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Shuttling of lithium polysulfides and slow redox kinetics seriously limit the rate and cycling performance of lithium-sulfur batteries. In this study, Fe3O4-dopped carbon cubosomes with a plumber's nightmare structure (SP-Fe3O4-C) are prepared as sulfur hosts to construct cathodes with high rate capability and long cycling life for Li-S batteries. Their three-dimensional continuous mesochannels and carbon frameworks, along with the uniformly distributed Fe3O4 particles, enable smooth mass/electron transport, strong polysulfides capture capability, and fast catalytic conversion of the sulfur species. Impressively, the SP-Fe3O4-C cathode exhibits top-level comprehensive performance, with high specific capacity (1303.4 mAh g−1 at 0.2 C), high rate capability (691.8 mAh gFe3O41 at 5 C), and long cycling life (over 1200 cycles). This study demonstrates a unique structure for high-performance Li-S batteries and opens a distinctive avenue for developing multifunctional electrode materials for next-generation energy storage devices. Shuttling of lithium polysulfides and slow redox kinetics seriously limit the rate and cycling performance of lithium-sulfur batteries. Here, the authors report a Fe3O4 nanoparticle doped mesoporous carbon cathode with a plumber's nightmare structure that can achieve high-rate and long performance. [ABSTRACT FROM AUTHOR]

Hydrogel-based sensors commonly manifest pronounced swelling in aqueous milieus, a phenomenon that can precipitate deterioration of mechanical performance and distortion in output signals, thereby markedly constraining their expansive applicability. Drawing inspiration from the hierarchical heterogeneous cross-linking architecture inherent in biological tissues, an anti-swelling supramolecular hydrogel with robustness, fast self-recovery, and strain-sensitivity was meticulously engineered through leveraging the principles of multiple dynamic interaction matching. The heterogeneous structure for the hydrogels was constructed by integrating both 'rigid' carboxyl-Zr4+ coordination complexes and 'soft' hydrophobic micro-regions mediated by electrostatic interactions into the system. The synergistic interplay between reversible rigid and flexible cross-linking endowed the supramolecular hydrogels with robust mechanical properties, evidenced by a strength of 3.64 MPa, toughness of 6.83 MJ m−3, and complete self-recovery within 7 minutes, alongside anti-swelling capabilities in various aqueous environments, including acidic, alkaline, and saline solutions. Moreover, the hydrogels developed desirable sensing properties on account of the contribution of dynamic ions (Br−, Cl−, and Zr4+), enabling accurate signal output under diversified frequencies and strains. Consequently, these hydrogels were adapted to construct underwater sensors capable of transmitting information through Morse code. This bio-inspired design strategy achieved the perfect combination of mechanical, anti-swelling, and sensing properties in the hydrogels, offering novel insights into the fabrication of underwater sensors. [ABSTRACT FROM AUTHOR]

Woven silica fiber-reinforced ceramic silica matrix composites with 2.5 dimensionality (2.5D woven SiO2f/SiO2 CMCs) offer various advantages and are commonly utilized in the aerospace industry. The CMCs are primarily prepared using the sol–gel process including infiltration, drying, and sintering under a certain temperature for several cycles. The infiltration effect is influenced by the pore diameter distribution inside the silica matrix, the silica matrix geometry, porosity inside silica matrix, and the silica sol viscosity according to Washburn equation for capillary rise. The physical properties of fiber, matrix, and the interfacial properties are important factors for the mechanical performance of CMCs. The mechanical strength of the CMCs matrix can be enhanced by densification to increase the contact area between the silica fiber tows and silica matrix. Silica aerogels are prepared by proportioning different molar ratios of ethyl-cool orthosilicate, anhydrous ethanol, and deionized water. The porosity of CMCs specimens filled with silica aerogel is around 0.88-9.02%, which is lower than that of specimens without silica aerogel (20-25%). Therefore, woven SiO2f/SiO2 CMCs have a fill ratio of 90.98-99.12%. The compressive impact process was simulated with finite element analysis (FEA), and the split Hopkinson pressure bar (SHPB) compressive impact test for the CMCs specimens showed improvement in the anti-impact mechanical properties of CMCs. The densification effect on CMCs specimens filled with silica aerogel was examined and analyzed via SEM imaging. Upon comparison, the simulation results show good consistency with the experimental stress–strain curves and failure modes results, indicating that the compressive impact behaviors can be efficiently predicted with FEA. Kindly check and confirm whether the corresponding author and affiliation is correctly identified.it is ok [ABSTRACT FROM AUTHOR]

