFR 600.510-12 - Calculation of average fuel economy and average carbon-related exhaust emissions.  

Code of Federal Regulations, 2013 CFR

...false Calculation of average fuel economy and average carbon-related exhaust emissions...CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR...Determining Manufacturer's Average Fuel Economy and Manufacturer's Average...

2013-07-01

422

40 CFR 600.510-12 - Calculation of average fuel economy and average carbon-related exhaust emissions.  

Code of Federal Regulations, 2012 CFR

... false Calculation of average fuel economy and average carbon-related exhaust emissions...AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF...Determining Manufacturer's Average Fuel Economy and Manufacturer's Average...

2012-07-01

423

Greenhouse gas aerosols and pollutants over Siberia: the YAK-AEROSIB French Russian Joint International Laboratory  

NASA Astrophysics Data System (ADS)

Despite the unique scientific value of better knowing atmospheric composition over Siberia, regional observations of the tropospheric composition over this region are still lacking. Large local anthropogenic emissions, strong ecosystem gas exchange across the vast forest expanse, and processes feeding back to global climate such as wetlands CH4 emissions, seabed hydrates destabilization and degrading permafrost make this region particularly crucial to investigate. We aim at addressing this need in the YAK-AEROSIB program by collecting high-precision in-situ measurements of the vertical distribution of CO2, CH4, CO, O3, black carbon and ultrafine particles distribution in the Siberian troposphere, as well as other parameters including aerosol lidar profiles, on a pan-Siberian aircraft transect. Campaigns are performed almost annually since 2006 until now on this regular route, while special campaigns are occasionnally arranged to sample the troposphere elsewere (e.g. Russian Arctic coast). We show the background tropospheric composition obtained from these surveys, the variability and the impact of large-scale transport of anthropogenic emissions from Europe and Asia, as well as the impact of biomass burning plumes both from local wildfires (2012) and from remote sources elsewhere in Asia. Long range transport of anthropogenic emissions is shown to have a discernible impact on O3 distribution, although its lower-tropospheric variability is largely driven by surface deposition. Regional sources and sinks drive the lower troposphere CO2 and CH4 concentrations. Recent efforts aim at better understanding the respective role of CH4 emission processes (including methanogenesis in wetlands and emissions by wildfires) in driving its large scale atmospheric variability over the region. Generally, the YAK AEROSIB provide unique observations over Siberia, documenting both direct impact of regional sources and aged air masses experiencing long range transport toward the high Arctic.

Paris, Jean-Daniel; Belan, Boris D.; Ancellet, Gérard; Nédélec, Philippe; Arshinov, Mikhail Yu.; Pruvost, Arnaud; Berchet, Antoine; Arzoumanian, Emmanuel; Pison, Isabelle; Ciais, Philippe; Law, Kathy

2014-05-01

424

PHYSIOLOGICAL, CELLULAR, AND BIOCHEMICAL EFFECTS OF DIESEL EXHAUST IN HEALTHY YOUNG ADULTS  

EPA Science Inventory

Diesel exhaust is a major source of pollution especially in urban areas. The contribution of the diesel exhaust particles and gases to increases in deaths, asthma symptoms, lung infections, and other health effects is unclear. This study will examine the lung, blood, heart, and o...

425

Investigation of turbine exhaust gas recirculation, base heating, and base pressure in the T-109 TsAGI wind tunnel for the IIAS ATLAS carrier model  

Microsoft Academic Search

Some quantitative data on gas recirculation in the carrier base region are presented which are obtained by measuring concentrations of chemical compounds and solving a set of equations for balance of chemical elements. The engine jets are simulated by solid fuel combustion products. The information concerning base region heating, base pressure and carrier surface pressure is also presented. The main

V. Neiland; A. Yereza; Y. Yermak; B. Zhirnikov; O. Kudin; Y. Leites; Y. Nesterov; V. Plyashechnik

1995-01-01

426

Air pollution.  

PubMed

Toxic air pollutants are continuously released into the air supply. Various pollutants come from chemical facilities and small businesses, such as automobile service stations and dry cleaning establishments. Others, such as nitrogen oxides, carbon monoxide and other volatile organic chemicals, arise primarily from the incomplete combustion of fossil fuels (coal and petroleum) and are emitted from sources that include car exhausts, home heating and industrial power plants. Pollutants in the atmosphere also result from photochemical transformations; for example, ozone is formed when molecular oxygen or nitrogen interacts with ultraviolet radiation. An association between air pollution exposure and lung cancer has been observed in several studies. The evidence for other cancers is far less conclusive. Estimates of the population attributable risk of cancer has varied substantially over the last 40 years, reflecting the limitations of studies; these include insufficient information on confounders, difficulties in characterizing associations due to a likely lengthy latency interval, and exposure misclassification. Although earlier estimates were less than one percent, recent cohort studies that have taken into account some confounding factors, such as smoking and education amongst others, suggest that approximately 3.6% of lung cancer in the European Union could be due to air pollution exposure, particularly to sulphate and fine particulates. A separate cohort study estimated 5-7% of lung cancers in European never smokers and ex-smokers could be due to air pollution exposure. Therefore, while cigarette smoking remains the predominant risk factor, the proportion of lung cancers attributable to air pollution may be higher than previously thought. Overall, major weaknesses in all air-pollution-and-cancer studies to date have been inadequate characterization of long-term air pollution exposure and imprecise or no measurements of covariates. It has only been in the last decade that measurements to PM2.5 become more widely available. A key weakness of many studies is using fixed-site monitoring data and assuming everyone in a region had the same exposure. This ignores spatial variability, and does not take into account how individuals' exposures differ with pollution sources inside, outside, both at work, home and elsewhere. More recent efforts to model indicators of vehicular traffic, and residential distances to major roads and highway can allow for some of this spatial variability to be better controlled for. However, this still does not take into account differences in activity patterns. If the effect is small, these biases will compromise the ability to detect an association. In most situations, the resulting estimates tend to be biased toward the null (i.e., no effect). For misclassification of exposure the inability to adequately control for confounding variables may cause bias in either direction. Recent improvements in statistical methodology use measurements at fixed sites combined with residential histories to estimate individuals' cumulative exposures. They also recognize measurement errors associated with covariates in the analysis to improve estimates of effects. Other challenges include the fact that measurements of exposure and confounders can change over time and long term data are needed due to the anticipated latency interval between harmful exposures and development of cancer. PMID:21199603

Le, Nhu D; Sun, Li; Zidek, James V

2010-01-01

427

Diesel exhaust rapidly degrades floral odours used by honeybees  

PubMed Central

Honeybees utilise floral odours when foraging for flowers; we investigated whether diesel exhaust pollution could interrupt these floral odour stimuli. A synthetic blend of eight floral chemicals, identified from oilseed rape, was exposed to diesel exhaust pollution. Within one minute of exposure the abundances of four of the chemicals were significantly lowered, with two components rendered undetectable. Honeybees were trained to recognise the full synthetic odour mix; altering the blend, by removing the two chemicals rendered undetectable, significantly reduced the ability of the trained honeybees to recognize the altered odour. Furthermore, we found that at environmentally relevant levels the mono-nitrogen oxide (NOx) fraction of the exhaust gases was a key facilitator of this odour degradation. Such changes in recognition may impact upon a honeybee's foraging efficiency and therefore the pollination services that they provide. PMID:24091789

Girling, Robbie D.; Lusebrink, Inka; Farthing, Emily; Newman, Tracey A.; Poppy, Guy M.

2013-01-01

428

DIESEL EXHAUST EXPOSURE INCREASES SEVERITY OF AN ONGOING INFLUENZA INFECTION  

EPA Science Inventory

Numerous studies have shown that air pollutants including diesel exhaust (DE) alter host defense responses, resulting in decreased resistance to respiratory infection. The purpose of this study was to evaluate the effects of DE exposure on the severity of an ongoing influenza in...

