Unsymmetrical molecular interactions cause curvature in the double layers (depicted below) that arise from the crystallization from CHCl3 of the title enantiomer prepared by allylboration. Platelets without curvature are formed from the corresponding racemate. The curvature of these naturally occurring tubes thus depends on the chirality of the building blocks. Furthermore, the only piece of evidence for the chirality of the natural compounds comes from the curvature of its bilayer crystals.

As part of an international project dealing with genetic diversity in wild forage species of the Sahelian Zone, a preliminary investigation of soil algal crusts in highly degraded environments was made. Soil sealing and the formation of crusts belong to the complex mechanisms of desertification processes. The kinds of soil algae present in the crusts and their temporal dynamics through the seasons are of relevance for the understanding of these processes. Surface crust samples from two wet and two dry seasons were examined for their algal flora by culturing and microscopy, in order to assess the role of algae in such processes. At least two different types of crusts were distinguished: dark crusts with a high algal contribution, dominated by filamentous blue-green algae (cyanobacteria), and light crusts with a far lesser algal contribution. The development of cyanobacterial crusts over two years suggests a seasonality, with a codominance of coccal green algae during the dry seasons. On light soils, a gradient was also apparent in the algal flora from sealed to sandy patches. In long-term development of fast changing arid ecosystems such as the Sahel, soil algae might prove a useful bio-indicator in screening for desertification and revegetation.

Unsymmetrische molekulare Wechselwirkungen sind die Ursache dafür, daß sich die aus dem über eine Allylborierung hergestellten Titel‐Enantiomer beim Ausfällen aus CHCl3 entstehenden Doppelschichten krümmen, während sich aus Lösungen des entsprechenden Racemats Plättchen ohne Kurvatur bilden. Die Kurvatur dieser natürlich vorkommenden Röhrchen läßt sich demnach auf die Chiralität der Alkoholbausteine zurückführen.

The quantity, process and kinetics of di-(2-ethylhexyl)phthalate (DEHP) migration in the 30/70 and 40/60 poly(vinylchloride) (PVC)/DEHP blends were investigated using gas chromatograph. A thin and flexible PVC sheet was soaked in surrounding medium (SM) of water/ethanol mixture and acetonitrile with constant stirring to release DEHP. By observed concentration of DEHP in the SM, it is found that acetonitrile is more intense in DEHP migration than water/ethanol mixture. In addition the amount of extracted DEHP is proportional to the leaching temperature and added ratio of DEHP. The behavior of DEHP migration from flexible PVC sheets was described by the Ficks's law with 2.72-10.1 × 10 −10 cm 2 /s of the diffusion coefficients.

Scale‐bearing taxa of the chrysophytes are important paleoindicators because of their often restricted ecological requirements and their highly preserved extracellular siliceous structures. The diagnostic features can usually only be resolved using electron microscopy and, since these features are often shared between closely related taxa, identification in field studies remain uncertain in most cases. As the respective influences of genetics and environmental factors upon morphological variation cannot be evaluated in field studies, examinations were conducted by growing a clonal culture of Mallomonas tonsurata in different media with varying silicon, nitrogen and phosphorus supply, followed by micromorphological analyses of scales and bristles. Increased silica content resulted in significant elongation of scales with a corresponding tendency to build slender scales. In experiments with varied ratios of nitrogen and phosphorus in the media the most pronounced changes were observed under phosphorus enrichment leading to significantly larger scales and more needle‐like bristle tips. These bristles resemble those of M. areolata. This shows that bristles are more variable than scales and thus must be regarded as of little value for taxonomical description. However, the above‐mentioned changes are not sufficiently pronounced to result in a sharp distinction between two different species. This confirms that siliceous structures of chrysophytes are, in principle, a most valuable tool for taxonomic differentiation although in field studies morphological variability of taxonomically relevant characters should still be considered.