In this article, a preparation method of a water‐dispersible photoinitiator, which can be used for three‐dimensional (3D) printing of the hydrogel and can be initiated under visible light is proposed. The oil‐soluble photoinitiator 2,4,6‐trimethylbenzoyl‐diphenylphosphine oxide (TPO) is nano‐wrapped with surfactant Tween 20 to obtain the oil‐in‐water (O/W) miniemulsion, and then it is successfully transformed into water‐dispersible nanospheres without the use of organic solvents or crystallization inhibitors. The morphology and optical properties were characterized by transmission electron microscopy (TEM), particle size analysis and ultraviolet–visible (UV–Vis) spectroscopy. Subsequently, the water‐dispersible nano‐photoinitiator was used to realize the photopolymerization of acrylamide/N,N′‐methylenebisacrylamide hydrogel under visible light (405 nm). Then, the micromorphology of the photocuring process of the hydrogel was observed by TEM and the photocuring activity of the initiator was evaluated. Finally, a viscosifier suitable for AM/MBA hydrogel system was screened out, and the direct ink writing (DIW) 3D printing of the hydrogel was successfully realized by using this nano‐photoinitiator. [ABSTRACT FROM AUTHOR]

As the formaldehyde is one of the main indoor pollutants, the purpose of this study is to effectively remove indoor formaldehyde pollution by using environmentally friendly 3D printing ornaments. The wood 3D printing filaments cellulose/polylactic acid composite (Cellu/P) was selected as the starting material, and 3‐aminopropyltriethoxysilane (APTES) was used for chemical modification to obtain a series of cellulose composite materials with amino groups. The modified composite materials (APTES@Cellu/P) were characterized by Fourier transform infrared, X‐ray diffraction, scanning electron microscope, energy dispersive spectroscopy, thermogravimetric analysis, and mechanical tests, and a formaldehyde removal experiment was performed. The feasibility of 3D printing was evaluated, and the process of 3D printing‐functionalized customized ornaments was proposed, and then a school emblem was used for modeling, printing, and surface modification. Compared with the commercially traditional activated carbon, 3D printing‐customized ornaments of APTES@Cellu/P material has a better formaldehyde removal effect, and can even avoid the secondary pollution that is common to the activated carbon. [ABSTRACT FROM AUTHOR]

Graphite reinforced hollow epoxy macrospheres (GR-HEMS) and hollow glass microspheres (HGMS) were used to prepare three phase epoxy syntactic foam (ESF) using 'molding method', and the physical and mechanical properties of ESF were also studied and investigated. An innovative 'rolling ball method' was implemented in the GR-HEMS preparation process. The performance tests show that higher GR-HEMS stacking volume fraction, lower GR-HEMS thickness, higher GR-HEMS diameter, higher HGMS volume fraction, lower HGMS density are beneficial to reducing the density of ESF, but the effects of the five factors on the strength of ESF are the opposite. Therefore, in order to obtain 'high strength and low density' ESF composites, the various factors should be considered to achieve a balance of the strength and the density. Scanning electron microscope (SEM) shows that the 'rolling ball method' can make graphite form a graphite spherical x-y network throughout the macrosphere wall, which can make GR-HEMS and ESF have great compressive strength. The ESF (450 kg/m, 20.75 MPa) can withstand the 2075 meters water pressure and provide 550 kg/m buoyancy, which can give some advice to the preparation of buoyancy material used in deepwater oil exploration. [ABSTRACT FROM AUTHOR]

