581 research outputs found

    Air Pollutant Emissions from Confined Animal Buildings (APECAB) Project: Indiana Data

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    To address the need for gas, odor, and particulate matter (PM) emission from animal production buildings, funding was secured in the fall of 2001 by a six-state research team for a USDA project entitled Air Pollutants Emissions from Confined Animal Buildings, or APECAB. The main objective of the APECAB project was to quantify long-term (yearly) air pollutant emissions from confined animal buildings and establish methodologies for real time measurement of these emissions and build a database of air emissions for US livestock and poultry buildings. The APECAB study was a collaboration of land-grant universities in Minnesota (lead institution), Indiana, Illinois, Texas, Iowa, and North Carolina. Extensive planning occurred during the first nine months for protocol development and equipment selection and purchase. Data collection began at various times during the fall of 2002 for each of the cooperating universities and ended at various times in 2004. The immediate goal of the study was a 15-month sampling period to assure that long-term emissions from actual animal production buildings were determined. Long-term measurements revealed the variations in air emissions due to seasonal effects, animal growth cycles, diurnal variations, and manure handling systems

    Air Pollutant Emissions from Confined Animal Buildings (APECAB) Project: Minnesota Data

    Get PDF
    To address the need for gas, odor, and particulate matter (PM) emission from animal production buildings, funding was secured in the fall of 2001 by a six-state research team for a USDA project entitled Air Pollutants Emissions from Confined Animal Buildings, or APECAB. The main objective of the APECAB project was to quantify long-term (yearly) air pollutant emissions from confined animal buildings and establish methodologies for real time measurement of these emissions and build a database of air emissions for US livestock and poultry buildings. The APECAB study was a collaboration of land-grant universities in Minnesota (lead institution), Indiana, Illinois, Texas, Iowa, and North Carolina. Extensive planning occurred during the first nine months for protocol development and equipment selection and purchase. Data collection began at various times during the fall of 2002 for each of the cooperating universities and ended at various times in 2004. The immediate goal of the study was a 15-month sampling period to assure that long-term emissions from actual animal production buildings were determined. Long-term measurements revealed the variations in air emissions due to seasonal effects, animal growth cycles, diurnal variations, and manure handling systems

    Air Pollutant Emissions from Confined Animal Buildings (APECAB) Project: Iowa Data

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    To address the need for gas, odor, and particulate matter (PM) emission from animal production buildings, funding was secured in the fall of 2001 by a six-state research team for a USDA project entitled Air Pollutants Emissions from Confined Animal Buildings, or APECAB. The main objective of the APECAB project was to quantify long-term (yearly) air pollutant emissions from confined animal buildings and establish methodologies for real time measurement of these emissions and build a database of air emissions for US livestock and poultry buildings. The APECAB study was a collaboration of land-grant universities in Minnesota (lead institution), Indiana, Illinois, Texas, Iowa, and North Carolina. Extensive planning occurred during the first nine months for protocol development and equipment selection and purchase. Data collection began at various times during the fall of 2002 for each of the cooperating universities and ended at various times in 2004. The immediate goal of the study was a 15-month sampling period to assure that long-term emissions from actual animal production buildings were determined. Long-term measurements revealed the variations in air emissions due to seasonal effects, animal growth cycles, diurnal variations, and manure handling systems

    Quality Assured Measurements of Animal Building Emissions: Odor Concentrations

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    Standard protocols for sampling and measuring odor emissions from livestock buildings are needed to guide scientists, consultants, regulators, and policy-makers. A federally funded, multistate project has conducted field studies in six states to measure emissions of odor, coarse particulate matter (PM10), total suspended particulates, hydrogen sulfide, ammonia, and carbon dioxide from swine and poultry production buildings. The focus of this paper is on the intermittent measurement of odor concentrations at nearly identical pairs of buildings in each state and on protocols to minimize variations in these measurements. Air was collected from pig and poultry barns in small (10 L) Tedlar bags through a gas sampling system located in an instrument trailer housing gas and dust analyzers. The samples were analyzed within 30 hr by a dynamic dilution forced-choice olfactometer (a dilution apparatus). The olfactometers (AC’SCENT International Olfactometer, St. Croix Sensory, Inc.) used by all participating laboratories meet the olfactometry standards (American Society for Testing and Materials and European Committee for Standardization [CEN]) in the United States and Europe. Trained panelists (four to eight) at each laboratory measured odor concentrations (dilution to thresholds [DT]) from the bag samples. Odor emissions were calculated by multiplying odor concentration differences between inlet and outlet air by standardized (20 °C and 1 atm) building airflow rates