429

Acoustic Optimization of Automotive Exhaust Heat Thermoelectric Generator  

NASA Astrophysics Data System (ADS)

The potential for thermoelectric exhaust heat recovery in vehicles has been increasing with recent advances in the efficiency of thermoelectric generators (TEGs). This study analyzes the acoustic attenuation performance of exhaust-based TEGs. The acoustic characteristics of two different thermal designs of exhaust gas heat exchanger in TEGs are discussed in terms of transmission loss and acoustic insertion loss. GT-Power simulations and bench tests on a dynamometer with a high-performance production engine are carried out. Results indicate that the acoustic attenuation of TEGs could be determined and optimized. In addition, the feasibility of integration of exhaust-based TEGs and engine mufflers into the exhaust line is tested, which can help to reduce space and improve vehicle integration.

Su, C. Q.; Ye, B. Q.; Guo, X.; Hui, P.

2012-06-01

430

Quantitative planar laser-induced fluorescence imaging of multi-component fuel/air mixing in a firing gasoline-direct-injection engine: Effects of residual exhaust gas on quantitative PLIF  

SciTech Connect

A study of in-cylinder fuel-air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel-air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel-air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby 'bookend' calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for different fuel injection strategies. Finally, mixture distributions for late injection obtained using quantitative PLIF are compared to predictions of computational fluid dynamics calculations. (author)

Williams, Ben; Ewart, Paul [Department of Physics, Oxford University, Parks Road, Oxford OX1 3PU (United Kingdom); Wang, Xiaowei; Stone, Richard [Department of Engineering Science, Oxford University, Parks Road, Oxford OX1 3PJ (United Kingdom); Ma, Hongrui; Walmsley, Harold; Cracknell, Roger [Shell Global Solutions (UK), Shell Research Centre Thornton, P. O. Box 1, Chester, CH1 3SH (United Kingdom); Stevens, Robert; Richardson, David; Fu, Huiyu; Wallace, Stan [Jaguar Cars, Engineering Centre, Abbey Road, Whitley, Coventry, CV3 4LF (United Kingdom)

2010-10-15

431

Gas turbine alternative fuels combustion characteristics  

NASA Astrophysics Data System (ADS)

An experimental investigation was conducted to obtain combustion performance and exhaust pollutant concentrations for specific synthetic hydrocarbon fuels. Baseline comparison fuels used were gasoline and diesel fuel number two. Testing was done over a range of fuel to air mass ratios, total mass flow rates, and input combustion air temperatures in a flame-tube-type gas turbine combustor. Test results were obtained in terms of released heat and combustion gas emission values. The results were comparable to those obtained with the base fuels with variations being obtained with changing operating conditions. The release of carbon particles during the tests was minimal.

Rollbuhler, R. James

1989-02-01

432

Biological activity of particle exhaust emissions from light-duty diesel engines.  

PubMed

Whole diesel exhaust has been classified recently as a probable carcinogen, and several genotoxicity studies have found particulate exhaust to be clearly mutagenic. Moreover, genotoxicity of diesel particulate is greatly influenced by fuel nature and type of combustion. In order to obtain an effective environmental pollution control, combustion processes using alternative fuels are being analyzed presently. The goal of this study is to determine whether the installation of exhaust after treatment-devices on two light-duty, exhaust gas recirculation (EGR) valve-equipped diesel engines (1930 cc and 2500 cc) can reduce the mutagenicity associated with particles collected during U.S.A. and European driving cycles. Another interesting object was to compare the ability of alternative biodiesel and conventional diesel fuels to reduce the mutagenic activity associated with collected particles from two light duty diesel engines (both 1930 cc) during the European driving cycle. SOF mutagenicity was assayed using the Salmonella/microsome test (TA 98 and TA 100 strains, +/- S9 fraction). In the first part of our study, the highest mutagenicity was revealed by TA98 strain without enzymatic activation, suggesting a direct-acting mutagenicity prevalence in diesel particulate. The 2500 cc engine revealed twofold mutagenic activity compared with the 1930 cc engine (both EGR valve equipped), whereas an opposite result was found in particulate matter amount. The use of a noncatalytic ceramic trap produced a decrease of particle mutagenic activity in the 2500 cc car, whereas an enhancement in the 1930 cc engine was found. The catalytic converter and the electrostatic filter installed on the 2500 cc engine yielded a light particle amount and an SOF mutagenicity decrease. A greater engine stress was obtained using European driving cycles, which caused the strongest mutagenicity/km compared with the U.S.A. cycles. In the second part of the investigation, even though a small number of assays were available, exhaust emission generation by biodiesel fuel seemed to yield a smaller environmental impact than that of the referenced diesel fuel. The results point out the usefulness of mutagenicity testing in the research of both newer, more efficient automotive aftertreatment devices and less polluting fuels. PMID:9275990

Carraro, E; Locatelli, A L; Ferrero, C; Fea, E; Gilli, G

1997-01-01

433

Volatile organic compounds from the exhaust of light-duty diesel vehicles  

NASA Astrophysics Data System (ADS)

The exhaust gas constituents of light-duty diesel vehicles (LDDVs), including total hydrocarbon (THC), non-methane hydrocarbon (NMHC), carbon monoxide (CO), nitrogen oxide (NOx), and volatile organic compounds (VOCs) were measured by a dynamometer study following federal test procedure-75 (FTP-75) and highway fuel economy cycle. The average fuel consumption of these LDDVs was 0.126 L km-1 for FTP-75, with about 10% fuel consumption savings for highway driving. The average emission factors of NMHC, CO and NOx for light-duty vehicles were 0.158/0.132 (90% of THC), 1.395/1.138, and 1.735/1.907 g km-1 for FTP-75/Highway, respectively. Styrene, n-propylbenzene, n-undecane, o-ethyltoluene, 1,2,4-trimethylbenzene, toluene, o-xylene, isopropylbenzene, m,p-xylene, and ethylbenzene were the dominant VOCs of LDDV exhaust, and the emission factors were about 10-60 mg kg-1. In addition, formaldehyde, acetaldehyde, acetone, butyraldehyde, and m-tolualdehyde were the major carbonyl species from LDDV exhaust, and the emission factors ranged from 1 to 10 mg km-1. The ozone formation potentials of m,p-xylene, o-ethyltoluene, 1,2,4-trimethylbenzene, o-xylene, n-propylbenzene, styrene, and isoprene were >50 mg-O3 km-1. In addition, formaldehyde, acetaldehyde, and butyraldehyde revealed high ozone formation potential of carbonyl species, with values ranging from 10 to 95 mg-O3 km-1. Based on the exhaust constituents and ozone formation potential observed, diesel vehicles could be an important air pollution source for urban and industrial areas.

Tsai, Jiun-Horng; Chang, Sheng-You; Chiang, Hung-Lung

2012-12-01

434

On-Road Measurement of Exhaust Emission Factors for Individual Diesel Trucks  

NASA Astrophysics Data System (ADS)

Diesel trucks are an important source of primary fine particulate matter (PM2.5) that includes black carbon (BC) as a major component. More stringent exhaust emission standards for new engines, effective starting in 2007, considerably reduce allowable emissions and have led to use of after-treatment control devices such as diesel particle filters. The state of California is also implementing programs to accelerate replacement or retrofit of older trucks. In light of these changes, measurements of emissions from in-use heavy-duty diesel trucks are timely and needed to understand the impact of new control technologies on emissions. PM2.5, BC mass, particle light absorption, and particle light extinction emission factors for hundreds of individual diesel trucks were measured in this study. Emissions were measured in July 2010 from trucks driving through the Caldecott tunnel in the San Francisco Bay area. Gas-phase emissions including nitric oxide, nitrogen dioxide, carbon monoxide, and carbon dioxide (CO2) were also measured. Pollutants were measured using air sampling inlets located directly above the vertical exhaust stacks of heavy-duty trucks driving by on the roadway below. All of these measurements were made using fast time response (1 Hz) sensors. Particle optical properties were simultaneously characterized with direct measurements of absorption (babs) and extinction (bext) coefficients. Emission factors for individual trucks were calculated using a carbon balance method in which emissions of PM2.5, BC, babs, and bext in each exhaust plume were normalized to emissions of CO2. Emission factor distributions and fleet-average values are quantified. Absorption and extinction emission factors are used to calculate the aerosol single scattering albedo and BC mass absorption efficiency for individual truck exhaust plumes.

