412 research outputs found

    Use of Low-Cost Ambient Particulate Sensors in Nablus, Palestine with Application to the Assessment of Regional Dust Storms

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    Few air pollutant studies within the Palestinian territories have been reported in the literature. In March–April and May–June of 2018, three low-cost, locally calibrated particulate monitors (AirU’s) were deployed at different elevations and source areas throughout the city of Nablus in Northern West Bank, Palestine. During each of the three-week periods, high but site-to-site similar particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5) and less than 10 µm (PM10) concentrations were observed. The PM2.5 concentrations at the three sampling locations and during both sampling periods averaged 38.2 ± 3.6 µg/m3, well above the World Health Organization’s (WHO) 24 h guidelines. Likewise, the PM10 concentrations exceeded or were just below the WHO’s 24 h guidelines, averaging 48.5 ± 4.3 µg/m3. During both periods, short episodes were identified in which the particulate levels at all three sites increased substantially (≈2×) above the regional baseline. Air mass back trajectory analyses using U.S. National Oceanic and Atmospheric Administration’s (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model suggested that, during these peak episodes, the arriving air masses spent recent days over desert areas (e.g., the Saharan Desert in North Africa). On days with regionally low PM2.5 concentrations (≈20 µg/m3), back trajectory analysis showed that air masses were directed in from the Mediterranean Sea area. Further, the lower elevation (downtown) site often recorded markedly higher particulate levels than the valley wall sites. This would suggest locally derived particulate sources are significant and may be beneficial in the identification of potential remediation options

    The New Deal, Race, and Home Ownership in the 1920s and 1930s

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    Many federal government housing policies began during the New Deal of the 1930s. Many claim that minorities benefited less from these policies than whites. We estimate the relationships between policies in the 1920s and 1930s and black and white home ownership in farm and nonfarm settings using a pseudo-panel of repeated cross-sections of households in 1920, 1930, and 1940 matched with policy measures in 460 state economic areas. The policies examined include FHA mortgage insurance, HOLC loan refinancing, state mortgage moratoria, farm loan programs, public housing, public works and relief, and payments to farmers to take land out of production.

    Multi Path FTIR Agriculture Air Pollution Measurement System

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    This paper details the design and validation of a Multiple Path OP-FTIR system with elevation and radial scanning ability and demonstrates its capabilities to quantify and monitor gaseous ammonia emitted from agricultural facilities. The OP-FTIR system has a 500 m range (1000 m full path length) and allows 360° radial scan and 45° scan in elevation. To study large scale sources, two or more similar systems may be needed. For comparison purposes, we ran two similar but not identical OP-FTIR systems side-by-side in a controlled lab environment and in a series of field environments. We determined that in a controlled environment, the two systems can attain an NH3 agreement of 1- 3% at concentrations above 500 ppb. Due to the short path length (~10 m) in the lab, 500 ppb was the detection limit of the two systems. Path lengths in a field are much longer, allowing a lower detection limit. Average agreement in the field was 1-6%. This difference in agreement from the laboratory is likely due to the non-homogeneous distribution of the pollutant

    Determination of Particle (PM10 and PM2.5) and Gas-Phase Ammonia (NH3) Emissions from a Deep-Pit Swine Operation Using Arrayed Field Measurements and Inverse Gaussian Plume Modeling

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    The contribution of agricultural emissions of primary (direct) and secondary (precursor) pollutants to air quality is rapidly being recognized as an important fraction of local and regional air pollution budgets. However, a significant uncertainty still exists in the magnitude and rate of these types of emissions, especially under “in field” conditions common within the central and western United States. Described herein are the results of a study conducted at a deep-pit swine production facility in central Iowa. The facility consisted of three separate, parallel barns, each housing around 1,250 pigs with an average weight of approximately 90 pounds per animal. The area around the facility was topographically flat and surrounded by soybean and cornfields. A number of portable PM10/PM2.5 (AirMetrics MiniVol) samplers and passive NH3 (Ogawa Model 3300) samplers were arrayed vertically and horizontally around the three-barn production facility, and data were collected on a daily-averaged basis for approximately three weeks in August and September of 2005. Additionally, a monitoring station was established approximately 40 m to the north of the nearest barn to record the typical suite of meteorological parameters (wind speed, direction, temperature, etc.) for determination of near-source atmospheric advection and dispersion. The AirMetrics samplers were operated with PM2.5 impactor separation heads for approximately the first half of the field study and were then switched to the PM10 heads for the remaining portion of the study. Each AirMetrics sampler was fitted with a conditioned, preweighed Teflon filter and operated at approximately five liters per minute for a time-controlled 23-hour period. Following sampling, the filters were recovered, conditioned, and reweighed at USU’s Utah Water Research Laboratory (UWRL) in Logan, UT for filter catch and ultimate determination of each location’s PM2.5/PM10 mass concentration. The Ogawa passive samplers were co-located and operated for the same time periods with the pre-treated (acid-coated) collection pads recovered after the same 23-hr period and stored appropriately until the final analysis for NH3 concentrations could be performed via ion chromatography at the UWRL facility. Emission estimates were derived via the comparisons of the measured particulate and NH3 concentrations at each sampling location with the concentrations for each receptor (sample) point found via application of the EPA-recommended ISCST3 air dispersion model (Lakes Environmental Software). The comparison of the measured and model predicted NH3 concentrations resulted in a derived NH3 emission rate of 17.22 ± 7.2 g/pig/day. This value is slightly more than two times greater than referenced emission rates; however, the two emission rates are within statistical uncertainty of each other. The analyses for the particulate emissions are as yet incomplete; however, preliminary calculations show PM10 and PM2.5 emission rates of 0.55 and 0.14 g/pig/day, respectively

