Science.gov

Sample records for ambient air engine

  1. Ambient air cooling arrangement having a pre-swirler for gas turbine engine blade cooling

    DOEpatents

    Lee, Ching-Pang; Tham, Kok-Mun; Schroeder, Eric; Meeroff, Jamie; Miller, Jr., Samuel R; Marra, John J

    2015-01-06

    A gas turbine engine including: an ambient-air cooling circuit (10) having a cooling channel (26) disposed in a turbine blade (22) and in fluid communication with a source (12) of ambient air: and an pre-swirler (18), the pre-swirler having: an inner shroud (38); an outer shroud (56); and a plurality of guide vanes (42), each spanning from the inner shroud to the outer shroud. Circumferentially adjacent guide vanes (46, 48) define respective nozzles (44) there between. Forces created by a rotation of the turbine blade motivate ambient air through the cooling circuit. The pre-swirler is configured to impart swirl to ambient air drawn through the nozzles and to direct the swirled ambient air toward a base of the turbine blade. The end walls (50, 54) of the pre-swirler may be contoured.

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

    NASA Astrophysics Data System (ADS)

    Masiol, Mauro; Harrison, Roy M.

    2014-10-01

    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.

  3. Chemical analysis and biological testing of a polar fraction of ambient air, diesel engine, and gasoline engine particulate extracts.

    PubMed Central

    Strandell, M; Zakrisson, S; Alsberg, T; Westerholm, R; Winquist, L; Rannug, U

    1994-01-01

    Extracts of gasoline and diesel vehicle exhaust and ambient air particles were fractionated into five fractions according to polarity on a silica gel column. Two medium polar fractions showing high genotoxic activity in the Ames test were further subfractionated, using normal-phase high-performance liquid chromatography. Chemical analyses were performed by means of gas chromatography combined with mass spectrometry and flame ionization and detection. The crude extracts, fractions, and subfractions were assayed with the Ames test, with and without S9, and the most abundant compounds in the subfractions are reported. PMID:7529708

  4. Ambient Air Definition

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  5. Ambient air quality in Slovak Republic

    SciTech Connect

    Violova, A.; Cremonini, M.G.; Lombardo, P.; Stenhouse, I.A.; Kocan, A.

    1998-07-01

    The National Government of the Slovak Republic is committed to develop an integrated strategy that will take into account global, regional and local aspects of the national emissions of pollutants. Priority is given to ambient air quality, with particular reference to human health protection. Only limited information on ambient air concentrations of hazardous air pollutants (HAP) was available in Slovakia. A comprehensive ambient air quality project has been recently funded by the European Union Phare Programme. The project was performed under the technical supervision of the Slovak Ministry of the Environment and aimed at monitoring the ambient air quality with respect to Volatile Organic Compounds (VOCs), persistent Organic Pollutants (POPs) and heavy metals (HMs), identifying and evaluating main potential pollution sources, and defining general strategies to reduce impacts.

  6. Ambient air contamination: Characterization and detection techniques

    NASA Technical Reports Server (NTRS)

    Nulton, C. P.; Silvus, H. S.

    1985-01-01

    Techniques to characterize and detect sources of ambient air contamination are described. Chemical techniques to identify indoor contaminants are outlined, they include gas chromatography, or colorimetric detection. Organics generated from indoor materials at ambient conditions and upon combustion are characterized. Piezoelectric quartz crystals are used as precision frequency determining elements in electronic oscillators.

  7. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  8. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  9. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  10. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  11. 40 CFR 51.190 - Ambient air quality monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Ambient air quality monitoring... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Ambient Air Quality Surveillance § 51.190 Ambient air quality monitoring requirements. The requirements for monitoring ambient...

  12. 40 CFR 51.190 - Ambient air quality monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Ambient air quality monitoring... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Ambient Air Quality Surveillance § 51.190 Ambient air quality monitoring requirements. The requirements for monitoring ambient...

  13. 40 CFR 51.190 - Ambient air quality monitoring requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Ambient air quality monitoring... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Ambient Air Quality Surveillance § 51.190 Ambient air quality monitoring requirements. The requirements for monitoring ambient...

  14. 40 CFR 51.190 - Ambient air quality monitoring requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Ambient air quality monitoring... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Ambient Air Quality Surveillance § 51.190 Ambient air quality monitoring requirements. The requirements for monitoring ambient...

  15. 40 CFR 51.190 - Ambient air quality monitoring requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Ambient air quality monitoring... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Ambient Air Quality Surveillance § 51.190 Ambient air quality monitoring requirements. The requirements for monitoring ambient...

  16. Deployable Engine Air Brake

    NASA Technical Reports Server (NTRS)

    2014-01-01

    On approach, next-generation aircraft are likely to have airframe noise levels that are comparable to or in excess of engine noise. ATA Engineering, Inc. (ATA) is developing a novel quiet engine air brake (EAB), a device that generates "equivalent drag" within the engine through stream thrust reduction by creating a swirling outflow in the turbofan exhaust nozzle. Two Phase II projects were conducted to mature this technology: (1) a concept development program (CDP) and (2) a system development program (SDP).

  17. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  18. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  19. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  20. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  1. Exercise and outdoor ambient air pollution

    PubMed Central

    Carlisle, A; Sharp, N

    2001-01-01

    Objectives—To establish by literature survey: (a) levels at which air pollutants are considered damaging to human health and to exercisers in particular; (b) the current ambient levels experienced in the United Kingdom; (c) whether athletes are especially at risk. Methods—Six major urban air pollutants were examined: carbon monoxide (CO); nitrogen oxides (NOX); ozone (O3); particulate matter (PM10); sulphur dioxide (SO2); volatile organic compounds (VOCs). Results—CO is detrimental to athletic performance. NO2 is of concern to human health, but outdoor levels are low. O3 poses a potentially serious risk to exercising athletes. Decrements in lung function result from exposure, and there is evidence that athletic performance may be affected. Detrimental effects may occur at low ambient levels, but there is no scientific consensus on this matter. PM10 is causing concern in the scientific community. Blood lead accumulation during exercise indicates that personal exposure to toxic compounds associated with PM10 may be magnified. Generally, outdoor ambient levels of SO2 are too low to cause a problem to the athlete, except the asthmatic athlete. The few studies on exposure of exercisers to VOCs are reviewed. Conclusions—Athletes and exercisers should avoid exercising by the road side even though levels of the more noxious air pollutants have been controlled in the United Kingdom. O3 is particularly damaging to athletes; it reaches its highest concentrations on hot bright days in rural areas. Key Words: exercise; air pollution PMID:11477012

  2. Antimicrobial Applications of Ambient--Air Plasmas

    NASA Astrophysics Data System (ADS)

    Pavlovich, Matthew John

    The emerging field of plasma biotechology studies the applications of the plasma phase of matter to biological systems. "Ambient-condition" plasmas created at or near room temperature and atmospheric pressure are especially promising for biomedical applications because of their convenience, safety to patients, and compatibility with existing medical technology. Plasmas can be created from many different gases; plasma made from air contains a number of reactive oxygen and nitrogen species, or RONS, involved in various biological processes, including immune activity, signaling, and gene expression. Therefore, ambient-condition air plasma is of particular interest for biological applications. To understand and predict the effects of treating biological systems with ambient-air plasma, it is necessary to characterize and measure the chemical species that these plasmas produce. Understanding both gaseous chemistry and the chemistry in plasma-treated aqueous solution is important because many biological systems exist in aqueous media. Existing literature about ambient-air plasma hypothesizes the critical role of reactive oxygen and nitrogen species; a major aim of this dissertation is to better quantify RONS by produced ambient-air plasma and understand how RONS chemistry changes in response to different plasma processing conditions. Measurements imply that both gaseous and aqueous chemistry are highly sensitive to operating conditions. In particular, chemical species in air treated by plasma exist in either a low-power ozone-dominated mode or a high-power nitrogen oxide-dominated mode, with an unstable transition region at intermediate discharge power and treatment time. Ozone (O3) and nitrogen oxides (NO and NO2, or NOx) are mutually exclusive in this system and that the transition region corresponds to the transition from ozone- to nitrogen oxides-mode. Aqueous chemistry agrees well with to air plasma chemistry, and a similar transition in liquid-phase composition

  3. Ambient air pollution and population health: overview.

    PubMed

    Krewski, Daniel; Rainham, Daniel

    2007-02-01

    In November 2003 approximately 200 researchers, stakeholders, and policymakers from more than 40 countries gathered to discuss the science and policy implications of air pollution and human health as part of the AIRNET/NERAM Strategies for Clean Air and Health initiative. The purpose of this paper is to review the more than 35 research posters presented at the conference, including exposure, toxicological, and epidemiological studies of air pollution. Collectively, these papers support previous evidence that both short- and long-term exposures to particulate air pollution have adverse population health impacts, including effects on children. Cellular studies also suggest that air pollution can cause mutagenic and oxidative effects, raising concerns about carcinogenicity and cellular regeneration. Studies of biomarkers, such as Clara-cell proteins and lymphocyte damage assessment, provide further evidence of air pollution effects at the cellular level. Other studies have focused on improvements to measurement and sources of air pollution. These studies suggest that particle mass rather than particle composition may be a more useful indicator of potential human health risk. It is well known that emissions from transportation sources are a major contributor to ambient air pollution in large urban centres. Epidemiologic researchers are able to reduce bias due to misclassification and improve exposure assessment models by allocating air pollution exposure according to distance from traffic sources or land-use patterns. The close association between traffic patterns and air pollution concentrations provides a potential basis for the development of transport policies and regulations with population health improvements as a primary objective. The results of the research presented here present opportunities and challenges for the development of policies for improvements to air quality and human health. However, there remains the challenge of how best to achieve these

  4. Assessment of SRS ambient air monitoring network

    SciTech Connect

    Abbott, K.; Jannik, T.

    2016-08-03

    Three methodologies have been used to assess the effectiveness of the existing ambient air monitoring system in place at the Savannah River Site in Aiken, SC. Effectiveness was measured using two metrics that have been utilized in previous quantification of air-monitoring network performance; frequency of detection (a measurement of how frequently a minimum number of samplers within the network detect an event), and network intensity (a measurement of how consistent each sampler within the network is at detecting events). In addition to determining the effectiveness of the current system, the objective of performing this assessment was to determine what, if any, changes could make the system more effective. Methodologies included 1) the Waite method of determining sampler distribution, 2) the CAP88- PC annual dose model, and 3) a puff/plume transport model used to predict air concentrations at sampler locations. Data collected from air samplers at SRS in 2015 compared with predicted data resulting from the methodologies determined that the frequency of detection for the current system is 79.2% with sampler efficiencies ranging from 5% to 45%, and a mean network intensity of 21.5%. One of the air monitoring stations had an efficiency of less than 10%, and detected releases during just one sampling period of the entire year, adding little to the overall network intensity. By moving or removing this sampler, the mean network intensity increased to about 23%. Further work in increasing the network intensity and simulating accident scenarios to further test the ambient air system at SRS is planned

  5. Ambient air pollution: a cause of COPD?

    PubMed

    Schikowski, Tamara; Mills, Inga C; Anderson, H Ross; Cohen, Aaron; Hansell, Anna; Kauffmann, Francine; Krämer, Ursula; Marcon, Alessandro; Perez, Laura; Sunyer, Jordi; Probst-Hensch, Nicole; Künzli, Nino

    2014-01-01

    The role of ambient air pollution in the development of chronic obstructive pulmonary disease (COPD) is considered to be uncertain. We review the evidence in the light of recent studies. Eight morbidity and six mortality studies were identified. These were heterogeneous in design, characterisation of exposure to air pollution and methods of outcome definition. Six morbidity studies with objectively defined COPD (forced expiratory volume in 1 s/forced vital capacity ratio) were cross-sectional analyses. One longitudinal study defined incidence of COPD as the first hospitalisation due to COPD. However, neither mortality nor hospitalisation studies can unambiguously distinguish acute from long-term effects on the development of the underlying pathophysiological changes. Most studies were based on within-community exposure contrasts, which mainly assess traffic-related air pollution. Overall, evidence of chronic effects of air pollution on the prevalence and incidence of COPD among adults was suggestive but not conclusive, despite plausible biological mechanisms and good evidence that air pollution affects lung development in childhood and triggers exacerbations in COPD patients. To fully integrate this evidence in the assessment, the life-time course of COPD should be better defined. Larger studies with longer follow-up periods, specific definitions of COPD phenotypes, and more refined and source-specific exposure assessments are needed.

  6. Ambient air monitoring to support HLW repository site characterization

    SciTech Connect

    Fransioli, P.M.; Dixon, W.R.

    1993-12-31

    Site characterization at the Yucca Mountain site includes an ambient air quality and meteorological monitoring program to provide information for environmental and site characterization issues. The program is designed to provide data for four basic purposes: Atmospheric dispersion calculations to estimate impacts of possible airborne releases of radiological material; Engineering design and extreme weather event characterization; Local climate studies for environmental impact analyses and climate characterization; and, Air quality permits required for site characterization work. The program is compiling a database that will provide the basis for analyses and reporting related to the purposes of the program. Except for reporting particulate matter and limited meteorological data to the State of Nevada for an air quality permit condition, the data have yet to be formally analyzed and reported.

  7. Liquid air cycle engines

    NASA Technical Reports Server (NTRS)

    Rosevear, Jerry

    1992-01-01

    Given here is a definition of Liquid Air Cycle Engines (LACE) and existing relevant technologies. Heat exchanger design and fabrication techniques, the handling of liquid hydrogen to achieve the greatest heat sink capabilities, and air decontamination to prevent heat exchanger fouling are discussed. It was concluded that technology needs to be extended in the areas of design and fabrication of heat exchangers to improve reliability along with weight and volume reductions. Catalysts need to be improved so that conversion can be achieved with lower quantities and lower volumes. Packaging studies need to be investigated both analytically and experimentally. Recycling with slush hydrogen needs further evaluation with experimental testing.

  8. 40 CFR 52.14 - State ambient air quality standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false State ambient air quality standards. 52.14 Section 52.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than...

  9. 40 CFR 52.14 - State ambient air quality standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false State ambient air quality standards. 52.14 Section 52.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than...

  10. 40 CFR 52.14 - State ambient air quality standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false State ambient air quality standards. 52.14 Section 52.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than...

  11. 40 CFR 52.14 - State ambient air quality standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false State ambient air quality standards. 52.14 Section 52.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than...

  12. 40 CFR 52.14 - State ambient air quality standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false State ambient air quality standards. 52.14 Section 52.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than...

  13. Wash-out of ambient air contaminations for breath measurements.

    PubMed

    Maurer, F; Wolf, A; Fink, T; Rittershofer, B; Heim, N; Volk, T; Baumbach, J I; Kreuer, S

    2014-06-01

    In breath analysis, ambient air contaminations are ubiquitous and difficult to eliminate. This study was designed to investigate the reduction of ambient air background by a lung wash-out with synthetic air. The reduction of the initial ambient air volatile organic compound (VOC) intensity was investigated in the breath of 20 volunteers inhaling synthetic air via a sealed full face mask in comparison to inhaling ambient air. Over a period of 30 minutes, breath analysis was conducted using ion mobility spectrometry coupled to a multi-capillary column. A total of 68 VOCs were identified for inhaling ambient air or inhaling synthetic air. By treatment with synthetic air, 39 VOCs decreased in intensity, whereas 29 increased in comparison to inhaling ambient air. In total, seven VOCs were significantly reduced (P-value < 0.05). A complete wash-out of VOCs in this setting was not observed, whereby a statistically significant reduction up to 65% as for terpinolene was achieved. Our setting successfully demonstrated a reduction of ambient air contaminations from the airways by a lung wash-out with synthetic air.

  14. WORKSHOP ON SOURCE EMISSION AND AMBIENT AIR MONITORING OF MERCURY

    EPA Science Inventory

    AN EPA/ORD Workshop on Source Emission and Ambient Air Monitoring of Mercury was held on 9/13-14/99, Bloomington, Minnesota. The purpose of the workshop was to discuss the state-of-the-science in source and ambient air mercury monitoring as well as mercury monitoring research and...

  15. 77 FR 12482 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... Clean Air Act (CAA). This submittal incorporates the National Ambient Air Quality Standards (NAAQS)...

  16. 77 FR 12524 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule...) under the Clean Air Act (CAA). This submittal incorporates the National Ambient Air Quality...

  17. 78 FR 34177 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements... Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements AGENCY: Environmental... 2008 ozone national ambient air quality standards (NAAQS) (the ``2008 ozone NAAQS'') that...

  18. Engineering system for simultaneous inhalation exposures of rodents to fine and ultrafine concentrated ambient particulate matter from a common air source

    EPA Science Inventory

    Exposure to elevated levels of ambient particulate matter (PM) smaller than 2.5 11m (PM2.5) has been associated with adverse health effects in both humans and animals. Specific properties of either fine (0.1-2.5 11m), or ultrafine « 0.1 11m) PM responsible for exposure related he...

  19. A Study on the Air flow outside Ambient Vaporizer Fin

    NASA Astrophysics Data System (ADS)

    Oh, G.; Lee, T.; Jeong, H.; Chung, H.

    2015-09-01

    In this study, we interpreted Fog's Fluid that appear in the Ambient Vaporizer and predict the point of change Air to Fog. We interpreted using Analysis working fluid was applied to LNG and Air. We predict air flow when there is chill of LNG in the air Temperature and that makes fog. Also, we interpreted based on Summer and Winter criteria in the air temperature respectively. Finally, we can check the speed of the fog when fog excreted.

  20. 40 CFR 52.995 - Enhanced ambient air quality monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Enhanced ambient air quality monitoring. 52.995 Section 52.995 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... air quality monitoring. (a) The Governor of the State of Louisiana submitted the...

  1. 40 CFR 52.995 - Enhanced ambient air quality monitoring.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Enhanced ambient air quality monitoring. 52.995 Section 52.995 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... air quality monitoring. (a) The Governor of the State of Louisiana submitted the...

  2. 40 CFR Appendix C to Part 58 - Ambient Air Quality Monitoring Methodology

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Ambient Air Quality Monitoring... PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App. C Appendix C to Part 58—Ambient Air Quality Monitoring Methodology 1.0 Purpose 2.0 SLAMS Ambient Air Monitoring Stations 3.0 NCore Ambient...

  3. 40 CFR Appendix C to Part 58 - Ambient Air Quality Monitoring Methodology

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Ambient Air Quality Monitoring... PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App. C Appendix C to Part 58—Ambient Air Quality Monitoring Methodology 1.0 Purpose 2.0 SLAMS Ambient Air Monitoring Stations 3.0 NCore Ambient...

  4. [Ambient and enclosed space air sampling for determination of contaminants].

    PubMed

    Dorogova, V B

    2010-01-01

    The paper touches upon the issues how to correctly and maximally take single and average daily samples of ambient, residential and public building, and enclosed space air for further tests for the content of hazardous substances. The paper is debated.

  5. Draft Final Ambient Air Monitoring Plan July 2015

    EPA Pesticide Factsheets

    This work plan describes the ambient air sampling program for the New Bedford Harbor Superfund Site and presents the locations, sampling strategies, and exposure limits for monitoring remedial activities in the Harbor.

  6. 77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... 21, 2012 Part III Environmental Protection Agency 40 CFR Parts 50, 51 and 81 Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards; Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area Classifications Approach, Attainment Deadlines...

  7. 78 FR 63878 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air Quality Standards for Fine Particulate Matter AGENCY: Environmental Protection Agency (EPA... Commonwealth of Virginia State Implementation Plan (SIP). The revisions add ambient air quality standards...

  8. 75 FR 65594 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY... consolidation of Ohio's Ambient Air Quality Standards (AAQS) into Ohio's State Implementation Plan (SIP)...

  9. 75 FR 65572 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... of Ohio's Ambient Air Quality Standards (AAQS) into Ohio's State Implementation Plan (SIP) under...

  10. 78 FR 63933 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air Quality Standards for Fine Particulate Matter AGENCY: Environmental Protection Agency (EPA... submitted by the Commonwealth of Virginia adding ambient air quality standards and associated...

  11. Plain-jet airblast atomization of alternative liquid petroleum fuels under high ambient air pressure conditions

    NASA Astrophysics Data System (ADS)

    Jasuja, A. K.

    1982-04-01

    The effects that air and fuel properties have upon the spray mean drop size characteristics of a plain-jet airblast atomizer of the type employed in the gas turbine engine are investigated. The tests used kerosene, gas oil and a high-viscosity blend of gas oil in residual fuel oil, and covered a wide range of ambient air pressures. Laser light-scattering technique was employed for drop size measurements. It is concluded that the atomizer's measured mean drop size characteristics are only slightly different from those of the pre-filming type, especially when operating on low-viscosity kerosene under higher ambient air pressure. The beneficial effect of increased levels of ambient air pressure on mean drop size is shown to be much reduced in the case of high-viscosity fuels, thus making the attainment of good atomization performance on such fuels difficult. An expression is derived for correlating the obtained mean drop size data.

  12. 76 FR 72097 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... IQ Intelligence Quotient NAAQS National Ambient Air Quality Standards NTTAA National Technology... systems (including their brains) arising from Pb exposure may include intelligence quotient (IQ)...

  13. METHODOLOGY OF AMBIENT AIR MONITORING FOR POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    In the last decade, several studies of polycyclic aromatic hydrocarbons (PAH) in ambient air in the U.S. specifically investigated (1) the sampling efficiency of two sorbents for PAH in air: XAD-2 and polyurethane foam (PUP); (2) the storage stability of PAH on quartz fiber fil...

  14. Development of Quality Control Parameters and Electronic Data Recording for an Ambient Air Particle Inhalation Exposure System

    EPA Science Inventory

    Ambient air particle concentrating systems were installed by the US EPA in RTP, NC. These systems, designed by Harvard School of Public Health’s Department of Environmental Sciences and Engineering (Boston, MA), concentrated ambient fine and ultra-fine mode particulate matter (P...

  15. Variable oxygen/nitrogen enriched intake air system for internal combustion engine applications

    DOEpatents

    Poola, Ramesh B.; Sekar, Ramanujam R.; Cole, Roger L.

    1997-01-01

    An air supply control system for selectively supplying ambient air, oxygen enriched air and nitrogen enriched air to an intake of an internal combustion engine includes an air mixing chamber that is in fluid communication with the air intake. At least a portion of the ambient air flowing to the mixing chamber is selectively diverted through a secondary path that includes a selectively permeable air separating membrane device due a differential pressure established across the air separating membrane. The permeable membrane device separates a portion of the nitrogen in the ambient air so that oxygen enriched air (permeate) and nitrogen enriched air (retentate) are produced. The oxygen enriched air and the nitrogen enriched air can be selectively supplied to the mixing chamber or expelled to atmosphere. Alternatively, a portion of the nitrogen enriched air can be supplied through another control valve to a monatomic-nitrogen plasma generator device so that atomic nitrogen produced from the nitrogen enriched air can be then injected into the exhaust of the engine. The oxygen enriched air or the nitrogen enriched air becomes mixed with the ambient air in the mixing chamber and then the mixed air is supplied to the intake of the engine. As a result, the air being supplied to the intake of the engine can be regulated with respect to the concentration of oxygen and/or nitrogen.

  16. Passive radiative cooling below ambient air temperature under direct sunlight.

    PubMed

    Raman, Aaswath P; Anoma, Marc Abou; Zhu, Linxiao; Rephaeli, Eden; Fan, Shanhui

    2014-11-27

    Cooling is a significant end-use of energy globally and a major driver of peak electricity demand. Air conditioning, for example, accounts for nearly fifteen per cent of the primary energy used by buildings in the United States. A passive cooling strategy that cools without any electricity input could therefore have a significant impact on global energy consumption. To achieve cooling one needs to be able to reach and maintain a temperature below that of the ambient air. At night, passive cooling below ambient air temperature has been demonstrated using a technique known as radiative cooling, in which a device exposed to the sky is used to radiate heat to outer space through a transparency window in the atmosphere between 8 and 13 micrometres. Peak cooling demand, however, occurs during the daytime. Daytime radiative cooling to a temperature below ambient of a surface under direct sunlight has not been achieved because sky access during the day results in heating of the radiative cooler by the Sun. Here, we experimentally demonstrate radiative cooling to nearly 5 degrees Celsius below the ambient air temperature under direct sunlight. Using a thermal photonic approach, we introduce an integrated photonic solar reflector and thermal emitter consisting of seven layers of HfO2 and SiO2 that reflects 97 per cent of incident sunlight while emitting strongly and selectively in the atmospheric transparency window. When exposed to direct sunlight exceeding 850 watts per square metre on a rooftop, the photonic radiative cooler cools to 4.9 degrees Celsius below ambient air temperature, and has a cooling power of 40.1 watts per square metre at ambient air temperature. These results demonstrate that a tailored, photonic approach can fundamentally enable new technological possibilities for energy efficiency. Further, the cold darkness of the Universe can be used as a renewable thermodynamic resource, even during the hottest hours of the day.

  17. Air-Breathing Rocket Engines

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  18. METHODOLOGY FOR SITING AMBIENT AIR MONITORS AT THE NEIGHBORHOOD SCALE

    EPA Science Inventory

    In siting a monitor to measure compliance with U.S. National Ambient Air Quality Standards for particulate matter (PM), there is a need to characterize variations in PM concentration within a neighborhood-scale region in order to achieve monitor siting objectives.

    We p...

  19. ORGANOCHLORINE PESTICIDES IN THE AMBIENT AIR OF MEXICO

    EPA Science Inventory

    Recent and past use of organochlorine pesticides (OCPs) in Mexico has resulted in concentrations in ambient air that are 1-2 orders of magnitude above levels in the Great Lakes region. Atmospheric transport from Mexico and Central America may be contributing significant amounts ...

  20. Performance testing and analysis of vertical ambient air vaporizers

    NASA Astrophysics Data System (ADS)

    Pandey, A. S.; Singh, V. N.; Shah, M. I.; Acharya, D. V.

    2017-02-01

    Ambient air vaporizers are used to regasify cryogenic liquids at extremely low temperature (below -153°C). Frost formation occurs on it due to large temperature difference between ambient air and cryogenic fluid. Frosting induces additional load on equipment and reduces its heat transfer effectiveness. Hence, mechanical and thermal design of vaporizers account for frosting. An experimental set-up has been designed and effects of flow rate and ground clearance on the performance of ambient air vaporizers are evaluated. The flow rate is increased from the rated capacity of 500 Nm3/h to 640 Nm3/h and ground clearance is reduced from 500 mm to 175 mm. The above variations reduce the time duration for which gaseous nitrogen is delivered at temperature higher than 10.1°C (desired). Hence duty cycle reduces from eight hours to five hours. The other factors affecting performance such as fin configuration, fluid type, fluid pressure, intermittent flow nature and climatic conditions are assumed to be constant over the test duration. The decrement in outlet gas temperature (from 38 °C to 10.1°C) with corresponding increment in frost thickness leads to deterioration of performance of ambient air vaporizers.

  1. VOCS IN AMBIENT AIR NEAR WORLD TRADE CENTER SITE

    EPA Science Inventory

    Beginning on September 22, 2001 and continuing through February 2002, ambient air samples were collected at three sites within a block of ground zero and at a fourth site on the 16th floor of a building at 290 Broadway. Grab samples were collected in evacuated, electro-polished...

  2. 78 FR 19990 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards; Correction AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule... air quality standards in a new chapter of rules and adjusted the rule references accordingly...

  3. Colorado Air Quality Control Regulations and Ambient Air Quality Standards.

    ERIC Educational Resources Information Center

    Colorado State Dept. of Health, Denver. Div. of Air Pollution Control.

    Regulations and standards relative to air quality control in Colorado are defined in this publication. Presented first are definitions of terms, a statement of intent, and general provisions applicable to all emission control regulations adopted by the Colorado Air Pollution Control Commission. Following this, three regulations are enumerated: (1)…

  4. Air turbo-ramjet engine

    SciTech Connect

    Kepler, C.E.

    1991-12-24

    This patent describes a jet engine capable of being used to power an aircraft throughout a range of speeds from subsonic to high supersonic. It comprises means for bounding an internal passage centered on an axis and including, in succession as considered in the direction of axial flow of incoming air into and through the passage, a fixed-area air inlet section, a diverging passage section, a mixing section, a combustion section, and an outlet section; fan means situated in the air inlet section and including a rotor mounted in the bounding means for rotation about the axis and including a plurality of circumferentially spaced rotor blade members; means for selectively rotating the rotor about the axis with attendant impelling action of the rotor blade members on the air flowing therebetween; and means for selectively discharging air from a region of the passage situated between the air inlet section and the diverging passage section to the exterior of the bounding means, both at subsonic and supersonic speeds of the aircraft, when the amount of incoming air passing through the fixed-area inlet section exceeds that required in the combustion section.

  5. 78 FR 34964 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... for Ozone: State Implementation Plan Requirements AGENCY: Environmental Protection Agency (EPA... proposed rule ``Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State... proposed rulemaking proposes to implement the 2008 ozone national ambient air quality standards...

  6. BIOLOGICAL EFFECTS OF OIL FLY ASH AND RELEVANCE TO AMBIENT AIR PARTICULATE MATTER

    EPA Science Inventory

    Epidemiologic studies have demonstrated increased human morbidity and mortality with elevations in the concentration of ambient air particulate matter (PM). Fugitive fly ash from the combustion of oil and residual fuel oil significantly contributes to the ambient air particle bur...

  7. Air-Plasma Bullets Propagating Inside Microcapillaries and in Ambient Air

    NASA Astrophysics Data System (ADS)

    Lacoste, Deanna A.; Bourdon, Anne; Kuribara, Koichi; Urabe, Keiichiro; Stauss, Sven; Terashima, Kazuo

    2014-10-01

    We report on the characterization of air-plasma bullets formed inside microcapillary tubes and in ambient air, obtained without the use of inert or noble gases. The bullets are produced by nanosecond discharges, applied at 1 kHz in a dielectric barrier discharge configuration. The anode consists of a tungsten wire with a 50- μm diameter, centered in the microcapillary, while the cathode is a silver ring, fixed on the outer surface of the fused silica tube. The gap distance is kept constant at 1.35 mm. The microcapillary is fed with a 4-sccm flow of air at atmospheric pressure. In the tubes and in ambient air, the propagation of air plasma bullets is observed. The temporal evolution of the bullet propagation has been studied with the aid of an ICCD camera. The effect of the applied voltage (from 5.2 to 8.2 kV) and the inner diameter of the microcapillaries (from 100 to 500 μm) on the discharge dynamics are investigated. Inside the tubes, while the topology of the bullets seems to be strongly dependent on the diameter, their velocity (on the order of 1 to 5 ×105 ms-1) is only a function of the applied voltage. In ambient air, the air-plasma bullets propagate at a velocity of 1 . 25 ×105 ms-1. Possible mechanisms for the propagation of air-plasma bullets in ambient air are discussed.

  8. 77 FR 38760 - National Ambient Air Quality Standards for Particulate Matter; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... AGENCY 40 CFR Parts 50, 51, 52, 53, and 58 RIN 2060-AO47 National Ambient Air Quality Standards for... revise the national ambient air quality standards (NAAQS) for particulate matter (PM). This action...: Questions concerning the ``National Ambient Air Quality Standards for Particulate Matter'' proposed...

  9. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  10. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  11. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  12. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  13. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  14. 75 FR 2935 - Extension of Deadline for Promulgating Designations for the 2008 Ozone National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... Protection Agency 40 CFR Parts 50, 58 and 81 Ozone National Ambient Air Quality Standards; Final Rule and... Designations for the 2008 Ozone National Ambient Air Quality Standards AGENCY: Environmental Protection Agency... promulgating initial area designations for the ozone national ambient air quality standards (NAAQS) that...

  15. 77 FR 55832 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... monitoring ambient air quality. SUMMARY: Notice is hereby given that the Environmental Protection Agency (EPA... monitoring agencies under the requirements of 40 CFR part 58, Ambient Air Quality Surveillance. For such..., Ambient Air Quality Monitoring Program'' EPA-454/B-08-003, December, 2008. Provisions...

  16. Effects of Ambient Air Pollution Exposure on Olfaction: A Review

    PubMed Central

    Ajmani, Gaurav S.; Suh, Helen H.; Pinto, Jayant M.

    2016-01-01

    Background: Olfactory dysfunction affects millions of people worldwide. This sensory impairment is associated with neurodegenerative disease and significantly decreased quality of life. Exposure to airborne pollutants has been implicated in olfactory decline, likely due to the anatomic susceptibility of the olfactory nerve to the environment. Historically, studies have focused on occupational exposures, but more recent studies have considered effects from exposure to ambient air pollutants. Objectives: To examine all relevant human data evaluating a link between ambient pollution exposure and olfaction and to review supporting animal data in order to examine potential mechanisms for pollution-associated olfactory loss. Methods: We identified and reviewed relevant articles from 1950 to 2015 using PubMed and Web of Science and focusing on human epidemiologic and pathophysiologic studies. Animal studies were included only to support pertinent data on humans. We reviewed findings from these studies evaluating a relationship between environmental pollutant exposure and olfactory function. Results: We identified and reviewed 17 articles, with 1 additional article added from a bibliography search, for a total of 18 human studies. There is evidence in human epidemiologic and pathologic studies that increased exposure to ambient air pollutants is associated with olfactory dysfunction. However, most studies have used proxies for pollution exposure in small samples of convenience. Human pathologic studies, with supporting animal work, have also shown that air pollution can contact the olfactory epithelium, translocate to the olfactory bulb, and migrate to the olfactory cortex. Pollutants can deposit at each location, causing direct damage and disruption of tissue morphology or inducing local inflammation and cellular stress responses. Conclusions: Ambient air pollution may impact human olfactory function. Additional studies are needed to examine air pollution

  17. 76 FR 76048 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-06

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 81 RIN 2060-AR17 Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards Correction In rule document 2011-29460 appearing on pages 72097-72120 in the issues...

  18. Ambient Air Sampling During Quantum-dot Spray Deposition

    SciTech Connect

    Jankovic, John Timothy; Hollenbeck, Scott M

    2010-01-01

    Ambient air sampling for nano-size particle emissions was performed during spot spray coating operations with a Sono-Tek Exactacoat Benchtop system (ECB). The ECB consisted of the application equipment contained within an exhaust enclosure. The enclosure contained numerous small access openings, including an exhaust hook-up. Door access comprised most of the width and height of the front. The door itself was of the swing-out type. Two types of nanomaterials, Cadmium selenide (Cd-Se) quantum-dots (QDs) and Gold (Au) QDs, nominally 3.3 and 5 nm in diameter respectively, were applied during the evaluation. Median spray drop size was in the 20 to 60 micrometer size range.1 Surface coating tests were of short duration, on the order of one-half second per spray and ten spray applications between door openings. The enclosure was ventilated by connection to a high efficiency particulate aerosol (HEPA) filtered house exhaust system. The exhaust rate was nominally 80 ft3 per minute producing about 5 air changes per minute. Real time air monitoring with a scanning mobility particle size analyzer (SMPS ) with a size detection limit of 7 nm indicated a significant increase in the ambient air concentration upon early door opening. A handheld condensation particle counter (CPC) with a lower size limit of 10 nm did not record changes in the ambient background. This increase in the ambient was not observed when door opening was delayed for 2 minutes (~10 air changes). The ventilated enclosure controlled emissions except for cases of rapid door opening before the overspray could be removed by the exhaust. A time delay sufficient to provide 10 enclosure air changes (a concentration reduction of more than 99.99 %) before door opening prevented the release of aerosol particles in any size.2 Scanning-transmission electron microscopy (STEM) and atomic force microscopy (AFM) demonstrated the presence of agglomerates in the surfaces of the spray applied deposition. A filtered air sample of

  19. 77 FR 65310 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... AGENCY 40 CFR Part 81 Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Supplemental... particle (PM 2.5 ) national ambient air quality standards (NAAQS) air quality designations for the...

  20. Method for measurement of volatile oxygenated hydrocarbons in ambient air

    NASA Astrophysics Data System (ADS)

    Leibrock, E.; Slemr, J.

    An automated gas chromatographic method for the quantitative determination of oxygenated (C 2C 5 carbonyls and C 1C 2 alcohols) and some non-oxygenated (C 5C 8) hydrocarbons in ambient air has been developed. The analytical system consists of a gas chromatograph with a cryogenic sampling trap, a precolumn for the separation of water and other interfering compounds, a cryogenic focusing trap and two analytical columns connected in series. Substances are detected either by flame ionization or by a mass spectrometer. Ozone is removed by a potassium iodide scrubber placed upstream the sampling trap. External gas standards generated by a permeation device are used for calibration. The detection limits range between 0.03 and 0.08 ng (depending on the compound), equivalent to 5 to 56 ppt in 1 l of sampled air. The method was tested by an intercomparison with a different gas chromatographic technique for the determination of NMHC. The system has been applied since 1994 for measurements in ambient air. Data obtained during an intensive campaign in summer 1995 at the field station Wank (1778 m a.s.l.) near Garmisch-Partenkirchen, Germany, are reported and compared with NMHC mixing ratios measured simultaneously in the same air masses.

  1. Ambient and Emission Trends of Toxic Air Contaminants in California.

    PubMed

    Propper, Ralph; Wong, Patrick; Bui, Son; Austin, Jeff; Vance, William; Alvarado, Álvaro; Croes, Bart; Luo, Dongmin

    2015-10-06

    After initiating a toxic air contaminant (TAC) identification and control program in 1984, the California Air Resources Board adopted regulations to reduce TAC emissions from cars, trucks, stationary sources, and consumer products. This study quantifies ambient concentration and emission trends for the period 1990-2012 for seven TACs that are responsible for most of the known cancer risk associated with airborne exposure in California. Of these seven, diesel particulate matter (DPM) is the most important; however DPM is not measured directly. Based on a novel surrogate method, DPM concentrations declined 68%, even though the state's population increased 31%, diesel vehicle-miles-traveled increased 81%, and the gross state product (GSP) increased 74%. Based on monitoring data, concentrations of benzene, 1,3-butadiene, perchloroethylene, and hexavalent chromium declined 88-94%. Also, the ambient and emissions trends for each of these four TACs were similar. Furthermore, these declines generally occurred earlier in California than elsewhere. However, formaldehyde and acetaldehyde, which are formed in the air photochemically from volatile organic compounds (VOCs), declined only 20-21%. The collective cancer risk from exposure to these seven reviewed TACs declined 76%. Significant reduction in cancer risk to California residents from implementation of air toxics controls (especially for DPM) is expected to continue.

  2. Ambient air pollution and annoyance responses from pregnant women

    NASA Astrophysics Data System (ADS)

    Llop, Sabrina; Ballester, Ferran; Estarlich, Marisa; Esplugues, Ana; Fernández-Patier, Rosalia; Ramón, Rosa; Marco, Alfredo; Aguirre, Amelia; Sunyer, Jordi; Iñiguez, Carmen; INMA-Valencia cohort

    ObjectivesTo describe the degree of annoyance caused by air pollution and noise in pregnant women in a birth cohort; to determine the modifying factors and their relation with exposure to ambient nitrogen dioxide (NO 2). MethodsThe study population was 855 pregnant women in Valencia, Spain. Annoyance caused by air pollution and noise, and explanatory factors were obtained from 786 pregnant women through a questionnaire. NO 2 levels were determined combining measurements at 93 points within the area of study and using geostatistical techniques (kriging). ResultsIn all 7.9% of the women reported high annoyance caused by air pollution and 13.1% high annoyance caused by noise. There was a significant difference in the degree of annoyance due to both air pollution and noise depending on the area where the women lived and their working status. The degree of annoyance correlated better with measured NO 2 at the municipality level (air pollution: r=0.53; noise: r=0.44) than at the individual level (air pollution and noise: r=0.21). On multivariate analysis, being a housewife, higher NO 2 levels and high traffic density were associated with higher degrees of annoyance. ConclusionsThere was a high percentage of women who perceived medium-high annoyance due to noise and air pollution. Annoyance caused by environmental pollutants could lead to some psychological effects, which impair the quality of life, or even physiological ones, which affect prenatal development.

  3. Oxygen-selective immobilized liquid membranes for operation of lithium-air batteries in ambient air

    SciTech Connect

    Zhang, Jian; Xu, Wu; Liu, Wei

    2010-11-01

    In this paper, nonaqueous-electrolyte-based Li-air batteries with O2-selective immobilized liquid membranes have been developed and operated in ambient air with 20~30% relative humidity(RH). Continuous anhydrous O2 can be supplied from the ambient through a membrane barrier layer at interface of the cathode and ambient air. The membranes allow O2 permeate through while blocking moisture. These membranes were prepared by loading O2-selective liquid fluids such as silicone oils into porous supports such as porous metal sheets and Teflon (PTFE) films. It was found that silicone oil of high viscosity shows better performance. The membrane performance was not affected by the oil loading temperature. The immobilized silicone oil (viscosity 100,000cst) membrane in porous PTFE film enabled the Li-air batteries with Ketjen black carbon air electrodes to operate in ambient air (with 20% RH) for 16.3 days with a specific capacity of 789 mAh/g carbon and a specific energy of 2182 Wh/kg carbon. Its performance is much better than reference battery assembled with the same battery material but by use of a commercial, porous PTFE diffusion membranes as the moisture barrier layer on the cathode, which only had a discharge time of 5.5 days corresponding to a specific capacity of 267 mAh/g carbon and a specific energy of 704 Wh/kg carbon. The Li-air battery with the present selective membrane barrier layer even showed better performance in ambient air operation (20% RH) than the reference battery tested in the dry air box (< 1% RH).

  4. 75 FR 51039 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... for Air Pollution Measurement Systems, Volume I,'' EPA/600/R-94/038a and ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program'' EPA-454/B... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent...

  5. 77 FR 60985 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... for Air Pollution Measurement Systems, Volume I,'' EPA/600/R-94/038a and ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program'' EPA-454/B... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New...

  6. 76 FR 62402 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... for Air Pollution Measurement Systems, Volume I,'' EPA/600/R-94/038a and ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program,'' EPA-454/B... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent...

