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The rise of Na‐storage devices has put forward higher requirements for Na‐storage anode materials with large capacity, long service life, and fast rate capability. Mesoporous carbons, either as active materials or as hosts for guest active nanoparticles, are considered as promising electrode materials. However, addressing the issues of their short lifespan resulting from volume variation and the low coulombic efficiency caused by large surface area via a facile porous structure design still remains a challenge. Herein, a versatile phosphorus‐doped mesoporous carbon (PMC) armed is developed by graphene aerogel (GA) (GA@PMC) for hosting Na‐storage active nanoparticles. As a case study, FeSe2 nanoparticles are selectively supported onto this GA@PMC matrix, creating the FeSe2/GA@PMC composite. When employed in typical Na‐storage devices, such as Na‐ion batteries, Na‐ion hybrid capacitors, and Na‐ion based dual‐ion batteries, the FeSe2/GA@PMC electrode consistently demonstrates superior electrochemical performance. In such GA@PMC, the conformal GA can improve the entire conductivity while decreasing the specific surface area that is directly contacting with electrolyte. The interconnected macroporous structure can not only promote the diffusion of Na+ but also buffers the volume change of the guest active nanoparticles. This bespoke carbon platform synergistically endows the electrode material with enhanced rate capability, cyclic stability, and coulombic efficiency, which are being expected in advanced Na‐storage devices. [ABSTRACT FROM AUTHOR]

A strategy for the synthesis of N,N‐disubstituted hydrazines via the electrocatalytic addition of hydrazine to α,β‐unsaturated carbonyl compounds is reported. The reaction was carried out under constant current electrolytic conditions in an undivided cell. Using this methodology, various N,N‐disubstituted hydrazines were prepared in 57–94% yield in 40 minutes. By adding cyclohexanone and acetic acid to the reaction mixture of N,N‐disubstituted hydrazines and heating for 2 hours, a one‐pot synthesis of N‐substituted indoles was also developed. Furthermore, based on cyclic voltammetry and control experiments, a plausible mechanism involving a radical pathway is proposed. [ABSTRACT FROM AUTHOR]

Widespread integration of carbon‐based membranes into prevailing fields like energy storage and material engineering is thwarted by a lack of functionality, customization, and compatibility, making the development of such carbon‐based membranes urgency yet challenging. Herein, a "graphene bubble bridging" strategy is adopted to fabricate the multifunctional carbon fiber membrane, in which graphene bubbles with optimized assembling not only endow the carbon fiber with superior flexibility and integrity by embedded bridging function, but also enhance the fast electron transport capability and electrolyte wettability. Few‐layer MoSSe nanosheets with expanded interlayer spacing as a typical energy storage material contribute to plentiful ion intercalation/deintercalation that can be well buffered within the robust fibers. The interlaced carbon fibers enable a self‐supporting framework that ensures good conductivity and mechanical stability as well. Such functional, customized, and compatible membranes with synergies can boost the attributes of advanced K+ storage devices, such as flexible K‐ion capacitors and K‐based dual‐ion batteries. This work can afford new insights for designing flexible electrode in the energy storage field, as well as various types of conformations that can bring more opportunities on developing flexible functional membranes for other fields (e.g., catalysts, electromagnetic shielding). [ABSTRACT FROM AUTHOR]

The Susong complex zone is a relatively low‐grade metamorphic unit located in the southern part of the Dabie orogen and preserves a variety of metasedimentary rocks, mostly with epidote–amphibolite facies. However, their depositional age, provenance and tectonic setting of sedimentary protolith remain controversial due to the lack of fossils, precise dating and integrated geochemical investigation. This study has conducted whole‐rock elemental, and zircon U‐Pb SHRIMP dating and Lu‐Hf isotope analyses on three types of representative metasedimentary rocks including garnet‐bearing mica‐quartz schist, graphite‐muscovite‐quartz schist and dolomitic marble from the Susong complex zone. The U‐Pb SHRIMP dating data indicate that the sedimentary protolith of these rocks have the maximum depositional ages of less than 840–750 Ma and have various sedimentary provenances. In combination with zircon Lu‐Hf isotope compositions, the provenance of the metasedimentary rocks in the region is for the first time documented to be mainly derived from four groups of magmatic rocks formed at ∼2.5 Ga, ∼2.0 Ga, ∼1.4 Ga and ∼0.8 Ga in response to four episodes of igneous activity in the northeastern margin of the Yangtze Block. The conventional geothermobarometry combined with rare metamorphic zircon ages indicate that the studied rocks underwent the Late Triassic continental subduction‐related metamorphism with peak epidote–amphibolite facies conditions at P = 0.34–0.91 GPa and T = 427–532°C. In addition, results of the elemental contents (i.e., La, Ce, Th and ΣREE) and ratios (i.e., Eu/Eu* and LaN/YbN) suggest that the protoliths of the metasedimentary rocks were mainly shales, wackes and limestones, most probably related to the Rodinia supercontinent rifting along the northern margin of the Yangtze Block during the Neoproterozoic. [ABSTRACT FROM AUTHOR]

