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101.
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Measurements show that PCN may occur in industrial waste and residues in the mg/kg range. Investigations were carried out with optimized parameters for GC and MS using two different GC/MS-systems. Chromatograms were obtained for a variety of chlorination degrees using capillary columns of different polarities. It is proposed to quantify PCN using relevant single compounds comparable to the analysis of polychlorinated biphenyls.  相似文献   
103.
The results of investigations of the aquatic ecotoxicity of sternutators and their metabolites (phenyl arsenic compounds) are presented. The standardized luminescence inhibition test (LumisTox, Dr. Lange) with the marine bacteriaVibrio fischeri was applied according to the German norm DIN 38412, part 34. All investigated organic AS(III) compounds exhibit EC50-values (50 % inhibition of the luminescence) of less than 1 mg/l, whereas all investigated organic As(V) compounds and inorganic arsenic show EC50-values exceeding 100 mg/l  相似文献   
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H. Schmidt 《Marine Biology》1972,15(3):265-278
Strombolicchio is a rocky islet situated about 1.6 km northeast of the isle of Stromboli. The islet consists of three steep walls having different light and surface conditions. The zonation on the northern wall differs essentially from the zonation found in caves because of the greater turbulence. On smooth rocks near the water surface, there is only one actinian species which resists turbulence, Actinia equina. The best turbulence resisting anthozoan species are the scleractinians (Astroides calycularis Balanophyllia verrucaria). They are followed by stolonial growing forms (Paralcyonium elegans, Cornularia cornucopiae). All other actinians settle in crevices and small holes. The turbulence prevents Parazoanthus axinellae and Corynactis viridis from settling on the smooth rock near the surface. Therefore, these species occur on Strombolicchio only at comparatively deep levels. As a result of being forced to settle in crevices, space competition occurs among the various actinian species. Cereus pedunculatus, Aiptasia mutabilis, and Telmatactis forskalii co-exist, while Anemonia sulcata lives isolated in few crevices only. Contrary to other localities, A. sulcata is not the most abundant actinian species on Strombolicchio. Most frequent are the viviparous forms of Cereus pedunculatus and Actinia equina mediterranea. This mode of reproduction is rather rare in these species in the Mediterranean Sea, but common in the Atlantic Ocean. It is supposed that the viviparous varieties of Strombolicchio are geographical isolates of Atlantic populations. The influence of light on the colour of some anthozoans has also been studied. Zooxanthellae were found to be much more abundant in Aiptasia mutabilis in darkness than in bright surface waters. Gerardia savaglia proved to be quite abundant in deeper caves and on overhanging walls; it is more sciaphilic than Paramuricea clavata. Paralcyonium elegans occurs near the surface as well as at different depth levels; it has been observed in differing growth forms, corresponding to different patterns of turbulence. Alcyonium brioniense is considered to be a growth form of Alcyonium acaule.  相似文献   
107.

Objective

Flood sediments were investigated due to the extreme flood situation around Dresden in August 2002

Method

The samples have been analyzed by screening inorganic and organic pollutants.

Results

It was observed that As, Pb, Cd, Zn, Cu, B and other heavy metals as well as DDT, PCB and Benzo [a] pyren were significantly enriched.

Conclusion

Depending on geogenic and anthropogenic impacts, the spatial distribution of these contaminants was different. Organic compounds were dislocated down stream from Czech Republic along the Elbe River. Because of the old ore mining, samples near the Mulde and Wei\eritz Rivers showed high metal pollution.

Perspective

More detailed and systematic investigations should be undertaken in the Elbe and Mulde river systems.  相似文献   
108.
This report documents the extent to which coral colonies show fluctuations in their associations with different endosymbiotic dinoflagellates. The genetic identity of Symbiodinium from six coral species [Acropora palmata (Lamarck), A. cervicornis (Lamarck), Siderastrea siderea (Ellis and Solander), Montastrea faveolata (Ellis and Solander), M. annularis (Ellis and Solander), and M. franksi (Gregory)] was examined seasonally over five years (1998 and 2000–2004) in the Bahamas and Florida Keys at shallow (1 to 4 m) fore-reef/patch reef sites and at deeper fore-reef (12–15 m) locations. Symbionts were identified genetically using denaturing gradient gel electrophoresis (DGGE) fingerprinting of the internal transcribed spacer region 2 (ITS2) of ribosomal RNA gene loci. Repetitive sampling from most labeled colonies from the Bahamas and the Florida Keys showed little to no change in their dominant symbiont. In contrast, certain colonies of M. annularis and M. franksi from the Florida Keys exhibited shifts in their associations attributed to recovery from the stresses of the 1997–1998 El Niño southern oscillation (ENSO) event. Over several years, a putatively stress-tolerant clade D type of Symbiodinium was progressively replaced in these colonies by symbionts typically found in M. annularis and M. franksi in Florida and at other Caribbean locations. Greater environmental fluctuations in Florida may explain the observed changes among some of the symbioses. Furthermore, symbiotic associations were more heterogeneous at shallow sites, relative to deep sites. The exposure to greater environmental variability near the surface may explain the higher symbiont diversity found within and between host colonies.  相似文献   
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In a laboratory colony of the asexual solitary endoparasitoid Venturia canescens Grav. (Hymenoptera: Ichneumonidae), two genetically and phenotypically distinct lines (RP and RM) appear to coexist sympatrically, with the reproductive success of the RM-line being greater under con-specific superparasitism but lower under self superparasitism. To investigate the basis of the RM-lines advantage under con-specific superparasitism, we examined the outcome of inter-larval physical combat under in-vitro conditions. The results showed that the outcome depended on both the relative and absolute ages of the contestants, and that the competitive abilities of the two lines were not symmetric. In contests involving a larva and an egg, the unhatched wasp lost. In contests involving two larvae, at least one of which was newly hatched, the RP-larva tended to lose. Finally, if both larvae were at least 8–10 h post-hatching when the contest occurred, then the larger larva tended to lose, with the probability increasing with the difference in length between the two larvae. Thus, the higher reproductive success of the RM-line under competing superparasitism with the RP-line is due to a physiological difference between the newly hatched larvae of the two lines, which results in an advantage to the RM-larva independent of the order or time interval between ovipositions.Communicated by P. Heeb  相似文献   
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