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951.
The objective of this paper is to evaluate the combustion process of municipal solid waste combustion in a grate furnace both experimentally and numerically by using data of a reference experiment with over-stoichiometric primary air supply. Measurements were carried out inside the combustion chamber of a pilot plant by monitoring temperatures and sampling gaseous combustion products along the bed surface. The data were assessed using elemental and energy balances. Experimental data of the axial temperature profiles of the flue gas, the fuel bed and the grate bars, as well as local gas flows and the flue gas composition measured above the fuel bed along the grate were used to describe the conversion process, including drying and carbon burnout. These data served as input to model the thermo- and fluid dynamic processes of the gas phase above the bed inside the combustion chamber. For this purpose the commercial code FLUENT was employed to carry out the simulations. Thus, the turbulent temperature, flow and species distributions in the combustion chamber of the pilot waste incinerator TAMARA were predicted. The results of the FLUENT modeling showed that under the prevailing conditions the flue gas burnout is almost completed before entering the first flue due to high temperatures, effective mixing and sufficient residence times of the flue gas inside the combustion chamber. This agrees well with the experimental results inside the first flue. On the basis of the above mentioned results, design and parametric studies can be carried out in a more efficient way by saving cost and time. 相似文献
952.
In a large area around the former open-pit lignite mines near Bitterfeld, Germany, groundwater taken from wells was analyzed for the major cations, anions, and trace elements. Quaternary and Tertiary sediments were collected from aquifers exposed on the sides of the pits and from boreholes outside the mines and analyzed for major and trace elements, as well as for carbonate, pyritic sulfur and total organic carbon. The pH and electrical conductivity of the sediments in suspension were measured. Significant differences were determined between the Tertiary sediments of the aquifers that were exposed to atmospheric oxygen during the lowering of the groundwater table and those outside the cone of depression. The greatest differences were found in the pyrite content, the pH values, and the electrical conductivity. In order to map the degree to which the mining of the lignite has affected the quality of the groundwater in the study area, the water samples were divided into six classes on the basis of their sulfate content. The neutralization potential was calculated to estimate the potential for acidification. Prediction of future groundwater quality is based on both (i) the present composition of the groundwater, surface water, and Quaternary and Tertiary aquifer sediments and (ii) the present and future groundwater flow directions. These studies have shown which parameters are important for future groundwater monitoring. 相似文献
953.
Hanedar Asude Çifçi Deniz İzlen Zafer Nur Görgün Erdem 《Journal of Material Cycles and Waste Management》2022,24(5):1760-1767
Journal of Material Cycles and Waste Management - In this study, the amount of medical waste generated in a high-populated city in Turkey between January 2018 and August 2021 was evaluated, and the... 相似文献
954.
Journal of Polymers and the Environment - In the present study, a graft copolymer was synthesized in accordance with the free radical method using N-tertiary butylacrylamide monomer on chitosan,... 相似文献
955.
Yüksel Bayram Ustaoğlu Fikret Tokatli Cem Islam Md Saiful 《Environmental science and pollution research international》2022,29(12):17223-17240
Environmental Science and Pollution Research - The objective of this paper was to stress the possible potential toxic element (PTE) accumulation in the surface sediments of the Çavu?lu... 相似文献
956.
Ünal Hüseyin Aktuğ Muhammet 《Environmental science and pollution research international》2022,29(30):45635-45645
Environmental Science and Pollution Research - This study investigates the effects of human capital, bio-capacity, energy use, and economic growth on the ecological footprint of G20 countries for... 相似文献
957.
958.
