nitrogen dioxide sampling Articles

  • Change in genotoxicity of wastewater during chlorine dioxide and chlorine disinfections and the influence of ammonia nitrogen

    The effects of chlorine dioxide and chlorine disinfections on the genotoxicity of different biologically treated sewage wastewater samples were studied by umu-test. The experiment results showed that when chlorine dioxide dosage was increased from 0 to 30 mg/L, the genotoxicity of wastewater first decreased rapidly and then tended to be stable, while when the chlorine dosage was increased from 0 ...


    By Springer

  • Ammonium, nitrate, and total nitrogen determination in fly ash

    Fly ash is a by-product of the combustion of pulverized coal and is composed of small particles. The composition of the fly ash may vary considerably, however, all fly ashes contain substantial amounts of silicon dioxide (SiO2), aluminum oxide (Al2O3) and calcium oxide (CaO). Nowadays, air pollution control standards require a separation of flue gas before being released to the atmosphere. Fly ...


    By BÜCHI Labortechnik AG

  • Greenhouse gas fluxes in an eastern corn belt soil: Weather, Nitrogen source, and rotation

    Relative contributions of diverse, managed ecosystems to greenhouse gases are not completely documented. This study was conducted to estimate soil surface fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) as affected by management practices and weather. Gas fluxes were measured by vented, static chambers in Drummer and Raub soil series during two growing seasons. Treatments ...

  • EPA studies identify techniques for critical leak testing prior to soil-vapor sampling

    Researchers at EPA’s National Risk Management Research Laboratory (NRMRL) in Ada, OK, are developing quality assurance (QA) measures for soil-gas and sub-slab sampling methods that help differentiate contaminant vapors due to vapor intrusion from background sources. Recent research focused on measures to identify leakage of ambient air into conventional vapor probes, which can significantly ...

  • Pollution, natural resource and economic growth: an econometric analysis

    Theoretical arguments imply that an inverted U-shaped relationship may be quite plausible. It is still not clear from the empirical literature whether the relationship of income and environmental degradation is linear or inverted U-shaped. This paper utilises a more global representative sample, than previous EKC studies, and re-evaluates the environmental Kuznets curve (EKC) of sulphur dioxide, ...


    By Inderscience Publishers

  • Why measuring the ambient NO2 without conversion?

    Nitrogen oxides NOx are pollutants that may have particular impact in terms of greenhouse gases, acidifying air etc ... issuance increased significantly since 1950 with the massive development of transport and industries. It therefore becomes necessary to provide measures always safer these pollutant gases, and to know the reliability of results. Currently, 60% of emissions of NO and NO2 are ...


    By Environnement S.A

  • Effects of industrial air pollution on the respiratory health of children

    There is growing concern regarding to the possible effects of air pollution on respiratory health of children in Eleme industrial area of Port-Harcourt Nigeria. A total of 250 children were sampled from six primary schools with pre-nursery facilities for a period of 18 months. Subjects were divided into two zones (A and B), monitored and examined on weekly basis. The effects of four criteria ...

  • Feasibility Study of an Express Assessment Protocol for the Indoor Air Quality of Air-conditioned Offices

    It is costly to sample all major toxic pollutants in community air. Sampling should be conducted based on an assessment strategy and monitoring planning. Assessment methods that rely on monitoring some representative pollutants have been proposed variously at different times. In Hong Kong, the Environmental Protection Department (HKEPD) launched an Indoor Air Quality (IAQ) certification scheme to ...


    By SAGE Publications

  • Field Method Comparison between Passive Air Samplers and Continuous Monitors for VOCs and NO2 in El Paso, Texas

    This study evaluates the performance of Model 3300 Ogawa Passive Nitrogen Dioxide (NO2) Samplers and 3M 3520 Organic Vapor Monitors (OVMs) by comparing integrated passive sampling concentrations to averaged hourly NO2 and volatile organic compound (VOC) measurements at two sites in El Paso, TX. Sampling periods were three time intervals (3-day weekend, 4-day weekday, and 7-day weekly) for three ...


    By Ogawa & Company, USA, Inc.

  • Air Separation Plants and the Use of Oxygen Monitors

    Air separation plants are critical for many different industries, from clean energy to manufacturing. Nowadays, cryogenic is the most common type of distillation used to separate air into its component gases - nitrogen, oxygen, and inert gases including helium and argon. If your industry relies on air separation for product development or manufacturing, then knowing how the process works is ...

