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Estimating clean seismic signals from noisy single‐channel records is a hot research topic in the field of microseismic data processing. Due to the existence of strong random noise, the signal‐to‐noise ratio of such data is low, presenting a challenge for signal restoration. In this paper, we propose a denoising method of microseismic data based on a single‐channel phase space reconstruction and independent component analysis algorithm. Specifically, we first apply the phase space reconstruction to transform the one‐dimensional seismic signal into a high‐dimensional phase space in which signal and noise have different trajectories. We then employ independent component analysis to the reconstructed data for noise separation. Experimental results on real microseismic data verify that our proposed denoising method is useful for noise suppression and can enhance the signal‐to‐noise ratio of data, which can be further used for signal identification and event positioning in microseismic monitoring. [ABSTRACT FROM AUTHOR]

Apple stem pitting virus is a species in the genus Foveavirus in the family Betaflexiviridae. Apple stem pitting virus (ASPV) commonly infects apple and pear plants grown worldwide. In this study, by integrating bimolecular fluorescence complementation, split‐ubiquitin‐based membrane yeast two‐hybrid, and Agrobacterium‐mediated expression assays, the interaction relationships and the subcellular locations of ASPV proteins TGBp1–3 and CP in Nicotiana benthamiana leaf cells were determined. Proteins CP, TGBp1, TGBp2, and TGBp3 were self‐interactable, and TGBp2 played a role in the formation of perinuclear viroplasm and enhanced the colocalization of TGBp3 with CP and TGBp1. We found that the plant microfilament and endoplasmic reticulum structures were involved in the production of TGBp3 and TGBp2 vesicles, and their disruption decreased the virus accumulation level in the systemic leaves. The TGBp3 motile vesicles functioned in delivering the viral ribonucleoprotein complexes to the plasma membrane. Two cysteine residues at sites 35 and 49 of the TGBp3 sorting signal were necessary for the diffusion of TGBp3‐marked vesicles. Furthermore, our results revealed that TGBp1, TGBp2, and CP could increase plasmodesmal permeability and move to the adjacent cells. This study demonstrates an interaction network and a subcellular location map of four ASPV proteins and for the first time provides insight into the functions of these proteins in the movement of a foveavirus. [ABSTRACT FROM AUTHOR]

A multi‐stage core‐expansion method is proposed here as one component of the integrative binding‐site/extender/core‐expansion (BEC) strategy. The conceptual deconstruction of the partitioning ligand into three editable parts draws our focus onto progressive core expansion and allows the optimization of both acetylene uptake and selectivity. The effectiveness of this strategy is shown through a family of eight cationic pore‐partitioned materials containing three different partitioning ligands and various counter anions. The optimized structure, Co3‐cpt‐tph‐Cl (Hcpt=4‐(p‐carboxyphenyl)‐1,2,4‐triazole, H‐tph=(2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene) with the largest surface area and highest C2H2 uptake capacity (200 cm3/g at 298 K), also exhibits (desirably) the lowest CO2 uptake and hence the highest C2H2/CO2 selectivity. The successful boost in both C2H2 capacity and IAST selectivity allows Co3‐cpt‐tph‐Cl to rank among the best crystalline porous materials, ionic MOFs in particular, for C2H2 uptake and C2H2/CO2 experimental breakthrough separation. [ABSTRACT FROM AUTHOR]

We report here a one‐step method for synthesizing multi‐component and in‐situ‐formed homochiral spiroborate‐ester‐based metal‐organic framework CPM‐B1. This unique material successfully integrates COF fragment spiroborate ester within the MOF and simultaneously incorporate homochirality and helicity. In addition, CPM‐B1 is a rare example of framework materials that results from the cooperative assembly of three charge‐complementary cations: +1 (lithium), +2 (cobalt), and +3 (boron). The sophistication of the co‐assembly is further highlighted by the three structural roles of lithium ions. This unique structure contributes to its multi‐functional properties such as ionic conductivity and catalytic activity for oxygen reduction reaction (by CPM‐B1 carbonized material) and provides a new path to develop MOF materials with complex secondary building units and multi‐functional applications. [ABSTRACT FROM AUTHOR]

