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Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Porous structures TiO2-Na0.8Ti4O8-Na2Ti6O13 were obtained by mixing, compacting and sintering TiO2 with sodium bicarbonate as porogenic agent (15 and 30 wt.% of NaHCO3). The samples were compacted and treated at 1100 °C for 4 h and 8 h. The effects of sintering time and the weight percent of NaHCO3 on surface mechanical properties, porosity and cytotoxicity were analyzed. The X-ray diffraction patterns were refined by the Rietveld method. Microstructures were observed by scanning electron microscopy and the effect of material composition on the cellular response in vitro was evaluated using a LDH-cytotoxicity assay. The porosity varied between 3.2% and 11.9%, the surface microhardness between 251.4 HV0.2 and 851.6 HV0.2. The cytotoxicity results on the CHO cell line (Chinese Hamster ovary) show that the porous structures are not cytotoxic and has potential for orthopedic tissue engineering applications. [ABSTRACT FROM AUTHOR]

In this work nanopowders of titanate of tetragonal barium ( BaTiO3) were produced. The synthesis was accomplished as from polymeric precursor method. Based in results yielded in literature, a study in terms of the variation went from the pH, principal accomplishedly than 7, of the precursive solution. This permitted establishing a reduction of the size of the particles of agglomerates in signs with different pH and ( among 10 and 40 nm ). The temperature of calcination for his part did not evidence difference any one with the variation of this parameter. [ABSTRACT FROM AUTHOR]

Copyright of Superficies y Vacío is the property of Sociedad Mexicana de Ciencia y Tecnologia de Superficies y Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dry powder method is a solid-state processing technique involving constant milling of the initial compounds for later calcination. This technique was used to prepare the compounds presented in this essay, using TiO2 and MgO in diferentes rates. To analyze the resulting compounds' morphology, Scanning electron microscope (SEM) was used. In the images taken from the TiO2 sample, groups of agglomerations and of grains were found. Nevertheless, it maintains a certain round pattern in both groups, in the shape of micrograins of 0.5-1 µm. SEM images from the MgO sample are typically laminar with barely a few microns of width. The comparative studies of their structural and spectral characteristics through X-ray Diffraction (XRD) confirmed the individual structure of each compound and also, new spectral lines are obtained which suggests that titanates were formed during the process. [ABSTRACT FROM AUTHOR]

Ferroelectric properties and the chemical bonding states of lead zirconate titanate PbZr0.52Ti0.48O3 (PZT) thin films grown on SrRuO3/SrTiO3 by RF sputtering were investigated with X-ray photoelectron spectroscopy (XPS). The binding energy of the elements in the surface was investigated, as a chemical composition of the PZT ferroelectric thin films. By mean of a Radiant Technologies System to ferroelectric measurements were obtained hysteretic loops of P-E at room temperature, with values of 35.3 µC/cm², 64.5 µC/cm² and 171 4 kV/cm for remanent polarization, saturation polarization and coercitive field, respectively. A correlation was obtained between bonding states and PZT thin films ferroelectric properties [ABSTRACT FROM AUTHOR]