Carbon dioxide capture and storage (CCS) is considered as one of the options for reducing CO2 emissions. CCS can be applied to large point sources of CO2, such as power plants and in large industrial processes. The CO2 capture is to produce a concentrated stream of highpressure CO2. The capture systems typically employ absorption of CO2 from flue gases with CO2 concentration up to 15 %. The oxygen-fuel systems use oxygen instead of air for fuel combustion to produce mainly water vapour and CO2 (more than 80 %); the water vapour is easily removed by cooling. In precombustion capture, the fuel is converted to CO2 (15-60 %) and H2 at high pressure; then CO2 is separated by adsorption or absorption. The emerging capture technologies require development of largescale membrane separation processes, novel absorption solvents and sorbents, membrane-absorbent systems, hightemperature oxygen transport membranes for oxygen production, oxyfuelling via chemical looping, combined reaction/ separation systems and new high-temperature materials.
Quantification of carbon (C) fluxes in mycorrhizal plants is one of the important yet little explored tasks of mycorrhizal physiology and ecology. (13)CO2 pulse-chase labelling experiments are increasingly being used to track the fate of C in these plant-microbial symbioses. Nevertheless, continuous monitoring of both the below- and aboveground CO2 emissions remains a challenge, although it is necessary to establish the full C budget of mycorrhizal plants. Here, a novel CO2 collection system is presented which allows assessment of gaseous CO2 emissions (including isotopic composition of their C) from both belowground and shoot compartments. This system then is used to quantify the allocation of recently fixed C in mycorrhizal versus nonmycorrhizal Medicago truncatula plants with comparable biomass and mineral nutrition. Using this system, we confirmed substantially greater belowground C drain in mycorrhizal versus nonmycorrhizal plants, with the belowground CO2 emissions showing large variation because of fluctuating environmental conditions in the glasshouse. Based on the assembled (13)C budget, the C allocation to the mycorrhizal fungus was between 2.3% (increased (13)C allocation to mycorrhizal substrate) and 2.9% (reduction of (13)C allocation to mycorrhizal shoots) of the plant gross photosynthetic production. Although the C allocation to shoot respiration (measured during one night only) did not differ between the mycorrhizal and nonmycorrhizal plants under our experimental conditions, it presented a substantial part (∼10%) of the plant C budget, comparable to the amount of CO2 released belowground. These results advocate quantification of both above- and belowground CO2 emissions in future studies.
- MeSH
- Photosynthesis physiology MeSH
- Glomeromycota physiology MeSH
- Plant Roots metabolism MeSH
- Medicago truncatula metabolism microbiology MeSH
- Mycorrhizae metabolism MeSH
- Carbon Dioxide chemistry metabolism MeSH
- Carbon metabolism MeSH
- Plant Shoots metabolism MeSH
- Publication type
- Journal Article MeSH
In the current era of globalization, a clean environment remains a crucial factor for the health of the population. Thus, improving air quality is a major focus of environmental policies, as it affects all aspects of nature, including humans. For these reasons, it is appropriate to take into account the health risks posed by greenhouse gas (GHG) emissions released into the atmosphere. With regard to global GHG emissions, there are concerns about the loss of protection of the ozone layer and it is very likely that climate change can be expected, which multiplies the environmental threat and has potentially serious global consequences. In this regard, it is important to pay increased attention to emissions that enter the atmosphere, which include countless toxic substances. The aim of this study was to examine the associations between selected GHG emissions and the health of the European Union (EU) population represented by disability-adjusted life years (DALYs). This aim was achieved using several analytical procedures (descriptive analysis, correlation analysis, cluster analysis, and panel regression analysis), which included five environmental variables (carbon dioxide (CO2), methane (CH4) in CO2 equivalent, nitrous oxide (N2O) in CO2 equivalent, hydrofluorocarbons (HFC) in CO2 equivalent, sulfur hexafluoride (SF6) in CO2 equivalent) and one health variable (DALYs). An emphasis was placed on the use of quantitative methods. The results showed that CO2 emissions have a dominant position among selected GHG emissions. The revealed positive link between CO2 and DALYs indicated that a decrease in CO2 may be associated with a decrease in DALYs, but it is also true that this cannot be done without reducing emissions of other combustion products. In terms of CO2, the least positive scores were observed in Luxembourg and Estonia. Germany had the lowest score of DALYs, representing the most positive health outcome in the EU. In terms of total GHG emissions, Ireland and Luxembourg were considered to be less positive countries compared to the other analyzed countries. Countries should focus on reducing GHG emissions in general, but from a health point of view, reducing CO2 emissions seems to be the most beneficial.