  7. The TOMPs ambient air monitoring network - Continuous data on UK air quality for over 20 years.

    PubMed

    Graf, Carola; Katsoyiannis, Athanasios; Jones, Kevin C; Sweetman, Andrew J

    2016-10-01

    Long-term air monitoring datasets are needed for persistent organic pollutants (POPs) to assess the effectiveness of source abatement measures and the factors controlling ambient levels. The Toxic Organic Micro Pollutants (TOMPs) Network, which has operated since 1991, collects ambient air samples at six sites across England and Scotland, using high-volume active air samplers. The network provides long-term ambient air trend data for a range of POPs at both urban and rural locations. Data from the network provides the UK Government, regulators and researchers with valuable information on emission/source controls and on the effectiveness of international chemicals regulation such as the Stockholm Convention and UN/ECE Protocol on POPs. The target chemicals of TOMPs have been polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and, since 2010, polybrominated diphenyl ethers (PBDEs). The continuous monitoring of these compounds demonstrates the constant decline in UK air concentrations over the last two decades, with average clearance rates for PCDD/Fs in urban locations of 5.1 years and for PCBs across all sites 6.6 years. No significant declines in rural locations for PCDD/Fs have been observed. There is a strong observable link between the declining ambient air concentrations and the emission reductions estimated in the annually produced National Atmospheric Emission Inventory (NAEI) dataset. These findings clearly demonstrate the unique strengths of long-term consistent datasets for the evaluation of the success of chemical regulation and control.

  8. Joint Effects of Ambient Air Pollutants on Pediatric Asthma ...

    EPA Pesticide Factsheets

    Background: Because ambient air pollution exposure occurs in the form of mixtures, consideration of joint effects of multiple pollutants may advance our understanding of air pollution health effects. Methods: We assessed the joint effect of selected ambient air pollutant combinations (groups of oxidant, secondary, traffic, power plant, and criteria pollutants constructed using combinations of criteria gases, fine particulate matter (PM2.5) and PM2.5 components) on warm season pediatric asthma emergency department (ED) visits in Atlanta during 1998-2004. Joint effects were assessed using multi-pollutant Poisson generalized linear models controlling for time trends, meteorology and daily non-asthma respiratory ED visit counts. Rate ratios (RR) were calculated for the combined effect of an interquartile-range increment in the concentration of each pollutant. Results: Increases in all of the selected pollutant combinations were associated with increases in pediatric asthma ED visits [e.g., joint effect rate ratio=1.13 (95% confidence interval 1.06-1.21) for criteria pollutants (including ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and PM2.5)]. Joint effect estimates were smaller than estimates calculated based on summing results from single-pollutant models, due to control for confounding. Compared with models without interactions, joint effect estimates from models including first-order pollutant interactions were similar for oxidant a

  9. Determination of beryllium concentrations in UK ambient air

    NASA Astrophysics Data System (ADS)

    Goddard, Sharon L.; Brown, Richard J. C.; Ghatora, Baljit K.

    2016-12-01

    Air quality monitoring of ambient air is essential to minimise the exposure of the general population to toxic substances such as heavy metals, and thus the health risks associated with them. In the UK, ambient air is already monitored under the UK Heavy Metals Monitoring Network for a number of heavy metals, including nickel (Ni), arsenic (As), cadmium (Cd) and lead (Pb) to ensure compliance with legislative limits. However, the UK Expert Panel on Air Quality Standards (EPAQS) has highlighted a need to limit concentrations of beryllium (Be) in air, which is not currently monitored, because of its toxicity. The aim of this work was to analyse airborne particulate matter (PM) sampled onto filter papers from the UK Heavy Metals Monitoring Network for quantitative, trace level beryllium determination and compare the results to the guideline concentration specified by EPAQS. Samples were prepared by microwave acid digestion in a matrix of 2% sulphuric acid and 14% nitric acid, verified by the use of Certified Reference Materials (CRMs). The digested samples were then analysed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The filters from the UK Heavy Metals Monitoring Network were tested using this procedure and the average beryllium concentration across the network for the duration of the study period was 7.87 pg m-3. The highest site average concentration was 32.0 pg m-3 at Scunthorpe Low Santon, which is significantly lower than levels that are thought to cause harm. However the highest levels were observed at sites monitoring industrial point sources, indicating that beryllium is being used and emitted, albeit at very low levels, from these point sources. Comparison with other metals concentrations and data from the UK National Atmospheric Emissions Inventory suggests that current emissions of beryllium may be significantly overestimated.

  10. Spectral fingerprinting of polycyclic aromatic hydrocarbons in high-volume ambient air samples by constant energy synchronous luminescence spectroscopy

    USGS Publications Warehouse

    Kerkhoff, M.J.; Lee, T.M.; Allen, E.R.; Lundgren, D.A.; Winefordner, J.D.

    1985-01-01

    A high-volume sampler fitted with a glass-fiber filter and backed by polyurethane foam (PUF) was employed to collect airborne particulate and gas-phase polycylic aromatic hydrocarbons (PAHs) in ambient air. Samples were collected from four sources representing a range of environmental conditions: gasoline engine exhaust, diesel engine exhaust, air near a heavily traveled interstate site, and air from a moderately polluted urban site. Spectral fingerprints of the unseparated particulate and gas-phase samples were obtained by constant energy synchronous luminescence spectroscopy (CESLS). Five major PAHs in the gas-phase extracts were characterized and estimated. The compatibility of a high-volume sampling method using polyurethane foam coupled with CESLS detection is explored for use as a screening technique for PAHs in ambient air. ?? 1985 American Chemical Society.

  11. Respiratory health effects of ambient air pollution: an update.

    PubMed

    Sava, Francesco; Carlsten, Chris

    2012-12-01

    There is new evidence for ambient air pollution (AAP) leading to an increased incidence of respiratory diseases in adults. Research has demonstrated that co-exposures have the potential to dramatically augment the effects of AAP and lower the threshold of effect of a given pollutant. Interactions between genes related to oxidative stress and AAP seem to significantly alter the effect of AAP on an individual and population basis. A better definition of vulnerable populations may bolster local or regional efforts to remediate AAP. Advances in genetic research tools have the potential to identify candidate genes that can guide further research.

  12. Ambient air pollution, climate change, and population health in China.

    PubMed

    Kan, Haidong; Chen, Renjie; Tong, Shilu

    2012-07-01

    As the largest developing country, China has been changing rapidly over the last three decades and its economic expansion is largely driven by the use of fossil fuels, which leads to a dramatic increase in emissions of both ambient air pollutants and greenhouse gases (GHGs). China is now facing the worst air pollution problem in the world, and is also the largest emitter of carbon dioxide. A number of epidemiological studies on air pollution and population health have been conducted in China, using time-series, case-crossover, cross-sectional, cohort, panel or intervention designs. The increased health risks observed among Chinese population are somewhat lower in magnitude, per amount of pollution, than the risks found in developed countries. However, the importance of these increased health risks is greater than that in North America or Europe, because the levels of air pollution in China are very high in general and Chinese population accounts for more than one fourth of the world's totals. Meanwhile, evidence is mounting that climate change has already affected human health directly and indirectly in China, including mortality from extreme weather events; changes in air and water quality; and changes in the ecology of infectious diseases. If China acts to reduce the combustion of fossil fuels and the resultant air pollution, it will reap not only the health benefits associated with improvement of air quality but also the reduced GHG emissions. Consideration of the health impact of air pollution and climate change can help the Chinese government move forward towards sustainable development with appropriate urgency.

  13. PREDICTING THE IMPACT OF TROPOSPHERIC OZONE ON ECOLOGICAL RESOURCES FOR SETTING NATIONAL AMBIENT AIR QUALITY STANDARDS

    EPA Science Inventory

    The Clean Air Act provides for establishing National Ambient Air Quality Standards (NAAQS) to protect public welfare (including crops, forests, ecosystems, and soils) from adverrse effects of air pollutants, including tropospheric ozone. The formulation of policies is science-bas...

  14. Characterization of ambient air pollution for stochastic health models

    SciTech Connect

    Batterman, S.A.

    1981-08-01

    This research is an analysis of various measures of ambient air pollution useful in cross-sectional epidemiological investigations and rick assessments. The Chestnut Ridge area health effects investigation, which includes a cross-sectional study of respiratory symptoms in young children, is used as a case study. Four large coal-fired electric generating power plants are the dominant pollution sources in this area of western Pennsylvania. The air pollution data base includes four years of sulfur dioxide and five years of total suspended particulate concentrations at seventeen monitors. Some 70 different characterizations of pollution are constructed and tested. These include pollutant concentrations at various percentiles and averaging times, exceedence measures which show the amount of time a specified threshold concentration is exceeded, and several dosage measures which transform non-linear dose-response relationships onto pollutant concentrations.

  15. Moisture swing sorbent for carbon dioxide capture from ambient air.

    PubMed

    Wang, Tao; Lackner, Klaus S; Wright, Allen

    2011-08-01

    An amine-based anion exchange resin dispersed in a flat sheet of polypropylene was prepared in alkaline forms so that it would capture carbon dioxide from air. The resin, with quaternary ammonium cations attached to the polymer structure and hydroxide or carbonate groups as mobile counterions, absorbs carbon dioxide when dry and releases it when wet. In ambient air, the moist resin dries spontaneously and subsequently absorbs carbon dioxide. This constitutes a moisture induced cycle, which stands in contrast to thermal pressure swing based cycles. This paper aims to determine the isothermal performance of the sorbent during such a moisture swing. Equilibrium experiments show that the absorption and desorption process can be described well by a Langmuir isothermal model. The equilibrium partial pressure of carbon dioxide over the resin at a given loading state can be increased by 2 orders of magnitude by wetting the resin.

  16. Engine bleed air reduction in DC-10

    NASA Technical Reports Server (NTRS)

    Newman, W. H.; Viele, M. R.

    1980-01-01

    An 0.8 percent fuel savings was achieved by a reduction in engine bleed air through the use of cabin air recirculation. The recirculation system was evaluated in revenue service on a DC-10. The cabin remained comfortable with reductions in cabin fresh air (engine bleed air) as much as 50 percent. Flight test verified the predicted fuel saving of 0.8 percent.

  17. The State of Ambient Air Quality of Jeddah, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Hussain, M. M.; Aburizaiza, O. S.; Khwaja, H. A.; Siddique, A.; Nayebare, S. R.; Zeb, J.; Blake, D. R.

    2014-12-01

    Ambient air pollution in major cities of Saudi Arabia is a substantial environmental and health concern. A study was undertaken to assess the air quality of Jeddah, Saudi Arabia by the analysis of respirable particulate matter (PM2.5), black carbon (BC), trace metals (Na, Mg, Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr, Cd, Sb, and Pb), and water-soluble ions (F-, Cl-, NO3-, SO42-, C2O42-, and NH42+). Sulfur and BC mass concentration ranged 0.99 - 7.39 μg/m3 and 0.70 - 3.09 μg/m3, respectively, while the PM2.5 mass concentration ranged 23 - 186 μg/m3. Maximum BC contribution to PM2.5 was 5.6%. Atmospheric PM2.5 concentrations were well above the 24 h WHO guideline of 20 μg/m3. Air Quality Index (AQI) indicates that there were 8% days of moderate air quality, 28% days of unhealthy air quality for sensitive groups, 55% days of unhealthy air quality, and 9% days of very unhealthy air quality during the study period. Sulfate SO42- dominated the identifiable components. The major contributors to PM2.5 were soil and crustal material; vehicle emissions (black carbon factor); and fuel oil combustion in industries (sulfur factor), according to the Positive Matrix Factorization (PMF). This study highlights the importance of focusing control strategies not only on reducing PM concentration, but also on the reduction of toxic components of the PM, to most effectively protect human health and the environment.

  18. Pure air-plasma bullets propagating inside microcapillaries and in ambient air

    NASA Astrophysics Data System (ADS)

    Lacoste, Deanna A.; Bourdon, Anne; Kuribara, Koichi; Urabe, Keiichiro; Stauss, Sven; Terashima, Kazuo

    2014-12-01

    This paper reports on the characterization of air-plasma bullets in microcapillary tubes and in ambient air, obtained without the use of inert or noble gases. The bullets were produced by nanosecond repetitively pulsed discharges, applied in a dielectric barrier discharge configuration. The anode was a tungsten wire with a diameter of 50 µm, centered in the microcapillary, while the cathode was a silver ring, fixed on the outer surface of the fused silica tube. The effects of the applied voltage and the inner diameter of the microcapillary tube on the plasma behavior were investigated. Inside the tubes, while the topology of the bullets seems to be strongly dependent on the diameter, their velocity is only a function of the amplitude of the applied voltage. In ambient air, the propagation of air bullets with a velocity of about 1.25 × 105 m s-1 is observed.

  19. An isotopic dilution approach for 1,3-butadiene tailpipe emissions and ambient air monitoring.

    PubMed

    Riservato, Manuela; Rolla, Antonio; Davoli, Enrico

    2004-01-01

    An isotopic dilution approach for 1,3-butadiene analysis in gaseous samples is presented. The methodology is based on active sampling on sorbent tubes and subsequent analysis by thermal desorption into a gas chromatography/mass spectrometry system. By adding a perdeuterated internal standard onto the sorbent tubes before sampling, and using mass spectrometric detection, the methodology gives high accuracy for this unstable analyte. The method has been used to monitor 1,3-butadiene ambient air concentrations in a residential area in proximity to a heavy-traffic roadway over a one-week period, for comparison with other traffic-related pollutants analysed by standard procedures. It has also been used to determine tailpipe emissions of two vehicles by standard emission testing procedures in a dynamometer. These vehicles were chosen as examples of low- and high-end emission rate vehicles, i.e., an old no-catalytic converter Otto engine and a new direct-injection diesel engine with catalytic converter. Exhaust gas emissions were 0.052 and 35.85 mg/km, reflecting differences in fuel, engine design, age, and presence (or not) of a catalytic abatement system. The ambient air results showed a weekly average concentration of 1,3-butadiene of 0.53 microg/m(3).

  20. Determination of methane in ambient air by multiplex gas chromatography

    NASA Technical Reports Server (NTRS)

    Valentin, J. R.; Carle, G. C.; Phillips, J. B.

    1985-01-01

    A multiplex gas chromatographic technique for the determination of methane in ambient air over extended periods is reported. A modest gas chromatograph which uses air as the carrier gas was modified by adding a silver oxide sample modulator for multiplex operation. The modulator selectively catalyzes the decomposition of methane in air. The resulting analytical system requires no consumables beyond power. A profile of the methane concentration in this laboratory was obtained for an 8-day period. During this period, methane concentration varied with an approximately daily period from a low of 1.53 + or - 0.60 ppm to a high of 4.63 + or - 0.59 ppm over the entire 8 days. Some of the measured concentrations are higher than those reported elsewhere indicating the presence of some local source or sources for methane. This work has demonstrated the utility of a relatively simple multiplex gas chromatograph for the analysis of environmental samples. The technique should be applicable to other trace components in air through use of other selective modulators.

  1. 75 FR 6473 - Primary National Ambient Air Quality Standards for Nitrogen Dioxide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... Protection Agency 40 CFR Parts 50 and 58 Primary National Ambient Air Quality Standards for Nitrogen Dioxide... Ambient Air Quality Standards for Nitrogen Dioxide AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: Based on its review of the air quality criteria for oxides of nitrogen and...

  2. 40 CFR 50.16 - National primary and secondary ambient air quality standards for lead.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for lead. 50.16 Section 50.16 Protection of Environment ENVIRONMENTAL PROTECTION... National primary and secondary ambient air quality standards for lead. (a) The national primary and secondary ambient air quality standards for lead (Pb) and its compounds are 0.15 micrograms per cubic...

  3. 40 CFR 50.12 - National primary and secondary ambient air quality standards for lead.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for lead. 50.12 Section 50.12 Protection of Environment ENVIRONMENTAL PROTECTION... National primary and secondary ambient air quality standards for lead. (a) National primary and secondary ambient air quality standards for lead and its compounds, measured as elemental lead by a reference...

  4. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  5. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  6. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  7. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  8. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  9. Dry deposition of polycyclic aromatic hydrocarbons in ambient air

    SciTech Connect

    Sheu, H.L.; Lee, W.J.; Su, C.C.; Chao, H.R.; Fan, Y.C.

    1996-12-01

    Dry deposition and air sampling were undertaken, simultaneously, in the ambient air of an urban site and a petrochemical-industry (PCI) plant by using several dry deposition plates and PS-1 samplers from January to May 1994 in southern Taiwan. The dry deposition plate with a smooth surface was always pointed into the wind. Twenty-one polycyclic aromatic hydrocarbons (PAHs) were analyzed by a gas chromatography/mass spectrometer (GC/MSD). The dry deposition flux of total-PAHs in urban and PCI sites averaged 166 and 211 {micro}g/m{sup 2}{center_dot}d, respectively. In general, the PAH dry deposition flux increased with increases in the PAH concentration in the ambient air. The PAH pattern of dry deposition flux in both urban and PCI sites were similar to the pattern measured by the filter of the PS-1 sampler and completely different from the PAH pattern in the gas phase. The higher molecular weight PAHs have higher dry deposition velocities. This is due to the fact that higher molecular weight PAHs primarily associated with the particle phase are deposited mostly by gravitational settling, while the gas phase PAHs were between 0.001 and 0.010 cm/s, only the lower molecular-weight PAHs--Nap and AcPy--had a significant fraction of dry deposition flux contributed by the gas phase. All the remaining higher molecular-weight PAHs had more than 94.5% of their dry deposition flux resulting from the particle phase. This is due to the fact that higher molecular weight PAHs have a greater fraction in the particle phase and the dry deposition velocities of particulates are much higher than those of the gas phase.

  10. Survey of Ambient Air Pollution Health Risk Assessment Tools.

    PubMed

    Anenberg, Susan C; Belova, Anna; Brandt, Jørgen; Fann, Neal; Greco, Sue; Guttikunda, Sarath; Heroux, Marie-Eve; Hurley, Fintan; Krzyzanowski, Michal; Medina, Sylvia; Miller, Brian; Pandey, Kiran; Roos, Joachim; Van Dingenen, Rita

    2016-09-01

    Designing air quality policies that improve public health can benefit from information about air pollution health risks and impacts, which include respiratory and cardiovascular diseases and premature death. Several computer-based tools help automate air pollution health impact assessments and are being used for a variety of contexts. Expanding information gathered for a May 2014 World Health Organization expert meeting, we survey 12 multinational air pollution health impact assessment tools, categorize them according to key technical and operational characteristics, and identify limitations and challenges. Key characteristics include spatial resolution, pollutants and health effect outcomes evaluated, and method for characterizing population exposure, as well as tool format, accessibility, complexity, and degree of peer review and application in policy contexts. While many of the tools use common data sources for concentration-response associations, population, and baseline mortality rates, they vary in the exposure information source, format, and degree of technical complexity. We find that there is an important tradeoff between technical refinement and accessibility for a broad range of applications. Analysts should apply tools that provide the appropriate geographic scope, resolution, and maximum degree of technical rigor for the intended assessment, within resources constraints. A systematic intercomparison of the tools' inputs, assumptions, calculations, and results would be helpful to determine the appropriateness of each for different types of assessment. Future work would benefit from accounting for multiple uncertainty sources and integrating ambient air pollution health impact assessment tools with those addressing other related health risks (e.g., smoking, indoor pollution, climate change, vehicle accidents, physical activity).

  11. Interlaboratory study of toxaphene analysis in ambient air

    NASA Astrophysics Data System (ADS)

    Bidleman, Terry F.; Cussion, Sylvia; Jantunen, Liisa M.

    An interlaboratory study was conducted for total toxaphene and selected congeners in an extract of ambient air from the southern United States. All participating labs were experienced in toxaphene analysis and used GC-MS techniques. Ten labs reported the concentration of total toxaphene in a technical toxaphene solution, with a 113% average recovery of the target value and 40% relative standard deviation (RSD). Only six of the 10 labs fell within ±30% of the target value, a criterion recommended by good laboratory practice standards. The interlaboratory RSD was 65% for total toxaphene in the air sample extract (lowered to 43% when one outlying lab was omitted). Nine labs reported the concentrations of five toxaphene components (B8-1413, B8-1414+B8-1945, B8-806+B8-809, B8-2229 and B9-1679) with 33-47% RSD for the technical toxaphene unknown and 34-62% for the air sample. The precision was poorer for a sixth component, congener B9-1025, which has a very low response by electron capture negative ion mass spectrometry (ECNI): 59% RSD for the technical toxaphene unknown and 196% for the air sample. Factors contributing to the interlaboratory variability for total toxaphene and single components are discussed, and follow-up studies are required to identify and minimize the causes of variability. Based on the average analysis, B8-1413 was enriched and B8-806+B8-809 was depleted in the air sample relative to the technical toxaphene standard.

  12. Femtosecond laser ablation of polytetrafluoroethylene (Teflon) in ambient air

    NASA Astrophysics Data System (ADS)

    Wang, Z. B.; Hong, M. H.; Lu, Y. F.; Wu, D. J.; Lan, B.; Chong, T. C.

    2003-05-01

    Teflon, polytetrafluorethylene (PTFE), is an important material in bioscience and medical application due to its special characteristics (bio-compatible, nonflammable, antiadhesive, and heat resistant). The advantages of ultrashort laser processing of Teflon include a minimal thermal penetration region and low processing temperatures, precision removal of material, and good-quality feature definition. In this paper, laser processing of PTFE in ambient air by a Ti:sapphire femtosecond laser (780 nm, 110 fs) is investigated. It is found that the pulse number on each irradiated surface area must be large enough for a clear edge definition and the ablated depth increases with the pulse number. The air ionization effect at high laser fluences not only degrades the ablated structures quality but also reduces the ablation efficiency. High quality microstructures are demonstrated with controlling laser fluence below a critical fluence to exclude the air ionization effect. The ablated microstructures show strong adhesion property to liquids and clear edges that are suitable for bio-implantation applications. Theoretical calculation is used to analyze the evolution of the ablated width and depth at various laser fluences.

  13. Joint Effects of Ambient Air Pollutants on Pediatric Asthma Emergency Department Visits in Atlanta, 1998–2004

    EPA Science Inventory

    Background: Because ambient air pollution exposure occurs in the form of mixtures, consideration of joint effects of multiple pollutants may advance our understanding of air pollution health effects. Methods: We assessed the joint effect of selected ambient air pollutant com...

  14. Collection of ambient air phenols using an anion exchange membrane

    SciTech Connect

    Nishioka, M.; Burkholder, H.; Reynolds, S.; Burdick, N.; Pleil, J.

    1994-12-31

    The authors have previously demonstrated the feasibility of collecting vapor phase ambient air phenols by reversible chemical reaction with a solid sorbent. The authors report here enhanced detection limits for ambient phenols using an anion exchange membrane that allows high collection efficiency at 10 L/min sampling rate. The membrane consists of 5 {micro}m particles of the anion exchange resin enmeshed in a Teflon microfibril matrix. This membrane is similar to Empore membranes, with the addition of the anion exchange capacity. Sampling is accomplished using a 10.5 cm (diameter) membrane and a General Metal Works PS-1 sampler. A Teflon-coated glass fiber filter, spiked with deutered phenols, and placed ahead of the membrane, is used to deliver these surrogate recovery standards to the membrane during the sampling. Following sampling, membranes are shaken gently in an acidified mixture of methanol and dichloromethane. The extract is derivatized with BSTFA and analyzed using either GC/FID or EI GC/MS. Analytical methodology allows detection at the 0.02 ppbv level for 12 hrs of sampling ({approximately} 0.1 {micro}g/m{sup 3}).

  15. Chemical transformations during ambient air sampling for organic vapors

    SciTech Connect

    Pellizzari, E.D.; Drost, K.J.

    1984-09-01

    Potential chemical transformations of olefins in the presence of ozone and high levels (ppm) of halogens (Cl/sub 2/, Br/sub 2/) were demonstrated when sampling ambient air with a sorbent cartridge. The use of stryene-d/sub 8/ and cyclohexene-d/sub 10/ spiked sampling devices and capillary gas chromatography/mass spectrometry (GC/MS) analysis allowed the detection and identification of several deuteriated oxidation and halogenated products. Dimethylamine-d/sub 6/ was converted in trace quantities (5-10 mg) to dimethylnitrosamine-d/sub 6/ when sampling was conducted in the presence of NO/sub x/. Oxidation reactions were prevented when filters (2.5 cm) employed for removing particulates were impregnated with 5-10 mg of sodium thiosulfate and placed in front of the sorbent cartridge. Halogenation reactions were also consideraly reduced.

  16. Determination of ambient air hydrocarbons in 39 US cities

    SciTech Connect

    Seila, R.L.; Lonneman, W.A.

    1988-06-01

    Compliance with the NAAQS for ozone will require the reduction of non-methane organic carbon (NMOC). To this end, speciated hydrocarbons were determined for over 800 ambient air samples from 39 U.S. cities from 1984-1986. Samples were collected in stainless steel spheres on week days from 6 to 9 A.M. during June through September. C2 to C12 hydrocarbons were determined by capillary GC/FID with sample cryogenic preconcentration. The GC retention time identification table consisted of 314 uniquely numbered peaks, of which 97 were specifically named, 214 were identified by type (olefin, paraffin, aromatic). GC-MSD/FID analysis confirmed the identity of 40 peaks and indicated the presence of oxygenated, chlorinated, and fluorinated hydrocarbons in some samples.

  17. Volcanic gas emissions and their effect on ambient air character

    SciTech Connect

    Sutton, A.J.; Elias, T.

    1994-01-01

    This bibliography was assembled to service an agreement between Department of Energy and the USGS to provide a body of references and useful annotations for understanding background gas emissions from Kilauea volcano. The current East Rift Zone (ERZ) eruption of Kilauea releases as much as 500,000 metric tonnes of SO{sub 2} annually, along with lesser amounts of other chemically and radiatively active species including H{sub 2}S, HCl, and HF. Primary degassing locations on Kilauea are located in the summit caldera and along the middle ERZ. The effects of these emissions on ambient air character are a complex function of chemical reactivity, source geometry and effusivity, and local meteorology. Because of this complexity, we organized the bibliography into three main sections: (1) characterizing gases as they leave the edifice; (2) characterizing gases and chemical reaction products away from degassing sources; and (3) Hawaii Island meteorology.

  18. Artifact peroxides produced during cryogenic sampling of ambient air

    NASA Astrophysics Data System (ADS)

    Staffelbach, Thomas; Neftel, Albrecht; Dasgupta, Purnendu K.

    Peroxides were found to be produced as artifacts during cryogenic sampling with Horibe traps. Cryogenic trap sampling was compared to collection with a wet effluent diffusion denuder and a Nafion membrane diffusion denuder. Hydrogen peroxide and hydroxymethyl hydroperoxide measured in the cryogenic trap samples were significantly higher. In comparison, no evidence of artifact methyl hydroperoxide production was found. The amount of artifact H2O2 and HMHP produced increased with decreasing trap temperature. Spiking ambient air with ethene or isoprene showed that these hydrocarbons, in the presence of ozone, can be responsible for the artifact production of peroxides. Our results clearly suggest that the peroxide data obtained by cryogenic sampling and reported in the literature should be interpreted with caution.

  19. The Effect of Ambient Air Pollution on Sperm Quality

    PubMed Central

    Hansen, Craig; Luben, Thomas J.; Sacks, Jason D.; Olshan, Andrew; Jeffay, Susan; Strader, Lillian; Perreault, Sally D.

    2010-01-01

    Background Research has suggested an association with ambient air pollution and sperm quality. Objectives We investigated the effect of exposure to ozone (O3) and particulate matter < 2.5 μm in aerodynamic diameter (PM2.5) on sperm quality. Methods We reexamined a previous cohort study of water disinfection by-products to evaluate sperm quality in 228 presumed fertile men with different air pollution profiles. Outcomes included sperm concentration, total sperm per ejaculate (count), and morphology, as well as DNA integrity and chromatin maturity. Exposures to O3 and PM2.5 were evaluated for the 90–day period before sampling. We used multivariable linear regression, which included different levels of adjustment (i.e., without and with season and temperature) to assess the relationship between exposure to air pollutants during key periods of sperm development and adverse sperm outcomes. Results Sperm concentration and count were not associated with exposure to PM2.5, but there was evidence of an association (but not statistically significant) with O3 concentration and decreased sperm concentration and count. Additionally, a significant increase in the percentage of sperm cells with cytoplasmic drop [β = 2.64; 95% confidence interval (CI), 0.21–5.06] and abnormal head (β = 0.47; 95% CI, 0.03–0.92) was associated with PM2.5 concentration in the base model. However, these associations, along with all other sperm outcomes, were not significantly associated with either pollutant after controlling for season and temperature. Overall, although we found both protective and adverse effects, there was generally no consistent pattern of increased abnormal sperm quality with elevated exposure to O3 or PM2.5. Conclusions Exposures to O3 or PM2.5 at levels below the current National Ambient Air Quality Standards were not associated with statistically significant decrements in sperm outcomes in this cohort of fertile men. However, some results suggested effects on sperm

  20. A reversible long-life lithium-air battery in ambient air.

    PubMed

    Zhang, Tao; Zhou, Haoshen

    2013-01-01

    Electrolyte degradation, Li dendrite formation and parasitic reactions with H₂O and CO₂ are all directly correlated to reversibility and cycleability of Li-air batteries when operated in ambient air. Here we replace easily decomposable liquid electrolytes with a solid Li-ion conductor, which acts as both a catholyte and a Li protector. Meanwhile, the conventional solid air cathodes are replaced with a gel cathode, which contacts directly with the solid catholyte to form a closed and sustainable gel/solid interface. The proposed Li-air cell has sustained repeated cycling in ambient air for 100 cycles (~78 days), with discharge capacity of 2,000 mAh g(-1). The recharging is based largely on the reversible reactions of Li₂CO₃ product, originating from the initial discharge product of Li₂O₂ instead of electrolyte degradation. Our results demonstrate that a reversible long-life Li-air battery is attainable by coordinated approaches towards the focal issues of electrolytes and Li metal.

  1. Table of Historical Nitrogen Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    See the history of limits to the level of nitrogen dioxide (NO2) in ambient air, set through the NAAQS review and rulemaking process under the Clean Air Act. This includes both primary and secondary standards.

  2. HIGH VOLUME INJECTION FOR GCMS ANALYSIS OF PARTICULATE ORGANIC SPECIES IN AMBIENT AIR

    EPA Science Inventory

    Detection of organic species in ambient particulate matter typically requires large air sample volumes, frequently achieved by grouping samples into monthly composites. Decreasing the volume of air sample required would allow shorter collection times and more convenient sample c...

  3. Ambient air pollution particles and the acute exacerbation of chronic obstructive pulmonary disease

    EPA Science Inventory

    Investigation has repeatedly demonstrated an association between exposure to ambient air pollution particles and numerous indices of human morbidity and mortality. Individuals with chronic obstructive pulmonary disease (COPD) are among those with an increased sensitivity to air p...

  4. Development and Evaluation of Alternative Metrics of Ambient Air Pollution Exposure for Use in Epidemiologic Studies

    EPA Science Inventory

    Population-based epidemiologic studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available outdoor concentrations from central monitoring sites. This practice may in...

  5. Table of Historical Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    See the history of limits to the level of sulfur dioxide (SO2) in ambient air, set through the NAAQS review and rulemaking process under the Clean Air Act. This includes both primary and secondary standards.

  6. BOREAS TGB-7 Ambient Air Herbicide and Organochlorine Concentration Data

    NASA Technical Reports Server (NTRS)

    Waite, Don; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB)-7 team measured the concentration and flux of several agricultural pesticides in air, rainwater, and dry deposition samples in order to determine the associated yearly deposition rates. This data set contains information on the ambient air concentration of seven herbicides [2,4- dichlorophenoxyacidic_acid (2,4-D), bromoxynil, dicamb, 2-methyl-4-chlorophenoxyacetic acid (MCPA), triallate, trifluralin, and diclop-methyl] known to appear in the atmosphere of the Canadian prairies. Also, the concentration of three herbicides (atrazine, alachlor, and metolachlor), two groups of insecticides (lindane and breakdown products and dichloro-diphenyl-trichloroethane (DDT) and breakdown products), and several polychlorinated biphenyls commonly used in the central United States was measured. All of these chemicals are reported, in the literature, to be transported in the atmosphere. Many have been reported to occur in boreal and arctic food chains. The sampling was carried out from 16-Jun to 13-Aug-1993 and 04-May to 20-Jul-1994 at the BOREAS site in the Prince Albert National Park (Waskesiu). The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884).

  7. Heavy metal pollution of ambient air in Nagpur City.

    PubMed

    Chaudhari, Pramod R; Gupta, Rakhi; Gajghate, Daulat Ghilagi; Wate, Satish R

    2012-04-01

    Heavy metals released from different sources in urban environment get adsorbed on respirable particulate matter less than 10 μm in size (PM(10)) and are important from public health point of view causing morbidity and mortality. Therefore, the ambient air quality monitoring was carried out to study the temporal and special pattern in the distribution of PM(10) and associated heavy metal content in the atmosphere of Nagpur, Maharashtra State, India during 2001 as well as in 2006. PM(10) fraction was observed to exceed the stipulated standards in both years. It was also observed that minimum range of PM(10) was observed to be increased in 2006 indicating increase in human activity during nighttime also. Six heavy metals were analyzed and were observed to occur in the order Zn > Fe > Pb > Ni > Cd > Cr in 2006, similar to the trend in other metro cities in India. Lead and Nickel were observed to be within the stipulated standards. Poor correlation coefficient (R(2)) between lead and PM(10) indicated that automobile exhaust is not the source of metals to air pollution. Commercial and industrial activity as well as geological composition may be the potential sources of heavy metal pollution. Total load of heavy metals was found to be increased in 2006 with prominent increase in zinc, lead, and nickel in the environment. Public health impacts of heavy metals as well as certain preventive measures to mitigate the impact of heavy metals on public health are also summarized.

  8. Ambient Air Pollution and the Risk of Acute Ischemic Stroke

    PubMed Central

    Wellenius, Gregory A.; Burger, Mary R.; Coull, Brent A.; Schwartz, Joel; Suh, Helen H.; Koutrakis, Petros; Schlaug, Gottfried; Gold, Diane R.; Mittleman, Murray A.

    2013-01-01

    Background The link between daily changes in ambient fine particulate matter air pollution (PM2.5) and cardiovascular morbidity and mortality is well established. Whether PM2.5 at levels below current US National Ambient Air Quality Standards also increases the risk of ischemic stroke remains uncertain. Methods We reviewed the medical records of 1705 Boston-area patients hospitalized with neurologist-confirmed ischemic stroke and abstracted data on the time of symptom onset and clinical characteristics. PM2.5 concentrations were measured at a central monitoring station. We used the time-stratified case-crossover study design to assess the association between the risk of ischemic stroke onset and PM2.5 levels in the hours and days preceding each event. We examined whether the association with PM2.5 differed by ischemic stroke etiology and patient characteristics. Results The estimated odds ratio of ischemic stroke onset was 1.34 (95% confidence interval (CI): 1.13, 1.58; p<0.001) following a 24-hour period classified as “moderate” (PM2.5 15–40 μg/m3) by the US Environmental Protection Agency’s (EPA) Air Quality Index compared to a 24-hour period classified as “good” (≤15 μg/m3). Considering PM2.5 as a continuous variable, the estimated odds ratio of ischemic stroke onset was 1.11 (95% CI: 1.03, 1.20; p=0.006) per interquartile range increase in PM2.5 (6.4 μg/m3). The increase in risk was greatest within 12–14 hours of exposure to PM2.5 and was most strongly associated with markers of traffic-related pollution. Conclusion These results suggest that exposure to PM2.5 levels considered generally safe by the US EPA increase the risk of ischemic stroke onset within hours of exposure. PMID:22332153

  9. Ambient Air Pollution and Preeclampsia: A Spatiotemporal Analysis

    PubMed Central

    Figueras, Francesc; Basagaña, Xavier; Beelen, Rob; Martinez, David; Cirach, Marta; Schembari, Anna; Hoek, Gerard; Brunekreef, Bert; Nieuwenhuijsen, Mark J

    2013-01-01

    Background: Available evidence concerning the association between air pollution and preeclampsia is limited, and specific associations with early- and late-onset preeclampsia have not been assessed. Objectives: We investigated the association, if any, between preeclampsia (all, early-, and late-onset) and exposure to nitrogen dioxide, nitrogen oxides, particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5; fine particles), ≤ 10 μm, and 2.5–10 μm, and PM2.5 light absorption (a proxy for elemental carbon) during the entire pregnancy and during the first, second, and third trimesters. Methods: This study was based on 8,398 pregnancies (including 103 cases of preeclampsia) among women residing in Barcelona, Spain (2000–2005). We applied a spatiotemporal exposure assessment framework using land use regression models to predict ambient pollutant levels during each week of pregnancy at the geocoded residence address of each woman at the time of birth. Logistic and conditional logistic regression models were used to estimate unadjusted and adjusted associations. Results: We found positive associations for most of our evaluated outcome–exposure pairs, with the strongest associations observed for preeclampsia and late-onset preeclampsia in relation to the third-trimester exposure to fine particulate pollutants, and for early-onset preeclampsia in relation to the first-trimester exposure to fine particulate pollutants. Among our investigated associations, those of first- and third-trimester exposures to PM2.5 and third-trimester exposure to PM2.5 absorbance and all preeclampsia, and third-trimester PM2.5 exposure and late-onset preeclampsia attained statistical significance. Conclusion: We observed increased risk of preeclampsia associated with exposure to fine particulate air pollution. Our findings, in combination with previous evidence suggesting distinct pathogenic mechanisms for early- and late-onset preeclampsia, support additional research on this

  10. 40 CFR Appendix C to Part 58 - Ambient Air Quality Monitoring Methodology

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App. C Appendix C to Part 58—Ambient Air... specified in this section. 2.4.1.7Data transformations are allowed to be used to demonstrate meeting the comparability requirements specified in subpart C of part 53 of this chapter. Data transformation may be...

  11. 75 FR 45627 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-03

    ... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of one new equivalent method for monitoring ambient air quality. SUMMARY: Notice is hereby...

  12. Test/QA Plan (TQAP) for Verification of Semi-Continuous Ambient Air Monitoring Systems

    EPA Science Inventory

    The purpose of the semi-continuous ambient air monitoring technology (or MARGA) test and quality assurance plan is to specify procedures for a verification test applicable to commercial semi-continuous ambient air monitoring technologies. The purpose of the verification test is ...

  13. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  14. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  15. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  16. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  17. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  18. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.4 Section 50.4 Protection of Environment ENVIRONMENTAL....4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...). (c) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference...

  19. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  20. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.4 Section 50.4 Protection of Environment ENVIRONMENTAL....4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...). (c) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference...

  1. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.4 Section 50.4 Protection of Environment ENVIRONMENTAL....4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...). (c) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference...

  2. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.4 Section 50.4 Protection of Environment ENVIRONMENTAL....4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...). (c) Sulfur oxides shall be measured in the ambient air as sulfur dioxide by the reference...

  3. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  4. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  5. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  6. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  7. Evaluation of air quality zone classification methods based on ambient air concentration exposure.

    PubMed

    Freeman, Brian; McBean, Ed; Gharabaghi, Bahram; Thé, Jesse

    2017-05-01

    Air quality zones are used by regulatory authorities to implement ambient air standards in order to protect human health. Air quality measurements at discrete air monitoring stations are critical tools to determine whether an air quality zone complies with local air quality standards or is noncompliant. This study presents a novel approach for evaluation of air quality zone classification methods by breaking the concentration distribution of a pollutant measured at an air monitoring station into compliance and exceedance probability density functions (PDFs) and then using Monte Carlo analysis with the Central Limit Theorem to estimate long-term exposure. The purpose of this paper is to compare the risk associated with selecting one ambient air classification approach over another by testing the possible exposure an individual living within a zone may face. The chronic daily intake (CDI) is utilized to compare different pollutant exposures over the classification duration of 3 years between two classification methods. Historical data collected from air monitoring stations in Kuwait are used to build representative models of 1-hr NO2 and 8-hr O3 within a zone that meets the compliance requirements of each method. The first method, the "3 Strike" method, is a conservative approach based on a winner-take-all approach common with most compliance classification methods, while the second, the 99% Rule method, allows for more robust analyses and incorporates long-term trends. A Monte Carlo analysis is used to model the CDI for each pollutant and each method with the zone at a single station and with multiple stations. The model assumes that the zone is already in compliance with air quality standards over the 3 years under the different classification methodologies. The model shows that while the CDI of the two methods differs by 2.7% over the exposure period for the single station case, the large number of samples taken over the duration period impacts the sensitivity of

  8. Association of trends in US ambient air quality and cardiovascular mortality for 2000-2010

    EPA Science Inventory

    With the implementation of the Clean Air Act’s National Ambient Air Quality Standards, air quality in the United States has notably improved. Here we investigate whether declining levels of air pollutants are associated with improvements in human health. We examine the re...

  9. Combustion engine. [for air pollution control

    NASA Technical Reports Server (NTRS)

    Houseman, J. (Inventor)

    1977-01-01

    An arrangement for an internal combustion engine is provided in which one or more of the cylinders of the engine are used for generating hydrogen rich gases from hydrocarbon fuels, which gases are then mixed with air and injected into the remaining cylinders to be used as fuel. When heavy load conditions are encountered, hydrocarbon fuel may be mixed with the hydrogen rich gases and air and the mixture is then injected into the remaining cylinders as fuel.

