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Control of Metallurgical and mineral dusts and fumes in Los Angeles County, California

Description: Report issued by the U.S. Bureau of Mines discussing metallurgical and mineral fumes and dusts in Los Angeles County, California. Properties of dusts and fumes from different minerals are presented. This report includes tables, maps, illustrations, and photographs.
Date: April 1952
Creator: Allen, Glenn L.; Viets, Floyd H. & McCabe, Louis C.
Partner: UNT Libraries Government Documents Department

Using Biofuel Tracers to Study Alternative Combustion Regimes

Description: Interest in the use of alternative fuels and combustion regimes is increasing as the price of petroleum climbs. The inherently higher efficiency of Diesel engines has led to increased adoption of Diesels in Europe, capturing approximately 40% of the new passenger car market. Unfortunately, lower CO{sub 2} emissions are countered with higher nitrogen oxides (NOx) and particulate matter (PM) emissions, and higher noise. Noise and PM have traditionally been the obstacles toward consumer acceptance of Diesel passenger cars in North America, while NOx (a key component in photochemical smog) has been more of an engineering challenge. Diesels are lean burning (combustion with excess oxygen) and reducing NOx to N2 in an oxygen rich environment is difficult. Adding oxygenated compounds to the fuel helps reduce PM emissions, but relying on fuel alone to reduce PM is unrealistic. Keeping peak combustion temperature below 1700 K prevents NOx formation. Altering the combustion regime to burn at temperatures below the NOx threshold and accept a wide variety of fuels seems like a promising alternative for future engines. Homogeneous Charge Compression Ignition (HCCI) is a possible solution. Fuel and air are well mixed prior to intake into a cylinder (homogeneous charge) and ignition occurs by compression of the fuel-air mixture by the piston. HCCI is rapid and relatively cool, producing little NOx and PM. Unfortunately, it is hard to control since HCCI is initiated by temperature and pressure instead of a spark or direct fuel injection. We investigate biofuel HCCI combustion, and use intrinsically labeled biofuels as tracers of HCCI combustion. Data from tracer experiments are used to validate combustion modeling.
Date: February 14, 2006
Creator: Mack, J H; Flowers, D L; Buchholz, B A & Dibble, R W
Partner: UNT Libraries Government Documents Department

Technical Report on Grant

Description: This research project employed a combination of laboratory, field and modeling activities to explore the fate of reactive species in the atmosphere. Our work focused particularly on the behavior of hydroperoxides and their precursors, hydroperoxy radicals. Initially, we pursed the study of these species to elucidate the role they play in the formation of photochemical smog. In recent years, we have extended our studies to the role of these oxidants in forming aerosol particles, due the potential of the latter to influence climate by changing the radiative properties of the atmosphere.
Date: November 21, 2006
Creator: Weinstein-Lloyd, Judith B.
Partner: UNT Libraries Government Documents Department

7th BOC Priestley Conference. Final technical report, May 1, 1994--April 30, 1995

Description: The 1994 BOC Priestly Conference was held at Bucknell University in Lewisburg, PA, from June 24 through June 27, 1994. This conference, managed by the American Chemical Society (ACS), was a joint celebration with the Royal Society of Chemistry (RSC) commemorating Joseph Priestley`s arrival in the US and his discovery of oxygen. There were 120 attendees. The basic theme of the conference was Oxidants and Oxidation in the Earth`s Atmosphere, with a keynote lecture on the history of ozone. A distinguished group of US and international atmospheric chemists addressed the issues dominating current research and policy agendas. Topics crucial to the atmospheric chemistry of global change and local and regional air pollution were discussed. The program for the conference included four technical sessions on the following topics: Oxidative fate of atmospheric pollutants; Photochemical smog and ozone; Stratospheric ozone; and, Global tropospheric ozone.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

Reducing indoor residential exposures to outdoor pollutants

Description: The basic strategy for providing indoor air quality in residences is to dilute indoor sources with outdoor air. This strategy assumes that the outdoor air does not have pollutants at harmful levels or that the outdoor air is, at least, less polluted than the indoor air. When this is not the case, different strategies need to be employed to ensure adequate air quality in the indoor environment. These strategies include ventilation systems, filtration and other measures. These strategies can be used for several types of outdoor pollution, including smog, particulates and toxic air pollutants. This report reviews the impacts that typical outdoor air pollutants can have on the indoor environment and provides design and operational guidance for mitigating them. Poor quality air cannot be used for diluting indoor contaminants, but more generally it can become an indoor contaminant itself. This paper discusses strategies that use the building as protection against potentially hazardous outdoor pollutants, including widespread pollutants, accidental events, and potential attacks.
Date: July 1, 2003
Creator: Sherman, Max H. & Matson, Nance E.
Partner: UNT Libraries Government Documents Department