Abstract: Different crystal planes of CeO2 have a different number of broken bonds, surface energy and catalytic activities, so preparing the CeO2 with different exposed planes has attracted extensive attention. In recent years, the preparation of CeO2 nanocubes with {100} exposed plane has been a real hotspot of research because of its good catalytic performance. Based on the research about the alkali concentration, reaction temperature and reaction time, the formation mechanism of CeO2 nanocubes was explored. It is believed that the dissolution‐recrystallization process is accelerated in the condition of strong base, high temperature and high pressure. In other word, the Ostwald ripening process is strengthened, which is the decisive factor for the formation of CeO2 nanocubes. [ABSTRACT FROM AUTHOR]

3,13-Diglycidyloxypropyloctaphenyl double-decker silsesquioxane (3,13-diglydidyl DDSQ) was synthesized via hydrosilylation between 3,13-dihydrooctaphenyl double-decker silsesquioxane (3,13-dihydro DDSQ) and allyl glycidyl ether. This novel difunctional polyhedral oligomeric silsesquioxanes (POSS) macromer was incorporated into polybenzoxazine (PBZ) thermosets to obtain the organic-inorganic nanocomposites. Compared to control PBZ, the organic-inorganic nanocomposites displayed the enhanced glass transition temperatures ( Tg's). Under the identical condition, the organic-inorganic nanocomposites exhibited the stable rubbery plateaus in the measurements by dynamic mechanical thermal analysis, which was in marked contrast to control PBZ thermoset. The enhanced Tg's and improved dynamic mechanical properties are attributable to the formation of the additional crosslinking between PBZ and the difunctional POSS macromer and the nanoreinforcement of POSS cages on PBZ networks. Thermogravimetric analysis indicates that the organic-inorganic nanocomposites displayed improved thermal stability. POLYM. COMPOS., 38:827-836, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT In this contribution, we reported the synthesis of a series of POSS-terminated polycyclooctadiene (PCOD) telechelics via ring-opening metathesis polymerization (ROMP) approach. Toward this end, 1,4-diPOSS-but-2-ene was synthesized via copper-catalyzed Huisgen cycloaddition reaction (i.e., click chemistry); it was then used as a chain transfer agent (CTA) for the ROMP of cyclooctadiene. The ROMP was carried out with Grubbs second generation catalyst and the POSS-terminated PCOD telechelics with variable lengths of PCOD were obtained by controlling the molar ratios of CTA to cyclooctadiene. All the POSS-terminated PCOD telechelics in bulks were microphase-separated; the morphologies were quite dependent on the lengths of PCOD midchains. The POSS end groups can promote the crystallization of PCOD chains at room temperature, which was in marked contrast to the case of plain PCOD. Compared to the plain PCOD, the POSS-terminated PCOD telechelics displayed improved thermal stability and surface hydrophobicity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 223-233 [ABSTRACT FROM AUTHOR]

ABSTRACT In this contribution, we reported a facile synthesis of poly(methyl methacrylate)- block-poly( N-vinyl pyrrolidone) (PMMA- b-PVPy) diblock copolymers via sequential radical polymerizations mediated by isopropylxanthic disulfide (DIP). It was found that the radical polymerization of N-vinyl pyrrolidone (NVP) mediated by DIP was in a controlled and living manner. In contrast, the polymerization of methyl methacrylate mediated by DIP displayed the behavior of telomerization, affording xanthate-terminated PMMA with a good control of molecular weights while the conversion of monomer was not very high. The xanthate-terminated PMMA can be successfully used as the macromolecular chain transfer agent for the polymerization of NVP via RAFT/MADIX process and thus PMMA- b-PVPy diblock copolymers can be successfully synthesized via sequential radical polymerization mediated by isopropylxanthic disulfide. One of these diblock copolymers was incorporated into polybenzoxazine and the nanostructured thermosets were obtained as evidenced by transmission electron microscopy, small angle X-ray scattering, and dynamic mechanical thermal analysis. The formation of nanostructures in polybenzoxazine thermosets was ascribed to a reaction-induced microphase separation mechanism. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 952-962 [ABSTRACT FROM AUTHOR]

