We estimate regionally resolved methane (CH4) emissions for California by comparing CH4 mixing ratios measured at a network of measurement sites in the Central Valley with transport model predictions based on two independent emission maps: a 0.1 degree seasonally varying 'California-specific' emission map, calibrated to state-wide by CH4 emission totals, and the 0.1 degree global EDGAR42 CH4 emission map. Atmospheric particle trajectories and surface footprints (sensitivity of CH4 signals to surface emissions) are computed using the Weather Research and Forecasting (WRF) and Stochastic Time-Inverted Lagrangian Transport (STILT) models. Uncertainties due to wind velocity and boundary layer mixing depth are evaluated using measurements from radar wind profilers. Bayesian region analyses of data from the tower network constrains annual average CH4 emissions from Californias Central Valley to between 31.43 + or = 2.07 and 28.27 + or = 2.00 Tg CO2eq (assuming a global warming potential of 21 Tg CO2eq/ Tg CH4) for the California-specific and EDGAR42 emission models respectively, showing consistency between the two independent models. Extrapolating results to annually averaged CH4 emissions across all of California totals 1.44 + or = 0.15 and 1.94 + or = 0.28 times larger than the current inventory estimate for State annual total CH4 emissions (32 Tg CO2eq) for the California-specific CH4 and EDGAR42 CH4 emission maps, respectively. When emissions from large urban areas are estimated based on a recent study in the larger Los Angeles metropolitan region to better constrain urban emissions, State total CH4 emissions are estimated to be 1.30 - 1.74 times larger than the current State total CH4 emissions. These results based on the multiple emission models suggest that the California total of CH4 emissions would account for approximately 8% - 13% of the States total greenhouse gas (GHG) emissions, which is significantly higher than the CARB inventory (approximately 6% of total GHG emissions). Spatial resolution of emissions within the influence region reveal seasonality expected from several biogenic sources, including rice agriculture. We expect that additional tower measurements in urban regions (e.g., South Coast Air Basin) will provide the data necessary for a complete analysis of California's CH4 budget.

关键词：大气；温室气体；空气质量

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Results from 548,507 indoor radon tests from a database compiled by the Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection, Radon Division, are evaluated in this report in an effort to determine areas where concentrations of radon are highest. Indoor radon concentrations were aggregated according to geologic unit and hydrogeologic setting for spatial analysis. Indoor radon concentrations greater than or equal to the U.S. Environmental Protection Agency (USEPA) action level of 4 picocuries per liter (pCi/L) were observed for 39 percent of the test results; the highest concentration was 1,866.4 pCi/L.

关键词：大气；空气污染；空气分析

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Barriers to industrial energy-efficient technologies hinder their use. A number of EPA analyses and industrial experts have found that the utilization of input-based emissions standards (measured in parts-per-million or pounds/MMBtu) in the Clean Air Act creates a regulatory barrier to the installation and deployment of technologies that emit fewer criteria pollutants and use energy more efficiently. Changing emission management strategies to an output-based emissions standard (measured in tons of pollutant emitted) is a way to ameliorate some of these barriers. Combined heat and power (CHP) is one of the key technologies that would see increased industrial application if the emissions standards were modified. Many states have made this change since the EPA first approved it in 2000, although direction from the Federal government could speed implementation modifications.

关键词：大气；能源燃烧；废气排放；空气健康

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The HHE Program evaluated concerns about employees' exposures to pharmaceutical dust at an outpatient pharmacy. Investigators sampled the air for dust and measured particle levels. Samples were analyzed for lactose (a common inactive filler) and active pharmaceutical ingredients; both were found. The use of compressed air to clean automatic dispensing machine canisters released dust into the air. Investigators found that after this activity more than an hour passed before the small particles were no longer in the air. Most of these canisters contained uncoated pharmaceutical tables. On two days, one employee was exposed to lisinopril at levels near or above the manufacturer's exposure limit. HHE Program investigators recommended that the employer develop a list of dusty pharmaceuticals and gather exposure guidelines and toxicity data to determine how to handle these substances. A partially-enclosed local exhaust hood should be installed for cleaning and filling canisters with tablets, as well as other tasks that could release pharmaceutical dust into the air. Investigators recommended that the use of compressed air to clean canisters be discontinued and replaced with the use of a vacuum with a long narrow nozzle. Lactose was found on surfaces throughout the pharmacy. The highest contamination level was on a surface used in refilling canisters before it was cleaned. Higher amounts of lactose were found on work surfaces than on undisturbed areas such as elevated shelving. Investigators recommended that all work surfaces be cleaned with alcohol wipes before breaks and at the end of each workday. Investigators noted that employees did not wear protective clothing or safety glasses in the pharmacy, but some employees did wear nitrile gloves when handling pharmaceuticals. HHE Program investigators encouraged employees to (1) wear nitrile gloves when handling pharmaceuticals, (2) wash their hands before eating, drinking, or using tobacco products, and (3) follow procedures for using and maintaining the local exhaust hood.

关键词：大气；空气污染；空气健康

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Measuring PM Emissions from Aircraft Auxiliary Power Units, Tires, and Brakes presents the results of a comprehensive test program designed to measure particulate matter (PM) emissions from auxiliary power units and from tires and brakes during the landing phase of operations of in-service commercial aircraft. The research results are designed to provide a significant contribution to the characterization of emissions from these sources with the goal of helping airports improve the accuracy of their PM emissions inventories.

