Effect of synthesis conditions on the properties of magnetic nanoflowers

Magnetic nanoflowers (MNF) can be applied in complementary cancer therapy treatment, however, some of the preparation conditions and stability experiments have not been examined in great detail. In this study, magnetite nanoparticles (NPs) with flower-like architecture were synthesized, characterized and tested by magnetic hyperthermia. The preparation and characterization of flower-shaped magnetic objects were optimized in two types of reaction vessels. The two different synthesis methods resulted in magnetic nanoparticles (MNP) of slightly different morphology, resulting in different behavior for hyperthermia. The stability of the NPs was achieved by the application polymer functionalization both by in situ and postcoating methods

Hidroszférák, folyadékszférák a Naprendszer bolygótestjein

A cikk összehasonlító planetológiai áttekintést kíván adni a földi hidroszféra vonatkozásában a Naprendszer bolygótestjeiről (szilárd felszínű bolygók és kb. 400 km-nél nagyobb holdak, törpebolygók). A cél, hogy mai ismereteink alapján bemutassuk a Föld különleges helyzetét a Nap bolygórendszerében

Two distinct sources of magnetospheric heating in the atmosphere: the aura and the ring current

In this paper, we demonstrate that, besides the well-known corpuscular heating of auroral origin, there is another heat source in the equatorial region of the neutral upper atmosphere acting during and after geomagnetic storms as a consequence of the precipitation of ring current ions. The effect of the two sources has been separated on the basis of their induced diurnal variations using measurements from the CACTUS micro-accelerometer. In Almár and Illés-Almár [Adv. Space Res., this issue, 2004, doi:10.1016/j.asr.2003.04.060], the observational facts and our suggestion for the improvement of the CIRA'86 model are summarized to draw the attention of the constructors of the new CIRA model on two effects that are not yet built into the earlier CIRA models. In the present paper, we try to outline the possible physics behind the observational facts necessitating the improvement of the model

Weather reacting to geomagnetic storms

In the first 15 years of the Space Age satellite position measurements derived from visual and photographic observations helped to determine the decay rate of satellites, by means of which the first models of the upper-atmosphere have been calculated. Our group concentrated on the study of the geomagnetic effect and collected several ten thousand observations from Europe and from Asia before and after geomagnetic storms. It was already conspicuous during data gathering that there are considerably less satellite observations in the time periods following almost every geomagnetic storm than in the preceding ones – indicating that the cloudiness might increase considerably after geomagnetic storms. The paper presents the statistical treatment of this phenomenon

New results concerning the geomagnetic effect in the upper atmosphere

89 equivalent duration values based on more than 30000 satellite observations were used to derive relations between different geomagnetic parameters and the correlated changes in upper atmospheric density during magnetospheric storms. The results demonstrate how the storm-time relative density increase depends on the intensity of the magnetospheric storm, on the altitude of the perigee and on its geocentric distance from the center of the diurnal bulge

Neutral density depletions attributed to plasma bubbles

Neutral density measurements in the equatorial thermosphere by the accelerometer of the San Marco V satellite in 1988 indicate from time to time sudden density depletions of 10-20 s. As the occurrence of such events maximizes between 1700 and 0300 hours local solar time, we interpret them as manifestations of the crossings of plasma bubbles by the satellite