One-dimensional (1D) conductive nanowire is one of the most important components for the development of nanosized electronic devices, sensors, and energy storage units. Great progresses have been made to prepare the 1D-conducting polymeric nanofibers by the low concentration process or the synthesis with hard or soft templates. However, it still remains as a great challenge to prepare polymeric nanofibers with narrow dispersity, high aspect ratio, and good processibility. With the rod-like tobacco mosaic virus as the template, 1D-conducting polyaniline and polypyrrole nanowires can be readily prepared via a hierarchical assembly process. This synthesis discloses a unique way to produce composite fibrillar materials with controlled morphology and great processibility, which can promote many potential applications including electronics, optics, sensing, and biomedical engineering.

Microbial communities in ultra-high-pressure (UHP) rocks and drilling fluids from the Chinese Continental Scientific Drilling Project were characterized. The rocks had a porosity of 1 to 3.5% and a permeability of ϳ0.5 mDarcy. Abundant fluid and gas inclusions were present in the minerals. The rocks contained significant amounts of Fe 2 O 3 , FeO, P 2 O 5 , and nitrate (3 to 16 ppm). Acridine orange direct counting and phospholipid fatty acid analysis indicated that the total counts in the rocks and the fluids were 5.2 ؋ 10 3 to 2.4 ؋ 10 4 cells/g and 3.5 ؋ 10 8 to 4.2 ؋ 10 9 cells/g, respectively. Enrichment assays resulted in successful growth of thermophilic and alkaliphilic bacteria from the fluids, and some of these bacteria reduced Fe(III) to magnetite. 16S rRNA gene analyses indicated that the rocks were dominated by sequences similar to sequences of Proteobacteria and that most organisms were related to nitrate reducers from a saline, alkaline, cold habitat; however, some phylotypes were either members of a novel lineage or closely related to uncultured clones. The bacterial communities in the fluids were more diverse and included Proteobacteria, Bacteroidetes, gram-positive bacteria, Planctomycetes, and Candidatus taxa. The archaeal diversity was lower, and most sequences were not related to any known cultivated species. Some archaeal sequences were 90 to 95% similar to sequences recovered from ocean sediments or other subsurface environments. Some archaeal sequences from the drilling fluids were >93% similar to sequences of Sulfolobus solfataricus, and the thermophilic nature was consistent with the in situ temperature. We inferred that the microbes in the UHP rocks reside in fluid and gas inclusions, whereas those in the drilling fluids may be derived from subsurface fluids.Advances in our understanding of the origins, diversity, distributions, and functions of microorganisms in deep, often extreme, subsurface environments are rapidly expanding our knowledge of biogeochemical processes on Earth and beyond. The discovery of novel microorganisms in deep accessible subsurface habitats provides opportunities for discovering new pharmaceuticals, studying biosynthetic processes, remediating contaminated environments, and enhancing energy production. The major obstacles to understanding the subsurface biosphere have been our limited abilities to access the deep subsurface environment, to acquire uncontaminated samples, and to place our knowledge of microorganisms (functional genes and proteins) into an environmental context. Past and current opportunities to address biogeochemical processes have largely been limited to the shallow crust and geographically sparse locations (7,19,30,32). More recently, Onstott et al. (27) studied microbial diversity, abundance, and functions in the metamorphic quartzite and Carbon Leader from deep mines in South Africa. Despite the great caution taken, the authors demonstrated that the samples were still contaminated, but they were able to show that indigenous microorganisms w...

Economic concentrations of Fe^Ti oxides occur as massive, conformable lenses or layers in the lower part of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. Mineral chemistry, textures and QUILF equilibria indicate that oxides in rocks of the intrusion were subjected to extensive subsolidus re-equilibration and exsolution. The primary oxide, reconstructed from compositions of titanomagnetite in the ores and associated intergrowths, is an aluminous titanomagnetite (Usp 40 ) with 40 wt % FeO, 34 wt % Fe 2 O 3 , 16Á5 wt % TiO 2 , 5Á3 wt % Al 2 O 3 , 3Á5 wt % MgO and 0Á5 wt % MnO. This composition is similar to the bulk composition of the oxide ore, as inferred from whole-rock data. This similarity strongly suggests that the ores formed from accumulation of titanomagnetite crystals, not from immiscible oxide melt as proposed in earlier studies. The occurrence of oxide ores in the lower parts of the Panzhihua intrusion is best explained by settling and sorting of dense titanomagnetite in the ferrogabbroic parental magma. This magma must have crystallized Fe^Ti oxides relatively early and abundantly, and is likely to have been enriched in Fe and Ti but poor in SiO 2 . These features are consistent with fractionation of mantle-derived melts under relatively high pressures ($10 kbar), followed by emplacement of the residual magma at $5 kbar. This study provides definitive field and geochemical evidence that Fe^Ti oxide ores can form by accumulation in ferrogabbro. We suggest that many other massive Fe^Ti oxide deposits may have formed in a similar fashion and that high concentrations of phosphorus or carbon, or periodic fluctuation of fO 2 in the magma, are of secondary importance in ore formation.

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