Dallmann, T. R.; DeMartini, S.; Harley, R. A.; Kirchstetter, T. W.; Wood, E. C.; Onasch, T. B.; Herndon, S. C.

2011-12-01

435

Technical Note: The application of an improved gas and aerosol collector for ambient air pollutants in China  

NASA Astrophysics Data System (ADS)

An improved Gas and Aerosol Collector (GAC) equipped with a newly designed aerosol collector and a set of dull-polished wet annular denuder (WAD) was developed based on a Steam Jet Aerosol Collector (SJAC) sampler. Combined with Ion Chromatography (IC) the new sampler performed well in laboratory tests with high collection efficiencies for SO2 (above 98%) and particulate sulfate (as high as 99.5%). When applied in two major field campaigns (rural and coastal sites) in China, the GAC-IC system provided high-quality data in ambient conditions even under high loadings of pollutants. Its measurements were highly correlated with data by other commercial instruments such as the SO2 analyzer (43c, Thermo-Fisher, USA; R2 as 0.96), the HONO analyzer (LOPAP, Germany; R2 as 0.91 for nighttime samples), a filter sampler (Tianhong, China; R2 as 0.86 for SO42-), and Aerosol Mass Spectrometer (AMS, Aerodyne, USA; R2 above 0.77 for major species) over a wide range of concentrations. Through the application of the GAC-IC system, it was identified that 70% of chloride and nitrate by the filter method could be lost during daytime sampling due to high temperature in the rural site of Kaiping. In Changdao field campaign (coastal site) the comparison with the measurements by the GAC-IC suggested that the collection efficiency of AMS might be greatly influenced by high relative humidity (RH) especially in coastal or marine environment. Through laboratory and field studies, this instrument is proved highly reliable, which is particularly useful in future intensive campaigns or long-term monitoring stations to study various environmental issues such as secondary aerosol and haze formation, as well as climate change.

Dong, H.-B.; Zeng, L.-M.; Hu, M.; Wu, Y.-S.; Zhang, Y.-H.; Slanina, J.; Zheng, M.; Wang, Z.-F.; Jansen, R.

2012-03-01

436

Updated greenhouse gas and criteria air pollutant emission factors and their probability distribution functions for electricity generating units  

SciTech Connect

Greenhouse gas (CO{sub 2}, CH{sub 4} and N{sub 2}O, hereinafter GHG) and criteria air pollutant (CO, NO{sub x}, VOC, PM{sub 10}, PM{sub 2.5} and SO{sub x}, hereinafter CAP) emission factors for various types of power plants burning various fuels with different technologies are important upstream parameters for estimating life-cycle emissions associated with alternative vehicle/fuel systems in the transportation sector, especially electric vehicles. The emission factors are typically expressed in grams of GHG or CAP per kWh of electricity generated by a specific power generation technology. This document describes our approach for updating and expanding GHG and CAP emission factors in the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model developed at Argonne National Laboratory (see Wang 1999 and the GREET website at http://greet.es.anl.gov/main) for various power generation technologies. These GHG and CAP emissions are used to estimate the impact of electricity use by stationary and transportation applications on their fuel-cycle emissions. The electricity generation mixes and the fuel shares attributable to various combustion technologies at the national, regional and state levels are also updated in this document. The energy conversion efficiencies of electric generating units (EGUs) by fuel type and combustion technology are calculated on the basis of the lower heating values of each fuel, to be consistent with the basis used in GREET for transportation fuels. On the basis of the updated GHG and CAP emission factors and energy efficiencies of EGUs, the probability distribution functions (PDFs), which are functions that describe the relative likelihood for the emission factors and energy efficiencies as random variables to take on a given value by the integral of their own probability distributions, are updated using best-fit statistical curves to characterize the uncertainties associated with GHG and CAP emissions in life-cycle modeling with GREET.

Cai, H.; Wang, M.; Elgowainy, A.; Han, J. (Energy Systems)

2012-07-06

437

GAS-PHASE MASS TRANSFER MODEL FOR PREDICTING VOLATILE ORGANIC COMPOUND (VOC) EMISSION RATES FROM INDOOR POLLUTANT SOURCES  

EPA Science Inventory

Analysis of the impact of sources on indoor pollutant concentrations and occupant exposure to indoor pollutants requires knowledge of the emission rates from the sources. Emission rates are often determined by chamber testing and the data from the chamber test are fitted to an em...

438

A Flight Investigation of Exhaust-heat De-icing  

NASA Technical Reports Server (NTRS)

The National Advisory Committee for Aeronautics conducted exhaust-heat de-icing tests in flight to provide data needed in the application of this method. The capacity to extract heat from the exhaust gas for de-icing purposes, the quantity of heat required, and other factors were examined. The results indicate that a wing-heating system employing a spanwise exhaust tube within the leading edge of the wing removed 30 to 35 percent of the heat from exhaust gas entering the wing. Data are given from which the heat required for ice prevention can be calculated. Sample calculations have been made on the basis of existing engine power/wing area ratios to show that sufficient heating can be obtained for ice protection on modern transportation airplanes, provided that uniform distribution of the heat can be secured.

Jones, Alun R; Rodert, Lewis A

1940-01-01

439

Validation of scramjet exhaust simulation technique at Mach 6  

NASA Technical Reports Server (NTRS)

Current design philosophy for hydrogen-fueled, scramjet-powered hypersonic aircraft results in configurations with strong couplings between the engine plume and vehicle aerodynamics. The experimental verification of the scramjet exhaust simulation is described. The scramjet exhaust was reproduced for the Mach 6 flight condition by the detonation tube simulator. The exhaust flow pressure profiles, and to a large extent the heat transfer rate profiles, were then duplicated by cool gas mixtures of Argon and Freon 13B1 or Freon 12. The results of these experiments indicate that a cool gas simulation of the hot scramjet exhaust is a viable simulation technique except for phenomena which are dependent on the wall temperature relative to flow temperature.

Hopkins, H. B.; Konopka, W.; Leng, J.

1979-01-01

440

Soot filter for an exhaust arrangement of an internal combustion engine  

Microsoft Academic Search

A soot filter arrangement for an exhaust gas flow of an internal combustion engine, especially an air-compressing internal combustion engine. The filter arrangement includes a housing with feed and discharge connections for the exhaust gas stream in a mineral filter material arranged in the housing. The material is provided on a support pipe equipped with passage openings which enable the

H. Bergmann; H. Daudel; H. Erdmannsdorfer

1982-01-01

441

Investigation of turbine exhaust gas recirculation, base heating, and base pressure in the T-109 TsAGI wind tunnel for the IIAS ATLAS carrier model  

NASA Astrophysics Data System (ADS)

Some quantitative data on gas recirculation in the carrier base region are presented which are obtained by measuring concentrations of chemical compounds and solving a set of equations for balance of chemical elements. The engine jets are simulated by solid fuel combustion products. The information concerning base region heating, base pressure and carrier surface pressure is also presented. The main objective of the investigation carried out is to identify the contribution of different sources to filling the IIAS ATLAS carrier model base region with gases. Four possible sources are considered; the central unit comprising one sustainer and two side liquid boosters, solid-rocket boosters, the turbopump assemblies and the free-stream flow.