  10. MetNH3: Metrology for ammonia in ambient air

    NASA Astrophysics Data System (ADS)

    Braban, Christine; Twigg, Marsailidh; Tang, Sim; Leuenberger, Daiana; Ferracci, Valerio; Martin, Nick; Pascale, Celine; Hieta, Tuomas; Pogany, Andrea; Persijn, Stefan; van Wijk, Janneke; Gerwig, Holger; Wirtze, Klaus; Tiebe, Carlo; Balslev-Harder, David; Niederhausen, Bernhardt

    2015-04-01

    Measuring ammonia in ambient air is a sensitive and priority issue due to its harmful effects on human health and ecosystems. The European Directive 2001/81/EC on 'National Emission Ceilings for Certain Atmospheric Pollutants (NEC)' regulates ammonia emissions in the member states. However, there is a lack of regulation to ensure reliable ammonia measurements namely in applicable analytical technology, maximum allowed uncertainty, quality assurance and quality control (QC/QA) procedures as well as in the infrastructure to attain metrological traceability. Validated ammonia measurement data of high quality from air monitoring networks are vitally important for identifying changes due to implementations of environment policies, for understanding where the uncertainties in current emission inventories are derived from and for providing independent verification of atmospheric model predictions. The new EURAMET project MetNH3 aims to develop improved reference gas mixtures by static and dynamic gravimetric generation methods, develop and characterise laser based optical spectrometric standards and establish the transfer from high-accuracy standards to field applicable methods. MetNH3started in June 2014 and in this presentation the first results from the metrological characterisation of a commercially available cavity ring-down spectrometer (CRDS) will be discussed. Also first tests and results from a new design, Controlled Atmosphere Test Facility (CATFAC), which is to be characterised and used to validate the performance of diffusive samplers, denuders and on-line instruments, will be reported. CAFTEC can be used to control test parameters such as ammonia concentration, relative humidity and wind speed. Outline plans for international laboratory and field intercomparisons in 2016 will be presented.

  11. ISS Ambient Air Quality: Updated Inventory of Known Aerosol Sources

    NASA Technical Reports Server (NTRS)

    Meyer, Marit

    2014-01-01

    Spacecraft cabin air quality is of fundamental importance to crew health, with concerns encompassing both gaseous contaminants and particulate matter. Little opportunity exists for direct measurement of aerosol concentrations on the International Space Station (ISS), however, an aerosol source model was developed for the purpose of filtration and ventilation systems design. This model has successfully been applied, however, since the initial effort, an increase in the number of crewmembers from 3 to 6 and new processes on board the ISS necessitate an updated aerosol inventory to accurately reflect the current ambient aerosol conditions. Results from recent analyses of dust samples from ISS, combined with a literature review provide new predicted aerosol emission rates in terms of size-segregated mass and number concentration. Some new aerosol sources have been considered and added to the existing array of materials. The goal of this work is to provide updated filtration model inputs which can verify that the current ISS filtration system is adequate and filter lifetime targets are met. This inventory of aerosol sources is applicable to other spacecraft, and becomes more important as NASA considers future long term exploration missions, which will preclude the opportunity for resupply of filtration products.

  12. ENGINEERING BULLETIN: AIR PATHWAY ANALYSIS

    EPA Science Inventory

    This bulletin presents information on estimating toxic air emissions from Superfund sites. The focus is on the collection of air emmissions data during the site inspection and remedial investigation/feasibility study and the use of these data for the selection or implementation o...

  13. 77 FR 39205 - Public Hearings for Proposed Rules-National Ambient Air Quality Standards for Particulate Matter

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Quality Standards for Particulate Matter AGENCY: Environmental Protection Agency (EPA). ACTION... titled, ``National Ambient Air Quality Standards for Particulate Matter,'' that is scheduled to be... and secondary national ambient air quality standards (NAAQS) for particulate matter (PM) to...

  14. FINE AMBIENT AIR PARTICULAR MATTER EXPOSURE INDUCES MOLECULAR ALTERATIONS INDICATIVE OF CARDIOVASCULAR DISEASE PROGRESSION IN ATHEROSCLEROTIC SUSCEPTIBLE MICE

    EPA Science Inventory

    Epidemiological, clinical, and toxicological studies have demonstrated that exposure to ambient air particulate matter (PM) can alter cardiovascular function and may influence cardiovascular disease (CVD). It has been shown that exposure to concentrated ambient air particles (CA...

  15. Panel discussion review: Session two - Interpretation of Observed Associations between Multiple Ambient Air Pollutants and Health Effects in Epidemiologic Analysis

    EPA Science Inventory

    Air pollution epidemiologic research has often utilized ambient air concentrations measured from centrally located monitors as a surrogate measure of exposure to these pollutants. Associations between these ambient concentrations and health outcomes such as lung function, hospita...

  16. 78 FR 47191 - Air Quality Designations for the 2010 Sulfur Dioxide (SO2) Primary National Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-05

    ... AGENCY 40 CFR Part 81 RIN 2060-AR18 Air Quality Designations for the 2010 Sulfur Dioxide (SO ) Primary National Ambient Air Quality Standard AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This rule establishes air quality designations for certain areas in the United States for...

  17. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  18. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  19. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  20. 40 CFR 1033.505 - Ambient conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air...

  1. 40 CFR 1033.505 - Ambient conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air...

  2. 40 CFR 1033.505 - Ambient conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air...

  3. 40 CFR 1033.505 - Ambient conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air...

  4. 40 CFR 1033.505 - Ambient conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air...

  5. Ambient Engineering for High-Performance Organic-Inorganic Perovskite Hybrid Solar Cells.

    PubMed

    Huang, Jiabin; Yu, Xuegong; Xie, Jiangsheng; Xu, Dikai; Tang, Zeguo; Cui, Can; Yang, Deren

    2016-08-24

    Considering the evaporation of solvents during fabrication of perovskite films, the organic ambience will present a significant influence on the morphologies and properties of perovskite films. To clarify this issue, various ambiences of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and chlorobenzene (CBZ) are introduced during fabrication of perovskite films by two-step sequential deposition method. The results reveal that an ambient CBZ atmosphere is favorable to control the nucleation and growth of CH3NH3PbI3 grains while the others present a negative effect. The statistical results show that the average efficiencies of perovskite solar cells processed in an ambient CBZ atmosphere can be significantly improved by a relatively average value of 35%, compared with those processed under air. The efficiency of the best perovskite solar cells can be improved from 10.65% to 14.55% by introducing this ambience engineering technology. The CH3NH3PbI3 film with large-size grains produced in an ambient CBZ atmosphere can effectively reduce the density of grain boundaries, and then the recombination centers for photoinduced carriers. Therefore, a higher short-circuit current density is achieved, which makes main contribution to the improvement in efficiency. These results provide vital progress toward understanding the role of ambience in the realization of highly efficient perovskite solar cells.

  6. 30 CFR 250.610 - Diesel engine air intakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.610 Section 250... engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines which are...

  7. 30 CFR 250.510 - Diesel engine air intakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.510 Section 250... engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that are continuously attended must be equipped...

  8. 30 CFR 250.510 - Diesel engine air intakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Diesel engine air intakes. 250.510 Section 250... Well-Completion Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that...

  9. 30 CFR 250.510 - Diesel engine air intakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Diesel engine air intakes. 250.510 Section 250... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that are continuously attended...

  10. 30 CFR 250.510 - Diesel engine air intakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Diesel engine air intakes. 250.510 Section 250... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that are continuously attended...

  11. 30 CFR 250.510 - Diesel engine air intakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Diesel engine air intakes. 250.510 Section 250... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that are continuously attended...

  12. Comparison of the genotoxic activities of extracts from ambient and forest fire polluted air. [Humans

    SciTech Connect

    Viau, C.J.; Lockard, J.M.; Enoch, H.G.; Sabharwal, P.S.

    1982-01-01

    The genotoxicity of airborne organic particles from forest fire smoke was compared to that from nonsmoky (ambient) urban air using the Salmonella reversion assay and the sister chromatid exchange (SCE) assay in cultured human lymphocytes. Salmonella strains TA98 and TA100 were used with and without the addition of Aroclor-induced rat liver homogenate (S9). Each sample induced dose-related increases in mutagenicity and SCE. However, on the basis of the volume of air sampled, the smoke-filled air induced 12 to 14 times more bacterial reversions in TA 100 and 16-38 times more reversion in TA98 than ambient air. Similarly, on a volume basis smoky air induced 43 times more SCE in human lymphocytes than did ambient air. The results indicate that the increased mutagenicity was due not only to the heavier particulate load of the air, but also to the increased specific mutagenicity of the particles.

  13. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... National Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) 1. General (a) This... national ambient air quality standards for oxides of nitrogen as measured by nitrogen dioxide (“NO2...

  14. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... National Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) 1. General (a) This... national ambient air quality standards for oxides of nitrogen as measured by nitrogen dioxide (“NO2...

  15. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... National Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) 1. General (a) This... national ambient air quality standards for oxides of nitrogen as measured by nitrogen dioxide (“NO2...

  16. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... National Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) 1. General (a) This... national ambient air quality standards for oxides of nitrogen as measured by nitrogen dioxide (“NO2...

  17. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  18. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  19. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  20. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  1. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  2. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  3. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  4. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  5. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  6. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  7. Effects of ambient oxidant air pollution in the San Joaquin Valley on Thompson seedless grapes

    SciTech Connect

    Brewer, R.F.; Ashcroft, R.

    1984-01-01

    Mature Thompson seedless grape vines were enclosed in specially constructed plastic covered chambers supplied with carbon filtered and non-filtered (ambient) air from time of bud break through leaf drop. Effects on vegetative growth and fruiting were determined for three seasons. No effects on fruit production were measured the first season after covering but vegetative growth increased 12% in chambers supplied with filtered air. By the third season fruit yields were 27.5% higher in the filtered as compared with ambient chambers. The only visible symptoms associated with exposure to the oxidants was accelerated senescence which appeared 3 weeks to 1 month earlier on vines receiving ambient or nonfiltered air.

  8. 75 FR 81477 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Amendments to Ambient...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia; Amendments to Ambient Air Quality Standards for Particulate Matter AGENCY: Environmental Protection Agency (EPA... quality standards for particulate matter (PM). This action is being taken under the Clean Air Act...

  9. 78 FR 3085 - National Ambient Air Quality Standards for Particulate Matter

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-15

    ... Air Quality Standards for Particulate Matter; Final Rule #0;#0;Federal Register / Vol. 78 , No. 10..., 51, 52, 53 and 58 RIN 2060-AO47 National Ambient Air Quality Standards for Particulate Matter AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: Based on its review of the air...

  10. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating..., within the test cell, during all phases of the air conditioning test sequence to 95 ±2 °F on average and... of 30 second intervals. Records of cell air temperatures and values of average test temperatures...

  11. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating..., within the test cell, during all phases of the air conditioning test sequence to 95 ±2 °F on average and... of 30 second intervals. Records of cell air temperatures and values of average test temperatures...

  12. Engineering with uncertainty: monitoring air bag performance.

    PubMed

    Wetmore, Jameson M

    2008-06-01

    Modern engineering is complicated by an enormous number of uncertainties. Engineers know a great deal about the material world and how it works. But due to the inherent limits of testing and the complexities of the world outside the lab, engineers will never be able to fully predict how their creations will behave. One way the uncertainties of engineering can be dealt with is by actively monitoring technologies once they have left the development and production stage. This article uses an episode in the history of automobile air bags as an example of engineers who had the foresight and initiative to carefully track the technology on the road to discover problems as early as possible. Not only can monitoring help engineers identify problems that surface in the field, it can also assist them in their efforts to mobilize resources to resolve problem.

  13. METHYL- AND DIMETHYL-/ETHYL-NITRONAPHTHALENES MEASURED IN AMBIENT AIR IN SOUTHERN CALIFORNIA. (R827352)

    EPA Science Inventory

    Naphthalene and alkylnaphthalenes are abundant semi-volatile polycyclic aromatic hydrocarbons (PAHs) present in ambient air as a result of emissions from combustion sources. At ambient temperatures, these PAHs can undergo atmospheric gas-phase reactions with hydroxyl (OH) radi...

  14. Type of wear for the pair Ti6Al4V/PCTFE in ambient air and in liquid nitrogen

    NASA Astrophysics Data System (ADS)

    Bozet, J.-L.

    1993-04-01

    The pair Ti6Al4V/polychlorotrifluoroethylene (PCTFE) on a pin-on-disk tribometer in ambient air and liquid nitrogen with the contact pressure and sliding speed ranging from 3 to 9 MPa and 0.03 to 0.05 m/s, respectively, is evaluated within the framework of a high pressure valves for cryogenic rocket engines project. Results show that an abrasion wear process, which is closely connected with a tribochemical wear process producing fluorides and an abrasive form of carbon, exists when PCTFE is continuously rubbed against Ti6Al4V in ambient air, liquid nitrogen, and gaseous argon. Degradations detected on the Ti6Al4V surface are found to be unacceptable in most cases, but in the real cryotechnic valves this type of wear was not observed. The latter is attributed to the great dwell time between actuations and the low speed of the reciprocating movements which considerably limit the heating.

  15. 75 FR 22126 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    .... Environmental Protection Agency, Research Triangle Park, North Carolina 27711. Designation of this new... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of...

  16. Single and double long pulse laser ablation of aluminum induced in air and water ambient

    NASA Astrophysics Data System (ADS)

    Akbari Jafarabadi, Marzieh; Mahdieh, Mohammad Hossein

    2017-02-01

    In this paper, single pulse and double pulse laser ablation of an aluminum target in two interaction ambient was investigated experimentally. The interaction was performed by nanosecond Nd:YAG laser beam in air and four depths (i.e. 9, 13, 17, and 21 mm) of distilled water ambient. The irradiation was carried out in single and collinear double pulse configurations in both air and liquid ambient. Crater geometry (depth and diameter) was measured by an optical microscope. The results indicated that the crater geometry strongly depends on both single pulse and double pulse configurations and interaction ambient. In single pulse regime, the crater diameter is higher for all water depths compared to that of air. However, the crater depth, depend on water depth, is higher or lower than the crater depth in air. In double pulse laser ablation, there are greater values for both crater diameters and crater depths in the water.

  17. Ambient Air Mitigation Strategies for Reducing Exposures to Mobile Source PM2.5 Emissions

    EPA Science Inventory

    Presentation discussing ambient air mitigation strategies for near-road exposures. The presentation provides an overview of multiple methods, but focuses on the role roadside features (sound walls, vegetation) may play. This presentation summarizes preoviously published work by...

  18. RELATIONSHIP BETWEEN AMBIENT AIR QUALITY AND SELECTED BIRTH DEFECTS, SEVEN COUNTY STUDY, TEXAS, 1997-2000

    EPA Science Inventory

    Background and Objectives: A number of epidemiologic investigations have shown adverse effects of ambient air pollution on reproductive outcomes including spontaneous abortion, fetal growth, preterm delivery, and infant mortality. A southern California, population-based, case-c...

  19. Stirling engine with air working fluid

    DOEpatents

    Corey, John A.

    1985-01-01

    A Stirling engine capable of utilizing air as a working fluid which includes a compact heat exchange module which includes heating tube units, regenerator and cooler positioned about the combustion chamber. This arrangement has the purpose and effect of allowing the construction of an efficient, high-speed, high power-density engine without the use of difficult to seal light gases as working fluids.

  20. Comparison of exposure estimation methods for air pollutants: ambient monitoring data and regional air quality simulation.

    PubMed

    Bravo, Mercedes A; Fuentes, Montserrat; Zhang, Yang; Burr, Michael J; Bell, Michelle L

    2012-07-01

    Air quality modeling could potentially improve exposure estimates for use in epidemiological studies. We investigated this application of air quality modeling by estimating location-specific (point) and spatially-aggregated (county level) exposure concentrations of particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM(2.5)) and ozone (O(3)) for the eastern U.S. in 2002 using the Community Multi-scale Air Quality (CMAQ) modeling system and a traditional approach using ambient monitors. The monitoring approach produced estimates for 370 and 454 counties for PM(2.5) and O(3), respectively. Modeled estimates included 1861 counties, covering 50% more population. The population uncovered by monitors differed from those near monitors (e.g., urbanicity, race, education, age, unemployment, income, modeled pollutant levels). CMAQ overestimated O(3) (annual normalized mean bias=4.30%), while modeled PM(2.5) had an annual normalized mean bias of -2.09%, although bias varied seasonally, from 32% in November to -27% in July. Epidemiology may benefit from air quality modeling, with improved spatial and temporal resolution and the ability to study populations far from monitors that may differ from those near monitors. However, model performance varied by measure of performance, season, and location. Thus, the appropriateness of using such modeled exposures in health studies depends on the pollutant and metric of concern, acceptable level of uncertainty, population of interest, study design, and other factors.

  1. An alternative approach for femtosecond laser induced black silicon in ambient air

    NASA Astrophysics Data System (ADS)

    Ma, Yuncan; Ren, Hai; Si, Jinhai; Sun, Xuehui; Shi, Haitao; Chen, Tao; Chen, Feng; Hou, Xun

    2012-11-01

    An alternative approach for femtosecond laser induced black silicon in ambient air is proposed, in which, black silicon is fabricated on a tellurium coated silicon substrate via femtosecond laser irradiation in ambient air, and selectively etching with hydrofluoric acid is employed to remove the incorporated oxygen. Results of energy dispersive X-ray spectroscopy analysis and absorption measurement show that oxygen is effectively eliminated via etching, and the optical absorption of the black silicon is enhanced.

  2. Ambient air quality and asthma cases in Niğde, Turkey.

    PubMed

    Kara, Ertan; Özdilek, Hasan Göksel; Kara, Emine Erman

    2013-06-01

    Urban air quality is one of the key factors affecting human health. Turkey has transformed itself into an urban society over the last 30 years. At the same time, air pollution has become a serious impairment to health in many urban areas in the country. This is due to many reasons. In this study, a nonparametric evaluation was conducted of health effects that are triggered by urban air pollution. Niğde, the city which is the administrative centre of Nigde province was chosen of the effects of air pollution since, like many central Turkish cities, it is situated on a valley where atmospheric inversion occurs. In this paper, the relationship between ambient urban air quality, namely PM10 and sulphur dioxide (SO2), and human health, specifically asthma, during the winter season is examined. Air pollution data and asthma cases from 2006 to 2010 are covered in this study. The results of our study indicate that total asthma cases reported in Nigde between 2008 and 2010 were highly dependent on ambient SO2 concentration. More asthma cases were recorded when 30 μg m(-3) or higher SO2 was present in the ambient air than those recorded under cleaner ambient air conditions. Moreover, it was determined that in Nigde in 2010, asthma cases reported in males aged between 45 and 64 were closely correlated with ambient SO2 (α=0.05).

  3. Ambient air monitoring for organic compounds, acids, and metals at Los Alamos National Laboratory, January 1991

    SciTech Connect

    Williams, C.H.; Eberhart, C.F.

    1992-10-01

    Los Alamos National Laboratory (LANL) contracted Radian Corporation (Radian) to conduct a short-term, intensive air monitoring program whose goal was to estimate the impact of chemical emissions from LANL on the ambient air environment. A comprehensive emission inventory had identified more than 600 potential air contaminants in LANL`s emissions. A subset of specific target chemicals was selected for monitoring: 20 organic vapors, 6 metals and 5 inorganic acid vapors. These were measured at 5 ground level sampling sites around LANL over seven consecutive days in January 1991. The sampling and analytical strategy used a combination of EPA and NIOSH methods modified for ambient air applications.

  4. Ambient air monitoring for organic compounds, acids, and metals at Los Alamos National Laboratory, January 1991

    SciTech Connect

    Williams, C.H. ); Eberhart, C.F. )

    1992-01-01

    Los Alamos National Laboratory (LANL) contracted Radian Corporation (Radian) to conduct a short-term, intensive air monitoring program whose goal was to estimate the impact of chemical emissions from LANL on the ambient air environment. A comprehensive emission inventory had identified more than 600 potential air contaminants in LANL's emissions. A subset of specific target chemicals was selected for monitoring: 20 organic vapors, 6 metals and 5 inorganic acid vapors. These were measured at 5 ground level sampling sites around LANL over seven consecutive days in January 1991. The sampling and analytical strategy used a combination of EPA and NIOSH methods modified for ambient air applications.

  5. 30 CFR 250.610 - Diesel engine air intakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Diesel engine air intakes. 250.610 Section 250... Well-Workover Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of...

  6. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  7. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  8. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  9. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  10. 30 CFR 250.610 - Diesel engine air intakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Diesel engine air intakes. 250.610 Section 250... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel...

  11. 30 CFR 250.610 - Diesel engine air intakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Diesel engine air intakes. 250.610 Section 250... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel...

  12. 30 CFR 250.610 - Diesel engine air intakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Diesel engine air intakes. 250.610 Section 250... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel...

  13. Inhalation intake of ambient air pollution in California's South Coast Air Basin

    NASA Astrophysics Data System (ADS)

    Marshall, Julian D.; Granvold, Patrick W.; Hoats, Abigail S.; McKone, Thomas E.; Deakin, Elizabeth; W Nazaroff, William

    Reliable estimates of inhalation intake of air pollution and its distribution among a specified population are important for environmental epidemiology, health risk assessment, urban planning, and environmental policy. We computed distributional characteristics of the inhalation intake of five pollutants for a group of ˜25,000 people (˜29,000 person-days) living in California's South Coast Air Basin. Our approach incorporates four main inputs: temporally resolved information about people's location (latitude and longitude), microenvironment, and activity level; temporally and spatially explicit model determinations of ambient concentrations; stochastically determined microenvironmental adjustment factors relating the exposure concentration to the ambient concentration; and, age-, gender-, and activity-specific breathing rates. Our study is restricted to pollutants of outdoor origin, i.e. it does not incorporate intake in a microenvironment from direct emissions into that microenvironment. Median estimated inhalation intake rates (μg d -1) are 53 for benzene, 5.1 for 1,3-butadiene, 8.7×10 -4 for hexavalent chromium in fine particulate matter (Cr-PM 2.5), 30 for diesel fine particulate matter (DPM 2.5), and 68 for ozone. For the four primary pollutants studied, estimated median intake rates are higher for non-whites and for individuals in low-income households than for the population as a whole. For ozone, a secondary pollutant, the reverse is true. Accounting for microenvironmental adjustment factors, population mobility and temporal correlations between pollutant concentrations and breathing rates affects the estimated inhalation intake by 40% on average. The approach presented here could be extended to quantify the impact on intakes and intake distributions of proposed changes in emissions, air quality, and urban infrastructure.

  14. Air breathing engine/rocket trajectory optimization

    NASA Technical Reports Server (NTRS)

    Smith, V. K., III

    1979-01-01

    This research has focused on improving the mathematical models of the air-breathing propulsion systems, which can be mated with the rocket engine model and incorporated in trajectory optimization codes. Improved engine simulations provided accurate representation of the complex cycles proposed for advanced launch vehicles, thereby increasing the confidence in propellant use and payload calculations. The versatile QNEP (Quick Navy Engine Program) was modified to allow treatment of advanced turboaccelerator cycles using hydrogen or hydrocarbon fuels and operating in the vehicle flow field.

  15. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  16. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  17. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  18. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  19. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  20. 40 CFR Appendix E to Part 58 - Probe and Monitoring Path Siting Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... 23. Hughes, E.E. Development of Standard Reference Material for Air Quality Measurement. ISA... Criteria for Ambient Air Quality Monitoring E Appendix E to Part 58 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App....

  1. 40 CFR Appendix E to Part 58 - Probe and Monitoring Path Siting Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Material for Air Quality Measurement. ISA Transactions, 14:281-291, 1975. 24. Altshuller, A.D. and A.G... Criteria for Ambient Air Quality Monitoring E Appendix E to Part 58 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App....

  2. 40 CFR Appendix E to Part 58 - Probe and Monitoring Path Siting Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... 23. Hughes, E.E. Development of Standard Reference Material for Air Quality Measurement. ISA... Criteria for Ambient Air Quality Monitoring E Appendix E to Part 58 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Pt. 58, App....

  3. Optimization of Air-Breathing Engine Concept

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Lavelle, Thomas M.; Hopkins, Dale A.

    1996-01-01

    The design optimization of air-breathing propulsion engine concepts has been accomplished by soft-coupling the NASA Engine Performance Program (NEPP) analyzer with the NASA Lewis multidisciplinary optimization tool COMETBOARDS. Engine problems, with their associated design variables and constraints, were cast as nonlinear optimization problems with thrust as the merit function. Because of the large number of mission points in the flight envelope, the diversity of constraint types, and the overall distortion of the design space; the most reliable optimization algorithm available in COMETBOARDS, when used by itself, could not produce satisfactory, feasible, optimum solutions. However, COMETBOARDS' unique features-which include a cascade strategy, variable and constraint formulations, and scaling devised especially for difficult multidisciplinary applications-successfully optimized the performance of subsonic and supersonic engine concepts. Even when started from different design points, the combined COMETBOARDS and NEPP results converged to the same global optimum solution. This reliable and robust design tool eliminates manual intervention in the design of air-breathing propulsion engines and eases the cycle analysis procedures. It is also much easier to use than other codes, which is an added benefit. This paper describes COMETBOARDS and its cascade strategy and illustrates the capabilities of the combined design tool through the optimization of a high-bypass- turbofan wave-rotor-topped subsonic engine and a mixed-flow-turbofan supersonic engine.

  4. Air-breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Quick Time movie depicts the Rocketdyne static test of an air-breathing rocket. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's advanced Transportation Program at the Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  5. Modelling of operation of a lithium-air battery with ambient air and oxygen-selective membrane

    NASA Astrophysics Data System (ADS)

    Sahapatsombut, Ukrit; Cheng, Hua; Scott, Keith

    2014-03-01

    A macro-homogeneous model has been developed to evaluate the impact of replacing pure oxygen with ambient air on the performance of a rechargeable non-aqueous Li-air battery. The model exhibits a significant reduction in discharge capacity, e.g. from 1240 to 226 mAh gcarbon-1 at 0.05 mA cm-2 when using ambient air rather than pure oxygen. The model correlates the relationship between the performance and electrolyte decomposition and formation of discharge products (such as Li2O2 and Li2CO3) under ambient air conditions. The model predicts a great benefit of using an oxygen-selective membrane on increasing capacity. The results indicate a good agreement between the experimental data and the model.

  6. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  7. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  8. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  9. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  10. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  11. Effect of Ambient Design Temperature on Air-Cooled Binary Plant Output

    SciTech Connect

    Dan Wendt; Greg Mines

    2011-10-01

    Air-cooled binary plants are designed to provide a specified level of power production at a particular air temperature. Nominally this air temperature is the annual mean or average air temperature for the plant location. This study investigates the effect that changing the design air temperature has on power generation for an air-cooled binary plant producing power from a resource with a declining production fluid temperature and fluctuating ambient temperatures. This analysis was performed for plants operating both with and without a geothermal fluid outlet temperature limit. Aspen Plus process simulation software was used to develop optimal air-cooled binary plant designs for specific ambient temperatures as well as to rate the performance of the plant designs at off-design operating conditions. Results include calculation of annual and plant lifetime power generation as well as evaluation of plant operating characteristics, such as improved power generation capabilities during summer months when electric power prices are at peak levels.

  12. Air-Breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  13. Comparison of stationary and personal air sampling with an air dispersion model for children's ambient exposure to manganese.

    PubMed

    Fulk, Florence; Haynes, Erin N; Hilbert, Timothy J; Brown, David; Petersen, Dan; Reponen, Tiina

    2016-09-01

    Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to assess exposure for children enrolled in the Communities Actively Researching Exposure Study in Marietta, OH. Ambient air Mn concentration values were modeled using US Environmental Protection Agency's Air Dispersion Model AERMOD based on emissions from the ferromanganese refinery located in Marietta. Modeled Mn concentrations were compared with Mn concentrations from a nearby stationary air monitor. The Index of Agreement for modeled versus monitored data was 0.34 (48 h levels) and 0.79 (monthly levels). Fractional bias was 0.026 for 48 h levels and -0.019 for monthly levels. The ratio of modeled ambient air Mn to measured ambient air Mn at the annual time scale was 0.94. Modeled values were also time matched to personal air samples for 19 children. The modeled values explained a greater degree of variability in personal exposures compared with time-weighted distance from the emission source. Based on these results modeled Mn concentrations provided a suitable approach for assessing airborne Mn exposure in this cohort.

  14. Air turbo-ramjet engine

    NASA Technical Reports Server (NTRS)

    Kepler, Charles E. (Inventor)

    1991-01-01

    A jet engine designed to power a supersonic airplane throughout a range of speeds from subsonic to high supersonic includes a housing which bounds an internal passage having in succession a fixed-area inlet section, a diverging passage section, a mixing section, a combustion section, and an outlet section. A fan rotor rotates in the inlet section and includes a plurality of rotor blade members. The housing includes a main body and at least one flap which is movable between one end position in which it externally bounds a portion of the diverging passage section and another end position in which it externally delimits a diverging discharge passage connecting the diverging passage section with the exterior of the housing. The cross-sectional area of the outlet section is adjustable. The rotor is driven in rotation by a fuel/oxygen powered turbine the outlet of which communicates with the mixing section, but the driving action of the turbine is discontinued at actual supersonic velocities exceeding a predetermined supersonic velocity. The pitch of at least one element of each of the rotor blade members is adjustable.

  15. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... arsenic. 61.184 Section 61.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to...

  16. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... arsenic. 61.184 Section 61.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to...

  17. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... arsenic. 61.184 Section 61.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to...

  18. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... arsenic. 61.184 Section 61.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to...

  19. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... arsenic. 61.184 Section 61.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to...

  20. EFFECTS OF METAL COMPONENTS IN CONCENTRATED AMBIENT AIR PARTICLES ON PULMONARY INJURY

    EPA Science Inventory

    EFFECTS OF METAL COMPONENTS IN CONCENTRATED AMBIENT AIR PARTICLES ON PULMONARY INJURY. Yuh-Chin Huang, Jackie Stonehuerner, Jackie Carter, Andrew J. Ghio, Robert B. Devlin. NHEERL, US EPA, RTP, NC.
    The mechanisms for cardiopulmonary morbidity associated with exposure to air po...

  1. Waste combustion as a source of ambient air polybrominated diphenylesters (PBDEs)

    EPA Science Inventory

    The first comprehensive set of U.S. data on PBDE concentrations from waste combustion, with more than 40 BDE congeners reported, was compared to ambient air levels of bromodiphenylethers in the U.S. Concentrations of PBDEs were determined in the raw, pre-air pollution control sys...

  2. 75 FR 35519 - Primary National Ambient Air Quality Standard for Sulfur Dioxide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-22

    ...Based on its review of the air quality criteria for oxides of sulfur and the primary national ambient air quality standard (NAAQS) for oxides of sulfur as measured by sulfur dioxide (SO2), EPA is revising the primary SO2 NAAQS to provide requisite protection of public health with an adequate margin of safety. Specifically, EPA is establishing a new 1-hour SO2......

  3. Environmental Technology Verification Report for Applikon MARGA Semi-Continuous Ambient Air Monitoring System

    EPA Science Inventory

    The verification test was conducted oer a period of 30 days (October 1 to October 31, 2008) and involved the continuous operation of duplicate semi-continuous monitoring technologies at the Burdens Creek Air Monitoring Site, an existing ambient-air monitoring station located near...

  4. HYDROCARBON AND CARBONYL OZONE PRECURSORS IN MEXICO CITY AMBIENT AIR

    EPA Science Inventory

    Urban air pollution is an environmental problem in many cities around the world that has serious immediate and long-term implications to the health of the population and to the physical environment. Mexico City, in particular, faces a severe air pollution problem. The city is...

  5. Study of the formation of 3-D titania nanofibrous structure by MHz femtosecond laser in ambient air

    SciTech Connect

    Tavangar, Amirhossein; Venkatakrishnan, K.; Tan Bo

    2013-01-14

    In this study, we describe the formation mechanism of web-like three-dimensional (3-D) titania nanofibrous structures during femtosecond laser ablation of titanium (Ti) targets in the presence of background air. First, we demonstrate the mechanism of ablation of Ti targets by multiple femtosecond laser pulses at ambient air in an explicit analytical form. The formulas for evaporation rates and the number of ablated particles, which is analogous to the deposition rate of the synthesized nanofibers, for the ablation by a single pulse and multiple pulses as a function of laser parameters, background gas, and material properties are predicted and compared to experimental results. Afterwards, the formation of nanofibrous structures is demonstrated by applying an existing simplified kinetic model to Ti targets and ambient conditions. The predicted theory provides nanofiber diameter dependency with the combination of laser parameters, target properties, and ambient gas characteristics. Experimental studies are then performed on titania nanofibrous structures synthesized by laser ablation of Ti targets using MHz repletion-rate femtosecond laser at ambient air. The models' predictions are then compared with the experimental results, where nanostructures with different morphologies are manufactured by altering laser parameters. Our results indicate that femtosecond laser ablation of Ti targets at air background yields crystalline titania nanostructures. The formation of crystalline titania nanostructures is preceded by thermal mechanism of nucleation and growth. The results point out that laser pulse repetition and dwell time can control the density, size, and pore size of the engineered nanofibrous structure. As the deposition rate of nanostructures is analogous to the ablation rate of the target, higher density of nanofibrous structure is seen at greater laser fluences. The predicted theory can be applied to predict ablation mechanism and nanofiber formation of different

  6. Ambient air quality monitoring during the H1N1 influence period in Pune (India).

    PubMed

    Pathak, M; Deshpande, A; Mirashe, P K; Sorte, R B; Ojha, A

    2010-10-01

    Ambient air quality in an urban area is directly linked with activity level in the city including transport, business and industrial activities. Maharashtra Pollution Control Board (MPCB) has established an ambient air quality network in the city including state-of-the-art continuous air quality monitoring stations which indicate short duration air quality variations for criteria and non-criteria pollutants. The influence of H1N1 outbreak in Pune hitting its worst pandemic condition, led the civic authorities to implement stringent isolation measures including closure of schools, colleges, business malls, cinema halls, etc. Additionally, the fear of such a pandemic brought the city to a stand still. It was therefore necessary to assess the impacts of such activity level on ambient air quality in the city. It has been observed that such events have positive impacts on air quality of the city. There was a decrease in PM concentration almost to the tune of 30 to 40% if the impacts of precipitation, i.e. seasonal variations, are taken into account. Similarly, the non criteria pollutants too showed a marked but unusual decrease in their concentrations in this ever growing city. The influence of these in turn led to lowered concentrations of secondary pollutants, i.e. O3. Overall, the ambient air quality of Pune was found to be improved during the study period.

  7. Benzene levels in ambient air and breath of smokers and nonsmokers in urban and pristine environments

    SciTech Connect

    Wester, R.C.; Maibach, H.I.; Gruenke, L.D.; Craig, J.C.

    1986-01-01

    Benzene levels in human breath and in ambient air were compared in the urban area of San Francisco (SF) and in a more remote coastal pristine setting of Stinson Beach, Calif. (SB). Benzene analysis was done by gas chromatography-mass spectroscopy (GC-MS). Ambient benzene levels were sevenfold higher in SF (2.6 +/- 1.3 ppb, n = 25) than SB (0.38 +/- 0.39 ppb, n = 21). In SF, benzene in smokers' breath (6.8 +/- 3.0 ppb) was greater than in nonsmokers' breath (2.5 +/- 0.8 ppb) and smokers' ambient air (3.3 +/- 0.8 ppb). In SB the same pattern was observed: benzene in smokers' breath was higher than in nonsmokers' breath and ambient air. Benzene in SF nonsmokers' breath was greater than in SB nonsmokers' breath. Marijuana-only smokers had benzene breath levels between those of smokers and nonsmokers. There was little correlation between benzene in breath and number of cigarettes smoked, or with other benzene exposures such as diet. Of special interest was the finding that benzene in breath of SF nonsmokers (2.5 +/- 0.8 ppb) was greater than that in nonsmokers ambient air (1.4 +/- 0.1 ppb). The same was true in SB, where benzene in nonsmokers breath was greater than ambient air (1.8 +/- 0.2 ppb versus 1.0 +/- 0.1 ppb on d 1 and 1.3 +/- 0.3 ppb versus 0.23 +/- 0.18 ppb on d 2). This suggests an additional source of benzene other than outdoor ambient air.

  8. Ambient air temperature effects on the temperature of sewage sludge composting process.

    PubMed

    Huang, Qi-fei; Chen, Tong-bin; Gao, Ding; Huang, Ze-chun

    2005-01-01

    Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1: 0: 1 and 3: 1: 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5 degrees C when ambient air temperature changed 13 degrees C. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3 degrees C when ambient air temperature changed 8-15 degrees C. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent (at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate (at a volume ratio of 3:1:2), the hysteresis time was long and ranging 1.9-3.1 h.

  9. Ambient and household air pollution: complex triggers of disease

    PubMed Central

    Farmer, Stephen A.; Nelin, Timothy D.; Falvo, Michael J.

    2014-01-01

    Concentrations of outdoor air pollution are on the rise, particularly due to rapid urbanization worldwide. Alternatively, poor ventilation, cigarette smoke, and other toxic chemicals contribute to rising concentrations of indoor air pollution. The World Health Organization recently reported that deaths attributable to indoor and outdoor air pollutant exposure are more than double what was originally documented. Epidemiological, clinical, and animal data have demonstrated a clear connection between rising concentrations of air pollution (both indoor and outdoor) and a host of adverse health effects. During the past five years, animal, clinical, and epidemiological studies have explored the adverse health effects associated with exposure to both indoor and outdoor air pollutants throughout the various stages of life. This review provides a summary of the detrimental effects of air pollution through examination of current animal, clinical, and epidemiological studies and exposure during three different periods: maternal (in utero), early life, and adulthood. Additionally, we recommend future lines of research while suggesting conceivable strategies to curb exposure to indoor and outdoor air pollutants. PMID:24929855

  10. Ambient and household air pollution: complex triggers of disease.

    PubMed

    Farmer, Stephen A; Nelin, Timothy D; Falvo, Michael J; Wold, Loren E

    2014-08-15

    Concentrations of outdoor air pollution are on the rise, particularly due to rapid urbanization worldwide. Alternatively, poor ventilation, cigarette smoke, and other toxic chemicals contribute to rising concentrations of indoor air pollution. The World Health Organization recently reported that deaths attributable to indoor and outdoor air pollutant exposure are more than double what was originally documented. Epidemiological, clinical, and animal data have demonstrated a clear connection between rising concentrations of air pollution (both indoor and outdoor) and a host of adverse health effects. During the past five years, animal, clinical, and epidemiological studies have explored the adverse health effects associated with exposure to both indoor and outdoor air pollutants throughout the various stages of life. This review provides a summary of the detrimental effects of air pollution through examination of current animal, clinical, and epidemiological studies and exposure during three different periods: maternal (in utero), early life, and adulthood. Additionally, we recommend future lines of research while suggesting conceivable strategies to curb exposure to indoor and outdoor air pollutants.

  11. 40 CFR 1065.125 - Engine intake air.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  12. 40 CFR 1065.125 - Engine intake air.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  13. 40 CFR 1065.125 - Engine intake air.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  14. 40 CFR 1065.125 - Engine intake air.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  15. 40 CFR 1065.125 - Engine intake air.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  16. 14 CFR 23.1111 - Turbine engine bleed air system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Turbine engine bleed air system. 23.1111 Section 23.1111 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Induction System § 23.1111 Turbine engine bleed air system. For turbine engine bleed air systems,...

  17. 14 CFR 23.1111 - Turbine engine bleed air system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine bleed air system. 23.1111 Section 23.1111 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Induction System § 23.1111 Turbine engine bleed air system. For turbine engine bleed air systems,...

  18. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. S Appendix S to Part 50—Interpretation of the Primary... be submitted to EPA's Air Quality System (AQS), or otherwise available to EPA, meeting...

  19. Automatic electrochemical ambient air monitor for chloride and chlorine

    DOEpatents

    Mueller, Theodore R.

    1976-07-13

    An electrochemical monitoring system has been provided for determining chloride and chlorine in air at levels of from about 10-1000 parts per billion. The chloride is determined by oxidation to chlorine followed by reduction to chloride in a closed system. Chlorine is determined by direct reduction at a platinum electrode in 6 M H.sub.2 SO.sub.4 electrolyte. A fully automated system is utilized to (1) acquire and store a value corresponding to electrolyte-containing impurities, (2) subtract this value from that obtained in the presence of air, (3) generate coulometrically a standard sample of chlorine mixed with air sample, and determine it as chlorine and/or chloride, and (4) calculate, display, and store for permanent record the ratio of the signal obtained from the air sample and that obtained with the standard.

  20. A lightweight ambient air-cooling unit for use in hazardous environments.

    PubMed

    Chen, Y T; Constable, S H; Bomalaski, S H

    1997-01-01

    Recent research demonstrated (a) the effectiveness of intermittent conditioned air cooling during rest breaks to significantly reduce cumulative heat storage and (b) that longer work sessions were possible for individuals wearing chemical defense ensembles. To further advance this concept, a strategy for implementing continuous air cooling was conceived; ambient air cooling was added during work cycles and conditioned air cooling was delivered during rest periods. A compact battery-powered beltpack cooling unit (3.9 kg) designed and made at the U.S. Air Force Armstrong Laboratory was used to deliver 5.7 L/sec filtered ambient air during work cycles: 4.7 L/sec to the body and 1 L/sec to the face. Five experimental cycles were conducted in a thermally controlled chamber under warm conditions (32 degrees C, 40% relative humidity) with (1) no cooling-intermittent work, (2) intermittent cooling, (3) continuous cooling during intermittent exercise, and (4) no cooling-continuous work and (5) ambient air cooling during continuous exercise. Intermittent, conditioned, and continuous air cooling resulted in significant reductions in rectal temperature, mean skin temperature, and heart rate as compared with the no-cooling trials. The continuous air-cooling trial significantly improved thermal comfort and sweat evaporation. Results suggest that ambient air delivered during work cycles by a lightweight portable unit (in conjunction with conditioned air delivered during rest periods), can definitely improve personal comfort, reduce skin temperature, and decrease the cumulative fatigue common to repeated work/rest cycles in selected military and industrial applications in which individuals work in chemical defense ensembles.

  1. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... location must be within 10 cm of the engine intake system (i.e., the air cleaner, for most engines.) (b... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19...

  2. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are...

