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Semiconducting single‐walled carbon nanotubes (sc‐SWCNTs) are promising candidates for constructing high‐performance fully printed flexible thin film transistors (TFTs) and circuits. How to achieve highly dense and uniform SWCNT thin films on different substrates has become a key scientific issue for printed flexible carbon‐based electronics. In this work, a universal method to efficiently immobilize conjugated polymer‐sorted sc‐SWCNTs on different substrates using solution‐processable SiO2 thin film as the adhesion layer is developed. Fully printed top‐gate SWCNT TFTs are successfully constructed by combining aerosol jet and inkjet printing using silver electrodes and ionic liquid‐cross‐linkable‐poly(4‐vinylphenol) as metal contact electrodes and dielectrics, respectively. Consequently, the fully printed paper‐based SWCNT TFTs represent extraordinary mechanical flexibility and good electrical properties with high on/off ratio (higher than 105), small subthreshold swing (≈70 mV dec−1), and small hysteresis, as well as high carrier mobility (up to 10.8 cm2 V−1 s−1) at low gate voltages (±1 V). In addition, the resistor‐loaded fully printed paper‐based inverters are also achieved using printed carbon nanotube conductive lines as the loaded resistors, exhibiting relatively large gains (16 at VDD of 1 V) and excellent mechanical flexibility. This work represents an encouraging advancement toward the practical applications of SWCNTs for high‐performance, low‐cost, and eco‐friendly paper‐based electronics. [ABSTRACT FROM AUTHOR]

The North Qaidam is an Early Paleozoic UHP metamorphic belt located at the north margin of the Tibet plateau. Eclogites in this belt contain both continental‐and oceanic‐type ones. In which, the continental‐type eclogites have protolith ages of 750–850 Ma and WPB or CFB geochemical signatures and are believed to have formed in a continental rift or an incipient oceanic basin setting related to the breakup of the Rodinia supercontinent, their metamorphic ages (421–458 Ma) and P–T paths are comparable to their host gneisses; oceanic‐type eclogites have cumulate gabbro or E‐MORB geochemical signatures, their protolith and metamorphic ages are 510–516 Ma and 425–450 Ma, respectively(Zhang et al., 2008). Therefore, the North Qaidam UHP belt was thought to record the whole Neoprotoerozoic–Paleozoic Wilson cycle (Song et al., 2014). In this study, we reported three new kinds of eclogites: kyanite‐bearing eclogite, lawsonite pseudomorph‐bearing eclogite and double mineral eclogite. They occur as big lentoid blocks in regional granitic gneiss in the western part of the belt. Phase equilibrium modelling and zircon LA‐ICPMS U‐Pb dating show that all these three eclogites experienced a clockwise P–T path with peak metamorphic conditions close to or fall in the coesite stability field, and their peak metamorphic age were around 436‐439 Ma, similar to those continental‐type eclogites in this belt. But their protolith ages are between 1273 and 1070 Ma, and some of them recorded an amphibolite facies metamorphic age of 927 Ma, and geochemical data and zircon Lu‐Hf and O isotope analysis indicate these eclogites have features of present day N‐MORB. Combined with the existing results, we propose that the North Qaidam is a polycyclic composite orogenwhich recorded tectonic evolution of Mesoproterozoic ocean floor spreading, assembly and breakup of Rodinia supercontinent, Early Paleozoic oceanic deep subduction and subsequently continental deep subduction. [ABSTRACT FROM AUTHOR]

The North Qaidam orogenic belt (NQOB) lies at the northeast margin of Tibet Plateau, between the Qilian massif to the north and Qaidam massif to the south. It consists of predominantly gneisses and marbles with minor eclogite and garnet peridotite, and is known as an Early Paleozoic continental deep subduction ultrahigh pressure (UHP) metamorphic belt in northwest China. Recently some studies suggest that the NQOB experienced oceanic deep subduction prior to the continental deep subduction. However, the records of ocean events are rarely preserved because of the complex multi‐stage transformation. Therefore, whether the Early Paleozoic ocean exists and the formation, nature and evolution of the Early Paleozoic ocean in North Qaidam are still in controversies. In this contribution, we report a new discovered SSZ‐type ophiolite suite in Kaipinggou area, the western segment of the NQOB. The ophiolite is mainly composed of peridotite, gabbro, basalt, boninite, andesitic porphyrite and plagiogranite. In which, the basalt and homogeneous gabbro are both enriched in LILE and depleted in HFSE, and display flat or LREE‐depleted REE patterns, similar to the MORB‐like geochemical characteristics of fore‐arc basalts; the boninite exhibits characteristics of fore‐arc boninites with high Si and Mg, but low Ti and Ca contents; the andesitic porphyrite is enriched in LILE but depleted in HFSE, similar to island arc magmatic rocks. Rock assemblage and their geochemical characteristics suggest that this SSZ‐type ophiolite was formed in fore‐arc setting of intra‐oceanic arc. The plagiogranite is a low‐potassium tholeiite metaluminous granite with low trace elements contents, slight enrichment of LREE, depletion of HREE and positive Eu anomaly; combining with ∊Hf (t) values (13.8–17.1) of zircons, the plagiogranite could be originated from partial melting of gabbros. LA–ICP–MS zircon U–Pb dating yielded the crystallization ages of 535±2 Ma, 513±3 Ma and 510±3 Ma for two cumulate gabbros and one homogeneous gabbro, respectively, and a formation age of 492±8 Ma for the plagiogranite. All these data suggest the existence of an Early Paleozoic ocean in the North Qaidam, and the initial subduction of the oceanic slab occurred earlier than 535Ma. [ABSTRACT FROM AUTHOR]