The yield and quality of tomatoes (Solanum lycopersicum) is seriously affected by Phytophthora infestans. The long non‐coding RNA (lncRNA) Sl‐lncRNA39896 is induced after P. infestans infection and was previously predicted to act as an endogenous target mimic (eTM) for the microRNA Sl‐miR166b, which function in stress responses. Here, we further examined the role of Sl‐lncRNA39896 and Sl‐miR166b in tomato resistance to P. infestans. Sl‐miR166b levels were higher in Sl‐lncRNA39896‐knockout mutants than in wild‐type plants, and the mutants displayed enhanced resistance to P. infestans. A six‐point mutation in the region of Sl‐lncRNA39896 that binds to Sl‐miR166b disabled the interaction, suggesting that Sl‐lncRNA39896 acts as an eTM for Sl‐miR166b. Overexpressing Sl‐miR166b yielded a similar phenotype to that produced by Sl‐lncRNA39896‐knockout, whereas silencing of Sl‐miR166b impaired resistance. We verified that Sl‐miR166b cleaved transcripts of its target class III homeodomain‐leucine zipper genes SlHDZ34 and SlHDZ45. Silencing of SlHDZ34/45 decreased pathogen accumulation in plants infected with P. infestans. Additionally, jasmonic acid and ethylene contents were elevated following infection in the plants with enhanced resistance. Sl‐lncRNA39896 is the first known lncRNA to negatively regulate resistance to P. infestans in tomato. We propose a novel mechanism in which the lncRNA39896–miR166b–HDZ module modulates resistance to P. infestans. [ABSTRACT FROM AUTHOR]

Carbonaceous materials have been usually adopted as the anode for high energy density potassium‐ion hybrid capacitors (KICs) owing to their low voltage plateau, high conductivity, and excellent electrochemical compatibility. The improvements of their specific capacity and sluggish intercalation mechanism are still challenges to further boost the energy density of KICs while maintaining high power density and long cycle life. Herein, a N‐doped mesoporous carbon sphere array composite is developed by a dual‐templates method. The N‐doped carbon sphere array with interpenetrated macro‐ and meso‐pores facilitates the fast electron transport and rapid K+ diffusion. The uniformly introduced Co3O4 nanoparticles (NPs) confined in the array enable a kinetically boosted conversion reaction for excess and fast K+ storage. The partially oxidized Co NPs can efficiently enhance the conductivity of the entire composite. By introducing this optimized conversion capacity from encapsulated Co3O4 NPs, the composite with intercalation and conversion coupling mechanisms displays superior capacity and cycle life. The assembled KICs exhibit high energy/power densities (148 Wh kg−1/124 W kg−1) and great cycling performance (94% after 5000 cycles, 0.5 A g−1). This promising strategy demonstrates an example for carbonaceous composite anode with synergistic K+ storage hybrid mechanism toward high performance KICs. [ABSTRACT FROM AUTHOR]

Herein, nitrogen‐doped ordered hierarchical porous carbon (N‐OHPC) is fabricated via a templating method by applying silica colloidal crystal as template and polypyrrole (PPy) as carbon source. The as‐prepared N‐OHPC possesses ordered interconnected macropores, rich mesopores and large BET surface area (825.6 m2 g−1). Pt/N‐OHPC is then prepared by depositing Pt nanoparticles (19.3 wt%) on N‐OHPC as catalyst towards methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). The Pt/N‐OHPC containing small and uniform Pt nanoparticles (∼1.7 nm) exhibits good electrocatalytic performance and better durability for MOR and ORR than the commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

We present a new and easy‐to‐implement sequential sampling method for Carr–Geman–Madan–Yor (CGMY) processes with either finite or infinite variation, exploiting the time change representation of the CGMY model and a decomposition of its time change. We find that the time change can be decomposed into two independent components. While the first component is a finite generalized gamma convolution process whose increments can be sampled by either the exact double CFTP ("coupling from the past") method or an approximation scheme with high speed and accuracy, the second component can easily be made arbitrarily small in the L1 sense. Simulation results show that the proposed method is advantageous over two existing methods under a model calibrated to historical option price data. [ABSTRACT FROM AUTHOR]