  3. Assessment of ambient air quality in Eskişehir, Turkey.

    PubMed

    Ozden, O; Döğeroğlu, T; Kara, S

    2008-07-01

    This paper presents an assessment of air quality of the city Eskişehir, located 230 km southwest to the capital of Turkey. Only five of the major air pollutants, most studied worldwide and available for the region, were considered for the assessment. Available sulphur dioxide (SO(2)), particulate matter (PM), nitrogen dioxide (NO(2)), ozone (O(3)), and non-methane volatile organic carbons (NMVOCs) data from local emission inventory studies provided relative source contributions of the selected pollutants to the region. The contributions of these typical pollution parameters, selected for characterizing such an urban atmosphere, were compared with the data established for other cities in the nation and world countries. Additionally, regional ambient SO(2) and PM concentrations, determined by semi-automatic monitoring at two sites, were gathered from the National Ambient Air Monitoring Network (NAAMN). Regional data for ambient NO(2) (as a precursor of ozone as VOCs) and ozone concentrations, through the application of the passive sampling method, were provided by the still ongoing local air quality monitoring studies conducted at six different sites, as representatives of either the traffic-dense-, or coal/natural gas burning residential-, or industrial/rural-localities of the city. Passively sampled ozone data at a single rural site were also verified with the data from a continuous automatic ozone monitoring system located at that site. Effects of variations in seasonal-activities, newly established railway system, and switching to natural gas usage on the temporal changes of air quality were all considered for the assessment. Based on the comparisons with the national [AQCR (Air Quality Control Regulation). Ministry of Environment (MOE), Ankara. Official Newspaper 19269; 1986.] and a number of international [WHO (World Health Organization). Guidelines for Air Quality. Geneva; 2000. Downloaded in January 2006, website: http://www.who.int/peh/; EU (European Union

  4. Optimization of non-aqueous electrolytes for Primary lithium/air batteries operated in Ambient Enviroment

    SciTech Connect

    Xu, Wu; Xiao, Jie; Zhang, Jian; Wang, Deyu; Zhang, Jiguang

    2009-07-07

    The selection and optimization of non-aqueous electrolytes for ambient operations of lithium/air batteries has been studied. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between lithium anode and water during discharge process. It is critical to make the electrolytes with high polarity so that it can reduce wetting and flooding of carbon based air electrode and lead to improved battery performance. For ambient operations, the viscosity, ionic conductivity, and oxygen solubility of the electrolyte are less important than the polarity of organic solvents once the electrolyte has reasonable viscosity, conductivity, and oxygen solubility. It has been found that PC/EC mixture is the best solvent system and LiTFSI is the most feasible salt for ambient operations of Li/air batteries. Battery performance is not very sensitive to PC/EC ratio or salt concentration.

  5. Gene by environment interaction and ambient air pollution.

    PubMed

    Romieu, Isabelle; Moreno-Macias, Hortensia; London, Stephanie J

    2010-05-01

    Epidemiologic studies have clearly shown that air pollution is associated with a range of respiratory effects. Recent research has identified oxidative stress as a major biologic pathway underlying the toxic effect of air pollutants. Genetic susceptibility is likely to play a role in response to air pollution. Genes involved in oxidative stress and inflammatory pathways are logical candidates for the study of the interaction with air pollutants. In this article we use the example of asthma, a genetically complex disease, to address the issue of gene by environment interaction with air pollution. The majority of studies have focused on the genes GSTM1, GSTP1, NQO1, and TNF, but the inconsistency of the results prevents the drawing of firm conclusions. The limited sample size of most studies to date make them underpowered for the study of gene by gene interactions. Large consortia of studies with repeated measurements of environmental exposures and clear phenotypic assessments may help determine special environmental triggers and the window of susceptibility in the development of atopy and asthma. The role of gene by gene interactions and epigenetic mechanisms needs to be considered along with gene by environment interactions.

  6. Biogenic hydrocarbon contribution to the ambient air of selected areas

    NASA Astrophysics Data System (ADS)

    Arnts, Robert R.; Meeks, Sarah A.

    In response to suggestions that biogenic emissions are responsible for high hydrocarbon concentrations described in several reports, a short-term sampling program was initiated in the reported areas to test this hypothesis. Limited numbers of whole-air samples were collected in Tedlar bags and analyzed by gas chromatography (GC) with flame ionization detection. Tulsa air was found to contain an average of 0.2% isoprene of the total nonmethane hydrocarbon (TNMHC) load. Rio Blanco County, Colorado, and Smoky Mountain air, respectively, averaged about 2 % and 4 % biogenic hydrocarbon of the total nonmethane hydrocarbon loads. Isoprene appears to be a dominant olefin in rural and remote areas. Although the tests were of short duration, results suggest monoterpenes and isoprene constitute only minor components in these areas relative to anthropogenic hydrocarbons.

  7. Measurements of lower carbonyls in Rome ambient air

    NASA Astrophysics Data System (ADS)

    Possanzini, M.; Di Palo, V.; Petricca, M.; Fratarcangeli, R.; Brocco, D.

    Ambient levels and diurnal profiles of lower carbonyls were measured in Rome during selected days of summer 1994 and winter 1995. The most abundant carbonyls were formaldehyde (up to 27 ppb) followed by ethanal (< 17 ppb) and acetone (< 9 ppb). Gas-phase concentrations of other seven carbonyls were in the 0-3 ppb range. The results were discussed with respect to direct emissions and photochemical production. Using carbonyl/CO concentration ratios mobil source emissions of carbonyls were estimated for the urban area. The secondary production of C 1-C 3 aldehydes from reactions of alkenes with O 3 and OH radicals during the early morning hours of summer days was also calculated. The daytime pattern of carbonyls was found to be similar to that of toluene in wintertime and close to that of ozone in summer periods conductive to photochemical pollution episodes.

  8. Assessing plant response to ambient ozone: growth of young apple trees in open-top chambers and corresponding ambient air plots.

    PubMed

    Manning, W J; Cooley, D R; Tuttle, A F; Frenkel, M A; Bergweiler, C J

    2004-12-01

    Open-top chambers (OTCs) and corresponding ambient air plots (AA) were used to assess the impact of ambient ozone on growth of newly planted apple trees at the Montague Field research center in Amherst, MA. Two-year-old apple trees (Malus domestica Borkh 'Rogers Red McIntosh') were planted in the ground in circular plots. Four of the plots were enclosed with OTCs where incoming air was charcoal-filtered (CF); four were enclosed with OTCs where incoming air was not charcoal-filtered (NF) and four were not enclosed, allowing access to ambient air conditions (AA). Conditions in both CF and NF OTCs resulted in increased tree growth and changed incidence of disease and arthropod pests, compared to trees in AA. As a result, we were not able to use the OTC method to assess the impact of ambient ozone on growth of young apple trees in Amherst, MA.

  9. Comparison of stationary and personal air sampling with an air dispersion model for children’s ambient exposure to manganese

    EPA Science Inventory

    Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to asse...

  10. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  11. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  12. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  13. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  14. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  15. Direct Capture of CO2 from Ambient Air.

    PubMed

    Sanz-Pérez, Eloy S; Murdock, Christopher R; Didas, Stephanie A; Jones, Christopher W

    2016-10-12

    The increase in the global atmospheric CO2 concentration resulting from over a century of combustion of fossil fuels has been associated with significant global climate change. With the global population increase driving continued increases in fossil fuel use, humanity's primary reliance on fossil energy for the next several decades is assured. Traditional modes of carbon capture such as precombustion and postcombustion CO2 capture from large point sources can help slow the rate of increase of the atmospheric CO2 concentration, but only the direct removal of CO2 from the air, or "direct air capture" (DAC), can actually reduce the global atmospheric CO2 concentration. The past decade has seen a steep rise in the use of chemical sorbents that are cycled through sorption and desorption cycles for CO2 removal from ultradilute gases such as air. This Review provides a historical overview of the field of DAC, along with an exhaustive description of the use of chemical sorbents targeted at this application. Solvents and solid sorbents that interact strongly with CO2 are described, including basic solvents, supported amine and ammonium materials, and metal-organic frameworks (MOFs), as the primary classes of chemical sorbents. Hypothetical processes for the deployment of such sorbents are discussed, as well as the limited array of technoeconomic analyses published on DAC. Overall, it is concluded that there are many new materials that could play a role in emerging DAC technologies. However, these materials need to be further investigated and developed with a practical sorbent-air contacting process in mind if society is to make rapid progress in deploying DAC as a means of mitigating climate change.

  16. Differences in creep performance of a HIPed silicon nitride in ambient air and inert environments

    SciTech Connect

    Wereszczak, A.A.; Kirkland, T.P.; Ferber, M.K.

    1995-04-01

    High temperature tensile creep studies of a commercially available hot isostatically pressed (HIPed) silicon nitride were conducted in ambient air and argon environments. The creep performance of this HIPed silicon nitride was found to be different in these environments. The material crept faster (and had a consequential shorter lifetime) in argon than in ambient air at 1370{degrees}C at tensile stresses between 110-140 MPa. The stress dependence of the minimum creep rate was found to be {approx} 6 in argon and {approx} 3.5 in air, while the minimum creep rates were almost an order of magnitude faster in argon than in air at equivalent tensile stresses. Differences in the creep performance are explained with reference to the presence or absence of oxygen in the two environments.

  17. 40 CFR Appendix R to Part 50 - Interpretation of the National Ambient Air Quality Standards for Lead

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt... data shall be processed at face value; that is, without any transformation or scaling. Data...

  18. 40 CFR Appendix R to Part 50 - Interpretation of the National Ambient Air Quality Standards for Lead

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt... data shall be processed at face value; that is, without any transformation or scaling. Data...

  19. 40 CFR Appendix R to Part 50 - Interpretation of the National Ambient Air Quality Standards for Lead

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt... data shall be processed at face value; that is, without any transformation or scaling. Data...

  20. Request For Further Clarification on EPA's Definition of Ambient Air

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  1. Ambient Air for Offshore Liquified Natural Gas Broadwater Project

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  2. Application of amine-tethered solid sorbents for direct CO2 capture from the ambient air.

    PubMed

    Choi, Sunho; Drese, Jeffrey H; Eisenberger, Peter M; Jones, Christopher W

    2011-03-15

    While current carbon capture and sequestration (CCS) technologies for large point sources can help address the impact of CO(2) buildup on global climate change, these technologies can at best slow the rate of increase of the atmospheric CO(2) concentration. In contrast, the direct CO(2) capture from ambient air offers the potential to be a truly carbon negative technology. We propose here that amine-based solid adsorbents have significant promise as key components of a hypothetical air capture process. Specifically, the CO(2) capture characteristics of hyperbranched aminosilica (HAS) materials are evaluated here using CO(2) mixtures that simulate ambient atmospheric concentrations (400 ppm CO(2) = "air capture") as well as more traditional conditions simulating flue gas (10% CO(2)). The air capture experiments demonstrate that the adsorption capacity of HAS adsorbents are only marginally influenced even with a significant dilution of the CO(2) concentration by a factor of 250, while capturing CO(2) reversibly without significant degradation of performance in multicyclic operation. These results suggest that solid amine-based air capture processes have the potential to be an effective approach to extracting CO(2) from the ambient air.

  3. A review of the impact of fireworks on particulate matter in ambient air.

    PubMed

    Lin, Chi-Chi

    2016-12-01

    To determine the impact of fireworks (FW) and firecrackers (FC) on particulate matter (PM) in ambient air, we reviewed evidence related to ambient PM during FW/FC periods; specifically, PM concentration, size, morphology, chemical components, including water-soluble ions and trace metals, and associated human health risks caused by exposure to FW/FC PM were reviewed. A large body of research suggests that outdoor ambient PM levels increase significantly during FW/FC displays. Furthermore, FW/FC PM remains suspended in the air, contributing to high PM concentrations for a long period. Increased PM from burning FW and FC mainly comprises fine and ultrafine spherical particles. Elevated levels of various trace metals, ions, elemental carbon (EC), organic carbon (OC), and organics in PM are present during FW/FC periods.

  4. 75 FR 71033 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Agency FR Federal Register FRM Federal Reference Method IQ Intelligence Quotient NAAQS National Ambient... include IQ loss, poor academic achievement, long- term learning disabilities, and an increased risk...

  5. Performance of the Proposed New Federal Reference Methods for Measuring Ozone Concentrations in Ambient Air

    EPA Science Inventory

    The current Federal Reference Method (FRM) for measuring concentrations of ozone in ambient air, described in EPA regulations at 40 CFR Part 50, Appendix D, is based on the dry, gas-phase, chemiluminescence reaction between ethylene (C2H4) and any ozone (O

  6. AMBIENT AIR QUALITY AND SELECTED BIRTH DEFECTS, SEVEN COUNTY STUDY, TEXAS, 1997-2000

    EPA Science Inventory

    Background: A number of epidemiologic investigations have shown adverse effects of ambient air pollution on reproductive outcomes. A recent case-control study found associations between

    second gestational month carbon monoxide and ozone exposure and elevated risks of selec...

  7. Evaluation and Comparison of Chemiluminescence and UV Photometric Methods for Measuring Ozone Concentrations in Ambient Air

    EPA Science Inventory

    The current Federal Reference Method (FRM) for measuring concentrations of ozone in ambient air is based on the dry, gas-phase, chemiluminescence reaction between ethylene (C2H4) and any ozone (O3) that may be p...

  8. 40 CFR Appendix D to Part 58 - Network Design Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...—Network Design Criteria for Ambient Air Quality Monitoring 1. Monitoring Objectives and Spatial Scales 2.... References 1. Monitoring Objectives and Spatial Scales The purpose of this appendix is to describe monitoring... and path placement, are described in appendix E to this part. 1.2Spatial Scales. (a) To clarify...

  9. 40 CFR Appendix D to Part 58 - Network Design Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...—Network Design Criteria for Ambient Air Quality Monitoring 1. Monitoring Objectives and Spatial Scales 2.... References 1. Monitoring Objectives and Spatial Scales The purpose of this appendix is to describe monitoring... and path placement, are described in appendix E to this part. 1.2Spatial Scales. (a) To clarify...

  10. 40 CFR Appendix D to Part 58 - Network Design Criteria for Ambient Air Quality Monitoring

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...—Network Design Criteria for Ambient Air Quality Monitoring 1. Monitoring Objectives and Spatial Scales 2.... References 1. Monitoring Objectives and Spatial Scales The purpose of this appendix is to describe monitoring... and path placement, are described in appendix E to this part. 1.2Spatial Scales. (a) To clarify...

  11. 76 FR 15974 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-22

    ... particulate matter (TSP) (High-Volume Method, 40 CFR Part 50, Appendix B), with a particular extraction and... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of Four New Equivalent Methods AGENCY: Environmental Protection Agency. ACTION: Notice of...

  12. Comparison of the measurement techniques employed for evaluation of ambient air odor quality

    NASA Astrophysics Data System (ADS)

    Wojnowski, Wojciech; Majchrzak, Tomasz; Gebicki, Jacek; Dymerski, Tomasz; Namieśnik, Jacek

    2016-11-01

    The paper presents the results of investigation on ambient air odor quality in a vicinity of the industrial sewage treatment plant being a part of the crude oil processing plant. The investigation was performed during spring-winter season using a prototype of electronic nose and the Nasal Ranger field olfactometers. The prototype was equipped with a set of six semiconductor sensors by FIGARO Co. and one PID-type sensor. The field olfactometers were used to determine mean concentration of odorants, which amounted from 2.2 to 20.2 ou/m3 depending on the place of measurement. In case of the investigation with the electronic nose prototype a classification of the ambient air samples with respect to the place of sampling was performed utilizing the kNN (where k=3) algorithm supported with a cross-validation method. Correct classification of the ambient air samples was at the level of 47.9%. Performed investigation revealed that evaluation of the ambient air samples with respect to odor was possible using the electronic nose instrument.

  13. CONCENTRATED AMBIENT AIR PARTICLES INDUCE PULMONARY INFLAMMATION IN HEALTHY HUMAN VOLUNTEERS

    EPA Science Inventory


    We tested the hypothesis that exposure of healthy volunteers to concentrated ambient particles (CAPS) is associated with an influx of inflammatory cells into the lower respiratory tract. Thirty-eight volunteers were exposed to either filtered air or particles concentrated fro...

  14. Report on sampling and analysis of ambient air at the central waste complex

    SciTech Connect

    Stauffer, M., Fluor Daniel Hanford

    1997-02-13

    Over 160 ambient indoor air samples were collected from warehouses at the Central Waste Complex used for the storage of low- level radioactive and mixed wastes. These grab (SUMMA) samples were analyzed by gas chromatography-mass spectrometry using a modified EPA TO-14 procedure. The data from this survey suggest that several buildings had elevated concentrations of volatile organic compounds.

  15. Case report: Atrial fibrillation following exposure to ambient air pollution particles

    EPA Science Inventory

    CONTEXT: Exposure to air pollution can result in the onset of atrial fibrillation. CASE PRESENTATION: We present a case of a 58 year old woman who volunteered to participate in a controlled exposure to concentrated ambient particles (CAPs). Twenty minutes into the exposure, there...

  16. COMPARISON OF FAST GC/TOFMS WITH METHOD TO-14 FOR ANALYSIS OF AMBIENT AIR SAMPLES

    EPA Science Inventory

    Field studies using portable gas chromatographs (PGC) to analyze volatile organic compounds in ambient air usually include, as reference standard method, the analysis of concurrent, collocated canister samples by EPA Method TO-14. Each laboratory analysis takes about an hour a...

  17. Test/QA Plan for Verification of Semi-Continuous Ambient Air Monitoring Systems - Second Round

    EPA Science Inventory

    Test/QA Plan for Verification of Semi-Continuous Ambient Air Monitoring Systems - Second Round. Changes reflect performance of second round of testing at new location and with various changes to personnel. Additional changes reflect general improvements to the Version 1 test/QA...

  18. 78 FR 52893 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-27

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 50, 51, 70 and 71 RIN 2060-AR34 Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements Correction In proposed rule...

  19. A STRINGENT COMPARISON OF SAMPLING AND ANALYSIS METHODS FOR VOCS IN AMBIENT AIR

    EPA Science Inventory

    A carefully designed study was conducted during the summer of 1998 to simultaneously collect samples of ambient air by canisters and compare the analysis results to direct sorbent preconcentration results taken at the time of sample collection. A total of 32 1-h sample sets we...

  20. OZONE AMBIENT AIR QUALITY STANDARD HAS BENEFICIAL EFFECT ON PONDEROSA PINE IN CALIFORNIA

    EPA Science Inventory

    Ambient air quality standards and control strategies are implemented to protect humans and vegetation from adverse effects. However, to date there has not been a simple and objective method to determine if the standards and resultant control strategies have reduced O3 impacts on ...

  1. Estimates of the national benefits and costs of improving ambient air quality

    SciTech Connect

    Brady, G.L.; Bower, B.T.; Lakhani, H.A.

    1983-04-01

    This paper examines the estimates of national benefits and national costs of ambient air quality improvement in the US for the period 1970 to 1978. Analysis must be at the micro-level for both receptors of pollution and the dischargers of residuals. Section 2 discusses techniques for estimating the national benefits from improving ambient air quality. The literature on national benefits to health (mortality and morbidity) and non-health (avoiding damages to materials, plants, crops, etc.) is critically reviewed in this section. For the period 1970 to 1978, the value of these benefits ranged from about $5 billion to $51 billion, with a point estimate of about $22 billion. The national cost estimates by the Council on Environmental Quality, Bureau of Economic Analysis, and McGraw-Hill are provided in section 2. Cost estimates must include not only the end-of-pipe treatment measures, but also the alternatives: changes in product specification, product mix, processes, etc. These types of responses are not generally considered in estimates of national costs of improving ambient air quality ranged from $8 to $9 billion in 1978 dollars. Section 4 concludes that the national benefits for improving ambient air quality exceed the national costs for the average and the high values of benefits, but not for the low estimates.

  2. Estimates of the national benefits and costs of improving ambient air quality

    SciTech Connect

    Brady, G.L.; Bower, B.T.; Lakhani, H.A.

    1983-04-01

    This paper examines the estimates of national benefits and national costs of ambient air quality improvement in the United States for the period 1970 to 1978. Analysis must be at the micro-level for both receptors of pollution and the dischargers of residuals. Section 2 discusses techniques for estimating the national benefits from improving ambient air quality. The literature on national benefits to health (mortality and morbidity) and non-health (avoiding damages to materials, plants, crops, etc.) is critically reviewed in this section. For the period 1970 to 1978, the value of these benefits ranged from about $5 billion to $51 billion, with a point estimate of about $22 billion. The national cost estimates by the Council on Environmental Quality, Bureau of Economic Analysis, and McGraw-Hill are provided in section 2. Cost estimates must include not only the end-of-pipe treatment measures, but also the alternatives: changes in product specification, product mix, processes, etc. These types of responses are not generally considered in estimates of national costs. For the period 1970 to 1978, estimates provided in section 3 of national costs of improving ambient air quality ranged from $8 to $9 billion in 1978 dollars. Section 4 concludes that the national benefits for improving ambient air quality exceed the national costs for the average and the high values of benefits, but not for the low estimates. Section 5 discusses the requirements for establishing a national regional computational framework for estimating national benefits and national costs. 49 references, 2 tables

  3. 75 FR 9894 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... in Ambient Air TSP by Hot Plate Acid Extraction and ICP-MS Analysis.'' In this method, total...), extracted on a hot plate with 3M HNO 3 according to 40 CFR Appendix G to part 50, EPA Reference Method for... Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) based on EPA SW-846 Method 6020A. The application for...

  4. Chapter 7: Impact of Nitrogen and Climate Change Interactions on Ambient Air Pollution and Human Health

    EPA Science Inventory

    Nitrogen oxides (NOX) are important components of ambient and indoor air pollution and are emitted from a range of combustion sources, including on-road mobile sources, electric power generators, and non-road mobile sources. While anthropogenic sources dominate, NOX is also forme...

  5. 76 FR 46083 - Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ... Quality Standards for Oxides of Nitrogen and Sulfur; Proposed Rule #0;#0;Federal Register / Vol. 76 , No... RIN 2060-AO72 Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur... nitrogen and oxides of sulfur. Based on its review, EPA proposes to retain the current nitrogen dioxide...

  6. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.4 Section 50.4 Protection of Environment ENVIRONMENTAL....4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). Link to an... to or greater than 0.005 ppm shall be rounded up). (c) Sulfur oxides shall be measured in the...

  7. Hydrogen sulfide (H 2S) in urban ambient air

    NASA Astrophysics Data System (ADS)

    Kourtidis, K.; Kelesis, A.; Petrakakis, M.

    Despite indications of high hydrogen sulfide levels in some urban environments, only sparse measurements have been reported in the literature. Here we present one full year of hydrogen sulfide measurements in an urban traffic site in the city of Thessaloniki, Greece. In this 1-million-population city the H 2S concentrations were surprisingly high, with a mean annual concentration of 8 μg m -3 and wintertime mean monthly concentrations up to 20 μg m -3 (12.9 ppb). Daily mean concentrations in the winter were up to 30 μg m -3 (19.3 ppb), while hourly concentrations were up to 54 μg m -3 (34.8 ppb). During calm (wind velocity < 0.5 m s -1) conditions, mainly encountered during night-time hours, hourly values of H 2S were highly correlated with those of CO ( r2 = 0.75) and SO 2 ( r2 = 0.70), pointing to a common traffic source from catalytic converters. Annual mean concentrations are above the WHO recommendation for odor annoyance; hence, H 2S might play a role to the malodorous episodes that the city occasionally experiences. The high ambient H 2S levels might also be relevant to the implementation of preservation efforts for outdoor marble and limestone historical monuments that have been targeting SO 2 emissions as an atmospheric acidity source, since the measurements presented here suggest that about 19% of the annual sulfur (SO 2 + H 2S) emissions in Thessaloniki are in the form of H 2S.

  8. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... must be made within 100 cm of the air-intake of the engine. The measurement location must be either in... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test...

  9. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... must be made within 100 cm of the air-intake of the engine. The measurement location must be either in... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test...

  10. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers...

  11. 28. Main engine air pump located to port side of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. Main engine air pump located to port side of main engine cylinder beside engine bed. Dynamo lies aft of air pump (at right), pipe at extreme left of image carries lake water to condenser valves. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  12. The National Ambient Air Monitoring Stategy: Rethinking the Role of National Networks

    EPA Science Inventory

    A current re-engineering of the United States routine ambient monitoring networks intended to improve the balance in addressing both regulatory and scientific objectives is addressed in this paper. Key attributes of these network modifications include the addition of collocated ...

  13. Characterization of ambient air quality during a rice straw burning episode.

    PubMed

    Tai-Yi, Yu

    2012-03-01

    Spatiotemporal characteristics and impact of ambient air-quality attributed to open burning of rice straw were analyzed and estimated with measured data. Two multivariate analytic methods, factor analysis and cluster analysis, were adopted to analyze the temporal and spatial impact on ambient air-quality during the rice straw burning episode. Temporal features of three scenarios were cited to compare the concentrations for ambient air-quality between the rice straw burning episode and non-episodes over two typical stations by factor analysis. Factor analysis demonstrated that the first rotational component, identified as being highly correlated to the open burning of rice straw, accounts for about 40% of the concentration variance for ambient air-quality. In typical air-quality stations, the average hourly incremental concentrations between the episode and non-episodes were greater than 300 μg m(-3) for PM(10), 1.0 ppm for CO and 35 ppb for NO(2) during the impact of rice straw burning. Factor analysis presented that the first rotated component was highly correlated with several primary pollutants (NO(2), NMHC, PM(10) and CO) during the rice straw burning episode, while every component was only highly correlated with a unique air pollutant during non-episodes. The delineation isopleths indicated that factor analysis could serve as a better method than cluster analysis and provides cross-county cooperation for local governments located in the same separated district during the rice straw burning season. The results of factor analysis revealed that CO is the best index to demonstrate the impact of rice straw burning than the other six air pollutants measured during the episode. Backward trajectory analysis supplied a cause-effect relationship between measured stations and specific rice planted regions during the rice straw burning episode.

  14. A Direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard

    EPA Science Inventory

    In setting primary ambient air quality standards, the EPA’s responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and ...

  15. 75 FR 39253 - Release of Second Draft Document Related to the Review of the National Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ... AGENCY Release of Second Draft Document Related to the Review of the National Ambient Air Quality... Assessment for the Review of the Particulate Matter National Ambient Air Quality Standards--Second External...: http://www.epa.gov/ttn/naaqs/standards/pm/s_pm_2007_risk.html . The second draft Policy...

  16. 75 FR 51960 - Proposed Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-24

    ... AGENCY 40 CFR Part 51 RIN 2060-AP30 Proposed Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New Source Review Anti-Backsliding Provisions for Former 1-Hour Ozone Standard AGENCY... designated nonattainment for the 1997 8-hour ozone national ambient air quality standard (NAAQS). The...

  17. 75 FR 1566 - Public Hearings for Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... Ambient Air Quality Standards for Ozone AGENCY: Environmental Protection Agency (EPA). ACTION... proposed rule, ``Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone,'' which was... the following Web site: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html for the...

  18. 75 FR 80420 - Reasonable Further Progress Requirements for the 1997 8-Hour Ozone National Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... Ozone National Ambient Air Quality Standard AGENCY: Environmental Protection Agency (EPA). ACTION... 1997 8-hour ozone national ambient air quality standards (NAAQS). Specifically, EPA is proposing that... nitrogen oxides (NO X )] that contribute to ground-level ozone concentrations. B. What should I consider...

  19. 75 FR 44790 - Second Draft Document Related to the Review of the National Ambient Air Quality Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-29

    ... AGENCY Second Draft Document Related to the Review of the National Ambient Air Quality Standards for... Ambient Air Quality Standards--Second External Review Draft. The EPA is extending the comment period for... chapter 4 of the second draft Policy Assessment. The original comment period was to end on August 16,...

  20. 76 FR 48073 - Public Hearing for Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... for Oxides of Nitrogen and Sulfur AGENCY: Environmental Protection Agency (EPA). ACTION: Announcement... titled ``Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur'' which was... ``Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur'' proposed rule should...

  1. Open air mineral treatment operations and ambient air quality: assessment and source apportionment.

    PubMed

    Escudero, M; Alastuey, A; Moreno, T; Querol, X; Pérez, P

    2012-11-01

    We present a methodology for evaluating and quantifying the impact of inhalable mineral dust resuspension close to a potentially important industrial point source, in this case an open air plant producing sand, flux and kaolin in the Capuchinos district of Alcañiz (Teruel, NE Spain). PM(10) levels at Capuchinos were initially high (42 μg m(-3) as the annual average with 91 exceedances of the EU daily limit value during 2007) but subsequently decreased (26 μg m(-3) with 16 exceedances in 2010) due to a reduced demand for minerals from the ceramic industry and construction sector during the first stages of the economic crisis. Back trajectory and local wind pattern analyses revealed only limited contribution from exotic PM sources such as African dust intrusions whereas there was clearly a strong link with the mineral stockpiles of the local industry. This link was reinforced by chemical and mineral speciation and source apportionment analysis which showed a dominance of mineral matter (sum of CO(3)(2-), SiO(2), Al(2)O(3), Ca, Fe, K, Mg, P, and Ti: mostly aluminosilicates) which in 2007 contributed 76% of the PM(10) mass (44 μg m(-3) on average). The contribution from Secondary Inorganic Aerosols (SIA, sum of SO(4)(2-), NO(3)(-) and NH(4)(+)) reached 8.4 μg m(-3), accounting for 14% of the PM(10) mass, similar to the amount of calcareous road dust estimated to be present (8 μg m(-3); 13%). Organic matter and elemental carbon contributed 5.3 μg m(-3) (9%) whereas marine aerosol (Na + Cl) levels were minor with an average concentration of 0.4 μg m(-3) (1% of the PM(10) mass). Finally, chemical and mineralogical analysis of stockpile samples and comparison with filter samples confirmed the local industry to be the major source of ambient PM(10) in the area.

  2. Interlaboratory analysis of high molecular weight organochlorines in ambient air

    NASA Astrophysics Data System (ADS)

    Bidleman, Terry F.

    High volume air samples were collected in Boston, MA, and Columbia, SC using a glass fiber filter — polyurethane foam trap, and the pooled sample extracts from each location were distributed among nine laboratories for organochlorine analysis. Polychlorinated biphenyls (PCB) were reported by all laboratories, with relative standard deviations (RSDs) ranging from 26-39 % for total PCB. The total PCB concentration in Boston was 7.1 ng m -3, compared to 4.4 ng m -3 in Columbia. Other organochlorines identified by three or more laboratories included hexachlorobenzene and the pesticides DDT, DDE, chlordane, dieldrin, endrin, hexachlorocyclohexane, and polychloroterpenes. RSDs for most pesticides ranged from 35-75% and as high as 116% for polychloroterpenes (quantified as toxaphene). In general, pesticide levels were an order of magnitude higher in Columbia than in Boston.

  3. Lung cancer and ambient air pollution in Helsinki

    SciTech Connect

    Poenkae, A.; Pukkala, E.; Hakulinen, T.

    1993-12-31

    In a record linkage study between the population register of the City of Helsinki and the Finnish Cancer Registry, standardized incidence ratios (SIR) of lung cancer for 33 subareas of Helsinki were estimated in order to determine the regional differences and the extent to which these were the effects of socioeconomic factors and air pollution. In addition, the SIRs for people living along main streets were calculated. In 1975-86, 2,439 cases of lung cancer among males and 765 among females were diagnosed in a population of 0.5 million inhabitants. In the subareas, the SIR for males varied from 0.56 to 1.56 and for females from 0.29 to 3.17. A strong inverse association, most likely due to smoking, was observed between lung cancer and average educational level. The levels of sulfur dioxide (SO{sub 2}) and nitrogen dioxide (NO{sub 2}) in the air of various parts of the city were assessed from mathematical models. After adjustment for age, sex, and level of education, the lung cancer risk increased slightly, but nonsignificantly, with increasing SO{sub 2} concentration, being 1.3% higher in the subareas with the highest SO{sub 2} concentrations as compared with the subareas with the lowest concentrations. There was no consistent relation between the concentration of NO{sub 2} and the incidence of lung cancer. The SIR for people living along main streets was slightly lower than for the whole city, varying from 0.39 to 1.31 for males and from 0.24 to 1.51 for females. This variation was likewise mainly attributable to average educational level, but the multiple regression model also revealed slightly, although nonsignificantly, higher SIRs along the streets with denser road traffic. 51 refs., 6 figs., 2 tabs.

  4. Effect of fireworks on ambient air quality in Malta

    NASA Astrophysics Data System (ADS)

    Camilleri, Renato; Vella, Alfred J.

    2010-11-01

    Religious festivals ( festas) in the densely populated Maltese archipelago (Central Mediterranean) are ubiquitous during summer when 86 of them are celebrated between June and October, each involving the burning of fireworks both in ground and aerial displays over a period of 3 days or longer per festival. We assessed the effect of fireworks on the air quality by comparing PM 10 and its content of Al, Ba, Cu, Sr and Sb which materials are used in pyrotechnic compositions. PM 10 was collected mainly from two sites, one in Malta (an urban background site) and the other in Gozo (a rural site) during July-August 2005 when 59 feasts were celebrated and September-October 2005 when only 11 feasts occurred. For both Malta and Gozo, PM 10 and metal concentration levels measured as weekly means were significantly higher during July-August compared to September-October and there exist strong correlations between PM 10 and total metal content. Additionally, for Malta dust, Al, Ba, Cu and Sr correlated strongly with each other and also with total concentration of all five metals. The same parameters measured in April 2006 in Malta were at levels similar to those found in the previous October. Ba and Sb in dust from the urban background site in Malta during July-August were at comparable or higher concentration than recently reported values in PM 10 from a heavily-trafficked London road and this suggests that these metals are locally not dominated by sources from roadside materials such as break liner wear but more likely by particulate waste from fireworks. Our findings point to the fact that festa firework displays contribute significantly and for a prolonged period every year to airborne dust in Malta where PM 10 is an intractable air quality concern. The presence in this dust of elevated levels of Ba and especially Sb, a possible carcinogen, is of concern to health.

  5. Application of a dry-gas meter for measuring air sample volumes in an ambient air monitoring network

    SciTech Connect

    Fritz, Brad G.

    2009-05-24

    Ambient air monitoring for non-research applications (e.g. compliance) occurs at locations throughout the world. Often, the air sampling systems employed for these purposes employee simple yet robust equipment capable of handling the rigors of demanding sampling schedules. At the Hanford Site (near Richland, Washington) concentrations of radionuclides in ambient air are monitored continuously at 44 locations. In 2004, mechanical dry-gas meters were incorporated into the Hanford Site ambient air sample collection system to allow the direct measurement of sample volumes. These meters replaced a portable airflow measurement system that required two manual flow measurements and a sample duration measurement to determine sample volume. A six-month evaluation of the dry-gas meters compared sample volumes calculated using the original flow rate method to the direct sample volume measurement (new method). The results of the evaluation indicate that use of the dry-gas meters result in accurate sample volume measurements and provide greater confidence in the measured sample volumes. In several years of in-network use, the meters have proven to be reliable and have resulted in an improved sampling system.

  6. Optimized arrangement of constant ambient air monitoring stations in the Kanto region of Japan.

    PubMed

    Shirato, Shintaro; Iizuka, Atsushi; Mizukoshi, Atsushi; Noguchi, Miyuki; Yamasaki, Akihiro; Yanagisawa, Yukio

    2015-03-10

    Continuous ambient air monitoring systems have been introduced worldwide. However, such monitoring forces autonomous communities to bear a significant financial burden. Thus, it is important to identify pollutant-monitoring stations that are less efficient, while minimizing loss of data quality and mitigating effects on the determination of spatiotemporal trends of pollutants. This study describes a procedure for optimizing a constant ambient air monitoring system in the Kanto region of Japan. Constant ambient air monitoring stations in the area were topologically classified into four groups by cluster analysis and principle component analysis. Then, air pollution characteristics in each area were reviewed using concentration contour maps and average pollution concentrations. We then introduced three simple criteria to reduce the number of monitoring stations: (1) retain the monitoring station if there were similarities between its data and average data of the group to which it belongs; (2) retain the station if its data showed higher concentrations; and (3) retain the station if the monitored concentration levels had an increasing trend. With this procedure, the total number of air monitoring stations in suburban and urban areas was reduced by 36.5%. The introduction of three new types of monitoring stations is proposed, namely, mobile, for local non-methane hydrocarbon pollution, and Ox-prioritized.

  7. Effects of ambient room temperature on cold air cooling during laser hair removal.

    PubMed

    Ram, Ramin; Rosenbach, Alan

    2007-09-01

    Forced air cooling is a well-established technique that protects the epidermis during laser heating of deeper structures, thereby allowing for increased laser fluences. The goal of this prospective study was to identify whether an elevation in ambient room temperature influences the efficacy of forced air cooling. Skin surface temperatures were measured on 24 sites (12 subjects) during cold air exposure in examination rooms with ambient temperatures of 72 degrees F (22.2 degrees C) and 82 degrees F (27.8 degrees C), respectively. Before cooling, mean skin surface temperature was 9 degrees F (5 degrees C) higher in the warmer room (P < 0.01). Immediately after exposure to forced air cooling (within 1 s), the skin surface temperature remained considerably higher (10.75 degrees F, or 5.8 degrees C, P < 0.01) in the warmer room. We conclude that forced air cooling in a room with an ambient temperature of 82 degrees F (27.8 degrees C) is not as effective as in a room that is at 72 degrees F (22.2 degrees C).

  8. Ambient air pollution and congenital heart defects in Lanzhou, China

    NASA Astrophysics Data System (ADS)

    Jin, Lan; Qiu, Jie; Zhang, Yaqun; Qiu, Weitao; He, Xiaochun; Wang, Yixuan; Sun, Qingmei; Li, Min; Zhao, Nan; Cui, Hongmei; Liu, Sufen; Tang, Zhongfeng; Chen, Ya; Yue, Li; Da, Zhenqiang; Xu, Xiaoying; Huang, Huang; Liu, Qing; Bell, Michelle L.; Zhang, Yawei

    2015-07-01

    Congenital heart defects are the most prevalent type of birth defects. The association of air pollution with congenital heart defects is not well understood. We investigated a cohort of 8969 singleton live births in Lanzhou, China during 2010-2012. Using inverse distance weighting, maternal exposures to particulate matter with diameters ≤10 μm (PM10), nitrogen dioxide (NO2), and sulfur dioxide (SO2) were estimated as a combination of monitoring station levels for time spent at home and in a work location. We used logistic regression to estimate the associations, adjusting for maternal age, education, income, BMI, disease, folic acid intake and therapeutic drug use, and smoking; season of conception, fuel used for cooking and temperature. We found significant positive associations of Patent Ductus Arteriosus (PDA) with PM10 during the 1st trimester, 2nd trimester and the entire pregnancy (OR 1st trimester = 3.96, 95% confidence interval (CI): 1.36, 11.53; OR 2nd trimester = 3.59, 95% CI: 1.57, 8.22; OR entire pregnancy = 2.09, 95% CI: 1.21, 3.62, per interquartile range (IQR) increment for PM10 (IQR = 71.2, 61.6, and 27.4 μg m-3, respectively)), and associations with NO2 during 2nd trimester and the entire pregnancy (OR 2nd trimester = 1.92, 95% CI: 1.11, 3.34; OR entire pregnancy = 2.32, 95% Cl: 1.14, 4.71, per IQR increment for NO2 (IQR = 13.4 and 10.9 μg m-3, respectively)). The associations for congenital malformations of the great arteries and pooled cases showed consistent patterns. We also found positive associations for congenital malformations of cardiac septa with PM10 exposures in the 2nd trimester and the entire pregnancy, and SO2 exposures in the entire pregnancy. Results indicate a health burden from maternal exposures to air pollution, with increased risk of congenital heart defects.

  9. Impact of vehicular exhaust on ambient air quality of Rohtak city, India.

    PubMed

    Shukla, Vineeta; Dalal, Poonam; Chaudhry, Dhruva

    2010-11-01

    In the present study, ambient air quality of Rohtak city (Haryana) was monitored by High Volume Sampler. The selected parameters to judge the quality of air were Sulphur dioxide (SO2), Nitrogen dioxide NO), Ozone (O3) and Suspended particulate matters (SPM) which give a fair idea of pollution load carried by the air. The monitoring data were collected from six sites randomly selected in Rohtak city. Sulphur dioxide was found below the permissible limits of National Ambient Avo Quality Standards (NAAQS) at all the sites. Higher concentration of SO2 was observed during winter in comparison to summer and monsoon seasons. Nitrogen dioxide concentration was found to be above the prescribed standards of NAAOS at four sites in winter season. Ozone concentration was found below the prescribed standards (NAAOS), but its concentration was higher in summer season as compared to winter. Suspended particulate matter concentration was observed above the safety limits at all the sites in all three seasons.

  10. Adaptive Preheating Duration Control for Low-Power Ambient Air Quality Sensor Networks

    PubMed Central

    Baek, Yoonchul; Atiq, Mahin K.; Kim, Hyung Seok

    2014-01-01

    Ceramic gas sensors used for measuring ambient air quality have features suitable for practical applications such as healthcare and air quality management, but have a major drawback—large power consumption to preheat the sensor for accurate measurements. In this paper; the adaptive preheating duration control (APC) method is proposed to reduce the power consumption of ambient air quality sensor networks. APC reduces the duration of unnecessary preheating, thereby alleviating power consumption. Furthermore, the APC can allow systems to meet user requirements such as accuracy and periodicity factor when detecting the concentration of a target gas. A performance evaluation of the power consumption of gas sensors is conducted with various user requirements and factors that affect the preheating duration of the gas sensor. This shows that the power consumption of the APC is lower than that of continuous power supply methods and constant power supply/cutoff methods. PMID:24658619

  11. Adaptive preheating duration control for low-power ambient air quality sensor networks.

    PubMed

    Baek, Yoonchul; Atiq, Mahin K; Kim, Hyung Seok

    2014-03-20

    Ceramic gas sensors used for measuring ambient air quality have features suitable for practical applications such as healthcare and air quality management, but have a major drawback-large power consumption to preheat the sensor for accurate measurements. In this paper; the adaptive preheating duration control (APC) method is proposed to reduce the power consumption of ambient air quality sensor networks. APC reduces the duration of unnecessary preheating, thereby alleviating power consumption. Furthermore, the APC can allow systems to meet user requirements such as accuracy and periodicity factor when detecting the concentration of a target gas. A performance evaluation of the power consumption of gas sensors is conducted with various user requirements and factors that affect the preheating duration of the gas sensor. This shows that the power consumption of the APC is lower than that of continuous power supply methods and constant power supply/cutoff methods.

  12. FY 1994 ambient air monitoring report for McMurdo Station, Antarctica

    SciTech Connect

    Lugar, R.M.

