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The synthesis and electrochemical insertion of lithium into the Wadsley–Roth NaNb13O33 phase is studied. Lithium intercalation to form LixNaNb13O33 reaches a value of up to x~15, between 3.0 and 1.0 V vs. Li+/Li at a slow cycling rate, a capacity of 233 mAh g−1. Within this voltage window, two sharp peaks and one broad peak are observed in the differential capacity plots of lithium intercalation suggesting multiple two‐phase regions. High Li‐ion conductivity and rate capability was demonstrated. The lithium diffusion constant is about an order of magnitude greater than TiNb2O7. The average voltage is about 1.6 V and its high‐rate capability makes NaNb13O33 potentially useful as an anode in a fast‐charge Li‐ion battery application. [ABSTRACT FROM AUTHOR]

There has been increasing interest in using biochar for nutrient removal from water, and its application for anionic nutrient removal such as in phosphate (PO43−) necessitates surface modifications of raw biochar. This study produced avocado seed biochar (AB), impregnated Fe- or Mg-(hydr)oxide onto biochar (post-pyrolysis), and tested their performance for aqueous phosphate removal. The Fe- or Mg-loaded biochar was prepared in either high (1:8 of biochar to metal salt in terms of mass ratio) or low (1:2) loading rates via the co-precipitation method. A total of 5 biochar materials (unmodified AB, AB + High Fe, AB + Low Fe, AB + High Mg, and AB + Low Mg) were characterized according to their selected physicochemical properties, and their phosphate adsorption performance was tested through pH effect and adsorption isotherm experiments. Fe-loaded AB contained Fe3O4, while Mg-loaded AB contained Mg(OH)2. The metal (hydr)oxide inclusion was higher in Fe-loaded AB. Mg-loaded AB showed a unique free O–H functional group, while Fe-loaded AB showed an increase in its specific surface area more than 10-times compared to unmodified AB (1.8 m2 g−1). The effect of the initial pH on phosphate adsorption was not consistent between Fe-(anion adsorption envelope) vs. Mg-loaded AB. The phosphate adsorption capacity was higher with Fe-loaded AB in low concentration ranges (≤50 mg L−1), while Mg-loaded AB outperformed Fe-loaded AB in high concentration ranges (75–500 mg L−1). The phosphate adsorption isotherm by Fe-loaded AB fit well with the Langmuir model (R2 = 0.91–0.96), indicating the adsorptive surfaces were relatively homogeneous. Mg-loaded biochar, however, fit much better with Freundlich model (R2 = 0.94–0.96), indicating the presence of heterogenous adsorptive surfaces. No substantial benefit of high loading rates in metal impregnation was found for phosphate adsorption. The enhanced phosphate removal by Mg-loaded biochar in high concentration ranges highlights the important role of the chemical precipitation of phosphate associated with dissolved Mg2+. [ABSTRACT FROM AUTHOR]

Different weight ratios of polyaniline (PANI) to poly (acrylic acid) (PAA) were synthesized as interpenetrating polymer networks and blended with sulfonated poly (ether ether ketone) (SPEEK). In‐situ polymerization was performed by chemical oxidation of aniline in the presence of PAA. The composites showed actuation capability in the presence of fuel/air and moisture. Mechanical testing indicated that samples with higher concentration of PAA were stronger. For instance, PANI1PAA2SPEEK3 breaks at 8.4 MPa and has a failure strain of 2.5%, which is higher than PANI3PAA1SPEEK3 at 7 MPa and 2%. However, higher amount of PAA resulted in a lower electrochemical conductivity of 1.52 × 10−2 S/cm for the former and 1.8 × 10−2 S/cm for the latter. Intermolecular interaction at the optimum composition is necessary to induce forward and reverse bending of catalyst coated composite under exposure of fuel and air. In addition, the formation of compact structures and rough surfaces resulted in the maximal contractile strain of 1% for PANI3PAA1SPEEK3 based on moisture actuation. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the properties of well-rounded twists of a given ideal lattice of an imaginary quadratic field K. We show that every ideal lattice I of K has at least one well-rounded twist lattice. Moreover, we provide an explicit algorithm to compute all well-rounded twists of I. [ABSTRACT FROM AUTHOR]

Elastomeric stamp deformation was used to fabricate a series of new metal thin film patterns not present on the original stamp. The rounded patterns are of nanoscale thickness, long-range order, and are created from elastomeric stamps with only straight-edged features and the feature size, separation, relief height, stamp elasticity and external force control the morphology and appearance of shape.

The crystal structure, thermal properties and magnetic properties of a three-dimensional (3D) metal-organic open framework, with infinite one-dimensional (1D) Cu(II) oxide chains embedded in the structure are described. The studies indicate that the framework is a 1D antiferromagnetic system with a Neel temperature of 51 K and a paramagnetic impurity dominates the susceptibility below 14 K, implying the synthesized compound to be highly pure.

The viability of converting wood chips and plastic to power via compact integrated catalytic fast/slow pyrolysis, combustor, and Stirling engine technologies was determined using modeling analysis. Aspen simulations followed by sizing analysis were performed to determine the size, weight, and net energy efficiency of upgrading wood chips and plastic to power using a compact energy system with a feedstock processing capacity of 1 kg h−1. The equipment and tooling to fabricate individual components of a compact energy system were identified. The total costs of fabricating all the individual components of compact energy systems were assessed. A discounted cash flow analysis with an internal rate of return of 20% was used to assess the minimum selling price of compact energy systems. The specific energy (Wh kg−1) of the compact catalytic fast pyrolysis system, compact slow pyrolysis system, and compact plastic conversion system were assessed at 20, 29, and 63, respectively. The assessed capital and annual costs of manufacturing 10 000 compact energy systems per year were $51 million and about $11 to $13 million, respectively. The calculated minimum selling price of a catalytic fast pyrolysis system, a compact slow pyrolysis system, and a compact plastic conversion system were $3055, $3021, and $2980, respectively. The sensitivity analysis results showed that the internal rate of return, capital investment, materials cost, annual operating costs, and capital cost have significant impacts on the minimum selling price of compact energy systems. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Herein we report a method for the synthesis of 2‐aryl thiochromenones via a sulfuration of 2'‐chlorochalcones. The chalcones could be prepared in advance or in situ obtained from 2'‐chloroacetophenones and aromatic aldehydes. The conditions were tolerant of functionalities including chloro, fluoro, methylthio, phenoxy, and trifluoromethyl groups. 2‐Heteroaryl thiochromenones could also be obtained in moderate yields. Our method appears to be a simple, general tactic to afford 2‐aryl thiochromenones from commercial starting materials. [ABSTRACT FROM AUTHOR]