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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]

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]

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]

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]