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Environmental Fluid Mechanics - In this laboratory study, propagation behaviour, particle deposition patterns, and suspension characteristics of non-cohesive particle-driven gravity currents formed... 相似文献
876.
G. Yuan D. Chen L. Yin Z. Wang L. Zhao J.Y. Wang 《Waste management (New York, N.Y.)》2014,34(6):1045-1050
In this research a gas–liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas–liquid fluidized bed reactor was running at 280–320 °C, where hot N2 was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N2 to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N2 gas was set around 0.47–0.85 Nm3 kg?1 for the molten PVC. Larger N2 flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N2 flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas–liquid fluidized bed reactor for dechlorination. 相似文献
877.
Florence Censier Christophe Y. Fischer Sandrine Chavalle Stephanie Heuskin Marie-Laure Fauconnier Bernard Bodson Michel De Proft Georges C. Lognay Pascal Laurent 《Chemoecology》2014,24(6):243-251
The saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae), has undergone a resurgence recently as a pest of cereals in Belgium and other European countries. An effective monitoring tool of saddle gall midge flights is needed to understand the enigmatic population dynamics of this pest, and to design an integrated management strategy. Therefore, volatile compounds emitted by females (alkan-2-ols and alk-2-yl butanoates) were identified, and the chirality of the emitted esters was determined to be the R absolute configuration. In field-trapping experiments, racemic non-2-yl butanoate attracted substantial numbers of H. marginata males. Thus, this compound will be useful in baited traps for monitoring seasonal flight patterns, and improving integrated management of the saddle gall midge in agricultural systems. 相似文献
878.
NYAMSUREN BATSAIKHAN BAYARBAATAR BUUVEIBAATAR BAZAAR CHIMED OIDOV ENKHTUYA DAVAA GALBRAKH OYUNSAIKHAN GANBAATAR BADAMJAV LKHAGVASUREN DEJID NANDINTSETSEG JOEL BERGER JUSTIN M. CALABRESE ANN E. EDWARDS WILLIAM F. FAGAN TODD K. FULLER MICHAEL HEINER TAKEHIKO Y. ITO PETRA KACZENSKY PETER LEIMGRUBER ANNA LUSHCHEKINA E.J. MILNER‐GULLAND THOMAS MUELLER MARTYN G. MURRAY KIRK A. OLSON RICHARD READING GEORGE B. SCHALLER ANNAGRET STUBBE MICHAEL STUBBE CHRIS WALZER HENRIK VON WEHRDEN TONY WHITTEN 《Conservation biology》2014,28(6):1736-1739
879.
K. Itoh Y. Mihara Y. Toshima K. Suyama 《Journal of environmental science and health. Part. B》2013,48(2):181-190
Monochlorophenols were degraded to benzoate via phenol by the initial dechlorination and the subsequent conversion of phenol to benzoate in anaerobic sediment samples of estuarine Lake Shinji under methanogenic conditions. To characterize bacteria that dechlorinate 4-chlorophenol and transform phenol to benzoate, we analyzed the microbial community structure of the enrichment culture with each 4-chlorophenol and phenol by the limiting dilution method with polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of 16S rRNA gene. After serial dilution of the culture, the 4-chlorophenol-dechlorinating culture consisted of two dominant bacteria, one of which was most homologous with Dehalobacter sp. In the enriched culture with phenol, minor band homologous with Cryptanaerobacter phenolicass corresponded to the transformation activity. 相似文献
880.
Life history parameters of ”old endemics” and ”new invaders” among the Australian passerines were compared, controlling for
phylogeny by using current, phylogenetic research methods. Old endemics were found to have significantly smaller clutches
and demonstrated significantly more cooperative breeding than the new invaders, whose fledging periods are significantly longer
than those of the old endemics. We argue that breeding under conditions of a small annual food increment during the breeding
season, as is probably the situtation in Australia, is possible only when clutch size is small, or while breeding cooperatively,
or by extending the fledging period. Our data show that the old endemics use the first two options, while the new invaders
employ the third.
Received: 10 February 1999 / Received in revised form: 10 November 1999 / Accepted: 20 November 1999 相似文献