We report the processing, analysis and testing of magnetocaloric composite materials consisting of La-Fe-Co-Si particles of various size fractions and a polymer matrix. All of the composites have working temperatures close to room temperature. The composites were pressed into thin plates, a geometry favorable for testing the composites in an active magnetic regenerator (AMR). In order to investigate the influence of particle size and binder type (epoxy), eight different epoxy-bonded La-Fe-Co-Si plates were made and analyzed. We found that the higher filling factor that can be achieved by using a mixture of several particle size fractions has beneficial influence on the thermal conductivity. Tests in the AMR revealed that a maximum temperature span of approximately T = 10 K under magnetic field change of 0H = 1.15 T can be obtained at no cooling load conditions. The stability of the measured T values and the mechanical integrity of sample after cyclic application of a magnetic field have been monitored for 90.000 cycles and showed no significant changes. We therefore conclude that epoxy-bonded La-Fe-Co-Si magnetocaloric composites have good magnetocaloric properties at low material-processing costs and hence represent a competetive way to produce magnetocaloric materials to be used in AMR.

The possibility to enrich paramagnetic dysprosium(III) ions in a magnetic field gradient is proved by means of interferometry, which may open the route for a magnetic separation of rare earth ions from aqueous solutions. The separation dynamics are studied for three different concentrations of DyCl3 and compared with those found recently in a sulphate solution of the 3d ion Mn(II). In view of the similar-sized hydration spheres for Dy(III) and Mn(II), the slower separation dynamics in DyCl3 is attributed to both a higher densification coefficient and the strong impact of Brownian motion due to the absence of ion-pair clusters.

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The influence of different stress parameters in racing pigeon flocks, such as the presence of diseases and environmental conditions at the time of the races, were described. A total of 96 racing pigeons from 4 pigeon flocks were examined, and health monitoring was carried out. No helminth eggs and coccidia were found. Trichomonas sp. was confirmed in subclinical form. Paramyxoviruses and avian influenza viruses were not confirmed, but circovirus infections were confirmed in all flocks. Chlamydia psittaci was confirmed in one flock. Blood samples were collected, and HI antibody titers against paramyxoviruses before and 25 days after vaccination were determined. To improve the conditions during racing and the welfare of the pigeons, critical points were studied with regard to stress factors during the active training season. Serum corticosterone levels were measured in the blood serum of four different categories of pigeons from each flock. Corticosterone levels were almost twice as high in pigeons from the category that were active throughout the racing season, including medium- and long-distance racing, compared to the other three categories that were not racing actively. Within five hours of the finish of a race, the average serum corticosterone level was 59.4 nmol/L in the most physically active category. The average serum corticosterone level in this category remained at 37.5 nmol/L one month after the last race.