湿地植物对污水中氮、磷去除效果的试验研究 总被引:3,自引:1,他引:2
采用室内试验和现场试验考察了黄花鸢尾、水葱和梭鱼草3种挺水植物对类污水处理厂二级出水中氮、磷的吸收速率、吸收容量和吸收贡献。结果表明:短期内,各种湿地植物污水中氮、磷的吸收速率比较稳定,但在整个生长周期内,各种植物对氮、磷的吸收速率却有较大变化,4月份,水葱对氮、磷的吸收速率最大,8月份,梭鱼草对氮、磷的吸收速率最大。在整个生长期内,黄花鸢尾对氮、磷的吸收容量一直保持最大,在10月下旬分别达到21.5和4.16 g/m2,因此其对二级出水中氮、磷去除的吸收贡献也最大,分别为30%和73%。这表明湿地植物的选择不仅要考查其对污染物的吸收速率,更要关注其对污染物的吸收容量,并且湿地植物的吸收作用对类二级出水中氮、磷的去除具有更加重要的意义。 相似文献
959.
Bryaninops, Gobiodon, Paragobiodon and Pleurosicya are the most abundant genera of coral-associated gobies. These genera are adapted to live among coral, while other small
reef gobies (e.g., the genus Eviota) show no obligate association with this living substrate. Thirteen coral-associated species and two Eviota species were sampled from different regions of the Red Sea, along with four populations/species of Gobiodon from the Indian and western Pacific Oceans. A molecular phylogenetic analysis was performed using partial sequences of 12S
rRNA, 16S rRNA and cytochrome b mitochondrial genes, 1,199 base pairs in total. Several clades were consistently resolved in neighbor joining-, maximum parsimony-,
maximum likelihood and Bayesian analyses. While each of the four genera Gobiodon, Paragobiodon, Bryaninops and Pleurosicya proved to be monophyletic, their relative position in the phylogeny did not support an emergence of coral-associated gobiids
as a monophyletic assemblage. Instead, two separate monophyletic sub-groups were discovered, the first comprising Gobiodon and Paragobiodon, and the second Bryaninops and Pleurosicya. Our molecular phylogenetic examinations also revealed one unassigned species of Gobiodon from the Maldives as a distinct species and confirmed three putative and yet unassigned species from the Red Sea. Moreover,
the uniformly black colored species of Gobiodon are not monophyletic but have evolved independently within two distinct species groups. Genetic distances were large in particular
within Pleurosicya and Eviota. Estimated divergence times suggest that coral-associated gobies have diversified in parallel to their preferred host corals.
In particular, divergence times of Gobiodon species closely match those estimated for their typical host coral genus Acropora. 相似文献
960.
Plant chemistry and insect sequestration 总被引:2,自引:1,他引:1
Most plant families are distinguished by characteristic secondary metabolites, which can function as putative defence against
herbivores. However, many herbivorous insects of different orders can make use of these plant-synthesised compounds by ingesting
and storing them in their body tissue or integument. Such sequestration of putatively unpalatable or toxic metabolites can
enhance the insects’ own defence against enemies and may also be involved in reproductive behaviour. This review gives a comprehensive
overview of all groups of secondary plant metabolites for which sequestration by insect herbivores belonging to different
orders has been demonstrated. Sequestered compounds include various aromatic compounds, nitrogen-containing metabolites such
as alkaloids, cyanogenic glycosides, glucosinolates and other sulphur-containing metabolites, and isoprenoids such as cardiac
glycosides, cucurbitacins, iridoid glycosides and others. Sequestration of plant compounds has been investigated most in insects
feeding or gathering on Apocynaceae s.l. (Apocynoideae, Asclepiaoideae), Aristolochiaceae, Asteraceae, Boraginaceae, Fabaceae and Plantaginaceae, but it also occurs
for some gymnosperms and even lichens. In total, more than 250 insect species have been shown to sequester plant metabolites
from at least 40 plant families. Sequestration predominates in the Coleoptera and Lepidoptera, but also occurs frequently
in the orders Heteroptera, Hymenoptera, Orthoptera and Sternorrhyncha. Patterns of sequestration mechanisms for various compound
classes and common or individual features occurring in different insect orders are highlighted. More research is needed to
elucidate the specific transport mechanisms and the physiological processes of sequestration in various insect species. 相似文献