The long prism/needle‐shaped polycrystalline quartz aggregates and square/parallelogram‐shaped singlephase quartz inclusions in omphacite and garnet of ultrahigh pressure eclogite were first discovered from the Jiangalesayi area, South Altyn UHP belt. Based on their morphology, these quartz inclusions are quartz paramorphs after stishovite. The minimum peak pressure of the eclogite is estimated to be >8–9 GPa at 800– 1000 °C based on the stability field of stishovite. This new evidence, together with previous stishovite exsolution microstructure in the gneiss from the same region, suggests an ultra‐deep subduction and exhumation of the South Altyn continental rocks to/from mantle depths in stishovite stability field. Evidence of ultra‐deep subduction of continental materials might be more common and diverse than previous thought. Exhumation of subducted continental rocks from≥300 km has been considered impossible because they are denser than mantle at these depths. How did the stishovite bearing continental rocks of the South Altyn exhumated? As we all know, the densities of stishovite (4.3 g/cm3) are much higher than coesite (2.9 g/cm3), and stishovite transforms into coesite with temperature increases. Density calculations were performed for subducted continental rocks along phase transition of stishovite to coesite, using the third‐order Birch‐Murnaghan equation of state based on mineral fractions obtained from experiments and Perple_X. The results show that the density of Siliceous rocks decrease remarkably, lower than the surrounding mantle in coesite stability field, whereas the density of Oligosiliceous and Silicon unsaturated rocks is higher than surrounding mantle. Thus, we propose that the thermal induced transformation could provide an initial driven force for the exhumation of ultra‐deep subducted silica‐enriched felsic continental rocks. Temperature increase could be derived from an increased geothermal gradient from convective mantle or mantle plume. Mafic to ultra‐mafic rocks and silica‐deficient rocks may be captured by the upwelling subducted continental rocks and exhumated together. [ABSTRACT FROM AUTHOR]

Agricultural production, rural areas, and farmers are three key aspects of agriculture related to sustainable economic and social development in China. Rural development is a process of multi-participation, which involves actors from governments, village committees, villagers, rural economic cooperatives, enterprises, financing institutions, and non-government organizations (NGOs). Based on social network analysis (SNA), this article analyzes the social network structures and characteristics of various actors in different stages of rural development in Yanhe village, Hubei Province, China. The results show that both the village committee and villagers have great influence on rural development; NGOs are the leaders of rural environmental improvement; village cooperatives are the promoters of rural economic development; enterprises are the accelerators of rural construction and development. The study outlines the rural development model in Yanhe village where the village committee is the leader and multiple forms of participation and cooperation are present; there are excellent partnerships and communication mechanisms among the participants. The endogenous and sustainable development model identified from Yanhe village is valuable for other villages in China to adopt. [ABSTRACT FROM AUTHOR]

The occurrence of outbreaks of Cronobacter strains causing necrotizing meningitis in China highlights the need for strain characterization and subtyping of this pathogenic species. A total of 43 Cronobacter isolates and five Enterobacteriaceae strains were used in this study. The strains were characterized using two molecular typing methods, including enterobacterial repetitive intergenic consensus sequence polymerase chain reaction ( ERIC- PCR) and sequence analysis of the gyrB gene. Genetic profiles of cluster analysis from these two molecular typing tests clearly showed that there was no close relationship between Cronobacter spp. and Enterobacteriaceae strains. Discriminatory index of ERIC- PCR typing for the 43 Cronobacter isolates and five Enterobacteriaceae strains was high ( D = 0.984) by Simpson's index of diversity based on the similarity value of more than 80% using Bio Numerics version 5.0. Sequence analysis of the gyrB gene was proven to be suitable for the phylogenetic analysis of the Cronobacter strains. These results demonstrate that ERIC- PCR combined with sequence analysis of the gyrB gene may be a reliable, rapid typing strategy for Cronobacter strains. Practical Applications Molecular typing of foodborne pathogenic bacteria has been shown as a useful tool for tracking the source of infection and detection of virulent strains, as well as for determining the geographical and host distribution of possible variants. ERIC- PCR provides rapid clustered results when a large number of Cronobacter spp. isolates need to be subtyped rapidly. Furthermore, partial sequence analysis of the gyrB gene was utilized to differentiate among the closely related isolates. The results of the current study suggest that ERIC- PCR in conjunction with the gyrB sequence analysis would provide a reliable and accurate typing strategy for Cronobacter spp. strains. This combination of techniques can be used as a rapid means of comparing Cronobacter spp. isolates for epidemiological investigations. [ABSTRACT FROM AUTHOR]

Soluble porous organic polymers (SPOPs) are currently the subject of extensive investigation due to the enhanced processability compared to insoluble counterparts. Here, a new concept for the construction of SPOPs is presented, which combines the unique topological structure of hyperbranched polymers with rigid building blocks. By using this facile, one‐step strategy, a class of novel SPOPs which possess surface areas up to 646 m2 g−1 have been synthesized. The extended π‐conjugated backbone affords the polymers bright fluorescence under UV irradiation. Interestingly, after dissolution in a suitable solvent that was slowly evaporated, the polymers retain a large extent of porosity. The SPOPs are potential candidates for gas storage and separation, photovoltaic, and biological applications. In particular, due to the presence of an internal porous structure and open conformations, they show high drug loading efficiency (1.91 g of ibuprofen per gram), which is considerably higher than conventional porous organic polymers. A new concept for the construction of soluble porous organic polymers (SPOPs) is presented via the combination of unique topological structure of hyperbranched polymers with rigid building blocks. The resulting SPOPs exhibit good porous and fluorescence properties no matter in solid or solution form, which is promising in separation, photovoltaic, and biomaterial field. [ABSTRACT FROM AUTHOR]