    Aglite: A 3-Wavelength Lidar System for Quantitative Assessment of Agricultural Air Quality and Whole Facility Emissions

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    Ground based remote sensing technologies such as scanning lidar systems (light detection and ranging) are increasingly being used to characterize ambient aerosols due to key advantages (i.e., wide area of regard (10 km2), fast response time (s-1), high spatial resolution (\u3c10 \u3em) and high sensitivity). Scanning lidar allows for 3D imaging of atmospheric motion and aerosol variability, which can be used to quantitatively evaluate particulate matter (PM) concentrations and emissions. Space Dynamics Laboratory, in conjunction with USDA ARS, has developed and successfully deployed a lidar system called Aglite to characterize PM in diverse settings. Aglite is a portable scanning elastic lidar system with three wavelengths (355, 532, and 1064 nm), 6 m long range bins, and an effective range from 0.5 to 15 km. Filter-based PM samplers, optical particle counters, and various meteorological instruments were deployed to provide environmental and PM conditions for use in the lidar retrieval method. The developed retrieval algorithm extracts aerosol optical parameters, which were constrained by the point measurements, and converts return signals to PM concentrations. Once calibrated, the Aglite system can map the spatial distribution and temporal variation of the PM concentrations. Whole facility or operation-based emission rates were calculated from the lidar PM data with a mass balance approach. Concentration comparisons with upwind and downwind point sensors were made to verify data quality; lidar-derived PM levels were usually in good agreement with point sensor measurements. Comparisons of lidar-based emissions with emissions estimated through other methods using point sensor data generally show good agreement

    Emissions Calculated from Particulate Matter and Gaseous Ammonia Measurements from Commercial Dairy in California, USA

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    Emission rates and factors for particulate matter (PM) and gaseous ammonia (NH3) were estimated from measurements taken at a dairy in June 2008. Concentration measurements were made using both point and remote sensors. Filter-based PM samplers and optical particle counters (OPCs) characterized aerodynamic and optical properties, while a scanning elastic lidar measured particles around the facility. The lidar was calibrated to PM concentration using the point measurements. NH3 concentrations were measured using 23 passive samplers and 2 open-path Fourier transform infrared spectrometers (FTS). Emission rates and factors were estimated through both an inverse modeling technique using AERMOD coupled with measurements and a mass-balance approach applied to lidar PM data. Mean PM emission factors ± 95% confidence interval were 3.8 ± 3.2, 24.8 ± 14.5, and 75.9 ± 33.2 g/d/AU for PM2.5, PM10, and TSP, respectively, from inverse modeling and 1.3 ± 0.2, 15.1 ± 2.2, and 46.4 ± 7.0 g/d/AU for PM2.5, PM10, and TSP, respectively, from lidar data. Average daily NH3 emissions from the pens, liquid manure ponds, and the whole facility were 143.4 ± 162.0, 29.0 ± 74.7, and 172.4 ± 121.4 g/d/AU, respectively, based on the passive sampler data and 190.6 ± 55.8, 16.4 ± 8.4, and 207.1 ± 54.7 g/d/AU, respectively, based on FTS measurements. Liquid manure pond emissions averaged 5.4 ± 13.9 and 3.1 ± 1.6 g/m2/d based on passive sampler and FTS measurements, respectively. The calculated PM10 and NH3 emissions were of similar magnitude as those found in literature. Diurnal emission patterns were observed

    Variations in Particle Composition and Size Distributions in and Around a Deep Pit Swine Operation

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    Agricultural facilities are the source of many types of particles and gases that can exhibit an influence on air quality. Emissions potentially impacting air quality from agricultural sources have become a concern for regulatory agencies such as the United States Department of Agriculture (USDA) and the Environmental Protection Agency (EPA). Particle mass concentration influences from agricultural sources can include both primary particles (direct emissions such as dust) and secondary particles (formed from gaseous precursors such as ammonia)

    Understanding Centenarians' Psychosocial Dynamics and Their Contributions to Health and Quality of Life

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    While it is understood that longevity and health are influenced by complex interactions among biological, psychological, and sociological factors, there is a general lack of understanding on how psychosocial factors impact longevity, health, and quality of life among the oldest old. One of the reasons for this paradox is that the amount of funded research on aging in the US is significantly larger in the biomedical compared to psychosocial domains. The goals of this paper are to highlight recent data to demonstrate the impact of four pertinent psychosocial domains on health and quality of life of the oldest old and supplement recommendations of the 2001 NIA Panel on Longevity for future research. The four domains highlighted in this paper are (1) demographics, life events, and personal history, (2) personality, (3) cognition, and (4) socioeconomic resources and support systems
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