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Semiconductor-based sensors have played an important role in efficient detection of combustible, flammable, and toxic gases, but they usually need to operate at elevated temperatures (200 °C or higher). Although reducing the operation temperature down to room temperature is of practical significance, it is still a huge challenge to fabricate room temperature sensors with a low cost. Here we show a novel "self-doping" strategy to overcome simultaneously both difficulties of "high resistance" and "low reaction rate", which have always been encountered for room-temperature operation of semiconductor-based sensors. In particular, a porous crystalline titania with heavily self-doped Ti3+ species has been prepared by using a porous amorphous Ti02 and urea as the starting materials. The resulting Ti3+ self-doped Ti02 material serves as an efficient room-temperature gas-sensing material for specific CO detection with fast response/recovery. The self-dopant (Ti3+) in the titania material has proved to decrease the resistance of Ti02 significantly on the one hand and to increase the chemisorbed oxygen species substantially, thus enhancing the surface reaction activity on the other. Such a self-doping concept is anticipated to give a fresh impetus to rational design of room-temperature sensing devices with low costs. [ABSTRACT FROM AUTHOR]

Little is known about the effects of titanium found in patients wearing prostheses or about the biochemical pathways of this metal when used as an anticancer drug (e.g., titanocene dichloride). In this work, transferrin has been confirmed as the only carrier protein binding Ti in human blood serum samples by making use of different HPLC protein separations followed by element-specific Ti detection by ICPMS. Besides, isotope dilution analysis has been applied to the quantitative speciation of Ti-Tf in standards and human blood serum samples. Species-unspecific and species-specific isotope dilution modes have been explored. In the first case, very low Ti-Tf results were obtained even using two different chromatographic mechanisms, anion exchange (20-24%) and size exclusion (33-36%). Surprisingly, no major Ti species except Ti-Tf were observed in the chromatograms, suggesting that Ti(IV) hydrolysis and precipitation as inactive titanium oxide species could take place inside the chromatographic columns. These results demonstrate that chemical degradation of metalloproteins during analytical separations could ruin the sought speciation quantitative results. The isotope dilution species-specific mode, much more accurate in such cases, has been instrumental in demonstrating the possibility of gross errors in final metalloprotein quantification. For this purpose, an isotopically enriched standard of 49Ti-Tf was synthesized and applied to the quantitative speciation of Ti-Tf again. Using this species-specific spike, Ti-Tf dissociation inside the chromatographic columns used could be corrected, and thus, quantitative Ti-Tf binding in serum (92-102%) was observed. In other words, the usefulness and potential of a species-specific isotope dilution analysis approach to investigate quantitatively metal-protein associations, which can be dissociated at certain experimental conditions, is demonstrated here for the first time. [ABSTRACT FROM AUTHOR]

Presents a method of isotope dilution mass spectroscopy for the determination of traces of heavy metals in high-purity titanium primary materials. Isotope ratios; Separation techniques for trace/matrix separation and element-specific isolation; Detection limits; Analysis of titanium samples.

A heterometallic metal--organic framework incorporating Zn2+ and Ti4+ is successfully synthesized. The unique coordination mode of each metal ion to 2-oxido-l,4-benzenedicarboxylate leads to Zn6Ti2 building blocks, which extend to form a double-walled primitive cubic net. This material possesses a permanent porosity and long-term stability [ABSTRACT FROM AUTHOR]

The article presents a study which identifies the synthesis, experimental, and computational characterization and the functional properties of Li2Ti(IO3)6 polar materials. It aims to understand the structural nature of the polarity and functional characteristics of polar materials. It examines the implication of the alignment of the lone pairs on the iodate group in the functional properties of Li2Ti(IO3)6.