Nonprecious transition metal‐organic frameworks (MOFs) are one of the most promising precursors for developing electrocatalysts with high porosity and structural rigidity. This study reports the synthesis of high efficiency electrocatalysts based on S‐doped NiFeP. MOF‐derived S‐doped NiFeP structure is synthesized by a one‐step phosphorization process with using S‐doped MOFs as the precursor, which is more convenient and environment friendly, and also helps retain the samples' framework. The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance of the NiFeP catalysts can be improved after partially replacing P by S due to the tunable electronic structure. The optimized CCS‐NiFeP‐10 reaches a current density of 10 mA cm–2 for OER with an overpotential of 201 mV and outperforms most NiFe‐based catalysts. The S doping plays an important role in tuning the ΔG values for intermediates formation in Ni atoms to a suitable value and exhibits a pronouncedly improved the OER performance. CCS‐NiFeP‐20 sample presents excellent HER performance due to the d‐band center downshifting from the Fermi level. When the voltage of the electrolytic cell is 1.50 V, a current density of 10 mA cm–2 can be obtained. This strategy paves the way for designing highly active none‐noble metal catalysts. [ABSTRACT FROM AUTHOR]

We report here a strategy for making anionic pacs type porous materials by combining pore space partition with charge reallocation. The method uses the first negatively charged pore partition ligand (2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene, H‐tph) that simultaneously enables pore partition and charge reallocation. Over two dozen anionic pacs materials have been made to demonstrate their excellent chemical stability and a high degree of tunability. Notably, Ni3‐bdt‐tph (bdt=1,4‐benzeneditetrazolate) exhibits month‐long water stability, while CoV‐bdt‐tph sets a new benchmark for C2H2 storage capacity under ambient conditions for ionic MOFs. In addition to tunable in‐framework modules, we show feasibility to tune the type and concentration of extra‐framework counter cations and their influence on both stability and capability to separate industrial C3H8/C3H6 and C6H6/C6H12 mixtures. [ABSTRACT FROM AUTHOR]

A novel cytorhabdovirus, tentatively named Actinidia virus D (AcVD), was identified from kiwifruit (Actinidia chinensis) in China using high‐throughput sequencing technology. The genome of AcVD consists of 13,589 nucleotides and is organized into seven open reading frames (ORFs) in its antisense strand, coding for proteins in the order N‐P‐P3‐M‐G‐P6‐L. The ORFs were flanked by a 3′ leader sequence and a 5′ trailer sequence and are separated by conserved intergenic junctions. The genome sequence of AcVD was 44.6%–51.5% identical to those of reported cytorhabdoviruses. The proteins encoded by AcVD shared the highest sequence identities, ranging from 27.3% (P6) to 44.5% (L), with the respective proteins encoded by reported cytorhabdoviruses. Phylogenetic analysis revealed that AcVD clustered together with the cytorhabdovirus Wuhan insect virus 4. The subcellular locations of the viral proteins N, P, P3, M, G, and P6 in epidermal cells of Nicotiana benthamiana leaves were determined. The M protein of AcVD uniquely formed filament structures and was associated with microtubules. Bimolecular fluorescence complementation assays showed that three proteins, N, P, and M, self‐interact, protein N plays a role in the formation of cytoplasm viroplasm, and protein M recruits N, P, P3, and G to microtubules. In addition, numerous paired proteins interact in the nucleus. This study presents the first evidence of a cytorhabdovirus infecting kiwifruit plants and full location and interaction maps to gain insight into viral protein functions. [ABSTRACT FROM AUTHOR]

For rare‐earth separation, selective crystallization into metal‐organic frameworks (MOFs) offers new opportunities. Especially important is the development of MOF platforms with high selectivity toward target ions. Here we report a MOF platform (CPM‐66) with low‐coordination‐number environment for rare‐earth ions. This platform is highly responsive to the size variation of rare‐earth ions and shows exceptional ion‐size selectivity during crystallization. CPM‐66 family are based on M3O trimers (M=6‐coordinated Sc, In, Er‐Lu) that are rare for lanthanides. We show that the size matching between urea‐type solvents and metal ions is crucial for their successful synthesis. We further show that CPM‐66 enables a dramatic multi‐fold increase in separation efficiency over CPM‐29 with 7‐coordinated ions. This work provides some insights into methods to prepare low‐coordinate MOFs from large ions and such MOFs could serve as high‐efficiency platforms for lanthanide separation, as well as other applications. [ABSTRACT FROM AUTHOR]

Introduction of pore partition agents into hexagonal channels of MIL‐88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4′‐dipyridylsulfide (dps) ligands. One third of open metal sites in the acs net are retained in pacs MOFs; two thirds are used for pore‐space partition. The Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐BDC form, BDC=1,4‐benzenedicarboxylate). These high uptake capacities are accomplished with low heat of adsorption, a feature desirable for low‐energy‐cost adsorbent regeneration. CPM‐733‐dps is stable and shows no loss of C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