- MeSH
- European Union MeSH
- Humans MeSH
- Methane analysis MeSH
- Nitrous Oxide analysis MeSH
- Carbon Dioxide MeSH
- Greenhouse Gases * analysis MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
In the Mediterranean ecosystem, wildfires are very frequent and the predicted future with a probable increase of fires could drastically modify the vegetation scenarios. Vegetation fires are an important source of gases and primary emissions of fine carbonaceous particles in the atmosphere. In this paper, we present gaseous and particulate emissions data from the combustion of different plant tissues (needles/leaves, branches and needle/leaf litter), obtained from one conifer (Pinus halepensis) and one deciduous broadleaf tree (Quercus pubescens). Both species are commonly found throughout the Mediterranean area, often subject to wildfires. Experiments were carried out in a combustion chamber continuously sampling emissions throughout the different phases of a fire (pre-ignition, flaming and smoldering). We identified and quantified 83 volatile organic compounds including important carcinogens that can affect human health. CO and CO2 were the main gaseous species emitted, benzene and toluene were the dominant aromatic hydrocarbons, methyl-vinyl-ketone and methyl-ethyl-ketone were the most abundant measured oxygenated volatile organic compounds. CO2 and methane emissions peaked during the flaming phase, while the peak of CO emissions occurred during the smoldering phase. Overall, needle/leaf combustion released a greater amount of volatile organic compounds into the atmosphere than the combustion of branches and litter. There were few differences between emissions from the combustion of the two tree species, except for some compounds. The combustion of P. halepensis released a great amount of monoterpenes as α-pinene, β-pinene, p-cymene, sabinene, 3-carene, terpinolene and camphene that are not emitted from the combustion of Q. pubescens. The combustion of branches showed the longest duration of flaming and peak of temperature. Data presented appear crucial for modeling with the intent of understanding the loss of C during different phases of fire and how different typologies of biomass can affect wildfires and their speciation emissions profile.
- MeSH
- Biomass MeSH
- Pinus chemistry MeSH
- Tracheophyta chemistry MeSH
- Quercus chemistry MeSH
- Air Pollutants analysis MeSH
- Monoterpenes analysis MeSH
- Particulate Matter analysis MeSH
- Gases analysis MeSH
- Wildfires * MeSH
- Dust analysis MeSH
- Trees chemistry MeSH
- Volatile Organic Compounds analysis MeSH
- Terpenes analysis MeSH
- Publication type
- Journal Article MeSH
Zmenou olovnatých benzínov na nízkoolovnaté a bezolovnaté došlo k zmenám v zložení emisií motorových vozidiel v zmysle nárastu koncentrácií oxidov dusíka a prchavých organických látok (VOC), z nich najmä benzénu, 1,3-butadiénu a formaldehydu, u vozidiel bez katalyzátorov i oxidu uhličitého (skleníkový plyn). Práca porovnáva riziká z obsahu olova a z obsahu VOC a uvádza niektoré literárne Údaje o rizikách environmentálneho benzénu. Výpočet celoživotného rizika našej populácie z orientačných meraní koncentrácií benzénu pri cestných ťahoch podľa metodiky WHO a US-EPA poukazuje na možný vplyv tejto škodliviny na incidenciu leukémie u nás. Záverom sú prezentované dôsledky prechodu na bezolovnatý benzín na životné prostredie a návrh opatrení na obmedzovanie zdravotných i environmentálnych rizík z emisií motorových vozidiel.
The change from leaded petrol to low-lead or lead-free petrol led to changes in the composition of motor car emissions, i.e. an increase of concentrations of nitrogen oxides and volatile organic compounds (VOC); among latter in particular benzene, 1, 3-butadiene and formaldehyde and in cars without a catalyzer also of carbon dioxide (glasshouse gas). The author compares the risk ensuing from lead with those of VOC and presents some data from the literature on risks of environmental benzene. The calculation of the life-long risk of our population from preliminary assessment of the benzene concentrations along higways, assessed by the method of WHO and US-EPA indicated the possible influence of this noxious substance on the leukaemia in this country. Finally the author gives account of the consequences of the change to unleaded petrol on the environment and presents suggestions for provisions to reduce and environmental risk caused by emmisions of motor vehicle.
Reducing fuel consumption and thus CO2 emissions is one of the most urgent tasks of current research in the field of internal combustion engines. Water Injection has proven its benefits to increase power or optimize fuel consumption of passenger cars. This technology enables knock mitigation to either increase the engine power output or raise the compression ratio and efficiency while enabling λ = 1 operation in the complete engine map to meet future emission targets. Current systems have limited container capacity. It is necessary to refill the water tank regularly. This also means that we cannot get the benefits of an engine with a higher compression ratio. For this reason, the self-contained system was investigated. This article is a methodology for finding the right design of a self-contained water injection system, but also a vehicle test that proves the function.
