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In this work we provide a systematic explanation to the unusual non-monotonic behavior of the Hall resistance observed at two-dimensional electron systems. We use a semianalytical model based on the interaction theory of the integer quantized Hall effect to investigate the existence of the anomalous, i.e. overshoot, Hall resistance RH . The observation of the overshoot resistance at low magnetic field edge of the plateaus is elucidated by means of overlapping evanescent incompressible strips, formed due to strong magnetic fields and interactions. Utilizing a self-consistent numerical scheme we also show that, if the magnetic field is decreased the RH decreases to its expected value. The effects of the sample width, temperature, disorder strength and magnetic field on the overshoot peaks are investigated in detail. Based on our findings, we predict a controllable procedure to manipulate the maxima of the peaks, which can be tested experimentally. Our model does not depend on specific and intrinsic properties of the material, provided that a single particle gap exists.

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Fe 2 O 3 -TiO 2 coatings were successfully prepared on glass slide substrates using sol-gel method for photocatalytic applications. The phase structure, thermal, microstructure and surface properties of the coatings were extensively characterized by using X-ray diffractometry (XRD), differential thermal analysis/thermograviometry (DTA/TG), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Their adhesion and absorbance properties were investigated by a scratch tester and UV-vis spectroscopy. Four different solutions were prepared by changing Fe/Ti molar ratios. Glass substrates were coated by solutions of Ti-alkoxide, Fe-chloride, glaciel acetic acid and isopropanol. The obtained gel films were dried at 300 • C for 10 min and subsequently heat-treated at 500 • C for 5 min in air. The oxide thin films were annealed at 600 • C for 60 min in air. The influence of Fe 3+ concentration and number of layers on structure of the films was established. In addition, XRD results revealed that Fe 2 O 3 -TiO 2 films composed of TiO 2 , Fe 2 Ti 3 O 9 , Ti 3 O 5 and Fe 3 O 4 phases. According to DTA/TG result, it was determined that endothermic and exothermic reactions were formed at temperatures between 80 and 650 • C due to solvent removal, combustion of carbon based materials and oxidation of Fe and Ti. SEM observations exhibited that the coating structure becomes more homogeneous depending on an increase of Fe/Ti molar ratios and thus a regular surface morphology forms with increasing Fe/Ti ratio. It was also seen that as the Fe/Ti ratio increases the surface roughness of the films increases. Critical adhesion force of thin films with Fe/Ti ratio of 0, 0.07, 0.18 and 0.73 were found to be 9, 25, 28 and 21 mN, respectively. The methylene blue solutions photocatalyzed by TiO 2 based thin films shows characteristic absorption bands at 420 nm.

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