Abstract: A novel three‐dimensionally (3D) ordered mesoporous polypyrrole (OMPPy) is successfully synthesized through a facile chemical polymerization using silica nanosphere arrays as hard templates. The resulting OMPPy possesses a large BET surface area (270.9 m2 g−1), 3D interconnected large mesopores (∼32 nm), and small mesopores (2‐4 nm) on the large mesopore walls. The OMPPy is then applied as a host to form a kind of sulfur/OMPPy (S/OMPPy) composite cathode through a solution method followed by a heat‐treatment process. Electrochemical test results show that the developed S/OMPPy cathode containing 51.1 wt% sulfur is able to deliver a high and stable specific discharge capacity of 908 mAh g−1 at 0.1C after 100 cycles. At higher discharge rates of 1C, the S/OMPPy exhibits a discharge capacity of 673.7 mAh g−1 after 100 cycles and 462.2 mAh g−1 after 300 cycles. The exceptional electrochemical performance of the S/OMPPy is attributed to the large surface area and the commendable pore size distribution of OMPPy for trapping polysulfides as well as the ordered large mesopores for excellent electrolyte accessibility and fast Li‐ion transport. [ABSTRACT FROM AUTHOR]

Abstract: We measured the electrical resistivity of iron, Fe99C1, Fe3C, and Fe7C3 up to ~80 GPa using the van der Pauw method in a diamond anvil cell. The electrical resistivity of disordered Fe99C1 at high pressure shows a strong impurity resistivity of carbon. The ferromagnetic‐paramagnetic transition in Fe3C and Fe7C3 is associated with the flattening of the resistivity pressure gradient at ~6 GPa. Fe7C3 exhibits the highest electrical resistivity among all iron‐light element alloys, and Fe3C and Fe7C3 disobey the Matthiessen's rule by showing a lower electrical resistivity than a disordered iron‐carbon alloy because of chemical ordering. A comparison of the impurity resistivity between silicon, sulfur, nickel, and carbon shows that carbon has an exceedingly stronger alloying effect than other elements. If the chemical ordering observed in Fe‐Si system is held true for the Fe‐C system, the chemical ordering in Fe7C3 possibly increases the thermal conductivity of the inner core and enlarges the thermal and electrical conductivity gap at the inner‐core boundary. Models of the thermal conductivity of liquid Fe70C30 with 8.4 wt % carbon show a low thermal conductivity of 38 Wm−1 K−1 at the pressure‐temperature conditions of the topmost outer core. The corresponding heat flow of 6 TW at the core‐mantle boundary is notably lower than previous electrical resistivity results on Fe and Fe alloys. The alloying effect of carbon on the electrical and thermal conductivity of iron can thus play a significant role in understanding the heat flux at the core‐mantle boundary and the thermal evolution of the core. [ABSTRACT FROM AUTHOR]

A one-step template-based technique for the fabrication of three dimensionally ordered macroporous carbon (3DOMC) was developed. 3DOMC, prepared using silica crystal as a template and soluble resol as a carbon source, possesses ordered macropores with mesoporous walls. ZnO nanoparticles were deposited on as-prepared 3DOMC via a simple in situ growth process to form a ZnO/3DOMC anode material for lithium-ion batteries. In the composite, the ZnO nanoparticles (≈3.9 nm) were well-dispersed on the walls of 3DOMC. The ZnO/3DOMC anode exhibited an enhanced performance in a lithium battery delivering a specific capacity of 673 mAh g−1 at a current density of 0.1 C (0.1 C=97.8 mA g−1) after 300 cycles. This superior performance was ascribed to the ordered interconnected macropores of 3DOMC which could provide rapid diffusion paths for lithium-ion diffusion and the electrolyte penetration, and buffer the volume changes of the ZnO nanoparticles upon cycling. Furthermore, the mesoporous structure of the 3DOMC walls could enhance the wettability of the ZnO-based electrode, further improving its electrochemical performance. [ABSTRACT FROM AUTHOR]

The drag-reducing characteristics in the turbulent channel flow of dilute cationic surfactant solution, cetyltrimethyl ammonium chloride (CTAC)/sodium salicylate (NaSal) aqueous solution, were experimentally investigated in a closed loop fluid flow facility at different temperatures. The mass concentrations of the surfactant solution ranged from 75 to 200 ppm, and the temperatures ranged from 15 to 55°C. The cationic surfactant solution showed a great drag-reducing ability, which was greatly affected by concentration, temperature, and Reynolds number. It was found that there existed a critical temperature Tc in each solution at different concentrations. Above Tc, drag-reduction level decreases and reaches the behaviour of water flow without drag-reducing ability. A new temperature parameters Tf, was proposed, and the difference between Tc and Tf can represent the effective temperature range for the drag reduction at a certain Reynolds number. The variation tendency of Tf and Tc with Reynolds numbers can give the guidance of selecting effective drag reduction range to the practical application in the district heating systems (DHS). It was supposed that temperature and shear stress are two kind of energy applied on the surfactant microstructure, which can be helpful to the surfactant network formation or dissociation depending on their values. © 2011 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Silver-Catalyzed Radical Phosphonofluorination of Unactivated Alkenes" by C. Zhang and others, published in the periodical "Journal of the American Chemical Society" in 2013.