  • Strategies for the reduction of Legionella in biological treatment systems

    A community-wide outbreak of Legionnaire's disease occurred in Warstein, Germany, in August 2013. The epidemic strain, Legionella pneumophila Serogruppe 1, was isolated from an industrial wastewater stream entering the municipal wastewater treatment plant (WWTP) in Wartein, the WWTP itself, the river Wäster and air/water samples from an industrial cooling system 3 km downstream of the WWTP. ...


    By IWA Publishing

  • How to Determine Aquatic Humic Substances

    Aquatic Humic Substances (AHS) result from the decomposition of plant and animal residues and are found in soil, sediment, and water. They are widespread in nature and are mostly comprised from naturally occurring dissolved organic matter in water. AHSs are an important component in water systems, particularly as they relate to the potential fate of chemicals in the aquatic environment. For ...


  • CERCLA remedial and removal actions at historic waste disposal areas.

    Apache Nitrogen Products, Inc. (ANP) has operated a nitrogen-based fertilizer and explosives manufacturing facility in rural Cochise County since 1921. Using a feedstock of anhydrous ammonia, current manufacturing processes produce nitric acid, solid and liquid ammonium nitrate, and various ammonium nitrate-based fertilizer products for regional mining and agricultural markets. Historically, ...


    By Hargis + Associates Inc

  • What is a Breathing or Respiratory Zone?

    In the past, vehicle exhaust gas detectors have been installed on or near the ceiling. In contrary, Critical Environment Technologies Canada Inc. (CETCI) has always recommended that they be installed in the breathing zone. Recently, Quebec’s regulation has reinforced CETCI’s recommendations. It states that “dusts, gases, fumes, vapours and mists found in the workplace ...

  • Effect of chemical oxidation on the gas sensing properties of multi-walled carbon nanotubes

    The effect of chemical oxidation on the gas sensing properties of multi-walled carbon nanotubes (MWNT) is presented in this paper. The MWNT were chemically oxidised in a mixture of concentrated sulphuric and nitric acids. The oxidation time was varied from 4 h to 12 h. X-ray photoelectron spectroscopy was used to study the effect on the chemical composition of the nanotube surface. The results ...


    By Inderscience Publishers

  • What is an `IAQ Profile`?

    The 'IAQ Profile' is a visual presentation of indoor air quality. PPM Technology's range of IAQ Monitors enable continuous monitoring of Indoor Air Quality; this precisely describes changes in concentration levels of selected air quality parameters over a period of time.  The IAQ Profile provides the knowledgebase and database for improving indoor air quality efficiently and ...


    By PPM Technology

  • Texas Instruments - A Novel Separation Technique for the Analysis of Trace Levels of Atmospheric Contaminants in Inert Semiconductor Process Gases

    A NOVEL SEPARATION TECHNIQUE FOR THE ANALYSIS OF TRACELEVELS OF ATMOSPHERIC CONTAMINANTS IN INERTSEMICONDUCTOR PROCESS GASES J. Scott McWilliams, Alan Johnson, Charlene Long, Jeremiah D. Hogan*Texas Instruments, Inc.Dallas, TX 75265 Low ppb detection limits for contamination in cylinder gases have been achieved with gas chromatography using a modified gas ...


    By Environics, Inc.

  • Cartography for air quality monitoring: the geostatistical approach

    Being able to provide quick and accurate pollutant maps from readings at isolated measurement stations is becoming more important today in light of the European norms on air quality and the public’s demand to be informed. Commonly used algorithms for cartography are quick but their accuracy remains to be determined.Firstly, the choice of method is arbitrary and based on user’s subjective ...


    By Geovariances

  • Least-Cost Approaches to Reducing Acid Emissions

    ' The costs of meeting sulfur emission targets can be high. It is essential, therefore, that countries adopt policies which (a) minimize the net economic and social costs of reducing emissions to the agreed target levels, and (b) maximize the overlap between measures designed to reduce acidifying emissions and those addressing other forms of air pollution. This note discusses alternative ...


    By The World Bank

  • Field test experiments to validate the CEN standard measurement method for PM 2,5

    For air quality across the European Union to be assessed on a consistent basis, Member States need to employ standard measurement techniques and procedures, following Community Directive 96/62/EC on ambient air quality assessment and management [1], and Directive 1999/30/EC (1st EC Air Quality Daughter Directive) [2], which sets the parameters specific to the assessment of particulate matter (and ...


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