    Quality-Assured Measurements of Animal Building Emissions: Particulate Matter Concentrations

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    Federally funded, multistate field studies were initiated in 2002 to measure emissions of particulate matter (PM) \u3c10 μm (PM10) and total suspended particulate (TSP), ammonia, hydrogen sulfide, carbon dioxide, methane, non-methane hydrocarbons, and odor from swine and poultry production buildings in the United States. This paper describes the use of a continuous PM analyzer based on the tapered element oscillating microbalance (TEOM). In these studies, the TEOM was used to measure PM emissions at identical locations in paired barns. Measuring PM concentrations in swine and poultry barns, compared with measuring PM in ambient air, required more frequent maintenance of the TEOM. External screens were used to prevent rapid plugging of the insect screen in the PM10 preseparator inlet. Minute means of mass concentrations exhibited a sinusoidal pattern that followed the variation of relative humidity, indicating that mass concentration measurements were affected by water vapor condensation onto and evaporation of moisture from the TEOM filter. Filter loading increased the humidity effect, most likely because of increased water vapor adsorption capacity of added PM. In a single layer barn study, collocated TEOMs, equipped with TSP and PM10 inlets, corresponded well when placed near the inlets of exhaust fans in a layer barn. Initial data showed that average daily mean concentrations of TSP, PM10, and PM2.5concentrations at a layer barn were 1440 ± 182 μg/m3 (n = 2), 553 ± 79 μg/m3 (n = 4), and 33 ± 75 μg/m3 (n = 1), respectively. The daily mean TSP concentration (n =1) of a swine barn sprinkled with soybean oil was 67% lower than an untreated swine barn, which had a daily mean TSP concentration of 1143 ± 619 μg/m3. The daily mean ambient TSP concentration (n = 1) near the swine barns was 25 ± 8 μg/m3. Concentrations of PM inside the swine barns were correlated to pig activity

    Real-Time Ventilation Measurements from Mechanically Ventilated Livestock Buildings for Emission Rate Estimations

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    A six-state USDA-IFAFS funded research project (Aerial Pollutant Emissions from Confined Animal Buildings, APECAB) was conducted with the purpose of determining hydrogen sulfide, ammonia, PM10, and odor emission rates from selected swine and poultry housing systems. An important aspect of emission studies is to be able to measure the mass flow rate of air through the housing system. For this research project, the decision was made to study only fan ventilated buildings due to the difficulty in estimating mass flow rates through naturally ventilated buildings. This paper highlights the various techniques used throughout the study to determine mass flow rate through fan ventilated swine and poultry housing systems

    Mass hierarchy, mass gap and corrections to Newton's law on thick branes with Poincare symmetry

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    We consider a scalar thick brane configuration arising in a 5D theory of gravity coupled to a self-interacting scalar field in a Riemannian manifold. We start from known classical solutions of the corresponding field equations and elaborate on the physics of the transverse traceless modes of linear fluctuations of the classical background, which obey a Schroedinger-like equation. We further consider two special cases in which this equation can be solved analytically for any massive mode with m^2>0, in contrast with numerical approaches, allowing us to study in closed form the massive spectrum of Kaluza-Klein (KK) excitations and to compute the corrections to Newton's law in the thin brane limit. In the first case we consider a solution with a mass gap in the spectrum of KK fluctuations with two bound states - the massless 4D graviton free of tachyonic instabilities and a massive KK excitation - as well as a tower of continuous massive KK modes which obey a Legendre equation. The mass gap is defined by the inverse of the brane thickness, allowing us to get rid of the potentially dangerous multiplicity of arbitrarily light KK modes. It is shown that due to this lucky circumstance, the solution of the mass hierarchy problem is much simpler and transparent than in the (thin) Randall-Sundrum (RS) two-brane configuration. In the second case we present a smooth version of the RS model with a single massless bound state, which accounts for the 4D graviton, and a sector of continuous fluctuation modes with no mass gap, which obey a confluent Heun equation in the Ince limit. (The latter seems to have physical applications for the first time within braneworld models). For this solution the mass hierarchy problem is solved as in the Lykken-Randall model and the model is completely free of naked singularities.Comment: 25 pages in latex, no figures, content changed, corrections to Newton's law included for smooth version of RS model and an author adde
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