Neiland, V.; Yereza, A.; Yermak, Y.; Zhirnikov, B.; Kudin, O.; Leites, Y.; Nesterov, Y.; Plyashechnik, V.

442

Apparatus for cleaning blast-furnace exhaust gases  

Microsoft Academic Search

An apparatus for cleaning the exhaust gas of a high-pressure blast furnace comprises a coarse-particle separator, a prewasher and a differential-pressure annular gap washer traversed in succession by the gases. The exhaust gases can be passed through a main duct provided with an expansion turbine or through a bypass duct around the expansion turbine. The expansion turbine unit controls the

K. R. Hegemann; G. Finger; A. Brinkmann; H. Weissert

1977-01-01

443

Design and application of a mobile ground-based observatory for continuous measurements of atmospheric trace-gas and criteria pollutant species  

NASA Astrophysics Data System (ADS)

Ground-based measurements of atmospheric trace gas species and criteria pollutants are essential for understanding emissions dynamics across space and time. Gas composition in the surface 50 m has the greatest direct impacts on human health as well as ecosystem processes, hence data at this level is necessary for addressing carbon cycle and public health related questions. However, such surface data are generally associated with stationary measurement towers, where spatial representation is limited due to the high cost of establishing and maintaining an extensive network of measurement stations. We describe here a compact mobile laboratory equipped to provide high-precision, high-frequency, continuous, on-road synchronous measurements of CO2, CO, CH4, H2O, NOx, O3, aerosol, meteorological, and geospatial position data. The mobile laboratory has been deployed across the western USA. In addition to describing the vehicle and its capacity, we present data that illustrate the use of the laboratory as a powerful tool for investigating the spatial structure of urban trace gas emissions and criteria pollutants at spatial scales ranging from single streets to whole ecosystem and regional scales. We identify fugitive urban CH4 emissions and assess the magnitude of CH4 emissions from known point sources. We illustrate how such a mobile laboratory can be used to better understand emissions dynamics and quantify emissions ratios associated with trace gas emissions from wildfire incidents. Lastly, we discuss additional mobile laboratory applications in health and urban metabolism.

Bush, S. E.; Hopkins, F. M.; Randerson, J. T.; Lai, C.-T.; Ehleringer, J. R.

2015-01-01

444

Recent advances in investigations of toxicity of automotive exhaust.  

PubMed

The influence of auto exhaust on man's health is difficult to gauge considering the intricacy of human environmental urban stresses and particularly of other air polluting (industrial, domestic) emissions. Epidemiological surveys made in road tunnel employees and in traffic officers have not demonstrated specific effects and have often been complicated by cigarette smoking as a factor. Long-term animal experiments run mostly on small rodents give evidence of little effect of the pathological actions of dilutions such as those encountered in high polluted cities. However the acute toxicity of gasoline exhaust emission is well known and mostly due to carbon monoxide. Considering the different types of cycles and operating conditions of vehicles (gasoline and diesel), auto exhaust gases constitute no more a chemical entity than they show, a definite toxicity. A great number of substances that they contain (nitrogen oxides, aldehydes, antiknock additives, heavy metals, possible catalysts are highly toxic as shown by in vivo and in vitro (mutagenic) tests. Interactions of the components are for the moment ignored or poorly understood. Besides, the evolution of the physicochemical properties and natures of the auto exhaust emission in the gaseous biotope of man under determined conditions of ultraviolet irradiation, temperature, and hygrometry provoke the formation of secondary products such as oxidants and ozone. Several experiments show clearly that irradiation increases the toxicity of auto exhaust significantly. For these reasons, geographical, meteorological, and chronological (circadian and seasonal) factors should be taken into consideration, especially with regard to emission standards. PMID:67944

Stupfel, M

1976-10-01

445

AEROJET: nonintrusive measurements of aircraft engine exhaust emissions  

Microsoft Academic Search

The environment impact of air traffic and economical aspects require aircraft engines to be developed which have reduced trace gas emissions and, at the same time, increased efficiency. Each new engine must be shown to meet the environmental requirements laid down by regulatory bodies, and exhaust gas measurements must be performed for the certification. The goal of the EC project

Klaus Schaefer; Joerg Heland; Roger Burrows; John D. Black; Marc Bernard; Gary Bishop; Volker Tank; Erwin Lindermeir; Dave H. Lister; Robert S. Falk; Peter Wiesen; Moira Hilton

1997-01-01

446

Macro-kinetic investigation on phenol uptake from air by biofiltration: Influence of superficial gas flow rate and inlet pollutant concentration  

SciTech Connect

The macro-kinetic behavior of phenol removal from a synthetic exhaust gas was investigated theoretically as well as experimentally by means of two identical continuously operating laboratory-scale biological filter bed columns. A mixture of peat and glass beads was used as filter material. After sterilization it was inoculated with a pure strain of Pseudomonas putida, as employed in previous experimental studies. To determine the influence of the superficial gas flow rate on biofilter performance and to evaluate the phenol concentration profiles along the column, two series of continuous tests were carried out varying either the inlet phenol concentration, up to 1,650 mg {center_dot} m{sup {minus}3}, or the superficial gas flow rate, from 30 to 460 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}. The elimination capacity of the biofilter is proved by a maximum volumetric phenol removal rate of 0.73 kg {center_dot} m{sup {minus}3} {center_dot} h{sup {minus}1}. The experimental results are consistent with a biofilm model incorporating first-order substrate elimination kinetics. The model may be considered a useful tool in scaling-up a biofiltration system. Furthermore, the deodorization capacity of the biofilter was investigated, at inlet phenol concentrations up to 280 mg {center_dot} m{sup {minus}3} and superficial gas flow rates ranging from 30 to 92 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}. The deodorization of the gas was achieved at a maximum inlet phenol concentration of about 255 mg {center_dot} m{sup {minus}3}, operating at a superficial gas flow rate of 30 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}.

Zilli, M.; Fabiano, B.; Ferraiolo, A.; Converti, A. [Genoa Univ., Genova (Italy). Inst. of Chemical and Process Engineering] [Genoa Univ., Genova (Italy). Inst. of Chemical and Process Engineering

1996-02-20

447

Detection of mutagenic activity in automobile exhaust.  

PubMed

Using the Ames Salmonella-microsome system, we detected mutagenic activity in the exhaust from two kinds of 4-cycle gasoline engines of unregulated and regulated cars, and from diesel engines, as well as in the particulates from air collected in tunnels. The mutagenicity of particulates from a car equipped with a catalyst (regulated car), as compared with that from an unregulated car, was reduced very much (down to 500 from 4500 revertants/plate/m3 in tester strain TA98). However, the mutagenicity of the ether-soluble acid and neutral fractions from the condensed water of emissions from a regulated car was still high (down to 2880 from 10 900 revertants/plate/m3 in tester strain TA100). The mutagenic activity of emission exhaust from old diesel car engines was very high; the particulates showed 9140 and 19 600 revertants/plate/m3 from strain TA98 incubated with an activating rat-liver S9 fraction. A small diesel engine of the type used for the generation of electric power or in farm machinery also produced exhaust with highly mutagenic particulates. The mutagenic activity of a methanol extract of particulate air pollutants collected in a highway tunnel showed 39 revertants/plate/m3 toward strain TA98 and 87 toward strain TA100. The ether-soluble neutral fraction yielded 86 revertants/plate/m3 from strain TA98 and 100 from strain TA100. This fraction also contained carcinogenic compounds, including benzo[a]pyrene, benzo[e]pyrene, benz[a]anthracene, benzo[ghi]perylene and chrysene. Very high mutagenic activity was detected, especially in the particulate air pollutants collected at night, in another tunnel on a superhighway: 60-88 revertants/plate/m3 from strain TA100 for the sample collected by day, but 121-238, by night. Night traffic includes many more diesel-powered vehicles compared with gasoline-powered automobiles. PMID:6155611

