Ti O 2 nanotube layers were grown on titanium by a self-organized anodic oxidation. The layers consist of arrays of individual tubes with a length of ∼2μm, a diameter of ∼100nm, and a wall thickness of ∼10nm. These layers can be annealed to an anatase structure which strongly increases the photocurrent efficiency. Moreover, the nanotube layers can—under certain conditions—exhibit a drastically enhanced photocurrent compared to compact anatase layers. These strong changes in the photoresponse are attributed to the characteristics of the space charge layer within the tube wall.

The present work deals with self-organized TiO 2 nanotube layers formed on a Ti metal substrate by anodization. For virtually any electrical or photoelectric application, these originally amorphous nanotube layers need to be converted to anatase. Most frequently, this is done by annealing at temperatures of approximately 450°C. In the present work we use TEM and XRD to compare the annealing at a significantly lower temperature of 350°C with that at the established 450°C. HRTEM results show that both annealing

The mechanical properties of oxide scales at high-temperature were studied in order to improve the surface quality of commercial Sicontaining high strength steels. Specific oxides of Fe 2 O 3 , Fe 3 O 4 , FeO and Fe 2 SiO 4 were synthesized by powder metallurgy. The Vickers hardness, thermal expansion coefficient and thermal conductivity were measured at high-temperatures. A series of measurements confirmed that the physical properties of the synthesized oxides were different each other. From the Vickers hardness measurements, it was verified that the hardness of each synthesized oxide was identical with the naturally-formed iron oxide, as observed in the cross-section of oxide scales on steels. The influence of the Fe 2 SiO 4 formed on Si-containing steels on the scale adhesion at high temperature and the surface property is discussed on the basis of the physical properties of the oxides.

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The purpose of this study is to elucidate the interaction between the cell and the surface of poly(L-lactide) (PLLA) samples, which were modified using a low-temperature plasma treatment apparatus at atmospheric pressure. The plasma treatments were carried out in the atmospheres of air, carbon dioxide (CO2), and perfluoro propane (C3F8) gas. The PLLA samples before and after the plasma treatment were analyzed by XPS and their contact angles with water. Furthermore, the cell adhesion capability and cell mass culturing tests on the PLLA samples were carried out using MC3T3-E1 cells. The results showed that the contact angle of the samples, which was plasma treated in air or in CO2 gas, decreased compared with that of the untreated samples. On the other hand, the contact angle of the samples, which was plasma treated in the C3F8 gas, increased compared with the untreated plasma samples. The cell response on the PLLA samples plasma treated in air or in the CO2 gas were significantly superior to that of the PLLA samples, which was plasma treated in the C3F8 gas.

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