    1994-12-01

    This report presents the results of ambient air monitoring performed during the 1994 fiscal year (FY 1994) in the vicinity of McMurdo Station, Antarctica. Routine monitoring was performed during the 1993-1994 austral summer at three locations for airborne particulate matter less than 10 micrometers (PM-10) and at two locations for carbon monoxide (CO), sulfur dioxide (SO{sub 2}), and nitrogen oxides (NO, NO{sub 2}, and NO{sub x}). Selected PM-10 filters were analyzed for arsenic, beryllium, cadmium, chromium, lead, mercury, and nickel. Additional air samples were collected at three McMurdo area locations and at Black Island for determination of the airborne concentration of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Sampling site selection, sampling procedures, and quality assurance procedures used were consistent with US Environmental Protection Agency guidance for local ambient air quality networks.

  13. Environmental dust effects on aluminum surfaces in humid air ambient

    PubMed Central

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-01-01

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems. PMID:28378798

  14. Environmental dust effects on aluminum surfaces in humid air ambient.

    PubMed

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-04-05

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems.

  15. The Comparative Reactivity Method - a new tool to measure total OH Reactivity in ambient air

    NASA Astrophysics Data System (ADS)

    Sinha, V.; Williams, J.; Crowley, J. N.; Lelieveld, J.

    2008-04-01

    Hydroxyl (OH) radicals play a vital role in maintaining the oxidizing capacity of the atmosphere. To understand variations in OH radicals both source and sink terms must be understood. Currently the overall sink term, or the total atmospheric reactivity to OH, is poorly constrained. Here, we present a new on-line method to directly measure the total OH reactivity (i.e.~total loss rate of OH radicals) in a sampled air mass. In this method, a reactive molecule (X), not normally present in air, is passed through a glass reactor and its concentration is monitored with a suitable detector. OH radicals are then introduced in the glass reactor at a constant rate to react with X, first in the presence of zero air and then in the presence of ambient air containing VOCs and other OH reactive species. Comparing the amount of X exiting the reactor with and without the ambient air allows the air reactivity to be determined. In our existing set up, X is pyrrole and the detector used is a proton transfer reaction mass spectrometer. The present dynamic range for ambient air reactivity is about 6 to 300 s-1, with an overall maximum uncertainty of 25% above 8 s-1 and up to 50% between 6-8 s-1. The system has been tested and calibrated with different single and mixed hydrocarbon standards showing excellent linearity and accountability with the reactivity of the standards. Potential interferences such as high NO in ambient air, varying relative humidity and photolysis of pyrrole within the setup have also been investigated. While interferences due changing humidity and photolysis of pyrrole are easily overcome by ensuring that humidity in the set up does not change drastically and the photolytic loss of pyrrole is measured and taken into account, respectively, NO>10 ppb in ambient air remains a significant interference for the current configuration of the instrument. Field tests in the tropical rainforest of Suriname (~53 s

  16. Clean Air Act Vehicle and Engine Enforcement Case Resolutions

    EPA Pesticide Factsheets

    The Clean Air Act requires new engines and equipment sold or distributed in the United States to be certified to meet EPA-established emissions requirements to protect public health and the environment from air pollution.

  17. The variation of the relative humidity of air released from canisters after ambient sampling

    SciTech Connect

    McClenny, W.A.; Schmidt, S.M.; Kronmiller, K.G.

    1997-12-31

    Dalton`s Law of partial pressures and the hypothesis that water vapor equilibrium above a canister surface is identical to that established above liquid water are used to predict the variation of the percent relative humidity (%RH) of air released from canisters used in ambient air sampling, typically 6L canisters pressurized with 18L of air. During sampling, some water vapor is adsorbed on the canister wall. When (and if) the water vapor partial pressure exceeds its saturation vapor pressure, water vapor condensation begins and the condensation rate equals the sampling rate of water vapor into the canister. Under constant temperature conditions, the air subsequently released from the canister is less humid than the original sample, following the relationship, %RH = 100% (6L/V{sub s}) for V{sub s} > V{sub r} where V{sub s} is the residual air volume and V{sub r} is the residual air volume at which water is completely removed (except for adsorbed water vapor) from the canister wall. For V{sub s} < V{sub r} the %RH is constant and equal to its value at V{sub r}, V{sub r} is shown to depend on the %RH of the ambient air sample. Experimental values to agree reasonably well with predictions; however, experimental values were systematically lower than predicted especially when ambient air with mid-range %RH was sampled. This difference is related to the mass of water vapor remaining adsorbed on the canister surface as water evaporates. This paper has been reviewed in accordance with the U.S. Environmental Protection Agency`s peer and administrative review policies and approved for presentation and publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

  18. Quantile-based Bayesian maximum entropy approach for spatiotemporal modeling of ambient air quality levels.

    PubMed

    Yu, Hwa-Lung; Wang, Chih-Hsin

    2013-02-05

    Understanding the daily changes in ambient air quality concentrations is important to the assessing human exposure and environmental health. However, the fine temporal scales (e.g., hourly) involved in this assessment often lead to high variability in air quality concentrations. This is because of the complex short-term physical and chemical mechanisms among the pollutants. Consequently, high heterogeneity is usually present in not only the averaged pollution levels, but also the intraday variance levels of the daily observations of ambient concentration across space and time. This characteristic decreases the estimation performance of common techniques. This study proposes a novel quantile-based Bayesian maximum entropy (QBME) method to account for the nonstationary and nonhomogeneous characteristics of ambient air pollution dynamics. The QBME method characterizes the spatiotemporal dependence among the ambient air quality levels based on their location-specific quantiles and accounts for spatiotemporal variations using a local weighted smoothing technique. The epistemic framework of the QBME method can allow researchers to further consider the uncertainty of space-time observations. This study presents the spatiotemporal modeling of daily CO and PM10 concentrations across Taiwan from 1998 to 2009 using the QBME method. Results show that the QBME method can effectively improve estimation accuracy in terms of lower mean absolute errors and standard deviations over space and time, especially for pollutants with strong nonhomogeneous variances across space. In addition, the epistemic framework can allow researchers to assimilate the site-specific secondary information where the observations are absent because of the common preferential sampling issues of environmental data. The proposed QBME method provides a practical and powerful framework for the spatiotemporal modeling of ambient pollutants.

  19. Closed-loop air cooling system for a turbine engine

    DOEpatents

    North, William Edward

    2000-01-01

    Method and apparatus are disclosed for providing a closed-loop air cooling system for a turbine engine. The method and apparatus provide for bleeding pressurized air from a gas turbine engine compressor for use in cooling the turbine components. The compressed air is cascaded through the various stages of the turbine. At each stage a portion of the compressed air is returned to the compressor where useful work is recovered.

  20. CO2 Capture from Ambient Air by Crystallization with a Guanidine Sorbent.

    PubMed

    Seipp, Charles A; Williams, Neil J; Kidder, Michelle K; Custelcean, Radu

    2017-01-19

    Carbon capture and storage is an important strategy for stabilizing the increasing concentration of atmospheric CO2 and the global temperature. A possible approach toward reversing this trend and decreasing the atmospheric CO2 concentration is to remove the CO2 directly from air (direct air capture). Herein we report a simple aqueous guanidine sorbent that captures CO2 from ambient air and binds it as a crystalline carbonate salt by guanidinium hydrogen bonding. The resulting solid has very low aqueous solubility (Ksp =1.0(4)×10(-8) ), which facilitates its separation from solution by filtration. The bound CO2 can be released by relatively mild heating of the crystals at 80-120 °C, which regenerates the guanidine sorbent quantitatively. Thus, this crystallization-based approach to CO2 separation from air requires minimal energy and chemical input, and offers the prospect for low-cost direct air capture technologies.

  1. [Assessment of Moscow population health risk from exposure to ambient air suspended matter].

    PubMed

    Novikov, S M; Ivanenko, A V; Volkova, I F; Kornienko, A P; Skvortsova, N S

    2009-01-01

    Ambient air pollution by suspended matter is an environmental factor that has the greatest influence on the health status of the majority of the Russian Federation's population. There is extensive epidemiological and clinical evidence suggesting that ambient air pollution by suspended matter and its fine-dispersed fractions PM10 and PM2.5 in particular, poses a serious threat to human health. The existing Russian single and average daily maximum permissible concentrations of suspended matter are not a high risk from this type of ambient air pollution and fail to assess human health damage in full measure. To reduce the concentrations of suspended matter and their action on man is currently the worldwide priority task whose performance will save much money. There is a need to change an air pollution monitoring system (continuous monitoring of fine suspended matter of PM10 and PM2.5), as well as to substantiate and introduce Russian hygienic standards for fine suspended matter (PM10 and PM2.5).

  2. New screening approach for risk assessment of pesticides in ambient air

    NASA Astrophysics Data System (ADS)

    Yusà, Vicent; Coscollà, Clara; Millet, Maurice

    2014-10-01

    We present a novel screening approach for inhalation risk assessment of currently used pesticides (CUPs) in ambient air, based on the measurements of pesticide levels in the inhalable fraction of the particulate matter (PM10). Total concentrations in ambient air (gas + particle phases) were estimated using a theoretical model of distribution of semi-volatile organic compounds between the gas and the particulate phase based on the octanol-air partition (Koa) of each pesticide. The proposed approach was used in a pilot study conducted in a rural station in Valencia (Spain) from April through to October 2010. Twenty out of 82 analysed pesticides were detected in average concentrations ranging from 1.63 to 117.01 pg m-3. For adults, children and infants the estimated chronic inhalation risk, expressed as Hazard Quotient (HQ) was <1 for all pesticides. Likewise, the cumulative exposure for detected organophosphorus, pyrethroids and carbamates pesticides, was estimated using as metrics the Hazard Index (HI), which was less than 1 for the three families of pesticides assessed. The cancer risk estimated for the detected pesticides classified as Likely or Possible carcinogens was less than 1.15E-7 for infants. In our opinion, the screening approach proposed could be used in the monitoring and risk assessment of pesticides in ambient air.

  3. Ambient particulate air pollution from vehicles promotes lipid peroxidation and inflammatory responses in rat lung.

    PubMed

    Pereira, C E L; Heck, T G; Saldiva, P H N; Rhoden, C R

    2007-10-01

    Oxidative stress plays a major role in the pathogenesis of particle-dependent lung injury. Ambient particle levels from vehicles have not been previously shown to cause oxidative stress to the lungs. The present study was conducted to a) determine whether short-term exposure to ambient levels of particulate air pollution from vehicles elicits inflammatory responses and lipid peroxidation in rat lungs, and b) determine if intermittent short-term exposures (every 4 days) induce some degree of tolerance. Three-month-old male Wistar rats were exposed to ambient particulate matter (PM) from vehicles (N = 30) for 6 or 20 continuous hours, or for intermittent (5 h) periods during 20 h for 4 consecutive days or to filtered air (PM <10 microm; N = 30). Rats continuously breathing polluted air for 20 h (P-20) showed a significant increase in the total number of leukocytes in bronchoalveolar lavage compared to control (C-20: 2.61 x 105 +/- 0.51;P-20: 5.01 x 105 +/- 0.81; P < 0.05) and in lipid peroxidation ([MDA] nmol/mg protein: C-20: 0.148 +/- 0.01; P-20: 0.226 +/- 0.02; P < 0.05). Shorter exposure (6 h) and intermittent 5-h exposures over a period of 4 days did not cause significant changes in leukocytes. Lipid damage resulting from 20-h exposure to particulate air pollution did not cause a significant increase in lung water content. These data suggest oxidative stress as one of the mechanisms responsible for the acute adverse respiratory effects of particles, and suggest that short-term inhalation of ambient particulate air pollution from street with high automobile traffic represents a biological hazard.

  4. The Comparative Reactivity Method - a new tool to measure total OH reactivity in ambient air

    NASA Astrophysics Data System (ADS)

    Sinha, V.; Williams, J.; Crowley, J. N.; Lelieveld, J.

    2007-12-01

    Hydroxyl (OH) radicals play a vital role in maintaining the oxidizing capacity of the atmosphere. To understand variations in OH radicals both source and sink terms must be understood. Currently the overall sink term, or the total atmospheric reactivity to OH, is poorly constrained. Here, we present a new on-line method to directly measure the total OH reactivity (i.e.~total loss rate of OH radicals) in a sampled air mass. In this method, a reactive molecule (X), not normally present in air, is passed through a glass reactor and its concentration is monitored with a suitable detector. OH radicals are then introduced in the glass reactor at a constant rate to react with X, first in the presence of zero air and then in the presence of ambient air containing VOCs and other OH reactive species. Comparing the amount of X exiting the reactor with and without the ambient air allows the air reactivity to be determined. In our existing set up, X is pyrrole and the detector used is a proton transfer reaction mass spectrometer. The present dynamic range for ambient air reactivity is about 6 to 300 s-1. The system has been tested and calibrated with different single and mixed hydrocarbon standards showing excellent linearity and accountability with the reactivity of the standards. Field tests in the tropical rainforest of Suriname (~53 s-1) and the urban atmosphere of Mainz (~10 s-1) Germany, show the promise of the new method and indicate that a significant fraction of OH reactive species in the tropical forests is likely missed by current measurements. Suggestions for improvements to the technique and future applications are discussed.

  5. Biomass burning contribution to ambient air particulate levels at Navrongo in the Savannah zone of Ghana.

    PubMed

    Ofosu, Francis G; Hopke, Philip K; Aboh, Innocent J K; Bamford, Samuel A

    2013-09-01

    The concentrations of airborne particulate matter (PM) in Navrongo, a town in the Sahel Savannah Zone of Ghana, have been measured and the major sources have been identified. This area is prone to frequent particulate pollution episodes due to Harmattan dust and biomass burning, mostly from annual bushfires. The contribution of combustion emissions, particularly from biomass and fossil fuel, to ambient air particulate loadings was assessed. Sampling was conducted from February 2009 to February 2010 in Navrongo. Two Gent samplers were equipped to collect PM10 in two size fractions, coarse (PM10-2.5) and fine (PM2.5). Coarse particles are collected on a coated, 8-microm-pore Nuclepore filter. Fine particle samples were sampled with 47-mm-diameter Nuclepore and quartz filters. Elemental carbon (EC) and organic carbon (OC) concentrations were determined from the quartz filters using thermal optical reflectance (IMPROVE/TOR) methods. Elements were measured on the fine-particle Nuclepore filters using energy-dispersive x-ray fluorescence. The average PM2.5 mass concentration obtained at Navrongo was 32.3 microg/m. High carbonaceous concentrations were obtained from November to March, the period of Harmattan dust and severe bush fires. Total carbon was found to contribute approximately 40% of the PM2.5 particulate mass. Positive matrix factorization (PMF) suggested six major sources contributing to the PM2.5 mass. They are two stroke engines, gasoline emissions, soil dust, diesel emissions, biomass burning, and resuspended soil dust. Biomass combustion (16.0%) was identified as second most important source next to soil dust at Navrongo.

  6. Statistical Engineering in Air Traffic Management Research

    NASA Technical Reports Server (NTRS)

    Wilson, Sara R.

    2015-01-01

    NASA is working to develop an integrated set of advanced technologies to enable efficient arrival operations in high-density terminal airspace for the Next Generation Air Transportation System. This integrated arrival solution is being validated and verified in laboratories and transitioned to a field prototype for an operational demonstration at a major U.S. airport. Within NASA, this is a collaborative effort between Ames and Langley Research Centers involving a multi-year iterative experimentation process. Designing and analyzing a series of sequential batch computer simulations and human-in-the-loop experiments across multiple facilities and simulation environments involves a number of statistical challenges. Experiments conducted in separate laboratories typically have different limitations and constraints, and can take different approaches with respect to the fundamental principles of statistical design of experiments. This often makes it difficult to compare results from multiple experiments and incorporate findings into the next experiment in the series. A statistical engineering approach is being employed within this project to support risk-informed decision making and maximize the knowledge gained within the available resources. This presentation describes a statistical engineering case study from NASA, highlights statistical challenges, and discusses areas where existing statistical methodology is adapted and extended.

  7. Variations of the ambient dose equivalent rate in the ground level air.

    PubMed

    Lebedyte, M; Butkus, D; Morkŭnas, G

    2003-01-01

    The ambient dose equivalent rate is caused by ionizing radiation of radionuclides in the atmosphere and on the ground surface as well as by cosmic radiation. Seasonal and diurnal variations of the ambient dose equivalent rate (ADER) in the ground level air are influenced by the concentration of 222Rn daughters. The 222Rn concentration in the ground level atmosphere, in turn, depends on the rate of the 222Rn exhalation from soil and turbulent air mixing. Its diurnal and seasonal variations depend on meteorological conditions. The aim of this study is to estimate the influence of variations of the rate of the 222Rn exhalation from soil and its concentrations in the ground level air on variations of ADER in the ground level air, as well as the dependence of these parameters on meteorological conditions. The 222Rn diffusion coefficient and its exhalation rate in undisturbed loamy soil have been determined. The 222Rn concentration in the soil air and its concentration in the ground level air correlate inversely (correlation coefficient is r = -0.62). The main factors determining the 222Rn exhalation from soil are: the soil temperature (r = 0.64), the difference in temperature of soil and air (r = 0.57), and the precipitation amount (r = 0.50). The intensity of gamma radiation in the ground level air is mostly related to the 222Rn concentration in the air (r = 0.62), while the effect of the exhalation rate from soil is relatively low (r = 0.36). It has been shown that ADER due to 222Rn progeny causes only 7-16% of the total ADER and influences its variation. The comparison of variations of ADER due to 222Rn progeny and the total ADER during several years shows that these parameters correlate positively.

  8. Short-term concentration of CO2 in the ambient air of Nagpur city.

    PubMed

    Manuel, Jovita A; Gajghate, D G; Hasan, M Z; Singh, R N

    2002-07-01

    Carbon dioxide concentration is an index of total amount of combustion and natural ventilation in an urban environment and therefore required more careful attention for assessment of CO2 level in air environment. First time, an attempt was made to monitor CO2 levels in Ambient Air of Nagpur during August 2001-December 2001 at Industrial, Commercial and Residential sites. The largest amount of CO2 occurred at night due to darkness which depresses the photosynthesis to its lowest level. The lowest concentration of CO2 was showed in afternoon hours when photosynthesis is at its maximum. The average concentration of CO2 was found to be 361, 366 and 339 ppm at Industrial, Commercial and Industrial sites respectively. This generation of database of ambient CO2 will help to formulate the strategy for prevention of global warming phenomenon.

  9. Surveillance programme on dioxin levels in ambient air sites in Catalonia (Spain).

    PubMed

    Abad, Esteban; Caixach, Josep; Rivera, Josep; Gustems, Lluís; Massagué, Guillem; Puig, Oriol

    2002-11-01

    As part of a survey programme conducted by the Environment Department of the Autonomous Government of Catalonia in collaboration with the Spanish Council for Scientific Research (CSIC), dioxin concentrations in ambient air were measured in the four provinces of Catalonia (Spain). The study was also performed with the intention of providing data as a basis for future monitoring and evaluation of temporal trends in ambient air. Thus, 91 samples were collected in 25 different sites (rural, urban, suburban and industrial) between 1994 and 2000. The levels revealed a variable content of PCDDs/PCDFs depending both on the area and the contamination source. In particular, industrial areas presented levels ranging from 18 to 954 fg I-TEQ/m3. However, findings in urban and suburban sites varied between 13 and 357 fg I-TEQ/m3. As expected, the lowest levels were found in rural areas with levels between 5 and 125 fg I-TEQ/m3.

  10. Technical specification for transferring ambient air monitoring data to the Oak Ridge Environmental Information System (OREIS)

    SciTech Connect

    1995-06-01

    In September 1994, a team was formed to develop, document, and implement technical specifications for transmitting ambient air environmental compliance and monitoring data to the Oak Ridge Environmental Information System (OREIS). The approach used to transmit this data is documented in the {open_quotes}Plan for Integrating Environmental Compliance and Monitoring Data into OREIS.{close_quotes} This plan addresses the consolidated data requirements defined by the Federal Facility Agreement (FFA) and the Tennessee Oversight Agreement (TOA) as they pertain to environmental compliance and monitoring data maintained by Energy Systems` Oak Ridge Environmental Management organizations. Ibis document describes. the requirements, responsibilities, criteria, and format for transmitting ambient air compliance and monitoring data to OREIS.

  11. Relationship between polynuclear aromatic hydrocarbons in ambient air and 1-hydroxypyrene in human urine

    SciTech Connect

    Zhao, Z.H.; Quan, W.Y.; Tian, D.H. )

    1992-10-01

    The relationship between urinary 1-hydroxypyrene and ambient polynuclear aromatic hydrocarbons (PAHs) was investigated with several groups of volunteers carrying personal air samplers. All the results demonstrate that there is a statistically significant correlation between 1-hydroxypyrene in human urine and pyrene and benzo(a)pyrene in ambient air. Smoking was found not to interfere this correlation when the smokers consume less than 20 cigarettes daily. Different sources of PAH pollution, such as certain industries and coal-burning, present their influence on 1-hydroxypyrene in their specific ways. It is suggested that 1-hydroxypyrene in human urine is an effective biological monitoring index for the assessment of human exposure to PAHs. 18 refs., 7 figs., 6 tabs.

  12. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  13. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  14. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  15. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  16. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix explains... ambient air quality standards for Oxides of Sulfur as measured by Sulfur Dioxide (“SO2 NAAQS”)...

  17. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix explains... ambient air quality standards for Oxides of Sulfur as measured by Sulfur Dioxide (“SO2 NAAQS”)...

  18. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix explains... ambient air quality standards for Oxides of Sulfur as measured by Sulfur Dioxide (“SO2 NAAQS”)...

  19. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix explains... ambient air quality standards for Oxides of Sulfur as measured by Sulfur Dioxide (“SO2 NAAQS”)...

  20. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix explains... ambient air quality standards for Oxides of Sulfur as measured by Sulfur Dioxide (“SO2 NAAQS”)...

  1. Ambient air monitoring plan for Ciudad Acuna and Piedra Negras, Coahuila, Mexico. Final report

    SciTech Connect

    Winberry, J.; Henning, L.; Crume, R.

    1998-01-01

    The Cities of Ciudad Acuna and Piedras Negras and the State of Coahuila in Mexico are interested in improving ambient air quality monitoring capabilities in the two cities through the establishment of a network of ambient air monitors. The purpose of the network is to characterize population exposure to potentially harmful air contaminants, possibly including sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), ozone (O{sub 3}), carbon monoxide (CO), total suspended particulate matter (TSP), particulate matter with aerodynamic diameter less than 100 micrometers PM-10, and lead. This report presents the results of an evaluation of existing air quality monitoring equipment and facilities in Ciudad Acuna and Piedras Negras. Additionally, the report presents recommendations for developing an air quality monitoring network for PM-10, SO{sub 2}, lead, and ozone in these cities, using a combination of both new and existing equipment. The human resources currently available and ultimately needed to operate and maintain the network are also discussed.

  2. Bronchomotor response to cold air or helium-oxygen at normal and high ambient pressures.

    PubMed

    Jammes, Y; Burnet, H; Cosson, P; Lucciano, M

    1988-05-01

    Effects of inhalation of cold air or helium-oxygen mixture on lung resistance (RL) were studied in anesthetized and tracheotomized rabbits under normal ambient pressure and in human volunteers under normo- and hyperbaric conditions. In artificially ventilated rabbits, an increase in RL occurred when the tracheal temperature fell to 10 degrees C. This effect was more than double with helium breathing compared to air, despite a lower respiratory heat loss by convection (Hc) with helium. In 3 normal humans, inhalation of cold air (mouth temperature = 8 degrees C) at sea level had no effect on RL value. However, with a helium-nitrogen-oxygen mixture, a weak but significant increase in RL due to cold gas breathing was measured in 1 subject at 2 ATA and in 2 individuals at 3.5 ATA. The density of inhaled gas mixture (air or He-N2-O2) was near the same in the three circumstances (1, 2, and 3.5 ATA) but Hc value increased with helium. At 8 ATA a 30-55% increase in RL occurred in the 3 divers during inhalation of cold gas (Hc was multiplied by 6 compared to air at sea level) and at 25 ATA the cold-induced bronchospasm ranged between 38 and 95% (Hc multiplied by 27). Thus, in rabbits and humans helium breathing enhanced the cold-induced increase in RL at normal or elevated ambient pressure, and this effect was interpreted as resulting from different mechanisms in the two circumstances.

  3. Single-step ambient-air synthesis of graphene from renewable precursors as electrochemical genosensor.

    PubMed

    Seo, Dong Han; Pineda, Shafique; Fang, Jinghua; Gozukara, Yesim; Yick, Samuel; Bendavid, Avi; Lam, Simon Kwai Hung; Murdock, Adrian T; Murphy, Anthony B; Han, Zhao Jun; Ostrikov, Kostya Ken

    2017-01-30

    Thermal chemical vapour deposition techniques for graphene fabrication, while promising, are thus far limited by resource-consuming and energy-intensive principles. In particular, purified gases and extensive vacuum processing are necessary for creating a highly controlled environment, isolated from ambient air, to enable the growth of graphene films. Here we exploit the ambient-air environment to enable the growth of graphene films, without the need for compressed gases. A renewable natural precursor, soybean oil, is transformed into continuous graphene films, composed of single-to-few layers, in a single step. The enabling parameters for controlled synthesis and tailored properties of the graphene film are discussed, and a mechanism for the ambient-air growth is proposed. Furthermore, the functionality of the graphene is demonstrated through direct utilization as an electrode to realize an effective electrochemical genosensor. Our method is applicable to other types of renewable precursors and may open a new avenue for low-cost synthesis of graphene films.

  4. Single-step ambient-air synthesis of graphene from renewable precursors as electrochemical genosensor

    NASA Astrophysics Data System (ADS)

    Seo, Dong Han; Pineda, Shafique; Fang, Jinghua; Gozukara, Yesim; Yick, Samuel; Bendavid, Avi; Lam, Simon Kwai Hung; Murdock, Adrian T.; Murphy, Anthony B.; Han, Zhao Jun; Ostrikov, Kostya (Ken)

    2017-01-01

    Thermal chemical vapour deposition techniques for graphene fabrication, while promising, are thus far limited by resource-consuming and energy-intensive principles. In particular, purified gases and extensive vacuum processing are necessary for creating a highly controlled environment, isolated from ambient air, to enable the growth of graphene films. Here we exploit the ambient-air environment to enable the growth of graphene films, without the need for compressed gases. A renewable natural precursor, soybean oil, is transformed into continuous graphene films, composed of single-to-few layers, in a single step. The enabling parameters for controlled synthesis and tailored properties of the graphene film are discussed, and a mechanism for the ambient-air growth is proposed. Furthermore, the functionality of the graphene is demonstrated through direct utilization as an electrode to realize an effective electrochemical genosensor. Our method is applicable to other types of renewable precursors and may open a new avenue for low-cost synthesis of graphene films.

  5. Single-step ambient-air synthesis of graphene from renewable precursors as electrochemical genosensor

    PubMed Central

    Seo, Dong Han; Pineda, Shafique; Fang, Jinghua; Gozukara, Yesim; Yick, Samuel; Bendavid, Avi; Lam, Simon Kwai Hung; Murdock, Adrian T.; Murphy, Anthony B.; Han, Zhao Jun; Ostrikov, Kostya (Ken)

    2017-01-01

    Thermal chemical vapour deposition techniques for graphene fabrication, while promising, are thus far limited by resource-consuming and energy-intensive principles. In particular, purified gases and extensive vacuum processing are necessary for creating a highly controlled environment, isolated from ambient air, to enable the growth of graphene films. Here we exploit the ambient-air environment to enable the growth of graphene films, without the need for compressed gases. A renewable natural precursor, soybean oil, is transformed into continuous graphene films, composed of single-to-few layers, in a single step. The enabling parameters for controlled synthesis and tailored properties of the graphene film are discussed, and a mechanism for the ambient-air growth is proposed. Furthermore, the functionality of the graphene is demonstrated through direct utilization as an electrode to realize an effective electrochemical genosensor. Our method is applicable to other types of renewable precursors and may open a new avenue for low-cost synthesis of graphene films. PMID:28134336

  6. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    PubMed Central

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

  7. Working characteristics of variable intake valve in compressed air engine.

    PubMed

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

  8. Ambient air quality trends and driving factor analysis in Beijing, 1983-2007.

    PubMed

    Zhang, Ju; Ouyang, Zhiyun; Miao, Hong; Wang, Xiaoke

    2011-01-01

    The rapid development in Beijing, the capital of China, has resulted in serious air pollution problems. Meanwhile great efforts have been made to improve the air quality, especially since 1998. The variation in air quality under the interaction of pollution and control in this mega city has attracted much attention. We analyzed the changes in ambient air quality in Beijing since the 1980's using the Daniel trend test based on data from long-term monitoring stations. The results showed that different pollutants displayed three trends: a decreasing trend, an increasing trend and a flat trend. SO2, dustfall, B[a]P, NO2 and PM10 fit decreasing trend pattern, while NOx showed an increasing trend, and CO, ozone pollution, total suspended particulate (TSP), as well as Pb fit the flat trend. The cause of the general air pollution in Beijing has changed from being predominantly related to coal burning to mixed traffic exhaust and coal burning related pollution. Seasonally, the pollution level is typically higher during the heating season from November to the following March. The interaction between pollution sources change and implementation of air pollution control measures was the main driving factor that caused the variation in air quality. Changes of industrial structure and improved energy efficiency, the use of clean energy and preferred use of clean coal, reduction in pollution sources, and implementation of advanced environmental standards have all contributed to the reduction in air pollution, particularly since 1998.

  9. Twenty years of measurement of polycyclic aromatic hydrocarbons (PAHs) in UK ambient air by nationwide air quality networks.

    PubMed

    Brown, Andrew S; Brown, Richard J C; Coleman, Peter J; Conolly, Christopher; Sweetman, Andrew J; Jones, Kevin C; Butterfield, David M; Sarantaridis, Dimitris; Donovan, Brian J; Roberts, Ian

    2013-06-01

    The impact of human activities on the health of the population and of the wider environment has prompted action to monitor the presence of toxic compounds in the atmosphere. Toxic organic micropollutants (TOMPs) are some of the most insidious and persistent of these pollutants. Since 1991 the United Kingdom has operated nationwide air quality networks to assess the presence of TOMPs, including polycyclic aromatic hydrocarbons (PAHs), in ambient air. The data produced in 2010 marked 20 years of nationwide PAH monitoring. This paper marks this milestone by providing a novel and critical review of the data produced since nationwide monitoring began up to the end of 2011 (the latest year for which published data is available), discussing how the networks performing this monitoring has evolved, and elucidating trends in the concentrations of the PAHs measured. The current challenges in the area and a forward look to the future of air quality monitoring for PAHs are also discussed briefly.

  10. Intraurban Spatiotemporal Variability of Ambient Air Pollutants across Metropolitan St. Louis

    NASA Astrophysics Data System (ADS)

    Du, Li

    Ambient air monitoring networks have been established in the United States since the 1970s to comply with the Clean Air Act. The monitoring networks are primarily used to determine compliance but also provide substantive support to air quality management and air quality research including studies on health effects of air pollutants. The Roxana Air Quality Study (RAQS) was conducted at the fenceline of a petroleum refinery in Roxana, Illinois. In addition to providing insights into air pollutant impacts from the refinery, these measurements increased the St. Louis area monitoring network density for gaseous air toxics and fine particulate matter (PM2.5) speciation and thus provided an opportunity to examine intraurban spatiotemporal variability for these air quality parameters. This dissertation focused on exploring and assessing aspects of ambient air pollutant spatiotemporal variability in the St. Louis area from three progressively expanded spatial scales using a suite of methods and metrics. RAQS data were used to characterize air quality conditions in the immediate vicinity of the petroleum refinery. For example, PM2.5 lanthanoids were used to track impacts from refinery fluidized bed catalytic cracker emissions. RAQS air toxics data were interpreted by comparing to network data from the Blair Street station in the City of St. Louis which is a National Air Toxics Trends Station. Species were classified as being spatially homogeneous (similar between sites) or heterogeneous (different between sites) and in the latter case these differences were interpreted using surface winds data. For PM 2.5 species, there were five concurrently operating sites in the St. Louis area - including the site in Roxana - which are either formally part of the national Chemical Speciation Network (CSN) or rigorously follow the CSN sampling and analytical protocols. This unusually large number of speciation sites for a region the size of St. Louis motivated a detailed examination of

  11. Secondary organic aerosol formation from photo-oxidation of toluene with NOx and SO2: Chamber simulation with purified air versus urban ambient air as matrix

    NASA Astrophysics Data System (ADS)

    Deng, Wei; Liu, Tengyu; Zhang, Yanli; Situ, Shuping; Hu, Qihou; He, Quanfu; Zhang, Zhou; Lü, Sujun; Bi, Xinhui; Wang, Xuemei; Boreave, Antoinette; George, Christian; Ding, Xiang; Wang, Xinming

    2017-02-01

    Chamber studies on the formation of secondary aerosols are mostly performed with purified air as matrix, it is of wide concern in what extent they might be different from the situations in ambient air, where a variety of gaseous and particulate components preexist. Here we compared the photo-oxidation of "toluene + NOx + SO2" combinations in a smog chamber in real urban ambient air matrix with that in purified air matrix. The secondary organic aerosols (SOA) mass concentrations and yields from toluene in the ambient air matrix, after subtracted ambient air background primary and secondary organic aerosols, were 9.0-34.0 and 5.6-12.9 times, respectively, greater than those in purified air matrix. Both homogeneous and heterogeneous oxidation of SO2 were enhanced in ambient air matrix experiments with observed 2.0-7.5 times higher SO2 degradation rates and 2.6-6.8 times faster sulfate formation than that in purified air matrix, resulting in higher in-situ particle acidity and consequently promoting acid-catalyzed SOA formation. In the ambient air experiments although averaged OH radical levels were elevated probably due to heterogeneous formation of OH on particle surface and/or ozonolysis of alkenes, non-OH oxidation pathways of SO2 became even more dominating. Under the same organic aerosol mass concentration, the SOA yields of toluene in purified air matrix experiments matched very well with the two-product model curve by Ng et al. (2007), yet the yields in ambient air on average was over two times larger. The results however were much near the best fit curve by Hildebrandt et al. (2009) with the volatility basis set (VBS) approach.

  12. Amine-Oxide Hybrid Materials for CO2 Capture from Ambient Air.

    PubMed

    Didas, Stephanie A; Choi, Sunho; Chaikittisilp, Watcharop; Jones, Christopher W

    2015-10-20

    Oxide supports functionalized with amine moieties have been used for decades as catalysts and chromatographic media. Owing to the recognized impact of atmospheric CO2 on global climate change, the study of the use of amine-oxide hybrid materials as CO2 sorbents has exploded in the past decade. While the majority of the work has concerned separation of CO2 from dilute mixtures such as flue gas from coal-fired power plants, it has been recognized by us and others that such supported amine materials are also perhaps uniquely suited to extract CO2 from ultradilute gas mixtures, such as ambient air. As unique, low temperature chemisorbents, they can operate under ambient conditions, spontaneously extracting CO2 from ambient air, while being regenerated under mild conditions using heat or the combination of heat and vacuum. This Account describes the evolution of our activities on the design of amine-functionalized silica materials for catalysis to the design, characterization, and utilization of these materials in CO2 separations. New materials developed in our laboratory, such as hyperbranched aminosilica materials, and previously known amine-oxide hybrid compositions, have been extensively studied for CO2 extraction from simulated ambient air (400 ppm of CO2). The role of amine type and structure (molecular, polymeric), support type and structure, the stability of the various compositions under simulated operating conditions, and the nature of the adsorbed CO2 have been investigated in detail. The requirements for an effective, practical air capture process have been outlined and the ability of amine-oxide hybrid materials to meet these needs has been discussed. Ultimately, the practicality of such a "direct air capture" process is predicated not only on the physicochemical properties of the sorbent, but also how the sorbent operates in a practical process that offers a scalable gas-solid contacting strategy. In this regard, the utility of low pressure drop monolith

  13. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... temperature measurement must be made within 122 cm of the engine. The measurement location must be made either... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES...

  14. Health effects of acute exposure to air polllution. Part II: Healthy subjects exposed to cencentrated ambient particles

    EPA Science Inventory

    The purpose of this study was to assess the impact of short-term exposure to concentrated ambient particles (CAPs*) on lung function and on inflammatory parameters in blood and airways of healthy human subjects. Particles were concentrated from the ambient air in Chapel Hill, Nor...

  15. Trends of chlordane and toxaphene in ambient air of Columbia, South Carolina

    NASA Astrophysics Data System (ADS)

    Bidleman, T. F.; Alegria, H.; Ngabe, B.; Green, C.

    A long-term record of chlordane and toxaphene (chlorobornanes, CHBs) measurements in Columbia, South Carolina is presented. Chlordane was used as a termiticide in the city and toxaphene was applied to cotton, soybeans and other crops in the region. Ratios among chlordane compounds in ambient air agreed well with those in technical chlordane when weighted for differences in volatility. Atmospheric concentrations ( Ca, pg m -3) in pre-ban years (1988 for chlordane, 1986 for toxaphene) are compared to those made more recently by normalizing concentrations for the effect of varying ambient temperature. Plots of log C a vs 1/ T suggest that chlordane concentrations at 20°C declined by about 40% between pre-ban years and 1994-1995, but no change is apparent at 5°C. Recent concentrations of CHBs are lower than those measured when toxaphene was in use. Temperature slopes are flatter in post-ban years, possibly because of retarded evaporation of old residues as compared to freshly applied pesticide. The 1994-1995 concentrations of chlordanes and CHBs in Columbia air were several times higher than those found in the Great Lakes region. No distinct trend in CHB levels with air transport direction was noted, suggesting that volatilization from local or regional soils is supplying CHBs to Columbia air.

  16. Proposed Pathophysiologic Framework to Explain Some Excess Cardiovascular Death Associated with Ambient Air Particle Pollution: Insights for Public Health Translation

    EPA Science Inventory

    The paper proposes a pathophysiologic framework to explain the well-established epidemiological association between exposure to ambient air particle pollution and premature cardiovascular mortality, and offers insights into public health solutions that extend beyond regularory en...

  17. 40 CFR Appendix N to Part 50 - Interpretation of the National Ambient Air Quality Standards for PM2.5

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... 50, App. N Appendix N to Part 50—Interpretation of the National Ambient Air Quality Standards for PM2... accordance with part 58 of this chapter. Design values are the metrics (i.e., statistics) that are...

  18. Ambient Air Quality Assessment with Particular Reference to Particulates in Jharia Coalfield, Eastern India.

    PubMed

    Singh, Gurdeep; Roy, Debananda; Sinha, Sweta

    2014-01-01

    Jharia Coalfield is the critically polluted area with the intense mining and associated industrial activities. There has been widespread concern of particulate pollution with the alarming levels of Suspended Particulate Matter (SPM) and Respirable Particulate Matter (PM10 & PM2.5). Coke oven plants, coal washing, thermal power stations and associated activities coupled with the transportation activities, give rise to critical air pollution levels in the region. This study envisages the assessment of air pollution of the region with particular reference to SPM, PM10 and PM2.5. Eighteen monitoring stations were selected considering various sources of pollution such as mining, industrial, commercial and residential areas apart from siting criteria as per IS: 5182 Part XIV. Air quality monitoring was carried out following standard methodologies and protocols as per Central Pollution Control Board (CPCB)/ National Ambient Air Quality Standard (NAAQS) norms using Respirable Dust Samplers (RDS) and Fine Particulate Samplers (PM2.5 Samplers). This study reveals considerable load of particulates (SPM, PM10, PM 2.5) which exceed not only the NAAQS but also the coal mining areas standards of Jharia coalfield, thus falling under the category of critically polluted area. Air Quality Indexing has also been developed which provides a clear map of the deterioration of air quality and also presenting comparative ranking of all the monitoring locations with respect to air quality status in the study area.

  19. ENGINEERING BULLETIN: AIR STRIPPING OF AQUEOUS SOLUTIONS

    EPA Science Inventory

    Air striding is a means to transfer contaminants from aqueous solutions to air. ontaminants are not destroyed by air stripping but are physically separated from the aqueous solutions. ontaminant vapors are transferred into the air stream and, if necessary, can be treated by incin...

  20. Personal and Ambient Air Pollution Exposures and Lung Function Decrements in Children with Asthma

    PubMed Central

    Delfino, Ralph J.; Staimer, Norbert; Tjoa, Thomas; Gillen, Dan; Kleinman, Michael T.; Sioutas, Constantinos; Cooper, Dan

    2008-01-01

    Background Epidemiologic studies have shown associations between asthma outcomes and outdoor air pollutants such as nitrogen dioxide and particulate matter mass < 2.5 μm in diameter (PM2.5). Independent effects of specific pollutants have been difficult to detect because most studies have relied on highly correlated central-site measurements. Objectives This study was designed to evaluate the relationship of daily changes in percent-predicted forced expiratory volume in 1 sec (FEV1) with personal and ambient air pollutant exposures. Methods For 10 days each, we followed 53 subjects with asthma who were 9–18 years of age and living in the Los Angeles, California, air basin. Subjects self-administered home spirometry in themorning, afternoon, and evening. We measured personal hourly PM2.5 mass, 24-hr PM2.5 elemental and organic carbon (EC–OC), and 24-hr NO2, and the same 24-hr average outdoor central-site(ambient) exposures. We analyzed data with transitional mixed models controlling for personal temperature and humidity, and as-needed β2-agonist inhaler use. Results FEV1 decrements were significantly associated with increasing hourly peak and daily average personal PM2.5, but not ambient PM2.5. Personal NO2 was also inversely associated with FEV1. Ambient NO2 was more weakly associated. We found stronger associations among 37 subjects not taking controller bronchodilators as follows: Personal EC–OC was inversely associated with morning FEV1; for an interquartile increase of 71 μg/m3 1-hr maximum personal PM2.5, overall percent-predicted FEV1 decreased by 1.32% [95% confidence interval (CI), −2.00 to −0.65%]; and for an interquartile increase of 16.8 ppb 2-day average personal NO2, overall percent-predicted FEV1 decreased by 2.45% (95% CI, −3.57 to −1.33%). Associations of both personal PM2.5 and NO2 with FEV1 remained when co-regressed, and both confounded ambient NO2. Conclusions Independent pollutant associations with lung function might be missed

  1. Assessing uncertain human exposure to ambient air pollution using environmental models in the Web

    NASA Astrophysics Data System (ADS)

    Gerharz, L. E.; Pebesma, E.; Denby, B.