Ohnishi, Y; Kachi, K; Sato, K; Tahara, I; Takeyoshi, H; Tokiwa, H

1980-03-01

448

US Department of Energy - Office of FreedomCar and Vehicle Technologies and US Centers for Disease Control and Prevention - National Institute for Occupational Safety and Health Inter-Agency Agreement Research on "The Analysis of Genotoxic Activities of Exhaust Emissions from Mobile Natural Gas, Diesel, and Spark-Ignition Engines"  

SciTech Connect

The US Department of Energy-Office of Heavy Vehicle Technologies (now the DOE-Office of FreedomCar and Vehicle Technologies) signed an Interagency Agreement (IAA) with National Institute for Occupational Safety and Health (NIOSH), No.01-15 DOE, 9/4/01, for 'The analysis of genotoxic activities of exhaust emissions from mobile natural gas, diesel, and spark-ignition engines'; subsequently modified on 3/27/02 (DOE IAG No.01-15-02M1); subsequently modified 9/02/03 (IAA Mod No. 01-15-03M1), as 'The analysis of genotoxic activities of exhaust emissions from mobile internal combustion engines: identification of engine design and operational parameters controlling exhaust genotoxicity'. The DOE Award/Contract number was DE-AI26-01CH11089. The IAA ended 9/30/06. This is the final summary technical report of National Institute for Occupational Safety and Health research performed with the US Department of Energy-Office of FreedomCar and Vehicle Technologies under that IAA: (A) NIOSH participation was requested by the DOE to provide in vitro genotoxicity assays of the organic solvent extracts of exhaust emissions from a suite of in-use diesel or spark-ignition vehicles; (B) research also was directed to develop and apply genotoxicity assays to the particulate phase of diesel exhaust, exploiting the NIOSH finding of genotoxicity expression by diesel exhaust particulate matter dispersed into the primary components of the surfactant coating the surface of the deep lung; (C) from the surfactant-dispersed DPM genotoxicity findings, the need for direct collection of DPM aerosols into surfactant for bioassay was recognized, and design and developmental testing of such samplers was initiated.

William E. Wallace

2006-09-30

449

The National Environmental Respiratory Center (NERC) experiment in multi-pollutant air quality health research: II. Comparison of responses to diesel and gasoline engine exhausts, hardwood smoke and simulated downwind coal emissions.  

PubMed

The NERC Program conducted identically designed exposure-response studies of the respiratory and cardiovascular responses of rodents exposed by inhalation for up to 6 months to diesel and gasoline exhausts (DE, GE), wood smoke (WS) and simulated downwind coal emissions (CE). Concentrations of the four combustion-derived mixtures ranged from near upper bound plausible to common occupational and environmental hotspot levels. An "exposure effect" statistic was created to compare the strengths of exposure-response relationships and adjustments were made to minimize false positives among the large number of comparisons. All four exposures caused statistically significant effects. No exposure caused overt illness, neutrophilic lung inflammation, increased circulating micronuclei or histopathology of major organs visible by light microscopy. DE and GE caused the greatest lung cytotoxicity. WS elicited the most responses in lung lavage fluid. All exposures reduced oxidant production by unstimulated alveolar macrophages, but only GE suppressed stimulated macrophages. Only DE retarded clearance of bacteria from the lung. DE before antigen challenge suppressed responses of allergic mice. CE tended to amplify allergic responses regardless of exposure order. GE and DE induced oxidant stress and pro-atherosclerotic responses in aorta; WS and CE had no such effects. No overall ranking of toxicity was plausible. The ranking of exposures by number of significant responses varied among the response models, with each of the four causing the most responses for at least one model. Each exposure could also be deemed most or least toxic depending on the exposure metric used for comparison. The database is available for additional analyses. PMID:25162719

Mauderly, J L; Barrett, E G; Day, K C; Gigliotti, A P; McDonald, J D; Harrod, K S; Lund, A K; Reed, M D; Seagrave, J C; Campen, M J; Seilkop, S K

2014-09-01

450

Technical Note: The application of an improved gas and aerosol collector for ambient air pollutants in China  

NASA Astrophysics Data System (ADS)

An improved Gas and Aerosol Collector (GAC) equipped with a newly designed aerosol collector and a set of dull-polished wet annular denuder (WAD) was developed based on a Steam Jet Aerosol Collector (SJAC) sampler. Combined with Ion Chromatography (IC) the new sampler performed well in laboratory tests with high collection efficiencies for SO2 (above 98%) and particulate sulfate (as high as 99.5%). An inter-comparison between the GAC-IC system and the filter-pack method was performed and the results indicated that the GAC-IC system could supply reliable particulate sulfate, nitrate, chloride, and ammonium data in field measurement with a much wider range of ambient concentrations. When applied in two major field campaigns (rural and coastal sites) in China, the GAC-IC system provided high-quality data in ambient conditions even under high loadings of pollutants. Its measurements were highly correlated with data by other commercial instruments such as the SO2 analyzer (43c, Thermo-Fisher, USA; R2 as 0.96), the HONO analyzer (LOPAP, Germany; R2 as 0.91 for samples from 15:00 to 07:00), a filter sampler (Tianhong, China; R2 as 0.86 for SO42-), and Aerosol Mass Spectrometer (AMS, Aerodyne, USA; R2 above 0.77 for major species) over a wide range of concentrations. Through the application of the GAC-IC system, it was identified that 70% of chloride and nitrate by the filter method could be lost during daytime sampling due to high temperature in the rural site of Kaiping. In Changdao field campaign (coastal site), though a particle dryer was applied, its drying efficiency was not well considered for the collection efficiency of AMS seemed still interfered a bit by local high relative humidity. If the inter-comparison was done with relative humidity below 50%, the correlations ranged from 0.81 to 0.94 for major species. Through laboratory and field studies, this instrument is proved particularly useful in future intensive campaigns or long-term monitoring stations to study various environmental issues such as secondary aerosol and haze formation, as well as climate change.

Dong, H.-B.; Zeng, L.-M.; Hu, M.; Wu, Y.-S.; Zhang, Y.-H.; Slanina, J.; Zheng, M.; Wang, Z.-F.; Jansen, R.

