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| Registros recuperados: 50 | |
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| Persoone, G.. |
| The displacement technique for measuring the volume of plankton catches is well established, and a number of papers have been published describing suitable apparatus for this purpose including those by Frolander (1957), and Yentsch & Hebard (1957). Gnanamuthu (1952) reviews several papers dealing with equipment for measuring the volume of small aquatic animals and discusses his own volumeter. The apparatus here described employs a water column and is, therefore, more convenient to handle than previous designs which used a mercury column. It is inexpensive and simple to construct, and will measure to 0.01 or even 0.005 ccm. We have found it most useful in quickly measuring the volume of polychaetes or oligochaetes, small bivalves, small crustaceans, etc. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Instruments; Marine invertebrates. |
| Ano: 1971 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3430 |
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| Persoone, G.; Morales, J.; Verlet, H.; De Pauw, N.. |
| Since turbulence is an important factor for the growth of microscopic algae, the effect of mixing intensity and mixing time, has been assessed by means of air-lift pumps as an alternative technology for the agitation of algal cultures. Batch culture experiments in enriched sea water were carried out indoors with <i>Chlorella</i> in 100 liter tanks and outdoors with natural phytoplankton populations in 70 m³ tanks. The respective culturing depths in these tanks were 25 and 180 cm. The role of the mixing was also evaluated against that of the pH regulation of the cultures. Mixing with air-lift pumps increased the algal growth rate significantly in comparison to non-agitated cultures. The yields were also much higher (up to 30%) in mixed than in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Algae culture. |
| Ano: 1980 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3692 |
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| Persoone, G.; Sorgeloos, P.. |
| 1. A simple cylindrical hatching and separator box is described for <i>Artemia salina</i>nauplii (and other phototactic invertebrates), in which the "corner seeking effect" responsible for poor separation is avoided, and from which nauplii can be recovered very conveniently. 2. Separation is achieved by partly unscrewing an internal and closed cylinder from its fixed counter-part glued to the bottom of the box, till two slits are freed through which the nauplii migrate from the darkened internal hatching cylinder into the illuminated exterior compartment. Rescrewing the former cylinder separates the larvae from debris and unhatched eggs. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hatching; Instruments; Nauplii; Phototaxis; Artemia. |
| Ano: 1972 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3460 |
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| Persoone, G.. |
| Growth on submerged substrates (fouling or "Aufwuchs") has already been the object of numerous studies especially with regard to its economic implications. The scarcity of investigations on the influence of pollution on development and evolution of the fouling-biocoenosis is surprising. As far as we know the smaller fauna and flora in this particular situation have never been studied quantitatively. Therefore, in 1963, 1964 and 1965, a number of experiments were carried out in the harbour of Ostend (Belgium) on submerged substrates of different nature, in order to study the following less known aspects of fouling: a) the successive stages in the development of fouling, from bacteria to macro-organisms. b) the influence of several factors on its... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fouling Harbours Marine pollution ANE; Belgium; Oostende Harbour. |
| Ano: 1971 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3431 |
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| Poels, C.L.M.; Fischer, R; Fukawa, K.; Howgate, P.; Maddock, B.G.; Persoone, G.; Stephenson, R.R.; Bontinck, W.J.. |
| A test guideline has been established for determining the potential of a chemical to taint seafood. This guideline, based on the exposure of fish and the evaluation of the imparted taint by a triangular test, has been evaluated in a small ring test in which five laboratories tested four chemicals with three fish species. The guideline also contains a procedure for estimating the loss of taint from the test species during a depuration phase in clean water. None of the following factors appeared to have a large or systematic effect on the evaluation of the potential to cause taint: the performing laboratory; type of water used (sea- or freshwater); fish species; evaluation by flavour or by odour; method of preparation and presentation of samples for sensory... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1988 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3155 |
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| Persoone, G.. |
| Predictive hazard assessment of chemicals, pure, in mixtures, or as wastes, is based on the comparison of exposure to effect concentrations. Experimental determination of no-effect levels can be carried out at various levels of biological organisation: within the organism (suborganismal), on individual species (organismal), or with biological communities (supraorganismal). The difficulty of predictive effect analysis consists of relating endpoints determined at various levels of biological organisation to the impact on structure and/or function impairment of natural ecosystems. Examples are given of effect-extrapolations which have been validated at different levels, and which carry promising predictive values. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1988 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3154 |
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| Persoone, G.; Deplaecie, M.. |
| During ecological investigations on the optimum culturing conditions of ciliates, we studied the influence of a number of abiotic factors on the reproductive potential of the hypotrichous ciliate <i>Euplotes vannus</i> Muller, such as the nature and the quantity of food, the temperature and the salinity. The experiments were run in petri dishes of 5 cm diameter containing 5 ml of food suspension, and were always started with conjugants. The microphagous <i>Euplotes vannus</i> thrives on a variety of food media. Excellent results were observed on homogenized bakers yeast, i.e. 10.000-20.000 animals in 5 ml of food suspension. In good culturing conditions the stationary phase was reached in 7 days, which implicates a mean rate of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Reproduction Euplotes vannus ANE; Belgium; Oostende Harbour. |
| Ano: 1972 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3468 |
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| Registros recuperados: 50 | |
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