Pre-Oxidation Strategy Transforming Waste Foam to Hard Carbon Anodes for Boosting Sodium Storage Performance.

Large reserves, high capacity, and low cost are the core competitiveness of disordered carbon materials as excellent anode materials for sodium-ion batteries (SIBs). And the existence and improper treatment of a large number of organic solid wastes will aggravate the burden on the environment, therefore, it is significant to transform wastes into carbon-based materials for sustainable energy utilization. Herein, a kind of hard carbon materials are reported with waste biomass-foam as the precursor, which can improve the sodium storage performance through pre-oxidation strategy. The introduction of oxygen-containing groups can promote structural cross-linking, and inhibit the melting and rearrangement of carbon structure during high-temperature carbonization that produces a disordered structure with a suitable degree of graphitization. Moreover, the micropore structure are also regulated during the high-temperature carbonization process, which is conducive to the storage of sodium ions in the low-voltage plateau region. The optimized sample as an electrode material exhibits excellent reversible specific capacity (308.0 mAh g-1) and initial Coulombic efficiency (ICE, 90.1%). In addition, a full cell with the waste foam-derived hard carbon anode and a Na3V2(PO4)3 cathode is constructed with high ICE and energy density. This work provides an effective strategy to conversion the waste to high-value hard carbon anode for sodium-ion batteries.

catena-Poly[disilver(I)(Ag-Ag)-bis-(µ(3)-quinoline-3-carboxyl-ato)-1:2:1'κ(3)O:O':N;2:1'':2''κ(3)N:O:O'].

In the title compound, [Ag(2)(C(10)H(6)NO(2))(2)](n), the Ag(I) atom is coordinated by one N atom and two O atoms from three quinoline-3-carboxyl-ate ligands in a T-shaped fashion, with an additional Ag⋯Ag distance of 2.9468 (6) Å. The ligands connect the Ag(I) atoms into a double-chain structure along [010]. Weak Ag⋯O inter-actions [Ag⋯O = 2.802 (3) and 2.877 (4) Å] link the double-chains into a layer network parallel to (101). π-π inter-actions are also observed in the layer network [centroid-centroid distances = 3.780 (3) and 3.777 (3) Å].

Poly[(µ(2)-quinoline-3-carboxyl-ato-κN:O)(µ(2)-quinoline-3-carboxyl-ato-κN:O,O')cadmium].

In the title compound, [Cd(C(10)H(6)NO(2))(2)](n), the Cd(II) atom is coordinated by three O atoms and two N atoms from four quinoline-3-carboxyl-ate (L(-)) ligands, leading to a distorted trigonal-bipyramidal geometry. The L(-) ligands link the Cd(II) atoms into a plane parallel to (100), with one ligand being tridentate, coordinating via the N atom and chelating a second Cd atom, and the other being bidentate, bridging two Cd atoms via the N and one O atom.. This two-dimensional network extends into a double-layer network by π-π inter-actions, with centroid-centroid distances of 3.680 (2) and 3.752 (2) Å. Another type of π-π inter-action between pyridine rings [centroid-centroid distance = 3.527 (2) Å] leads to a three-dimensional supra-molecular architecture.

Hi-Res scan mode in clinical MDCT systems: Experimental assessment of spatial resolution performance.

PURPOSE: The introduction of a High-Resolution (Hi-Res) scan mode and another associated option that combines Hi-Res mode with the so-called High Definition (HD) reconstruction kernels (referred to as a Hi-Res/HD mode in this paper) in some multi-detector CT (MDCT) systems offers new opportunities to increase spatial resolution for some clinical applications that demand high spatial resolution. The purpose of this work was to quantify the in-plane spatial resolution along both the radial direction and tangential direction for the Hi-Res and Hi-Res/HD scan modes at different off-center positions. METHODS: A technique was introduced and validated to address the signal saturation problem encountered in the attempt to quantify spatial resolution for the Hi-Res and Hi-Res/HD scan modes. Using the proposed method, the modulation transfer functions (MTFs) of a 64-slice MDCT system (Discovery CT750 HD, GE Healthcare) equipped with both Hi-Res and Hi-Res/HD modes were measured using a metal bead at nine different off-centered positions (0-16 cm with a step size of 2 cm); at each position, both conventional scans and Hi-Res scans were performed. For each type of scan and position, 80 repeated acquisitions were performed to reduce noise induced uncertainties in the MTF measurements. A total of 15 reconstruction kernels, including eight conventional kernels and seven HD kernels, were used to reconstruct CT images of the bead. An ex vivo animal study consisting of a bone fracture model was performed to corroborate the MTF results, as the detection of this high-contrast and high frequency task is predominantly determined by spatial resolution. Images of this animal model generated by different scan modes and reconstruction kernels were qualitatively compared with the MTF results. RESULTS: At the centered position, the use of Hi-Res mode resulted in a slight improvement in the MTF; each HD kernel generated higher spatial resolution than its counterpart conventional kernel. However, the MTF along the tangential direction of the scan field of view (SFOV) was significantly degraded at off-centered positions, yet the combined Hi-Res/HD mode reduced this azimuthal MTF degradation. Images of the animal bone fracture model confirmed the improved spatial resolution at the off-centered positions through the use of the Hi-Res mode and HD kernels. CONCLUSIONS: The Hi-Res/HD scan improve spatial resolution of MDCT systems at both centered and off-centered positions.