Introduction of pore partition agents into hexagonal channels of MIL‐88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4′‐dipyridylsulfide (dps) ligands. One third of open metal sites in the acs net are retained in pacs MOFs; two thirds are used for pore‐space partition. The Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐BDC form, BDC=1,4‐benzenedicarboxylate). These high uptake capacities are accomplished with low heat of adsorption, a feature desirable for low‐energy‐cost adsorbent regeneration. CPM‐733‐dps is stable and shows no loss of C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

By introducing a compatible reducing agent (2‐ethylimidazole) into a mono‐micelle assembly process, we present a type of ordered mesoporous TiO2 microspheres that combines radially aligned mesostructure with Ti3+ defects in mesoporous frameworks. Such reductant acts as a building block of mesostructured frameworks and reduces Ti4+ in situ to generate defects during calcination, giving rise to the coexistence of bulk Ti3+ defects and an ordered mesostructure. The mesoporous TiO2 has both excellent mesoporosity (a high surface area of 106 m2 g−1, a mean pore size of 18.4 nm) and stable defects with an extended photoresponse. Such integration of unique mesoscopic architecture and atomic vacancies provide both effective mass transportation and enhanced light utilization, leading to a remarkable increase in H2 generation rate. A maximum H2 evolution rate of 19.8 mmol g−1 h−1 can be achieved, along with outstanding stability under solar light. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs) are traditionally synthesized solvothermally by using cost‐ and waste‐incurring organic solvents. Here, a direct synthesis method is reported for ZIF‐8, ZIF‐67, and their heterometallic versions from solid precursors only. This solvent‐free crystallization method not only completely avoids organic solvents, but also provides an effective path for the synthesis of homogeneous mixed‐metal ZIFs. Furthermore, under templating by NaCl/ZnCl2 eutectic salt, carbonization of the ZIF materials gives rise to a series of N‐containing high‐surface‐area carbon materials with impressive catalytic properties for the oxygen reduction reaction. [ABSTRACT FROM AUTHOR]

We report a new magnesium metal–organic framework (MOF) (CPM‐107) with a special interaction with CO2. CPM‐107 contains Mg2‐acetate chains crosslinked into a 3D net by terephthalate. It has an anionic framework encapsulating ordered extra‐framework cations and solvent molecules. The desolvated form is closed and unresponsive to common gasses, such as N2, H2, and CH4. Yet, with CO2 at 195 K, it abruptly opens and turns into a rigid porous form that is irreversible via desorption. Once opened by CO2, CPM‐107 remains in the stable porous state accessible to additional gas types over multiple cycles or CO2 itself at different temperatures. The porous phase can be re‐locked to return to the initial closed phase via re‐solvation and desolvation. Such peculiar properties of CPM‐107 are apparently linked to a convergence of factors related to both framework and extra‐framework features. The unusual CO2 effect is currently the only available path to porous CPM‐107 which shows efficient C2H2/CO2 separation. [ABSTRACT FROM AUTHOR]

The introduction of a symmetry‐ and size‐matching pore‐partitioning agent in the form of either a molecular ligand, such as 2,4,6‐tri(4‐pyridinyl)‐1,3,5‐triazine (tpt), or a metal‐complex cluster, into the hexagonal channels of MIL‐88/MOF‐235‐type (the acs net) to create pacs‐type (partitioned acs) crystalline porous materials is an effective strategy to develop high‐performance gas adsorbents. We have developed an integrated COF–MOF coassembly strategy as a new method for pore‐space partitioning through the coassembly of [(M3(OH)1−x(O)x(COO)6] MOF‐type and [B3O3(py)3] COF‐type trimers. With this strategy, the coordination‐driven assembly of the acs framework occurred concurrently and synergistically with the COF‐1‐type condensation of pyridine‐4‐boronic acid into a C3‐symmetric trimeric boroxine molecule. The resulting boroxine‐based pacs materials exhibited dramatically enhanced gas‐sorption properties as compared to nonpartitioned acs‐type materials and are among the most efficient NH3‐sorption materials. [ABSTRACT FROM AUTHOR]

