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This work investigates thermal radiation in oxy-fuel flames, based on experiments and modelling. Experiments were conducted in a 100 kW test facility in air and oxy-fuel combustion atmospheres, using two different types of fuels, lignite and propane. In-flame measurements of gas composition, temperature and total radiation intensity, were performed and used as input to radiation modelling to examine the influence of oxy-fuel conditions on gas and particle radiation characteristics. In the modelling, the spectral properties of CO2 and H2O are treated by means of a statistical narrow band model and particle radiation is modelled for both scattering and non-scattering particles.Experiments on the propane flame show that the flame radiation conditions are drastically influenced by the recycling conditions. With OF 27 conditions (27% oxygen in the feed gas) and dry recycling, the temperature is slightly lower compared to air-fired conditions, but the emitted intensity is significantly increased. Modelling shows that this is mainly caused by a significantly increased soot radiation. Propane flame images show that the presence of soot in oxy-fuel conditions varies strongly with recycling conditions. The contribution due to an increased emission by CO2 is of minor importance. In the lignite experiments similar flame temperatures were kept during air and oxy-fuel combustion (OF 25 conditions with dry recycling). The measurements show that the intensity levels in both flames are similar which is due to a strong particle radiation in both environments. The modelling reveals that the dominance by particle radiation contra gas radiation is closely related to whether the particles are scattering or non-scattering. 相似文献
106.
This article elaborates on and discusses gendered dimensions of climate change response in Swedish municipalities. There are indications that attitudes and behaviour to the environment and climate change are gendered. This evidence together with our own work further indicates that gender awareness is most probably an important influence on how municipalities respond to climate change. The aim of this study was to investigate if and how gendered aspects of climate change response are integrated in the Swedish response to climate change. The potential causal relationships between a high level of awareness of the gendered aspects of climate change and the levels of climate change response were investigated. We asked whether there is a positive relationship between gender awareness and the quality of the communities' climate change policies and practice. Indications of such a relationship prompt a change in research priorities – paying more attention to gender – and in subsequent policy developments. 相似文献
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Martin J. Steinbauer Fredrik Östrand Tom E. Bellas Anna Nilson Fredrik Andersson Erik Hedenström Michael J. Lacey P. Florian Schiestl 《Chemoecology》2004,14(3-4):217-223
Summary. The autumn gum moth, Mnesampela privata
(Guenée) (Lepidoptera: Geometridae), is native to Australia
and can be a pest of plantation eucalypts. Field-collected
and laboratory-reared female autumn gum moths were
dissected to remove glands likely to contain components of
the sex pheromone. Using gas chromatography (GC) and
combined gas chromatography–mass spectrometry (GC-MS),
three compounds were identified from female extracts,
namely (3Z,6
Z,9
Z)-3,6,9-nonadecatriene, 1-hexadecanol
and 1-octadecanol (confirmed by comparison with synthetic
samples). Nonadecatriene elicited an antennal response in
male autumn gum moth during gas chromatographic
analyses combined with electroantennographic detection
(GC-EAD). In electroantennogram (EAG) recording male
M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis,
starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid
(linolenic acid) and propanoic acid or via an alternative
four-step method also starting from linolenic acid. In field
trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive
to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9-
nonadecatriene is a sex pheromone component of autumn
gum moth. This component has been identified in extracts
from other geometrids in the same subfamily, Ennominae.
However, to our knowledge this is the first example where
(3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females
and also proved attractive to male moths when presented on its
own. Our results are discussed in relation to other geometrid
pheromones. 相似文献
109.
Berta Andersson 《Environmental monitoring and assessment》1990,14(1):23-43
Information about visible symptoms of forest damage was collected during 1984–1987 from 13 reference areas established by the Swedish Environmental Monitoring Programme. The annual occurence of needle loss on Norway spruce and Scots pine was estimated visually and expressed as a percentage of defoliation on the upper parts of the tree-crowns. As the reference areas are situated all over Sweden from Lat. 55° to 69° the climate factors, such as temperature, winds, drought, humidity and snow cover, vary within a wide range. There are also altitudinal differences-sites are situated from 50 to 720 m above sea level. Two of the northernmost sites, which are also the high altitude ones, had the highest defoliation values. In the south, the most severely defoliated trees were growing on sites near the western and the eastern coasts. The estimated defoliation level was mainly lower in 1986 and 1987, compared with the level in 1984. A wide range of environmental factors influence tree health. Trees are subjected to several kinds of stress-factors causing several kinds of damage. Besides the natural stresses, there is also, a long-term effect of air pollutants. Diversity in resistance and susceptibility to air pollutants, as well as the exposition to winds and humidity, are affecting needle loss.The exposures to chemicals occurring under forest conditions are different at different parts of Sweden. The observed defoliation of conifers does not seem to have a linear relationship with the pollution gradient but are also attributable to natural stress factors. 相似文献
110.
Barbro Andersson 《Chemosphere》1982,11(4):357-361
Gas chromatography with a flame ionization detector and gas chromatography-mass spectrometry were employed in the analysis of dichlorophene used in the nursery cultivation of pine and spruce. The analysis was performed in paper and peat after the conversion of dichlorophene to its dimethyl other. With multiple ion detection a sensitivity of 1 mg/g paper or peat was achieved. 相似文献