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[tBu 4 PcIn] 2 O are almost identical despite the difference in their saturation energy densities.In summary, spectroscopic data and excited relaxation data of the In-and Ga-Pcs employed in the present study do not show aggregation phenomena to reduce the effective nonlinear absorption. [8,13] The optical limiting in these compounds is very effective compared to other phthalocyanines [18] exhibiting a range of saturation densities and absorption cross-section ratios. Axial substitution of the p-TMP functional group at the central gallium and indium in 1 and 3 results in a reduction of the saturation energy density by a factor in excess of 3. This method of tailoring the saturation of the optical limiters will prove to be very useful in the construction of passive organic optical limiters where multiple layers of effective absorbers with decreasing saturation may be desirable. ExperimentalThe synthesis and structural characterization of compounds 1±5 have been previously reported [9,11,12]. All solvents used were purified, dried and distilled under dry nitrogen. UV-vis spectra were recorded in Shimadzu UV-365. Fluorescence spectra and lifetimes were measured by a single-photon counting method using an argon ion laser, a pumped Ti:sapphire laser (Spectra-Physics, Tsunami 3960, FWHM 150 fs) with a pulse selector (Spectra-Physics, 3980), a second harmonic generator (Spectra-Physics, GWU-23PS), and a streakscope (Hamamatsu Photonics, C4334-01). Each sample was excited in toluene with 410 nm laser light.The open aperture of a Z-scan experiment [16] was used to measure the optical limiting response in the samples. All experiments described in this study were performed using 6 ns 532 nm laser light pulses from a Q switched frequency doubled Nd:YAG laser with a pulse repetition rate of 10 Hz. The beam was spatially filtered to remove the higher order modes and tightly focused using a 9 cm focal length lens. All samples were measured in quartz cells with a 1 mm optical path length, and at concentrations of 0.5 g L ±1 (~10 ±4 M) in toluene. There is growing interest in attempts to combine biomaterials and inorganic nanoparticles and investigating their properties. One of the research motivations for this combination is to take advantage of the well-defined structures and special properties of biomolecules and their supermolecular structures to organize the nanoparticles into predefined, topologically intricate nanostructures or to synthesize miscellaneous materials for potential applications in electronic, optical, and chemical devices.[1] Several kinds of biomaterials have been

Specific cell adhesion and osteogenicity are both crucial factors for the long-term success of titanium implants. In this work, two mussel-derived bioactive peptides were designed to one-step dual-biofunctionalization of titanium implants via robust catechol/TiO coordinative interactions. The highly biomimetic peptides capped with integrin-targeted sequence or osteogenic growth sequence could efficiently improve the biocompatibilities of titanium implants and endow the implants with abilities to induce specific cell adhesion and enhanced osteogenicity. More importantly, rationally combined use of the two biomimetic peptides indicated an enhanced synergism on osteogenicity, osseointegration and finally the mechanical stability of Ti implants in vivo. Therefore, the highly biomimetic mussel-derived peptides and the dual-functional strategy in this study would provide a facile, safe, and effective means for improving clinical outcome of titanium-based medical implants.

The distribution of microbial communities in the Menggulin (MGL) and Ba19 blocks in the Huabei Oilfield, China, were studied based on 16S rRNA gene analysis. The dominant microbes showed obvious block-specific characteristics, and the two blocks had substantially different bacterial and archaeal communities. In the moderate-temperature MGL block, the bacteria were mainly Epsilonproteobacteria and Alphaproteobacteria , and the archaea were methanogens belonging to Methanolinea , Methanothermobacter , Methanosaeta , and Methanocella . However, in the high-temperature Ba19 block, the predominant bacteria were Gammaproteobacteria , and the predominant archaea were Methanothermobacter and Methanosaeta . In spite of shared taxa in the blocks, differences among wells in the same block were obvious, especially for bacterial communities in the MGL block. Compared to the bacterial communities, the archaeal communities were much more conserved within blocks and were not affected by the variation in the bacterial communities.