In this work, we investigated theeffect of topological structuresof block copolymers on the formation of the nanophase in epoxy thermosetscontaining amphiphilic block copolymers. Two block copolymers composedof poly(ε-caprolactone) (PCL) and poly(2,2,2-trifluoroethylacrylate) (PTFEA) blocks were synthesized to possess linear and star-shapedtopologies. The star-shaped block copolymer composed a polyhedraloligomeric silsesquioxane (POSS) core and eight poly(ε-caprolactone)-block-poly(2,2,2-trifluoroethyl acrylate) (PCL-b-PTFEA) diblock copolymer arms. Both block copolymers were synthesizedvia the combination of ring-opening polymerization and reversibleaddition–fragmentation chain transfer/macromolecular designvia the interchange of xanthate (RAFT/MADIX) process; they were controlledto have identical compositions of copolymerization and lengths ofblocks. Upon incorporating both block copolymers into epoxy thermosets,the spherical PTFEA nanophases were formed in all the cases. However,the sizes of PTFEA nanophases from the star-like block copolymer weresignificantly lower than those from the linear diblock copolymer.The difference in the nanostructures gave rise to the different glasstransition behavior of the nanostructured thermosets. The dependenceof PTFEA nanophases on the topologies of block copolymers is interpretedin terms of the conformation of the miscible subchain (viz. PCL) atthe surface of PTFEA microdomains and the restriction of POSS cageson the demixing of the thermoset-philic block (viz. PCL). [ABSTRACT FROM AUTHOR]

In this article, we report the preparation of crosslinked epoxy microspheres with diameters of 5-10 μm prepared via phase-inverted phase separation induced by polymerization in the thermosetting blend of epoxy and poly(ε-caprolactone). The surfaces of the epoxy microspheres were functionalized to bear 2-bromopropionyl groups, which were further used as initiators to obtain poly(glycidyl methacrylate) (PGMA) grafted epoxy microspheres via the surface-initiated atom transfer radical polymerization approach. The PGMA-grafted epoxy microspheres were then employed to react with 3-aminopropyltrimethoxylsilane (APTMS) to obtain the functionalized epoxy microspheres, the surface of which contained a great number of trimethoxysilane groups. A co-sol-gel process between the APTMS-functionalized epoxy microspheres and tetraethoxysilane was performed, and organic-inorganic glassy solids were obtained. The organic-inorganic glasses were used as precursors for accessing macroporous silica materials via pyrolysis at elevated temperatures. The hierarchical porosity of the resulting macroporous silica was investigated by means of field emission scanning electronic microscopy, transmission electronic microscopy, and surface-area Brunauer-Emmett-Teller (BET) measurements. We found that the macroporous silica possessed BET surface areas in the range 183.9-235.2 m2/g, depending on the compositions of their precursors. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Inthis contribution, we reported the investigation of the formationand confined crystallization behavior of polyethylene nanophases inepoxy thermosets. The nanostructured epoxy thermosets were preparedby the use of a poly(ε-caprolactone)-block-polyethylene-block-poly(ε-caprolactone) (PCL-b-PE-b-PCL) triblock copolymer. The crystalline midblock(viz. PE) of the triblock copolymer was prepared from an α,ω-diacetoxy-terminatedpolycyclooctadiene with the molecular weight as high as Mn= 11,000, which was synthesized via the ring-openingmetathesis polymerization (ROMP) of cyclooctadiene catalyzed by Grubbssecond generation catalyst. The formation of PE nanophases in epoxythermosets was evidenced with transmission electronic microscopy (TEM),small-angle X-ray scattering (SAXS) and dynamic mechanical thermalanalysis (DMTA). It was found that in the nanostructured thermosets,the spherical nanophases of PE with the size of 20–30 nm indiameter were dispersed into the continuous epoxy matrices. Wide angleX-ray diffraction (XRD) showed that the formation of PE nanophasesdid not alter the structure of PE crystals. The investigations ofisothermal and nonisothermal crystallization kinetics showed thatthe crystallization of PE in the nanostructured thermosets was ina confined manner and the confinement has been interpreted on thebasis of nanoscaled space, interdomain connectivity, and the cross-linkedstructures of epoxy matrices. [ABSTRACT FROM AUTHOR]