    2012-04-01

    Ambient air quality can have significant impact on human health by causing respiratory and cardio-vascular diseases. Thereby, the pollutant concentration a person is exposed to can differ considerably between individuals depending on their daily routine and movement patterns. Using a straight forward approach this exposure can be estimated by integration of individual space-time paths and spatio-temporally resolved ambient air quality data. To allow a realistic exposure assessment, it is furthermore important to consider uncertainties due to input and model errors. In this work, we present a generic, web-based approach for estimating individual exposure by integration of uncertain position and air quality information implemented as a web service. Following the Model Web initiative envisioning an infrastructure for deploying, executing and chaining environmental models as services, existing models and data sources for e.g. air quality, can be used to assess exposure. Therefore, the service needs to deal with different formats, resolutions and uncertainty representations provided by model or data services. Potential mismatch can be accounted for by transformation of uncertainties and (dis-)aggregation of data under consideration of changes in the uncertainties using components developed in the UncertWeb project. In UncertWeb, the Model Web vision is extended to an Uncertainty-enabled Model Web, where services can process and communicate uncertainties in the data and models. The propagation of uncertainty to the exposure results is quantified using Monte Carlo simulation by combining different realisations of positions and ambient concentrations. Two case studies were used to evaluate the developed exposure assessment service. In a first study, GPS tracks with a positional uncertainty of a few meters, collected in the urban area of Münster, Germany were used to assess exposure to PM10 (particulate matter smaller 10 µm). Air quality data was provided by an

  2. Removal of polycyclic aromatic hydrocarbons (PAHs) from industrial sludges in the ambient air conditions: automotive industry.

    PubMed

    Karaca, Gizem; Tasdemir, Yucel

    2013-01-01

    Removal of polycyclic aromatic hydrocarbons (PAHs) existed in automotive industry treatment sludge was examined by considering the effects of temperature, UV, titanium dioxide (TiO2) and diethyl amine (DEA) in different dosages (i.e., 5% and 20%) in this study. Application of TiO2 and DEA to the sludge samples in ambient environment was studied. Ten PAH (Σ10 PAH) compounds were targeted and their average value in the sludge was found to be 4480 ± 1450 ng/g dry matter (DM). Total PAH content of the sludge was reduced by 25% in the ambient air environment. Meteorological conditions, atmospheric deposition, evaporation and sunlight irradiation played an effective role in the variations in PAH levels during the tests carried out in ambient air environment. Moreover, it was observed that when the ring numbers of PAHs increased, their removal rates also increased. Total PAH level did not change with the addition of 5% DEA and only 10% decreased with 5% TiO2 addition. PAH removal ratios were 8% and 32% when DEA (20%) and TiO2 (20%) were added, respectively. It was concluded that DEA was a weak photo-sensitizer yet TiO2 was effective only at 20% dosage.

  3. Declining ambient air pollution and lung function improvement in Austrian children

    NASA Astrophysics Data System (ADS)

    Neuberger, Manfred; Moshammer, Hanns; Kundi, Michael

    Three thousand four hundred fifty-one Austrian elementary school children were examined (between 2 and 8 times) by spirometry by standardized methods, over a 5 yr period. The districts where they lived were grouped into those where NO 2 declined during this period (by at least 30 μg/m 3 measured as half year means) and those with less or no decline in ambient NO 2. In both groups of districts, SO 2 and TSP fell by similar amounts over this period. A continuous improvement of MEF25 (maximum exspiratory flow rate at 25% vital capacity) was found in districts with declining ambient NO 2. Populations did not differ in respect of anthropometric factors, passive smoking or socioeconomic status. A birth cohort from this study population which was followed up to age 18 confirmed the improved growth of MEF25 with decline in NO 2, while the improved growth of forced vital capacity was more related to decline in SO 2. This study provides the first evidence that improvements in the outdoor air quality during the 1980s are correlated with health benefits, and suggest that adverse effects on lung function related to ambient air pollution are reversible before adulthood. Improvement of small airway functions appeared to be more dependent on reductions of NO 2 than reduction in SO 2 and TSP.

  4. A metrological approach to improve accuracy and reliability of ammonia measurements in ambient air

    NASA Astrophysics Data System (ADS)

    Pogány, Andrea; Balslev-Harder, David; Braban, Christine F.; Cassidy, Nathan; Ebert, Volker; Ferracci, Valerio; Hieta, Tuomas; Leuenberger, Daiana; Martin, Nicholas A.; Pascale, Céline; Peltola, Jari; Persijn, Stefan; Tiebe, Carlo; Twigg, Marsailidh M.; Vaittinen, Olavi; van Wijk, Janneke; Wirtz, Klaus; Niederhauser, Bernhard

    2016-11-01

    The environmental impacts of ammonia (NH3) in ambient air have become more evident in the recent decades, leading to intensifying research in this field. A number of novel analytical techniques and monitoring instruments have been developed, and the quality and availability of reference gas mixtures used for the calibration of measuring instruments has also increased significantly. However, recent inter-comparison measurements show significant discrepancies, indicating that the majority of the newly developed devices and reference materials require further thorough validation. There is a clear need for more intensive metrological research focusing on quality assurance, intercomparability and validations. MetNH3 (Metrology for ammonia in ambient air) is a three-year project within the framework of the European Metrology Research Programme (EMRP), which aims to bring metrological traceability to ambient ammonia measurements in the 0.5-500 nmol mol-1 amount fraction range. This is addressed by working in three areas: (1) improving accuracy and stability of static and dynamic reference gas mixtures, (2) developing an optical transfer standard and (3) establishing the link between high-accuracy metrological standards and field measurements. In this article we describe the concept, aims and first results of the project.

  5. Ambient Air Pollution and Depressive Symptoms in Older Adults: Results from the MOBILIZE Boston Study

    PubMed Central

    Wang, Yi; Eliot, Melissa N.; Koutrakis, Petros; Gryparis, Alexandros; Schwartz, Joel D.; Coull, Brent A.; Mittleman, Murray A.; Milberg, William P.; Lipsitz, Lewis A.

    2014-01-01

    Background: Exposure to ambient air pollution, particularly from traffic, has been associated with adverse cognitive outcomes, but the association with depressive symptoms remains unclear. Objectives: We investigated the association between exposure to ambient air and traffic pollution and the presence of depressive symptoms among 732 Boston-area adults ≥ 65 years of age (78.1 ± 5.5 years, mean ± SD). Methods: We assessed depressive symptoms during home interviews using the Revised Center for Epidemiological Studies Depression Scale (CESD-R). We estimated residential distance to the nearest major roadway as a marker of long-term exposure to traffic pollution and assessed short-term exposure to ambient fine particulate matter (PM2.5), sulfates, black carbon (BC), ultrafine particles, and gaseous pollutants, averaged over the 2 weeks preceding each assessment. We used generalized estimating equations to estimate the odds ratio (OR) of a CESD-R score ≥ 16 associated with exposure, adjusting for potential confounders. In sensitivity analyses, we considered CESD-R score as a continuous outcome and mean annual residential BC as an alternate marker of long-term exposure to traffic pollution. Results: We found no evidence of a positive association between depressive symptoms and long-term exposure to traffic pollution or short-term changes in pollutant levels. For example, we found an OR of CESD-R score ≥ 16 of 0.67 (95% CI: 0.46, 0.98) per interquartile range (3.4 μg/m3) increase in PM2.5 over the 2 weeks preceding assessment. Conclusions: We found no evidence suggesting that ambient air pollution is associated with depressive symptoms among older adults living in a metropolitan area in attainment of current U.S. regulatory standards. Citation: Wang Y, Eliot MN, Koutrakis P, Gryparis A, Schwartz JD, Coull BA, Mittleman MA, Milberg WP, Lipsitz LA, Wellenius GA. 2014. Ambient air pollution and depressive symptoms in older adults: results from the MOBILIZE Boston

  6. Introduction of correlative light and airSEMTM microscopy imaging for tissue research under ambient conditions

    PubMed Central

    Solomonov, Inna; Talmi-Frank, Dalit; Milstein, Yonat; Addadi, Sefi; Aloshin, Anna; Sagi, Irit

    2014-01-01

    A complete fingerprint of a tissue sample requires a detailed description of its cellular and extracellular components while minimizing artifacts. We introduce the application of a novel scanning electron microscope (airSEMTM) in conjunction with light microscopy for functional analysis of tissue preparations at nanometric resolution (<10 nm) and under ambient conditions. Our metal-staining protocols enable easy and detailed visualization of tissues and their extracellular scaffolds. A multimodality imaging setup, featuring airSEMTM and a light microscope on the same platform, provides a convenient and easy-to-use system for obtaining structural and functional correlative data. The airSEMTM imaging station complements other existing imaging solutions and shows great potential for studies of complex biological systems. PMID:25100357

  7. Quantification Method for Electrolytic Sensors in Long-Term Monitoring of Ambient Air Quality.

    PubMed

    Masson, Nicholas; Piedrahita, Ricardo; Hannigan, Michael

    2015-10-27

    Traditional air quality monitoring relies on point measurements from a small number of high-end devices. The recent growth in low-cost air sensing technology stands to revolutionize the way in which air quality data are collected and utilized. While several technologies have emerged in the field of low-cost monitoring, all suffer from similar challenges in data quality. One technology that shows particular promise is that of electrolytic (also known as amperometric) sensors. These sensors produce an electric current in response to target pollutants. This work addresses the development of practical models for understanding and quantifying the signal response of electrolytic sensors. Such models compensate for confounding effects on the sensor response, such as ambient temperature and humidity, and address other issues that affect the usability of low-cost sensors, such as sensor drift and inter-sensor variability.

  8. Preliminary assessment of worker and ambient air exposures during soil remediation technology demonstration.

    PubMed

    Romine, James D; Barth, Edwin F

    2002-01-01

    Hazardous waste site remediation workers or neighboring residents may be exposed to particulates during the remediation of lead-contaminated soil sites. Industrial hygiene surveys and air monitoring programs for both lead and dust were performed during initial soil sampling activities and during pilot scale technology demonstration activities at two lead-contaminated soil sites to assess whether worker protection or temporary resident relocation would be suggested during any subsequent remediation technology activities. The concentrations of lead and dust in the air during pilot scale technology demonstration studies were within applicable exposure guidelines, including Occupational Health and Safety Administration permissible exposure limits, National Institute for Occupational Safety and Health recommended exposure limits, American Conference of Governmental Industrial Hygiene threshold limit values, and the United States Environmental Protection Agency's National Ambient Air Quality Standards program limits.

  9. Carcinogenicity of ambient air pollution: use of biomarkers, lessons learnt and future directions

    PubMed Central

    Vineis, Paolo

    2015-01-01

    The association between ambient air pollution (AAP) exposure and lung cancer risk has been investigated in prospective studies and the results are generally consistent, indicating that long-term exposure to air pollution can cause lung cancer. Biomarkers can enhance research on the health effects of air pollution by improving exposure assessment, increasing the understanding of mechanisms, and enabling the investigation of individual susceptibility. In this review, we assess DNA adducts as biomarkers of exposure to AAP and early biological effect, and DNA methylation as biomarker of early biological change and discuss critical issues arising from their incorporation in AAP health impact evaluations, such as confounding, individual susceptibilities, timing, intensity and duration of exposure, and investigated tissue. DNA adducts and DNA methylation are treated as paradigms. However, the lessons, learned from their use in the examination of AAP carcinogenicity, can be applied to investigations of other biomarkers involved in AAP carcinogenicity. PMID:25694819

  10. Quantification Method for Electrolytic Sensors in Long-Term Monitoring of Ambient Air Quality

    PubMed Central

    Masson, Nicholas; Piedrahita, Ricardo; Hannigan, Michael

    2015-01-01

    Traditional air quality monitoring relies on point measurements from a small number of high-end devices. The recent growth in low-cost air sensing technology stands to revolutionize the way in which air quality data are collected and utilized. While several technologies have emerged in the field of low-cost monitoring, all suffer from similar challenges in data quality. One technology that shows particular promise is that of electrolytic (also known as amperometric) sensors. These sensors produce an electric current in response to target pollutants. This work addresses the development of practical models for understanding and quantifying the signal response of electrolytic sensors. Such models compensate for confounding effects on the sensor response, such as ambient temperature and humidity, and address other issues that affect the usability of low-cost sensors, such as sensor drift and inter-sensor variability. PMID:26516860

  11. Emissions and ambient air monitoring trends of lower olefins across Texas from 2002 to 2012.

    PubMed

    Myers, Jessica L; Phillips, Tracie; Grant, Roberta L

    2015-11-05

    Texas has the largest ambient air monitoring network in the country with approximately 83 monitoring sites that measure ambient air concentrations of volatile organic compounds (VOCs). The lower olefins, including 1,3-butadiene, ethylene, isoprene, and propylene, are a group of VOCs that can be measured in both 24h/every sixth-day canister samples and continuous 1-h Automated Gas Chromatography (AutoGC) samples. Based on 2012 Toxics Release Inventory data, the total reported industrial air emissions in Texas for these olefins, as compared to total national reported air emissions, were 79% for 1,3-butadiene, 62% for ethylene, 76% for isoprene, and 54% for propylene, illustrating that Texas industries are some of the major emitters for these olefins. The purpose of this study was to look at the patterns of annual average air monitoring data from 2002 to 2012 using Texas Commission on Environmental Quality (TCEQ) data for these four lower olefins. It should be emphasized that monitors may not be located close to or downwind of the highest emitters of these lower olefins. In addition, air monitors only provide a snapshot in time of air concentrations for their respective locations, and may not be able to discriminate emissions between specific sources. In 2012, the highest annual average air concentration for 1,3-butadiene was 1.28 ppb by volume (ppbv), which was measured at the Port Neches monitoring site in Region 10-Beaumont. For ethylene, the highest 2012 annual average air concentration was 5.77 ppbv, which was measured at the Dona Park monitoring site in TCEQ Region 14-Corpus Christi. Although reported industrial emissions of isoprene are predominantly from the Houston and Beaumont regions, trees are natural emitters of isoprene, and the highest ambient air concentrations tend to be from regions with large areas of coniferous and hardwood forests. This was observed with TCEQ Region 5-Tyler, which had the two highest isoprene annual average air concentrations for

  12. Influence of chemical and physical forms of ambient air acids on airway doses

    SciTech Connect

    Larson, T.V.

    1989-02-01

    The effects of ambient relative humidity and particle size on acid deposition within the airways have been examined with a computer model. For H/sub 2/SO/sub 4/ particles initially at 90% relative humidity in ambient air that are inhaled via the nose or mouth, there is significant deposition of acid in the airways even in the presence of typical values of respiratory NH/sub 3/. When these same particles are found in a fog at 100.015% relative humidity, there is significant deposition of acid in the nasal region during nose breathing but insignificant deposition to the deep lung for either nose or mouth breathing. The factors governing the partitioning of labile acid gases in the gas and liquid phases prior to inhalation are also discussed.

  13. Ambient air pollution exposure and the incidence of related health effects among racial/ethnic minorities

    SciTech Connect

    Nieves, L.A.; Wernette, D.R.

    1997-02-01

    Differences among racial and ethnic groups in morbidity and mortality rates for diseases, including diseases with environmental causes, have been extensively documented. However, documenting the linkages between environmental contaminants, individual exposures, and disease incidence has been hindered by difficulties in measuring exposure for the population in general and for minority populations in particular. After briefly discussing research findings on associations of common air pollutants with disease incidence, the authors summarize recent studies of radial/ethnic subgroup differences in incidence of these diseases in the US. They then present evidence of both historic and current patterns of disproportionate minority group exposure to air pollution as measured by residence in areas where ambient air quality standards are violated. The current indications of disproportionate potential exposures of minority and low-income populations to air pollutants represent the continuation of a historical trend. The evidence of linkage between disproportionate exposure to air pollution of racial/ethnic minorities and low-income groups and their higher rates of some air pollution-related diseases is largely circumstantial. Differences in disease incidence and mortality rates among racial/ethnic groups are discussed for respiratory diseases, cancers, and lead poisoning. Pollutants of concern include CO, Pb, SO{sub 2}, O{sub 3}, and particulates.

  14. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study

    PubMed Central

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-01-01

    Allergic conjunctivitis is a common problem that significantly impairs patients’ quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis. PMID:27033635

  15. Industrial CO2 Removal: CO2 Capture from Ambient Air and Geological Sequestration

    SciTech Connect

    Dooley, James J.

    2011-06-08

    This abstract and its accompanying presentation will provide an overview of two distinct industrial processes for removing carbon dioxide (CO2) from the atmosphere as a means of addressing anthropogenic climate change. The first of these is carbon dioxide capture and storage (CCS) coupled with large scale biomass production (hereafter referred to as bioCCS). The second is CO2 capture from ambient air via industrial systems (hereafter referred to as direct air capture (DAC)). In both systems, the captured CO2 would be injected into deep geologic formations so as to isolate it from the atmosphere. The technical literature is clear that both of these technologies are technically feasible as of today (IPCC, 2005; Keith, 2009; Lackner, 2009; Luckow et al., 2010; Ranjan and Herzog, 2011). What is uncertain is the relative cost of these industrial ambient-air CO2 removal systems when compared to other emissions mitigation measures, the ultimate timing and scale of their deployment, and the resolution of potential site specific constraints that would impact their ultimate commercial deployment.

  16. Recognizing the Challenges of Ambient Air Monitoring in the Persian Gulf

    NASA Astrophysics Data System (ADS)

    Meade, T. G.; Nicodemus, M. A.; Howard, J. M.

    2011-12-01

    In an effort to better estimate environmental exposure, the U.S. Army Public Health Command has been operating an ambient air monitoring station in Shuaiba Port, Kuwait since 2002. The focus has primarily been on monitoring criteria pollutants at a busy sea port where local industry (oil refineries, cement plant, petrochemical production, etc.) heavily impacts air quality. To compound the issues associated with day to day monitoring at a busy sea port, the region often experiences sand storms and temperatures up to 60°C. Average daily particulate matter concentrations at Shuaiba Port are an order of magnitude higher than similar industrial areas in the U.S. On days when sand storms occur ambient PM concentrations can be two or three orders higher than average daily U.S. concentrations. For example, 24-hour average PM10 concentrations from 2004-2010 for the month of June were 395 μg/m3. During sand storms, 24-hour average concentrations can reach as high as 4,000 μg/m3. This poster presents 2004-2010 particulate matter data collected at Shuaiba Port, Kuwait and outlines logistical and environmental challenges associated with air monitoring in the region.

  17. Ambient air pollution and lung disease in China: health effects, study design approaches and future research.

    PubMed

    Mandel, Jeffrey H; Wendt, Christine; Lo, Charles; Zhou, Guangbiao; Hertz, Marshall; Ramachandran, Gurumurthy

    2015-09-01

    Ambient air pollution in China has worsened following dramatic increases in industrialization, automobile use and energy consumption. Particularly bothersome is the increase in the PM2.5 fraction of pollutants. This fraction has been associated with increasing rates of cardio-respiratory disease in China and elsewhere. Ambient pollutant levels have been described in many of China's cities and are comparable to previous levels in southern California. Lung cancer mortality in China has increased since the 1970s and has been higher in men and in urban areas, the exact explanation for which has not been determined. The estimation of individual risk for Chinese citizens living in areas of air pollution will require further research. Occupational cohort and case-control designs each have unique attributes that could make them helpful to use in this setting. Other important future research considerations include detailed exposure assessment and the possible use of biomarkers as a means to better understand and manage the threat posed by air pollution in China.

  18. Metallurgically lithiated SiOx anode with high capacity and ambient air compatibility

    PubMed Central

    Zhao, Jie; Lee, Hyun-Wook; Sun, Jie; Yan, Kai; Liu, Yayuan; Liu, Wei; Lu, Zhenda; Lin, Dingchang; Zhou, Guangmin; Cui, Yi

    2016-01-01

    A common issue plaguing battery anodes is the large consumption of lithium in the initial cycle as a result of the formation of a solid electrolyte interphase followed by gradual loss in subsequent cycles. It presents a need for prelithiation to compensate for the loss. However, anode prelithiation faces the challenge of high chemical reactivity because of the low anode potential. Previous efforts have produced prelithiated Si nanoparticles with dry air stability, which cannot be stabilized under ambient air. Here, we developed a one-pot metallurgical process to synthesize LixSi/Li2O composites by using low-cost SiO or SiO2 as the starting material. The resulting composites consist of homogeneously dispersed LixSi nanodomains embedded in a highly crystalline Li2O matrix, providing the composite excellent stability even in ambient air with 40% relative humidity. The composites are readily mixed with various anode materials to achieve high first cycle Coulombic efficiency (CE) of >100% or serve as an excellent anode material by itself with stable cyclability and consistently high CEs (99.81% at the seventh cycle and ∼99.87% for subsequent cycles). Therefore, LixSi/Li2O composites achieved balanced reactivity and stability, promising a significant boost to lithium ion batteries. PMID:27313206

  19. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study.

    PubMed

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-04-01

    Allergic conjunctivitis is a common problem that significantly impairs patients' quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis.

  20. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study

    NASA Astrophysics Data System (ADS)

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-04-01

    Allergic conjunctivitis is a common problem that significantly impairs patients’ quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis.

  1. Impact of a new gasoline benzene regulation on ambient air pollutants in Anchorage, Alaska

    NASA Astrophysics Data System (ADS)

    Yano, Yuriko; Morris, Stephen S.; Salerno, Christopher; Schlapia, Anne M.; Stichick, Mathew

    2016-05-01

    The purpose of this study was to quantify the impact of a new U.S. Environmental Protection Agency (EPA) standard that limits the amount of benzene allowed in gasoline on ambient benzene concentrations. This new standard, together with two companion regulations that limit cold-temperature automotive emissions and the permeability of portable fuel containers, was expected to lower the levels of ambient benzene and other volatile organic compounds (VOCs) nationwide. In this study the impact of the gasoline benzene standard was evaluated in Anchorage, Alaska in a two-phase ambient air monitoring study conducted before and after the new gasoline standard was implemented. Gasoline sold by Anchorage retailers was also evaluated in each phase to determine the content of benzene and other gasoline components. The average benzene content in Anchorage gasoline was reduced by 70%, from 5.05% (w/w) to 1.53% (w/w) following the implementation of the standard. The annual mean ambient benzene concentration fell by 51%, from 0.99 ppbv in Phase 1 to 0.49 ppbv in Phase 2. Analysis suggests the change in gasoline benzene content alone reduced benzene emissions by 46%. The changes in toluene, ethylbenzene, and xylene content in gasoline between Phase 1 and 2 were relatively small and the differences in the mean ambient concentrations of these compounds between phases were modest. Our results suggest that cold winter communities in high latitude and mountainous regions may benefit more from the gasoline benzene standard because of high benzene emissions resulting from vehicle cold start and a tendency to develop atmospheric stagnation conditions in the winter.

  2. Short-term respiratory effects of polluted ambient air: a laboratory study of volunteers in a high-oxidant community

    SciTech Connect

    Linn, W.S.; Jones, M.P.; Bachmayer, E.A.; Spier, C.E.; Mazur, S.F.; Avol, E.L.; Hackney, J.D.

    1980-02-01

    To investigate short-term health effects of community air pollution directly, researchers developed a mobile laboratory allowing blind exposures of volunteers to polluted ambient air and to purified air at similar temperature and humidity. Subjects from the surrounding area were studied at Duarte, California, a Los Angeles suburb subject to frequent photochemical oxidant pollution. Each was exposed to a close approximation of outdoor ambient air for 2 h with intermittent light exercise. Lung function and symptoms were evaluated pre- and post-exposure. A control study took place several weeks later. Mean ambient air exposure concentrations were near 0.22 ppM for ozone and 200 micrograms/m3 for total suspended particulate. Ambient air exposures were associated with small significant losses in forced expiratory performance and total lung capacity. The responses of asthmatic and normal subjects were generally not significantly different, possibly because many normal subjects had a history of allergy and appeared atypically reactive to respiratory insults. In the normal subjects, a small significant increase in reported symptoms was seen with ambient air exposures compared with the control. In the asthmatics, the increase was not significant. Over-all, only slight effects attributable to exposure were found, even though a severely polluted area and a presumed high-risk population were chosen for study.

  3. A Study of Air Flow in an Engine Cylinder

    NASA Technical Reports Server (NTRS)

    Lee, Dana W

    1939-01-01

    A 4-stroke-cycle test engine was equipped with a glass cylinder and the air movements within it were studied while the engine was being motored. Different types of air flow were produced by using shrouded intake valves in various arrangements and by altering the shape of the intake-air passage in the cylinder head. The air movements were made visible by mixing feathers with the entering air, and high-speed motion pictures were taken of them so that the air currents might be studied in detail and their velocities measured. Motion pictures were also taken of gasoline sprays injected into the cylinder on the intake stroke. The photographs showed that: a wide variety of induced air movements could be created in the cylinder; the movements always persisted throughout the compression stroke; and the only type of movement that persisted until the end of the cycle was rotation about the cylinder axis.

  4. Artificial intelligence modeling to evaluate field performance of photocatalytic asphalt pavement for ambient air purification.

    PubMed

    Asadi, Somayeh; Hassan, Marwa; Nadiri, Ataallah; Dylla, Heather

    2014-01-01

    In recent years, the application of titanium dioxide (TiO₂) as a photocatalyst in asphalt pavement has received considerable attention for purifying ambient air from traffic-emitted pollutants via photocatalytic processes. In order to control the increasing deterioration of ambient air quality, urgent and proper risk assessment tools are deemed necessary. However, in practice, monitoring all process parameters for various operating conditions is difficult due to the complex and non-linear nature of air pollution-based problems. Therefore, the development of models to predict air pollutant concentrations is very useful because it can provide early warnings to the population and also reduce the number of measuring sites. This study used artificial neural network (ANN) and neuro-fuzzy (NF) models to predict NOx concentration in the air as a function of traffic count (Tr) and climatic conditions including humidity (H), temperature (T), solar radiation (S), and wind speed (W) before and after the application of TiO₂ on the pavement surface. These models are useful for modeling because of their ability to be trained using historical data and because of their capability for modeling highly non-linear relationships. To build these models, data were collected from a field study where an aqueous nano TiO₂ solution was sprayed on a 0.2-mile of asphalt pavement in Baton Rouge, LA. Results of this study showed that the NF model provided a better fitting to NOx measurements than the ANN model in the training, validation, and test steps. Results of a parametric study indicated that traffic level, relative humidity, and solar radiation had the most influence on photocatalytic efficiency.

  5. Risk of leukemia in relation to exposure to ambient air toxics in pregnancy and early childhood

    PubMed Central

    Heck, Julia E; Park, Andrew S; Qiu, Jiaheng; Cockburn, Myles; Ritz, Beate

    2014-01-01

    There are few established causes of leukemia, the most common type of cancer in children. Studies in adults suggest a role for specific environmental agents, but little is known about any effect from exposures in pregnancy to toxics in ambient air. In our case-control study, we ascertained 69 cases of acute lymphoblastic leukemia (ALL) and 46 cases of acute myeloid leukemia (AML) from California Cancer Registry records of children < age 6, and 19,209 controls from California birth records within 2km (1.3 miles) (ALL) and 6km (3.8 miles) (AML) of an air toxics monitoring station between 1990–2007. Information on air toxics exposures was taken from community air monitors. We used logistic regression to estimate the risk of leukemia associated with one interquartile range increase in air toxic exposure. Risk of ALL was elevated with 3rd trimester exposure to polycyclic aromatic hydrocarbons (OR=1.16, 95%CI 1.04, 1.29), arsenic (OR=1.33, 95%CI 1.02, 1.73), benzene (OR=1.50, 95%CI 1.08, 2.09), and three other toxics related to fuel combustion. Risk of AML was increased with 3rd trimester exposure to chloroform (OR=1.30, 95%CI 1.00, 1.69), benzene (1.75, 95%CI 1.04, 2.93), and two other traffic-related toxics. During the child’s first year, exposure to butadiene, ortho-xylene, and toluene increased risk for AML and exposure to selenium increased risk for ALL. Benzene is an established cause of leukemia in adults; this study supports that ambient exposures to this and other chemicals in pregnancy and early life may also increase leukemia risk in children. PMID:24472648

  6. Heat-transfer processes in air-cooled engine cylinders

    NASA Technical Reports Server (NTRS)

    Pinkel, Benjamin

    1938-01-01

    From a consideration of heat-transfer theory, semi-empirical expressions are set up for the transfer of heat from the combustion gases to the cylinder of an air-cooled engine and from the cylinder to the cooling air. Simple equations for the average head and barrel temperatures as functions of the important engine and cooling variables are obtained from these expressions. The expressions involve a few empirical constants, which may be readily determined from engine tests. Numerical values for these constants were obtained from single-cylinder engine tests for cylinders of the Pratt & Whitney 1535 and 1340-h engines. The equations provide a means of calculating the effect of the various engine and cooling variables on the cylinder temperatures and also of correlating the results of engine cooling tests. An example is given of the application of the equations to the correlation of cooling-test data obtained in flight.

  7. Ambient air pollution and term birth weight in Texas from 1998 to 2004.

    PubMed

    Geer, Laura A; Weedon, Jeremy; Bell, Michelle L

    2012-11-01

    Previous studies have explored the association between air pollution levels and adverse birth outcomes such as lower birth weight. Existing literature suggests an association, although results across studies are not consistent. Additional research is needed to confirm the effect, investigate the exposure window of importance, and distinguish which pollutants cause harm. We assessed the association between ambient pollutant concentrations and term birth weight for 1,548,904 births in TX from 1998 to 2004. Assignment of prenatal exposure to air pollutants was based on maternal county of residence at the time of delivery. Pollutants examined included particulate matter with aerodynamic diameter < or = 10 and < or = 2.5 microm (PM10 and PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3). We applied a linear model with birth weight as a continuous variable. The model was adjusted for known risk factors and region. We assessed pollutant effects by trimester to identify biological exposure window of concern, and explored interaction due to race/ethnicity. An interquartile increase in ambient pollutant concentrations of SO2 and O3 was associated with a 4.99-g (95% confidence interval [CI], 1.87-8.11) and 2. 72-g (95% CI, 1.11-4.33) decrease in birth weight, respectively. Lower birth weight was associated with exposure to O3 in the first and second trimester; whereas results were not significant for other pollutants by trimester A positive association was exhibited for PM2.5 in the first trimester. Effects estimates for PM10 and PM2.5 were inconsistent across race/ethnic groups. Current ambient air pollution levels may be increasing the risk of lower birth weight for some pollutants. These risks may be increased for certain racial/ethnic groups. Additional research including consideration of improved methodology is needed to investigate these findings. Future studies should examine the influence of residual confounding.

  8. Ambient air pollution exposure, residential mobility and term birth weight in Oslo, Norway.

    PubMed

    Madsen, Christian; Gehring, Ulrike; Walker, Sam Erik; Brunekreef, Bert; Stigum, Hein; Naess, Oyvind; Nafstad, Per

    2010-05-01

    Environmental exposure during pregnancy may have lifelong health consequences for the offspring and some studies have association between maternal exposure to air pollution during pregnancy and offspring's birth weight. However, many of these studies do not take into account small-scale variations in exposure, residential mobility, and work addresses during pregnancy. We used information from the National Birth Registry of Norway to examine associations between ambient environmental exposure such as air pollution and temperature, and offspring's birth weight taking advantage of information on migration history and work address in a large population-based cohort. A dispersion model was used to estimate ambient air pollution levels at all residential addresses and work addresses for a total of 25,229 pregnancies between 1999 and 2002 in Oslo, Norway. Ambient exposure to traffic pollution for the entire pregnancy was associated with a reduction in term birth weight in crude analyzes when comparing children of the highest and lowest exposed mothers. No evidence for an association between exposure to traffic pollution at home and work addresses and term birth weight after adjustment for covariates known to influence birth weight during pregnancy. After stratification, small statistically non-significant reductions were present but only for multiparious mothers. This group also had less residential mobility and less employment during pregnancy. The overall findings suggest no clear association between term birth weight and traffic pollution exposure during pregnancy. However, mobility patterns could introduce possible confounding when examining small-scale variations in exposure by using addresses. This could be of importance in future studies.

  9. Volcanic gas emissions and their impact on ambient air character at Kilauea Volcano, Hawaii

    SciTech Connect

    Sutton, A.J.; Elias, T.; Navarrete, R.

    1994-12-31

    Gas emissions from Kilauea occur from the summit caldera, along the middle East Rift Zone (ERZ), and where lava enters the ocean. We estimate that the current ERZ eruption of Kilauea releases between 400 metric tonnes of SO{sub 2} per day, during eruptive pauses, to as much as 1850 metric tonnes per day during actively erupting periods, along with lesser amounts of other chemically and radiatively active species including H{sub 2}S, HCl and HF. In order to characterize gas emissions from Kilauea in a meaningful way for assessing environmental impact, we made a series of replicate grab-sample measurements of ambient air and precipitation at the summit of Kilauea, along its ERZ, and at coastal sites where lava enters the ocean. The grab-sampling data combined with SO{sub 2} emission rates, and continuous air quality and meteorological monitoring at the summit of Kilauea show that the effects of these emissions on ambient air character are a complex function of chemical reactivity, source geometry and effusivity, and local meteorology. Prevailing tradewinds typically carry the gases and aerosols released to the southwest, where they are further distributed by the regional wind regime. Episodes of kona, or low speed variable winds sometimes disrupt this pattern, however, and allow the gases and their oxidation products to collect at the summit and eastern side of the island. Summit solfatara areas of Kilauea are distinguished by moderate to high ambient SO{sub 2}, high H{sub 2}S at one location, and low H{sub 2}S at all others, and negligible HCl concentrations, as measured 1 m from degassing point-sources. Summit solfatara rain water has high sulfate and low chloride ion concentrations, and low pH.

  10. Restart of theory of air-breathing engines

    NASA Astrophysics Data System (ADS)

    Rester, Austin

    1992-07-01

    Expansion and compression ratios are treated as independent variables in the derivation of new equations for thermal efficiencies. A conceptual process of isentropic compression of exhaust gases to ambient conditions simplifies the equations for piston engines. Expansion is shown to govern thermal efficiency. A variable-process piston engine is introduced in this paper. Relative to 1/2 load conditions, this new engine is 25 percent more efficient than an Otto engine. Relative to full load, the new engine is 35 percent more powerful than a naturally-aspirated Otto engine. New energy-efficient gas turbines and turbo-jets which utilize pulse-combustion to maximize expansion of combustion gases are also introduced.

  11. Hydrogen chloride partitioning in a Titan III exhaust cloud diluted with ambient air

    NASA Technical Reports Server (NTRS)

    Sebacher, D. I.; Wornom, D. E.; Bendura, R. J.

    1979-01-01

    Measurements and analysis are presented of the partitioning of HCl between hydrochloric acid aerosol and gaseous HCl in a Titan III exhaust cloud, as the cloud is diluted with humid ambient air. Partitioning was determined by measuring the gaseous HCl concentration with a recently developed airborne Gas Filter Correlation detector and simultaneously with a chemiluminescence detector which measures total HCl. Although equilibrium predictions for HCl aerosol formation indicated that no HCl aerosol should exist in the exhaust cloud for the meteorological conditions of this launch, the measurements indicated significant HCl aerosol formation. These measurements will provide verification for advanced modeling programs now under development.

  12. Space Shuttle Main Engine Liquid Air Insulation Redesign Lessons Learned

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell; Carroll, Paul; Head, Kenneth; Fasheh, John; Stuart, Jessica

    2010-01-01

    The Space Shuttle Main Engine Liquid Air Insulation redesign was required to prevent the reoccurance of the STS-111 High Pressure Speed Sensor In-Flight Anomaly. The STS-111 In-Flight Anomaly Failure Investigation Team's initial redesign of the High Pressure Fuel Turbopump Pump End Ball Bearing Liquid Air Insulation failed the certification test by producing Liquid Air. The certification test failure indicated not only the High Pressure Fuel Turbopump Liquid Air Insulation, but all other Space Shuttle Main Engine Liquid Air Insulation. This paper will document the original Space Shuttle Main Engine Liquid Air STS-111 In-Flight Anomaly investigation, the heritage Space Shuttle Main Engine Insulation certification testing faults, the techniques and instrumentation used to accurately test the Liquid Air Insulation systems on the Stennis Space Center SSME test stand, the analysis techniques used to identify the Liquid Air Insulation problem areas and the analytical verification of the redesign before entering certification testing, Trade study down selected to three potential design solutions, the results of the development testing which down selected the final Liquid Air Redesign are also documented within this paper.

  13. 10. Building 105, Facilities Engineering Building, 1830, interior, air condition ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Building 105, Facilities Engineering Building, 1830, interior, air condition repair shop, S end of building, looking N. - Watervliet Arsenal, Building 105, South Broadway, on Hudson River, Watervliet, Albany County, NY

  14. Far Noise Field of Air Jets and Jet Engines

    NASA Technical Reports Server (NTRS)

    Callaghan, Edmund E; Coles, Willard D

    1957-01-01

    An experimental investigation was conducted to study and compare the acoustic radiation of air jets and jet engines. A number of different nozzle-exit shapes were studied with air jets to determine the effect of exit shape on noise generation. Circular, square, rectangular, and elliptical convergent nozzles and convergent-divergent and plug nozzles were investigated. The spectral distributions of the sound power for the engine and the air jet were in good agreement for the case where the engine data were not greatly affected by reflection or jet interference effects. Such power spectra for a subsonic or slightly choked engine or air jet show that the peaks of the spectra occur at a Strouhal number of 0.3.

  15. Personal and ambient exposures to air toxics in Camden, New Jersey.

    PubMed

    Lioy, Paul J; Fan, Zhihua; Zhang, Junfeng; Georgopoulos, Panos; Wang, Sheng-Wei; Ohman-Strickland, Pamela; Wu, Xiangmei; Zhu, Xianlei; Harrington, Jason; Tang, Xiaogang; Meng, Qingyu; Jung, Kyung Hwa; Kwon, Jaymin; Hernandez, Marta; Bonnano, Linda; Held, Joann; Neal, John

    2011-08-01

    Personal exposures and ambient concentrations of air toxics were characterized in a pollution "hot spot" and an urban reference site, both in Camden, New Jersey. The hot spot was the city's Waterfront South neighborhood; the reference site was a neighborhood, about 1 km to the east, around the intersection of Copewood and Davis streets. Using personal exposure measurements, residential ambient air measurements, statistical analyses, and exposure modeling, we examined the impact of local industrial and mobile pollution sources, particularly diesel trucks, on personal exposures and ambient concentrations in the two neighborhoods. Presented in the report are details of our study design, sample and data collection methods, data- and model-analysis approaches, and results and key findings of the study. In summary, 107 participants were recruited from nonsmoking households, including 54 from Waterfront South and 53 from the Copewood-Davis area. Personal air samples were collected for 24 hr and measured for 32 target compounds--11 volatile organic compounds (VOCs*), four aldehydes, 16 polycyclic aromatic hydrocarbons (PAHs), and particulate matter (PM) with an aerodynamic diameter < or = 2.5 microm (PM2.5). Simultaneously with the personal monitoring, ambient concentrations of the target compounds were measured at two fixed monitoring sites, one each in the Waterfront South and Copewood-Davis neighborhoods. To understand the potential impact of local sources of air toxics on personal exposures caused by temporal (weekdays versus weekend days) and seasonal (summer versus winter) variations in source intensities of the air toxics, four measurements were made of each subject, two in summer and two in winter. Within each season, one measurement was made on a weekday and the other on a weekend day. A baseline questionnaire and a time diary with an activity questionnaire were administered to each participant in order to obtain information that could be used to understand

  16. CO2 Capture from Ambient Air by Crystallization with a Guanidine Sorbent

    DOE PAGES

    Seipp, Charles A.; Univ. of Texas, Austin, TX; Williams, Neil J.; ...

    2016-12-21

    Carbon capture and storage is an important strategy for stabilizing the increasing concentration of atmospheric CO2 and the global temperature. A possible approach toward reversing this trend and decreasing the atmospheric CO2 concentration is to remove the CO2 directly from air (direct air capture). In this paper, we report a simple aqueous guanidine sorbent that captures CO2 from ambient air and binds it as a crystalline carbonate salt by guanidinium hydrogen bonding. The resulting solid has very low aqueous solubility (Ksp=1.0(4)×10-8), which facilitates its separation from solution by filtration. The bound CO2 can be released by relatively mild heating ofmore » the crystals at 80–120 °C, which regenerates the guanidine sorbent quantitatively. Finally and thus, this crystallization-based approach to CO2 separation from air requires minimal energy and chemical input, and offers the prospect for low-cost direct air capture technologies.« less

  17. Moisture-swing sorption for carbon dioxide capture from ambient air: a thermodynamic analysis.

    PubMed

    Wang, Tao; Lackner, Klaus S; Wright, Allen B

    2013-01-14

    An ideal chemical sorbent for carbon dioxide capture from ambient air (air capture) must have a number of favourable properties, such as environmentally benign behaviour, a high affinity for CO(2) at very low concentration (400 ppm), and a low energy cost for regeneration. The last two properties seem contradictory, especially for sorbents employing thermal swing adsorption. On the other hand, thermodynamic analysis shows that the energy cost of an air capture device need only be slightly larger than that of a flue gas scrubber. The moisture swing separation process studied in this paper provides a novel approach to low cost CO(2) capture from air. The anionic exchange resin sorbent binds CO(2) when dry and releases it when wet. A thermodynamic model with coupled phase and chemical equilibria is developed to study the complex H(2)O-CO(2)-resin system. The moisture swing behaviour is compatible with hydration energies changing with the activity of water on the resin surfaces. This activity is in turn set by the humidity. The rearrangement of hydration water on the resin upon the sorption of a CO(2) molecule is predicted as a function of the humidity and temperature. Using water as fuel to drive the moisture swing enables an economical, large-scale implementation of air capture. By generating CO(2) with low partial pressures, the present technology has implications for in situ CO(2) utilizations which require low pressure CO(2) gas rather than liquid CO(2).

