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Untersuchungen zum Vorkommen polycyclischer Moschus-Duftstoffe in verschiedenen Umweltkompartimenten
Hans -Dietrich Eschke Heinz -Jürgen Dibowski Josef Traud 《Environmental Sciences Europe》1995,7(3):131-138
In addition to the three compounds discussed in our first communication (UWSF 6/4, 183–189, 1994) this paper mentions another four substances from the group of the polycyclic musk flavors analysed in a number of detergents and cosmetics, in surface waters, in waste waters from municipal sewage treatment plants and in fish. These four substances are: 6-acetyl-1,1,2,3,3,5-hexamethylindane (AHMI, known for instance under the trade name Phantolide®), 6,7-dihydro-1,1,2,3,3-pentamethyl-4 (5H)-indanone (DPMI, known for instance under the trade name Cashmeran®), 7-acetyl-1,1,4,4-tetramethyl-6-ethyltetraline (ATTN, known for instance under the trade name Versalide®) and 5-acetyl-1,1,2,6-tetramethyl-3-isopropylindane (ATII, known for instance under the trade name Traseolide®). The results of these analyses show that except for ATTN, the manufacture of which was discontinued some ten years ago, these substances are considered to have an ubiquitous distribution in surface waters. This pollution evidently comes from the use of these flavors in various detergents and cosmetics, from where they enter surface waters via the waste waters from municipal sewage treatment plants. Choosing the Ruhr river as an example, the authors demonstrate that the pollution level is constant and that — due to their lipophilic nature — the compounds accumulate in fish leading to concentrations which markedly exceed those known, e.g., for nitromusk flavors in environmental samples. Two of the main contaminants are HHCB and AHTN, which have the highest concentrations both in the detergents analyzed and in environmental samples. 相似文献
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Ultrastructural and chemical characterization of egg surface of honeybee worker and queen-laid eggs 总被引:3,自引:0,他引:3
Tamar?Katzav-GozanskyEmail author Victoria?Soroker Josef?Kamer Claudia?M.?Schulz Wittko?Francke Abraham?Hefetz 《Chemoecology》2003,13(3):129-134
Summary. Worker policing in honeybees predicts the
evolution of a mechanism to discriminate between queenand
worker-born eggs. Although it has been postulated that
this discrimination is based on an egg recognition
pheromone, neither the chemistry nor the glandular source
were elucidated. To verify whether egg discrimination might
be based on structural differences, we compared the ultrastructure
surface of queen-laid diploid and haploid eggs to
that of worker-laid eggs using SEM. Only small differences
between the different types of eggs were found. Thus, at
least based on the fine structure of the egg surface, queen
eggs are indistinguishable from worker-laid eggs.To explore the chemosensory hypothesis for egg discrimination,
we conducted a detailed comparative chemical
analysis of the different egg types. The coating of all egg
types was dominated by linear alkanes, but queen eggs,
diploid and haploid, differed from those of workers on two
accounts: 1. The diversity of compounds found on queenlaid
eggs was much greater than found on worker-laid eggs,
mainly due to the number of hydrocarbons. 2. Acetates of
some fatty alcohols, alkenes and especially monomethylalkanes
were characteristic to queen eggs. The origin of the
two latter substances and the acetates is still unknown.
Whether these compounds constitute the signal that enables
police workers to discriminate between queen- and workerborn
eggs remains to be investigated. 相似文献
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Josef Riederer 《Die Naturwissenschaften》1983,70(10):480-484
Scientific analysis of glass, excavations, and written evidence in Greek and Roman literature provide reliable information on the manufacture of glass in antiquity. In the second millenium BC, when other vitreous materials had already been known for 3000 years, hollow glass was produced in Egypt. From the early sandcore technique the manifold methods of glassmaking by casting in molds, blowing in molds, and free blowing then rapidly evolved. These techniques achieved their highest perfection in the Roman period when elaborate techniques for surface decoration were developed, but not rediscovered until recently. 相似文献
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Švec Roman Martinát Stanislav Pícha Kamil Klusáček Petr Knotek Jaroslav Schaefer Justin Calvin Březinová Monika Navrátil Josef 《Environment, Development and Sustainability》2021,23(10):15074-15099
Environment, Development and Sustainability - Our aim is to determine the factors influencing a visitor’s decision to stay in a green accommodation facility. Visitors from six tourist sites... 相似文献