2012-11-01

451

Understanding high wintertime ozone pollution events in an oil- and natural gas-producing region of the western US  

NASA Astrophysics Data System (ADS)

Recent increases in oil and natural gas (NG) production throughout the western US have come with scientific and public interest in emission rates, air quality and climate impacts related to this industry. This study uses a regional-scale air quality model (WRF-Chem) to simulate high ozone (O3) episodes during the winter of 2013 over the Uinta Basin (UB) in northeastern Utah, which is densely populated by thousands of oil and NG wells. The high-resolution meteorological simulations are able qualitatively to reproduce the wintertime cold pool conditions that occurred in 2013, allowing the model to reproduce the observed multi-day buildup of atmospheric pollutants and the accompanying rapid photochemical ozone formation in the UB. Two different emission scenarios for the oil and NG sector were employed in this study. The first emission scenario (bottom-up) was based on the US Environmental Protection Agency (EPA) National Emission Inventory (NEI) (2011, version 1) for the oil and NG sector for the UB. The second emission scenario (top-down) was based on estimates of methane (CH4) emissions derived from in situ aircraft measurements and a regression analysis for multiple species relative to CH4 concentration measurements in the UB. Evaluation of the model results shows greater underestimates of CH4 and other volatile organic compounds (VOCs) in the simulation with the NEI-2011 inventory than in the case when the top-down emission scenario was used. Unlike VOCs, the NEI-2011 inventory significantly overestimates the emissions of nitrogen oxides (NOx), while the top-down emission scenario results in a moderate negative bias. The model simulation using the top-down emission case captures the buildup and afternoon peaks observed during high O3 episodes. In contrast, the simulation using the bottom-up inventory is not able to reproduce any of the observed high O3 concentrations in the UB. Simple emission reduction scenarios show that O3 production is VOC sensitive and NOx insensitive within the UB. The model results show a disproportionate contribution of aromatic VOCs to O3 formation relative to all other VOC emissions. The model analysis reveals that the major factors driving high wintertime O3 in the UB are shallow boundary layers with light winds, high emissions of VOCs from oil and NG operations compared to NOx emissions, enhancement of photolysis fluxes and reduction of O3 loss from deposition due to snow cover.

Ahmadov, R.; McKeen, S.; Trainer, M.; Banta, R.; Brewer, A.; Brown, S.; Edwards, P. M.; de Gouw, J. A.; Frost, G. J.; Gilman, J.; Helmig, D.; Johnson, B.; Karion, A.; Koss, A.; Langford, A.; Lerner, B.; Olson, J.; Oltmans, S.; Peischl, J.; Pétron, G.; Pichugina, Y.; Roberts, J. M.; Ryerson, T.; Schnell, R.; Senff, C.; Sweeney, C.; Thompson, C.; Veres, P. R.; Warneke, C.; Wild, R.; Williams, E. J.; Yuan, B.; Zamora, R.

2015-01-01

452

Nonparticulate Components of Diesel Exhaust Promote Constriction in Coronary Arteries from ApoE-\\/- Mice  

Microsoft Academic Search

Air pollution is positively associated with increased daily incidence of myocardial infarction and cardiovascular mortality. We hypothesize that air pollutants, primarily vapor phase organic compounds, cause an enhancement of coronary vascular constric- tion. Such events may predispose susceptible individuals to anginal symptoms and\\/or exacerbation of infarction. To develop this hypothesis, we studied the effects of nonparticulate diesel exhaust constituents on

Matthew J. Campen; N. Sathish Babu; G. Andrew Helms; Stuart Pett; Jorge Wernly; Reza Mehran; Jacob D. McDonald

2005-01-01

453

Determination of naval medium speed diesel engine air exhaust emissions and validation of a proposed estimation model. Master`s thesis  

SciTech Connect

Steady state marine diesel engine exhaust emissions are being reviewed by the Environmental Protection Agency for possible regulation. In anticipation of future regulation, the United States Navy is developing appropriate emissions models for naval vessels. A procedure for collecting this data from an U. S. Navy ship with medium speed main propulsion diesels is presented. It is based on similar testing conducted by the U.S. Coast Guard for measuring patrol boat diesel engine emissions and International Standards Organization methodology. The primary challenge of the experiment design was to minimize interference with the engineering plant as the assigned ship was concurrently tasked for other operations. Data gathered allowed calculation of engine rpm, engine load, exhaust gas flow rate, and determination of pollutant amounts. The tests were conducted at a series of predetermined speeds to reflect an 11-Mode duty cycle developed previously for the LSD 41 Class propulsion diesel engines.

Mayeaux, A.M.

1995-05-01

454

Understanding high wintertime ozone pollution events in an oil and natural gas producing region of the western US  

NASA Astrophysics Data System (ADS)

Recent increases in oil and natural gas (NG) production throughout the western US have come with scientific and public interest in emission rates, air quality and climate impacts related to this industry. This study uses a regional scale air quality model WRF-Chem to simulate high ozone (O3) episodes during the winter of 2013 over the Uinta Basin (UB) in northeastern Utah, which is densely populated by thousands of oil and NG wells. The high resolution meteorological simulations are able to qualitatively reproduce the wintertime cold pool conditions that occurred in 2013, allowing the model to reproduce the observed multi-day buildup of atmospheric pollutants and accompanying rapid photochemical ozone formation in the UB. Two different emission scenarios for the oil and NG sector were employed in this study. The first emission scenario (bottom-up) was based on the US EPA National Emission Inventory (NEI) (2011, version 1) for the oil and NG sector for the UB. The second emission scenario (top-down) was based on the previously derived estimates of methane (CH4) emissions and a regression analysis for multiple species relative to CH4 concentration measurements in the UB. WRF-Chem simulations using the two emission data sets resulted in significant differences for concentrations of most gas-phase species. Evaluation of the model results shows greater underestimates of CH4 and other volatile organic compounds (VOCs) in the simulation with the NEI-2011 inventory than the case when the top-down emission scenario was used. Unlike VOCs, the NEI-2011 inventory significantly overestimates the emissions of nitrogen oxides (NOx), while the top-down emission scenario results in a moderate negative bias. Comparison of simulations using the two emission data sets reveals that the top-down case captures the high O3 episodes. In contrast, the simulation case using the bottom-up inventory is not able to reproduce any of the observed high O3 concentrations in the UB. A sensitivity analysis reveals that the major factors driving high wintertime O3 in the UB are shallow boundary layers with light winds, high emissions of VOCs from oil and NG operations compared to NOx emissions, enhancement of photolysis fluxes and reduction of O3 loss from deposition due to snow cover. Simple emission reduction scenarios show that the UB O3 production is VOC sensitive and NOx insensitive. The model results show a disproportionate contribution of aromatic VOCs to O3 formation relative to all other VOC emissions. We also present modeling results for winter of 2012, when high O3 levels were not observed in the UB. The air quality model together with the top-down emission framework presented here may help to address the emerging science and policy related questions surrounding the environmental impact of oil and NG drilling in western US.

Ahmadov, R.; McKeen, S.; Trainer, M.; Banta, R.; Brewer, A.; Brown, S.; Edwards, P. M.; de Gouw, J. A.; Frost, G. J.; Gilman, J.; Helmig, D.; Johnson, B.; Karion, A.; Koss, A.; Langford, A.; Lerner, B.; Olson, J.; Oltmans, S.; Peischl, J.; Pétron, G.; Pichugina, Y.; Roberts, J. M.; Ryerson, T.; Schnell, R.; Senff, C.; Sweeney, C.; Thompson, C.; Veres, P.; Warneke, C.; Wild, R.; Williams, E. J.; Yuan, B.; Zamora, R.

2014-08-01

455

Characterization of nitromethane emission from automotive exhaust  

NASA Astrophysics Data System (ADS)

We carried out time-resolved experiments using a proton-transfer-reaction mass spectrometer and a chassis dynamometer to characterize nitromethane emission from automotive exhaust. We performed experiments under both cold-start and hot-start conditions, and determined the dependence of nitromethane emission on vehicle velocity and acceleration/deceleration as well as the effect of various types of exhaust-gas treatment system. We found that nitromethane emission was much lower from a gasoline car than from diesel trucks, probably due to the reduction function of the three-way catalyst of the gasoline car. Diesel trucks without a NOx reduction catalyst using hydrocarbons produced high emissions of nitromethane, with emission factors generally increasing with increasing acceleration at low vehicle velocities.