Potential impacts of climate change on tropospheric ozone in California: a preliminary episodic modeling assessment of the Los Angeles basin and the Sacramento valley

Description: In this preliminary and relatively short modeling effort, an initial assessment is made for the potential air quality implications of climate change in California. The focus is mainly on the effects of changes in temperature and related meteorological and emission factors on ozone formation. Photochemical modeling is performed for two areas in the state: the Los Angeles Basin and the Sacramento Valley.
Date: January 1, 2001
Creator: Taha, Haider
Partner: UNT Libraries Government Documents Department

Environmental chamber studies of atmospheric reactivities of volatile organic compounds: Effects of varying chamber and light source

Description: Photochemical oxidant models are essential tools for assessing effects of emissions changes on ground-level ozone formation. Such models are needed for predicting the ozone impacts of increased alternative fuel use. The gas-phase photochemical mechanism is an important component of these models because ozone is not emitted directly, but is formed from the gas-phase photochemical reactions of the emitted volatile organic compounds (VOCs) and oxides of nitrogen (NO{sub x}) in air. The chemistry of ground level ozone formation is complex; hundreds of types of VOCs being emitted into the atmosphere, and most of their atmospheric reactions are not completely understood. Because of this, no chemical model can be relied upon to give even approximately accurate predictions unless it has been evaluated by comparing its predictions with experimental data. Therefore an experimental and modeling study was conducted to assess how chemical mechanism evaluations using environmental chamber data are affected by the light source and other chamber characteristics. Xenon arc lights appear to give the best artificial representation of sunlight currently available, and experiments were conducted in a new Teflon chamber constructed using such a light source. Experiments were also conducted in an outdoor Teflon Chamber using new procedures to improve the light characterization, and in Teflon chambers using blacklights. These results, and results of previous runs other chambers, were compared with model predictions using an updated detailed chemical mechanism. The magnitude of the chamber radical source assumed when modeling the previous runs were found to be too high; this has implications in previous mechanism evaluations. Temperature dependencies of chamber effects can explain temperature dependencies in chamber experiments when Ta-300{degree}K, but not at temperatures below that.
Date: May 1, 1995
Creator: Carter, W.; Luo, D.; Malkina, I. & Pierce, J.
Partner: UNT Libraries Government Documents Department

Impacts of cool cities on air quality: A preliminary modeling assessment for Nashville TN, Dallas TX and Atlanta GA

Description: Previous atmospheric modeling efforts that concentrated on the Los Angeles Basin suggested beneficial and significant air quality impacts from cool cities strategies. This paper discusses an extension of similar modeling efforts to three regions, Atlanta GA, Dallas - Ft. Worth TX, and Nashville TN, that experience smog and air quality problems. According to the older ozone air quality standard (120 ppb), these regions were classified as serious, moderate, and marginal, respectively, but may be out of compliance with respect to the newer, 80-ppb/8-hours standard. Results from this exploratory modeling work suggest a range of possible impacts on meteorological and air quality conditions. For example, peak ozone concentrations during each region's respective episode could be decreased by 1-6 ppb (conservative and optimistic scenarios, respectively) in Nashville, 5-15 ppb in Dallas - Fort Worth, and 5-12 ppb in Atlanta following implementation of cool cities. The reductions are generally smaller than those obtained from simulating the Los Angeles Basin but are still significant. In all regions, the simulations suggest, the net, domain-wide effects of cool cities are reductions in ozone mass and improvements in air quality. In Atlanta, Nashville, and Dallas, urban areas benefiting from reduced smog reach up to 8460, 7350, and 12870 km{sup 2} in area, respectively. Results presented in this paper should be taken as exploratory and preliminary. These will most likely change during a more comprehensive modeling study to be started soon with the support of the US Environmental Protection Agency. The main purpose of the present project was to obtain the initial data (emission inventories) for these regions, simulate meteorological conditions, and perform preliminary sensitivity analysis. In the future, additional regions will be simulated to assess the potential of cool cities in improving urban air quality.
Date: June 15, 1998
Creator: Taha, Haider
Partner: UNT Libraries Government Documents Department

A Numerical Investigation into the Anomalous Slight NOx Increase when Burning Biodiesel: A New (Old) Theory

