Silicified microfossils preserved in chert nodules of the Doushantuo Formation in the Yangtze Gorges area of South China have great potential to improve the biostratigraphic subdivision and correlation of the Ediacaran System. This potential can be realized only if solid taxonomy is available. However, a systematic treatment of these microfossils (particularly acanthomorphic acritarchs) is lacking, greatly limiting their biostratigraphic potential. This paper presents the systematic paleontology of silicified microfossils from upper Doushantuo Formation (Member III) chert nodules at three sections in the Yangtze Gorges area. More than 90 species of microfossils are described, including 66 named taxa of acanthomorphs, seven named taxa of sphaeromorphs, 12 taxa of cyanobacterial filaments and coccoids, four taxa of algal thalli, and two species of tubular microfossils. Several acritarch species, includingAppendisphaera clavan. sp.,Mengeosphaera grandispinan. sp.,M. stegosauriformisn. sp.,Leiosphaeridia, and possiblySinosphaera rupina, are shown to be multicellular organisms, consistent with the proposition that some Ediacaran acritarchs may be diapause eggs of early animals. This study supports the view that theTianzhushania spinosaacanthomorph biozone is unique to the lower Doushantuo Formation in South China (and perhaps its equivalent in northern India) and that Ediacaran acanthomorph assemblages from Australia, Siberia, and East European Platform are younger than theTianzhushania spinosabiozone. It is proposed that the first occurrence ofHocosphaeridium anozos, a species with easily recognizable morphology and wide taphonomic and geographic distributions, be used to define the second Doushantuo acanthomorph biozone succeeding theTianzhushania spinosabiozone. New taxa described in this paper include three new genera (Bispinosphaeran. gen.;Yushengian. gen.; andGranitunican. gen.) and 40 new species:Appendisphaera?brevispinan. sp.,A. clavan. sp.,A.?hemisphaerican. sp.,A. longispinan. sp.,A. setosan. sp.,Bispinosphaera peregrinan. gen. n. sp.,Crinita paucispinosan. sp.,Ericiasphaera densispinan. sp.,Hocosphaeridium dilatatumn. sp.,Knollisphaeridium denticulatumn. sp.,K. longilatumn. sp.,K. obtusumn. sp.,K. parvumn. sp.,Mengeosphaera angustan. sp.,M. bellulan. sp.,M.cf.bellulan. sp.,M. constrictan. sp.,M.?cuspidatan. sp.,M.?gracilisn. sp.,M. grandispinan. sp.,M. latibasisn. sp.,M. miniman. sp.,M. spicatan. sp.,M. spinulan. sp.,M. stegosauriformisn. sp.,M. triangularisn. sp.,M. uniformisn. sp.,Sinosphaera asteriformisn. sp.,Tanarium acusn. sp.,T. elegansn. sp.,T. longitubularen. sp.,T.?minimumn. sp.,T. obesumn. sp.,T. variumn. sp.,Urasphaera fungiformisn. sp.,U. nuptan. sp.,Yushengia ramispinan. gen. n. sp.,Granitunica mcfaddeniaen. gen. n. sp.,Osculosphaera arcelliformisn. sp., andO. membraniferan. sp.

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Hydrogen generation by electrocatalysis water splitting is considered as one of the most promising techniques to address the energy crisis and environmental pollution. Highly efficient, low-cost, and stable catalysts are crucial to speed sluggish kinetics of the hydrogen evolution reaction (HER). Molybdenum disulfide has been considered to be a promising substitute to Pt-based materials, but its inherently low conductivity, finite active edge sites due to the thermodynamically stable basal plane, and the self-stacking and agglomeration properties still impede the HER activity. In addition, optimization of the electrode structure is equally critical for industrial high-rate hydrogen production. Herein, on the basis of the system engineering concept, we report a manganese-doped MoS2 ultrathin nanosheet anchoring on a fin-tube-like hierarchical carbon skeleton vertically to achieve the synergistic optimization of intrinsic activity and electrode architecture. The superhydrophilic and superaerophobic electrode with conductive carbon nanoarray structure can accelerate the mass transport (gas bubbles and electrolyte) and electron transfer processes. In addition, theoretical calculation reveals that all the hydrogen adsorption free energies of basal planes, S-edge, and Mo-edge for doped MoS2 have decreased. Moreover, the electronic structure of the Mn-doped MoS2 monolayer shows the absence of band gap, indicating improved inherent conductivity. This finely crafted self-supported binder-free electrode with integrated architecture shows a low overpotential of 130 mV at −10 mA/cm2, a Tafel slope as low as 44 mV/dec, and excellent durability even at a high cathodic current density of 200 mA/cm2 in 0.5 M H2SO4. This system engineering optimizing strategy may pave the way for the design of commercially available electrocatalysts.

For the first time, a FRET nanosensor for AA was developed using GQDs as the energy donors and SQA-iron(iii) as the energy acceptors.

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