In this contribution, we reported the preparation of mesoporous silica with a reactive block copolymer as the porogenviasol-gel process. Firstly, poly(glycidyl methacrylate)-block-poly(ϵ-caprolactone)-block-poly(glycidyl methacrylate) triblock copolymer (PGMA-b-PCL-b-PGMA) was synthesized with the combination of ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. Thereafter, the triblock copolymer was functionalizedviaits reaction with 3-aminopropyltriethoxysilane (APTES) to afford a new reactive block copolymer bearing triethoxysilane moieties. The latter was employed to perform the inter-component sol-gel reactions with tetraethoxysilane (TEOS) to obtain the organic-inorganic composites with various compositions. The organic-inorganic composites were subsequently used as the precursors to obtain the mesoporous silica materialsviapyrolysis at elevated temperatures. The surface-area Brunauer-Emmett-Teller (BET) measurements indicate that the materials of mesoporous silica with adjustable porosity have been successfully obtained. [ABSTRACT FROM PUBLISHER]

Amino-terminated poly(propylene oxide) (ATPPO) was incorporated into epoxy resin to toughen thermosets. It was found that nanostructured thermosets were obtained; the nanostructures were characterized by means of atomic force microscopy and small-angle X-ray scattering. The formation of the nanostructures is interpreted on the basis of the occurrence of the reaction of terminal groups of ATPPO with diglycidyl ether of bisphenol A; this reaction is suggested to result in the formation of star-shaped block copolymers composed of poly(propylene oxide) (PPO) and epoxy blocks. Due to the presence of the star-shaped block copolymer produced in situ, the phase separation of PPO induced by the reaction was confined to the nanometer scale. The glass-transition behavior and fracture toughness of the nanostructured thermosets were investigated by means of differential scanning calorimetry, dynamic mechanical thermal analysis, and the measurement of critical stress intensity factors. The epoxy thermosets were significantly toughened by the inclusion of a small amount of ATPPO. The thermal and mechanical properties of the nanostructured thermosets are compared to the binary blends of epoxy resin containing hydroxyl-terminated poly(propylene oxide) (HTPPO) with identical molecular weight. With the identical composition, the nanostructured thermosets displayed higher fracture toughness than that of their binary blends. The difference in morphology and properties is interpreted in terms of the formation of the nanostructures. [ABSTRACT FROM AUTHOR]

A series of triaxial compression tests of frozen sandy soil are carried out under five confining pressures (1 MPa, 4 MPa, 6 MPa, 8 MPa and 10 MPa) at –6 °C. By comparing the grain size distribution curves of frozen sandy soil before and after shearing, it is found that significant particle breakage can occur during triaxial shearing. Particle breakage changes internal structure of geomaterials and has a significant effect on their stress–strain relationships. In order to accurately describe the effect of particle breakage of frozen sandy soil on the stress–strain relationships, an elastoplastic constitutive model for frozen sandy soil considering particle breakage is proposed. Based on the energy balance equation established by Indraratna and Salim, the constant critical state stress ratio (Mcr) in the energy balance equation is modified to the stress ratio (M) which changed with shear strain during the shearing process. A yield function, considering particle breakage, is proposed using the modified energy balance equation. The hardening law is determined based on the rebound test results of frozen sandy soil, and the associated flow rule is adopted in the model. Compared with experimental data, the model can well simulate the stress–strain relationships under different confining pressures for frozen sandy soil. The particle breakage characteristics of frozen sandy soil are studied. The energy balance equation considering particle breakage is modified to calculate the energy dissipation of frozen sandy soil. An elastoplastic constitutive model for frozen sandy soil considering particle breakage is proposed. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is the second most common neurodegenerative disease, and mild cognitive impairment (MCI) is a well-established risk factor for the development of dementia in PD. A growing body of evidence suggests that low expression of glucocerebrosidase (GBA) promotes the transmission of α-synuclein (α-Syn) interpolymers and the progression of PD. However, how GBA mutations affect the pathogenesis of PD via abnormal aggregation of α-Syn is unclear, and no clinically valid PD-MCI genetic markers have been identified. Here, we first located a GBA eQTL, rs12411216, by analysing DHS, eQTL SNP, and transcription factor binding site data using the UCSC database. Subsequently, we found that rs12411216 was significantly associated with PD-MCI (P < 0.05) in 306 PD patients by genotyping. In exploring the relationship between rs12411216 and GBA expression, the SNP was found to be associated with GBA expression in 50 PD patients through qPCR verification. In a further CRISPR/Cas9-mediated genome editing module, the SNP was identified to cause a decrease in GBA expression, weaken enzymatic activity and enhance the abnormal aggregation of α-Syn in SH-SY5Y cells. Additionally, using an electrophoretic mobility shift assay, we confirmed that the binding efficiency of transcription factor E2F4 was affected by the rs12411216 SNP. In conclusion, our results showed that rs12411216 regulated GBA expression, supporting its potential role as a PD-MCI genetic biomarker and highlighting novel mechanisms underlying Parkinson's disease. [ABSTRACT FROM AUTHOR]

