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Abstract: Residential wood combustion is a widespread practice in Europe with a serious impact on air quality, especially in mountainous areas. While there is a significant number of studies conducted in deep urbanized valleys and basins, little is known about the air pollution processes in rural shallow hollows, where around 30 % of the people in mountainous areas across Europe live. We aim to determine the influence of ground temperature inversions on wood combustion aerosol pollution in hilly, rural areas. The study uses Retje karst hollow (Loški Potok, Slovenia) as a representative site for mountainous and hilly rural areas in central and south-eastern Europe with residential wood combustion. Sampling with a mobile monitoring platform along the hollow was performed in December 2017 and January 2018. The backpack mobile monitoring platform was used for the determination of equivalent black carbon (eBC) and particulate matter (PM) mass concentrations along the hollow. To ensure high quality of mobile measurement data, intercomparisons of mobile instruments with reference instruments were performed at two air quality stations during every run. Our study showed that aerosol pollution events in the relief depression were associated with high local emission intensities originating almost entirely from residential wood burning and shallow temperature inversions (58 m on average). The eBC and PM mass concentrations showed stronger associations with the potential temperature gradient (R2=0.8) than with any other meteorological parameters taken into account (ambient temperature, relative humidity, wind speed, wind direction, and precipitation). The strong association between the potential temperature gradient and pollutant concentrations suggests that even a small number of emission sources (total 243 households in the studied hollow) in similar hilly and mountainous rural areas with frequent temperature inversions can significantly increase the levels of eBC and PM and deteriorate local air quality. During temperature inversions the measured mean eBC and PM2.5 mass concentrations in the whole hollow were as high as 4.5±2.6 and 48.0 ± 27.7 µg m−3, respectively, which is comparable to larger European urban centres.
Keywords: air pollution, black carbon, sources, temperature inversion, mountainous area
Published in RUNG: 03.05.2022; Views: 1354; Downloads: 0
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Abstract: The master thesis aims to find the optimal model for a new energy company that considers regional potential, supports sustainable development, and fits the circular economy concept in a region. The idea of sustainable development is crucial today when we have more city areas and less countryside around the globe. Increased global population, industrial trends and modern living style are some of the reasons why the burden on our environment is more significant than ever in the history of humanity. The idea is to launch the new company in the Croatian region Osijek-Baranja, which is less developed and not attractive to tourists. A newly established company will produce electric energy from renewable energy sources. The multi-criterion decision support methods were used to determine the optimal energy source between wind, biogas and sun. Results show that the biogas has the most significant sustainable potential in chosen boundary conditions. The cash flows and other economic indicators are shown for a farm of 500 milking cows in the chosen region as a source of biogas. The risk assessments method estimated the boundaries of the company success and adaptability to possible changes. One of the critical aspects of the project is the company's organizational structure, where a vertical hierarchy with a flexible and fluid, circular organization model with network culture was proposed. Clear communication about the project will help establish trust with the local community. Based on the biogas plant, the proposed company reduces biodegradable waste in the green energy production process. It is shown quantitatively that besides being economically sustainable, it also suits the region's potential, supports energy self-supply, and involves local people - it aims to the long-term sustainable growth of the region, rather than short-term capital growth.
Keywords: Circular economy, sustainable development, regional potential, renewable energy sources, company structure, communication
Published in RUNG: 18.02.2022; Views: 2453; Downloads: 66
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Abstract: X-ray absorption spectroscopy (XAS) is a powerful tool for characterisation of local structure and chemical state of selected elements in different new functional materials and biological or environmental samples. The XAS spectroscopy is based on extremely bright synchrotron radiation X-rays sources, which allow precise characterisation of bulk, nanostructured or highly diluted samples. The rapid development of extremely bright synchrotron sources of X-ray and ultraviolet light in recent years has opened new possibilities for research of matter at the atomic or molecular level, indispensable in the development of new functional nanostructured materials with desired properties. The lecture will present the possibilities offered by X-ray absorption spectroscopy with synchrotron light for ex-situ and in-situ or operando characterization of various functional porous and other nanomaterials before, after and during their operation. With the operando micro-XANES and EXAFS methods it is possible to track changes in the valence states and local structures of selected elements in different energy storage materials or in various (photo)catalysts, during chemical reactions under controlled reaction conditions, thus gaining insight into the dynamic functional properties and reaction mechanisms of these materials. New synchrotron light sources also opened the possibility of combining X-ray absorption or emission spectroscopy and microscopy with a resolution of up to a few tens of nanometres, crucial for analysis of environmental and biological samples on sub-cellular level, to understand the mechanisms of uptake, transport, accumulation, and complexation of metal cations on subcellular level in various plant tissues or accumulation in environment, to develop effective remediation approaches.
Keywords: X-ray absorption spectroscopy, EXAFS, XANES, synchrotron radiation sources, operando
Published in RUNG: 15.12.2021; Views: 1782; Downloads: 0
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Abstract: The ecological footprint of modern life exceeds the biocapacity of our environment in Slovenia as well. With a simplified monetization of natural resources and waste, the economic and environmental advantages of renewables compared to fossil sources in the case of energy supply of buildings were illustrated. Experience with current energy market volatility and the extension of the EU-ETS are strong signals to accelerate the energy transition towards sustainable energy also in the building sector.
Keywords: energy supply, renewable energy sources, EU-ETS, buildings
Published in RUNG: 29.10.2021; Views: 1861; Downloads: 0
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Abstract: Motivated by the detection of a significant dipole structure in the arrival directions of ultra-high-energy cosmic rays above 8 EeV reported by the Pierre Auger Observatory (Auger), we search for a large-scale anisotropy using data collected with the surface detector array of the Telescope Array Experiment (TA). With 11 yr of TA data, a dipole structure in a projection of the R.A. is fitted with an amplitude of 3.3% ± 1.9% and a phase of 131° ± 33°. The corresponding 99% confidence-level upper limit on the amplitude is 7.3%. At the current level of statistics, the fitted result is compatible with both an isotropic distribution and the dipole structure reported by Auger.
Keywords: cosmic rays, ultra-high-energy cosmic radiation, cosmic ray sources, cosmic ray showers, cosmic ray detectors, cosmic ray astronomy, extragalactic astronomy
Published in RUNG: 05.02.2021; Views: 2371; Downloads: 0
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