ABSTRACT
Titanium dioxide (TiO2) is widely used in various major industries owing to its different crystal forms and functions. Therefore, fabricating suitable crystalline TiO2 through reasonable processes is necessary. In this study, Fe-doped TiO2 precursors were prepared via hydrolysis. Further, in situ high-temperature X-ray diffraction and transmission electron microscopy were used to transform the synthesized precursor in its crystal form. The Rietveld full-spectrum fitting method could accurately yield two different crystal forms at instant temperatures. Additionally, the rate relation between the crystal form transformation and reaction conditions was obtained. Results showed that the addition of Fe increased the temperature of phase transition of TiO2 anatase to rutile and accelerated the anatase â rutile transformation process. Further, crystal phase transition kinetic analysis showed that the phase transition kinetic model of Fe-doped TiO2 matched the Johnson-Mehl-Avrami-Kohnogorov (JMAK) model and that its phase transition was affected by crystal defects. Finally, Fe3+ in Fe-doped TiO2 was reduced to Fe2+ to generate oxygen vacancies, thus promoting the rate of transformation from titanium ore to rutile.
ABSTRACT
OBJECTIVE: To systematically evaluate the effects of finasteride on hematuria associated with benign prostatic hyperplasia (BPH). METHODS: We electronically searched MEDLINE (December 1966-April 2009), EMBASE (December 1974-April 2009), The Cochrane Library (Issue 1, 2009), CNKI (December 1994-April 2009), VIP (December 1989-April 2009) and CBM (December 1978-April 2009) , and handsearched several relevant journals as well. Randomized controlled trials were assessed with the methods recommended by the Cochrane Collaboration. The data were screened and systematically analyzed by at least two reviewers independently using the RevMan 5.0 software. RESULTS: Compared with the placebo control group, the finasteride group showed a significantly decreased incidence of hematuria during the 12 months follow-up period (OR 0.11, 95% CI: 0.06-0.21, P < 0.05). CONCLUSION: Finasteride has desirable therapeutic and preventive effects on BPH-associated hematuria. More well-designed multicentered randomized controlled trials of large sample size are invited to provide further evidence for this conclusion.
