With the technical assistance of Z. Blaxek, M. R6bl, and E. Sladkova and the statistical evaluation of Z. Roth

Objective: The Czech Hydrometeorological Institute (CHMI) estimated the transboundary transport of air pollution between the Czech Republic and Poland by assessing relationships between weather conditions and air pollution in the area as part of the "Air Quality Information System in the Polish-Czech border of the Silesian and Moravian-Silesian region" project (http://www.air-silesia.eu). Estimation of cross-border transport of pollutants is important for Czech-Polish negotiations and targeted measures for improving air quality. Methods: Direct measurement of PM 10 and sulphur dioxide (SO 2) concentrations and the direction and wind speed from measuring stations in the vicinity of the Czech-Polish state border in 2006-2012. Results: Taking into account all the inaccuracies, simplifications and uncertainties, by which all of the measurements are affected, it is possible to state that the PM 10 transboundary transport was greater from the direction of Poland to the Czech Republic, rather than the other way around. Nevertheless, the highest share of the overall PM 10 concentration load was recorded on days with a vaguely estimated airflow direction. This usually included days with changing wind direction or days with a distinct wind change throughout the given day. A changeable wind is most common during low wind speeds. It can be assumed that during such days with an ambiguous daily airflow, the polluted air saturated with sources on both sides of the border moves from one country to the other. Therefore, we could roughly ascribe an equal level of these concentrations to both the Czech and Polish side. Conclusions: PM 10 transboundary transport was higher from Poland to the Czech Republic than from the opposite direction, despite the predominant air flow from the Czech Republic to Poland.

No abstract

La désaimantation d'un échantillon polycristallin par un champ alternatif évanescent conduit à un état de référence anisotrope si la substance possède plusieurs axes de facile aimantation. Après avoir rappelé les causes physiques de cette “anisotropie de la désaimantation”, les auteurs développent un modèle qui rend compte quantitativement du phénomène dans le cas d'un polycristal de structure cubique ayant, comme le fer, une forte anisotropie et ses axes de facile aimantation suivant les axes quaternaires du cristal. Nous avons d'abord calculé l'influence de cette anisotropie sur l'aimantation dans le domaine de Rayleigh. Puis nous avons montré comment, grǎce à des mesures de susceptibilité, il était possible de déterminer les paramètres caractérisant cette anisotropie, de manière à pouvoir confronter le modèle avec l'expérience. Nous avons enfin étendu le calcul de Néel relatif aux lois Rayleigh au cas d'un polycristal cubique et nous avons recherché les quantités introduites dans cette théorie que permet de déterminer la confrontation du modèle avec l'expérience.

The defibrillation threshold for various wave forms of condenser discharge, using capacitors from 4 to 200 µF, has been measured. Condenser discharge alone was used, or condenser discharge 0.25 henry (20 ohms) with an iron core series inductance, or condenser discharge, 0.29 henry (27 ohms) inductance, but without the iron core. Statistical analysis of the results showed that the last of these three circuits gave the lowest threshold voltage values. Optimal parameters of inductance-altered discharges are obtained with values of 24, 32, and 50 µF. Detailed analysis of the separate physical parameters of the discharge show that optimal pulse duration is 8.5 to 16.6 msec. Further increase of duration does not decrease the voltage or current for threshold shocks, but merely increases the energy delivered. Pulse duration appears to be one of the more important parameters for successful defibrillation, and for this reason, a series inductance is also important.