关键词：大气；PM排放；空气污染

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Creating transportation infrastructure, which can clean up itself and contaminated air surrounding it, can be a groundbreaking approach in addressing environmental challenges of our time. This project has explored a possibility of depositing coatings on the existing materials to address a feasibility of this approach. More specifically, we have quantified the rates of removal of pollutants from the air by a new generation of coatings, which can be applied on any architectural elements and transportation infrastructure. We have also used indicators synthesized in our lab to demonstrate the self-cleaning properties of these now commercially available coatings. In addition, we have worked with the company pioneering this technology in the US and Europe to scope the new application of this technology. The survey of the existing and future commercial projects has indicated that this technology is already leading to very exciting applications in transportation sector, where concrete, asphalt, steel, glass and masonry surfaces will become green and sustainable interfaces mitigating the environmental and health impacts of transportation. The results obtained in this project have a significant relevance to the USDOT goals, such as development of livable communities by providing an access to environmentally sustainable travel options. Moreover, it has also relevance to another DOT goal focused on environmental sustainability, where self-cleaning properties of the coatings have a potential to improve both energy and water conservation.

关键词：大气；空气治理；空气净化

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We attempted to image atmospheric fluorescence in the short-wave infrared (SWIR) from several radioactive sources. Our detection system was an InGaAs camera, fitted with a 25 mm lens to image the scene. No definitive fluorescence was detected. We also used our system to observe the SWIR emission from a proton beam source and established certain criteria for use as fluorescence diagnostics. For example, we clearly observed an enhancement at 1050 nm relative to 1600 nm, consistent with known emission features of molecular nitrogen and with previously published results. However, even for a high activity cobalt-60 source, our recorded signal was not consistent with these diagnostics. Rather, we hypothesize that the small signal which was recorded may have been due to direct incidence of gamma rays on our detector. Compared with the ultraviolet (UV), the infrared emission is expected to be only 20% as bright. We suggest that to increase the signal to noise in the SWIR may require either a telescope to collect a greater fraction of the emission or to image a more localized source than the gamma emission. Further research should include coincident UV and SWIR observations.

关键词：大气；气候变化；空气治理

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The overall goal of the project was to bridge the gap between our knowledge of small-scale geochemical reaction rates and reaction rates meaningful for modeling transport at core scales. The working hypothesis was that reaction rates, determined from laboratory measurements based upon reactions typically conducted in well mixed batch reactors using pulverized reactive media may be significantly changed in in situ porous media flow due to rock microstructure heterogeneity. Specifically we hypothesized that, generally, reactive mineral surfaces are not uniformly accessible to reactive fluids due to the random deposition of mineral grains and to the variation in flow rates within a pore network. Expected bulk reaction rates would therefore have to be correctly up-scaled to reflect such heterogeneity. The specific objective was to develop a computational tool that integrates existing measurement capabilities with pore-scale network models of fluid flow and reactive transport. The existing measurement capabilities to be integrated consisted of (a) pore space morphology, (b) rock mineralogy, and (c) geochemical reaction rates. The objective was accomplished by: (1) characterizing sedimentary sandstone rock morphology using X-ray computed microtomography, (2) mapping rock mineralogy using back-scattered electron microscopy (BSE), X-ray dispersive spectroscopy (EDX) and CMT, (3) characterizing pore-accessible reactive mineral surface area, and (4) creating network models to model acidic CO(sub 2) saturated brine injection into the sandstone rock samples.

关键词：大气；二氧化碳；温室气体

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Project attempts to develop a synthetic analogue for carbonic anhydrase and incorporate it in a membrane for separation of CO2 from coal power plant flue gas. Conference poster presents result of first 9 months of project progress including concept, basic system architecture and membrane properties target, results of molecular modeling for analogue - CO2 interaction, and next steps of testing analogue resistance to flue gas contaminants.

关键词：大气；气体循环；废气重利用

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High-performance homes require that ventilation energy demands and indoor air quality (IAQ) be simultaneously optimized. Researchers have primarily addressed these two areas independently because of the assumption that their goals have to be mutually exclusive. This assumption is based on the fact that the typical mechanism to reduce the concentration of indoor air pollutants has been dilution through increased ventilation, which causes heating, ventilation and air conditioning (HVAC) units to consume more energy. High-performance homes aim to provide the essential energy end-uses (for example, water heating, refrigeration, space heating, and air conditioning) in an energy efficient manner. Given that IAQ is among these essential energy end-uses, we investigated means to optimize the concentration of indoor air pollutants and ventilation energy demands. To this end, we conducted tests in four houses located in Oak Ridge, TN, that were 11 to 20 months old, energy efficient (i.e., expected to consume 50% less energy than a house built per the 2006 International Residential Code), airtight (i.e., natural ventilation rate approximately 0.02 to 0.2 h -1 ), unoccupied, and unfurnished. Our evaluation consisted of identifying air pollutants of concern in these homes that could generally serve as indicators of IAQ, and conducting field experiments and computer simulations to determine the effectiveness and energy required by various techniques that lessened the concentration of these contaminants.

关键词：大气；室内空气监控；空气健康

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