Description: Biodiesel is a notable alternative to petroleum derived diesel fuel because it comes from natural domestic sources and thus reduces dependence on diminishing petroleum fuel from foreign sources, it likely lowers lifecycle greenhouse gas emissions, and it lowers an engine's emission of most pollutants as compared to petroleum derived diesel. However, the use of biodiesel often slightly increases a diesel engine's emission of smog forming nitrogen oxides (NO{sub x}) relative to petroleum diesel. In this paper, previously proposed theories for this slight NOx increase are reviewed, including theories based on biodiesel's cetane number, which leads to differing amounts of charge preheating, and theories based on the fuel's bulk modulus, which affects injection timing. This paper proposes an additional theory for the slight NO{sub x} increase of biodiesel. Biodiesel typically contains more double bonded molecules than petroleum derived diesel. These double bonded molecules have a slightly higher adiabatic flame temperature, which leads to the increase in NOx production for biodiesel. Our theory was verified using numerical simulations to show a NOx increase, due to the double bonded molecules, that is consistent with observation. Further, the details of these numerical simulations show that NOx is predominantly due to the Zeldovich mechanism.
Date: January 30, 2007
Creator: Ban-Weiss, G A; Chen, J Y; Buchholz, B A & Dibble, R W
Partner: UNT Libraries Government Documents Department

Final Technical Report: DE-FG03-01ER63099/DE-FG02-01ER63099

Description: Organic material contributes {approx}20-50% to the total fine aerosol mass at continental mid-latitudes (Saxena and Hildemann, 1996; Murphy et al., 1998; Peterson and Tyler, 2002; Putaud et al., 2004) and as much as 90% in tropical forested areas (Andreae and Crutzen, 1997; Artaxo et al., 2002). Significant amounts of carbonaceous aerosols are also observed in the free troposphere (Heald et al., 2005). A substantial fraction of the organic component of atmospheric particles consists of water-soluble, possibly multifunctional compounds (Saxena and Hildemann, 1996; Kavouras et al., 1998). It is critical that we understand how organic aerosols and their precursors are transformed in the atmosphere and the dependence of the transformation on the chemical and thermodynamic conditions of the ambient environment: (1) to accurately forecast how changing emissions will impact atmospheric organic aerosol concentrations and properties on the regional to global scale, and (2) to relate atmospheric measurements to sources. A large (but as yet unquantified) fraction of organic aerosol is formed in the atmosphere by precursor gases. In addition, both primary and secondary organic aerosol interact with other gas and aerosol species in the atmosphere so that their properties (i.e., size, hygroscopicity, light absorption and scattering sphere efficiency) can change significantly with time and distance from their source. Organic aerosols (OA) are composed of complex mixtures of different organic species from less-polar organics (n-alkanes, polycyclic aromatic hydrocarbons, fatty alcohols, fatty acids, etc.) to highly polar organics such as dicarboxylic acids and multi-functional organic acids. Studies employing FTIR spectroscopy and NEXAFS have demonstrated the presence of different functional groups such as ketonic and carboxylic groups. Humic-like substances (HULIS) have been identified in aerosols. Field observation and laboratory smog chamber studies have demonstrated that oxidative reactions of biogenic and anthropogenic precursors in the gas phase produce low molecular weight organic acids such as ...
Date: February 23, 2005
Creator: Seinfeld, John H.
Partner: UNT Libraries Government Documents Department

An investigation of flow regimes affecting the Mexico City region

Description: The Mexico City region is well-known to the meteorological community for its overwhelming air pollution problem. Several factors contribute to this predicament, namely, the 20 million people and vast amount of industry within the city. The unique geographical setting of the basin encompassing Mexico City also plays an important role. This basin covers approximately 5000 km{sup 2} of the Mexican Plateau at an average elevation of 2250 m above sea level (asl) and is surrounded on three sides by mountains averaging over 3500 m asl, with peaks over 5000 m asl. Only to the north is their a significant opening in the mountainous terrain. Mexico City sprawls over 1000 km{sup 2} in the southwestern portion of the basin. In recent years, several major research programs have been undertaken to investigate the air quality problem within Mexico City. One of these, the Mexico City Air Quality Research Initiative (MARI), conducted in 1990--1993, was a cooperative study between researchers at Los Alamos National Laboratory and the Mexican Petroleum Institute. As part of this study, a field campaign was initiated in February 1991 during which numerous surface, upper air, aircraft, and LIDAR measurements were taken. Much of the work to date has focused upon defining and simulating the local meteorological conditions that are important for understanding the complex photochemistry occurring within the confines of the city. It seems reasonable to postulate, however, that flow systems originating outside of the Mexico City basin will influence conditions within the city much of the time.
Date: May 1, 1995
Creator: Bossert, J.E.
Partner: UNT Libraries Government Documents Department

[News Script: Smog]