Abstract: An aqueous solution of Zn(NO3)2⋅6 H2O‐C6H2N4‐PEI and Zn(NO3)2⋅6 H2O‐CO(NH2)2 is used as the raw materials to fabricate hierarchically structured films of ZnO nanorods/nanosheets (ZnO NRs/NSs) via a two‐step hydrothermal synthesis. The films of ZnO NRs/NSs are then applied as photoanodes for application in dye‐sensitized solar cells (DSSCs). The current density–voltage curves and the incident monochromatic photon‐to‐electron conversion efficiency of DSSCs are measured. Using electrochemical impedance spectroscopy, intensity modulated photovoltage spectroscopy, and intensity modulated photocurrent spectroscopy, the conditions of the internal electron transport and transfer of ZnO‐based DSSCs are tested and analyzed. The results indicate that the ZnO NRs/NSs photoanodes have properties of rapid electron transport and high electron collection efficiency and show a relatively large amount of dye absorption. Therefore, for DSSCs based on ZnO NRs/NSs with liquid electrolyte, the short‐circuit current density (Jsc), open‐circuit voltage (Voc), fill factor (FF), and photoelectric conversion efficiency (PCE) are 11.82 mA cm−2, 0.66 V, 0.58, and 4.59 %, respectively. The PCE of the DSSCs is improved by 178.18 % compared to that of pure ZnO NRs cells (1.65 %) and is improved by 21.42 % with respect to pure ZnO NSs cells (3.78 %). [ABSTRACT FROM AUTHOR]

By integrating next-generation sequencing (NGS), bioinformatics, electron microscopy and conventional molecular biology tools, a new virus infecting kiwifruit vines has been identified and characterized. Being associated with double-membrane-bound bodies in infected tissues and having a genome composed of RNA segments, each one containing a single open reading frame in negative polarity, this virus shows the typical features of members of the genus Emaravirus. Five genomic RNA segments were identified. Additional molecular signatures in the viral RNAs and in the proteins they encode, together with data from phylogenetic analyses, support the proposal of creating a new species in the genus Emaravirus to classify the novel virus, which is tentatively named Actinidia chlorotic ringspot-associated virus (AcCRaV). Bioassays showed that AcCRaV is mechanically transmissible to Nicotiana benthamiana plants which, in turn, may develop chlorotic spots and ringspots. Field surveys disclosed the presence of AcCRaV in four different species of kiwifruit vines in five different provinces of central and western China, and support the association of the novel virus with symptoms of leaf chlorotic ringspots in Actinidia. Data on the molecular features of small RNAs of 21-24 nucleotides, derived from AcCRaV RNAs targeted by host RNA silencing mechanisms, are also reported, and possible molecular pathways involved in their biogenesis are discussed. [ABSTRACT FROM AUTHOR]

The structure of polyacrylonitrile-based prestabilized fibers and partially carbonized fibers prepared in air and nitrogen were studied by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD), the thermal properties were measured by differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA), and the mechanical properties and corrosion properties resistant to concentrated sulfuric acid are also tested. Oxygen functional groups form in the fibers prestabilized in air, providing active sites for dehydrogenation and intermolecular crosslinked reactions, which facilitates the formation of turbostratic graphite structure in partially carbonized fibers. The fibers prestabilized in nitrogen and their corresponding partially carbonized fibers are brittle feature, and have comparatively low tensile strength and elongation. The fibers prestabilized in air did not change the color of concentrated sulfuric acid until being etched in it for 6 h; by contrast, the fibers prestabilized in nitrogen were dissolved out only within 1 min. It indicates that the former has better chemical stability than the latter. The present work provides direct evidence that oxygen containing structure in prestabilized fibers is an essential precondition for obtaining high property carbon fibers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The article presents a study on the copolymerization of itaconic acid (IA) with acrylonitrile (AN) in an aqueous deposited copolymerization system. It cites IA as one comonomer that enhances the hygroscopicity of polyacrylonitrile (PAN) polymers as well as contributes to the formation of special high-performance acrylic fibers. Findings suggest the benefit of IA introduction into the polymerization system to preoxidation. It adds that the exothermic figure of the exotherms increases with IA.

Introduction of pore partition agents into hexagonal channels of MIL‐88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4′‐dipyridylsulfide (dps) ligands. One third of open metal sites in the acs net are retained in pacs MOFs; two thirds are used for pore‐space partition. The Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐BDC form, BDC=1,4‐benzenedicarboxylate). These high uptake capacities are accomplished with low heat of adsorption, a feature desirable for low‐energy‐cost adsorbent regeneration. CPM‐733‐dps is stable and shows no loss of C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

Introduction of pore partition agents into hexagonal channels of MIL‐88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4′‐dipyridylsulfide (dps) ligands. One third of open metal sites in the acs net are retained in pacs MOFs; two thirds are used for pore‐space partition. The Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐BDC form, BDC=1,4‐benzenedicarboxylate). These high uptake capacities are accomplished with low heat of adsorption, a feature desirable for low‐energy‐cost adsorbent regeneration. CPM‐733‐dps is stable and shows no loss of C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]