atmospheric diffusion Articles
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The main principles of atmospheric diffusion modelling for regulatory purposes in Russia
This paper discusses the main principles of atmospheric diffusion modelling for regulatory purposes in Russia. They include the choice of air quality criteria, the development of universal models to calculate on a single base the dispersion of atmospheric pollutants from different types of source under unfavourable meteorological and topographical conditions, as well as experimental verification ...
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Applications of regulatory diffusion models in Russia
Russian regulatory diffusion models are based on the concept of worst-case fields of concentration. This concept and its realisation in regulatory models are explained in this article. A worst-case field for this Workshop's EIA Inter-comparison Exercise is given as an example of practical applications of Russian regulatory diffusion models. Model calculations are compared with data from Kincaid, ...
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Marine sediment components: identification and dispersal assessed by diffuse reflectance spectrophotometry
Analysis of deep-sea sediments presents a number of exceptional challenges. Generally, the amount of material available is small and has to be shared among investigators. Also, deep-sea sediment contains a diverse range of components from a variety of sources including lithogenous, biogenous and hydrogenous. Finally, large number of samples is frequently analysed making rapid analysis a ...
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Numerical simulation of the impact of street geometry on vehicle emissions in urban area
Keeping the street geometry acceptable in an urban area has become an important task to improve the air quality. Gaseous emissions from vehicles increase the incidence of a variety of human health problems. This study presents a numerical simulation of the effect of street geometry on the dispersion of vehicular pollutants in an urban area using various types of k-ε turbulence models, i.e., a ...
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Comparison of predictions of the Hybrid Plume Dispersion Model with observations at the Kincaid power plant
The Hybrid Plume Dispersion Model (HPDM) has been evaluated with observations from a field experiment at the Kincaid power plant. HPDM is a dispersion model for buoyant plumes that employs parameterisations of boundary-layer wind, temperature, and turbulence profiles and Lagrangian time-scales. The model accounts for the bimodal distribution of turbulent velocities in the convective boundary ...
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Design methodology for background air pollution monitoring site selection in an urban area
We present an air monitoring site selection procedure to determine the minimum number and location of monitoring stations to identify the occurrence of background concentrations greater than a reference value in an urban area. The objective technique reported here is based on the analysis of concentrations estimated using an urban dispersion model for at least one year of hourly information. As ...
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Contribution of CO2 emitted to the atmosphere by diffuse degassing from volcanoes: The Furnas Volcano case study
Furnas Volcano is a dormant central volcano located in the eastern part of São Miguel Island (Azores archipelago, Portugal). The last volcanic eruption in this volcanic system took place in 1630 causing about 200 victims. Present–day activity comprises fumarolic fields, thermal and cold CO2–rich springs and soil diffuse degassing areas. CO2 diffusely released from the volcano soils was estimated ...
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Validation of an operational advanced Gaussian model with the Copenhagen and Kincaid datasets
A practical model for evaluating ground-level concentrations from elevated sources that applies a new Gaussian formulation for transport and vertical diffusion is presented. In the Gaussian formula, the source height is replaced by a virtual source height, which is expressed by simple functions of the vertical profiles of wind and turbulent diffusivity. The performances of the model are evaluated ...
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On efficient numerical solution of one-dimensional convection?diffusion equations in modelling atmospheric processes
A new approach is proposed to the numerical solution of one-dimensional convection?diffusion equations that arise in modelling atmospheric processes and air pollution modelling. The technique is based on upstream-type difference approximations for first-order derivatives and non-standard difference approximations for second-order derivatives of convection?diffusion equations. This approach leads ...
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Tritium dispersion simulation in the atmosphere by the integral transform technique using micrometeorological parameters generated by large eddy simulation
In this work, we report a numerical and statistical comparison between Advection-Diffusion Multilayer Method (ADMM) and Generalised Integral Laplace Transform Technique (GILTT) approaches to simulate a radioactive pollutant dispersion in the Atmospheric Boundary Layer (ABL) using micrometeorological parameters generated by Large Eddy Simulation (LES). To better describe the wind profile of the ...
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Utilisation and integration of interdisciplinary computer models into a tool for analysing ozone production from transportation sources
High ozone levels detected over large inland areas in Israel triggered an analysis of air mass back-trajectory, which pointed to the coastal Tel-Aviv metropolitan transportation system as the origin of the ozone's precursors. In order to link the transportation emissions to ozone formation, interdisciplinary modelling systems were utilised and integrated. The transportation-to-ozone formation ...
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What is Dissolved Oxygen and How to Measure?
Learn all about dissolved oxygen and how to measure it accurately. This comprehensive guide covers everything you need to know about dissolved oxygen, its importance, measurement techniques, and FAQ Introduction Dissolved oxygen (DO) is a crucial parameter in water quality assessment and plays a vital role in the survival of aquatic life. It refers to the amount of oxygen gas present in water, ...
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Real-time tracking of accidental atmospheric releases: LOSTRAC software
The LOSTRAC software is devoted to real-time tracking of accidental atmospheric releases. It allows one to calculate, within a few minutes from the moment when the accident is reported and localised, displacement and diffusion of atmospheric pollution. It also provides short-term evolution forecasting. It should become one of the tools for assisting the authorities in charge of safety operations ...
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How Does the Membrane Aerated Biofilm Reactor Work?
Aerobic digestion and nitrification-denitrification work together thanks to an innovative membrane system One of the most talked-about new wastewater treatment technologies is the membrane aerated biofilm reactor (MABR), which is revolutionizing WWT. The discussion, however, has mainly focused on issues like MABR technology’s low operating expenses, high energy efficiency, low ...
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SITHERMO: Development of a Novel Lidar System for the Profiling of Atmospheric Aerosols and Temperature (project code: Τ1ΕDΚ-02525) - Case study
Program: Operational Program «Competitiveness, Entrepreneurship and Innovation», under the call RESEARCH – CREATE – INNOVATE Starting date: 25/05/2018 Duration: 36 Μonths Summary: The object of the project is to develop the know-how and subsystems required for the construction of the first global lidar trading system for the simultaneous measurement of aerosols and ...
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Evaluation of the influence of micrometeorological data on concentration estimates
A dispersion model for continuous releases of pollutants in the atmospheric boundary layer is applied to study the influence on modelled concentrations of different estimates of the key micrometeorological variables that represent the dispersion processes. The modelling approach is based on the advection-diffusion equation and includes profiles of wind and eddy diffusivity for the entire ...
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On the new parameterisation of the eddy diffusivity for radioactive pollutant dispersion
In the present work, starting from the evolution equation for the turbulent energy density spectrum, we develop a new model for the growth of the turbulence in convective boundary layer. We apply dimensional analysis to parameterise the unknown inertial transport and convective source term in the dynamic equation for the three-dimensional spectrum. The non-linear integro-differential equation is ...
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Aeolian dust in sediment: a re-examination of methods for identification and dispersal assessed by diffuse reflectance spectrophotometry
Analyses of aeolian sediments present two main challenges: (1) when aerosol particles are collected on atmospheric filters, only a small amount of aeolian material is normally present, and (2) in these and other samples, the aeolian sediment is typically mixed with other types of particles and the aeolian material often makes up only a small percentage of the total sample. Diffuse Reflectance ...
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Pollutants in Urban Wastewater and Sewage Sludge
Untitled Document Executive Summary Water policy in the European Union is aiming to promote sustainable water use and a major objective of the new Water Framework Directive (2000/60/EC) is the long-term progressive reduction of contaminant discharges to the aquatic environment in urban wastewater (UWW). Sewage sludge is also a product of wastewater treatment and the Urban Waste ...
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