The different sensible heat fluxes across KEF (Kuroshio Extension front) is the main reason for the formation of baroclinicity in lower atmosphere in northwest Pacific. In this study, several sets of numerical experiments are performed to study the similarities and differences in sensible in lower atmosphere and their causes for a given intensity and location of KEF but for different background wind fields. The results show that under the influence of winter wind field, the effects of the perturbed air–sea temperature difference and the perturbed friction velocity make obvious positive contributions to the difference in heat flux across the KEF, and play a certain role in maintaining the baroclinicity in the lower atmosphere. In contrast, advection of the air–sea temperature anomaly by the perturbed friction velocity weakens the difference in heat flux across the KEF, which can significantly weaken the baroclinicity in the lower atmosphere. Under the influence of summer wind field, the perturbed surface wind reduces the difference in heat flux across KEF, which weakens the baroclinicity. The effects of the perturbed air–sea temperature difference and the advection of the perturbed air–sea temperature anomaly by the perturbed friction velocity make positive contributions to the difference in heat flux on both sides of the KEF, which effectively maintains baroclinicity in the lower atmosphere. However, the perturbed friction velocity weakens the difference in heat flux across the KEF, which significantly weakens the baroclinicity in the lower atmosphere. [ABSTRACT FROM AUTHOR]

The El Niño and the Southern Oscillation (ENSO) occurrence can be usually explained by two views of (i) a self-sustained oscillatory mode and (ii) a stable mode interacting with high-frequency forcing such as westerly wind bursts and Madden-Julian Oscillation events. The positive ocean–atmosphere feedback in the tropical Pacific hypothesized by Bjerknes leads the ENSO event to a mature phase. After ENSO event matures, negative feedbacks are needed to cease the ENSO anomaly growth. Four negative feedbacks have been proposed: (i) reflected Kelvin waves at the ocean western boundary, (ii) a discharge process due to Sverdrup transport, (iii) western-Pacific wind-forced Kelvin waves and (iv) anomalous zonal advections and wave reflection at the ocean eastern boundary. These four ENSO mechanisms are respectively called the delayed oscillator, the recharge–discharge oscillator, the western-Pacific oscillator and the advective–reflective oscillator. The unified oscillator is developed by including all ENSO mechanisms, i.e. all four ENSO oscillators are special cases of the unified oscillator. The tropical Pacific Ocean and atmosphere interaction can also induce coupled slow westward- and eastward-propagating modes. An advantage of the coupled slow modes is that they can be used to explain the propagating property of interannual anomalies, whereas the oscillatory modes produce a standing oscillation. The research community has recently paid attention to different types of ENSO events by focusing on the central-Pacific El Niño. All of the ENSO mechanisms may work for the central-Pacific El Niño events, with an addition that the central-Pacific El Niño may be related to forcing or processes in the extra-tropical Pacific. [ABSTRACT FROM AUTHOR]