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The rotational viscosity coefficients γ1 are measured with the rotating field method as a function of temperature in the nematic phases of 4-methoxybenzylidene-4′-n-butylaniline, 4-n-pentyl-, and 4-n-octyl-4′-cyanobiphenyl, of the eutectic mixture of two 4-n-pentylphenyl 4-alkoxybenzoates and of the eutectic mixture of the two isomers of 4-methoxy-4′-n-butylazoxybenzene. Equations are proposed which describe the temperature dependence very well. The Leslie coefficients αi are calculated from the γ1 values and recently measured shear viscosity coefficients.

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The viscosity coefficients ql, q,, q3 and ql, of 4-n-pentyl-4'-cyanobiphenyl, Cn-octyl-4'-cyanobiphenyl. 4-methoxy-4-n-butyIazoxybenzene and an aromatic ester mixture were determined in the nematic phase region. Except for 4-n-octyl-4'-cyanobiphenyl, the viscosity coefficients of the liquid crystals show the following properties: 1) Three of the viscosity coefficients are related by an equation of the form Z A;']; = 0, in which the corresponding constants A; are very similar for the different liquid crystals. 2) The equation qi = aoqj + by is valid with the exception of the neighbourhood of the clearing point.3) The reduced viscosity coefficients 3qi/(ql + q2 + q3) of the different liquid crystals exhibit a very similar dependence on the reduced temperature and a nearly linear dependence on the degree of order. The viscosity coefficients q, and q1, of Cn-octyl-4'-cyanobiphenyl show a divergence at the transition to the smectic phase, whereas ql and q3 show the normal temperature dependence.

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In W 7-AS the H mode has been observed for the first time in a currentless stellarator plasma. H modes are achieved with 0.4 MW electron cyclotron resonance heating at 140 GHz at high density. The H phases display all characteristics known from tokamak H modes including edge localized modes (ELMs). The achievement of the H mode in a shear-free stellarator without toroidal current has consequences on //-mode transition and ELM theories.

A weather pattern based weather generator is used to determine projections of future climate changes in Germany. A SRES B2 run of the coupled atmosphere and ocean model ECHAM4-OPYC3 of the Max-Planck-Institute for Meteorology (Hamburg, Germany) and observations from several hundred climate stations of the German Weather Service are used as input data for the presented statistical model. The method described in this paper utilizes an objective circulation pattern classification and a specific weather generator to indicate the mean regional changes between present day climate and the future projection. A circulation pattern dependent regression is used to model future climate extremes resulting from changed intensities of atmospherical processes within the individual circulation patterns. The presented results are a composite of five regional climate studies. Generally the following statements can be inferred from our results: The predicted climate change will not progress uniformly. Instead, periods characterized by rather slight changes will be followed by others exhibiting very distinct climatologic alterations. The strongest change is identified in winter. Until the decade 2041-50 an increase of approximately 3 K and a raise of the rainfall amounts are predicted compared to the present day climate (1981-2000). This is caused by an increase of zonal circulation patterns. In summer the change is weaker but still significant. The temperature will increase approx. 2 K while rainfall will decrease especially in the south and east of Germany. The changes within the transitional seasons will be moderate compared to those within summer and winter. Zusammenfassung Ein wetterlagenbasierter Wettergenerator wird zur Projektion zukünftiger Klimaänderungen in Deutschland genutzt. Ein SRES B2 Lauf des gekoppelten Atmosphären-Ozean-Modell ECHAM4-OPYC3 vom Max-Planck-Institut für Meteorologie (Hamburg) und Daten von einigen hundert Klimabeobachtungsstationen des Deutschen Wetterdienstes werden als Eingangsdaten für das vorgestellte statistische Modell genutzt. Die in diesen Artikel beschriebene Methode nutzt eine objektive Wetterlagenklassifikation und einen Wettergenerator um die regionalenÄnderungen zwischen dem aktuellen Klima und den Prognosen abzuschätzen. Eine wetterlagenbasierte Regression wird genutzt um klimatische Extreme, die durch geänderte Intensitäten der Atmosphärischen Prozesse innerhalb der einzelnen Wetterlagen auftreten können, zu modellieren. Die vorgestellten Ergebnisse sind eine Zusammenstellung von fünf regionalen Klimastudien. Verallgemeinert können folgende Ergebnisse abgeleitet werden: Es gibt keine einheitliche Klimaänderung, sondern es werden sich Perioden mit kleinen und großenÄnderungen abwechseln. Die stärksteÄnderung findet im Winter statt. Für die Dekade 2041-50 ist ein Anstieg der Temperatur um etwa 3 K und eine Zunahme der Niederschlagsmengen im Vergleich zur Periode 1981-2000 vorhergesagt. Grund dafür ist ein deutlicher Anstieg zonaler Wetterlagen. DieÄnderungen im Sommer sind dagegen geringe...