Sekimoto, Kanako; Inomata, Satoshi; Tanimoto, Hiroshi; Fushimi, Akihiro; Fujitani, Yuji; Sato, Kei; Yamada, Hiroyuki

2013-12-01

456

Gasdynamic propagation of rocket exhaust products in the upper atmosphere  

NASA Astrophysics Data System (ADS)

The dispersion of exhaust products of rocket fuel in the direction perpendicular to the motion of a rocket is investigated in this work. A comparison of the results of numerical calculations with a self-similar approximation of a strong cylindrically symmetric explosion is fulfilled. It is shown that at sufficiently high rocket velocity V ?, which exceeds the sum of gas exhaust velocity V e from the nozzle and sound speed V s ( V ? > V e + V s ), a gasdynamic hole can arise around the rocket trajectory in the upper atmosphere, inside which the total concentration of gas becomes less than the equilibrium concentration of gas at a given altitude. The dynamics of the profiles of density and temperature of the exhaust products inside a rocket plume is calculated.

Molchanov, A. G.; Platov, Yu. V.

2011-12-01

457

A Method for Reducing the Temperature of Exhaust Manifolds  

NASA Technical Reports Server (NTRS)

This report describes tests conducted at the Langley Memorial Aeronautical Laboratory on an "air-inducting" exhaust manifold for aircraft engines. The exhaust gases from each cylinder port are discharged into the throat of an exhaust pipe which has a frontal bellmouth. Cooling air is drawn into the pipe, where it surrounds and mixes with the exhaust gases. Temperatures of the manifold shell and of the exhaust gases were obtained in flight for both a conventional manifold and the air-inducting manifold. The air-inducting manifold was installed on an engine which was placed on a test stand. Different fuels were sprayed on and into the manifold to determine whether the use of this manifold reduced the fire hazard. The flight tests showed reductions in manifold temperatures of several hundred degrees, to values below the ignition point of aviation gasoline. On the test stand when the engine was run at idling speeds fuels sprayed into the manifold ignited. It is believed that at low engine speeds the fuel remained in the manifold long enough to become thoroughly heated, and was then ignited by the exhaust gas which had not mixed with cooling air. The use of the air-inducting exhaust manifold must reduce the fire hazard by virtue of its lower operating temperature, but it is not a completely satisfactory solution of the problem.

Schey, Oscar W; Young, Alfred W

1931-01-01

458

THE INFLUENCE OF PARTICULATE AIR POLLUTANTS ON ALLERGIC SENSITIZATION IN ANIMAL MODELS  

EPA Science Inventory

Air pollution has long been associated with detrimental health risks in susceptible populations including asthmatics. Experimental evidence in rodents indicates that inhaled or instilled air pollutants such as diesel exhaust particles (DEPs), residual oil fly ash or its constitu...

459

Modifications in Ginkgo biloba L. in response to environmental pollution  

SciTech Connect

Ginkgo biloba L. (maidenhair tree) was studied in polluted and relatively clean habitats of West Tennessee. In spite of its known resistance to smog and automobile exhaust fumes, it exhibited a decrease in leaf length, leaf width, and petiole length in polluted habitats. Furthermore, there was a definite trend towards lower stomatal density along the pollution gradient in selected habitats.

Sharma, G.K. (Univ. to Tennessee, Martin (USA))

1989-01-01

460

AEROJET: nonintrusive measurements of aircraft engine exhaust emissions  

NASA Astrophysics Data System (ADS)

The environment impact of air traffic and economical aspects require aircraft engines to be developed which have reduced trace gas emissions and, at the same time, increased efficiency. Each new engine must be shown to meet the environmental requirements laid down by regulatory bodies, and exhaust gas measurements must be performed for the certification. The goal of the EC project AEROJET is to demonstrate the equivalence of remote measurement techniques to conventional extractive methods for both gaseous and particulate measurements. The different remote measurement techniques will be compared and calibrated. A demonstrator measurement system for exhaust gases, temperature and particulates including data-analysis software will be regarded as result of this project.

Schaefer, Klaus; Heland, Joerg; Burrows, Roger; Black, John V.; Bernard, Marc; Bishop, Gary; Tank, Volker; Lindermeir, Erwin; Lister, Dave H.; Falk, Robert S.; Wiesen, Peter; Hilton, Moira

1997-05-01

461

Power Exhaust in Fusion Plasmas  

NASA Astrophysics Data System (ADS)

Preface; 1. Introduction; 2. Magnetized plasma physics; 3. Magnetized plasma equilibrium; 4. Magnetized plasma stability; 5. Collisional transport in magnetized plasmas; 6. Turbulent transport in magnetized plasmas; 7. Tokamak plasma boundary and power exhaust; 8. Outlook: power exhaust in fusion reactors; Appendix A. Maxwellian distribution; Appendix B. Curvilinear co-ordinates; References; Index.

Fundamenski, Wojciech

2014-07-01

462

Treatment of power utilities exhaust  

SciTech Connect

Provided is a process for treating nitrogen oxide-containing exhaust produced by a stationary combustion source by the catalytic reduction of nitrogen oxide in the presence of a reductant comprising hydrogen, followed by ammonia selective catalytic reduction to further reduce the nitrogen oxide level in the exhaust.

Koermer, Gerald (Basking Ridge, NJ)

2012-05-15

463

Automotive Fuel and Exhaust Systems.  

ERIC Educational Resources Information Center

Materials are provided for a 14-hour course designed to introduce the automotive mechanic to the basic operations of automotive fuel and exhaust systems incorporated on military vehicles. The four study units cover characteristics of fuels, gasoline fuel system, diesel fuel systems, and exhaust system. Each study unit begins with a general…

Irby, James F.; And Others

464

RESPONSES OF CULTURED HUMAN AIRWAY EPITHELIAL CELLS TREATED WITH DIESEL EXHAUST EXTRACTS WILL VARY WITH THE ENGINE  

EPA Science Inventory

Epidemiologic evidence suggests that increased morbidity and mortality are associated with the concentrations of ambient air particulate matter (PM). Many sources contribute to the particulate fraction of ambient pollution, including diesel exhaust particulates (DEP). Diesel ex...

465

Exhaust Heat Recovery  

Microsoft Academic Search

\\u000a Although public awareness of the finiteness of fossil fuel reserves has receded into the background somewhat since it was\\u000a raised in the 1970s, the impact of pollutant and CO2 input into the earth’s atmosphere is again making the need for a longer range environmentally compatible energy policy with\\u000a concrete goals evident.

Franz Hirschbichler

466

Effects of prenatal exposure to diesel exhaust particles on postnatal development, behavior, genotoxicity and inflammation in mice  

Microsoft Academic Search

BACKGROUND: Results from epidemiological studies indicate that particulate air pollution constitutes a hazard for human health. Recent studies suggest that diesel exhaust possesses endocrine activity and therefore may affect reproductive outcome. This study in mice aimed to investigate whether exposure to diesel exhaust particles (DEP; NIST 2975) would affect gestation, postnatal development, activity, learning and memory, and biomarkers of transplacental

Karin S Hougaard; Keld A Jensen; Pernille Nordly; Camilla Taxvig; Ulla Vogel; Anne T Saber; Håkan Wallin

2008-01-01

467

Preliminary assessment of a potassium-steam-gas vapor cycle for better fuel economy and reduced thermal pollution  

Microsoft Academic Search

The facts of fuel supply limitations, environmental quality demands, and spiraling electric generating costs strongly favor development of electric power plants that simultaneously run at higher efficiency, i.e., higher temperature, use to advantage clean fuels, and have as low a capital cost as possible. Both fuel supply and thermal pollution considerations that are becoming progressively more important strongly favor the

Fraas

1971-01-01

468

Study Pinpoints Sources of Polluting Vehicle Emissions (Fact Sheet)  