  18. CO2 Capture from Ambient Air by Crystallization with a Guanidine Sorbent

    SciTech Connect

    Seipp, Charles A.; Williams, Neil J.; Kidder, Michelle K.; Custelcean, Radu

    2016-12-21

    Carbon capture and storage is an important strategy for stabilizing the increasing concentration of atmospheric CO2 and the global temperature. A possible approach toward reversing this trend and decreasing the atmospheric CO2 concentration is to remove the CO2 directly from air (direct air capture). In this paper, we report a simple aqueous guanidine sorbent that captures CO2 from ambient air and binds it as a crystalline carbonate salt by guanidinium hydrogen bonding. The resulting solid has very low aqueous solubility (Ksp=1.0(4)×10-8), which facilitates its separation from solution by filtration. The bound CO2 can be released by relatively mild heating of the crystals at 80–120 °C, which regenerates the guanidine sorbent quantitatively. Finally and thus, this crystallization-based approach to CO2 separation from air requires minimal energy and chemical input, and offers the prospect for low-cost direct air capture technologies.

  19. Air Force Civil Engineer, Volume 15, Number 2, 2007

    DTIC Science & Technology

    2007-01-01

    dedicated to it. Civil engineers at Air Force Materiel Command are learning to take it just as seriously. The Transformation plan for Air Force...engineering processes and discussed lessons learned from previous conversions to civilian workforces within AFMC, from A76 or direct actions. “I think it...we don’t have to spend that time learning in Afghanistan or Iraq and can use that time to focus on the mission and learning our area of operations

  20. AMBIENT AIR MONITORING AT GROUND ZERO AND LOWER MANHATTAN FOLLOWING THE COLLAPSE OF THE WORLD TRADE CENTER

    EPA Science Inventory

    The U.S. EPA National Exposure Research Laboratory (NERL) collaborated with EPA's Regional offices to establish a monitoring network to characterize ambient air concentrations of particulate matter (PM) and air toxics in lower Manhattan following the collapse of the World Trade...

  1. Review of the Primary National Ambient Air Quality Standards for Nitrogen Dioxide: Risk and Exposure Assessment Planning Document

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) is conducting a review of the air quality criteria and the primary (health-based) national ambient air quality standards (NAAQS) for nitrogen dioxide (NO2). The major phases of the process for reviewing NAAQS include the following: (...

  2. 40 CFR Appendix N to Part 50 - Interpretation of the National Ambient Air Quality Standards for PM2.5

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Air Quality Standards for PM2.5 N Appendix N to Part 50 Protection of Environment ENVIRONMENTAL.... 50, App. N Appendix N to Part 50—Interpretation of the National Ambient Air Quality Standards for PM2... used for performing calculations in appendix N. It represents data for the primary monitors...

  3. 40 CFR Appendix N to Part 50 - Interpretation of the National Ambient Air Quality Standards for PM2.5

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Air Quality Standards for PM2.5 N Appendix N to Part 50 Protection of Environment ENVIRONMENTAL.... 50, App. N Appendix N to Part 50—Interpretation of the National Ambient Air Quality Standards for PM2... used for performing calculations in appendix N. It represents data for the primary monitors...

  4. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion...

  5. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion...

  6. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion...

  7. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion...

  8. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion...

  9. 40 CFR Appendix N to Part 50 - Interpretation of the National Ambient Air Quality Standards for PM2.5

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Air Quality Standards for PM2.5 N Appendix N to Part 50 Protection of Environment ENVIRONMENTAL.... 50, App. N Appendix N to Part 50—Interpretation of the National Ambient Air Quality Standards for PM2...) for the annual creditable number of samples for year y (cny). The corresponding “n” value in the...

  10. An update to the ambient ratio method for 1-h NO2 air quality standards dispersion modeling

    NASA Astrophysics Data System (ADS)

    Podrez, Mark

    2015-02-01

    Nitrogen oxide (NOX) gases are typically emitted by fuel combustion sources in the form of nitric oxide (NO), which then reacts with ozone and other oxidants in the atmosphere to convert a portion of the NO to nitrogen dioxide (NO2). EPA has promulgated a 1-h average National Ambient Air Quality Standard (NAAQS) for NO2, and major sources of NOX emissions must estimate their NO2 air quality impacts as part of EPA's air quality permitting programs. The AERMOD dispersion model has been developed by EPA for these air quality impact analyses, and AERMOD contains three different NO to NO2 conversion methods for estimating the ambient concentrations of NO2. This paper describes a refinement to one of the methods, the Ambient Ratio Method version 2 (ARM2). ARM2 is an empirical approach that uses a variable conversion factor, based on an analysis of ambient air measurements of NO and NO2, to estimate the portion of the AERMOD predicted air concentration of total NOX species that is in the form of NO2. The performance of ARM2 has been evaluated and found to compare well to actual ambient measurements and to other more complex EPA conversion methods. EPA has included ARM2 as a "beta-testing" option in AERMOD version 14134, and provided guidance on the use of ARM2 for regulatory modeling analyses in a September 2014 memorandum. This paper also discusses this recent EPA guidance.

  11. Turbine airfoil with ambient cooling system

    DOEpatents

    Campbell, Jr, Christian X.; Marra, John J.; Marsh, Jan H.

    2016-06-07

    A turbine airfoil usable in a turbine engine and having at least one ambient air cooling system is disclosed. At least a portion of the cooling system may include one or more cooling channels configured to receive ambient air at about atmospheric pressure. The ambient air cooling system may have a tip static pressure to ambient pressure ratio of at least 0.5, and in at least one embodiment, may include a tip static pressure to ambient pressure ratio of between about 0.5 and about 3.0. The cooling system may also be configured such that an under root slot chamber in the root is large to minimize supply air velocity. One or more cooling channels of the ambient air cooling system may terminate at an outlet at the tip such that the outlet is aligned with inner surfaces forming the at least one cooling channel in the airfoil to facilitate high mass flow.

  12. Optical and electron microscopy can be used to determine asbestos in ambient air

    SciTech Connect

    Warner, M.

    1988-03-15

    Because it resists acids, is noncombustible, and can be woven into fabrics, asbestos was commonly used as fire-proofing and insulation in many buildings built before the mid-1970s as well as in brake linings, heat-proof gloves, and other commercial products. Concern about adverse effects on health from exposure to asbestos originally centered on miners, insulation workers, and others who were exposed to large amounts of asbestos in their jobs. But recent studies indicate that even low levels of airborne asbestos may cause cancer, and concern has mounted over the effects on the general public of exposure to asbestos in the environment. Because most of the methods that were developed for the analysis of bulk asbestos samples are not appropriate for the analysis of air samples, new methods capable of detecting small amounts of asbestos in ambient air have been developed. These new methods are described.

  13. Third harmonic generation in air ambient and laser ablated carbon plasma

    SciTech Connect

    Singh, Ravi Pratap Gupta, Shyam L.; Thareja, Raj K.

    2015-12-15

    We report the third harmonic generation of a nanosecond laser pulse (1.06 μm) in air ambient and in the presence of nanoparticles from laser ablated carbon plasma. Significant decrease in the threshold of third harmonic generation and multi-fold increment in the intensity of generated third harmonic is observed in presence of carbon plasma. The third harmonic in air is due to the quasi-resonant four photon process involving vibrationally excited states of molecular ion of nitrogen due to electron impact ionization and laser pulse. Following optical emission spectroscopic observations we conclude that the presence of C{sub 2} and CN in the ablated plume play a vital role in the observed third harmonic signals.

  14. [Acute effect of ambient air pollution on small airway lung functions among school children in Shanghai].

    PubMed

    Zhang, L J; Guo, C Y; Xu, H H; Xu, D; Shen, X B; Du, X Y; Zhang, M H; Tan, J G; Zhang, J H; Dong, C Y; Qian, H L; Shi, Y W; Pan, M Z; Zhou, X D

    2017-02-10

    Objective: To study the acute effects of compound ambient air pollution on small airway lung functions among school children in Shanghai. Method: A longitudinal survey on lung functions was conducted among 233 school-children from three schools (A, B and C, located in innerring, mid-ring and outer-ring areas). Lung function test was performed once a week for 3 times respectively, among children in school A and B in Dec. 2013 and in school C in Dec. 2014. The fourth lung function test was tested in Jun. 2014 and May 2015 in the respective schools. Results: from the lung function would include items as: forced mid-expiratory flow at 25% of forced vital capacity (MEF(25%)), mid-expiratory flow at 50% of forced vital capacity (MEF(50%)), mid-expiratory flow at 75% of forced vital capacity (MEF(75%)) and mid-expiratory flow between 25% and 75% of the forced vital capacity (FEF(25%-75%)). Data regarding the daily air quality real-time of PM(2.5), PM(10), SO(2) and NO(2) in Dec. 2013, Dec. 2014, Jun. 2014 and May. 2015 from the three environmental monitoring spots and meteorological data from the Shanghai Meteorological Service system which were physically close to the three schools, were collected simultaneously. Linear mixed effect model was used to examine the levels of correlation between lung function indicators and ambient air pollutants. Results When confounding factors on meteorology and individuals were controlled, the lag effects and accumulated lag effects were found to have existed between the internal quarter rang (IQR) concentration of PM(2.5) and PM(10) in lag2 day and lag02 days, IQR concentration of SO(2) in lag02 day and IQR concentration of NO(2) lag0 day, when small airway lung functions like MEF(25%), MEF(50%), MEF(75%) and FEF(25%-75%)(P<0.05) were inspected. Results from the two air pollutants model analysis showed that SO(2) and NO(2) presenting interactive effects with PM(2.5), PM(10) and lag effects more significant than the individual SO(2) and

  15. Ambient air pollution and pregnancy-induced hypertensive disorders: a systematic review and meta-analysis.

    PubMed

    Pedersen, Marie; Stayner, Leslie; Slama, Rémy; Sørensen, Mette; Figueras, Francesc; Nieuwenhuijsen, Mark J; Raaschou-Nielsen, Ole; Dadvand, Payam

    2014-09-01

    Pregnancy-induced hypertensive disorders can lead to maternal and perinatal morbidity and mortality, but the cause of these conditions is not well understood. We have systematically reviewed and performed a meta-analysis of epidemiological studies investigating the association between exposure to ambient air pollution and pregnancy-induced hypertensive disorders including gestational hypertension and preeclampsia. We searched electronic databases for English language studies reporting associations between ambient air pollution and pregnancy-induced hypertensive disorders published between December 2009 and December 2013. Combined risk estimates were calculated using random-effect models for each exposure that had been examined in ≥4 studies. Heterogeneity and publication bias were evaluated. A total of 17 articles evaluating the impact of nitrogen oxides (NO2, NOX), particulate matter (PM10, PM2.5), carbon monoxide (CO), ozone (O3), proximity to major roads, and traffic density met our inclusion criteria. Most studies reported that air pollution increased risk for pregnancy-induced hypertensive disorders. There was significant heterogeneity in meta-analysis, which included 16 studies reporting on gestational hypertension and preeclampsia as separate or combined outcomes; there was less heterogeneity in findings of the 10 studies reporting solely on preeclampsia. Meta-analyses showed increased risks of hypertensive disorders in pregnancy for all pollutants except CO. Random-effect meta-analysis combined odds ratio associated with a 5-μg/m3 increase in PM2.5 was 1.57 (95% confidence interval, 1.26-1.96) for combined pregnancy-induced hypertensive disorders and 1.31 (95%confidence interval, 1.14-1.50) for preeclampsia [corrected]. Our results suggest that exposure to air pollution increases the risk of pregnancy-induced hypertensive disorders.

  16. Assessment of selected metals in the ambient air PM10 in urban sites of Bangkok (Thailand).

    PubMed

    Pongpiachan, Siwatt; Iijima, Akihiro

    2016-02-01

    Estimating the atmospheric concentrations of PM10-bounded selected metals in urban air is crucial for evaluating adverse health impacts. In the current study, a combination of measurements and multivariate statistical tools was used to investigate the influence of anthropogenic activities on variations in the contents of 18 metals (i.e., Al, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Ba, La, Ce and Pb) in ambient air. The concentrations of PM10-bounded metals were measured simultaneously at eight air quality observatory sites during a half-year period at heavily trafficked roads and in urban residential zones in Bangkok, Thailand. Although the daily average concentrations of Al, V, Cr, Mn and Fe were almost equivalent to those of other urban cities around the world, the contents of the majority of the selected metals were much lower than the existing ambient air quality guidelines and standard limit values. The sequence of average values of selected metals followed the order of Al > Fe > Zn > Cu > Pb > Mn > Ba > V > Sb > Ni > As > Cr > Cd > Se > Ce > La > Co > Sc. The probability distribution function (PDF) plots showed sharp symmetrical bell-shaped curves in V and Cr, indicating that crustal emissions are the predominant sources of these two elements in PM10. The comparatively low coefficients of divergence (COD) that were found in the majority of samples highlight that site-specific effects are of minor importance. A principal component analysis (PCA) revealed that 37.74, 13.51 and 11.32 % of the total variances represent crustal emissions, vehicular exhausts and the wear and tear of brakes and tires, respectively.

  17. The Air Force and the Great Engine War,

    DTIC Science & Technology

    1987-01-01

    quickly as the Air Force wanted because of haggling over business terms. So at an Atlanta airport hotel , the Air Force and Pratt met quict’y and produced...6,3-64 prodluction slip, 34-35 55-58.test %lips. 32-33 engine stress factors re- thst saisf 323 defined 58-63 thrust not stisfactory 137 fan problems

  18. South elevation of equipment building. Hood covers engine room air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South elevation of equipment building. Hood covers engine room air intake. Engine exhaust is above hood, and door opens to heater room. Cable duct to tower is at right. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  19. Implications of Nitrogen-Climate Interactions for Ambient Air Pollution and Human Health

    NASA Astrophysics Data System (ADS)

    Haeuber, R.; Peel, J. L.; Garcia, V.; Neas, L.; Russell, A. G.

    2011-12-01

    Nitrogen oxides (NOX) are important components of ambient and indoor air pollution and are emitted from a range of combustion sources, including on-road mobile sources, electric power generators, and non-road mobile sources. While anthropogenic sources dominate, NOX is also formed by lightning and wildland fires and is emitted by soil. Reduced nitrogen (e.g., ammonia, NH3) is also emitted by various sources, including fertilizer application and animal waste decomposition. NOX, ozone and PM2.5 pollution related to atmospheric emissions of nitrogen and other pollutants can cause premature death and a variety of serious health effects. Climate change is expected to impact how nitrogen-related pollutants affect human health. For example, changes in temperature and precipitation patterns are projected to both lengthen the ozone season and intensify high ozone episodes in some areas. Other climate-related changes may increase the atmospheric release of nitrogen compounds through impacts on wildfire regimes, soil emissions, and biogenic emissions from terrestrial ecosystems. This session will examine the potential human health implications of climate change and nitrogen cycle interactions related to ambient air pollution.

  20. Assessment of reduced sulfur compounds in ambient air as malodor components in an urban area

    NASA Astrophysics Data System (ADS)

    Susaya, Janice; Kim, Ki-Hyun; Phan, Nhu-Thuc; Kim, Jo-Chun

    2011-07-01

    Long-term monitoring of reduced sulfur compounds (RSCs: hydrogen sulfide (H 2S), methanethiol (CH 3SH), dimethyl sulfide (DMS), and dimethyl disulfide (DMDS)) in ambient air was made using an on-line GC system at an odor monitoring station in the city of Ansan, South Korea (August 2005-December 2007). The results were examined to assess the status of RSC pollution, its relative contribution to malodor, and the controlling factors of its occurrence. H 2S (mean of 0.27 ppb) was eminent in terms of both magnitude and occurrence frequency, while others were not with mean values of 0.11 (DMDS), 0.10 (DMS), and 0.07 ppb (CH 3SH). Unlike others, the temporal trends of H 2S were best represented by the combined effects of its source processes and meteorological conditions. The results of correlation analysis indicate strong correlations between RSCs and water-related parameters (e.g., rainfall, dew point, and relative humidity). The role of RSCs as malodor component appears to be pronounced during nighttime, especially in summer. If the relative contribution of RSCs to malodor is assessed by means of the sum of odor intensity (SOI), its impact is relatively low, with an SOI value of 1.22 (weak odor strength). Consequently, a more deliberate approach may be needed to effectively assess odor occurrence patterns in ambient air.

  1. Biofilm Formation Derived from Ambient Air and the Characteristics of Apparatus

    NASA Astrophysics Data System (ADS)

    Kanematsu, H.; Kougo, H.; Kuroda, D.; Itho, H.; Ogino, Y.; Yamamoto, Y.

    2013-04-01

    Biofilm is a kind of thin film on solidified matters, being derived from bacteria. Generally, planktonic bacteria float in aqueous environments, soil or air, most of which can be regarded as oligotrophic environments. Since they have to survive by instinct, they seek for nutrients that would exist on materials surfaces as organic matters. Therefore, bacteria attach materials surfaces reversibly. The attachment and detachment repeat for a while and finally, they attach on them irreversibly and the number of bacteria on them increases. At a threshold number, bacteria produce polymeric matters at the same time by quorum sensing mechanism and the biofilm produces on material surfaces. The biofilm produced in that way generally contains water (more than 80%), EPS (Exopolymeric Substance) and bacteria themselves. And they might bring about many industrial problems, fouling, corrosion etc. Therefore, it is very important for us to control and prevent the biofilm formation properly. However, it is generally very hard to produce biofilm experimentally and constantly in ambient atmosphere on labo scale. The authors invented an apparatus where biofilm could form on specimen's surfaces from house germs in the ambient air. In this experiment, we investigated the basic characteristics of the apparatus, reproducibility, the change of biofilm with experimental time, the quality change of water for biofilm formation and their significance for biofilm research.

  2. Efficient and stable perovskite solar cells prepared in ambient air irrespective of the humidity

    PubMed Central

    Tai, Qidong; You, Peng; Sang, Hongqian; Liu, Zhike; Hu, Chenglong; Chan, Helen L. W.; Yan, Feng

    2016-01-01

    Poor stability of organic–inorganic halide perovskite materials in humid condition has hindered the success of perovskite solar cells in real applications since controlled atmosphere is required for device fabrication and operation, and there is a lack of effective solutions to this problem until now. Here we report the use of lead (II) thiocyanate (Pb(SCN)2) precursor in preparing perovskite solar cells in ambient air. High-quality CH3NH3PbI3−x(SCN)x perovskite films can be readily prepared even when the relative humidity exceeds 70%. Under optimized processing conditions, we obtain devices with an average power conversion efficiency of 13.49% and the maximum efficiency over 15%. In comparison with typical CH3NH3PbI3-based devices, these solar cells without encapsulation show greatly improved stability in humid air, which is attributed to the incorporation of thiocyanate ions in the crystal lattice. The findings pave a way for realizing efficient and stable perovskite solar cells in ambient atmosphere. PMID:27033249

  3. Environmental Resources of Selected Areas of Hawaii: Climate, Ambient Air Quality, and Noise (DRAFT)

    SciTech Connect

    Lombardi, D.A.; Blasing, T.J.; Easterly, C.E.; Hamilton, C.B.

    1994-06-01

    This report has been prepared to make available and archive background scientific data and related information on climate, ambient air quality, and ambient noise levels collected during the preparation of the environmental impact statement (EIS) for Phases 3 and 4 of the Hawaii Geothermal Project (HGP) as defined by the state of hawaii in its April 1989 proposal to Congress. The US Department of Energy (DOE) published a notice in the Federal Register on May 17, 1994 withdrawing its Notice of Intent of February 14, 1992, to prepare the HGP-EIS. Since the state of Hawaii is no longer pursuing or planning to pursue the HGP, DOE considers the project to be terminated. The report presents a general description of the climate and air quality for the islands of Hawaii (henceforth referred to as Hawaii), Maui, and Oahu. It also presents a literature review as baseline information on the health effects of hydrogen sulfide. the scientific background data and related information is being made available for use by others in conducting future scientific research in these areas. This report describes the environmental resources present in the areas studied (i.e., the affected environment) and does not represent an assessment of environmental impacts.

  4. Environmental resources of selected areas of Hawaii: Climate, ambient air quality, and noise

    SciTech Connect

    Lombardi, D.A.; Blasing, T.J.; Easterly, C.E.; Reed, R.M.; Hamilton, C.B.

    1995-03-01

    This report has been prepared to make available and archive background scientific data and related information on climate, ambient air quality, and ambient noise levels collected during the preparation of the environmental impact statement (EIS) for Phases 3 and 4 of the Hawaii Geothermal Project (HGP) as defined by the state of Hawaii in its April 1989 proposal to Congress. The US Department of Energy (DOE) published a notice withdrawing its Notice of Intent to prepare the HGP-EIS. Since the state of Hawaii is no longer pursuing or planning to pursue the HGP, DOE considers the project to be terminated. The report presents a general description of the climate add air quality for the islands of Hawaii (henceforth referred to as Hawaii), Maui and Oahu. It also presents a literature review as baseline information on the health effects of sulfide. The scientific background data and related information is being made available for use by others in conducting future scientific research in these areas. This report describes the environmental resources present in the areas studied (i.e., the affected environment) and does not represent an assessment of environmental impacts.

  5. A Course in Air Pollution for Engineers.

    ERIC Educational Resources Information Center

    Seapan, Mayis

    1982-01-01

    An air pollution course covering both the fundamentals and control of air pollution introduces a new sequential structure for its topic presentation. The new structure is built on the basis of theoretical principles and has minimized the traditional case study approach. A detailed course outline is included. (Author/JN)

  6. Ambient air pollution, traffic noise and adult asthma prevalence: a BioSHaRE approach.

    PubMed

    Cai, Yutong; Zijlema, Wilma L; Doiron, Dany; Blangiardo, Marta; Burton, Paul R; Fortier, Isabel; Gaye, Amadou; Gulliver, John; de Hoogh, Kees; Hveem, Kristian; Mbatchou, Stéphane; Morley, David W; Stolk, Ronald P; Elliott, Paul; Hansell, Anna L; Hodgson, Susan

    2017-01-01

    We investigated the effects of both ambient air pollution and traffic noise on adult asthma prevalence, using harmonised data from three European cohort studies established in 2006-2013 (HUNT3, Lifelines and UK Biobank).Residential exposures to ambient air pollution (particulate matter with aerodynamic diameter ≤10 µm (PM10) and nitrogen dioxide (NO2)) were estimated by a pan-European Land Use Regression model for 2007. Traffic noise for 2009 was modelled at home addresses by adapting a standardised noise assessment framework (CNOSSOS-EU). A cross-sectional analysis of 646 731 participants aged ≥20 years was undertaken using DataSHIELD to pool data for individual-level analysis via a "compute to the data" approach. Multivariate logistic regression models were fitted to assess the effects of each exposure on lifetime and current asthma prevalence.PM10 or NO2 higher by 10 µg·m(-3) was associated with 12.8% (95% CI 9.5-16.3%) and 1.9% (95% CI 1.1-2.8%) higher lifetime asthma prevalence, respectively, independent of confounders. Effects were larger in those aged ≥50 years, ever-smokers and less educated. Noise exposure was not significantly associated with asthma prevalence.This study suggests that long-term ambient PM10 exposure is associated with asthma prevalence in western European adults. Traffic noise is not associated with asthma prevalence, but its potential to impact on asthma exacerbations needs further investigation.

  7. Optimization of Air-Breathing Propulsion Engine Concepts

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Hopkins, Dale A.

    1997-01-01

    Air-breathing propulsion engines play an important role in the development of both civil and military aircraft Design optimization of such engines can lead to higher power, or more thrust for less fuel consumption. A multimission propulsion engine design can be modeled mathematically as a multivariable global optimization problem, with a sequence of subproblems, which are specific to the mission events defined through Mach number, altitude, and power setting combinations.

  8. Air Force Civil Engineer, Volume 11, Number 2, Summer 2003

    DTIC Science & Technology

    2003-01-01

    meet national safety standards. While deployed, the 437th CES supported Operation ENDURING FREEDOM � leading a combined force of 190 engineers in...Engineer. I am proud to serve our excellent leadership and our great nation . I look forward to serving with each of you � civilian, contractor, airman...tyndall.af.mil 19 Airfield Engineering 12 Meeting the Challenge 15 Keeping the Show on the Road 16 Air Expeditionary Warriors Buzz and Boom No More

  9. Air Force Civil Engineer, Volume 15, Number 3, 2007

    DTIC Science & Technology

    2007-01-01

    an independent ser- vice, it’s appropriate that we reflect on the history of “aviation engineers.” Civil Engineering has a rich and celebrated...continued evolution of the current civil engineer construct and a return to our “installation engineering” roots. By reevaluating the capabilities...traditions, some inherited from the national fire orga- nizations, and others taken from our rich Air Force history . In transforming into the most

  10. Curved centerline air intake for a gas turbine engine

    NASA Technical Reports Server (NTRS)

    Ruehr, W. C.; Younghans, J. L.; Smith, E. B. (Inventor)

    1980-01-01

    An inlet for a gas turbine engine was disposed about a curved centerline for the purpose of accepting intake air that is flowing at an angle to engine centerline and progressively turning that intake airflow along a curved path into alignment with the engine. This curved inlet is intended for use in under the wing locations and similar regions where airflow direction is altered by aerodynamic characteristics of the airplane. By curving the inlet, aerodynamic loss and acoustic generation and emission are decreased.

  11. Ambient Particulate Matter Air Pollution in Mpererwe District, Kampala, Uganda: A Pilot Study

    PubMed Central

    Schwander, Stephan; Okello, Clement D.; Freers, Juergen; Chow, Judith C.; Watson, John G.; Corry, Melody; Meng, Qingyu

    2014-01-01

    Air quality in Kampala, the capital of Uganda, has deteriorated significantly in the past two decades. We made spot measurements in Mpererwe district for airborne particulate matter PM2.5 (fine particles) and coarse particles. PM was collected on Teflon-membrane filters and analyzed for mass, 51 elements, 3 anions, and 5 cations. Both fine and coarse particle concentrations were above 100 µg/m3 in all the samples collected. Markers for crustal/soil (e.g., Si and Al) were the most abundant in the PM2.5 fraction, followed by primary combustion products from biomass burning and incinerator emissions (e.g., K and Cl). Over 90% of the measured PM2.5 mass can be explained by crustal species (41% and 59%) and carbonaceous aerosol (33%–55%). Crustal elements dominated the coarse particles collected from Kampala. The results of this pilot study are indicative of unhealthy air and suggest that exposure to ambient air in Kampala may increase the burden of environmentally induced cardiovascular, metabolic, and respiratory diseases including infections. Greater awareness and more extensive research are required to confirm our findings, to identify personal exposure and pollution sources, and to develop air quality management plans and policies to protect public health. PMID:24693293

  12. The association of ambient air pollution with airway inflammation in schoolchildren.

    PubMed

    Chen, Bing-Yu; Chan, Chang-Chuan; Lee, Chung-Te; Cheng, Tsun-Jen; Huang, Wen-Chuan; Jhou, Ji-Ci; Han, Yueh-Ying; Chen, Chu-Chih; Guo, Yue Leon

    2012-04-15

    The biologic mechanisms involved in airway inflammatory response to air pollution are not clearly understood. The authors conducted a longitudinal study to investigate whether exposure to ambient air pollutants affected inflammatory cells and mediators from nasal lavage in schoolchildren. Study participants were 100 elementary and middle-school students in New Taipei City, Taiwan. A structured respiratory health questionnaire was administered in September 2007, followed by monthly measurement of nasal inflammation from October 2007 to November 2009. During the study period, daily concentrations of air pollutants were obtained from the Environmental Protection Administration monitoring station and the Aerosol Supersite. Mixed-effects models were applied to examine the association between air pollution and nasal inflammatory cells and mediators, including percentages of neutrophils, eosinophils, and monocytes in lavaged cells and interleukin-8. A total of 824 measurements were obtained from 100 participants over a period of 10 months. The level of particulate matter with an aerodynamic diameter of 2.5 μm or less (PM(2.5)) was found to be associated with percentage of neutrophils (β = 3.45%, 95% confidence interval: 0.89, 6.01) and interleukin-8 level (β = 29.98 pg/mL, 95% confidence interval: 3.26, 56.69) in the nasal lavage on the day of exposure. In this longitudinal cohort study of schoolchildren, results indicated that exposure to PM(2.5) might induce nasal inflammation.

  13. Ambient air pollution, temperature and out-of-hospital coronary deaths in Shanghai, China.

    PubMed

    Dai, Jinping; Chen, Renjie; Meng, Xia; Yang, Changyuan; Zhao, Zhuohui; Kan, Haidong

    2015-08-01

    Few studies have evaluated the effects of ambient air pollution and temperature in triggering out-of-hospital coronary deaths (OHCDs) in China. We evaluated the associations of air pollution and temperature with daily OHCDs in Shanghai, China from 2006 to 2011. We applied an over-dispersed generalized additive model and a distributed lag nonlinear model to analyze the effects of air pollution and temperature, respectively. A 10 μg/m(3) increase in the present-day PM10, PM2.5, SO2, NO2 and CO were associated with increases in OHCD mortality of 0.49%, 0.68%, 0.88%, 1.60% and 0.08%, respectively. A 1 °C decrease below the minimum-mortality temperature corresponded to a 3.81% increase in OHCD mortality on lags days 0-21, and a 1 °C increase above minimum-mortality temperature corresponded to a 4.61% increase over lag days 0-3. No effects were found for in-hospital coronary deaths. This analysis suggests that air pollution, low temperature and high temperature may increase the risk of OHCDs.

  14. A Review of Epidemiological Research on Adverse Neurological Effects of Exposure to Ambient Air Pollution

    PubMed Central

    Xu, Xiaohui; Ha, Sandie Uyen; Basnet, Rakshya

    2016-01-01

    There is a growing body of epidemiological research reporting the neurological effects of ambient air pollution. We examined current evidence, identified the strengths and weaknesses of published epidemiological studies, and suggest future directions for research in this area. Studies were identified through a systematic search of online scientific databases, in addition to a manual search of the reference lists from the identified papers. Despite being a relatively new area of investigation, overall, there is mounting evidence implicating adverse effects of air pollution on neurobehavioral function in both adults and children. Further research is needed to expand our understanding of these relationships, including improvement in the accuracy of exposure assessments; focusing on specific toxicants and their relationships to specific health endpoints, such as neurodevelopmental disorders and neurodegenerative diseases; investigating the combined neurological effects of multiple air pollutants; and further exploration of genetic susceptibility for neurotoxicity of air pollution. In order to achieve these goals collaborative efforts are needed from multidisciplinary teams, including experts in toxicology, biostatistics, geographical science, epidemiology, and neurology. PMID:27547751

  15. Nanosecond Glow and Spark Discharges in Ambient Air and in Water Vapor

    NASA Astrophysics Data System (ADS)

    Laux, Christophe; Rusterholtz, Diane; Sainct, Florent; Xu, Da; Lacoste, Deanna; Stancu, Gabi; Pai, David

    2013-09-01

    Nanosecond repetitively pulsed (NRP) discharges are one of the most energy efficient ways to produce active species in atmospheric pressure gases. In both air and water vapor, three discharge regimes can be obtained: 1) corona, with light emission just around the anode, 2) glow, corresponding to a diffuse nonequilibrium plasma, and 3) spark, characterized by higher temperatures and higher active species densities. The glow regime was initially obtained in air preheated at 2000 K. Based on a model defining the transition between glow and spark, we recently succeeded in obtaining a stable glow in ambient air at 300 K, using a judicious combination of electrode geometry, pulse duration, pulse frequency, and applied voltage. We will present these results and describe the characteristics of the discharge obtained in room air. The spark regime was also studied. NRP sparks induce ultrafast gas heating (about 1000 K in 20 ns) and high oxygen dissociation (up to 50% dissociation of O2) . This phenomenon can be explained by a two-step process involving the excitation of molecular nitrogen followed by exothermic dissociative quenching of molecular oxygen. The characteristics of NRP discharges in water vapor will also be discussed. This work is supported by the ANR PREPA program (grant number ANR-09-BLAN-0043).

  16. A proposed methodology for the assessment of arsenic, nickel, cadmium and lead levels in ambient air.

    PubMed

    Santos, Germán; Fernández-Olmo, Ignacio

    2016-06-01

    Air quality assessment, required by the European Union (EU) Air Quality Directive, Directive 2008/50/EC, is part of the functions attributed to Environmental Management authorities. Based on the cost and time consumption associated with the experimental works required for the air quality assessment in relation to the EU-regulated metal and metalloids, other methods such as modelling or objective estimation arise as competitive alternatives when, in accordance with the Air Quality Directive, the levels of pollutants permit their use at a specific location. This work investigates the possibility of using statistical models based on Partial Least Squares Regression (PLSR) and Artificial Neural Networks (ANNs) to estimate the levels of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in ambient air and their application for policy purposes. A methodology comprising the main steps that should be taken into consideration to prepare the input database, develop the model and evaluate their performance is proposed and applied to a case of study in Santander (Spain). It was observed that even though these approaches present some difficulties in estimating the individual sample concentrations, having an equivalent performance they can be considered valid for the estimation of the mean values - those to be compared with the limit/target values - fulfilling the uncertainty requirements in the context of the Air Quality Directive. Additionally, the influence of the consideration of input variables related to atmospheric stability on the performance of the studied statistical models has been determined. Although the consideration of these variables as additional inputs had no effect on As and Cd models, they did yield an improvement for Pb and Ni, especially with regard to ANN models.

  17. Short-term effect of ambient air pollution on COPD mortality in four Chinese cities

    NASA Astrophysics Data System (ADS)

    Meng, Xia; Wang, Cuicui; Cao, Dachun; Wong, Chit-Ming; Kan, Haidong

    2013-10-01

    Ambient air pollution has been associated with increased mortality and morbidity; however, few studies have examined the short-term effect of air pollution specifically on chronic obstructive pulmonary disease (COPD), which is an important cause of mortality and morbidity world wide. In this analysis, we examined the associations between daily air pollution levels [particulate matter less than 10 microns in aerodynamic diameter (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2)] and COPD mortality in four Chinese cities. We used Poisson regression models with natural spline smoothing functions to adjust for long-term and seasonal trends of COPD mortality, as well as other time-varying covariates. We did a meta-analysis to obtain the 4-city average estimates. Air pollution (PM10, SO2, and NO2) was found to be associated with increased risk of COPD mortality in these four cities. Using the random-effects model, an increase of 10 μg m-3 of 2-day moving average concentrations of PM10, SO2 and NO2 corresponded to a 0.78% (95% CI, 0.13-1.42), 1.30% (95% CI, 0.61-1.99), and 1.78% (95% CI, 1.10-2.46) increase of COPD mortality, respectively. The concentration-response curves indicated linear associations without threshold. Only NO2 remained significant in the multi-pollutant models. To our knowledge, this is the first multi-city study in Asian developing region to report the short-term effect of air pollution on COPD mortality. Our results contribute to very limited data on the effects of air pollution on COPD mortality for high exposure settings typical in developing countries.

  18. Acoustic resonance phenomena in air bleed channels in aviation engines

    NASA Astrophysics Data System (ADS)

    Aleksentsev, A. A.; Sazhenkov, A. N.; Sukhinin, S. V.

    2016-11-01

    The existence of axial-radial acoustic resonance oscillations of the basic air flow in bleed channels of aviation engines is demonstrated theoretically and experimentally. Numerical and analytical methods are used to determine the frequency of acoustic resonance oscillations for the lowest modes of open and closed bleed channels of the PS-90A engine. Experimental investigations reveal new acoustic resonance phenomena arising in the air flow in bleed channel cavities in the core duct of this engine owing to instability of the basic air flow. The results of numerical, analytical, and experimental studies of the resonance frequencies reached in the flow in bleed channel cavities in the core duct of the PS-90A engine are found to be in reasonable agreement. As a result, various types of resonance oscillations in bleed channels can be accurately described.

  19. In situ secondary organic aerosol formation from ambient pine forest air using an oxidation flow reactor

    NASA Astrophysics Data System (ADS)

    Palm, Brett B.; Campuzano-Jost, Pedro; Ortega, Amber M.; Day, Douglas A.; Kaser, Lisa; Jud, Werner; Karl, Thomas; Hansel, Armin; Hunter, James F.; Cross, Eben S.; Kroll, Jesse H.; Peng, Zhe; Brune, William H.; Jimenez, Jose L.

    2016-03-01

    An oxidation flow reactor (OFR) is a vessel inside which the concentration of a chosen oxidant can be increased for the purpose of studying SOA formation and aging by that oxidant. During the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen-Rocky Mountain Biogenic Aerosol Study) field campaign, ambient pine forest air was oxidized by OH radicals in an OFR to measure the amount of SOA that could be formed from the real mix of ambient SOA precursor gases, and how that amount changed with time as precursors changed. High OH concentrations and short residence times allowed for semicontinuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq.) atmospheric aging. A simple model is derived and used to account for the relative timescales of condensation of low-volatility organic compounds (LVOCs) onto particles; condensational loss to the walls; and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 3 µg m-3 when LVOC fate corrected) compared to daytime (average 0.9 µg m-3 when LVOC fate corrected), with maximum formation observed at 0.4-1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene+p-cymene concentrations, including a substantial increase just after sunrise at 07:00 local time. Higher photochemical aging (> 10 eq. days) led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254-70), similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production of small oxidized organic

  20. In situ secondary organic aerosol formation from ambient pine forest air using an oxidation flow reactor

    DOE PAGES

    Palm, Brett B.; Campuzano-Jost, Pedro; Ortega, Amber M.; ...

    2016-03-08

    An oxidation flow reactor (OFR) is a vessel inside which the concentration of a chosen oxidant can be increased for the purpose of studying SOA formation and aging by that oxidant. During the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen–Rocky Mountain Biogenic Aerosol Study) field campaign, ambient pine forest air was oxidized by OH radicals in an OFR to measure the amount of SOA that could be formed from the real mix of ambient SOA precursor gases, and how that amount changed with time as precursors changed. High OH concentrations and short residence times allowed formore » semicontinuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq.) atmospheric aging. A simple model is derived and used to account for the relative timescales of condensation of low-volatility organic compounds (LVOCs) onto particles; condensational loss to the walls; and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 3 µg m−3 when LVOC fate corrected) compared to daytime (average 0.9 µg m−3 when LVOC fate corrected), with maximum formation observed at 0.4–1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene+p-cymene concentrations, including a substantial increase just after sunrise at 07:00 local time. Higher photochemical aging (> 10 eq. days) led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254-70), similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production of

  1. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how to... associated examples are contained in the “Guideline for Interpretation of Ozone Air Quality Standards.”...

  2. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how to... associated examples are contained in the “Guideline for Interpretation of Ozone Air Quality Standards.”...

  3. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how to... associated examples are contained in the “Guideline for Interpretation of Ozone Air Quality Standards.”...

  4. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how to... associated examples are contained in the “Guideline for Interpretation of Ozone Air Quality Standards.”...

  5. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how to... associated examples are contained in the “Guideline for Interpretation of Ozone Air Quality Standards.”...

  6. Effects of ambient air pollution on respiratory tract complaints and airway inflammation in primary school children.

    PubMed

    Altuğ, Hicran; Gaga, Eftade O; Döğeroğlu, Tuncay; Brunekreef, Bert; Hoek, Gerard; Van Doorn, Wim

    2014-05-01

    Respiratory health effects of ambient air pollution were studied in 605 school children 9 to 13 years in Eskişehir, Turkey. Each child performed a fractional exhaled nitric oxide (FENO) measurement and a lung function test (LFT). Self-reported respiratory tract complaints (having cold, complaints of throat, runny nose and shortness of breath/wheezing) in the last 7 days and on the day of testing were also recorded. As acute health outcomes were investigated, weekly average ambient concentrations of ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2) were determined by passive sampling in the school playgrounds simultaneously with the health survey. Effects of air pollution on respiratory tract complaints and exhaled NO/lung function were estimated by multivariate logistic regression and multivariate linear mixed effects models, respectively. Upper respiratory tract complaints were significantly (p<0.05) associated with weekly average O3 concentrations during the health survey (adjusted odds ratios (OR) of 1.21 and 1.28 for a 10 μgm(-3) increment for having cold and a runny nose on day of testing, respectively). FENO levels were significantly (p<0.05) increased in children with various upper respiratory tract complaints (ratio in FENO varied between 1.16 and 1.40). No significant change in FENO levels was detected in association with any of the measured pollutants (p ≥ 0.05). Lung function was not associated with upper respiratory tract complaints and FENO levels. Peak Expiratory Flow (PEF) levels were negatively associated with weekly average O3 levels for children without upper respiratory tract complaints. In summary, elevated levels of air pollutants increased respiratory tract complaints in children.

  7. Oxidative potential and inflammatory impacts of source apportioned ambient air pollution in Beijing.

    PubMed

    Liu, Qingyang; Baumgartner, Jill; Zhang, Yuanxun; Liu, Yanju; Sun, Yongjun; Zhang, Meigen

    2014-11-04

    Air pollution exposure is associated with a range of adverse health impacts. Knowledge of the chemical components and sources of air pollution most responsible for these health effects could lead to an improved understanding of the mechanisms of such effects and more targeted risk reduction strategies. We measured daily ambient fine particulate matter (<2.5 μm in aerodynamic diameter; PM2.5) for 2 months in peri-urban and central Beijing, and assessed the contribution of its chemical components to the oxidative potential of ambient air pollution using the dithiothreitol (DTT) assay. The composition data were applied to a multivariate source apportionment model to determine the PM contributions of six sources or factors: a zinc factor, an aluminum factor, a lead point factor, a secondary source (e.g., SO4(2-), NO3(2-)), an iron source, and a soil dust source. Finally, we assessed the relationship between reactive oxygen species (ROS) activity-related PM sources and inflammatory responses in human bronchial epithelial cells. In peri-urban Beijing, the soil dust source accounted for the largest fraction (47%) of measured ROS variability. In central Beijing, a secondary source explained the greatest fraction (29%) of measured ROS variability. The ROS activities of PM collected in central Beijing were exponentially associated with in vivo inflammatory responses in epithelial cells (R2=0.65-0.89). We also observed a high correlation between three ROS-related PM sources (a lead point factor, a zinc factor, and a secondary source) and expression of an inflammatory marker (r=0.45-0.80). Our results suggest large differences in the contribution of different PM sources to ROS variability at the central versus peri-urban study sites in Beijing and that secondary sources may play an important role in PM2.5-related oxidative potential and inflammatory health impacts.