Description: Script from the WBAP-TV station in Fort Worth, Texas, covering a news story about the city of Dallas attempting to curb the air pollution issue.
Date: January 26, 1955
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Advanced quadrupole ion trap instrumentation for low level vehicle emissions measurements. CRADA final report for number ORNL93-0238

Description: Quadrupole ion trap mass spectrometry has been evaluated for its potential use in vehicle emissions measurements in vehicle test facilities as an analyzer for the top 15 compounds contributing to smog generation. A variety of ionization methods were explored including ion trap in situ chemical ionization, atmospheric sampling glow discharge ionization, and nitric oxide chemical ionization in a glow discharge ionization source coupled with anion trap mass spectrometer. Emphasis was placed on the determination of hydrocarbons and oxygenated hydrocarbons at parts per million to parts per billion levels. Ion trap in situ water chemical ionization and atmospheric sampling glow discharge ionization were both shown to be amenable to the analysis of arenes, alcohols, aldehydes and, to some degree, alkenes. Atmospheric sampling glow discharge also generated molecular ions of methyl-t-butyl ether (MTBE). Neither of these ionization methods, however, were found to generate diagnostic ions for the alkanes. Nitric oxide chemical ionization, on the other hand, was found to yield diagnostic ions for alkanes, alkenes, arenes, alcohols, aldehydes, and MTBE. The ability to measure a variety of hydrocarbons present at roughly 15 parts per billion at measurement rates of 3 Hz was demonstrated. These results have demonstrated that the ion trap has an excellent combination of sensitivity, specificity, speed, and flexibility with respect to the technical requirements of the top 15 analyzer.
Date: September 1, 1997
Creator: McLuckey, S.A.; Buchanan, M.V.; Asano, K.G.; Hart, K.J.; Goeringer, D.E. & Dearth, M.A.
Partner: UNT Libraries Government Documents Department

ASHRAE and residential ventilation

Description: In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional ...
Date: October 1, 2003
Creator: Sherman, Max H.
Partner: UNT Libraries Government Documents Department

Energy Saving Potentials and Air Quality Benefits of Urban HeatIslandMitigation

Description: Urban areas tend to have higher air temperatures than their rural surroundings as a result of gradual surface modifications that include replacing the natural vegetation with buildings and roads. The term ''Urban Heat Island'' describes this phenomenon. The surfaces of buildings and pavements absorb solar radiation and become extremely hot, which in turn warm the surrounding air. Cities that have been ''paved over'' do not receive the benefit of the natural cooling effect of vegetation. As the air temperature rises, so does the demand for air-conditioning (a/c). This leads to higher emissions from power plants, as well as increased smog formation as a result of warmer temperatures. In the United States, we have found that this increase in air temperature is responsible for 5-10% of urban peak electric demand for a/c use, and as much as 20% of population-weighted smog concentrations in urban areas. Simple ways to cool the cities are the use of reflective surfaces (rooftops and pavements) and planting of urban vegetation. On a large scale, the evapotranspiration from vegetation and increased reflection of incoming solar radiation by reflective surfaces will cool a community a few degrees in the summer. As an example, computer simulations for Los Angeles, CA show that resurfacing about two-third of the pavements and rooftops with reflective surfaces and planting three trees per house can cool down LA by an average of 2-3K. This reduction in air temperature will reduce urban smog exposure in the LA basin by roughly the same amount as removing the basin entire onroad vehicle exhaust. Heat island mitigation is an effective air pollution control strategy, more than paying for itself in cooling energy cost savings. We estimate that the cooling energy savings in U.S. from cool surfaces and shade trees, when fully implemented, is about $5 billion per year ...
Date: August 23, 2005
Creator: Akbari, Hashem
Partner: UNT Libraries Government Documents Department

Cool Colored Roofs to Save Energy and Improve Air Quality

Description: Urban areas tend to have higher air temperatures than their rural surroundings as a result of gradual surface modifications that include replacing the natural vegetation with buildings and roads. The term ''Urban Heat Island'' describes this phenomenon. The surfaces of buildings and pavements absorb solar radiation and become extremely hot, which in turn warm the surrounding air. Cities that have been ''paved over'' do not receive the benefit of the natural cooling effect of vegetation. As the air temperature rises, so does the demand for air-conditioning (a/c). This leads to higher emissions from power plants, as well as increased smog formation as a result of warmer temperatures. In the United States, we have found that this increase in air temperature is responsible for 5-10% of urban peak electric demand for a/c use, and as much as 20% of population-weighted smog concentrations in urban areas. Simple ways to cool the cities are the use of reflective surfaces (rooftops and pavements) and planting of urban vegetation. On a large scale, the evapotranspiration from vegetation and increased reflection of incoming solar radiation by reflective surfaces will cool a community a few degrees in the summer. As an example, computer simulations for Los Angeles, CA show that resurfacing about two-third of the pavements and rooftops with reflective surfaces and planting three trees per house can cool down LA by an average of 2-3K. This reduction in air temperature will reduce urban smog exposure in the LA basin by roughly the same amount as removing the basin entire onroad vehicle exhaust. Heat island mitigation is an effective air pollution control strategy, more than paying for itself in cooling energy cost savings. We estimate that the cooling energy savings in U.S. from cool surfaces and shade trees, when fully implemented, is about $5 billion per year ...
Date: August 23, 2005
Creator: Akbari, Hashem; Levinson, Ronnen; Miller, William & Berdahl, Paul
Partner: UNT Libraries Government Documents Department