SciTech Connect

Unburned lubricant produces 60%-90% of organic carbon emissions. While diesel fuel is often viewed as the most polluting of conventional petroleum-based fuels, emissions from gasoline engines can more significantly degrade air quality. Gasoline exhaust is at least as toxic on a per-unit-mass basis as diesel exhaust, and contributes up to 10 times more particulate matter (PM) to the emission inventory. Because emissions from both fuels can gravely impact health and the environment, researchers at the National Renewable Energy Laboratory (NREL) launched a study to understand how these pollutants relate to fuels, lubricants, and engine operating conditions. NREL's Collaborative Lubricating Oil Study on Emissions (CLOSE) project tested a variety of vehicles over different drive cycles at moderate (72 F) and cold (20 F) temperatures. Testing included: (1) Normal and high-emitting light-, medium-, and heavy-duty vehicles; (2) Gasoline, diesel, and compressed natural gas (CNG)-powered vehicles; (3) New and aged lubricants representative of those currently on the market; and (4) Gasoline containing no ethanol, E10, Texas-mandated low-emission diesel fuel, biodiesel, and CNG. The study confirmed that normally functioning emission control systems for gasoline light-duty vehicles are very effective at controlling organic carbon (OC) emissions. Diesel vehicles without aftertreatment emission control systems exhibited OC emissions approximately one order of magnitude higher than gasoline vehicles. High-emitter gasoline vehicles produced OC emissions similar to diesel vehicles without exhaust aftertreatment emission control. Exhaust catalysts combusted or converted more than 75% of lubricating oil components in the exhaust gases. Unburned crankcase lubricant made up 60%-90% of OC emissions. This OC represented 20%-50% of emitted PM in all but two of the vehicles. Three-way catalysts proved effective at reducing most of the OC. With high PM emitters or vehicles with deteriorated aftertreatment, high-molecular-weight fuel components and unburned lubricant were emitted at higher rates than in vehicles in good repair, with functioning emissions systems. Light-duty gasoline, medium-duty diesel, and heavy-duty natural gas vehicles produced more particles with fresh oil than with aged oil. The opposite trend was observed in light- and medium-duty high PM emitters. This effect was not readily apparent with heavy-duty diesel vehicles, perhaps because the lubricant represented a much smaller fraction of the total PM in those trucks.

Not Available

2012-03-01

469

Evaluation test on a landfill gas-fired turbine at the Los Angeles County Sanitation District's Puente Hill Landfill Electric Generation Station. Air pollution test report  

SciTech Connect

A cooperative test program was conducted from February 25 through February 27, 1986 by Air Resources Board (ARB) and South Coast Air Quality Management District (SCAQMD) staff to evaluate the gaseous constituents from untreated landfill gas used to fuel a turbine and the emissions from that turbine located at the Los Angeles County Sanitation District's Puente Hills Electric Generating Station. The turbine was fueled with gases generated by the anaerobic decomposition of buried refuse at the Los Angeles County Sanitation District's Puente Hills Landfill. Emissions of criteria pollutant as determined from ARB test data are reported. Mass flow rates and destruction and removal efficiencies (DRE) of non-criteria pollutant compounds determined at the stack from SCQAMD bag-sample test data and mass-flow rates and DRE's for chlorinated and aromatic compounds determined from data from ARB resin samples are presented. Destruction and removal efficiencies based on mass-flow rates for chlorinated compounds ranged from 17 to 99+ percent and for aromatic compounds ranged from negative to 99+ percent. The possible formation of the compounds - chlorinated dioxins, furans, and polychlorinated biphenyls - was considered and samples were taken for analyses for these compounds. Dioxins, furans, and polychlorinated biphenyls were not detected in the inlet nor the outlet gas stream samples.

Not Available

1986-07-01

470

Exhaust gas purifier for internal combustion engine  

Microsoft Academic Search

Disclosed is a catalytic converter of cassette type having a monolithic honeycomb structure of catalyst-coated ceramic body which is resiliently supported within an outer cylindrical metal shell. The shell includes first and second circumferential portions of an equal diameter which are at opposite axial ends thereof, and a third circumferential portion located therebetween and which has a greater outer diameter

Aoyama

1979-01-01

471

A down-exhaust cyclone separator  

SciTech Connect

In this paper the authors report on the development of a down-exhaust cyclone separator suitable for use as a primary device for gas-particle separation in circulating fluidized-bed (CFB) boilers. It consists of a cylindrical shell which is joined by an inclined cone, a guide body, and a downward exhaust pipe. The principle of solids separation is similar to that in reverse flow cyclones, except that in this separator the gas leaves the separator axially at the bottom. It has been shown that this separator is capable of achieving a separation efficiency of around 99% in handling high solids loadings such as those in CFB boilers, at a pressure drop of around 400 Pa. A model based on the mechanism of radial solids mixing is proposed, which assumes that the slip between gas and particles in the tangential direction is negligible and that the particles are well-dispersed. This model enables prediction of grade separation efficiency, total separation efficiency, and cut diameter. It may be used in conjunction with a pressure drop model to optimize the design and operating parameters.

Chen, H.P.; Lin, Z.J.; Liu, D.C. [Huazhong Univ. of Science and Technology, Wuhan, Hubei (China). National Lab. of Coal Combustion] [Huazhong Univ. of Science and Technology, Wuhan, Hubei (China). National Lab. of Coal Combustion; Wang, X.S.; Rhodes, M.J. [Monash Univ., Clayton, Victoria (Australia). Dept. of Chemical Engineering] [Monash Univ., Clayton, Victoria (Australia). Dept. of Chemical Engineering

1999-04-01

472

Dioxin-receptor ligands in urban air and vehicle exhaust.  

PubMed Central

The ability of extracts of urban air and vehicle exhaust particulates to bind to the dioxin receptor has been determined. It was shown that such extracts do contain significant amounts of dioxin-receptor binding activity. The level of dioxin-receptor binding found in ambient air reflects its pollution level as determined by mutagenic activity. Furthermore, it was shown that the extracts of both urban air and vehicle exhaust particulates could provoke the induction of cytochrome P450IA1 in cultured rat hepatoma cells. Chemical fractionation of the extracts revealed that the majority of the dioxin-receptor binding activity from urban air and gasoline vehicle samples fractionated with the polycyclic aromatic compounds. However, unknown polycyclic aromatic compounds were responsible for the majority of the binding activity measured. In the case of diesel vehicle exhausts, the majority of the dioxin-receptor binding activity was found to be associated with nitro-polycyclic aromatic compounds. Studies with a variety of diesel fuels showed that the amount of dioxin-receptor ligands present in exhaust emissions are fuel-dependent and that substantial amounts of dioxin-receptor ligands are present in the semivolatile phase of exhaust emissions. PMID:7529698

Mason, G G

1994-01-01

473

On-Line Analysis of Organic Compounds in Diesel Exhaust Using Proton-Transfer-Reaction Mass Spectrometry  

SciTech Connect

In this study, diesel exhaust (DE) was measured in real time using a proton-transfer-reaction mass spectrometer (PTR-MS) to determine the effect of an after-treatment catalyst on gas phase volatile organic compounds (VOCs). DE after-treatment catalysts are being designed to reduce the pollutants in exhaust, which contains both particulate matter and gas phase constituents. The PTR-MS can make in-situ real time measurements of hydrocarbons in the air, from concentrations in the parts per million by volume (ppmV) down to the low part per trillion by volume (pptV) range. Spectrum scans were performed at varied engine loads from mass range m/z (mass to charge ratio) = 20 to 200. This showed the relative abundance of gas phase VOCs produced as the engine ran between idle mode and 80% of its maximum load. The mass spectrum was complex and appeared to be composed of aromatic species ionized by PTR (M+1) through the anticipated proton transfer reactions as well as unexpected alkane fragments, evidenced by a strong 14n+1 ion pattern showing intense peaks at m/z = 43, 57, and 71. A number of protonated M+1 masses could be identified. These compounds displayed M+2 peaks consisten