- MeSH
- Automobiles MeSH
- Gasoline * analysis MeSH
- Water MeSH
- Vehicle Emissions * analysis MeSH
- Research MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Phytomanagement of trace element-contaminated soils can reduce soil toxicity and restore soil ecological functions, including the soil gas exchange with the atmosphere. We studied the emission rate of the greenhouse gases (GHGs) CO2, CH4, and N2O; the potential CH4 oxidation; denitrification enzyme activity (DEA), and glucose mineralization of a Cu-contaminated soil amended with dolomitic limestone and compost, alone or in combination, after a 2-year phytomanagement with a mixed stand of Populus nigra, Salix viminalis, S. caprea, and Amorpha fruticosa. Soil microbial biomass and microbial community composition after analysis of the phospholipid fatty acids (PLFA) profile were determined. Phytomanagement significantly reduced Cu availability and soil toxicity, increased soil microbial biomass and glucose mineralization capacity, changed the composition of soil microbial communities, and increased the CO2 and N2O emission rates and DEA. Despite such increases, microbial communities were evolving toward less GHG emission per unit of microbial biomass than in untreated soils. Overall, the aided phytostabilization option would allow methanotrophic populations to establish in the remediated soils due to decreased soil toxicity and increased nutrient availability.
The chemical composition of emissions from old-type (an overfire boiler, a boiler with down-draft combustion) and modern-type (an automatic and a gasification boiler) boilers was compared. The boilers were operated with different fuels (brown and hard coal, wet and dry wood, wood pellets and brown coal briquettes) with reduced output (40-60%). The emissions were characterized by the contents of gaseous components (NOx, SO2, CO, CO2, OGC); and particulate organic compounds (alkanes, polycyclic aromatic hydrocarbons, saccharides), including organic markers (monosaccharide anhydrides, diterpenoids, methoxyphenols, hopanes), which are used for source apportionment of particulate matter in ambient air. In general, emissions of the products of incomplete combustion (CO, particles, polycyclic aromatic hydrocarbons) were higher from the combustion of solid fuels in old-type boilers than from that in modern-type boilers. The modern-type (especially automatic) boilers were the most environmentally friendly. The highest concentrations of particulate matter (81.6-89.4 g kg-1) and particulate organic compounds (sum of PAHs: 225-275 mg kg-1) including organic markers were found in emissions from old-type (overfire) boilers, especially with the combustion of brown and hard coal. Characteristic ratios of selected organic compounds/markers applied for source identification were calculated. Computed characteristic ratios for monosaccharide anhydrides (biomass combustion) agreed with values in the literature. Homohopane indexes, frequently used for identification of coal combustion, and other characteristic ratios for PAHs, were different from the literature data. In our opinion, characteristic ratios for PAHs are not suitable for use in source apportionment.
This study reports the first Co2 (CO)8 -catalyzed [2+2+2] polycyclotrimerization by the transformation of internal ethynyl groups of aromatic diyne monomers. The reaction yields polycyclotrimers of polyphenylene-type with either hyperbranched or partly crosslinked architecture. The homopolycyclotrimerization of the monomers with two ethynyl groups per one molecule, namely 1,4-bis(phenylethynyl)benzene, 4,4'-bis(phenylethynyl)biphenyl, and 4-(phenylethynyl)phenylacetylene, gives partly crosslinked, insoluble polyphenylenes. The soluble, hyperbranched polyphenylenes are generated via copolycyclotrimerization of 1,4-bis(phenylethynyl)benzene with 1,2-diphenylacetylene (average number of ethynyl groups per monomer molecule < 2). This one-step polycyclotrimerization path to hyperbranched or partly crosslinked polyphenylenes is an alternative to the synthesis of these polymers by Diels-Alder transformation of substituted cyclopentadienones. All polyphenylenes prepared exhibit photoluminescence with emission maxima ranging from 381 to 495 nm. Polyphenylenes with a less compact packing of segments are microporous (specific surface area up to 159 m2 g-1 ), which is particularly important in the case of soluble polyphenylenes because they can be potentially used to prepare microporous layers.
As national efforts to reduce CO2 emissions intensify, policy-makers need increasingly specific, subnational information about the sources of CO2 and the potential reductions and economic implications of different possible policies. This is particularly true in China, a large and economically diverse country that has rapidly industrialized and urbanized and that has pledged under the Paris Agreement that its emissions will peak by 2030. We present new, city-level estimates of CO2 emissions for 182 Chinese cities, decomposed into 17 different fossil fuels, 46 socioeconomic sectors, and 7 industrial processes. We find that more affluent cities have systematically lower emissions per unit of gross domestic product (GDP), supported by imports from less affluent, industrial cities located nearby. In turn, clusters of industrial cities are supported by nearby centers of coal or oil extraction. Whereas policies directly targeting manufacturing and electric power infrastructure would drastically undermine the GDP of industrial cities, consumption-based policies might allow emission reductions to be subsidized by those with greater ability to pay. In particular, sector-based analysis of each city suggests that technological improvements could be a practical and effective means of reducing emissions while maintaining growth and the current economic structure and energy system. We explore city-level emission reductions under three scenarios of technological progress to show that substantial reductions (up to 31%) are possible by updating a disproportionately small fraction of existing infrastructure.
- MeSH
- Climate Change * MeSH
- Environmental Monitoring * MeSH
- Carbon Dioxide analysis MeSH
- Climate * MeSH
- Industry MeSH
- Cities MeSH
- Geography MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- China MeSH
- Cities MeSH
