Martin Kopani, Milan Mikula, Daniel Kosnac, Jan Gregus and Emil Pincik
The morphology and chemical bods of p-type and n-type porous Si was compared. The surface of n-type sample is smooth, homogenous without any features. The surface of p-type sample reveals micrometer-sized islands. FTIR investigation reveals various distribution of SiOxHy complexes in both p-and n-type samples. From the conditions leading to porous silicon layer formation (the presence of holes) we suggest both SiOxHy and SiFxHy complexes in the layer.
Ľubor Dlháň, Roman Krylov, Martin Kopáni and Roman Boča
Bovine spleen has been used as a sample for deep magnetochemical investigation. Temperature dependence of the magnetic susceptibility and field dependence of the magnetization reveal a paramagnetic behaviour that violates the Curie law. The zero-field cooled magnetization and field cooled magnetization experiments show the bifurcation point at ca TC = 20 K and the blocking temperature TB = 10 K confirming a dominating portion of ferritin along with the organic tissue. There is a remnant magnetization at temperature below 20 K and the search for the magnetic hysteresis was positive.
Miroslava Makohusová, Viera Mrázová, Martin Kopáni and Roman Boča
Deposits of iron oxides in the human brain (globus pallidus) are visible under electron microscopy as object of regular and or/irregular shape but giving sharp diffraction patterns in the transmission mode. The SQUID magnetometry reveals that the magnetization curves decline form an ideal Langevin function due to the dominating diamagnetism of organic tissue. The fitting procedure yields the quantitative characteristics of the overall magnetization curves that were further processed by statistical multivariate methods