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Ultrasonic treatment (sonication) of the Szczecin Lagoon sediment samples processed for examination of cladoceran remains
is described. As opposed to cladoceran remains from non-sonicated sediment, those extracted from the ultrasound-treated samples
were clean, easily stained, clearly visible in microscope slides and identifiable. Sonication is therefore recommended as
an aid in rendering cladoceran remains free of adhered particles that obscure the specimens and complicate their identification
in some sediments. 相似文献
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Gavand MR McClintock JB Amsler CD Peters RW Angus RA 《Marine pollution bulletin》2007,54(11):1777-1788
Uptake and release of ship-borne ballast water is a major factor contributing to introductions of aquatic phytoplankton and invasive macroinvertebrates. Some invasive unicellular algae can cause harmful algal blooms and produce toxins that build up in food chains. Moreover, to date, few studies have compared the efficacy of ballast water treatments against different life history phases of aquatic macroinvertebrates. In the present study, the unicellular green alga Dunaliella tertiolecta, and three discrete life history phases of the brine shrimp Artemia salina, were independently used as model organisms to study the efficacy of sonication as well as the advanced oxidants, hydrogen peroxide and ozone, as potential ballast water treatments. Algal cells and brine shrimp cysts, nauplii, and adults were subjected to individual and combined treatments of sonication and advanced oxidants. Combined rather than individual treatments consistently yielded the highest levels of mortality in algal cells (100% over a 2 min exposure) and in brine shrimp (100% and 95% for larvae and adults, respectively, over a 2 min exposure). In contrast, mortality levels in brine shrimp cysts (66% over 2 min; increased to 92% over a 20 min exposure) were moderately high but consistently lower than that detected for larval or adult shrimp. Our results indicate that a combination of sonication and advanced chemical oxidants may be a promising method to eradicate aquatic unicellular algae and macroinvertebrates in ballast water. 相似文献
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L. A. Pérez-Maqueda O. B. Caneo J. Poyato J. L. Pérez-Rodríguez 《Physics and Chemistry of Minerals》2001,28(1):61-66
The effect of ultrasounds on natural macroscopic vermiculite flakes has been studied. Conditions for the preparation of submicron
vermiculite particles of narrow particle-size distribution by sonochemistry are described. The resulting material is crystalline,
as assayed by X-ray diffraction. Effects of ultrasound treatment on the mean particle size, crystal structure, crystallite
dimensions in different directions, and specific surface area of the resulting particles are investigated. Under the conditions
used in this work, there is a practical limit at 40 h in the sonication time for the preparation of submicron particles; longer
treatment times promoted aggregation.
Received: 21 March 2000 / Accepted: 21 August 2000 相似文献
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