  8. The deployment of carbon monoxide wireless sensor network (CO-WSN) for ambient air monitoring.

    PubMed

    Chaiwatpongsakorn, Chaichana; Lu, Mingming; Keener, Tim C; Khang, Soon-Jai

    2014-06-16

    Wireless sensor networks are becoming increasingly important as an alternative solution for environment monitoring because they can reduce cost and complexity. Also, they can improve reliability and data availability in places where traditional monitoring methods are difficult to site. In this study, a carbon monoxide wireless sensor network (CO-WSN) was developed to measure carbon monoxide concentrations at a major traffic intersection near the University of Cincinnati main campus. The system has been deployed over two weeks during Fall 2010, and Summer 2011-2012, traffic data was also recorded by using a manual traffic counter and a video camcorder to characterize vehicles at the intersection 24 h, particularly, during the morning and evening peak hour periods. According to the field test results, the 1 hr-average CO concentrations were found to range from 0.1-1.0 ppm which is lower than the National Ambient Air Quality Standards (NAAQS) 35 ppm on a one-hour averaging period. During rush hour periods, the traffic volume at the intersection varied from 2,067 to 3,076 vehicles per hour with 97% being passenger vehicles. Furthermore, the traffic volume based on a 1-h average showed good correlation (R2 = 0.87) with the 1-h average CO-WSN concentrations for morning and evening peak time periods whereas CO-WSN results provided a moderate correlation (R2 = 0.42) with 24 hours traffic volume due to fluctuated changes of meteorological conditions. It is concluded that the performance and the reliability of wireless ambient air monitoring networks can be used as an alternative method for real time air monitoring.

  9. Short term respiratory health effects of ambient air pollution: results of the APHEA project in Paris.

    PubMed Central

    Dab, W; Medina, S; Quénel, P; Le Moullec, Y; Le Tertre, A; Thelot, B; Monteil, C; Lameloise, P; Pirard, P; Momas, I; Ferry, R; Festy, B

    1996-01-01

    STUDY OBJECTIVE: To quantify the short term respiratory health effects of ambient air pollution in the Paris area. DESIGN: Time series analysis of daily pollution levels using Poisson regression. SETTING: Paris, 1987-92. MEASUREMENTS AND MAIN RESULTS: Air pollution was monitored by measurement of black smoke (BS) (15 monitoring stations), sulphur dioxide (SO2), nitrogen dioxide (NO2), particulate matter less than 13 microns in diameter (PM13), and ozone (O3) (4 stations). Daily mortality and general admissions to public hospitals due to respiratory causes were considered. The statistical analysis was based on a time series procedure using linear regression modelling followed by a Poisson regression. Meterological variables, epidemics of influenza A and B, and strikes of medical staff were included in the models. The mean daily concentration of PM13 and daily 1 hour maximum of SO2 significantly affected daily mortality from respiratory causes. An increase in the concentration of PM13 of 100 micrograms/m3 above its 5th centile value increased the risk of respiratory death by 17%. PM13 and BS were also associated with hospital admissions due to all respiratory diseases (4.1% increased risk when the BS level exceeded its 5th centile value by 100 micrograms/m3). SO2 levels consistently influenced hospital admissions for all respiratory diseases, chronic obstructive pulmonary disease, and asthma. Asthma was also correlated with NO2 levels. CONCLUSIONS: These results indicate that even though the relative risk is weak in areas with low levels of pollution, ambient air pollution, and especially particulate matter and SO2, nonetheless require attention because of the number of people exposed and the existence of high risk groups. PMID:8758223

  10. The Deployment of Carbon Monoxide Wireless Sensor Network (CO-WSN) for Ambient Air Monitoring

    PubMed Central

    Chaiwatpongsakorn, Chaichana; Lu, Mingming; Keener, Tim C.; Khang, Soon-Jai

    2014-01-01

    Wireless sensor networks are becoming increasingly important as an alternative solution for environment monitoring because they can reduce cost and complexity. Also, they can improve reliability and data availability in places where traditional monitoring methods are difficult to site. In this study, a carbon monoxide wireless sensor network (CO-WSN) was developed to measure carbon monoxide concentrations at a major traffic intersection near the University of Cincinnati main campus. The system has been deployed over two weeks during Fall 2010, and Summer 2011–2012, traffic data was also recorded by using a manual traffic counter and a video camcorder to characterize vehicles at the intersection 24 h, particularly, during the morning and evening peak hour periods. According to the field test results, the 1 hr-average CO concentrations were found to range from 0.1–1.0 ppm which is lower than the National Ambient Air Quality Standards (NAAQS) 35 ppm on a one-hour averaging period. During rush hour periods, the traffic volume at the intersection varied from 2,067 to 3,076 vehicles per hour with 97% being passenger vehicles. Furthermore, the traffic volume based on a 1-h average showed good correlation (R2 = 0.87) with the 1-h average CO-WSN concentrations for morning and evening peak time periods whereas CO-WSN results provided a moderate correlation (R2 = 0.42) with 24 hours traffic volume due to fluctuated changes of meteorological conditions. It is concluded that the performance and the reliability of wireless ambient air monitoring networks can be used as an alternative method for real time air monitoring. PMID:24937527

  11. Propulsion Controls, 1979. [air breathing engine control

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The state of the art of multivariable engine control is examined in order to determine future needs and problem areas and to establish the appropriate roles of government, industries, and universities in addressing these problems.

  12. Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Rooftop Air Conditioners

    SciTech Connect

    Abdelaziz, Omar; Shrestha, Som S.; Shen, Bo; Linkous, Randall Lee; Goetzler, William; Guernsey, Matt; Bargach, Youssef

    2016-09-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient-Temperature Evaluation Program for Low-Global Warming Potential (Low-GWP) Refrigerants aims to develop an understanding of the performance of low-GWP alternative refrigerants relative to hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants in packaged or Rooftop Unit (RTU) air conditioners under high-ambient-temperature conditions. This final report describes the parties involved, the alternative refrigerants selection process, the test procedures, and the final results.

  13. Evidence of health impacts of sulfate-and nitrate-containing particles in ambient air.

    PubMed

    Reiss, Richard; Anderson, Elizabeth L; Cross, Carroll E; Hidy, George; Hoel, David; McClellan, Roger; Moolgavkar, Suresh

    2007-05-01

    Ambient particulate matter (PM) is a complex mixture of inorganic and organic compounds. The U.S. Environmental Protection Agency (EPA) regulates PM as a criteria pollutant and promulgates National Ambient Air Quality Standards for it. The PM indicator is based on mass concentration, unspecified as to chemical composition, for specific size fractions. The numerical standards are based on epidemiologic evidence of associations between the various size-related particle mass concentrations as indicators and excess mortality and cardiorespiratory health effects as endpoints. The U.S. National Research Council has stated that more research is needed to differentiate the apparent health effects associated with different particle chemical constituents. Sulfate and nitrate constitute a significant portion of the particle mass in the atmosphere, but are accompanied by similar amounts of carbonaceous material, along with low concentrations of various species, including bioactive organic compounds and redox cycling metals. Extensive animal and human toxicology data show no significant effects for particles consisting only of sulfate and nitrate compounds at levels in excess of ambient air concentrations. A few epidemiologic studies, including both short-term time-series studies and long-term cohort studies, have included the sulfate content of PM as a specific variable in health effect analyses. There are much less data for nitrate. The results from the epidemiologic studies with PM sulfate are inconsistent. A detailed analysis of the time-series epidemiological studies shows that PM sulfate has a weaker "risk factor" than PM2.5 for health effects. Since sulfate is correlated with PM2.5, this result is inconsistent with sulfate having a strong health influence. However, there are many limitations with these types of studies that warrant caution for any comparison between a chemical component and mass concentration. In total, the epidemiologic and toxicologic evidence provide

  14. Spatial correlation in the ambient core noise field of a turbofan engine.

    PubMed

    Miles, Jeffrey Hilton

    2012-06-01

    An acoustic transfer function relating combustion noise and turbine exit noise in the presence of enclosed ambient core noise is investigated using a dynamic system model and an acoustic system model for the particular turbofan engine studied and for a range of operating conditions. Measurements of cross-spectra magnitude and phase between the combustor and turbine exit and auto-spectra at the turbine exit and combustor are used to show the presence of indirect and direct combustion noise over the frequency range of 0-400 Hz. The procedure used evaluates the ratio of direct to indirect combustion noise. The procedure used also evaluates the post-combustion residence time in the combustor which is a factor in the formation of thermal NO(x) and soot in this region. These measurements are masked by the ambient core noise sound field in this frequency range which is observable since the transducers are situated within an acoustic wavelength of one another. An ambient core noise field model based on one and two dimensional spatial correlation functions is used to replicate the spatially correlated response of the pair of transducers. The spatial correlation function increases measured attenuation due to destructive interference and masks the true attenuation of the turbine.

  15. Spatial Correlation in the Ambient Core Noise Field of a Turbofan Engine

    NASA Technical Reports Server (NTRS)

    Miles, Jeffrey Hilton

    2012-01-01

    An acoustic transfer function relating combustion noise and turbine exit noise in the presence of enclosed ambient core noise is investigated using a dynamic system model and an acoustic system model for the particular turbofan engine studied and for a range of operating conditions. Measurements of cross-spectra magnitude and phase between the combustor and turbine exit and auto-spectra at the turbine exit and combustor are used to show the presence of indirect and direct combustion noise over the frequency range of 0 400 Hz. The procedure used evaluates the ratio of direct to indirect combustion noise. The procedure used also evaluates the post-combustion residence time in the combustor which is a factor in the formation of thermal NOx and soot in this region. These measurements are masked by the ambient core noise sound field in this frequency range which is observable since the transducers are situated within an acoustic wavelength of one another. An ambient core noise field model based on one and two dimensional spatial correlation functions is used to replicate the spatially correlated response of the pair of transducers. The spatial correlation function increases measured attenuation due to destructive interference and masks the true attenuation of the turbine.

  16. Polyfluorinated compounds in ambient air from ship- and land-based measurements in northern Germany

    NASA Astrophysics Data System (ADS)

    Dreyer, Annekatrin; Ebinghaus, Ralf

    Neutral volatile and semi-volatile polyfluorinated organic compounds (PFC) and ionic perfluorinated compounds were determined in air samples collected at two sites in the vicinity of Hamburg, Germany, and onboard the German research vessel Atair during a cruise in the German Bight, North Sea, in early November 2007. PUF/XAD-2/PUF cartridges and glass fiber filters as sampling media were applied to collect several fluorotelomer alcohols (FTOH), fluorotelomer acrylates (FTA), perfluoroalkyl sulfonamides (FASA), and perfluoroalkyl sulfonamido ethanols (FASE) in the gas- and particle-phase as well as a set of perfluorinated carboxylates (PFCA) and sulfonates (PFSA) in the particle-phase. This study presents the distribution of PFC in ambient air of the German North Sea and in the vicinity of Hamburg for the first time. Average total PFC concentrations in and around Hamburg (180 pg m -3) were higher than those observed in the German Bight (80 pg m -3). In the German Bight, minimum-maximum gas-phase concentrations of 17-82 pg m -3 for ΣFTOH, 2.6-10 pg m -3 for ΣFTA, 10-15 pg m -3 for ΣFASA, and 2-4.4 pg m -3 for ΣFASE were determined. In the vicinity of Hamburg, minimum-maximum gas-phase concentrations of 32-204 pg m -3 for ΣFTOH, 3-26 pg m -3 for ΣFTA, 3-18 pg m -3 for ΣFASA, and 2-15 pg m -3 for ΣFASE were detected. Concentrations of perfluorinated acids were in the range of 1-11 pg m -3. FTOH clearly dominated the substance spectrum; 8:2 FTOH occurred in maximum proportions. Air mass back trajectories, cluster, and correlation analyses revealed that the air mass origin and thus medium to long range atmospheric transport was the governing parameter for the amount of PFC in ambient air. Southwesterly located source regions seemed to be responsible for elevated PFC concentrations, local sources appeared to be of minor importance.

  17. Ambient air pollution and term birth weight in Texas from 1998 to 2004

    PubMed Central

    Geer, Laura A.; Weedon, Jeremy; Bell, Michelle L.

    2012-01-01

    Previous studies have explored the association between air pollution levels and adverse birth outcomes such as lower birth weight. Existing literature suggests an association, although results across studies are not consistent. Additional research is needed to confirm the effect, investigate the exposure window of importance, and distinguish which pollutants cause harm. We assessed the association between ambient pollutant concentrations and term birth weight for 1,548,904 births in TX from 1998 to 2004. Assignment of prenatal exposure to air pollutants was based on maternal county of residence at the time of delivery. Pollutants examined included particulate matter with aerodynamic diameter ≤10 and ≤2.5 μm (PM10 and PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3). We applied a linear model with birth weight as a continuous variable. The model was adjusted for known risk factors and region. We assessed pollutant effects by trimester to identify biological exposure window of concern, and explored interaction due to race/ethnicity. An interquartile increase in ambient pollutant concentrations of SO2 and O3 was associated with a 4.99-g (95% confidence interval [CI], 1.87–8.11) and 2.72-g (95% CI, 1.11–4.33) decrease in birth weight, respectively. Lower birth weight was associated with exposure to O3 in the first and second trimester, whereas results were not significant for other pollutants by trimester. A positive association was exhibited for PM2.5 in the first trimester. Effects estimates for PM10 and PM2.5 were inconsistent across race/ethnic groups. Current ambient air pollution levels may be increasing the risk of lower birth weight for some pollutants. These risks may be increased for certain racial/ethnic groups. Additional research including consideration of improved methodology is needed to investigate these findings. Future studies should examine the influence of residual confounding. PMID:23210220

  18. Time Evolution of the Wettability of Supported Graphene under Ambient Air Exposure

    PubMed Central

    2016-01-01

    The wettability of graphene is both fundamental and crucial for interfacing in most applications, but a detailed understanding of its time evolution remains elusive. Here we systematically investigate the wettability of metal-supported, chemical vapor deposited graphene films as a function of ambient air exposure time using water and various other test liquids with widely different surface tensions. The wettability of graphene is not constant, but varies with substrate interactions and air exposure time. The substrate interactions affect the initial graphene wettability, where, for instance, water contact angles of ∼85 and ∼61° were measured for Ni and Cu supported graphene, respectively, after just minutes of air exposure. Analysis of the surface free energy components indicates that the substrate interactions strongly influence the Lewis acid–base component of supported graphene, which is considerably weaker for Ni supported graphene than for Cu supported graphene, suggesting that the classical van der Waals interaction theory alone is insufficient to describe the wettability of graphene. For prolonged air exposure, the effect of physisorption of airborne contaminants becomes increasingly dominant, resulting in an increase of water contact angle that follows a universal linear-logarithmic relationship with exposure time, until saturating at a maximum value of 92–98°. The adsorbed contaminants render all supported graphene samples increasingly nonpolar, although their total surface free energy decreases only by 10–16% to about 37–41 mJ/m2. Our finding shows that failure to account for the air exposure time may lead to widely different wettability values and contradicting arguments about the wetting transparency of graphene. PMID:26900413

  19. Retinoblastoma and ambient exposure to air toxics in the perinatal period

    PubMed Central

    Heck, Julia E.; Park, Andrew S.; Qiu, Jiaheng; Cockburn, Myles; Ritz, Beate

    2014-01-01

    We examined ambient exposure to specific air toxics in the perinatal period in relation to retinoblastoma development. Cases were ascertained from California Cancer Registry records of children diagnosed 1990–2007 and matched to California birth certificates. Controls were randomly selected from state birth records for the same time period. We chose 27 air toxics for the present study that had been listed as possible, probable, or established human carcinogens by the International Agency for Research on Cancer. Children (103 cases and 30,601 controls) included in the study lived within 5 miles (~8K) of an air pollution monitor. Using logistic regression analyses, we modeled the risk of retinoblastoma due to air toxics exposure, separately for exposures in pregnancy and the first year of life. With a per interquartile range increase in air toxics exposure, retinoblastoma risk was found to be increased with pregnancy exposure to benzene (OR=1.67, 95%CI 1.06, 2.64) and other toxics which primarily arise from gasoline and diesel combustion: toluene, 1,3 butadiene, ethyl benzene, ortho-xylene, and meta/para-xylene; these 6 toxics were highly correlated. Retinoblastoma risk was also increased with pregnancy exposure to chloroform (OR=1.35, 95%CI 1.07, 1.70), chromium (OR=1.29, 95%CI 1.04, 1.60), para-dichlorobenzene (OR=1.24, 95%CI 1.04, 1.49), nickel (OR=1.48, 95%CI 1.08, 2.01), and in the first year of life, acetaldehyde (OR=1.62, 95%CI 1.06, 2.48). Sources of these agents are discussed. PMID:24280682

  20. The Feasibility of Oil Analysis for Air Force Diesel Engines

    DTIC Science & Technology

    1979-06-01

    period 18 September 1978 to 18 June 1979. The Air F’orce Project Monitor was MrW~ le MaW e, - an rton16h ALC /MMET,’ . Mr. J,P. Cuellar, Jr., of SwRI...insolub les 28 TABLE 5. RELATION OF USED CRANKCASE OIL ANALYSIS TO ENGINE CONDITION OR OPERATION (Cont’d) Contributing Engine Condition Test Result...guidelines for wearmetal and lubricant control limits. 46. Schilling, A. (Chief Engineer, Institut Francais du Petrole ), Automobile Engine Lubrication, 1972

  1. U.S. Air Force Turbine Engine Emission Survey. Volume II. Individual Engine Test Reports.

    DTIC Science & Technology

    1978-08-01

    1» I MI HU III.I11M1,|IHIIPH|I»^^—»^ II 111.11 l|. I I | mi | . I I. I.,.L ENGINE J85 -5 17 ^ ^_._. rr •Wl...AD-AÜbl 665 UNCLASSIFIED SCOTT ENVIRONMENTAL TECHNOLOGY INC PLUMSTEAOVILLE PA F/G 21/5 U.S. AIR FORCE TURBINE ENGINE EMISSION SURVEY...i run’ LEVEL CEEDOTR-7834 U.S. AIR FORCE TURBINE ENGINE EMISSION SURVEY VOL II INDIVIDUAL ENGINE TEST REPORTS v o-< 3 „ fi-^\\^92 ANTHONY F

  2. Risk assessment of butadiene in ambient air; the approach used in the UK.

    PubMed

    Fielder, R J

    1996-10-28

    The UK Committee on Carcinogenicity of Chemicals in Food, Consumer Products and the Environment (COC) and the related Committee on Mutagenicity provided advice on 1,3-butadiene in 1992. This followed detailed consideration of the available mutagenicity, animal carcinogenicity and epidemiology data plus information on toxicokinetics. They concluded that 1,3-butadiene was an in vivo mutagen, a potent genotoxic animal carcinogen and should be regarded as a probable human carcinogen. The Department of Health is not aware of more recent data warranting reconsideration of these conclusions. General advice on setting air quality standards for carcinogenic air pollutants was given by the COC. Although the prudent assumption of the absence of any safe level for genotoxic carcinogens was preferred, a pragmatic approach based essentially on assessment of the exposure at which no increased risk would be detected, plus a safety factor, was considered reasonable for compounds like butadiene where exposure cannot be totally avoided. This approach, plus recognition that it is unadvisable to allow ambient levels of genotoxic carcinogens to rise, is used in the UK. The procedure by which the Department of Environment's Expert Panel on Air Quality Standards recommended a value of 1 ppb for butadiene based on these principles is described.

  3. Ambient Air Pollution Exposure Estimation for the Global Burden of Disease 2013.

    PubMed

    Brauer, Michael; Freedman, Greg; Frostad, Joseph; van Donkelaar, Aaron; Martin, Randall V; Dentener, Frank; van Dingenen, Rita; Estep, Kara; Amini, Heresh; Apte, Joshua S; Balakrishnan, Kalpana; Barregard, Lars; Broday, David; Feigin, Valery; Ghosh, Santu; Hopke, Philip K; Knibbs, Luke D; Kokubo, Yoshihiro; Liu, Yang; Ma, Stefan; Morawska, Lidia; Sangrador, José Luis Texcalac; Shaddick, Gavin; Anderson, H Ross; Vos, Theo; Forouzanfar, Mohammad H; Burnett, Richard T; Cohen, Aaron

    2016-01-05

    Exposure to ambient air pollution is a major risk factor for global disease. Assessment of the impacts of air pollution on population health and evaluation of trends relative to other major risk factors requires regularly updated, accurate, spatially resolved exposure estimates. We combined satellite-based estimates, chemical transport model simulations, and ground measurements from 79 different countries to produce global estimates of annual average fine particle (PM2.5) and ozone concentrations at 0.1° × 0.1° spatial resolution for five-year intervals from 1990 to 2010 and the year 2013. These estimates were applied to assess population-weighted mean concentrations for 1990-2013 for each of 188 countries. In 2013, 87% of the world's population lived in areas exceeding the World Health Organization Air Quality Guideline of 10 μg/m(3) PM2.5 (annual average). Between 1990 and 2013, global population-weighted PM2.5 increased by 20.4% driven by trends in South Asia, Southeast Asia, and China. Decreases in population-weighted mean concentrations of PM2.5 were evident in most high income countries. Population-weighted mean concentrations of ozone increased globally by 8.9% from 1990-2013 with increases in most countries-except for modest decreases in North America, parts of Europe, and several countries in Southeast Asia.

  4. Evaluation of the causal framework used for setting national ambient air quality standards.

    PubMed

    Goodman, Julie E; Prueitt, Robyn L; Sax, Sonja N; Bailey, Lisa A; Rhomberg, Lorenz R

    2013-11-01

    Abstract A scientifically sound assessment of the potential hazards associated with a substance requires a systematic, objective and transparent evaluation of the weight of evidence (WoE) for causality of health effects. We critically evaluated the current WoE framework for causal determination used in the United States Environmental Protection Agency's (EPA's) assessments of the scientific data on air pollutants for the National Ambient Air Quality Standards (NAAQS) review process, including its methods for literature searches; study selection, evaluation and integration; and causal judgments. The causal framework used in recent NAAQS evaluations has many valuable features, but it could be more explicit in some cases, and some features are missing that should be included in every WoE evaluation. Because of this, it has not always been applied consistently in evaluations of causality, leading to conclusions that are not always supported by the overall WoE, as we demonstrate using EPA's ozone Integrated Science Assessment as a case study. We propose additions to the NAAQS causal framework based on best practices gleaned from a previously conducted survey of available WoE frameworks. A revision of the NAAQS causal framework so that it more closely aligns with these best practices and the full and consistent application of the framework will improve future assessments of the potential health effects of criteria air pollutants by making the assessments more thorough, transparent, and scientifically sound.

  5. Evolution of porous silicon crystal structure during storage in ambient air

    NASA Astrophysics Data System (ADS)

    Sorokin, L. M.; Ratnikov, V. V.; Kalmykov, A. E.; Sokolov, V. I.

    2010-02-01

    Both double- and triple- crystal X-ray diffraction techniques (X-ray DCD and TCD techniques) together with transmission electron microscopy (TEM) were employed for the investigation of structural changes in porous silicon (PS) layers during prolonged periods (up to 6800 hours) of their storage in ambient air. Apart from the Bragg reflection from the Si substrate, the diffraction pattern contains an additional maximum caused by the presence of the PS layer with an increased lattice parameter. The position of this peak shifts to smaller Bragg angles and its intensity decreases as the time of storage in air increases. In addition, the profiles of such peaks become clearly asymmetric. In this case, Gaussian curves were used to reach a fit to the experimental X-ray rocking curves. All samples were biaxially bent due to compressive stresses that arise as soon as 10 min after electrochemical process. The values of lattice strains along the surface normal (Δd/d)⊥ and lateral deformation (Δd/d)|| were estimated to be ~ +10-3, ~ -10-5 respectively. The analysis of diffraction curve evolution shows a gradual destruction of the crystal lattice caused by the air oxidation process.

  6. Chemical reactivities of ambient air samples in three Southern California communities

    PubMed Central

    Eiguren-Fernandez, Arantza; Di Stefano, Emma; Schmitz, Debra A.; Guarieiro, Aline Lefol Nani; Salinas, Erika M.; Nasser, Elina; Froines, John R.; Cho, Arthur K.

    2015-01-01

    The potential adverse health effects of PM2.5 and vapor samples from three communities that neighbor railyards, Commerce (CM), Long Beach (LB), and San Bernardino (SB), were assessed by determination of chemical reactivities attributed to the induction of oxidative stress by air pollutants. The assays used were dithiothreitol (DTT) and dihydrobenzoic acid (DHBA) based procedures for prooxidant content and a glyceraldehyde-3-phosphate dehydrogenase (GAPDH) assay for electrophiles. Prooxidants and electrophiles have been proposed as the reactive chemical species responsible for the induction of oxidative stress by air pollution mixtures. The PM2.5 samples from CM and LB sites showed seasonal differences in reactivities with higher levels in the winter whereas the SB sample differences were reversed. The reactivities in the vapor samples were all very similar, except for the summer SB samples, which contained higher levels of both prooxidants and electrophiles. The results suggest the observed reactivities reflect general geographical differences rather than direct effects of the railyards. Distributional differences in reactivities were also observed with PM2.5 fractions containing most of the prooxidants (74–81%) and the vapor phase most of the electrophiles (82–96%). The high levels of the vapor phase electrophiles and their potential for adverse biological effects point out the importance of the vapor phase in assessing the potential health effects of ambient air. PMID:25947123

  7. Interaction of Ambient Air Pollution With Asthma Medication on Exhaled Nitric Oxide Among Asthmatics

    PubMed Central

    Qian, Zhengmin; Lin, Hung-Mo; Chinchilli, Vernon M.; Lehman, Erik B.; Duan, Yinkang; Craig, Timothy J.; Wilson, William E.; Liao, Duanping; Lazarus, Stephen C.; Bascom, Rebecca

    2013-01-01

    The interaction between ambient air pollution and asthma medication remains unclear. The authors compared airway inflammation response to air pollution among asthmatics. Increases of 10 ppb of nitrogen dioxide (NO2) and of 10 μg/m3 of particulate matter < 10 micron in diameter (PM10) daily concentrations were associated with an increase in exhaled nitric oxide (eNO) of 0.13 ppb (95% confidence interval = 0.06, 0.19) and of 0.07 ppb (95% confidence interval = 0.02, 0.12), respectively, in models adjusted for important covariates. The results show that the medication could not counteract airway inflammation effects of air pollution. Specifically, the patients on triamcinolone decreased the sensitivity to PM10 but increased the sensitivity to NO2. The patients on salmeterol were more vulnerable to both NO2 and PM10. This study indicates that the current pollution levels may still enhance airway inflammation among patients with persistent asthma even when they are on asthma medications. PMID:19864219

  8. Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Pinkel, Benjamin; Ellerbrock, Herman H , Jr

    1939-01-01

    Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures. The cooling air temperature was varied from approximately 80 degrees F. to 230 degrees F. and the carburetor-air temperature from approximately 40 degrees F. to 160 degrees F. Tests were made over a large range of engine speeds, brake mean effective pressures, and pressure drops across the cylinder. The correction factors obtained experimentally are compared with those obtained from the semiempirical equations and a fair agreement is noted.

  9. Ambient Air Pollution and Cardiovascular Malformations in Atlanta, Georgia, 1986–2003

    PubMed Central

    Klein, Mitchel; Correa, Adolfo; Reller, Mark D.; Mahle, William T.; Riehle-Colarusso, Tiffany J.; Botto, Lorenzo D.; Flanders, W. Dana; Mulholland, James A.; Siffel, Csaba; Marcus, Michele; Tolbert, Paige E.

    2009-01-01

    Associations between ambient air pollution levels during weeks 3–7 of pregnancy and risks of cardiovascular malformations were investigated among the cohort of pregnancies reaching at least 20 weeks’ gestation that were conceived during January 1, 1986–March 12, 2003, in Atlanta, Georgia. Surveillance records obtained from the Metropolitan Atlanta Congenital Defects Program, which conducts active, population-based surveillance on this cohort, were reviewed to classify cardiovascular malformations. Ambient 8-hour maximum ozone and 24-hour average carbon monoxide, nitrogen dioxide, particulate matter with an average aerodynamic diameter of <10 μm (PM10), and sulfur dioxide measurements were obtained from centrally located stationary monitors. Temporal associations between these pollutants and daily risks of secundum atrial septal defect, aortic coarctation, hypoplastic left heart syndrome, patent ductus arteriosus, valvar pulmonary stenosis, tetralogy of Fallot, transposition of the great arteries, muscular ventricular septal defect, perimembranous ventricular septal defect, conotruncal defects, left ventricular outflow tract defect, and right ventricular outflow defect were modeled by using Poisson generalized linear models. A statistically significant association was observed between PM10 and patent ductus arteriosus (for an interquartile range increase in PM10 levels, risk ratio = 1.60, 95% confidence interval: 1.11, 2.31). Of the 60 associations examined in the primary analysis, no other significant associations were observed. PMID:19258486

  10. Ambient air pollution and cardiovascular malformations in Atlanta, Georgia, 1986-2003.

    PubMed

    Strickland, Matthew J; Klein, Mitchel; Correa, Adolfo; Reller, Mark D; Mahle, William T; Riehle-Colarusso, Tiffany J; Botto, Lorenzo D; Flanders, W Dana; Mulholland, James A; Siffel, Csaba; Marcus, Michele; Tolbert, Paige E

    2009-04-15

    Associations between ambient air pollution levels during weeks 3-7 of pregnancy and risks of cardiovascular malformations were investigated among the cohort of pregnancies reaching at least 20 weeks' gestation that were conceived during January 1, 1986-March 12, 2003, in Atlanta, Georgia. Surveillance records obtained from the Metropolitan Atlanta Congenital Defects Program, which conducts active, population-based surveillance on this cohort, were reviewed to classify cardiovascular malformations. Ambient 8-hour maximum ozone and 24-hour average carbon monoxide, nitrogen dioxide, particulate matter with an average aerodynamic diameter of <10 microm (PM(10)), and sulfur dioxide measurements were obtained from centrally located stationary monitors. Temporal associations between these pollutants and daily risks of secundum atrial septal defect, aortic coarctation, hypoplastic left heart syndrome, patent ductus arteriosus, valvar pulmonary stenosis, tetralogy of Fallot, transposition of the great arteries, muscular ventricular septal defect, perimembranous ventricular septal defect, conotruncal defects, left ventricular outflow tract defect, and right ventricular outflow defect were modeled by using Poisson generalized linear models. A statistically significant association was observed between PM(10) and patent ductus arteriosus (for an interquartile range increase in PM(10) levels, risk ratio = 1.60, 95% confidence interval: 1.11, 2.31). Of the 60 associations examined in the primary analysis, no other significant associations were observed.

  11. Detection of Coxiella burnetii in Ambient Air after a Large Q Fever Outbreak

    PubMed Central

    de Rooij, Myrna M. T.; Borlée, Floor; Smit, Lidwien A. M.; de Bruin, Arnout; Janse, Ingmar; Heederik, Dick J. J.; Wouters, Inge M.

    2016-01-01

    One of the largest Q fever outbreaks ever occurred in the Netherlands from 2007–2010, with 25 fatalities among 4,026 notified cases. Airborne dispersion of Coxiella burnetii was suspected but not studied extensively at the time. We investigated temporal and spatial variation of Coxiella burnetii in ambient air at residential locations in the most affected area in the Netherlands (the South-East), in the year immediately following the outbreak. One-week average ambient particulate matter < 10 μm samples were collected at eight locations from March till September 2011. Presence of Coxiella burnetii DNA was determined by quantitative polymerase chain reaction. Associations with various spatial and temporal characteristics were analyzed by mixed logistic regression. Coxiella burnetii DNA was detected in 56 out of 202 samples (28%). Airborne Coxiella burnetii presence showed a clear seasonal pattern coinciding with goat kidding. The spatial variation was significantly associated with number of goats on the nearest goat farm weighted by the distance to the farm (OR per IQR: 1.89, CI: 1.31–2.76). We conclude that in the year after a large Q fever outbreak, temporal variation of airborne Coxiella burnetii is suggestive to be associated with goat kidding, and spatial variation with distance to and size of goat farms. Aerosol measurements show to have potential for source identification and attribution of an airborne pathogen, which may also be applicable in early stages of an outbreak. PMID:26991094

  12. Impact of combustion products from Space Shuttle launches on ambient air quality

    NASA Technical Reports Server (NTRS)

    Dumbauld, R. K.; Bowers, J. F.; Cramer, H. E.

    1974-01-01

    The present work describes some multilayer diffusion models and a computer program for these models developed to predict the impact of ground clouds formed during Space Shuttle launches on ambient air quality. The diffusion models are based on the Gaussian plume equation for an instantaneous volume source. Cloud growth is estimated on the basis of measurable meteorological parameters: standard deviation of the wind azimuth angle, standard deviation of wind elevation angle, vertical wind-speed shear, vertical wind-direction shear, and depth of the surface mixing layer. Calculations using these models indicate that Space Shuttle launches under a variety of meteorological regimes at Kennedy Space Center and Vandenberg AFB are unlikely to endanger the exposure standards for HCl; similar results have been obtained for CO and Al2O3. However, the possibility that precipitation scavenging of the ground cloud might result in an acidic rain that could damage vegetation has not been investigated.

  13. A stringent comparison of sampling and analysis methods for VOCs in ambient air

    SciTech Connect

    Daughtrey, E.H. Jr.; Oliver, K.D.; Adams, J.R.; Kronmiller, K.G.; Lonneman, W.A.; McClenny, W.A.; Colon, M.

    1999-07-01

    A carefully designed study was conducted during the summer of 1998 to simultaneously collect samples of ambient air by canisters and compare the analysis results to direct sorbent preconcentration results taken at the time of sample collection. A total of 32 1-h sample sets were taken, each composed of a real-time sample analyzed by an autoGC/MS XonTech 930/Varian Saturn 2000 system, and SUMMA and Silco canisters. Hourly total non-methane organic carbon (TNMOC), ozone, and meteorological measurements were also made. Each of the canisters was analyzed on the autoGC/MS system for a target list of 108 VOCs and on a manual cryosampling GC/FID system. Comparisons are made between the collection and analysis methods. Because of the low sample loading (150--250 ppbC TNMOC), these comparisons are a stringent test of sample collection and analysis capabilities.

  14. Phytotoxic risk assessment of ambient air pollution on agricultural crops in Selangor State, Malaysia.

    PubMed

    Ishii, S; Bell, J N B; Marshall, F M

    2007-11-01

    The phytotoxic risk of ambient air pollution to local vegetation was assessed in Selangor State, Malaysia. The AOT40 value was calculated by means of the continuously monitored daily maximum concentration and the local diurnal pattern of O3. Together with minor risks associated with the levels of NO2 and SO2, the study found that the monthly AOT40 values in these peri-urban sites were consistently over 1.0 ppm.h, which is well in exceedance of the given European critical level. Linking the O3 level to actual agricultural crop production in Selangor State also indicated that the extent of yield losses could have ranged from 1.6 to 5.0% (by weight) in 2000. Despite a number of uncertainties, the study showed a simple but useful methodological framework for phytotoxic risk assessment with a limited data set, which could contribute to appropriate policy discussion and countermeasures in countries under similar conditions.

  15. Ambient air quality during wheat and rice crop stubble burning episodes in Patiala

    NASA Astrophysics Data System (ADS)

    Mittal, Susheel K.; Singh, Nirankar; Agarwal, Ravinder; Awasthi, Amit; Gupta, Prabhat K.

    Open crop stubble burning events were observed in and around Patiala city, India. A ground level study was deliberated to analyze the contribution of wheat ( Triticum aestivum) and rice ( Oriza sativa) crop stubble burning practices on concentration levels of aerosol, SO 2 and NO 2 in ambient air at five different sites in and around Patiala city covering agricultural, commercial and residential areas. Aerosols were collected on GMF/A and QMF/A (Whatman) sheets for a 24 h period throughout the year in 2007. Simultaneously, sampling of SO 2 and NO 2 was conducted and results obtained during stubble burning periods were compared to the non-stubble burning periods. Results clearly pointed out a distinct increase in aerosol, SO 2 and NO 2 levels during the crop stubble burning periods.

  16. Cloud partitioning of isocyanic acid (HNCO) and evidence of secondary source of HNCO in ambient air

    NASA Astrophysics Data System (ADS)

    Zhao, R.; Lee, A. K. Y.; Wentzell, J. J. B.; Mcdonald, A. M.; Toom-Sauntry, D.; Leaitch, W. R.; Modini, R. L.; Corrigan, A. L.; Russell, L. M.; Noone, K. J.; Schroder, J. C.; Bertram, A. K.; Hawkins, L. N.; Abbatt, J. P. D.; Liggio, J.

    2014-10-01

    Although isocyanic acid (HNCO) may cause a variety of health issues via protein carbamylation and has been proposed as a key compound in smoke-related health issues, our understanding of the atmospheric sources and fate of this toxic compound is currently incomplete. To address these issues, a field study was conducted at Mount Soledad, La Jolla, CA, to investigate partitioning of HNCO to clouds and fogs using an Acetate Chemical Ionization Mass Spectrometer coupled to a ground-based counterflow virtual impactor. The first field evidence of cloud partitioning of HNCO is presented, demonstrating that HNCO is dissolved in cloudwater more efficiently than expected based on the effective Henry's law solubility. The measurements also indicate evidence for a secondary, photochemical source of HNCO in ambient air at this site.

  17. Synthesis of ammonia directly from air and water at ambient temperature and pressure

    PubMed Central

    Lan, Rong; Irvine, John T. S.; Tao, Shanwen

    2013-01-01

    The N≡N bond (225 kcal mol−1) in dinitrogen is one of the strongest bonds in chemistry therefore artificial synthesis of ammonia under mild conditions is a significant challenge. Based on current knowledge, only bacteria and some plants can synthesise ammonia from air and water at ambient temperature and pressure. Here, for the first time, we report artificial ammonia synthesis bypassing N2 separation and H2 production stages. A maximum ammonia production rate of 1.14 × 10−5 mol m−2 s−1 has been achieved when a voltage of 1.6 V was applied. Potentially this can provide an alternative route for the mass production of the basic chemical ammonia under mild conditions. Considering climate change and the depletion of fossil fuels used for synthesis of ammonia by conventional methods, this is a renewable and sustainable chemical synthesis process for future. PMID:23362454

  18. PAH characteristics and genotoxicity in the ambient air of a petrochemical industry complex

    SciTech Connect

    Tsai, Jiun-Horng; Peng, Being-Hwa; Lee, Ding-Zang; Lee, Ching-Chang

    1995-05-01

    Polycyclic aromatic hydrocarbons (PAHs) samples, at four sampling sites, in the ambient air of petrochemical plants were collected by several PS-1 samplers from October 1993 to July 1994 in a petrochemical complex area located in southern Taiwan. In addition, the genotoxicity of the PAH samples were investigated by the Ames Salmonella/microsomal assay system. The winter/summer ratios of total-PAH composition were 0.60, 1.39, 2.97, and 1.28 for sites A, B, C, and D, respectively. This result implied that wind direction is the most significant parameter affecting the total-PAH composition in these four sampling sites. Sampling sites B, C, and D were located on the downwind side of the petrochemical plant and gave higher total-PAH composition than those of sampling site A. Particle phase PAHs had higher mutagenicity than those in the gas phase.

  19. Synthesis of ammonia directly from air and water at ambient temperature and pressure.

    PubMed

    Lan, Rong; Irvine, John T S; Tao, Shanwen

    2013-01-01

    The N≡N bond (225 kcal mol⁻¹) in dinitrogen is one of the strongest bonds in chemistry therefore artificial synthesis of ammonia under mild conditions is a significant challenge. Based on current knowledge, only bacteria and some plants can synthesise ammonia from air and water at ambient temperature and pressure. Here, for the first time, we report artificial ammonia synthesis bypassing N₂ separation and H₂ production stages. A maximum ammonia production rate of 1.14 × 10⁻⁵ mol m⁻² s⁻¹ has been achieved when a voltage of 1.6 V was applied. Potentially this can provide an alternative route for the mass production of the basic chemical ammonia under mild conditions. Considering climate change and the depletion of fossil fuels used for synthesis of ammonia by conventional methods, this is a renewable and sustainable chemical synthesis process for future.

  20. Assessing the impact of the forthcoming decrease in diesel exhaust particulate matter emissions on air quality: implications for black carbon concentrations in ambient air

    NASA Astrophysics Data System (ADS)

    González, Y.; Rodríguez, S.; Cuevas, E.; Ramos, R.; Abreu-Afonso, J.; Baldasano, J. M.

    2009-04-01

    Forthcoming regulations (e.g. EURO 5 and EURO 6) are planned to reduce particulate matter emissions (PM) in the exhaust of forthcoming vehicles. In this study we assess the impact of such reduction in the diesel PM exhaust emissions on the urban ambient air PM concentrations. This has been done by studying the relationship between black carbon (BC) and carbon monoxide (CO) in urban ambient air and in the exhaust of current and forthcoming vehicles. The slope of the BC-vs-CO linear relationship is mainly affected by the percentage (%) of diesel automobiles in the urban vehicles fleet. This slope is a better indicator of the diesel PM emissions than bulk BC concentrations in urban ambient air. BC-vs-CO slopes within the range 1-3 and 7-14 ngBC/µgCO are typically observed in urban areas with low (<25%) and high (≥50%) proportions of diesel-fuel consumption for on road transportation, respectively. The entry into force of forthcoming regulations will decrease the BC-vs-CO slope in urban ambient air from about 10 to 5 ngBC/µgCO in the next decade, according to calculations based on the current data on diesel vehicles in urban fleets in Spanish cities. However, this will not necessary prompt a significant decrease in the urban BC concentrations if road traffic volume follows the increasing trend of the last decade. The results of this study shows that the analysis of the BC-vs-CO slope trend in ambient air is an useful tool for understanding the involvement "of the changes in the vehicle exhaust emissions rates" and "of the changes in the road traffic volume" in the BC and PMx trends in urban ambient air.