[News Clip: Brown Cloud]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6:00 P.M.
Date: November 11, 1986
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Klean air]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 5 P.M.
Date: March 30, 1984
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Elec - legislation]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, covering a news story by reporter Jay Grey about the smog created by vehicles and various plants. Discusses the EPA limitations on plant emissions. The story aired at 10pm.
Date: May 8, 1997
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Studies in chemical reactivity. Progress report, November 30, 1980-1 December 1981

Description: An investigation of the photooxidation of 1,3-dichlorotetralfuoroacetone has been completed, and a manuscript describing the results has been submitted for publication. In this work, measurements of product quantum yields have led to a mechanism for the reaction of CF/sub 2/Cl radicals with O/sub 2/, and have given evidence for the reaction of CF/sub 2/ClO radicals with CO to produce CO/sub 2/. Work has continued on the flash photolysis of 1,3-dichlorotetrafluoroacetone, with emphasis placed on spectroscopic observations of the rate of formation of ClO. An investigation of the flash photolysis of ketene, with detection of products and transient species by time resolved mass spectrometry, is continuing. This investigation seeks information on the kinetics and mechansims CH/sub 2/(/sup 3/B/sub 1/) reactions. An experiment to detect luminescence from CH/sub 2/(/sup 1/B/sub 1/), where CH/sub 2/(/sup 1/B/sub 1/) is produced by pulsed laser photolysis of diazomethane, has been set up. An analysis of a photochemical smog mechanism by variational sensitivity analysis is being done. A preprint on photolysis of 1-iodopropane is included.
Date: January 1, 1981
Creator: Carr, R.W. Jr.
Partner: UNT Libraries Government Documents Department

National impacts on visual air quality from a future energy scenario

Description: A methodology was developed to evaluate impacts on atmospheric visual air quality for nonurban areas caused by regional haze. Estimated values of median visual range for 39 nonurban ambient air quality monitoring sites were shown to have a high correlation with observed values. A decline in median visual range is projected in regions of the west and the Gulf Coast where there is a substantial growth in the combustion of sulfur containing fossil fuels - coal in particular. The projected decline in median visual range in mandatory Class I Federal areas, particularly in the Western US may conflict with Congress's goal of protecting these areas against visibility impairment. Regulations for defining visibility impairment remain to be defined. The meeting of the emission limitations of the state implementation plans is projected to significantly improve the low visibilities experienced in the Eastern US, particularly in the Ohio Valley and the surrounding region.
Date: January 1, 1979
Creator: Nochumson, D.; Wecksung, M. & Gurule, G.
Partner: UNT Libraries Government Documents Department

Air-quality-model update

Description: The Livermore Regional Air Quality Model (LIRAQ) has been updated and improved. This report describes the changes that have been made in chemistry, species treatment, and boundary conditions. The results of smog chamber simulations that were used to verify the chemistry as well as simulations of the entire air quality model for two prototype days in the Bay Area are reported. The results for the prototype day simulations are preliminary due to the need for improvement in meteorology fields, but they show the dependence and sensitivity of high hour ozone to changes in selected boundary and initial conditions.
Date: January 15, 1982
Creator: Penner, J.E. & Walton, J.J.
Partner: UNT Libraries Government Documents Department

The role of geothermal energy in minimizing global environmental problems

Description: Two current global environmental concerns discussed in this paper are the ''greenhouse effect'' and acid rain. Both of these areas have been emphasized by President Bush, and legislation is pending in both state and federal legislatures to address these problems. We need to understand the impact of geothermal energy production in these areas and, from a DOE viewpoint, identify R and D that is critical to meeting existing and pending regulations and laws. 8 refs., 5 figs., 5 tabs.
Date: January 1, 1989
Creator: Traeger, R.K.
Partner: UNT Libraries Government Documents Department